Abstract
Objectives: To assess awareness and prevalences of occupational health problems among oral health care workers in Edo State, Nigeria. Methods: This cross-sectional survey was conducted among oral health care workers working in two tiers of health care delivery in secondary and tertiary government-owned dental centres across Edo State from December 2008 to February 2009. A self-administered questionnaire was used to elicit information on demographic characteristics, awareness and prevalences of occupational problems, and preventive measures. Results: The response rate was 93.8%. Overall, 71.1% of respondents were dentists; other respondent groups included dental nurses and dental surgery assistants (16.7%), dental technologists (8.9%) and dental therapists (3.3%). The occupational health problem for which respondents reported the highest level of awareness was biological hazards (96.7%). The most commonly prevalent occupational health problems were musculoskeletal problems [wrist pain (66.7%), waist pain (76.7%), body pain or weakness (84.4%)]. Infection by biological hazards was reported by 6.6% of respondents, and included infection by HIV/AIDS (2.2%), hepatitis B (1.1%), tuberculosis (1.1%) and other infections (2.2%). Chemical hazards in the form of skin reactions to latex gloves (17.8%), camphorated p-monochlorophenol (CMCP, 8.9%), X-ray (7.8%) and other allergies (5.5%) were reported. A few respondents (2.2%) reported occupation-related malignancies. Overall, 52.2% of respondents possessed a health insurance policy, and 93.3% and 88.9% worked in environments they described as well ventilated and well lit, respectively. A quarter (25.6%) of respondents used a film-holder when taking intra-oral radiographs and 23.3% used protective ear plugs when working in close proximity to noisy machines. Conclusions: Occupational health issues were significant among oral health care workers in Edo State. Awareness of biological hazards was very high. However, musculoskeletal issues represented the predominant occupational problem, and their potential negative impact necessitates urgent educational and ergonomic intervention.
Key words: Occupational health, occupational hazards, musculoskeletal problems, oral health care workers, Nigeria
INTRODUCTION
Oral health care workers face several risks in the workplace daily, both knowingly and unknowingly. Although a few of these risks are inconsequential, many are very latent and may become chronic; these are termed ‘occupational illnesses’. Broadly grouped, these work-induced health issues or risks include, respectively, physical, biological, chemical and psychosocial conditions1. Physical occupational risks include musculoskeletal problems, which can range from back pain to neck pain caused by long hours of maintaining a suboptimal working posture, and wrist pains caused by the repetitive wrist movements involved in several dental procedures and difficult access in some cases. In addition, long working hours can lead to increased pressure on joints and the spinal cord, and reduced blood flow, causing back pain and muscle ischaemia2., 3., 4.. The dental working environment is home to very many biological hazards, and the threat of cross-infection in dentistry is significant and includes infection with diseases such as HIV/AIDS, tuberculosis, hepatitis B and many others that are easily transmitted through blood, saliva and the aerosol spray generated in the course of many procedures5., 6., 7.. There is also risk associated with the toxicity of chemicals routinely used in dentistry, such as formocresol, mercury in amalgam, amalgam and hydrogen peroxide. Radiograph developing chemicals and longterm exposure to radiation have longterm effects, and the use of latex gloves can also cause allergic reactions and other skin conditions in oral health care workers8., 9., 10.. Psychological and social issues related to the practice of dentistry include stress, anxiety, tension and fatigue11.
The impacts of occupational health problems in dentistry are varied. For example, musculoskeletal problems have been identified as reasons for early retirement, cancelled appointments and decreased productivity among oral health care workers12 with negative impacts on the quality of life of these workers. In addition, insomnia and other mental disorders have been reported in some cases. Fear of litigation increases psychological and economic pressure on oral health care workers in many countries in which government legislation makes it very easy for patients or their relatives to pursue legal retribution when they perceive that malpractice or a breach of agreement has occurred11., 13..
Awareness of these occupational hazards and the implementation of preventive strategies are necessary to provide a safe practice environment for all concerned. The World Dental Federation (FDI) advocates that every dental professional should employ safety and health standards. This recommendation is intended to prevent the occurrence of injuries at work, to support cross-infection control and to help sustain a healthy environment14.
Understanding the nature and prevalences of these risks will help in developing a model for occupational health and safety guidelines in oral health care delivery. However, the literature on occupational health issues in oral health care workers in Nigeria is scanty and has been conducted only in southwestern Nigeria13., 15.. These studies lacked information on levels of health care (whether primary, secondary or tertiary) because they were based in single, tertiary hospitals13., 15.. The objective of the present study was to assess awareness and prevalences of occupational health problems among oral health care workers in two tiers of health care delivery (secondary and tertiary) in Edo State, Nigeria.
METHODS
This survey was carried out in four hospitals in Edo State, Nigeria, spread across the geopolitical zones of the state and representing two tiers of health care delivery: tertiary and secondary. It was carried out between December 2008 and February 2009.
Site 1 was the University of Benin Teaching Hospital. This is a federal, tertiary health institution in Benin City, Edo-South. The hospital is the largest in midwestern Nigeria and employs more than 150 oral health care workers in various specialties and subspecialties.
Site 2 was the Central Hospital Benin City. This is a state-run, secondary care hospital in Benin City, Edo-South. Central Hospital is the largest arm of the hospital management board of Edo State, which comprises 10 hospitals scattered across the state. As the largest health employer in the state, Central Hospital Benin City employs about 40 oral health care workers.
Site 3 was the Irrua Specialist Teaching Hospital in Irrua. This federal, tertiary care hospital is the largest in the Edo-Central and Edo-North constituencies and serves these regions of the state. It is a teaching hospital with about 40 oral health care workers.
Site 4 was Central Hospital Fugar. This is a secondary health care hospital in Edo-North. It employs very few (about 12) oral health care workers.
The study population included all dental surgeons, dental surgery assistants (DSAs), dental nurses, dental therapists, technologists, hygienists, laboratory scientists and technicians in these hospitals. The survey was carried out using a self-administered questionnaire, which elicited information on demographic characteristics, awareness and prevalences of occupational health problems, and preventive measures. Approval for this research was obtained from the University of Benin Teaching Hospital Ethics Review Committee. Prior to the onset of the study, informed consent was obtained from all participants. The study was carried out in complete compliance with the World Medical Association’s Declaration of Helsinki16. Data analysis was conducted using spss Version 13.0 (SPSS, Inc., Chicago, IL, USA).
RESULTS
The response rate was 93.8%. The majority of respondents were male (54.4%), married (56.7%), aged 20–40 years (86.7%) and had < 10 years of work experience (67.8%). Most (71.1%) of the respondents were dentists; other groups included dental nurses/DSAs (16.7%), dental technologists (8.9%) and dental therapists (3.3%) (Table 1). The overall awareness of occupational hazards affecting oral health care workers was high. The highest level of awareness among respondents pertained to biological hazards, whereas the lowest level of awareness referred to legal hazards (Table 2). Musculoskeletal problems reported by respondents included wrist pain (66.7%), waist pain (76.7%) and body pain and weakness (84.4%). Biological hazards accounted for 6.6% of reported problems and included HIV/AIDS (1.1%), hepatitis B (1.1%), tuberculosis (1.1%) and other infections (2.2%). A total of 17.8% of respondents had experienced skin reactions caused by latex gloves (15.6%), camphorated p-monochlorophenol (CMCP)/formocresol (8.9%) and X-ray chemicals (7.8%). Only 2.2% of respondents reported occupation-related malignancies and 1.1% reported leukaemia(Table 3). About half (53.3%) of the respondents possessed a health insurance policy and 72.2% had been vaccinated against hepatitis B virus. Other preventive measures used included wearing gloves (87.5%), working in well-ventilated (72.2%) and well-lit (46.7%) environments, using a film-holder when taking radiographs (26.7%) and using ear protection when working in close proximity to noisy machines (13.3%) (Table 4).
Table 1.
Demographic characteristics of respondents. (Response rate = 93.8%)
| Characteristics | n | % |
|---|---|---|
| Age, years | ||
| 20–25 | 10 | 11.1 |
| 26–30 | 24 | 26.7 |
| 31–35 | 21 | 23.3 |
| 36–40 | 23 | 25.6 |
| 41–45 | 8 | 8.9 |
| 46–50 | 3 | 3.3 |
| > 50 | 1 | 1.1 |
| Sex | ||
| Male | 49 | 54.4 |
| Female | 41 | 45.6 |
| Marital status | ||
| Single | 37 | 41.1 |
| Married | 51 | 56.7 |
| Divorced | 1 | 1.1 |
| Widowed | 1 | 1.1 |
| Profession | ||
| Dental surgeon | 64 | 71.1 |
| Dental nurse/DSA | 15 | 16.7 |
| Dental therapist | 3 | 3.3 |
| Dental technologist | 8 | 8.9 |
| Years of experience | ||
| < 10 | 61 | 67.8 |
| ≥ 10 | 29 | 32.2 |
| Total | 90 | 100 |
DSA, dental surgery assistant.
Table 2.
Awareness of occupational hazards among respondents
| Type of hazard | Response to item as a hazard, n (%) | |||
|---|---|---|---|---|
| Agree | Disagree | I don’t know | No response | |
| Musculoskeletal | 85 (94.4) | 3 (3.3) | 1 (1.1) | 1 (1.1) |
| Biological | 88 (97.8) | 1 (1.1) | 1 (1.1) | 0 (0) |
| Chemical | 98 (97.7) | 2 (2.2) | 0 (0) | 0 (0) |
| Physical | 78 (86.7) | 7 (7.8) | 3 (3.3) | 2 (2.2) |
| Genetic | 72 (80.0) | 9 (10.0) | 6 (6.7) | 3 (3.3) |
| Legal | 65 (72.2) | 14 (15.5) | 6 (6.7) | 5 (5.6) |
Table 3.
Prevalence of occupational hazards among respondents
| Occupational health problem | Yes, n (%) | No, n (%) | No response, n (%) |
|---|---|---|---|
| Wrist pain | 60 (66.7) | 19 (21.1) | 11 (12.2) |
| Waist pain | 69 (76.7) | 17 (18.9) | 4 (4.4) |
| Body pain and weakness | 76 (84.4) | 11 (12.2) | 3 (3.3) |
| HIV | 1 (1.1) | 75 (83.3) | 14 (15.6) |
| Hepatitis B | 1 (1.1) | 75 (83.3) | 14 (15.6) |
| Tuberculosis | 1 (1.1) | 75 (83.3) | 14 (15.6) |
| Other infections | 2 (2.2) | 71 (78.9) | 17 (18.9) |
| Sharps injuries | 49 (54.4) | 33 (36.7) | 8 (8.9) |
| Reaction to latex gloves | 16 (17.8) | 62 (68.9) | 12 (13.3) |
| CMCP/formocresol | 8 (8.9) | 69 (76.7) | 13 (14.4) |
| X-ray chemicals | 7 (7.8) | 69 (76.7) | 14 (15.6) |
| Other allergies | 5 (5.5) | 69 (76.7) | 16 (17.8) |
| Mercury poisoning | 1 (1.1) | 75 (83.3) | 14 (15.6) |
| Leukaemia | 1 (1.1) | 73 (81.1) | 16 (17.8) |
| Malignancies | 1 (1.1) | 71 (78.9) | 18 (20.0) |
CMCP, camphorated p-monochlorophenol (used as an antiseptic in root canal treatment).
Table 4.
Preventive measures employed by respondents
| Preventive measures | Yes, n (%) | No, n (%) | No response, n (%) |
|---|---|---|---|
| Seminars | 71 (78.9) | 9 (10.0) | 10 (11.1) |
| Health insurance policy | 47 (52.2) | 28 (31.1) | 15 (16.7) |
| Adequate history | 86 (95.6) | 7 (7.8) | 7 (7.8) |
| Hand gloves | 87 (96.7) | 1 (1.1) | 2 (2.2) |
| Hepatitis vaccination | 84 (93.3) | 6 (6.7) | 0 (0) |
| Well-lit surgery | 80 (88.9) | 4 (4.4) | 6 (6.7) |
| Well-ventilated surgery | 84 (93.3) | 2 (2.2) | 4 (4.4) |
| Use of film-holder | 23 (25.6) | 51 (56.7) | 16 (17.8) |
| Clean amalgam spills | 66 (73.3) | 17 (18.9) | 7 (7.8) |
| Indirect vision | 68 (75.6) | 8 (8.9) | 14 (15.6) |
| Protective ear plugs | 21 (23.3) | 61 (67.8) | 8 (8.9) |
DISCUSSION
The World Health Organisation Declaration on Workers Health (2006) acknowledges that there is growing recognition of the relationships among working conditions, health and productivity, and states that: ‘…despite the availability of effective interventions for occupational health, too many workers are still exposed to unacceptable levels of occupational risks and fall victim to occupational diseases and work accidents, lose their working capacity and income potential’17. This tallies very well with the situation of oral health care workers in Nigeria; as this study confirms, oral health care workers in Nigeria continue to be exposed to work-related hazards and represent some of the 100 million new cases of occupational disease attributed to hazardous exposures or workloads reported annually worldwide18.
This study found that awareness of occupational hazards in the dental profession was as high as 96.7%. This may be explained by the fact that the majority of respondents had attended seminars on occupational health. The occupational health issue for which respondents expressed the highest level of awareness referred to biological hazards. This level of awareness may reflect the fact that a great deal of emphasis has been given to infection control in view of the high prevalence of hepatitis B infection in dental practice, in a similar way to the emphasis placed on HIV infection control. These findings are similar to those of a Jerusalem-based study19 which reported a high level of perception of the risk for biological hazards among dentists. Previous studies have also shown high levels of awareness of biological hazards such as HIV/AIDS among Nigerian oral health care workers13., 20.. Given this level of awareness, it is not surprising that as many as 96.7% of respondents in this study reported that they use gloves regularly.
Although the level of awareness of biological hazards was high in this study, exposure to HIV, hepatitis B, and tuberculosis was still reported. Although infection rates were as low as 1.1%, they are significant because of the morbidity and mortality associated with these infections. Despite high percutaneous exposure, the low prevalence of HIV infection documented in this study confirms the low transmissibility of HIV in dental practice. The low prevalence of hepatitis B may reflect the fact that a high percentage of respondents had been vaccinated. Further research to investigate the determinants of the occupational acquisition of these infections is important in order to develop optimal strategies for preventing it.
The use of universal or standard precautions has reduced but not totally eliminated the possibility of cross-infection in oral health care delivery, and the persistence of the occupational acquisition of infection among dental health professionals has been documented in the literature21. Compliance with standard precautions also has its own peculiar challenges. For example, the wearing of latex gloves is a primary precautionary measure aimed at preventing cross-infection. However, allergies and skin reactions to latex gloves remain common in dental practice. In this study, 17.8% of respondents had experienced skin reactions to latex gloves. This is lower than the 22.0% of dentists in southern Thailand22 and the 22.5% of dentists in Flanders, Belgium23 who reported a history of contact dermatitis caused mostly by the wearing of latex gloves. Other studies from around the world have reported hand dermatoses from dental materials24., 25.. In this study, rates of skin reaction to chemicals used for root canal treatment and X-ray processing were 8.9% and 7.8%, respectively. However, exposure to radiation while taking dental radiographs and longterm inhalation of formaldehyde from formocresol predisposes to leukaemia and other forms of cancer. This study found prevalences of leukaemia and other forms of malignancies both to be 1.1%. The prevalence of mercury poisoning from amalgam was also evaluated in this study. Hygiene practices in relation to the use of amalgam help to control mercury poisoning. Relatively good mercury hygiene practices may account for the low prevalence (1.1%) of mercury poisoning found in this study.
The utilisation of preventive measures against occupational hazards was fairly high except for the use of X-ray film-holders and protective ear plugs in noisy areas. Only 25.6% of respondents reported using X-ray film-holders when taking intra-oral radiographs. This poor practice may reflect the non-availability of equipment, the adverse consequence of which is the significant prevalence of leukaemia and other malignancies in this study. Fewer than a quarter of respondents used protective ear plugs, which may either reflect their non-availability or non-recognition of the fact that noise in dental practice is high enough to cause health problems among health workers.
The most outstanding occupational health issue in this study was musculoskeletal disturbance. Prevalences of musculoskeletal problems reported by respondents were 66.7% for wrist pain, 76.7% for waist pain and 84.4% for body pains and weakness. These high prevalences of musculoskeletal problems are consistent with findings from studies conducted elsewhere in Nigeria and other parts of the world3., 4., 13., 15., 22., 26., 27., 28., 29., 30., 31.. These incidences may be explained by the fact that long working hours and long hours of maintaining a specific posture lead to increased pressure on joints and the spinal cord, and reduced blood flow, causing back pain and muscle ischaemia2., 3., 4.. Wrist problems are predominantly caused by the frequent use of vibrating instruments, repetitive wrist movements and difficult access in some procedures.
As dentistry is a relatively young profession in Edo State, the outcomes of these musculoskeletal problems may prove serious because such problems have been implicated as the most important cause of early retirement in dentistry12 and are also an important cause of cancellations and decreased productivity. Eliminating this problem requires that the relevant authorities educate and train oral health care workers on posture during work and other protocols to prevent musculoskeletal problems.
Appointment cancellations and decreased productivity – fallouts of musculoskeletal disturbances – may also have other effects, specifically in terms of: litigation. Other causes of litigation may include unfavourable treatment outcomes, breach of agreement, malpractice and death during surgery as a result of negligence. However, legal action against health care workers is unpopular in Nigeria, which may account for the finding that the occupational hazard for which oral health care workers demonstrated the least awareness was litigation. Nevertheless, as other studies have shown, litigation in dental practice in Nigeria does occur13 and oral health care workers should obtain proper insurance policies as part of their strategy. This study found that only 52.2% of respondents possessed a health insurance policy. However, this is higher than the 13.2% reported in a previous study conducted among Nigerian oral health care workers13. The shaky nature of the National Health Insurance Scheme and the complete integration of Nigerian oral health care workers into the scheme currently remain unresolved32. The general perception of oral health care workers of their profession as hazardous33 is evidently not exaggerated; as this study shows, the profession chosen by oral health care workers involves many factors that impact on their physical, social and mental well-being and frequently severely stretch their job satisfaction and overall psychosocial utility.
CONCLUSIONS
The predominant occupational health problems found among oral health workers in Edo State in this study were musculoskeletal issues. This necessitates urgent educational and ergonomic intervention. The procurement and efficient use of X-ray film-holders and protective ear plugs are suggested as these methods would help to prevent the occurrence of malignancies and hearing impairment in workers. Further study on the determinants of occupational infection acquisition is also recommended.
Acknowledgements
The authors wish to acknowledge Dr Obarisiagbon Aimuamwosa (University of Benin Teaching Hospital, Benin City, Edo State, Nigeria) and Jossy Akhilumele (Irrua Specialist Teaching Hospital, Irrua, Edo State, Nigeria) for their support during data collection.
Conflicts of interest
None declared.
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