Contamination of Handpieces during Pulpotomy Therapy on Primary Teeth

Purpose: The purpose of this in vivo study was to determine the potential for internal bacterial contamination of low-speed handpiece/contra-angle systems. Methods: Clinical contamination was measured for 24 pulpotomies on primary first or second molar teeth from 20 subjects. The investigators used microbiologic analysis to determine the extent of bacterial contamination from the patient's saliva using enriched trypticase soy agar (ETSA) plates. Analysis for the presence of blood also occurred. Results: Microbial analysis indicated aerobic and anaerobic bacterial contamination at all 3 culturing sites from all 24 handpieces (100% contamination, 95% confidence intervals [CI]=86%-100%). Aerobic and anaerobic bacteria levels (CFU/mL) were not significantly different (P=.43 overall, P>.25 for each of the 3 evaluated sites). The sites also did not have significantly different CFU/mL levels (P=.13 overall, P=.63 for aerobic, P=.14 for anaerobic). The analysis showed no blood contamination at any of the 3 culturing sites for any of the 24 handpieces (0% contamination, 95% CI=0%-14%). Conclusions: The in vivo data suggest that low-speed handpiece/contra-angle systems can become bacterially contaminated during the performance of pulpotomies and, unless properly sterilized between patients, there is the potential for pathogenic micro-organisms to enter, adhere, and then emit during use on subsequent patients.