- Email: [email protected]
Correlates of infection control practices in dentistry
Correlates of infection control practices in dentistry Robyn R. M. Gershon, MHS, DrPHa Christine Karkashian, MAa David Vlahov, RN, PhDb Martha Grimes, RN, CICc Elizabeth Spannhake, MPH, DDSd Baltimore, Silver Spring, and Westminster, Maryland
Background: Studies conducted in the first decade of the AIDS epidemic indicated that, in general, dentists had suboptimal levels of compliance with standard infection control practices, including work practices designed to reduce exposure to bloodborne pathogens. This study was designed to assess current rates of compliance with these practices in a population of Maryland dentists and to identify correlates of safe work practices. Methods: We surveyed 648 Maryland dentists using a confidential, self-administered questionnaire. Results: Three hundred and ninety-two questionnaires were returned (60% response rate). We found that infection control practices were variable as reported by responding dentists. In addition, several potentially modifiable factors were found to be significantly correlated with these practices, including (1) attitudes toward patients infected with HIV and (2) safety program management within the practice. Conclusion: These data are encouraging in that recommended infection control practices are being adopted, at least among a sample of Maryland dentists. Strategies for further improvement are identified. (AJIC Am J Infect Control 1998;26:29-34)
As early as 1976, the American Dental Association published infection control (IC) guidelines, and periodically these have been updated.1-4 Shortly after the start of the AIDS epidemic, specific work practice guidelines were also developed to help minimize the risk of bloodborne pathogen exposure within the dental setting. For example, in 1985 the Centers for Disease Control (CDC) published specific recommendations for dentists.5 In 1991 the Occupational Safety and Health Administration of the U.S. Department of Labor published the Bloodborne Pathogens Standard that applied to the dental workplace.6 Taken together, these and other related documents detail safe work practices for dentists and dental ancillary staff, including the cleaning and sterilization of instruments, the effective use of From the Departments of Environmental Health Sciencea and Epidemiology,b School of Public Health, The Johns Hopkins University, Baltimore; Department of Infection Control,c Holy Cross Hospital, Silver Spring; and private practice,d Westminster. Supported by the National Institute of Occupational Safety and Health and the Educational Resource Center, Inc. Reprint requests: Dr. Robyn R. M. Gershon, The Johns Hopkins University, School of Public Health, Department of Environmental Health Science, 615 N. Wolfe St., Room 1013, Baltimore, MD 21205. Copyright © 1998 by the Association for Professionals in Infection control and Epidemiology, Inc. 0196-6553/98/$5.00 + 0
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barrier protection, the safe handling and disposal of contaminated sharps, the training of personnel, and medical surveillance guidelines, including hepatitis B vaccination practices.7-11 In 1990 public concern regarding IC practices within the dental setting increased after CDC reported on the possible nosocomial transmission of HIV within the dental setting.12 This concern may have been heightened by early reports documenting suboptimal compliance with recommended IC practices, including compliance with universal precautions (UP).13-16 This study was designed to go beyond simply assessing levels of compliance with IC practices among dentists. Rather we were interested in learning which factors, if any, might serve as motivators toward the adoption of IC practices. This study complements similar studies we have conducted on other health care populations in which we have similarly tried to identify barriers to safe work practices so as to best address them. On the basis of our earlier findings we hypothesized that barriers to IC practices would fall into one of three major domains or constructs. These were: (1) individual factors (gender, age, number of years of practice, number of hours worked per week, type of dental practice, level of knowledge related to HIV transmission and UP practices, etc.), (2) psychosocial factors (perception of risk, fear of contagion, attitudes toward HIV/AIDS patients, 29
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knowledge and perception regarding efficacy of prevention, conflict of interest between providing care for patients and taking precautions, level of work stress, and risk-taking personality profile), and (3) organizational/management factors (safety management within the practice, general attitudes toward safety practices, amount of previous training in safe work practices, availability of personal protective equipment, environmental conditions in the office, and interpersonal conflict at work). The outcome measure, compliance with IC practices, was determined by means of a scale composed of 12 different items. Dentists were also asked questions related to occupational exposure to blood and other body fluids. METHODS Subjects
A list of Maryland dentists was obtained from the Maryland State Department of Health, Board of Dental Examiners. All procedures were approved by The Johns Hopkins University School of Public Health, Committee on Human Volunteers. The questionnaire, along with a consent form and disclosure cover letter, was mailed to every fifth dentist on the list, resulting in a final sample of 648 practicing dentists. After extensive follow-up procedures (e.g., three follow-up reminders), a total of 392 usable questionnaires were returned (60% response rate). Statistical analysis Questionnaire
A 12-page, 340-item questionnaire was developed to answer the research questions. Most constructs were measured using well-defined scales that had previously been psychometrically analyzed and validated. The questionnaire was extensively pilot-tested, and all new scales were factor analyzed. All scales were evaluated for internal consistency using Cronbach’s alpha coefficient and the correlation between items within each scale was adequate, with alpha values ranging from 0.74 to 0.90 for all scales, indicating high reliability.17 Most questionnaire items had a 4- or 5-point Likert-type response (strongly agree, agree, disagree, strongly disagree).18 Responses to some items were reverse-scored so that items in each scale could be scored in the same direction. Samples of the questionnaire and coding information may be obtained by contacting the corresponding author. Two-variable, c2 analyses were performed to assess variables correlated with
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compliance with UP. Variables significant on univariate analyses were entered into a hierarchical, stepwise logistic regression model. Individual factors
Sociodemographics. The respondents were predominantly men (85%), with a mean age of 46 years (± 11 years). Most of the respondents (72%) were in private practice, 23% were in group practice, and the remaining 5% held teaching or other positions. The mean length of tenure in the dental field was 19.3 years. Most respondents (90%) worked between 40 and 50 hours per week. Another 9% reported working at least 2 hours per week at another job (range, 2 to 40 hours). The respondent characteristics are representative of Maryland dentists and are similar to other published demographic profiles of dentists.13-16,19,20 The dentists reported an average of one HIVinfected person seen at their office each week (range, 0 to 30) out of a mean of 103 patients (range, 4 to 500 patients per week). Knowledge. Knowledge scores, as determined using a well-defined AIDS knowledge scale, were noted to be generally very high: 96% of respondents were very knowledgeable about UP practices and 82% scored high on an HIV/AIDS general knowledge set of questions.21 However, only 35% of dentists scored high on a set of questions dealing with alternate modes of transmission (e.g., “HIV may be transmitted through mosquitoes”).21 Some deficiencies were also noted with respect to knowledge regarding transmission within the dental setting. For example, 44% of respondents thought that HIV could be transmitted through direct contact (intact skin) with an infected patient’s saliva, and 67% thought that HIV could be transmitted through a splash to the dentist’s eyes or mouth, both of these routes are extremely unlikely. Most dentists (79%), however, thought it was possible for HIV to be transmitted from visibly contaminated dental equipment and materials. And dentists were familiar with the risks associated with hepatitis B virus; only a small number of the dentists, 4%, did not think hepatitis B virus could be transmitted through contaminated instruments. Psychosocial variables
Risk perception and fear. Most dentists did not perceive themselves to be at risk of infection with bloodborne pathogens; only 15% thought that their risk was high. However, 28% reported high levels of fear of contagion. Ten percent of dentists said that they would not treat a patient known to have HIV, and 11% said they would not treat a
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patient known to have hepatitis B virus infection. Eighteen percent of respondents agreed with the statement “the medical profession is not telling everything it knows about AIDS.” Attitudes toward patients with HIV/AIDS. Most dentists (69%) scored high on a well-characterized HIV/AIDS attitudes scale, indicating that they were generally tolerant and accepting of patients infected with HIV or diagnosed with AIDS, although 43% said they would prefer to refer HIV-infected patients elsewhere.22 Fifty-six percent of respondents believed health care workers should have the right to refuse to treat HIV-infected patients. Efficacy of prevention. A very high percentage of dentists (98%) believed that adopting IC practices would protect them from exposure. For example, 98% of dentists “agreed” or “strongly agreed” with the statements “I can reduce my risk of occupational HIV infection by complying with UP” and “If UP are followed with every patient, my risk of HIV/AIDS will be very low.” Conflict of interest. We have previously shown that compliance with self-protective behaviors is especially poor if health care workers believe they cannot provide optimal patient care and still protect themselves from exposure to bloodborne pathogens.23 We refer to this construct as “conflict of interest.” The overall mean score on the “conflict of interest” scale (four items) for all dentists was 0.83 ± 0.60 (range, 0 to 4), indicating that few dentists perceived a conflict between providing care to patients and taking care of themselves. For example, only 14% believed that “the patients’ needs come first.” Work stress. Previously, we have shown an inverse correlation between high levels of work stress and the adoption of safe work practices.23 Work stress was measured by using an 18-item scale adapted from Revicki’s Work-Related Stress Inventory (WRSI).24 The mean score for this scale was 1.97 ± 0.47 (range, 1 to 4), indicating a moderate level of work stress. Examples of items included: “I occasionally hide in my office from others to shut them out,” and “It seems like I cannot get the recognition I deserve.” Sixty-six percent of dentists reported being “very satisfied” with their work. Organizational/management factors
Examples of relevant organizational-level factors that we previously found significantly associated with the adoption of safe work practices include the attitude toward safety management in the practice, the provision of safety training, the availability and accessibility of personal protec-
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tive equipment, general environmental conditions, and interpersonal relations in the workplace, as noted later in this article.23 Attitudes toward safety management. Respondents generally rated the overall safety management of their practices as good. For example, 62% agreed with the following statements: “The protection of workers from occupational exposure to HIV is a high priority for me,” “In my office, all reasonable steps are taken to minimize hazardous job tasks and procedures,” and “Where I work, unsafe work practices are corrected by me.” Training and personal protective equipment. Many dentists reported having received extensive training on IC practices in the previous 12 months. For instance, 57% reported receiving 6 or more hours of IC training, 23% reported 3 to 5 hours, 16% reported 1 to 2 hours, and only 4% reported that they had not received any IC training in the previous 12 months. Most of their training was in the form of written materials, although attendance at training films was also cited as a resource, as well as attendance at conferences. It should be noted that Maryland dentists are required to obtain continuing education credits on an ongoing basis. The provision of personal protection equipment was a high priority for dentists, with more than 98% reporting offering all the necessary equipment to their employees. Environmental conditions. Because we previously found an association between general working conditions and the adoption of safe work practices, we included several questions regarding the environmental conditions in the practice.23 Temperature extremes in the office were the most common complaint of the dentists, with 31% reporting that they were “always” or “often” uncomfortable because of temperature extremes at work. Other environmental conditions that were found to be a source of discomfort included loud noises (16%), poor lighting (13%), and unpleasant odors (11%). Injuries/exposures. Dentists frequently reported exposure to patients’ blood and saliva. For example, 28% of respondents reported either parenteral or mucocutaneous exposure to patients’ saliva or blood in the previous 6 months. Of these, 4% involved HIVcontaminated blood. Seven percent (n = 27) of the dentists reported one or more contaminated needlesticks in the previous 6 months, and, of these, only 3% received any treatment or follow-up for their exposure. Twelve percent of the dentists reported getting splashed in the previous 6 months and 16% reported one or more sharps-related injury.
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Table 1. Proportion of dentists who reported compliance with individual IC practices (n = 392)
Practice
1. Disposal of sharps into sharps containers 2. Refrain from recapping contaminated needles (using the two-handed method) 3. Washing hands after removal of gloves 4. Wearing outer protective garments 5. Wearing disposal gloves 6. Use of protective eye shields 7. Use of face masks 8. Disposal of contaminated materials 9. Cleaning of patient-related spills promptly 10. Refraining from eating while treating patients 11. Using extreme caution with sharp instruments 12. Treating saliva-contaminated materials (paper cups, etc.) as infectious
Percent responding “always”
87.9 37.0 59.1 37.2 97.6 80.8 79.7 82.1 84.0 80.9 90.0 64.7
IC practices
Thirty-six percent of the dentists reported that they “always” complied with each of the 12 IC items. Dentists were most compliant with proper sharps disposal practices (88%) and the wearing of disposable gloves (98%) and least compliant with refraining from recapping contaminated needles; 63% reported that they “always” recapped needles using the improper two-handed method. Other practices that had poor compliance included wearing protective clothing (37%), washing hands after the removal of gloves (59%), and wearing protective face masks (80%). Specific responses for each individual item on the scale are shown in Table 1. Most dentists reported they were personally responsible for the IC programs in their office, which many respondents characterized as quite extensive; for example, 90% had an office safety program, including written IC policies. Yet there were some discrepancies because although 97% of the dentists stated that strict compliance with IC practices was expected by their staff, only 79% of the dentists said that they always personally complied with IC practices. And although 96% of the respondents stated that disinfection and sterilization procedures were strictly adhered to, only 76% reported that they consistently sterilized all their handpieces. Almost all dentists (99%) believed that they set a good example regarding IC for the rest of their staff. Most (82%) of the dentists disposed of their regulated medical waste by shipping it to an off-site
incinerator, but a small fraction (8%) admitted to putting it into the regular trash. Finally, more than 90% of dentists reported making significant changes in their IC practices in the preceding 12 months, and 60% were currently satisfied with their IC program. Medical surveillance practices
A high percentage of dentists (97%) offered the hepatitis B vaccine to their staff, and a large percentage of dentists (84%) had personally received the vaccine. When asked whether they would take zidovudine as a prophylactic treatment after an HIV-contaminated needlestick, 37% said yes; however, only 7% thought that it would be effective in preventing infection. Univariate analysis—correlates of IC practices
Significant relationships were found between high levels of compliance with IC practices and the following factors: (1) tolerant attitudes toward HIV/AIDS patients (p < 0.05), (2) high levels of belief that IC practices were effective in exposure prevention (p < 0.05), (3) high scores on a test of general knowledge on HIV/AIDS (p < 0.05), and (4) positive attitudes of the dentist toward safety management within the dental practice (p < 0.001). Importantly, the history of exposure was also significantly associated with compliance (p < 0.05). Multivariate models
When the significant univariate items were entered into a hierarchical stepwise model, only two variables were determined to be significantly associated with compliance in multivariate analysis: (1) tolerant attitudes toward patients with HIV/AIDS (odds ratio [OR] = 1.72, CI95 = 1.05, 2.79) and (2) positive attitudes toward safety in the practice (OR = 2.72, CI95 = 1.70, 4.36). Individual factors, such as sociodemographic information and other organizational and psychosocial variables assessed in this sample of dentists were not found to be significantly associated with IC practices at the multivariate level. DISCUSSION
Improvements in dental IC practices have been steadily made since the start of the HIV epidemic. For example, in a 1986 nationwide study conducted by the American Dental Association it was reported that 80% of the respondents wore protective eyewear, 20% wore disposable gloves, 20% wore face masks, and 12% wore protective clothing when providing care for all patients.20 Gerbert19 reported in a 1987 study that 80% of respondents (n = 297) consistently wore gloves, 70% wore masks, 33% wore protective garments,
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39% sterilized handpieces, and 80% used disinfectants appropriately. In 1990 a report by Hazelkorn25 indicated that 87% of respondents reported that they wore gloves, and 89% reported that they wore masks. In 1991 the American Dental Association reported increases in all the following IC practices compared with their 1986 findings, rises on glove use (90%), the use of masks (60%), and the use of protective clothing (64%).26 In 1992 a report by Woo et al.27 indicated that 27% of the dentists in their study sterilized handpieces. Finally, in a study conducted by Feldman and Bramson in 1994,28 it was reported that in 92% of the U.S. dental practices they surveyed, consistent sterilization of handpieces was performed. In our study, glove use was reported to be 98%; 37% reported frequently wearing protective garments, 80% wore face masks, 84% used disinfectants, and 76% sterilized handpieces. Recapping has been a noted problem in the past for dentists because of the nature of the injections that they give (e.g., anesthetics), which are often given multiple times throughout a procedure, and we noted similarly high rates of recapping. Overtime, improvements have been made in the acceptance of the hepatitis B vaccine in the dental community. The Dental Division of the Indiana State Board of Health, which has been surveying Indiana dentists since 1985, found that vaccination was reported by 37% of dentists in 1985, but by 1988, 67% (n = 1200) had been vaccinated.29 In our sample, 84% of respondents reported that they had received the vaccine. Our finding that the two most significant correlations with compliance were tolerant attitudes toward patients with HIV/AIDS and strong safety management programs is important because it provides direction for intervention strategies. In an earlier study we identified several important determinants of tolerant attitudes toward patients with HIV/AIDS; these were (1) personally knowing someone who was infected with HIV or who had been diagnosed with AIDS, (2) high scores on tests that measured general HIV/AIDS knowledge and alternate modes of transmission (casual contact), (3) low levels of fear of contagion, and (4) accurate perceptions of risk of occupational infection.30 Many of these determinants can be readily addressed through appropriate and targeted educational programs. Dentists wishing to improve the overall safety management of their practice should conduct periodic safety management audits to assess their current status and then
make adjustments accordingly (contact corresponding author for information on resources). Finally, our finding that overall compliance with IC practices was found to be associated with exposure is consistent with other health care workers who also showed this relationship.31,32 Although caution must be exercised in comparing studies conducted at different times, with different dental populations, and with different instruments, our data confirm a trend in improvements in IC practices that continues to be made within the dental community. These findings indicate that although room for improvement still exists, important advances in this area appear to have been made. Although our findings are encouraging, they must be viewed with some reservations. First, selfreports, even confidential ones, may seriously overestimate socially desirable responses. Second, despite extensive follow-up procedures, only 60% of our sample responded to the questionnaire, thus raising the issue of self-selection bias; dentists who responded to the questionnaire may have been more concerned about IC issues than nonrespondents and thus more likely to be more conscientious about IC. However, our sample’s demographics were similar to that of Maryland dentists as a whole, perhaps indicating that the respondents were representative of Maryland dentists. However, Maryland dentists may not be representative of dentists as a whole (self-selection bias). Despite these caveats, we remain optimistic and confident that important improvements in IC practices continue to be made in the dental community. It will be important to reevaluate this issue to determine whether improvements continue. We thank Sylvia Cohn for statistical assistance, Meghan Dunleavy for research assistance, and Patricia Flanagan for editorial assistance.
References 1. American Dental Association Council on Dental Therapeutics. Type B (serum) hepatitis and dental practice. J Am Dent Assoc 1976;92:153-9. 2. American Dental Association Council on Dental Materials and Devices and Council on Dental Therapeutics. Infection control in the dental office. J Am Dent Assoc 1978;97:673-7. 3. American Dental Association Council on Dental Materials, Instruments and Equipment and Council on Dental Practice, and Council on Dental Therapeutics. Infection control recommendations for the dental office and dental laboratory. J Am Dent Assoc 1988;116:241-8. 4. American Dental Association Council on Dental Therapeutics and Council on Prosthetic Services and Dental Laboratory Relations. Guidelines for infection control in the dental office and the commercial dental laboratory. J Am Dent Assoc 1985;110:969-72.
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34 Gershon et al. 5. Centers for Disease Control. Recommendation for preventing transmission of infection with human T-lymphotropic virus type III/lymphadenopathy-associated virus in the workplace. MMWR Morb Mortal Wkly Rep 1985;34:681-6,691-5. 6. Occupational Safety and Health Administration. Final standard for occupational exposure to blood borne pathogens: December 6, 1991. 29 CFR 1910.1030. 7. Centers for Disease Control. Recommended infection control practices for dentistry. MMWR Morb Mortal Wkly Rep 1986;15:237-42. 8. Centers for Disease Control. Recommendations for prevention of HIV transmission in health care settings. MMWR Morb Mortal Wkly Rep 1987;36(Suppl 2s):1s-16s. 9. Centers for Disease Control. Update: universal precautions for prevention of transmission of human immunodeficiency virus, hepatitis B virus, and other bloodborne pathogens in health care settings. MMWR Morb Mortal Wkly Rep 1988;37:377-82,387-8. 10. Centers for Disease Control. Guidelines for prevention of transmission of human immunodeficiency virus and hepatitis B virus to health care and public safety workers. DHHS (NIOSH) Pub. No. 1-46. Atlanta, GA, 1989. 11. Centers for Disease Control. Recommended infection control practices for dentistry. MMWR Morb Mortal Wkly Rep 1993;42:1-12. 12. Centers for Disease Control. Possible transmission of human immunodeficiency virus to a patient during an invasive dental procedure. MMWR Morb Mortal Wkly Rep 1990;39:489-93. 13. Hazelkorn HM. Do dentists have sufficient information about their patients to control infection? J Dent Educ 1990;54:149-52. 14. Dorsey M, Overman P, Hayden WJ, et al. Relationships among and demographic predictors of dentists’ self-reported adherence to national guidelines. Soc Sci Med 1991;32:1263-8. 15. Hardie J. The attitudes and concerns of Canadian dental health care workers toward infection control and the treatment of AIDS patients. J Can Dent Assoc 1992;58:131-8. 16. Passannante MR, French J, Louria DB. How much do health care providers know about AIDS? Am J Prev Med 1993;9:6-14. 17. Cronbach LJ. Coefficient alpha and the internal structure of tests. Psychometrika 1951;16:297-334.
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18. Likert R. A technique for the measurement of attitudes. Arch Psychol 1932;140:1-55. 19. Gerbert B. AIDS and infection control in dental practice: dentist’s attitudes, knowledge and behavior. J Am Dent Assoc 1987;114:311-24. 20. Verrusio AC, Neidle EA, Nash KD, et al. The dentist and infectious diseases: a national survey of attitudes and behavior. J Am Dent Assoc 1989;118:553-62. 21. National Center for Health Statistics. AIDS knowledge and attitudes. Vital Health Stat 1988;161(3):1-12. 22. Shrum JC, Turner NH, Bruce KE. Development of an instrument to measure attitudes toward acquired immune deficiency syndrome. AIDS Educ Prev 1989;1:222-30. 23. Gershon RRM, Vlahov D, Felknor S, et al. Compliance with universal precautions among health care workers at three regional hospitals. Am J Infect Control 1995;23:225-36. 24. Revicki DA, May HJ, Whitley TW. The health professional stress inventory: development and validation. Greenville (NC): East Carolina University; 1988. 25. Hazelkorn HM. Do dentists have sufficient information about their patients to control infection? J Dent Educ 1990;54:149-52. 26. Nash KD. How infection control procedures are affecting dental practice today. J Am Dent Assoc 1992;123:67-73. 27. Woo J, Anderson R, Maguire B, et al. Compliance with infection control procedures among California dentists. Am J Orthod Dentofac Orthop 1992;102:68-75. 28. Feldman MC, Bramson JB. What is the cost of compliance? J Am Dent Assoc 1994;125:682-6. 29. Mollenkopf JP, Smith CE. Indiana dentists’ acceptance of universal precautions. J Ind Dent Assoc 1990;69:29-33. 30. Gershon RRM, Curbow B, Kelen G, et al. Correlates of HIV/AIDS-related attitudes among hospital workers. Am J Infect Control 1994;22:293-9. 31. Wong WS, Stotka JL, Chinchilli VM, et al. Are universal precautions effective in reducing the number of occupational exposures among health care workers? A prospective study of physicians on a medical service. JAMA 1991;265:1123-8. 32. Beekmann SE, Vlahov D, Koziol D, et al. Temporal association between implementation of universal precautions and a sustained, progressive decrease in percutaneous exposures to blood. Clin Infect Dis 1994;18:562-9.
Background: Studies conducted in the first decade of the AIDS epidemic indicated that, in general, dentists had suboptimal levels of compliance with standard infection control practices, including work practices designed to reduce exposure to bloodborne pathogens. This study was designed to assess current rates of compliance with these practices in a population of Maryland dentists and to identify correlates of safe work practices. Methods: We surveyed 648 Maryland dentists using a confidential, self-administered questionnaire. Results: Three hundred and ninety-two questionnaires were returned (60% response rate). We found that infection control practices were variable as reported by responding dentists. In addition, several potentially modifiable factors were found to be significantly correlated with these practices, including (1) attitudes toward patients infected with HIV and (2) safety program management within the practice. Conclusion: These data are encouraging in that recommended infection control practices are being adopted, at least among a sample of Maryland dentists. Strategies for further improvement are identified. (AJIC Am J Infect Control 1998;26:29-34)
As early as 1976, the American Dental Association published infection control (IC) guidelines, and periodically these have been updated.1-4 Shortly after the start of the AIDS epidemic, specific work practice guidelines were also developed to help minimize the risk of bloodborne pathogen exposure within the dental setting. For example, in 1985 the Centers for Disease Control (CDC) published specific recommendations for dentists.5 In 1991 the Occupational Safety and Health Administration of the U.S. Department of Labor published the Bloodborne Pathogens Standard that applied to the dental workplace.6 Taken together, these and other related documents detail safe work practices for dentists and dental ancillary staff, including the cleaning and sterilization of instruments, the effective use of From the Departments of Environmental Health Sciencea and Epidemiology,b School of Public Health, The Johns Hopkins University, Baltimore; Department of Infection Control,c Holy Cross Hospital, Silver Spring; and private practice,d Westminster. Supported by the National Institute of Occupational Safety and Health and the Educational Resource Center, Inc. Reprint requests: Dr. Robyn R. M. Gershon, The Johns Hopkins University, School of Public Health, Department of Environmental Health Science, 615 N. Wolfe St., Room 1013, Baltimore, MD 21205. Copyright © 1998 by the Association for Professionals in Infection control and Epidemiology, Inc. 0196-6553/98/$5.00 + 0
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barrier protection, the safe handling and disposal of contaminated sharps, the training of personnel, and medical surveillance guidelines, including hepatitis B vaccination practices.7-11 In 1990 public concern regarding IC practices within the dental setting increased after CDC reported on the possible nosocomial transmission of HIV within the dental setting.12 This concern may have been heightened by early reports documenting suboptimal compliance with recommended IC practices, including compliance with universal precautions (UP).13-16 This study was designed to go beyond simply assessing levels of compliance with IC practices among dentists. Rather we were interested in learning which factors, if any, might serve as motivators toward the adoption of IC practices. This study complements similar studies we have conducted on other health care populations in which we have similarly tried to identify barriers to safe work practices so as to best address them. On the basis of our earlier findings we hypothesized that barriers to IC practices would fall into one of three major domains or constructs. These were: (1) individual factors (gender, age, number of years of practice, number of hours worked per week, type of dental practice, level of knowledge related to HIV transmission and UP practices, etc.), (2) psychosocial factors (perception of risk, fear of contagion, attitudes toward HIV/AIDS patients, 29
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knowledge and perception regarding efficacy of prevention, conflict of interest between providing care for patients and taking precautions, level of work stress, and risk-taking personality profile), and (3) organizational/management factors (safety management within the practice, general attitudes toward safety practices, amount of previous training in safe work practices, availability of personal protective equipment, environmental conditions in the office, and interpersonal conflict at work). The outcome measure, compliance with IC practices, was determined by means of a scale composed of 12 different items. Dentists were also asked questions related to occupational exposure to blood and other body fluids. METHODS Subjects
A list of Maryland dentists was obtained from the Maryland State Department of Health, Board of Dental Examiners. All procedures were approved by The Johns Hopkins University School of Public Health, Committee on Human Volunteers. The questionnaire, along with a consent form and disclosure cover letter, was mailed to every fifth dentist on the list, resulting in a final sample of 648 practicing dentists. After extensive follow-up procedures (e.g., three follow-up reminders), a total of 392 usable questionnaires were returned (60% response rate). Statistical analysis Questionnaire
A 12-page, 340-item questionnaire was developed to answer the research questions. Most constructs were measured using well-defined scales that had previously been psychometrically analyzed and validated. The questionnaire was extensively pilot-tested, and all new scales were factor analyzed. All scales were evaluated for internal consistency using Cronbach’s alpha coefficient and the correlation between items within each scale was adequate, with alpha values ranging from 0.74 to 0.90 for all scales, indicating high reliability.17 Most questionnaire items had a 4- or 5-point Likert-type response (strongly agree, agree, disagree, strongly disagree).18 Responses to some items were reverse-scored so that items in each scale could be scored in the same direction. Samples of the questionnaire and coding information may be obtained by contacting the corresponding author. Two-variable, c2 analyses were performed to assess variables correlated with
February 1998
compliance with UP. Variables significant on univariate analyses were entered into a hierarchical, stepwise logistic regression model. Individual factors
Sociodemographics. The respondents were predominantly men (85%), with a mean age of 46 years (± 11 years). Most of the respondents (72%) were in private practice, 23% were in group practice, and the remaining 5% held teaching or other positions. The mean length of tenure in the dental field was 19.3 years. Most respondents (90%) worked between 40 and 50 hours per week. Another 9% reported working at least 2 hours per week at another job (range, 2 to 40 hours). The respondent characteristics are representative of Maryland dentists and are similar to other published demographic profiles of dentists.13-16,19,20 The dentists reported an average of one HIVinfected person seen at their office each week (range, 0 to 30) out of a mean of 103 patients (range, 4 to 500 patients per week). Knowledge. Knowledge scores, as determined using a well-defined AIDS knowledge scale, were noted to be generally very high: 96% of respondents were very knowledgeable about UP practices and 82% scored high on an HIV/AIDS general knowledge set of questions.21 However, only 35% of dentists scored high on a set of questions dealing with alternate modes of transmission (e.g., “HIV may be transmitted through mosquitoes”).21 Some deficiencies were also noted with respect to knowledge regarding transmission within the dental setting. For example, 44% of respondents thought that HIV could be transmitted through direct contact (intact skin) with an infected patient’s saliva, and 67% thought that HIV could be transmitted through a splash to the dentist’s eyes or mouth, both of these routes are extremely unlikely. Most dentists (79%), however, thought it was possible for HIV to be transmitted from visibly contaminated dental equipment and materials. And dentists were familiar with the risks associated with hepatitis B virus; only a small number of the dentists, 4%, did not think hepatitis B virus could be transmitted through contaminated instruments. Psychosocial variables
Risk perception and fear. Most dentists did not perceive themselves to be at risk of infection with bloodborne pathogens; only 15% thought that their risk was high. However, 28% reported high levels of fear of contagion. Ten percent of dentists said that they would not treat a patient known to have HIV, and 11% said they would not treat a
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patient known to have hepatitis B virus infection. Eighteen percent of respondents agreed with the statement “the medical profession is not telling everything it knows about AIDS.” Attitudes toward patients with HIV/AIDS. Most dentists (69%) scored high on a well-characterized HIV/AIDS attitudes scale, indicating that they were generally tolerant and accepting of patients infected with HIV or diagnosed with AIDS, although 43% said they would prefer to refer HIV-infected patients elsewhere.22 Fifty-six percent of respondents believed health care workers should have the right to refuse to treat HIV-infected patients. Efficacy of prevention. A very high percentage of dentists (98%) believed that adopting IC practices would protect them from exposure. For example, 98% of dentists “agreed” or “strongly agreed” with the statements “I can reduce my risk of occupational HIV infection by complying with UP” and “If UP are followed with every patient, my risk of HIV/AIDS will be very low.” Conflict of interest. We have previously shown that compliance with self-protective behaviors is especially poor if health care workers believe they cannot provide optimal patient care and still protect themselves from exposure to bloodborne pathogens.23 We refer to this construct as “conflict of interest.” The overall mean score on the “conflict of interest” scale (four items) for all dentists was 0.83 ± 0.60 (range, 0 to 4), indicating that few dentists perceived a conflict between providing care to patients and taking care of themselves. For example, only 14% believed that “the patients’ needs come first.” Work stress. Previously, we have shown an inverse correlation between high levels of work stress and the adoption of safe work practices.23 Work stress was measured by using an 18-item scale adapted from Revicki’s Work-Related Stress Inventory (WRSI).24 The mean score for this scale was 1.97 ± 0.47 (range, 1 to 4), indicating a moderate level of work stress. Examples of items included: “I occasionally hide in my office from others to shut them out,” and “It seems like I cannot get the recognition I deserve.” Sixty-six percent of dentists reported being “very satisfied” with their work. Organizational/management factors
Examples of relevant organizational-level factors that we previously found significantly associated with the adoption of safe work practices include the attitude toward safety management in the practice, the provision of safety training, the availability and accessibility of personal protec-
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tive equipment, general environmental conditions, and interpersonal relations in the workplace, as noted later in this article.23 Attitudes toward safety management. Respondents generally rated the overall safety management of their practices as good. For example, 62% agreed with the following statements: “The protection of workers from occupational exposure to HIV is a high priority for me,” “In my office, all reasonable steps are taken to minimize hazardous job tasks and procedures,” and “Where I work, unsafe work practices are corrected by me.” Training and personal protective equipment. Many dentists reported having received extensive training on IC practices in the previous 12 months. For instance, 57% reported receiving 6 or more hours of IC training, 23% reported 3 to 5 hours, 16% reported 1 to 2 hours, and only 4% reported that they had not received any IC training in the previous 12 months. Most of their training was in the form of written materials, although attendance at training films was also cited as a resource, as well as attendance at conferences. It should be noted that Maryland dentists are required to obtain continuing education credits on an ongoing basis. The provision of personal protection equipment was a high priority for dentists, with more than 98% reporting offering all the necessary equipment to their employees. Environmental conditions. Because we previously found an association between general working conditions and the adoption of safe work practices, we included several questions regarding the environmental conditions in the practice.23 Temperature extremes in the office were the most common complaint of the dentists, with 31% reporting that they were “always” or “often” uncomfortable because of temperature extremes at work. Other environmental conditions that were found to be a source of discomfort included loud noises (16%), poor lighting (13%), and unpleasant odors (11%). Injuries/exposures. Dentists frequently reported exposure to patients’ blood and saliva. For example, 28% of respondents reported either parenteral or mucocutaneous exposure to patients’ saliva or blood in the previous 6 months. Of these, 4% involved HIVcontaminated blood. Seven percent (n = 27) of the dentists reported one or more contaminated needlesticks in the previous 6 months, and, of these, only 3% received any treatment or follow-up for their exposure. Twelve percent of the dentists reported getting splashed in the previous 6 months and 16% reported one or more sharps-related injury.
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Table 1. Proportion of dentists who reported compliance with individual IC practices (n = 392)
Practice
1. Disposal of sharps into sharps containers 2. Refrain from recapping contaminated needles (using the two-handed method) 3. Washing hands after removal of gloves 4. Wearing outer protective garments 5. Wearing disposal gloves 6. Use of protective eye shields 7. Use of face masks 8. Disposal of contaminated materials 9. Cleaning of patient-related spills promptly 10. Refraining from eating while treating patients 11. Using extreme caution with sharp instruments 12. Treating saliva-contaminated materials (paper cups, etc.) as infectious
Percent responding “always”
87.9 37.0 59.1 37.2 97.6 80.8 79.7 82.1 84.0 80.9 90.0 64.7
IC practices
Thirty-six percent of the dentists reported that they “always” complied with each of the 12 IC items. Dentists were most compliant with proper sharps disposal practices (88%) and the wearing of disposable gloves (98%) and least compliant with refraining from recapping contaminated needles; 63% reported that they “always” recapped needles using the improper two-handed method. Other practices that had poor compliance included wearing protective clothing (37%), washing hands after the removal of gloves (59%), and wearing protective face masks (80%). Specific responses for each individual item on the scale are shown in Table 1. Most dentists reported they were personally responsible for the IC programs in their office, which many respondents characterized as quite extensive; for example, 90% had an office safety program, including written IC policies. Yet there were some discrepancies because although 97% of the dentists stated that strict compliance with IC practices was expected by their staff, only 79% of the dentists said that they always personally complied with IC practices. And although 96% of the respondents stated that disinfection and sterilization procedures were strictly adhered to, only 76% reported that they consistently sterilized all their handpieces. Almost all dentists (99%) believed that they set a good example regarding IC for the rest of their staff. Most (82%) of the dentists disposed of their regulated medical waste by shipping it to an off-site
incinerator, but a small fraction (8%) admitted to putting it into the regular trash. Finally, more than 90% of dentists reported making significant changes in their IC practices in the preceding 12 months, and 60% were currently satisfied with their IC program. Medical surveillance practices
A high percentage of dentists (97%) offered the hepatitis B vaccine to their staff, and a large percentage of dentists (84%) had personally received the vaccine. When asked whether they would take zidovudine as a prophylactic treatment after an HIV-contaminated needlestick, 37% said yes; however, only 7% thought that it would be effective in preventing infection. Univariate analysis—correlates of IC practices
Significant relationships were found between high levels of compliance with IC practices and the following factors: (1) tolerant attitudes toward HIV/AIDS patients (p < 0.05), (2) high levels of belief that IC practices were effective in exposure prevention (p < 0.05), (3) high scores on a test of general knowledge on HIV/AIDS (p < 0.05), and (4) positive attitudes of the dentist toward safety management within the dental practice (p < 0.001). Importantly, the history of exposure was also significantly associated with compliance (p < 0.05). Multivariate models
When the significant univariate items were entered into a hierarchical stepwise model, only two variables were determined to be significantly associated with compliance in multivariate analysis: (1) tolerant attitudes toward patients with HIV/AIDS (odds ratio [OR] = 1.72, CI95 = 1.05, 2.79) and (2) positive attitudes toward safety in the practice (OR = 2.72, CI95 = 1.70, 4.36). Individual factors, such as sociodemographic information and other organizational and psychosocial variables assessed in this sample of dentists were not found to be significantly associated with IC practices at the multivariate level. DISCUSSION
Improvements in dental IC practices have been steadily made since the start of the HIV epidemic. For example, in a 1986 nationwide study conducted by the American Dental Association it was reported that 80% of the respondents wore protective eyewear, 20% wore disposable gloves, 20% wore face masks, and 12% wore protective clothing when providing care for all patients.20 Gerbert19 reported in a 1987 study that 80% of respondents (n = 297) consistently wore gloves, 70% wore masks, 33% wore protective garments,
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39% sterilized handpieces, and 80% used disinfectants appropriately. In 1990 a report by Hazelkorn25 indicated that 87% of respondents reported that they wore gloves, and 89% reported that they wore masks. In 1991 the American Dental Association reported increases in all the following IC practices compared with their 1986 findings, rises on glove use (90%), the use of masks (60%), and the use of protective clothing (64%).26 In 1992 a report by Woo et al.27 indicated that 27% of the dentists in their study sterilized handpieces. Finally, in a study conducted by Feldman and Bramson in 1994,28 it was reported that in 92% of the U.S. dental practices they surveyed, consistent sterilization of handpieces was performed. In our study, glove use was reported to be 98%; 37% reported frequently wearing protective garments, 80% wore face masks, 84% used disinfectants, and 76% sterilized handpieces. Recapping has been a noted problem in the past for dentists because of the nature of the injections that they give (e.g., anesthetics), which are often given multiple times throughout a procedure, and we noted similarly high rates of recapping. Overtime, improvements have been made in the acceptance of the hepatitis B vaccine in the dental community. The Dental Division of the Indiana State Board of Health, which has been surveying Indiana dentists since 1985, found that vaccination was reported by 37% of dentists in 1985, but by 1988, 67% (n = 1200) had been vaccinated.29 In our sample, 84% of respondents reported that they had received the vaccine. Our finding that the two most significant correlations with compliance were tolerant attitudes toward patients with HIV/AIDS and strong safety management programs is important because it provides direction for intervention strategies. In an earlier study we identified several important determinants of tolerant attitudes toward patients with HIV/AIDS; these were (1) personally knowing someone who was infected with HIV or who had been diagnosed with AIDS, (2) high scores on tests that measured general HIV/AIDS knowledge and alternate modes of transmission (casual contact), (3) low levels of fear of contagion, and (4) accurate perceptions of risk of occupational infection.30 Many of these determinants can be readily addressed through appropriate and targeted educational programs. Dentists wishing to improve the overall safety management of their practice should conduct periodic safety management audits to assess their current status and then
make adjustments accordingly (contact corresponding author for information on resources). Finally, our finding that overall compliance with IC practices was found to be associated with exposure is consistent with other health care workers who also showed this relationship.31,32 Although caution must be exercised in comparing studies conducted at different times, with different dental populations, and with different instruments, our data confirm a trend in improvements in IC practices that continues to be made within the dental community. These findings indicate that although room for improvement still exists, important advances in this area appear to have been made. Although our findings are encouraging, they must be viewed with some reservations. First, selfreports, even confidential ones, may seriously overestimate socially desirable responses. Second, despite extensive follow-up procedures, only 60% of our sample responded to the questionnaire, thus raising the issue of self-selection bias; dentists who responded to the questionnaire may have been more concerned about IC issues than nonrespondents and thus more likely to be more conscientious about IC. However, our sample’s demographics were similar to that of Maryland dentists as a whole, perhaps indicating that the respondents were representative of Maryland dentists. However, Maryland dentists may not be representative of dentists as a whole (self-selection bias). Despite these caveats, we remain optimistic and confident that important improvements in IC practices continue to be made in the dental community. It will be important to reevaluate this issue to determine whether improvements continue. We thank Sylvia Cohn for statistical assistance, Meghan Dunleavy for research assistance, and Patricia Flanagan for editorial assistance.
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34 Gershon et al. 5. Centers for Disease Control. Recommendation for preventing transmission of infection with human T-lymphotropic virus type III/lymphadenopathy-associated virus in the workplace. MMWR Morb Mortal Wkly Rep 1985;34:681-6,691-5. 6. Occupational Safety and Health Administration. Final standard for occupational exposure to blood borne pathogens: December 6, 1991. 29 CFR 1910.1030. 7. Centers for Disease Control. Recommended infection control practices for dentistry. MMWR Morb Mortal Wkly Rep 1986;15:237-42. 8. Centers for Disease Control. Recommendations for prevention of HIV transmission in health care settings. MMWR Morb Mortal Wkly Rep 1987;36(Suppl 2s):1s-16s. 9. Centers for Disease Control. Update: universal precautions for prevention of transmission of human immunodeficiency virus, hepatitis B virus, and other bloodborne pathogens in health care settings. MMWR Morb Mortal Wkly Rep 1988;37:377-82,387-8. 10. Centers for Disease Control. Guidelines for prevention of transmission of human immunodeficiency virus and hepatitis B virus to health care and public safety workers. DHHS (NIOSH) Pub. No. 1-46. Atlanta, GA, 1989. 11. Centers for Disease Control. Recommended infection control practices for dentistry. MMWR Morb Mortal Wkly Rep 1993;42:1-12. 12. Centers for Disease Control. Possible transmission of human immunodeficiency virus to a patient during an invasive dental procedure. MMWR Morb Mortal Wkly Rep 1990;39:489-93. 13. Hazelkorn HM. Do dentists have sufficient information about their patients to control infection? J Dent Educ 1990;54:149-52. 14. Dorsey M, Overman P, Hayden WJ, et al. Relationships among and demographic predictors of dentists’ self-reported adherence to national guidelines. Soc Sci Med 1991;32:1263-8. 15. Hardie J. The attitudes and concerns of Canadian dental health care workers toward infection control and the treatment of AIDS patients. J Can Dent Assoc 1992;58:131-8. 16. Passannante MR, French J, Louria DB. How much do health care providers know about AIDS? Am J Prev Med 1993;9:6-14. 17. Cronbach LJ. Coefficient alpha and the internal structure of tests. Psychometrika 1951;16:297-334.
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18. Likert R. A technique for the measurement of attitudes. Arch Psychol 1932;140:1-55. 19. Gerbert B. AIDS and infection control in dental practice: dentist’s attitudes, knowledge and behavior. J Am Dent Assoc 1987;114:311-24. 20. Verrusio AC, Neidle EA, Nash KD, et al. The dentist and infectious diseases: a national survey of attitudes and behavior. J Am Dent Assoc 1989;118:553-62. 21. National Center for Health Statistics. AIDS knowledge and attitudes. Vital Health Stat 1988;161(3):1-12. 22. Shrum JC, Turner NH, Bruce KE. Development of an instrument to measure attitudes toward acquired immune deficiency syndrome. AIDS Educ Prev 1989;1:222-30. 23. Gershon RRM, Vlahov D, Felknor S, et al. Compliance with universal precautions among health care workers at three regional hospitals. Am J Infect Control 1995;23:225-36. 24. Revicki DA, May HJ, Whitley TW. The health professional stress inventory: development and validation. Greenville (NC): East Carolina University; 1988. 25. Hazelkorn HM. Do dentists have sufficient information about their patients to control infection? J Dent Educ 1990;54:149-52. 26. Nash KD. How infection control procedures are affecting dental practice today. J Am Dent Assoc 1992;123:67-73. 27. Woo J, Anderson R, Maguire B, et al. Compliance with infection control procedures among California dentists. Am J Orthod Dentofac Orthop 1992;102:68-75. 28. Feldman MC, Bramson JB. What is the cost of compliance? J Am Dent Assoc 1994;125:682-6. 29. Mollenkopf JP, Smith CE. Indiana dentists’ acceptance of universal precautions. J Ind Dent Assoc 1990;69:29-33. 30. Gershon RRM, Curbow B, Kelen G, et al. Correlates of HIV/AIDS-related attitudes among hospital workers. Am J Infect Control 1994;22:293-9. 31. Wong WS, Stotka JL, Chinchilli VM, et al. Are universal precautions effective in reducing the number of occupational exposures among health care workers? A prospective study of physicians on a medical service. JAMA 1991;265:1123-8. 32. Beekmann SE, Vlahov D, Koziol D, et al. Temporal association between implementation of universal precautions and a sustained, progressive decrease in percutaneous exposures to blood. Clin Infect Dis 1994;18:562-9.