Principle 1: Take Action to Stay Healthy

All persons must take positive steps to maintain their own health. This is especially true for persons working in any healthcare setting, including DHCP.

Immunizations for vaccine-preventable diseases

Hand hygiene

Postexposure management

Education and training of DHCP

Principle 2: Avoid Contact with Blood and Other Infectious Body Substances

Avoid contact with blood and other potentially infectious body fluids by using a combination of safe work practices and behaviors and engineering controls. Infection-prevention and infection-control measures include:

Effective use of personal protective equipment (PPE) (e.g., gloves, face masks, protective eyewear, protective gowns) (Figure 7-1)

Safe handling of sharp instruments and objects

Figure 7-1 Personal protective equipment worn by dental hygienist.

Principle 3: Make Client Care Items (Dental Instruments, Devices, and Equipment) Safe for Use

Instruments, devices, and equipment used to provide direct client care become contaminated. Appropriate infection-control measures must be taken to prevent transmission of infectious agents from client to client through these contaminated items. Methods of appropriate infection-control measures include the following:

Cleaning, sterilization, or disinfection of reusable client care items

Appropriate containment and disposal of all single-use items

Principle 4: Limit the Spread of Blood and Other Infectious Body Substances

Although environmental surfaces and waste products are less likely to provide an efficient mechanism for transmission of infectious agents, they are subject to contamination in oral healthcare settings. Examples of infection-control measures to limit the spread of contamination include:

Environment infection control

○ Protective surface covers or barriers (Figure 7-2)

○ Cleaning and surface disinfection

Effective management of regulated waste

○ Nonsharp infectious waste

○ Sharps

○ Hazardous waste

Figure 7-2 Equipment barriers (arrows) on dental light.

Immunizations for Vaccine-Preventable Diseases

Immunization is one of the most effective means of preventing disease transmission. Once a person has acquired immunity through vaccination, the disease no longer poses a threat. In addition to standard childhood immunizations, hygienists should obtain immunizations specifically recommended for HCP. The CDC Advisory Council on Immunization Practices (ACIP) routinely reviews, updates, and revises immunization recommendations. It is therefore important to use the most current ACIP recommendations when making immunization decisions (Table 7-1).

TABLE 7-1 Immunizations Strongly Recommended for Healthcare Personnel (HCP)

HCP in specific geographic locations or with underlying medical conditions may need immunizations in addition to those currently recommended by the CDC. It is important for each individual to consult with his or her physician to determine which immunizations are appropriate based on disease risk in the specific location. All children in the United States and most other countries receive immunization for diphtheria, pertussis, and tetanus (DPT) as a combined vaccine. Of these, tetanus and pertussis require boosters later in life. Additional vaccines recommended for all HCP include hepatitis B, influenza, measles, mumps, rubella, and varicella unless the healthcare worker has naturally acquired immunity stemming from a past infection. In addition, the CDC recommends pneumococcal vaccine for all adults age 65 or older. CDC also recommends annual influenza vaccine for all healthcare personnel. OSHA requires employers to offer all personnel at risk of exposure to blood and other potentially infectious materials HBV vaccination unless they have verification of previous hepatitis B immunization or are infected with HBV. If the employee declines immunization, he or she must sign a specific OSHA-designated declination waiver (Figure 7-3). The vaccination is in a three-part series with a recommendation for post-titer testing 1 to 2 months after the third dose of vaccine. Persons who fail to respond should be offered a second three-dose series; when completed, the titer is retested for antibody response. Those who fail to develop detectable antibodies to hepatitis B surface antigen (anti-HBs) after six doses should be considered nonresponders and tested for hepatitis B surface antigen (HBsAg), which indicates active infection or carrier status. If the result of this test is negative, the individual is considered as susceptible to HBV infection and counseled on precautions to avoid exposure and appropriate postexposure management.

Figure 7-3 Required hepatitis B virus vaccine declination form.

Work Restrictions

DHCP should be aware of their personal health and take action to stay healthy. Within a written infection-control plan it is necessary to discuss those conditions that require a restriction or exclusion from direct patient care. The U.S. Public Health Service recommends work restrictions for HCP with specific infections and following exposure to some diseases (Table 7-2). Many of these infections are preventable with vaccines. The following precautions help protect HCP and clients:

HCP diagnosed with diphtheria should refrain from working until the illness resolves.

HCP with mumps or measles should refrain from working during the acute illness phase, as well as after exposure and during the incubation phase if not immunized.

HCP diagnosed with hepatitis A should refrain from direct client contact and avoid handling food others will eat.

HCP with an upper respiratory infection should avoid contact with medically compromised persons as defined by the ACIP for complications from influenza.

HCP with active herpes zoster (shingles) may continue to work unrestricted but should cover lesions to protect against exposure of nonintact skin to blood and body fluids.

For HCP identified as HBV e-antigen carriers, the CDC recommends that an expert review panel determine restrictions necessary for certain types of invasive procedures. The e-antigen is associated with a higher risk of transmission from HCP to client in spite of standard precautions. Any healthcare worker who is a hepatitis B e-antigen carrier should consult with a physician to determine status and explore options for treatment and concerns for client safety.

HCP with HIV are not specifically restricted, but it is possible that some modifications would be necessary for certain procedures. An expert review panel and physician should be consulted.

TABLE 7-2 Work Restriction Guidelines for Healthcare Personnel with Infectious Diseases

∗ Unless epidemiologically linked to transmission of disease.

† Those susceptible to varicella and who are at increased risk of complications of varicella (e.g., neonates and immunocompromised persons of any age).

‡ Patients at high risk as defined by ACIP for complications of influenza.

Adapted from Bolyard EA: Hospital Infection Control Practices Advisory Committee. Guidelines for infection control in health care personnel, 1998, Am J Infect Control 26:289, 1998. Adapted from recommendations of the Advisory Committee on Immunization Practices (ACIP).

It is important to consult current CDC recommendations for HCP and specific state laws or recommendations.

Standard Precautions

Standard precautions are the practices by which healthcare personnel follow the same infection-control protocols for all clients regardless of infectious status or health history. Health history alone will not reliably identify all persons with HIV infection, HBV infection, or other blood-borne diseases. Some infected individuals are unaware of their status, and others may choose not to disclose their disease status on the health history. Certain precautions will prevent the transmission of these viruses when applied during client care. These precautions protect both the HCP and the patient from disease transmission.

Standard precautions are a synthesis of the major features of universal precautions and body substance isolation precautions and apply to the following:

Blood

Other bodily fluids, secretions, and excretions except sweat regardless of whether or not they contain visible blood

Nonintact skin

Mucous membranes

Therefore standard precautions apply to blood and all moist body substances.

Transmission-Based Precautions

Certain diseases require measures in addition to universal precautions, based on the route of transmission. Expanded or transmission-based precautions might be necessary to prevent potential spread of certain diseases (e.g., TB, influenza, and varicella) that are airborne or transmitted by droplet or contact (e.g., sneezing, coughing, and contact with skin). Persons acutely ill with these diseases do not usually seek routine dental care. Nonetheless, a general understanding of precautions for diseases transmitted by all routes is critical for the following reasons:

Some DHCP are hospital-based or work part-time in hospital settings.

Persons infected with these diseases might seek urgent treatment at outpatient dental offices.

DHCP might become infected with these diseases. Necessary transmission-based precautions might include client placement (isolation), adequate room ventilation, respiratory protection (N-95 masks) for DHCP, or postponement of nonemergency dental procedures.

The CDC has identified three categories of transmission-based precautions, as follows:

Contact precautions

Droplet precautions

Airborne precautions

Transmission-based precautions are used when the route of transmission are not completely interrupted using standard precautions alone. For some diseases that have multiple routes of transmission (e.g., severe acute respiratory syndrome [SARS]), more than one transmission-based precaution category may be used. Whether transmission-based precautions are used singly or in combination, universal precautions always apply as well.

In the case of clinically active TB, the level of protection afforded by standard precautions is not sufficient to prevent transmission. TB transmission is affected by a hierarchy of measures that include administrative controls, environmental controls, and personal respiratory protection. For clients known or suspected to have active TB, the CDC recommends the following:

Evaluate the client away from other clients and DHCP. When not being evaluated, the client should wear a surgical mask or cover mouth and nose when coughing or sneezing.

Defer elective dental treatment until the person is noninfectious.

Refer clients requiring urgent dental treatment to a previously identified facility with TB engineering controls and a respiratory protection program.

Health History (see Chapters 10 and 11)

The health history is an important tool for:

Understanding the client’s overall health

Assisting in making appropriate care and referral decisions

Identifying persons infected with diseases for which there may be a need for additional infection precautions (e.g., transmission-based precautions)

DHCP should be aware of signs and symptoms of infectious diseases and cognizant of the steps required to minimize risk of transmission. This is particularly important if a client has active TB, signs and symptoms of which may include coughing, chest pain, sweating, weight loss, and fever. Coughing, especially if persistent and if blood is present, is a key indicator of infection. A client with active TB or suspected of having active TB should be isolated from other clients, asked to wear a face mask, and educated to contact his or her physician of record for definitive medical diagnosis (e.g., presence or absence of TB).

The Mantoux test is the most common and accurate test for TB. The CDC recommends this test, which involves an intradermal injection of purified protein derivative (PPD) into the skin of the forearm. The area is observed for 48 to 72 hours after the injection for development of a wheal that is red, is raised, and measures at least 10 mm across. If it has been several years since the last time a person had a TB skin test, the physician may recommend repeating the test to rule out the potential for a false-negative result. For HIV-infected individuals, a 5-mm wheal is an indication of infection owing to the tendency of immunocompromised individuals to develop a lesser reaction. A positive skin test result is an indication of infection with the bacterium but is not an indication of active disease. In fact, the majority of individuals with a positive skin test result do not have active TB. About 10% of infected individuals will develop active TB in their lifetime. About 5% develop the active disease shortly after exposure, and 5% develop active disease later in life, usually owing to a compromised immune system.

Most people who experience a positive skin test result receive preventive chemotherapy for 6 months. The standard drug for prevention of active infection is isoniazid (INH). To treat an active infection (i.e., in a symptomatic person), physicians use INH in combination with other medications (e.g., rifampin, pyrazinamide). Rare cases of TB do not respond to traditional therapy. These cases, referred to as drug-resistant TB, are more likely to result in death of the infected individual.

Engineering Controls

Engineering controls are devices or equipment that reduce or eliminate a hazard (Figure 7-4). In the context of oral healthcare, these include the following:

Devices that contain or remove sharp items

Anesthetic syringes that contain shielding or encapsulation mechanisms

Anesthetic needles that contain shielding mechanisms

Disposable scalpels that do not require removal of a used blade

Scalpel handles with retractable blades

Figure 7-4 Examples of engineering controls. A, Sharps container with biohazard warning label. B, Dental safety syringe. C, Safety scalpel with retractable blade D, Disposable scalpel.

Consider the use of engineering controls when it is reasonable to believe that the control measure will reduce the potential for exposure to a client’s blood or body fluids. OSHA requires the use of sharps with engineered sharps injury protection when available and when found to provide superior protection compared with the standard devices. Examples include syringes with retractable needles or needle guards, scalpels with retractable blades or blade guards, and other devices that render the sharp safer through blunting, encapsulation, guarding, or destruction.

Work Practice Controls

Work practice controls reduce or eliminate a hazard by changing the way in which workers perform a task. Figure 7-5 shows improper positioning of fingers, placing the dental hygienist at risk. Proper client positioning that allows a 14- to 18-inch focal distance may reduce the hygienist’s exposure to contaminated droplets generated during certain procedures. Proper client positioning also increases visibility and access to the mouth, further decreasing the risk for accidental injury. Use of a high-speed evacuator while spraying a client’s mouth with air and water reduces the amount of droplet splash compared with the use of low-speed suction or no suction. Using an ultrasonic cleaner, washer, or disinfector to decontaminate used dental instruments before sterilization is another example of work practice controls. Use of automated instrument cleaning reduces the need for the DHCP to handle contaminated instruments.

Figure 7-5 Example of improper positioning of operator’s fingers, placing the dental hygienist at risk of a puncture wound.

Personal Protective Equipment

The term personal protective equipment (PPE) refers to garments, eye protection, airway protection, and other attire worn with the intent to protect the worker from blood and body fluid exposure. Work practice controls and engineering controls are the preferred method of protection. PPE is indicated when those controls will not prevent exposure to blood and body fluids. The PPE selected should protect the worker from exposure to the skin, clothing, eyes, mouth, and other mucous membranes during the normal course of his or her duties (see Figure 7-1).

Always base the selection of protective attire on the nature of the procedure and anticipated exposure risks. Procedures that generate spray or droplets of blood or saliva (e.g., scaling and root planing, air polishing) require a higher level of protection than procedures that do not produce body fluids (e.g., x-ray examinations). Do not base the selection of PPE on the infectious disease status of the client. The infection-control precautions for any given procedure should be the same for each client.

Eye and Face Protection

Appropriate eye protection includes goggles, glasses with solid side shields, or a face shield that protect the eyes from exposure to infectious, chemical, and physical hazards (Figure 7-6). The CDC recommends and OSHA regulates that protective eyewear meet the American National Standards Institute (ANSI) standards for spatter protection and impact protection. Healthcare workers who wear prescription eyeglasses should consult an eyecare professional to ensure that the style and materials of the eyewear meet ANSI standards for protective eyewear or should purchase ANSI-certified goggles or face shields that fit over the prescription eyewear.

Figure 7-6 Eye protection with side shields and surgical face mask.

When laser technologies are used, additional eye protection may be required. Every pair of safety goggles or safety glasses intended for use with laser beams must bear a label with the following information:

Laser wavelengths in use

Optical density of those wavelengths

Visible light transmission

Masks

A surgical mask protects the mucous membranes of the nose and mouth from exposure to spatter generated under a variety of dental procedures. Wear masks under the same circumstances that warrant the use of eye protection (Figure 7-7). Base the selection of masks on comfort, how well the periphery of the mask conforms to the contours of the face, and the level of filtration the mask provides. In general, a mask rated as surgical will have a filtration rating superior to that of masks rated as procedure masks.

Figure 7-7 Personal protective equipment: barrier gown, eyewear with side shields, and face mask.

Gloves

Gloves used for dental and dental hygiene procedures fall into three categories, as follows:

Medical examination gloves—nonsterile gloves that are available in a variety of sizes and materials, powdered and unpowdered, and either ambidextrous or right- or left-hand specific (Figure 7-8).

Sterile surgeon’s gloves (indicated for oral surgical procedures)—sterilize gloves individually packaged in sized pairs. To maintain sterility of gloves, do not open package until ready to use for surgical procedures.

Heavy-duty utility gloves—puncture-resistant gloves (Figure 7-9), used during cleaning and disinfection procedures to reduce risk of accidental puncture injury.

Figure 7-8 Examination gloves.

Figure 7-9 Heavy-duty utility gloves.

Hand Protection and Hand Hygiene

HCP are increasingly reporting allergic and nonallergic dermatitis of the hands. Many of these reactions are the result of contact with chemicals used in the manufacture of latex. However, a small percentage involve a potentially serious allergic reaction to the proteins found in natural rubber latex. It is important to seek the advice of a qualified healthcare professional (e.g., physician with specialty in dermatitis and allergies) when experiencing dermal problems related to the use of medical gloves.

Hand hygiene is the most important behavior in the prevention of disease transmission.

The preferred method for hand hygiene depends on the type of procedure, the degree of contamination, and the desired persistence of antimicrobial action on the skin (Table 7-3). Remove transient microbial flora and debris by cleaning the hands with detergent and water. The presence of colonized or resident flora on the hands requires the use of antiseptic agents. For routine dental procedures (e.g., screening, examination, and nonsurgical procedures), wash hands with either plain or antimicrobial soap and water. If the hands are not visibly soiled, an alcohol-based hand rub is adequate. Hand hygiene for surgical procedures (e.g., periodontal surgery, surgical extraction of teeth, biopsy) requires surgical hand antisepsis to eliminate transient flora and reduce resident flora.

TABLE 7-3 Types of Hand Hygiene

Antiseptic agents for surgical procedures should have a lasting antimicrobial effect on the hands for the duration of a procedure, to do the following:

Prevent introduction of organisms in the operative wound if gloves become punctured or torn

Prevent skin bacteria from multiplying under surgical gloves

However, frequent hand washing and the use of gloves may contribute to the development of nonallergic dermatitis, and it is important for dental healthcare workers to practice protective hand care as follows:

Thorough drying of hands after handwashing and before donning gloves

Use of powder-free gloves (or low amounts of powder)

Frequent use of appropriate lubricating hand lotions

Use of cool water when washing hands

Protecting hands from chapping and drying during cold weather

Protecting hands from cuts and scratches when performing household chores

Limit the Spread of Blood and Other Infectious Bodies

Cross-Contamination

Cross-contamination is the transfer of oral fluids and debris from a client to surfaces, equipment, materials, workers’ hands, or another person. Because saliva is invisible yet capable of containing high bacterial and viral particle loads, cross-contamination is particularly problematic in oral healthcare. Pathogenic organisms, potentially present in oral fluids, may survive on environmental surfaces for days, weeks, and even months if left untreated with a germicidal product.

Cross-contamination may be by direct or indirect means:

Direct cross-contamination occurs when a worker fails to change gloves between patients or fails to properly clean and sterilize instruments between uses. An example of direct cross-contamination is the use of a disposable dental product such as a saliva ejector on multiple clients.

Indirect cross-contamination occurs when handling a container, armamentaria, or equipment with contaminated gloves and failing to disinfect the items between clients.

Numerous strategies exist to prevent contamination. It is difficult or impossible to sterilize most items and surface areas in the oral care environment. Therefore the best way to manage environmental surfaces in the clinical environment is to clean and disinfect with an EPA-registered disinfectant or protect surfaces with fluid-impervious barriers (e.g., plastic covers). To be effective the disinfectant must come into direct contact with a precleaned surface.

The CDC designates environmental surfaces in the oral healthcare setting into two categories:

Housekeeping surfaces—areas that may be difficult or impossible to clean include switches, knobs, hoses, brackets, and many other items used in the delivery of care. Protect these surfaces by covering them with fluid-impervious barriers (see Figure 7-2). Always change barriers between clients.

Clinical contact surfaces—surfaces that become contaminated from spray or droplets of oral fluids or by touching with gloved hands during the procedure. These surfaces may be difficult to clean and can subsequently contaminate other instruments, devices, hands, or gloves. Disinfect or barrier-protect clinical contact surfaces including:

○ Touch areas on the dental chair

○ Touch areas on the operator chair

○ Dental unit

○ Dental light handle(s)

○ X-ray unit touch areas

○ Countertops that are contacted by contaminated items

○ Air and water syringe handle and tubing

○ Pencils, pens, face

○ Mirror for client education

○ Dental unit suction controls and disposable tip connection tubing

○ Saliva ejector holder and tubing

○ Bracket tables and bracket tray

○ Portable equipment (e.g., ultrasonic cleaner and scaler, airpolisher, curing light, vitalometer)

In the absence of barriers, clean and disinfect surfaces and equipment between clients with an EPA-registered hospital disinfectant (low-level disinfectant) or an EPA-registered hospital disinfectant with a tuberculocidal claim (intermediate-level disinfectant). Use intermediate-level disinfectant for surfaces with visible blood or other potentially infectious materials (OPIM) (Figures 7-10 and 7-11).

Figure 7-10 Spray disinfectant.

Figure 7-11 Disinfectant wipes.

General cleaning and disinfection are recommended for clinical contact surfaces, dental unit surfaces, and countertops at the end of daily work activities and are required if surfaces have become contaminated since their last cleaning. Keeping treatment areas free of unnecessary equipment and supplies facilitates daily cleaning.

Follow manufacturer directions for the handling, use, and storage of all disinfectant and cleaning products. Manufacturers of dental devices and equipment should provide information regarding material compatibility with liquid chemical germicides, precautions regarding immersion of devices for cleaning, and how to decontaminate the item if servicing is required. DHCP who perform environmental cleaning and disinfection should wear gloves and other PPE to prevent occupational exposure to infectious agents and hazardous chemicals. Chemical- and puncture-resistant utility gloves offer more protection than patient examination gloves when hazardous chemicals are used (Figure 7-12).

Figure 7-12 Use of PPE during disinfection of treatment area.

Sterilization and Sterility Assurance—Make Client Care Items Safe for Use

Client care items are either single-use disposable items or reusable items that require sterilization between uses. Sterilization is the destruction of all living organisms, including highly resistant bacterial spores. Properly performed cleaning and sterilization procedures offer the highest level of assurance that no pathogenic organisms remain on instruments and devices. The intent of instrument and equipment sterilization is not to establish a sterile care environment. Indeed, such an environment would be impossible to establish. Rather, the sterilization process ensures the destruction of all organisms transferred to an item during use on one client before reuse of the item on a subsequent client.

Instrument Classification

Dental instruments fall into three broad categories for determining the minimum level of management between clients (Table 7-4):

Critical instruments are instruments that penetrate soft tissue or bone. Critical instruments must be heat sterilized between each use or discarded if disposable. Examples of critical instruments and devices include periodontal probes, explorers, scaling and root planing instruments, and tip insert of an ultrasonic scaling unit.

Semicritical instruments are not intended to penetrate soft tissue or bone but contact oral fluids. Examples include mouth mirrors, ultrasonic scaling handpieces, impression trays, and oral photography retractors. These instruments should also be heat sterilized between each use. The use of high-level disinfectants is indicated for semicritical instruments that cannot be heat sterilized. These germicides are chemical disinfectants that provide sterilization under certain conditions. Chemical germicides are not as reliable as heat sterilization methods and raise worker safety concerns; therefore heat-stable or disposable alternatives are preferred.

Noncritical instruments and devices are those items that come into contact only with intact skin. Examples include an x-ray head, light handles, high- and low-volume evacuators, tubing for handpieces, instrument trays, countertops, and chair surfaces. Disinfect these items with an EPA-registered low- to intermediate-level disinfectant.

TABLE 7-4 Infection-Control Management of Instruments and Devices Based on Classification

Heat Methods of Sterilization

Heat-based sterilization methods are more time efficient and reliable than chemical germicides. It is important to determine the method of sterilization that provides a safe and effective outcome for the type of devices.

DHCP must use an FDA-approved sterilization device and follow the manufacturer’s instructions for cycle time, temperature, and other parameters involved in achieving sterilization. For satisfactory results, thoroughly clean instruments before placing into appropriate packaging and sterilizing. Three major types of heat sterilization are available:

Autoclave, the most common method of heat sterilization in the dental office, uses steam in a pressurized chamber to sterilize heat-stable instruments and devices. The user places distilled water into a chamber that dispenses the amount needed to provide steam for the process. Most autoclaves require several minutes to achieve the temperature necessary to begin the sterilization process. Additional time at the end of the sterilization cycle allows depressurization of the chamber. Two methods of air evacuation are available in autoclaves: prevacuum and gravity displacement.

○ A prevacuum (also known as class B sterilizer) usually consists of a sterilization chamber surrounded by a secondary jacket. When the sterilization cycle is initiated, the air is “pumped” out of the chamber, creating a vacuum into which steam is injected. Once the chamber reaches the desired temperature and pressure, the sterilization process begins. In many prevacuum sterilizers, the actual sterilization time is 4 to 5 minutes, followed by a 20-minute drying cycle. When using a prevacuum sterilizer, it is important to conduct an air removal test (often called a Bowie-Dick test) at the beginning of each day to ensure the process removes all air from the chamber (Figure 7-13). Pockets of air remaining after the prevacuum may result in incomplete sterilization of the contents.

○ Gravity displacement sterilization relies on gravity to evacuate the air from the sterilizer chamber. Pressurization of the autoclave relies on the effective removal of all air. As steam enters the gravity displacement sterilizer, gravity forces the air out through ventilation ports in the chamber. Gravity displacement is usually a longer process than prevacuum air displacement.

An unsaturated chemical vapor sterilizer uses a process similar to that of the autoclave; however, in place of steam, a chemical vapor enters the pressurized sterilization chamber. The use of chemical vapor instead of steam reduces the humidity of the sterilization process, reducing the risk of instrument rust and corrosion (primarily carbon steel instruments).

Dry-heat sterilization uses high heat for a specific amount of time to achieve sterile results. Temperatures often reach 350° F; therefore dry heat is likely to damage heat-sensitive items such as dental handpieces and some plastics.

Figure 7-13 Bowie-Dick air removal test. A, Test before use. B, Test indicating successful air removal.

Sterility Assurance

To ensure effectiveness of sterilization, several levels of sterility assurance are available, and a combination approach is best.

Chemical indicators allows the operator to determine the presence of certain necessary parameters such as heat or steam. These indicators often appear as arrows or color-change indicators on pouches used to package instruments during sterilization (Figure 7-14). They are also available as tape imbedded with stripes that change color or indicator strips. One should use chemical indicators with every packet of instruments as a signal to the user that the particular packet completed a heat sterilization process. The indicator is not an indication of effectiveness of the sterilization process itself because many factors may interfere with adequate sterilization.

Multiparameter indicators, also called integrators, are a higher level of sterilization assurance and indicate that more than one parameter required for sterilization was present (Figure 7-15). Different levels of integrators provide different levels of sterility assurance. Class V indicators are equivalent to a biologic indicator. The product manufacturer must establish the efficacy of the class V indicator with the Food and Drug Administration (FDA).

Biologic indicators (BIs), also called spore tests, are the highest level of verification (Figure 7-16). BIs use nonpathogenic spores that are especially resistant to the sterilization process embedded on a strip or in a solution that is placed in the sterilizer with a load of instruments. Incubation of the spore test confirms the destruction of the spores by the sterilization process, which indicates a successful sterilization process.

○ Geobacillus stearothermophilus is a standard organism for testing steam and chemical vapor sterilization.

○ Bacillus pumilus spores are the organisms most resistant to dry heat sterilization.

○ For monitoring a combination of sterilization methods, dual species biologic indicators (containing both types of spores) would be an appropriate choice.

Figure 7-14 Chemical indicator for steam autoclave.

Figure 7-15 Multiparameter integrator.

Figure 7-16 Biologic indicator (spore test).

Destruction of spores resistant to the specific sterilization methods indicates the elimination of all of the organisms of concern. Spore test at least weekly and with each implantable device to verify the proper functioning and operation of the sterilizer. Maintain records of spore testing and their results in the dental office. Many states require biologic monitoring (spore testing) and specify the length of time to maintain the test result records.

Exposure Prevention and Management

The risk of infection with a blood-borne disease after an occupational exposure to blood-borne pathogens in dental settings is low. However, every exposure to blood and body fluids carries some risk for transmission of blood-borne pathogens. Risk reduction strategies include the use of safer work practices, safer devices, PPE, proper policies and procedures, awareness of personal health status, attention to standard precautions, and a program of ongoing education. The majority of exposures are preventable. The CDC defines an occupational exposure as a percutaneous injury or contact of mucous membrane or nonintact skin with blood, saliva, tissue, or other body fluids that are potentially infectious. Exposure incidents may pose a risk of HBV, HCV, or HIV infection and are a matter of medical urgency.

Every dental facility must have a postexposure management program for occupational exposures. There should be a written program that identifies the specific steps to follow after an exposure incident and includes training and education as to the types of exposure that put dental healthcare practitioners at risk and procedures for prompt reporting and evaluation (including counseling, testing, and follow-up) according to the most current U.S. Public Health Service (USPHS) guidelines. These policies should be in compliance with the OSHA blood-borne pathogen standard and with any state or local laws or regulations.

Prevention and management of injury programs follow the public health doctrine of prevention:

Primary prevention strives to prevent the injury in the first place.

Secondary prevention strives to contain the injury.

Tertiary prevention strives to return to a functional state of no exposure and prevent similar injuries from occurring again.

Risk Reduction Protocols

Several risk reduction protocols center on the need to prevent percutaneous injuries:

Use of medical devices with engineered safety features designed to prevent injuries and/or use of safer techniques

○ Never recap needles by hand.

○ Never disengage needles from a reusable syringe.

○ Use disposable needle systems.

○ Dispose of needles and sharps in appropriate sharps disposal containers.

Avoidance of hand contact with sharps

○ Never wipe instruments on gauze in a hand or wrapped around a finger; use a single-hand technique instead, such as cotton rolls taped to an instrument tray or a commercial safe wipe device.

○ Announce instrument passes to warn others of sharps and exposure potential.

○ Create a neutral zone for sharps to avoid passing directly between healthcare workers.

○ Use appropriate cleanup procedures to minimize hand contact with sharps.

Work practice controls have some of the greatest impact on preventing blood-borne disease transmission. Given the types of exposures found in dental settings, over 90% are associated with needles or other sharp devices. The CDC determined that most occur outside the mouth and on the hands and fingers of the worker. Many of these are preventable with proper caution and the use of safer devices.

Postexposure Management

When an injury occurs, the goal is to contain the injury as soon as possible to reduce risk of transmission (secondary prevention). If an exposure occurs, offer the exposed worker immediate postexposure management in accordance with the most recent USPHS guidelines. It is critical to select a qualified healthcare provider (QHCP) trained to evaluate and treat infectious diseases, including HIV infection. In order for the QHCP to provide appropriate treatment and assess the need for follow-up, he or she must receive specific information regarding the exposure incident. This information includes the circumstances, devices, degree, and severity of exposure. If the source client consents, the QHCP will determine the source client’s infectious disease status through testing. Basic steps of postexposure management are as follows:

Step 1: Perform immediate first aid (no extraordinary measures). If an injury occurs, there are basic first aid measures to immediately apply such as washing an area of percutaneous exposure or flushing nose, mouth, eyes, or skin with clean water, saline, or sterile irrigants. There is no scientific evidence that the use of antiseptics for wound care or bleeding the wound will reduce the risk of transmission of a blood-borne pathogen. The exposed worker should not use caustic agents such as bleach.

Step 2: Report the incident to a designated individual. That individual will need to complete an incident report form (Figure 7-17). This includes the source patient’s name and the nature of the exposure. The completion of a report should not cause a delay or defer treatment.

Step 3: A designated individual should discuss the incident with the source patient.

Step 4: Initiate immediate referral to a QHCP capable of treating an exposed individual.

Step 5: Begin medical evaluation and follow-up in accordance with the most recent USPHS guidelines. Medical follow-up should include counseling and testing as indicated and determined by the infection potential of the exposure. Testing may be for HIV, HBV, or HCV; the QHCP may need to repeat testing at certain intervals. A rapid test for HIV is available in many settings. It would be prudent to ensure that the QHCP has access to this test. Results from a rapid test are available in less than a half hour rather than in days. Use of rapid testing results can assist in decision making for medical management.

Figure 7-17 Exposure reporting form.

Exposure Follow-Up Guidelines

HBV: Follow-up of occupational exposure to HBV depends on the HBsAg status of the source client and the vaccination and anti-HBs response of the exposed worker. If the exposed worker is unvaccinated for HBV, it is likely that the vaccination series will be initiated. A prevaccination titer test is not necessary. If the source individual has a history of HBV infection, administration of hepatitis B immune globulin will likely be part of the management protocol. Treatment should begin as soon as possible, preferably within 24 hours and in less than 1 week. If the exposed DHCP has been vaccinated and is a known responder, no action is necessary as the HBV vaccine has strong immunologic memory. However, if the immune status is unknown or the individual is a known nonresponder to the vaccine, other considerations must be taken.

HCV: There is neither preexposure vaccination nor postexposure prophylaxis (PEP) for occupational exposure to HCV. The most current recommendation for follow-up of occupational exposure to HCV is to test the source client for antibodies to hepatitis C virus (anti-HCV) and to test the exposed worker for anti-HCV and alanine aminotransferase (ALT) activity. Recommendations include repeated testing at 4 to 6 months. It is important to identify HCV infection early should transmission have occurred and to refer the exposed individual to a specialist. There are limited data to suggest that antiviral treatment initiated early in the course of infection may be beneficial.

HIV: Recommendations for HIV PEP are based on situations where there has been an occupational exposure to a source patient who either has or is considered likely to have HIV infection. If indicated, the worker should begin postexposure treatment as soon as possible (within 2 hours). The course of treatment usually involves a 4-week regimen of two or more antiretroviral drugs, depending on the nature of the exposure.

Postexposure management is an area of rapidly changing recommendations. As new antiretroviral agents become available, some are replacing drugs previously used. Therefore it is important to seek the advice and care of an appropriate provider who is familiar with the most current USPHS recommendations for testing and PEP. Counseling as to the potential side effects and reporting of illness are essential to the appropriate medical management of an occupational exposure to HIV.

The CDC recommends counseling as to the risks and benefits for the pregnant worker and extensive follow-up. Pregnancy may affect the selection of antiretrovirals because some of these drugs are contraindicated in a pregnant woman.

Risk of Exposure

Exposure risk varies with the amount of blood, the titer of virus in the patient, and the depth of the injury with the contaminate device or instrument. Immediate initiation of treatment is important, preferably within 2 hours. The goal is to prevent viral replication in the exposed worker, and there is biologic evidence that this is possible. Postexposure management with antiretroviral drugs may reduce risk of infection by about 80% but will not prevent all cases of infection. Postexposure management may fail owing to a resistant virus, an increased titer of virus, an increased dose of blood, or host factors.

Follow-up also involves counseling regarding signs and symptoms of infection, the importance of measures to not infect others, and the importance of seeking advice if illness occurs:

For HCV, it may be necessary to monitor liver function and have tests for HCV antibody. Often tests are repeated at 4 to 6 weeks.

For HIV, baseline testing is part of the standard protocol and repeat testing may be indicated at 6 weeks, 12 weeks, and 6 months, or even up to 1 year if co-infection with, for example, HCV is an issue. If the worker is taking antiretroviral drugs, the exposed person may need to have drug toxicity tests.

Risk of Infection

Most exposures do not lead to infection, and the risk of seroconversion may vary depending on the agent, the type of exposure, the amount of blood involved, and the amount of circulating virus in the source client. When assessing an occupational exposure and determining the management and follow-up, a QHCP will review the following:

Type of exposure (percutaneous, mucous membrane, nonintact skin or bite) exposure

Type and amount of fluid (blood versus fluids containing blood)

Infectious status of the source such as presence of HBsAg, presence of HCV antibody, and/or presence of HIV antibody

Susceptibility of exposed person with consideration to the HBV vaccine response status and the HBV, HCV, and/or HIV status

For HBV the risk of infection ranges from 6% to 30% in persons not protected by vaccination or previous infection. Source individuals who are hepatitis e-antigen positive are potentially more infectious and more likely to transmit diseases. The best protection is vaccination against HBV.

For HCV the risk is about 1.8% on average for percutaneous exposures. There are no exact estimates of the number of healthcare workers occupationally infected with HCV, but the risk to a healthcare worker is no higher than the average community risk.

For HIV, average risk after a percutaneous exposure is about 0.3%. The risk after exposure to eyes, nose, or mouth is about 0.1%, and the risk to skin is estimated to be less than that unless the skin is damaged or compromised, in which case the risk would be higher.

In tertiary prevention the healthcare professional learns from the exposure incident, restores those exposed to a state of no infection, and takes all steps to reduce future exposure risk by:

Evaluating the circumstances of the exposure

Reviewing policies, procedures, products, devices, and practices; perhaps modifying policies or procedures and/or selecting safer devices

Discussing appropriate modifications

Determining how to communicate these to others

Maximum effort should be aimed at injury prevention because preventing an exposure in the first place is far better than dealing with the consequences of an exposure. These include medical management and follow-up as prescribed. Preventive strategies include the routine use of barriers when anticipating contact with blood or OPIM, adherence to hand washing, and the careful handling and disposal of sharps during and after use. Therefore avoiding occupational exposure involves the use of engineering controls, work practice controls, and PPE.

CLIENT EDUCATION TIPS

Explain infection-control protocols used in the delivery of dental hygiene care and their underlying rationale.

Explain that infection control is done to protect and not to keep an unnatural distance between client and clinician.

Discuss postexposure protocols at the initial appointment in case of an exposure.

LEGAL, ETHICAL, AND SAFETY ISSUES

Using evidence-based infection-control protocols is both an ethical and a legal requirement for dental hygienists.

Evidence-based standard precautions are a standard of care. Healthcare personnel who fail to render services using current standards of care place themselves at risk for both civil and criminal violations.

The reasonably prudent dental hygiene practitioner must stay current with regard to changing infection-control concepts, protocols, and governmental guidelines; this is a matter of state law or regulation in some jurisdictions.

It is unethical and illegal to refuse treatment to a client of record because that person has an infectious disease or to refuse to treat a person based on the presence of an infectious disease.

Adhere to state and federal laws that protect against discrimination based on race, religion, gender, sexual orientation, or disability, including infectious disease.

KEY CONCEPTS

Sterilization and surface disinfection can be achieved by physical or chemical means based on the equipment, type of procedure, and level of exposure risk.

Hand washing is the most effective strategy in the prevention of infection and disease transmission.

The Centers for Disease Control and Prevention recommendations for standard precautions indicate that healthcare personnel use personal protective equipment when exposure to body fluids is likely.

The basic tenet of standard precautions is that all clients should be viewed as potentially infected.

Healthcare practitioners who adhere to infection prevention and control strategies reduce the risk of infection for themselves, their families, and their clients.

CRITICAL THINKING EXERCISES

You have been hired by one of the most reputable dental practices in the community. On the second day of employment, while treating your client, you accidentally insert a used hypodermic needle percutaneously into your thumb after administering a local anesthetic agent. Because your client is a high-profile state legislator and you do not want to appear incompetent to your new employer or the client, you say nothing about the exposure incident. After 3 days of thinking about the situation, you report the incident to the office manager. Use the principles of postexposure management to determine the following:

1. What should the office manager do to protect the health and safety of the new dental hygienist?

2. What errors in judgment were made by the dental hygienist?

3. What steps of the postexposure management protocol should have been taken by the dental hygienist?

4. What tertiary preventive strategies need to be initiated by the office manager for the practice to ensure that a similar exposure incident does not occur?