OSHA enacted the OSHA safety program guideline for infection control in dental care settings in 2003. Because dental patients and dental health care personnel are at risk for viral and bacterial infections, there must be guidelines to control these types of risks.
The Office of Occupational Safety & Health Administration, better known as OSHA is the main federal agency charged with the enforcement of safety and health legislation. Enacted in 1971, OSHA's primary responsibility is to ensure that employers create safe working environments for its employees. OSHA laws apply to all private employers, regardless of the size of the company. Companies found to be non-compliant with these regulations can face OSHA occupational health and safety fines of up to $70,000, depending on the severity of the violation.
According to the OSHA safety program, a successful infection-control program depends on developing standard operating procedures, evaluating practices, routinely documenting adverse outcomes and work-related illnesses in dental health care personnel, and monitoring health-care associated infections in patients. The OSHA safety program guideline is based upon recommendations developed in collaboration with infection control authorities from Centers for Disease and Control (CDC), other public agencies, academia, and private and professional organizations and was designed to provide guidance to dental health care personnel, as well as to dental practices in developing and implementing infection-control programs.
While the number of published studies concerning dental infection control has increased in recent years, questions regarding infection control practices and their effectiveness remain unanswered. Multiple concerns were identified by the group working on the report and by others during the public comment period. Based upon these concerns, recommendations were submitted along with the OSHA safety program guidelines.
The OSHA safety program guideline is summarized below. It focuses primarily on issues which directly affect the dental patient. Each summary is followed by an OSHA safety program guideline recommendation, if applicable. While each recommendation was categorized on the basis of existing scientific data, theoretical rationale, and applicability, and rank by a system used by the CDC and the Healthcare Infection Control Practices Advisory Committee (HICPAC), the ranking information was omitted for brevity purposes.
Dental patients and dental health care personnel can be exposed to pathogenic microorganisms including cytomegalovirus (CMV), Hepatitis B, Hepatitis C, herpes simplex virus types 1 and 2, HIV, Mycobacterium tuberculosis, staphylococci, streptococci, and other viruses and bacteria that colonize or infect the oral cavity and respiratory tract. These organisms can be transmitted in dental settings through the following ways:
Infection through any of these routes requires that certain conditions exist. The existence of these conditions provides the chain of infection. An effective infection control strategy prevents disease transmission by interrupting one or more links in the chain.
Previous CDC recommendations regarding infection control for dentistry focused primarily on the risk of transmission of blood borne pathogens among dental health care providers and patients and the use of universal precautions to reduce that risk. In 1996, due to awareness of other aspects of disease transmission besides blood borne pathogens, the CDC expanded the concept and changed the term to standard precautions. Standard precautions integrated and expanded the elements of universal precautions into a standard of care designed to protect health care providers and patients from pathogens that could spread by blood or any other body fluid, excretion, or secretion, skin cuts and abrasions, and mucous membranes.
In addition to standard precautions, other measures may be necessary to prevent the potential spreading of certain diseases that are transmitted through airborne, droplet, sneezing, coughing, and contact with the skin. When acutely ill with these diseases, patients do not usually seek routine dental outpatient care. Nonetheless, a general understanding of precautions for diseases transmitted by all routes is critical because some dental health care providers work in hospital settings and patients infected with these types of diseases may seek urgent treatment at their facility, posing a risk to the dental health care provider. Necessary transmission based precautions may include patient isolation, adequate room ventilation, protection masks for the dental care provider or postponement of non emergency dental procedures.
Dental health care providers should be familiar with the hierarchy of controls that categorizes and prioritizes prevention strategies. For blood borne pathogens, controls that eliminate or isolate the hazard, such as puncture resistant sharps containers or needle retraction device, are the primary strategies for protecting dental health care providers and patients. When these types of controls are not available or appropriate, work practice controls which result in safer behaviors, such as one-hand needle recapping or not using fingers for cheek retraction while using sharp instruments or suturing, and using personal protective equipment (PPE), such as protective eyewear, gloves, and masks, can prevent exposure. In addition, administrative policies, procedures, and enforcement measures targeted at reducing the risk of exposure to infectious persons, are a priority for certain pathogens, particularly those spread by airborne or droplet routes.
All dental care facilities should have a written infection control program to prevent or reduce the risk of disease transmission. The program should include establishment and implementation of policies, procedures, and practices, in conjunction with the use of technologies and products, to prevent work-related injuries and illnesses among dental health care providers as well as health care associated infections among patients. The effectiveness of the infection control program should be evaluated daily to help ensure that policies, procedures, and practices are useful, efficient, and successful. Such programs should include the following, with the object being to identify work-related infection risks, institute preventive measures, and ensure prompt exposure management and medical follow-up:
In addition, written policies and procedures should be consistent with federal, state, and local requirements addressing education and training, post exposure management and exposure reporting documentation.
Personnel subject to occupational exposure should receive infection-control training on initial assignment, when new tasks or procedures affect their occupational exposure, and at a minimum, annually.Education and Training - OSHA Safety Program Recommendations
Same as above, but also to provide education and training regarding occupational exposure to potentially infectious agents and infection-control procedures/protocols in appropriate content and vocabulary to the educational level, literacy, and language of dental health care provider.
Dental health care providers are at risk for exposure and possible infection with infectious organisms. Immunizations substantially reduce both the number of dental health care providers susceptible to these diseases and the potential for disease transmission to other dental health care providers and patients. Thus, immunizations are an essential part of prevention and infection-control programs for dental health care providers, and a comprehensive immunization policy should be implemented for all dental health-care facilities. Immunization of dental health care providers before they are placed at risk for exposure remains the most efficient and effective use of vaccines in health-care settings.Immunization Programs - OSHA Safety Program Recommendations
Develop a written comprehensive policy regarding immunizing dental health care providers, including a list of all required and recommended immunizations and provide appropriate referrals, whether through a prearranged qualified health-care professional or to the dental health care provider's own health-care professional. Dental health care providers should receive all appropriate immunizations based on the latest recommendations, as well as, their own medical history and risk for occupational exposure.
In addition to immunization, the primary strategies for reducing occupational infections include the avoidance of exposure to blood and other potentially infectious material. While such exposures do occur, a combination of standard procedures, engineering, and administrative controls is the best means to minimize these exposures. There should be available to all dental health care providers, written policies and procedures to facilitate prompt reporting, evaluation, counseling, treatment and medical follow up for all occupational exposures.Exposure Prevention and Post Exposure Management - OSHA Safety Program Recommendations
A comprehensive post exposure management and medical follow-up program must be developed. This program should include policies and procedures for prompt reporting, evaluation, counseling, treatment, and medical follow up of all occupational exposures, which may include conducting a baseline TST, preferably by using a two-step test, for all dental health care providers who may have contacted with persons with suspected or confirmed infectious TB.
Dental health care providers are responsible for monitoring their own health status. Those who have acute or chronic medical conditions that render them susceptible to infection should find out if their condition affects their ability to safely perform their duties. Under certain circumstances, health care facility managers may exclude dental health care providers from work or patient contact to prevent further transmission of infection. Work restrictions are usually based on the mode of transmission and the stage of the disease.Medical Conditions, Work-Related Illness and Restrictions - OSHA Safety Program Recommendations
Dental facilities should have available to all dental health care personnel, comprehensive written policies regarding work restriction and exclusions. These policies should be developed in a manner that encourages dental health care providers to seek preventive and curative care and to report any illnesses, medical conditions, or treatments which can expose them to infection or exposures. Dental health care providers should not be penalized with loss of wages, benefits, or job status.
With regards to occupational contact dermatitis, dental facilities should also develop policies and procedures for evaluating, diagnosing and managing dental health care personnel. A definitive diagnosis made by a qualified health care professional for any dental health care provider with suspected latex allergy should be made in order to determine its specific etiology and the appropriate treatment needed, in addition to any work restrictions or special accommodations which may be necessary.
Although transmission of blood borne pathogens, such as Hepatitis B, Hepatitis C and HIV, in dental health care settings can have serious consequences, such transmission is rare. Exposure to infected blood can result in transmission from patient to dental health care provider, from dental health care provider to patient, and from one patient to another. The opportunity for transmission is greatest from patient to dental health care provider, who frequently encounter patient blood and blood contaminated saliva when performing dental procedures.
Since 1992, no HIV transmission from a dental health care provider to a patient has been reported, and the last Hepatitis B transmission from a dental health care provider to a patient was reported in 1987. There has never been a report of Hepatitis C being transferred from a dental health care provider to a patient.
The majority of dental health care providers infected with a blood borne virus pose no risk to a patient because they do not perform the activities necessary for transmitting the virus. In order for the dental health care provider to pose a risk to a patient, three (3) conditions must be met:
Condition #1: The dentist must have an infectious virus circulating in their bloodstream.
Condition #2: The dentist must be injured or have a condition, such as weeping dermatitis which allows for direct exposure to their blood or other infectious body fluids.
Condition #3: The dentist must allow their blood or infectious body fluid to gain direct access to a patient's wound, traumatized tissue, mucous membranes, or similar portal of entry.
Although an infected dental health care provider may have condition #1 (be viremic), if the 2nd and 3rd conditions are not present, no transmission of a virus can occur.
The risk of occupational exposure to blood borne viruses is largely determined by their prevalence in the patient population and the nature and frequency of contact with blood and body fluids through the skin or other routes of exposure. The risk of infection after exposure to a blood borne virus is influenced by its size, the route of exposure, and the susceptibility level of the exposed health care provider.
Because of the different levels of risk associated with Hepatitis B, Hepatitis C, HIV and dental health care providers, a lot of focus is placed on these blood born pathogens.
The Hepatitis B Virus is a well known occupational risk for health care providers. Hepatitis B is transmitted by the skin or mucosal exposure to blood or body fluids of a person with either acute or chronic Hepatitis B infection. Persons infected with Hepatitis B can transmit the virus for as long as they are HBsAg-positive. According to studies conducted, the risk of Hepatitis B transmission is highly related to the HBeAg status of the source person
Blood contains the greatest proportion of Hepatitis B infectious particle titers of all body fluids and is the most critical vehicle of transmission in the health care setting. Although skin injuries are among the most efficient modes of Hepatitis B transmission, investigations and studies show that these exposures probably account for only a small fraction of Hepatitis B infections among health care professionals. Hepatitis B has the ability to survive in dried blood at room temperature on environmental surfaces for less than 1 week and the potential for itstransmission through contact with environmental surfaces has been demonstrated in investigations of Hepatitis B outbreaks among patients and health care professionals in hemodialysis units.
Since the early 1980s, occupational infections among health care professionals have declined because of vaccine use and adherence to universal precautions. Among U.S. dentists, over 90% have been vaccinated, and evidence of past Hepatitis B infection decreased from prevaccine levels of 14% in 1972 to approximately 9% in 1992. During 1993--2001, the levels of infection remained relatively unchanged. Infection rates are expected to decline further, as vaccination rates remain high among young dentists and as older dentists with lower vaccination rates and higher rates of infection, retire from the field of dentistry.
While the potential for transmitting blood borne infections from dental health care professionals to patients is considered limited, the precise risks have not been quantified by epidemiologic studies. Reports published during 1970--1987 describe nine clusters in which patients were thought to be infected with Hepatitis B through treatment by an infected dental health care provider. However, transmission of Hepatitis B from dentist to patient has not been reported since 1987, possibly reflecting such factors as adoption of universal precautions and/or the 1991 OSHA Safety Program blood borne pathogen standards, which include routine glove use and Hepatitis B vaccination. Or, it may be the result of incomplete ascertainment and reporting by dental care facilities.
Only one case in the dental care setting of a patient transmitting Hepatitis B to another patient has been documented (CDC, unpublished data, 2003). In this case, appropriate office infection control procedures were being followed, and the exact mechanism of transmission was unable to be determined.
Because of the high risk of Hepatitis B infection among health care professionals, dental health care professionals who perform tasks which may involve contact with blood, blood contaminated body substances, other body fluids, or sharps, should be vaccinated. Vaccination can protect both the dental health care provider and the patient from Hepatitis B infection. Vaccination should occur and be completed when dentists, or other dental health care professionals, are in training and before they have contact with blood.
Vaccine induced antibodies decline gradually over time, and 60% of persons who initially respond to vaccination will lose detectable antibodies in a period of over 12 years. Nonetheless, immunity continues to prevent clinical disease or detectable viral infection.Hepatitis B Vaccination - OSHA Safety Program Recommendations
Hepatitis B vaccination series should be offered to all dental health care professionals, while following the U.S. Public Health Service/CDC recommendations for hepatitis B vaccination, serologic testing, follow-up, and booster dosing. Employees should also be provided with education regarding the risks of Hepatitis B transmission and the availability of the vaccine. Employees who decline the vaccination should sign a declination form which is kept on file with the employer.
Counseling should be made available to dental health care providers who are HBsAg-negative. Counseling should involve discussions regarding their susceptibility to Hepatitis B infection and the precautions they need to take when administering dental care.
An estimated 4% of persons with acute Hepatitis B infection are also infected with Hepatitis D virus. Discovered in 1977, Hepatitis D is a defective blood borne virus requiring the presence of Hepatitis B to replicate. Patients co-infected with Hepatitis B and Hepatitis D have substantially higher mortality rates than those infected with Hepatitis B alone. Because Hepatitis D infection is dependent on Hepatitis B for replication, immunization to prevent Hepatitis B infection, through either pre- or post exposure prophylaxis, can also prevent Hepatitis D infection.
Hepatitis C virus does not appear to be transmitted efficiently through occupational exposures to blood. Follow up studies conducted of health care professionals who were exposed to Hepatitis C infected blood through skin or other sharps injuries revealed a low incidence of seroconversion. One study determined Hepatitis C transmission had occurred from hollow-bore needles, but not other sharps. Although these studies have not documented seroconversion associated with mucous membrane or broken skin exposure, at least two cases of Hepatitis C transmission from a blood splash to the conjunctiva and one case of simultaneous transmission of Hepatitis C and HIV after broken skin exposure have been reported.
There is not enough sufficient data available to estimate the occupational risk of Hepatitis C infection among health care professionals, but the majority of studies indicate that the prevalence of Hepatitis C infection among dentists, surgeons, and hospital-based health care professional is similar to that among the general population, approximately 1%--2%. In a study that evaluated risk factors for infection, a history of unintentional needle sticks was the only occupational risk factor independently associated with the Hepatitis C infection.
There have been no studies reported of the transmission from Hepatitis C infected dental health care professionals to patients, and the risk appears limited. Multiple reports have been published describing transmission from Hepatitis C infected surgeons, which apparently occurred during the performance of invasive procedure. The overall risk assessment for the Hepatitis C Virus being transferred from a surgeon to a patient averaged 0.17%.
The risk of HIV transmission in dental settings is extremely low in the U.S. As of December 2001, after occupational exposure to an HIV infected source, there were a total of 57 cases of HIV seroconversion documented among health care professionals, but none among dental health care providers. While there has been a case of transmission of HIV from a single dentist with AIDS to six patients, the mode of transmission could not be determined. As of September, 1993, the CDC had information regarding the test results of over 22,000 patients of 63 HIV-infected health care professionals, including 33 dentists or dental students. No additional cases of transmission have been documented.
Prospective studies worldwide indicate the average risk of HIV infection after a single skin exposure to HIV-infected blood is 0.3%. After an exposure of mucous membranes in the eye, nose, or mouth, the risk is approximately 0.1%. The precise risk of transmission after skin exposure remains unknown, but is believed to be even smaller than that for mucous membrane exposure.
Certain factors affect the risk of HIV transmission after an occupational exposure. Laboratory studies have determined that if needles which pass through latex gloves are solid rather than hollow-bore, or are of small gauge, similar to the anesthetic needles commonly used in dentistry, less blood is transferred. In a retrospective case-control study of health care professionals, an increased risk for HIV infection was associated with exposure to a relatively large volume of blood, as indicated by a deep injury with a device that was visibly contaminated with the patient's blood, or a procedure that involved a needle placed in a vein or artery. The risk was also increased if the exposure was to blood from patients with terminal illnesses, possibly reflecting the higher titer of HIV in late stage AIDS.
Avoiding occupational exposures to blood is the primary way to prevent transmission of Hepatitis B, Hepatitis C, and HIV, to health care professionals in health care settings. Exposures occur through skin injuries, as well as through contact between potentially infectious blood, tissues, or other body fluids and mucous membranes of the eye, nose, mouth, or exposed skin that is chapped, abraded, or shows signs of dermatitis.
Skin injuries that do occur among dental health care providers usually happen outside the patient's mouth. It is usually caused by burs, syringe needles, laboratory knives or other sharp instruments. When injuries occur outside the patient's mouth, there is less risk for the contact of exposure to recontact with tissues of the patient and it usually involves a limited mounts of blood.
Observational studies and surveys indicate that skin injuries among general dentists and oral surgeons occurs less frequently than among general and orthopedic surgeons and have decreased in frequency since the mid-1980s. This decline has been attributed to safer work practices, safer instrumentation or design, and continued dental health care provider education. Injuries among oral surgeons may be more frequent during fracture reductions using wires.
The majority of exposures in dentistry are preventable. The methods used to reduce the risk of blood contact include the use of standard precautions, as well as devices with features designed to prevent sharp injuries. Standard precautions include use of personal protection equipment such as gloves, masks, protective eyewear or face shield, and gowns, intended to prevent skin and mucous membrane exposures. Other protective equipment such as finger guards while suturing, may also reduce injuries during the application of dental procedures. Engineering design controls are the primary method to reduce exposures to blood and other potentially infectious materials from sharp instruments and needles. These controls are frequently technology-based and often incorporate safer designs of instruments and devices to reduce skin injuries. These approaches might have contributed to the decrease in skin injuries among dentists during recent years. However, needle sticks and other blood contacts continue to occur, which is a concern because skin injuries pose the greatest risk of transmission.
Needles sticks are a substantial source of skin injury in dental practice, and engineering and work-practice controls for needle handling are of particular importance. In 2001, revisions to OSHA's blood borne pathogens standard as mandated by the Needlestick Safety and Prevention Act of 2000 became effective. These revisions clarified the need for employers to consider safer needle devices as they become available and to involve employees directly responsible for patient care in identifying and choosing such devices. Safer versions of sharp devices used in hospital settings have become available, and their impact on reducing injuries has been documented. Aspirating anesthetic syringes that incorporate safety features have been developed for dental procedures, but the low injury rates in dentistry limit assessment of their effect on reducing injuries among dental health care providers.
Post exposure management is an integral component of a complete program to prevent infection after an occupational exposure to blood. During dental procedures, saliva is predictably contaminated with blood. Even when blood is not visible, it can still be present in limited quantities and therefore is considered a potentially infectious material by OSHA. A qualified health care professional should evaluate any occupational exposure incident to blood or other potentially infectious materials, including saliva, regardless of whether blood is visible, in dental settings.
Dental practices and laboratories should establish written, comprehensive programs that include Hepatitis B vaccination and post exposure management protocols. Dental health care providers, including students, who might reasonably be considered at risk for occupational exposure to blood or other potentially infectious materials, should be taught strategies to prevent contact with blood or other potentially infectious materials and the principles of post exposure management, as part of their job orientation and training. Educational programs for dental health care providers and students should emphasize reporting all exposures to blood or other potentially infectious materials as soon as possible, because certain interventions have to be initiated promptly to be effective. Policies should be consistent with the practices and procedures for worker protection required by the OSHA Safety Program and with current Public Health Service recommendations for managing occupational exposures to blood.
Dental health care providers should incorporate standard precautions for all patient encounters. They should consider sharp items that are contaminated with patient blood and saliva as potentially infective and establish engineering controls and work practices to prevent injuries. Dental facilities should implement a written, comprehensive program designed to minimize and manage dental health care provider exposures to blood and body fluids.Engineering and Work-Practice Controls
Dental facilities should identify, evaluate, and select devices with engineered safety features at least annually and as they become available on the market.
All disposable syringes and needles, scalpel blades, and other sharp items should be placed in appropriate puncture resistant containers located as close to the area in which the items are being used during dental treatment.
Dentist should use either a one-handed scoop technique or a mechanical device designed for holding the needle cap when recapping needles. Needles should not be recapped using both hands, or by using any technique that involves directing the point of a needle toward any part of the body. Needles should be properly disposed of using standard protocols.
CDC recommendations should be followed for skin, mucous membrane, or non intact skin exposure to blood or other potentially infectious materials.
Regularly incorporating a hand hygiene regiment substantially reduces potential pathogens on the hands. Hand hygiene is considered the most single critical measure for reducing the risk of transmitting organisms to patients and health care providers. Hospital based studies show that noncompliance to hand hygiene practices is associated with health care associated infections and the spread of multi resistant organisms, and a major cause of outbreaks. Health care associated infections are decreasing, as a result of adherence of health care professionals to recommended hand hygiene measures.
Hand hygiene protocols should be followed when hands are visibly soiled or after touching inanimate objects likely to be contaminated by blood, saliva, or respiratory secretions. The protocol should also be followed before and after treating each patient and before applying and immediately after removing gloves. When hands are visibly dirty, contaminated with blood or other potentially infectious material, clean them with either a non-antimicrobial or antimicrobial soap and water. If hands are not visibly soiled, an alcohol-based hand rub should be used.
Prior to performing any oral surgery procedures, hands should be washed using either an antimicrobial soap and water, or soap and water followed by a thorough drying of the hands and then applying an alcohol-based surgical hand-scrub product.
Store liquid hand care products in either disposable closed containers or closed containers that can be washed and dried before refilling. Do not add soap or lotion to a partially empty dispenser.
Use hand lotions to prevent skin dryness associated with hand washing. Also, consider the compatibility of lotion and antiseptic products and the effect of petroleum or other oil emollients on the integrity of gloves.
The use of artificial fingernails is not recommended, especially when having direct contact with patients at high risk areas. Keep fingernails short with smooth, filed edges to allow for thorough cleaning and in order to prevent glove tears. Dental health care providers should also avoid wearing hand or nail jewelry if applying gloves is difficult or if the jewelry compromises the fit and integrity of the glove.
Personal Protective Equipment is designed to protect the skin and the mucous membranes of the eyes, nose, and mouth of dental health care providers from exposure to blood or other potentially infectious materials. Use of rotary dental and surgical instruments and air-water syringes creates a visible spray that contains large particle droplets of water, saliva, blood, microorganisms, and other debris. This spatter travels only a short distance and settles out quickly, landing on the floor, nearby operatory surfaces, the dental health care provider and/or the patient. The spray may also contain certain aerosols which can remain airborne for extended periods and also be inhaled. This is not the same aerosol spray that makes up the bulk of the spray from dental hand pieces and ultrasonic scalers. Appropriate work practices, including the use of dental dams and high-velocity air evacuation, should minimize dissemination of droplets, spatter, and aerosols.
Primary personal protective equipment used in oral health care settings includes gloves, surgical masks, protective eyewear, face shields, and protective clothing, such as gowns and lab coats. Dental health care providers should remove all PPE before leaving patient care areas. Reusable personal protective equipment, such as protective eyewear and face shields, should be cleaned with soap and water, and when visibly soiled, disinfected accordingly. Especially, before treating the next patient. The OSHA Safety Program has mandated the specific wearing of gloves, surgical masks, protective eyewear, and protective clothing in specified circumstances, as a way to reduce the risk of exposures to blood borne pathogens. General work clothes, such as uniforms, scrubs, pants, and shirts are neither intended to protect against a hazard nor considered personal protective equipment, and therefore should not be worn as such.
A surgical mask that covers both the nose and mouth and protective eyewear with solid side shields or a face shield should be worn by dental health care providers during dental procedures which may involve splashes or sprays of blood or body fluids. Dental patients should also be offered protective eyewear to shield the eyes from spatter or debris generated during dental procedures.
A surgical mask protects against microorganisms generated by the wearer, with greater than 95% bacterial filtration efficiency, and also protects dental health care providers from splatter that may contain blood borne pathogens or other infectious microorganisms. The outer surface of the mask can also become contaminated with infectious droplets from spray of oral fluids or from touching the mask with contaminated fingers, while a wet mask from exhaled moist air can increase the resistance to airflow through the mask. Therefore, a mask should be changed either between patients or even during patient treatment, when possible.
Most surgical masks do not adequately protect the user from exposure to TB, and do not satisfy OSHA requirements for respiratory protection. However, certain surgical masks do meet the requirements and are certified as respirators. The level of protection a respirator provides is determined by the efficiency of the filter material for incoming air and how well the face piece fits or seals to the face.
Dentists should use a surgical mask and eye protection with solid side shields or a face shield to protect mucous membranes of the eyes, nose, and mouth during dental procedures. These masks should be changed between patients, as well as during treatment, if necessary. Any reusable facial equipment should be cleaned with soap and water, or if visibly soiled, cleaned and disinfected between patients. Patients should be offered the use of protective glasses during dental procedures.Protective Clothing
The use of protective clothing and equipment prevents contamination of street clothing and also protects the skin of dental health care providers from exposures to blood and body substances. The OSHA Safety Program blood borne pathogens standard requires that sleeves are long enough to protect the forearms when being used as personal protective equipment. Dental health care providers should change protective clothing when it becomes visibly soiled and as soon as feasible if penetrated by blood or other potentially infectious fluids. All protective clothing should be removed before leaving the work area.
Dentists should ear protective clothing that covers personal clothing and skin likely to be soiled with blood, saliva, or other potential infectious material. These items should be changed if they become visibly soiled and should be removed prior to leaving the patient care area.
Dental health care providers wear gloves to prevent contamination of their hands when touching mucous membranes, blood, saliva, or other potentially infectious materials, and to reduce the likelihood that microorganisms present on the hands of dental health care providers will be transmitted to patients during surgical or other patient care procedures. Medical gloves, both patient examination and surgeon's gloves, are manufactured as single use disposable items that should be used for only one patient, then discarded. Gloves should be changed between patients and when torn or punctured.
The use of gloves does not eliminate the need for hand washing. Hand hygiene should be performed immediately before applying gloves. Because bacteria can multiply rapidly in the moist environments underneath gloves, hands should be dried thoroughly before putting on, and immediately after removing gloves. Gloves can also contain small, unapparent defects or be torn during use, causing the hands to become contaminated during their removal. Studies have demonstrated that both health care providers and dental health care providers are frequently unaware of minute tears in gloves that occur during use. These studies determined that gloves developed defects in 30 minutes to 3 hours, depending on type of glove and procedure.
Studies have demonstrated that both health care providers and dental health care providers are frequently unaware of minute tears in gloves that occur during use. These studies determined that gloves developed defects in 30 minutes to 3 hours, depending on type of glove and procedure. Investigators did not determine an optimal time for changing gloves during procedures.
The Food and Drug Administration regulates the medical glove industry, which includes gloves marketed as sterile surgeon's and sterile or non-sterile patient examination gloves. General-purpose utility gloves are also used in dental health care settings, but they are not regulated by FDA, as they are not promoted for medical use. More rigorous standards are applied to surgeon's gloves than to patient examination gloves. The FDA has identified acceptable quality levels for glove manufacturers, but even intact gloves eventually fail with exposure to mechanical and chemical hazards and over time. These variables can be controlled, ultimately optimizing glove performance, if the dental health care provider maintains short fingernails, minimizes or eliminates hand jewelry, and uses engineering and work-practice controls to avoid injuries with sharps.
Dentists should wear medical gloves when a potential exists for contacting blood, saliva, other potentially infectious materials, or mucous membranes. They should also wear a new pair of medical gloves for each patient, remove them promptly after use, and wash their hands immediately to avoid transfer of microorganisms to other patients or environments. If gloves should become torn, cut, or punctured, they should be removed as soon as possible, with the hands being washed and dried before applying another pair.
Dentists should wear sterile surgeon's gloves when performing oral surgical procedures. While the OSHA Safety Program offers no recommendations regarding the effectiveness of wearing two pairs of gloves to prevent disease transmission during oral surgical procedures, the majority of studies among health care providers and dental health care providers have demonstrated a lower frequency of inner glove perforation and visible blood on the surgeon's hands when double gloves are worn. However, the effectiveness of wearing two pairs of gloves in preventing disease transmission has not been demonstrated.
Occupationally related contact dermatitis can develop from frequent and repeated use of hand hygiene products, exposure to chemicals, and glove use. Contact dermatitis is classified as either irritant or allergic. Irritant contact dermatitis is common, non allergic, and develops as dry, itchy, irritated areas on the skin around the area of contact. By comparison, allergic contact dermatitis, Type IV Hypersensitivity, can result from exposure to accelerators and other chemicals used in the manufacture of rubber gloves, as well as from other chemicals found in the dental practice setting. Allergic contact dermatitis often manifests as a rash beginning hours after contact and, similar to irritant dermatitis, is usually confined to the area of contact.
Latex allergy, Type I Hypersensitivity to Latex Proteins, can be a more serious systemic allergic reaction. It usually begins within minutes of exposure, but can also occur hours later and produce varied symptoms. The more common reactions may include a runny nose, sneezing, itchy eyes, scratchy throat, hives, and itchy burning skin sensations. The more severe symptoms include asthma marked by difficult breathing, coughing spells, wheezing, cardiovascular and gastrointestinal ailments, and in rare cases, anaphylaxis and death. The ADA began investigating the prevalence of Type I Latex Hypersensitivity among dental health care providers at their annual meeting in 1994. The study found a decline for hypersensitivity, attributing it to the increased use of latex gloves containing a lower content of allergen.
Natural rubber latex proteins responsible for latex allergy are attached to glove powder. When powdered latex gloves are worn, more latex protein reaches the skin. The process of putting on or removing these types of gloves results in latex protein/powder particles become aerosolized and being inhaled and contacting the mucous membranes. As a result, allergic patients and dental health care providers can experience cutaneous, respiratory, and conjunctival symptoms related to latex protein exposure. Dental health care providers and dental patients with latex allergies should not have direct contact with materials containing latex and should be in an environment free from all latex containing products. Any dental devices containing latex that cannot be removed from the treatment environment should be adequately covered or isolated.
Dental patients may also be allergic to chemicals used in the manufacture of natural rubber latex and synthetic rubber gloves, as well as metals, plastics, or other materials used in dental care. Certain common predisposing conditions for latex allergy include previous history of allergies, a history of spina bifida, urogenital anomalies, or allergies to avocados, kiwis, nuts, or bananas. Because latent allergens in the ambient air can cause respiratory or anaphylactic symptoms among persons with latex hypersensitivity, patient appointments should be scheduled for the first appointment of the day. This minimizes exposure to airborne latex particles. In addition, the dentist should communicate with other dental health care providers regarding a latex allergy. This will prevent them from bringing latex-containing materials into the treatment area.
Dental facilities should educate dental health care providers regarding the signs, symptoms, and diagnoses of skin reactions associated with frequent hand hygiene and glove use. Dental patients should be screened for latex allergy and referred for medical consultation if necessary. If a patient or dental health care provider has a latex allergy, make certain that the environment is as latex free as possible. Emergency treatment kits with latex-free products should also be readily available for use.
Patient care items such as dental instruments, devices, and equipment are categorized as critical, semi critical, or non critical, depending on the potential risk for infection associated with their intended use.
Critical and semi-critical items should be sterilized by heat. If a semi-critical item is heat-sensitive, it should at a minimum, be processed with a high level disinfection technique. Non critical patient care items pose the least risk of transmission of infection, and can actually serve as an effective barrier to microorganisms. In the majority of cases, cleaning, or if visibly soiled, cleaning followed by disinfection with an EPA registered hospital disinfectant is adequate. When the item is visibly contaminated with blood or other potentially infectious materials, an EPA registered intermediate level hospital disinfectant should be applied. If cleaning or disinfecting certain non critical patient care items causes damage to the surface, the use of a disposable barrier protection is often the better alternative.
Dentists should use only FDA approved medical devices for sterilization and follow the manufacturer's instructions for correct use. Both critical and semi critical dental instruments should be cleaned and heat sterilized before each use. Packages should be allowed to dry thoroughly in the sterilizer before they are handled, in order to avoid contamination. Heat sensitive critical and semi critical instruments should be sterilized by using FDA approved sterilant/high level disinfectants or an FDA approved low temperature sterilization method. The use of single use disposable instruments is an acceptable alternative if they are used once and disposed of accordingly. The use of liquid chemical sterilants/high level disinfectants for environmental surface disinfection or as holding solutions is not recommended.
Dentists must ensure that non critical patient care items are barrier protected or cleaned. If they become visibly soiled, they should be cleaned and disinfected after each use with an EPA-registered hospital disinfectant. If visibly contaminated with blood, the use of an EPA-registered intermediate level hospital disinfectant is recommended.
In the dental operatory, surfaces or equipment that does not contact the patient directly can become contaminated when the dentist administers dental treatment. Clinical contact surfaces can be contaminated from patient materials either by direct spray or the splatter generated during dental procedures or by contact with dental health care provider's gloved hands. Although they have not been associated directly with the transmission of infection to either dental health care providers or patients, frequently touched surfaces in a dental facility can serve as reservoirs of microbial contamination. The transfer of microorganisms from contaminated surfaces to patients primarily occurs through the dentist's hand contact. When these surfaces are touched, microbial agents are transferred to instruments, other surfaces, or to the nose, mouth, or eyes of workers or patients. Examples of these surfaces include light handles and switches, dental radiograph equipment, dental chair side computers, drawer and faucet handles, countertops, pens, telephones, and doorknobs. Although hand hygiene is key to minimizing this transferal, barrier protection or cleaning and disinfecting of environmental surfaces also protects against health care associated infections.
Cleaning is the necessary first step of any disinfection process, as it is a form of decontamination. Decontamination renders surfaces safe by removing organic matter, salts, and visible soils, all of which interfere with microbial inactivation. The physical action of scrubbing with detergents and surfactants and rinsing with water removes substantial numbers of microorganisms. If a surface is not cleaned first, the success of the disinfection process can be compromised. Removal of all visible blood and inorganic and organic matter can be as critical as the germicidal activity of the disinfecting agent. When a surface cannot be cleaned adequately, it should be protected with barriers.
Barrier protection of surfaces and equipment can prevent contamination of clinical contact surfaces, but is particularly effective for those that are difficult to clean. Barriers include clear plastic wrap, bags, sheets, tubing, and plastic-backed paper or other materials impervious to moisture. Because such coverings can become contaminated, they should be removed and discarded between patients, while the dentist is still gloved. After removing the barrier, the surface should be examined to make sure it did not become inadvertently soiled. The surface needs to be cleaned and disinfected only if contamination is evident, otherwise after removing gloves and performing hand hygiene, the dentist can place clean barriers on these surfaces in preparation for the next patient. If barriers are not used, surfaces should be cleaned and disinfected between patients by using an EPA registered hospital disinfectant with a low or intermediate level disinfectant. Intermediate level disinfectant should be used when the surface is visibly contaminated with blood or other potentially infectious material.
Dentists should use surface barriers to protect clinical contact surfaces, particularly those that are difficult to clean, such as the switches on dental chairs, and change surface barriers between patients. If a surface is not barrier protected, it should be cleaned and disinfected using an EPA registered hospital disinfectant with a low to intermediate level claim activity, after each patient. If the surface is visibly contaminated with blood, the use of an intermediate-level disinfectant is recommended.
Evidence does not support that housekeeping surfaces such as floors, walls, and sinks, pose a risk for disease transmission in dental health care settings. The actual, physical removal of microorganisms and soil by wiping or scrubbing is probably as critical, if not more so, than any antimicrobial effect provided by the agent used. The majority of housekeeping surfaces need to be cleaned only with a detergent and water or an EPA registered hospital disinfectant/detergent, depending on the nature of the surface and the type and degree of contamination.
Floors should be cleaned regularly, and spills should be cleaned up promptly. If there is uncertainty regarding the nature of the soil on the surface, an EPA registered hospital disinfectant or detergent designed for general housekeeping purposes should be used in the patient care area. Unless contamination is reasonably anticipated or apparent, cleaning or disinfecting walls, window drapes, and other vertical surfaces is unnecessary. However, when housekeeping surfaces are visibly contaminated by blood or other potentially infectious materials, prompt removal and surface disinfection is appropriate infection-control practice and required by OSHA.
The majority of blood contamination events in dentistry result from splatter during dental procedures which use rotary or ultrasonic instrumentation. Although no evidence supports Hepatitis B, Hepatitis C, or HIV being transmitted from a housekeeping surface, prompt removal and surface disinfection of an area contaminated by either blood or other potentially infectious material is an appropriate infection control practice and required as part of OSHA Safety Program guidelines.
Blood or other potentially infectious materials that is spilled should be cleaned and the surface decontaminated with an EPA registered hospital disinfectant with a low to intermediate-level activity. The disinfectant level is dependent upon the size of the spill and the surface porosity.
Since carpeting is more difficult to clean than nonporous hard-surface flooring, it cannot be reliably disinfected, especially after spills of blood and body substances. Studies have documented the presence of diverse microbial populations, primarily bacteria and fungi, in carpeting. Cloth furnishings pose similar contamination risks in areas of direct patient care and places where contaminated materials are managed, such as the dental operatory, laboratory, or instrument processing areas. For these reasons, use of carpeted flooring and fabric-upholstered furnishings in these areas should be avoided
The dentist office should not contain carpeting and cloth-upholstered furnishings in the dental operatories, laboratories, and instrument processing areas. Carpeting is more difficult to clean than nonporous hard-surface flooring, and it cannot be reliably disinfected, especially after spills of blood and body substances. Studies have documented the presence of diverse microbial populations, primarily bacteria and fungi, in carpeting. Cloth furnishings pose similar contamination risks in areas of direct patient care and places where contaminated materials are managed. For these reasons, use of carpeted flooring and fabric-upholstered furnishings in these areas should be avoided.
General waste from hospitals, dental practices or clinical/research laboratories, is no more infective than residential waste. Most soiled items in dental offices are considered general medical waste and can be disposed of with ordinary waste. Examples of this type of waste include used gloves, masks, gowns, lightly soiled gauze or cotton rolls, and environmental barriers such as plastic sheets or bags, used to cover equipment during treatment.
Dental facilities must develop a medical waste management program which follows federal, state, and local regulations. Dental health care providers who handle and dispose of regulated medical waste must be trained in appropriate handling and disposal methods and informed of the possible health and safety hazards.
Studies have demonstrated that dental unit waterlines used with high speed handpieces, air/water syringes, and ultrasonic scalers, can become colonized with microorganisms, including bacteria, fungi, and protozoa. These microorganisms colonize and replicate on the interior surfaces of the waterline tubing and form a biofilm, which serves as a reservoir that can amplify the number of free-floating microorganisms in water used for dental treatment.
Researchers have not demonstrated a measurable risk of adverse health effects among dental health care providers or patients from exposure to dental water. Certain studies determined that dental health care providers had altered nasal flora or substantially greater titers of Legionella antibodies in comparisons with control populations; however, no cases of legionellosis were identified among exposed dental health care providers. Contaminated dental water might have been the source for localized Pseudomonas aeruginosa infections in two immunocompromised patients. Although transient carriage of P. aeruginosa was observed in 78 healthy patients treated with contaminated dental treatment water, no illness was reported among the group. In this same study, a retrospective review of dental records also failed to identify infections.
Concentrations of bacterial endotoxin less than 1,000 endotoxin units/mL from gram-negative water bacteria have been detected in water from colonized dental units. No standards exist for an acceptable level of endotoxin in drinking water, but the maximum level permissible in United States Pharmacopeia (USP) sterile water for irrigation is only 0.25 endotoxin units/mL. Although the consequences of acute and chronic exposure to aerosolized endotoxin in dental health care settings has not been investigated, endotoxin has been associated with exacerbation of asthma and onset of hypersensitivity pneumonitis in other occupational settings.
Research has demonstrated that microbial counts can reach less than 200,000 colony-forming units (CFU)/mL within 5 days after installation of new dental unit waterlines, and levels of microbial contamination less than 106 CFU/mL of dental unit water have been documented. These counts can occur because dental unit waterline factors such as system design, flow rates, and materials,promoted both bacterial growth and development of biofilm.
Although no epidemiologic evidence indicates a public health problem, the presence of substantial numbers of pathogens in dental unit waterlines generates concern. Exposing patients or dental health care providers to water of uncertain microbiological quality, despite the lack of documented adverse health effects, is inconsistent with accepted infection control principles. Therefore, in 1995, the ADA addressed the dental water concern by requesting that manufacturers provide equipment with the ability to deliver treatment water with less than 200 CFU/mL of unfiltered output from waterlines. This threshold was based on the quality assurance standard established for dialysate fluid. This threshold ensured that fluid delivery systems in hemodialysis units had not been colonized by indigenous waterborne organisms.
In 1993, the CDC recommended that dental waterlines be flushed at the beginning of the clinic day to reduce the microbial load. However, studies have demonstrated this practice does not affect biofilm in the waterlines or reliably improve the quality of water used during dental treatment. Because the recommended value of less than 500 CFU/mL cannot be achieved by using this method, other strategies need to be used. Dental unit water that remains untreated or unfiltered is not likely to meet drinking water standards. Commercial devices and procedures designed to improve the quality of water used in dental treatment are available and the methods shown to be effective include self-contained water systems combined with chemical treatment, in-line microfilters, or a combination of these treatments. Simply using source water containing less than 500 CFU/mL of bacteria such as tap, distilled, or sterile water, in a self-contained water system will not eliminate bacterial contamination in treatment water if biofilms in the water system are not controlled. The removal or inactivation of dental waterline biofilms requires the use of chemical germicides.
Patient material such as oral microorganisms, blood, and saliva can enter the dental water system during patient treatment. Dental devices that are connected to the dental water system and enter the patient's mouth, should be operated to discharge water and air for a minimum of 20--30 seconds after each patient is seen. This procedure is intended to physically flush out patient material that might have entered the turbine, air, or waterlines. The majority of recently manufactured dental units are engineered to prevent retraction of oral fluids, but some older dental units are equipped with anti-retraction valves that require periodic maintenance. Even with anti-retraction valves, flushing devices for a minimum of 20--30 seconds after each patient is recommended.
Dental health care providers should be trained regarding water quality, biofilm formation, water treatment methods, and the use of appropriate maintenance protocols for water delivery systems. Water treatment and monitoring products require strict adherence to maintenance protocols, and noncompliance with treatment regimens has been associated with the persistence of microbial contamination in treated systems. Clinical monitoring of water quality can ensure that procedures are correctly performed, and that devices are working in accordance with the manufacturer's validated protocol.
Sterile saline or sterile water should be used as a coolant/irrigation in oral surgery procedures. Oral surgery procedures present a greater opportunity for microorganisms to enter into the vascular system and other sterile areas that support the oral cavity and potential exists for localized or systemic infection. Conventional dental units cannot reliably deliver sterile water, even when equipped with independent water reservoirs. This is because the water-bearing pathway of a conventional dental unit cannot be reliably sterilized. Delivery devices such as bulb syringe or sterile, single-use disposable products, should be used to deliver sterile water. Oral surgery and implant hand pieces, as well as ultrasonic scalers, are commercially available to bypass the dental unit and deliver sterile water or other solutions. These items use a single-use disposable or sterilizable tubing design.
A boil-water advisory is a public health announcement that requires that water be boiled prior to drinking. When issued, it usually indicates that the water is unsafe for drinking. In recent years, increased numbers of boil-water advisories have resulted from contamination of public drinking water systems with waterborne pathogens.
During a boil-water advisory, water should not be delivered to patients through the dental unit, ultrasonic scaler, or other dental equipment that uses the public water system. This restriction does not apply if the water source is isolated from the municipal water system and a separate water reservoir or other water treatment device cleared for marketing by FDA is used. Until a boil-water advisory is cancelled, dental patients should rinse with bottled or distilled water.
Dental treatment water should meet EPA regulatory standards for drinking water. After a dental patient is treated, any device that is connected to the water system that entered the patient's mouth should be discharged of water and air for a minimum of 20--30 seconds.
When a boil-water advisory is in effect, water should not be delivered from the public water system to the patient through the dental operative unit, ultrasonic scaler, or other dental equipment that uses the public water system. In addition to treatment, water from the public water system should not be used for patient rinsing, or hand washing purposes. Dentists should use antimicrobial-containing products that do not require water to wash their hands. If the hands are visibly contaminated, they should use bottled water and soap or an antiseptic towelette.
After boil-water advisory has ended, dentists should follow guidance given by the local water utility regarding adequate flushing of waterlines. If no guidance is provided, they should disinfect and flush dental waterlines and faucets for 1--5 minutes before using the device for patient care.
Multiple semi critical dental devices which touch the mucous membranes are attached to the air or waterlines of the dental unit. Among these devices are high and low speed hand pieces, prophylaxis angles, ultrasonic and sonic scaling tips, air abrasion devices, and air and water syringe tips. Although no epidemiologic evidence implicates these instruments in disease transmission, studies of high speed hand pieces using dye expulsion have confirmed that retracting oral fluids have the potential to enter into the internal compartments of the device. This indicates that patient material that is retained in the device can be expelled intraorally during subsequent uses. Studies using laboratory models also indicate the possibility for viral DNA and viable virus to be retained inside high speed hand pieces and prophylaxis angles.
The potential for the internal surfaces of devices such as low-speed hand pieces and ultrasonic scalers being contaminated, has not been studied, but their physical access is restricted and in turn, limits the ability to clean them. This being the case,, any dental device connected to the dental air/water system that enters the patient's mouth should be discharged of water, air, or both, for a minimum of 20--30 seconds after each patient is treated. This will help to physically flush out any patient materials that may have entered the turbine and air and waterlines.
Components of dental instruments that are permanently attached to dental unit waterlines, while they do not enter the patient's oral cavity, can become contaminated with oral fluids during treatment procedures. Components such as handles or dental unit attachments of saliva ejectors, high-speed air evacuators, and air/water syringes, should be covered with approved barriers that are changed after each use. If the item becomes visibly contaminated during use, it should be cleaned and disinfected by the dental health care provider with an EPA-registered intermediate level hospital disinfectant before the next patient is treated.
Backflow can occur from low volume saliva ejectors when the pressure in the patient's mouth is less than that of the evacuator. Studies have shown that backflow in low volume suction lines occurs and microorganisms are present in the lines retracted into the patient's mouth when a seal around the saliva ejector is created. This seal could be created when a patient closes their lips around the tip of the ejector, creating a partial vacuum, which in turn, creates a potential source of cross contamination. Studies have also demonstrated that gravity pulls fluid back toward the patient's mouth whenever the suction tubing holding the tip is positioned above the patient's mouth, or during simultaneous use of other high volume evacuation equipment. Although no adverse health effects have been reported with the use of saliva ejectors, dentists and patients should be aware, that in certain situations, backflow could occur when its use.
Dental hand pieces and other intraoral instruments that can be removed from dental units should, following manufacturer's instructions, be clean and sterilized between patient use. that can be removed from the air and waterlines of dental units between patients. The use of surface disinfectants, liquid chemical sterlants or ethylene oxide should not be used on these items.
Dental patients should not close their lips tightly around the tip of the saliva ejector to evacuate oral fluids. This can cause a backflow of harmful contaminants.
When a dentist takes dental X-rays, there is a high potential for cross-contamination to occur between blood and saliva with equipment and dental surfaces. Dental health care providers should always wear gloves when taking radiographs and handling contaminated film packets. Other personal protection equipment should also be worn if spattering of blood or other body fluids is likely to occur. Heat tolerant intraoral radiograph accessories, such as film-holding and positioning devices, should be used and heat sterilized after treating each patient.
Digital radiography sensors and other high-tech dental instruments which come into contact with mucous membranes are considered semi critical devices. Semi critical devices should be cleaned and heat-sterilized, or undergo a high level disinfectant process between patients. However, these items vary by manufacturer or type of device in their ability to be sterilized or disinfected. Semi critical items that can be neither heat sterilized or high level disinfected should, at a minimum, be barrier protected using an FDA approved barrier. This is to reduce the possibility of gross contamination during dental treatment. Unfortunately, barrier use does not always protect from contamination. One study found that a brand of commercially available plastic barriers used to protect dental digital radiography sensors had a substantial failure rate of 44%. This rate dropped to 6% when latex finger cots were used with the plastic barriers. In order to minimize the potential for device associated infections when using barriers, the device should be cleaned and intermediate level disinfected, after the barrier is removed.
Dental health care providers should wear gloves when exposing radiographs and handling contaminated film packet and use heat-tolerant or disposable intraoral devices whenever possible. Radiographs should be transported and handled in an aseptic manner to prevent contamination of the developing equipment. Dental devices should be cleaned and disinfected between patients.
Dentist's should clean and heat-sterilize, or high level disinfect, barrier protected semi critical items. If the item cannot tolerate these procedures, then, at a minimum, they should be cleaned and disinfected with an EPA-registered hospital intermediate level disinfectant. This should occur between each dental patient. If digital radiology sensors and associated computer hardware is used, follow the manufacturers instructions for cleaning to remove contaminants.
Dentists must handle medications and fluid infusion systems safely to prevent health care associated infections among patients undergoing conscious sedation. Sedation medications that are packaged in single-dose ampules, vials or prefilled syringes, is intended for use on a single patient. Single-dose vials might pose a risk for contamination if they are punctured repeatedly. The leftover contents should be discarded and never combined with medications for use on another patient, even if the needle on the syringe is changed.
Multidose vials are used for more than one patient and usually have a preservative. Regardless of whether it is single or multiuse, all medication must be handled safely to prevent contamination. The overall risk for extrinsic contamination of multidose vials is probably minimal, although the consequences can result in a life threatening infection. When using a multidose vial, its access diaphragm should be cleansed with 70% alcohol before inserting the sterile device into the vial. A multidose vial should be discarded if sterility is ever compromised.
Medication vials, syringes, or supplies should not be carried in uniform or clothing pockets. If trays are used to deliver medications to individual patients, they should be cleaned between patients. To further reduce the chance of contamination, all medication vials should be restricted to a centralized medication preparation area separate from the treatment area.
The use of a single dose vial for patient medicating is recommended. Dentists should never administer medication from a syringe to multiple patients, even if the needle on the syringe is changed. After use, the contents of a single use vial should be discarded promptly.
When using mulidose vials, the access diaphragm should be cleansed with 70% alcohol before the device is inserted into the vial. Both the needle and syringe used to access the multidose vial should be sterile. A syringe should never be reused, even if the needle is changed.
Multidose vials should be kept away from the immediate patient treatment area, in order to prevent inadvertent contamination by spray or spatter. They should also be discarded if sterility is compromised.
A single use device, also called a disposable device, is designed to be used on one patient and then discarded. Single-use devices in dentistry are usually not heat tolerant and cannot be reliably cleaned. Examples include syringe needles, prophylaxis cups and brushes, and plastic orthodontic brackets. Other items such as prophylaxis angles, saliva ejectors, high-volume evacuator tips, and air/water syringe tips are commonly available in a disposable form and should be disposed of appropriately after each use. Single-use devices and items used during oral surgical procedures, such as cotton rolls, gauze and irrigating syringes, should be sterile at the time of use.
Dentists are to use single-use devices for one patient only and dispose of them appropriately.
The antimicrobial mouth rinses used by dental patients before a dental procedure are intended to reduce the number of microorganisms that may be released from the patient in the form of aerosols or spatter. These microorganisms can subsequently contaminate the dental health care provider and dental equipment operatory surfaces. Also, prerinsing can decrease the number of microorganisms that are introduced into the patient's bloodstream during invasive dental procedures.
No scientific evidence indicates that preprocedural mouth rinsing prevents clinical infections among dental health care providers or patients. There have been studies which demonstrated that preprocedural rinses with an antimicrobial product reduced the level of oral microorganisms found in the aerosols and spatter generated during routine dental procedures with rotary instruments. Preprocedural mouth rinses can beneficial before dental procedures in which a prophylaxis cup or ultrasonic scaler is used. These procedures cannot use rubber dams, which have also been shown to minimize aerosol and spatter.
Preprocedural Mouth Rinses - OSHA Safety Program Recommendations
No recommendation is offered regarding use of preprocedural antimicrobial mouth rinses to prevent clinical infections among dental health care providers or patients. Although studies have demonstrated that a preprocedural antimicrobial rinse can reduce the level of oral microorganisms in aerosols and spatter generated during routine dental procedures and can decrease the number of microorganisms introduced in the patient's bloodstream during invasive dental procedures, the scientific evidence is inconclusive that using these rinses prevents clinical infections among DHCP or patients.
Because the oral cavity is colonized with numerous microorganisms, oral surgical procedures present an opportunity for entry of microorganisms into the vascular system and other normally sterile areas of the oral cavity. Therefore, an increased potential exists for localized or systemic infection.
Oral surgeons should perform surgical hand antisepsis by using an antimicrobial product before applying sterile surgeon's gloves. The use of a sterile saline or sterile water as a coolant/irrigatant when performing oral surgical procedures is also recommended for use with devices specifically designed for delivering sterile irrigating fluids.
Dental prostheses, appliances, and items used in their fabrication such as impressions, occlusal rims, and bite registrations, are potential sources for cross-contamination. Dental health care providers should handle these items in a manner that prevents exposure to themselves, their patients, and the office environment to infectious agents. Effective communication and coordination between the dental laboratory and the dental practice will ensure that appropriate cleaning and disinfection procedures are performed in each respective area, materials are not damaged or distorted by disinfectant overexposure, and that disinfection procedures between the offices are not duplicated.
Dental prostheses or impressions brought into the laboratory can be contaminated with bacteria, viruses, and fungi. These items should be thoroughly cleaned, disinfected with an EPA-registered hospital disinfectant, and thoroughly rinsed before being handled in an in office laboratory or sent to an off site laboratory. The best time to clean and disinfect impressions, prostheses, or appliances is as soon as possible after removal from the patient's mouth before drying of blood or other bioburden can occur.
In the laboratory, a separate receiving and disinfecting area should be established to reduce contamination in the production area. Bringing untreated items into the laboratory increases chances for cross infection. If no communication has been received regarding prior cleaning and disinfection of a material from the dental office, the dental laboratory staff should perform cleaning and disinfection procedures before handling the item. If a previously undetected area of blood or bioburden becomes apparent, cleaning and disinfection procedures should be repeated by the dental laboratory. Transfer of oral microorganisms into and onto impressions has been documented, as well as movement of these organisms onto dental casts. Certain microbes have been demonstrated to remain viable within gypsum cast materials for less than 7 days. Incorrect handling of contaminated impressions, prostheses, or appliances, therefore, offers an opportunity for transmission of microorganisms.
Appliances and prostheses that are delivered to the patient should be free of contamination. Communication between the laboratory and the dental practice is very important prior to delivery, as it determines which area is responsible for the final disinfection process. If the dental laboratory staff provides the disinfection, written documentation of the disinfection method should be provided, and the item placed in a tamper-evident container before returning it to the dental office. If no documentation is provided, then the dental office is responsible for final disinfection procedures.
The use of personal protection equipment when handling items received in the laboratory until they have been decontaminated is highly recommended. Before handling, dental prosthesis and prosthodontic materials should be rinsed with an EPA registered intermediate level hospital disinfectant. Information regarding the disinfection techniques used should be documented accordingly. This includes the sending and receiving of laboratory cases.
During surgical procedures that use a laser or electrosurgical unit, the thermal destruction of tissue creates a smoke byproduct. Laser plumes or surgical smoke represent another potential risk for dental health care providers. Lasers transfer electromagnetic energy into tissues, resulting in the release of a heated plume that includes particles, gases, tissue debris, viruses, and offensive odors. One concern is that aerosolized infectious material in the laser plume might reach the nasal mucosa of the laser operator and adjacent dental health care provider. Although certain viruses, such as herpes simplex virus, appear not to aerosolize efficiently, other viruses and various bacteria, such as human papilloma virus or HIV, have been detected in laser plumes. However, the presence of an infectious agent in a laser plume might not be sufficient to cause disease from airborne exposure, especially if the agent's normal mode of transmission is not airborne.
No evidence indicates that HIV or Hepatitis B have been transmitted through aerosolization and inhalation. Although continuing studies are needed to evaluate the risk to the dental health care provider of laser plumes and electrosurgery smoke, following recommendations and practices may be the practical way to minimize the risk. These practices include using standard precautions, central room suction units with in-line filters to collect particulate matter, and having smoke exhaust systems which contain a high efficiency filter to remove large amounts of laser plume particles. Local smoke evacuation systems have been recommended by consensus organizations, as a means of improving the field quality. Laser smoke is an emerging problem, yet the concern remains unresolved in dental practices.
The OSHA Safety Program offers no recommendation regarding practices to reduce dental health care providers' exposure to laser plumes/surgical smoke when dental lasers are used, as the concern is unresolved. Therefore, the effect of the exposure on dental health care providers from laser use has not been adequately evaluated.
Health care facility practices to reduce health care providers' exposure to laser plume smoke has been offered. Suggestions includes the use of standardized precautions, as well as, central room suction units to collect matter from minimal plumes and dedicated smoke exhaust systems to remove laser-plume particles.
Patients infected with M. tuberculosis occasionally seek urgent dental treatment at outpatient dental settings. Understanding the pathogenesis of the development of TB helps dental health care providers with better patient management.
M. tuberculosis is a bacterium that is carried in airborne infective droplet nuclei that generates when persons with pulmonary or laryngeal TB sneeze, cough, speak, or sing. These small particles can stay suspended in the air for hours. Infection occurs when a susceptible person inhales droplet nuclei which contain M. tuberculosis, which then travels to the alveoli of the lungs. Within 2 to 12 weeks after the initial infection with M. tuberculosis, the immune response usually prevents further spread of the bacteria. While further spreading is prevented, the bacteria can often remain alive in the lungs for years, becoming known as a latent TB infection. Persons with latent TB infections usually show a positive reaction to tuberculin skin tests (TST), yet have no symptoms of active disease, and are not infectious. However, an active disease can develop later in life if no treatment is received for the latent infection.
Approximately 5% of persons who have been recently infected and not treated for latent TB infection will progress from infection to active disease during the first 1 to 2 years after infection; another 5% will develop the active disease years later. Thus, approximately 90% of U.S. persons with latent TB infection do not progress to active TB disease. While both latent TB infection and active TB disease are described as TB, only the person with active disease is contagious and presents a risk of transmission. Symptoms of active TB disease include a productive cough, night sweats, fatigue, malaise, fever, and unexplained weight loss. Certain medical conditions such as HIV, increases the risk that a TB infection will progress to active disease at a faster rate.
The risk for exposure to TB for dental health care providers by a patient with active TB disease is probably low. There is only one report that exists of a TB transmission in a dental facility. In addition, among dentists, the TST conversion rate is also low. However, dental health care providers, or the community served by the dental facility may be at relatively high risk for exposure to TB. Because surgical masks do not prevent inhalation of M. tuberculosis droplet nuclei, standard precautions are not sufficient to prevent transmission of this organism.
The transmission of TB is controlled through a hierarchy of measures, including administrative and environmental controls, as well as personal respiratory protection. The main administrative goals of a TB infection control program are early detection of an individual with active TB and prompt isolation to reduce the risk of transmission. Although dental health care providers are not responsible for diagnosis and treatment of TB, because the potential for transmission exists in outpatient settings, they should be trained to recognize signs and symptoms to help with prompt detection. The dental practices should develop a TB control program appropriate for their level of risk.
Dentists should be educated to recognize the signs, symptoms, and transmission of TB. Each dental patient should be assessed during the medical history data gathering stage.
Dental facilities should conduct baseline TSTs for all dental health care providers, since outpatient settings pose a high risk of transmission. Facilities should also develop, maintain and implement a written TB infection control plan, following CDC recommendation. It should incorporate a community risk assessment to guide employee TSTs and follow-up needs, as well as managing dental health care providers with the TB disease.
When active TB is suspected, dentists should evaluate the patient in isolation, away from other patients and dental health care providers. When not being evaluated, the patient should wear a surgical mask or be instructed to cover mouth and nose when coughing or sneezing. Any elective dental treatment should be postponed until the patient is noninfectious. If urgent dental treatment is needed, the dental patient should be referred to a facility with TB engineering controls and a respiratory protection program.
Creutzfeldt-Jakob disease (CJD) belongs to a group of rapidly progressive, fatal, degenerative neurological disorders, transmissible spongiform encephalopathies (TSEs) which affect both humans and animals. CJD is thought to be caused by infection with a pathogen called a prion. Prions are isoforms of a normal protein and a prion disease has an incubation period of years and is usually fatal within a year of being diagnosed.
Among humans, TSEs include CJD, Gerstmann-Straussler-Scheinker syndrome, fatal familial insomnia, kuru, and variant CJD (vCJD). CJD occurs in sporadic, familial, and acquired forms, and has an annual incidence in the US and other countries of approximately 1 case/million population. In approximately 85% of affected patients, CJD occurs as a sporadic disease with no recognizable pattern of transmission. A smaller proportion of patients (5%--15%) experience familial CJD because of inherited mutations of the prion protein gene.
vCJD is distinguishable clinically and neuropathologically from classic CJD, and strong evidence indicates that is has a causal relationship with bovine spongiform encephalopathy (BSE), commonly known as mad cow disease. vCJD was reported first in the UK in 1996 and subsequently in other European countries. Only one case of vCJD has been reported in the US, in an immigrant from the UK. Compared with CJD patients, those with vCJD tend to be younger (28 years vs. 68 years median age at death), and have a longer duration of illness (13 months vs. 4.5 months). Also, vCJD patients characteristically exhibit sensory and psychiatric symptoms that are uncommon with CJD. Another difference includes the ease with which the presence of prions is consistently shown in lymphoreticular tissues such as the tonsil of vCJD patients.
Both CJD and vCJD are transmissible diseases, but not through the air or casual contact. All known cases of iatrogenic CJD have resulted from exposure to infected central nervous tissue, pituitary, or eye tissue. While experiments with animals showed that other tissues have low or no detectable infectivity, and that a TSE in sheep could be transmitted to healthy hamsters and mice by exposing the oral tissues to infectious homogenate, these experiments did not directly apply to human transmission and clinical dentistry. Therefore, the position is that a theoretical risk of transmitting prion diseases through perioral exposures exists.
According to published reports, iatrogenic transmission of CJD has occurred in humans under three circumstances: after using contaminated electroencephalography depth electrodes and neurosurgical equipment, after using extracted pituitary hormones; and after implantation of contaminated corneal and dura mater grafts from humans. The equipment related cases occurred before the sterilization procedures were implemented in health care facilities. Case control studies found no evidence that dental procedures increased the risk of iatrogenic transmission of TSEs among humans or that CJD transmission was associated with dental procedures.
Prions show unusual resistance to conventional chemical and physical decontamination procedures. Considering this resistance and the invariably fatal outcome of CJD, procedures for disinfecting and sterilizing instruments that have been potentially contaminated with the CJD prion has caused years of controversy. While scientific data indicates a risk, sporadic CJD transmission during dental and oral surgical procedures is low to nil. Until additional information is available regarding the transmissibility of CJD or vCJD, special precautions should be taken when dental health care providers are treating known CJD or vCJD patients.
Special precautions would involve the dentist using single-use disposable items and equipment whenever possible. This would also include considering such items that would usually undergo a sterilization process, such as endodontic files, broaches, and carbide and diamond burs, as single use disposables and discarding them after one use. Any dental instruments that are used on the patient should be kept moist until it is cleaned and decontaminated. This is to minimize the drying of tissues and body fluids on the dental device. When undergoing sterilization, the method recognized by the World Health Organization should be followed. This involves cleaning instruments thoroughly and steam autoclaving them at 134ºC for 18 minutes. Finally, dentists should not use flash sterilization for processing instruments or devices, while the potential infectivity of oral tissues in CJD or vCJD patients remains an unresolved concern.
The OSHA Safety Program offers no recommendations regarding use of special precautions, in addition to standard precautions when treating known CJD or vCJD patients. Potential infectivity of oral tissues in CJD or vCJD patients is an unresolved issue. While scientific data indicates the risk of sporadic CJD, transmission during dental and oral surgical procedures is low to nil. Until additional information become available regarding the transmissibility of CJD or vCJD during dental procedures, special precautions, in addition to standard precautions should be followed when treating known CJD or vCJD patients.