| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Milieu in Dental School and Practice |
Key words: reporting, risk factors, occupational exposure, prevalence
Submitted for publication 04/02/07; accepted 06/13/07
 |
Abstract |
|---|
 Top Abstract MethodologyResultsDiscussionConclusionsReferences |
|---|
0.05. Of the total 167 individuals who had been exposed to biological material, 120 (71.9 percent) failed to report the accidents. The variables that were statistically associated with the nonreporting of occupational accidents were nonexposure to blood (OR=4.0; CI 95%: 1.7–10.0) and the fact that the students considered the exposure to be minor or of low risk (OR=8.8; CI 95%: 3.5–23.0) or considered the protocol adopted by the institution to be inadequate (OR=5.2; CI 95%: 1.2–17.1). The development of a procedure review policy is recommended with the aim of establishing continuous vigilance and encouraging the reporting of bloodborne exposure.
The area in which the dental professional works includes anatomically and functionally complex structures of difficult access and visualization. These structures have different forms and dimensions, are often positioned very close to one another, and are the gateway to other systems of the organism, as well as being rich in potentially pathogenic microorganisms. Dental procedures are performed in close contact between dentist and patient and require considerable skill in the use of sharp instruments, which creates a setting where provider and patient are vulnerable to accidents. Experience, dexterity, and skill contribute to reducing the risk of accidents resulting from unpredictable patient movements generated by physical or emotional discomfort during treatment. However, despite efforts to instill technical proficiency in undergraduate dental students by means of preclinical laboratory training before they begin to provide dental treatment for patients, students have variable levels of technical skill, and some are more prone to accidents than others.
Biological risk depends upon factors such as the presence and volume of blood, pathogenicity of the infectious agent, clinical conditions of the patient-source, susceptibility of the exposed person, and adequate post-exposure follow-up procedures.9,10 The evolution of knowledge on etiological agents, forms of treatment, and related factors has allowed the establishment of measures for reducing health risks stemming from accidents. It is recommended that exposure to blood and other potentially contaminated fluids be treated as a medical emergency.5 In order to achieve greater effectiveness, interventions for the prevention of infections from human immunodeficiency virus (HIV) and hepatitis B (HBV) need to be initiated immediately following occurrence of the accident.10
Following a percutaneous exposure involving blood known to be infected by HBV and the presence of HBeAg, which has a high rate of viral replication and therefore a greater quantity of circulating virus, the risk of developing hepatitis B ranges from 22 to 31 percent. The risk for hepatitis C is approximately 1.8 percent, ranging from 0 to 7 percent. With AIDS, the risk is 0.3 percent in percutaneous injuries and less than 0.1 percent in mucous membrane injuries.10,11 Because most injuries in dentistry are caused by small-gauge needles or compact instruments, dental professionals are exposed to a smaller volume of blood and, therefore, a lower risk.12 In spite of these data, a number of studies have found a high rate of underreporting of occupational accidents among undergraduate dental students.1,2,4,5,7,8,13
Notification generates further knowledge and contributes to measures of control and prevention. However, there is a lack of systematized data on occupational accidents involving biological material. Due to the underestimation of infection risk and the underreporting of exposure, there are no reliable estimates regarding contact with pathogenic bioagents. Such lack of knowledge on the extent of the problem hinders the implementation and evaluation of preventative measures. According to Younai et al., the investigation and documentation of circumstances of occupational exposure are crucial elements in the determination of risk factors.4
To address this gap in our knowledge, the aims of the present study were to investigate the prevalence of reporting occupational accidents involving blood-borne exposure in a dental school clinic and estimate the risk factors associated with the nonreporting of such accidents.
|
Methodology |
|---|
|
TopAbstractMethodologyResultsDiscussionConclusionsReferences |
|---|
The Federal University of Minas Gerais has an infection control policy, which was officially implemented in 1989 when a biosecurity commission was established. The post-exposure protocol consists of several key elements that determine that any occupational exposure to biological material should be reported and treated as a medical emergency. The affected individual should be sent to a medical care center.
A self-administered questionnaire consisting of thirteen open-ended questions and multiple choice items was used for data collection. The development of the questionnaire complied with all steps proposed by Streiner and Norman.14 Once the purpose of the study and its conceptual basis were defined, the generation of items was accomplished by means of a broad-based review of the literature, including questions used in preexisting instruments.4,5,15 Content validation was performed to determine the suitability of the theoretical content and functionality of the questionnaire. Item selection, adaptation, and new inclusions were then carried out based on the opinions of a judging commission made up of professionals from different dental institutions and specialties. The commission members were made aware of the objectives and methodology of the study and were asked to express their opinions in writing.16,17 For validation, unanimity in the approval of the questionnaire was required. Suggestions for changes were heeded when brought up repeatedly by different commission members. Response options were organized vertically. All items were formatted identically in order to avoid placing emphasis on any specific item. Space was included for suggestions or for the participants to express their thoughts if they did not encounter a satisfactory option.
Occupational exposure was classified into cutaneous, percutaneous, and mucous membrane, following the definitions established by OSHA.18 A pilot study was conducted in the semester prior to data collection with twenty students enrolled in the final semester of the course who were not part of the main sample. A final modification of the questionnaire was carried out based on the questions and suggestions that arose during the pilot study.
The questionnaire was divided into two parts. The first part was completed by all the participants and referred to demographic characteristics, records of occupational exposure, and the use of personal protective equipment (PPE). The second part was completed only by students who reported that they had suffered accidents. This part addressed information on the exposure variables such as the type of biological material, circumstances, items involved, and characteristics of the injuries. The complete version of the questionnaire appears in an article by Machado-Carvalhais.19
The data were collected during theory classes in the second semester of 2005. Participation was voluntary. Following the test-retest model to assess answer variations by the same respondent at different times, the same instrument was applied a second time to thirty students, corresponding to 10 percent of the sample. Agreement between responses on the two occasions was measured using the Kappa coefficient. Results ranged between 0.71 and 1.0, demonstrating a high degree of reproducibility of the answers and, consequently, a high degree of reliability.17,20 To calculate the denominator of the rate of occupational exposure per procedure, the institutional patient care archives were used.
Results were analyzed and compared by means of frequency and association statistical tests. The chi-square test was used to determine the association between reporting occupational exposure and the independent variables: biological material, circumstance in which accidents occurred, item involved, reason for failure to report, suggestions, and opinions for improving compliance with post-exposure protocol. The criteria for the selection of variables in the multivariate analysis (unconditional logistic regression) were obtained from the results of the univariate analysis (chi-square test). The Stepwise Forward Procedure was used to include variables with a statistical significance equal to or less than 10 percent into the logistic model based on their statistical significance. Variables remained in the model if they continued to be significant (p<0.05) and/or adjusted to the model.21 Exponential transformations were then undertaken to obtain the Odds Ratio (OR), and the chance of underreporting an occupational exposure to biological material was determined in the presence of the independent variables. The Statistical Package for the Social Sciences (SPSS) version 12.0 for microcomputers was used for the calculations.
The project was submitted to the Ethics Committee for Research on Human Subjects of the Federal University of Minas Gerais (UFMG) and authorization was given to conduct the study under the Protocol Number ETIC 038/05.
|
Results |
|---|
|
TopAbstractMethodologyResultsDiscussionConclusionsReferences |
|---|
Exposure to biological material was reported by 167 students (58.4 percent) and classified as cutaneous (34.3 percent), percutaneous (29 percent), and mucous membrane exposure (6.6 percent). Multiple exposures were reported by 27.2 percent of the interviewees, and 5.9 percent were exposed four or more times. These results correspond to a rate of 1.78 occupational exposures per student affected. The rate of reporting percutaneous occupational exposure was 9/10,000 procedures performed on patients.
Contact with blood and saliva occurred in 24.8 percent and 35.7 percent of the subjects, respectively. A total of 120 (71.9 percent) exposed students failed to report the accidents. Most of the subjects who filed reports only experienced a single accident. Among those who suffered multiple exposures, nine (5.4 percent) stated that they only reported one of these events, and two students (1.2 percent) reported more than one of their accidents.
Table 1
displays the frequency distribution related to the types of accidents, reporting of occupation exposure to biological material, and the post-exposure procedure adopted, as well as other variables. The main reasons given for non-reporting were that the exposure was minor or of low risk (75.2 percent) or that the student was following the advice of professors, employees, or fellow students (16.7 percent). Unawareness (14.2 percent) and lack of access to the protocol (10.8 percent) were also given as reasons for non-reporting. Most (83.8 percent) considered the protocol adopted by the dental school was inadequate. The main suggestions for improving compliance with the protocol were to offer medical treatment at the dental school itself (58.1 percent), better training of teachers (23.4 percent), reduction in operational difficulties (12.6 percent), improvement in means of transportation to the medical care center (7.8 percent), and improvement in the compatibility between the schedules of dental staff and students (7.2 percent). Despite being permitted to mark more than one option in the case of multiple exposures, a number of participants either did not know or did not express an opinion on some questions.
|
displays the associations with other independent variables. Variables related to handling sharp instruments (p=0.016)—specifically, hollow needles (p=0.006)—were significantly associated with reporting. Gender and age were not significantly associated with this variable (p>0.05). These data were calculated based on a final sample of 159 students, as there was a loss of 4.8 percent (n=8) due to failures to answer all the questions, which resulted in exclusion from the final sample.
|
).
|
|
Discussion |
|---|
|
TopAbstractMethodologyResultsDiscussionConclusionsReferences |
|---|
It should be pointed out that a cross-sectional study design with retrospective data collection by means of self-administered questionnaires could lead to the occurrence of memory bias as well as reverse causality, which suggests the need for further research using different study designs. Before considering whether the exposure may cause the outcome, we must consider whether the outcome may have caused the exposure. This concept is known as reverse causality.8,22
Occupational exposure rates have been expressed in terms of examinations for all dental care, persons per year, procedures, and other variations. This may hamper comparisons between results, but allows the evaluation of tendencies. Different studies may include undergraduates, postgraduates, and/or the entire team of professionals in the dental field.7 The rates found in the present study of 9/10,000 reports of percutaneous exposure in relation to the number of procedures performed (eighty-three reports for 93,892 procedures) and 12.8/10,000 consultations (eighty-three reports in 64,414 examinations for all dental care) are similar to findings in a prospective observational study carried out by Cleveland et al.23 Divergences with other results can be attributed to the methodology employed, as well as other factors. Lower rates were observed in studies based only upon reported accidents, which did not represent the totality of occupational exposure, such as findings by Ramos-Gomez et al. (3.53/10,000 consultations),1 Kennedy and Hasler (4/10,000 consultations),2 and Callan et al. (5.24/10,000 consultations).7 The influence of underreporting has also been demonstrated in studies by Younai et al. and Kotelchuck et al., carried out at the same dental school in New York. In the former, which was based on database records of occupational exposure from 1987 to 1997, an occupational exposure rate of 5.37/100 persons per year was observed among students in the third and fourth years of study.4 A considerable discrepancy was observed five years later, when Kotelchuck et al. found a rate of eight occupational exposure events/100 persons per year (±7.7/100), using anonymous questionnaire reports.5
Regarding the actions taken by students immediately following an accident, the majority (74.9 percent) of subjects washed the exposed site with soap and water, according to the recommendations of the Centers for Disease Control and Prevention. The use of antiseptic solutions by 24.6 percent of the undergraduate students should be considered with caution, as no additional benefit has been demonstrated over the use of neutral soap in such cases.11 Procedures that increase the exposed area and the application of caustic agents are not indicated. Furthermore, there is no study that justifies the expression of the exposed area, as observed in 22.2 percent of the cases, as a way of facilitating spontaneous bleeding.11
Multiple logistic regression analysis revealed that the students made decisions to not report accidents either based on the absence of blood (OR=3.9; CI 95%: 1.8–8.3) or on the lack of severity. This corroborates other studies that have shown that exposure considered minor or of low risk has a greater chance of not being reported (OR=8.8; CI 95%: 3.5–23.0).2,5
It is troubling that 57.8 percent of the percutaneous exposure events and 55.2 percent of accidents with hollow needles were not reported (Table 2
), because percutaneous exposure is the most efficient mechanism for the transmission of occupational infection.4 Furthermore, accidents involving needles with lumen may contain blood in the interior of the needle and offer greater occupational risks than needles without lumen.9 This fact is attenuated by the study carried out by Cleveland et al., who concluded that injuries involving suturing needles and small-gauge needles, such as those routinely used by dental surgeons, are classified as less severe, thereby offering a reduced risk of infection.12 Siew et al. point out that since most occupational exposure events are extra-oral, there is a lesser chance of an exchange of blood between the dental professional and patient; a change of gloves can be performed immediately without compromising the dental procedure.24
Accidents involving saliva had an increased chance of going unreported (OR=2.9; CI 95%: 1.4–6.0). These findings suggest that the infectious potential of saliva has been underestimated, even with the knowledge that blood may be present in the saliva, though not visible. Regarding the risk of hepatitis B transmission, although blood is the greatest source of the virus, it can also be found in other biological material, including saliva. Other infectious/contagious diseases, such as herpes simplex, tuberculosis, chicken pox, measles, and rubella, can be transmitted through saliva and are also considered risks of occupational infection for health care professionals.10,25
For eleven participants in the present study (6.6 percent), post-exposure occupational chemoprophylaxis (PEP) was recorded for the reduction of HIV transmission. This low prevalence may be based on the fact that most occupational exposure to HIV does not result in the transmission of the virus. Therefore, the PEP recommendation should be carefully weighed by considering the risk of infection along with the effectiveness and side effects of the medication. When indicated, PEP should be initiated as quickly as possible within the first hours following the accident, which did not occur in three cases (1.8 percent). Studies on animals suggest that protection is incomplete when initiated twenty-four to forty-eight hours after exposure.11 Thus, the measure to be considered is the use of rapid tests for the detection of anti-HIV antibodies in the source. As these tests have high sensitivity and specificity, they can help avoid initiating the prophylactic regimen or the unnecessary continuation thereof. Regarding prophylaxis for the reduction of hepatitis B transmission, which was recorded by just one student, greater effectiveness has been observed when the immunoglobulin is used within the first twenty-four to forty-eight hours following the accident. There is no proven benefit if administered one week after exposure.11,12
The fact that the students considered the protocol inadequate was independently associated with non-reporting (OR=5.2; CI 95%: 1.2–17.1) and is likely related to the fact that care for the affected subject was administered far from the accident site. Most of the students (58.1 percent) suggested that medical evaluation be performed at the school itself as a principal measure for optimizing compliance with the post-exposure protocol. The negative experience can be verified in the low repeat rate of reporting (6.6 percent).
According to Kotelchuck et al., students feel disheartened regarding compliance with protocol when acting without supervision or institutional support.5 In our study, the suggestions presented to optimize compliance with the post-exposure protocol, such as compatibility between schedules of hands-on classes and those of dental clinical support staff (7.2 percent) and the availability of transportation (7.8 percent), may reflect a lack of logistical support. These findings are corroborated by other studies that relate a high prevalence of accidents during the cleaning of instruments following patient care, when many dental support staff are not present in the clinics.1,4
Despite the reasons given by students for non-reporting, it is concluded that negligence in the reporting of exposures does not depend on infrastructure, but on individual responsibility. Certain reflections are necessary when 14.2 percent of the students stated unawareness of the protocol as the reason for not reporting accidents, and 16.7 percent said they were following the advice of professors, dental support staff, and classmates. The promotion of training aimed at reinforcing the measures of the Standard Precautions, the establishment of joint multidisciplinary actions directed at reducing accident-related health risks, and the exchange of experiences with occupational accidents are preventive, persuasive strategies that can be adopted to reinforce the importance of reporting exposures. Providing the opportunity for shared experiences to address problems of a practical nature gives rise to changes in behavior and may enhance a sense of personal responsibility among students for minimizing infection risk, thereby preparing them for professional life. Empowerment, as expressed in positive autonomy, signifies acquiring the ability to act effectively on the determinants of occupational risks in favor of prevention for an improved quality of life.26,27
Students who suggested the training of professors with regard to the post-occupational accident protocol exhibited a greater chance of not reporting accidents (OR=5.0; CI 95%: 1.5–16.9; p=0.009). This stresses the role of the professors as references and speaks to the fundamental importance of faculty members’ reviewing their beliefs, attitudes, and conduct so that they may be effective agents of change for their students.
Other interventions should also be stressed, such as reducing the operational difficulties involved in the post-exposure protocol, as suggested by 12.6 percent in of the participants, low and the constant monitoring of the occurrence of accidents with the ever-present aim of prevention, improved rates of accident reporting, and adequate post-exposure follow-up procedures. The reality of the risks associated with the importance of reporting occupational exposure should be more effectively divulged.28
In comparing reports of occupational exposure and reporting rates among dental students at a U.S. dental school, Wood et al. stated the evident combination of some not-yet-fully understood factors intercede between clinical events, identification, and management in the post-exposure protocol established by the school. According to these authors, the psychological constructs that involve the "fear of occupational exposure" and the personal interpretation of the significance of occupational exposure are probably among the factors that influence the belief in reporting.8
One must consider that methodologies that rely on formalized knowledge and are based on biological determinism do not address the social issues (socioeconomic factors, culture, ethnicity, etc.) that are historically constructed. The perception of these important indicators, which are capable of either sustaining or failing preventive behavior, is reflected in daily practices on the part of both teachers and students as well as other health care professionals involved in the exercise of their occupations in the teaching-learning process.29 This is a realm beyond that of linear rationality: it is not enough to inform and disseminate; knowledge of content in and of itself is not sufficient. It is necessary to mobilize, sensitize, involve, and encourage participation, thereby creating the conditions for a critical standpoint grounded in greater objectivity and not merely upon common sense.
The findings reported from this study indicate there is yet a long road to be traveled with regard to the reporting and prevention of occupational accidents involving exposure to biological fluids. It is necessary to encourage reporting on all levels, from the individual as well as the institutional perspective. As notification is considered a "measure of the sensitivity of the system," promotion and health assistance services should be integrated in an information and vigilance network for occupational exposure involving biological material. Only reliable estimates regarding contact with pathogenic agents permit the identification and knowledge of the extent of the problem. Such knowledge can then be used to improve strategies and optimize efforts.30
|
Conclusions |
|---|
|
TopAbstractMethodologyResultsDiscussionConclusionsReferences |
|---|
|
Footnotes |
|---|
|
REFERENCES |
|---|
|
TopAbstractMethodologyResultsDiscussionConclusionsReferences |
|---|
This article has been cited by other articles:
|
|
 |
|
  H. P. Machado-Carvalhais, M. L. Ramos-Jorge, S. M. Auad, L. H.P.M. Martins, S. M. Paiva, and I. A. Pordeus Occupational Exposure to Potentially Infectious Biological Material in a Dental Teaching Environment J Dent Educ., October 1, 2008; 72(10): 1201 - 1208. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
