Atmospheric contamination during ultrasonic scaling

Abstract
Objective: The aim of this study was to determine the microbial atmospheric contamination during initial periodontal treatment using a piezoelectric ultrasonic scaler in combination with either high‐volume evacuation (HVE) or conventional dental suction (CDS). Methods: The study included 17 treatment sessions, consisting of a 40‐min episode of continuous plaque and calculus removal using an ultrasonic unit (EMS). The treatment sessions were carried out in six patients with generalized adult periodontitis and ranged from two to four sessions per patient according to their needs. The use of HVE and CDS was randomly assigned over the sessions within each patient. Before each treatment, the operating room was not used for 15 h. To measure baseline microbial air pollution two Petri dishes containing blood agar were exposed for 10 min to the air. At the start of each treatment session, two Petri dishes were exposed for 5 min at a distance of 40 cm from the mouth of the patients. After 20 min, this procedure was repeated. At a distance of 150 cm, two Petri dishes were exposed for 20 min followed by exposure of two new Petri dishes for the rest of the session. The plates were cultured aerobically and anaerobically for 3 and 7 days, respectively. Results: The mean colony forming units (CFU) before treatment never exceeded 0.6 colonies per plate. At 40 cm, the mean CFU, when considering a period of 40 min, was 8.0 for HVE and 17.0 for CDS. The mean CFU at 150 cm during this period was 8.1 with HVE and 10.3 with the CDS. With reference to the Air Microbial Index the operatory atmosphere was considered to be in a good condition during 40 min of continuous use of the ultrasonic scaler in combination with both HVE and CDS. Conclusion: Within the restrictions of this study, only limited atmospheric microbial contamination is produced when using a piezoelectric ultrasonic scaler.