Occupational exposures to blood in a dental teaching environment: results of a ten-year surveillance study.

Evaluation of occupational exposures can assist with practice modifications, redesign of equipment, and targeted educational efforts. The data presented in this report has been collected as part of a ten-year surveillance program of occupational exposures to blood or other potentially infectious materials in a large dental teaching institution. From 1987 to 1997, a total of 504 percutaneous/non-intact skin and mucous membrane exposures were documented. Of these, 494 (98 percent) were percutaneous, and 10 (2 percent) were mucosal, each involving a splash to the eye of the dental care worker (DCW). Among the 504 exposures, 414 (82.1 percent) occurred among dental students, 60 (11.9 percent) among staff, and 30 (6 percent) among faculty. One hundred ninety-one (37.9 percent) exposures were superficial (no bleeding), 260 (51.6 percent) were moderate (some bleeding), and 53 (10.5 percent) were deep (heavy bleeding). Regarding the circumstances of exposure, 279 (54.5 percent) of the injuries occurred post-operatively (after the use of the device), and most were related to instrument clean-up; 210 (41.0 percent) occurred intra-operatively (during the use of the device); and 23 (4.5 percent) occurred when a DCW collided with a sharp object in the dental operatory (eight cases involved more than one circumstance). The overall exposure rate for the college was 2.46+/-0.11 SD per 10,000 patient visits. The average rate for the student population was 4.02+/-0.20 SD per 100 person-years, with the highest rates being observed among junior year students. The observed rates of occupational exposures to blood and body fluids in this report are consistent with published reports from several other educational settings. Dental teaching institutions are faced with the unique challenge of protecting the student and patient populations against bloodborne infections. Educational efforts must go beyond mere teaching of universal precautions and should include the introduction of safer products and clinical procedures that can minimize the risks associated with the hands-on aspects of the students' learning process.