Aerosol and splatter production by focused spray and standard ultrasonic inserts

Background: Control of contamination in the dental office has sometimes deterred practitioners from using ultrasonic scalers. Recent studies point to the aerosol and splatter produced during ultrasonic scaling as a vehicle for the possible transmission of bloodborne pathogens. A recently introduced ultrasonic insert that focuses the spray produced during scaling may reduce this aerosol contamination. An aerosol reduction device (ARD) that is attached to the ultrasonic handpiece has been shown to reduce the contamination cloud by placing suction in close proximity tc, the ultrasonic tip. The purpose of this study was to compare the contamination produced by a standard insert (S) and the new focused spray (F) insert with and without the use of the aerosol reduction device (ARD). Methods: The testing was conducted in vitro within a plastic enclosure using a dye in the coolant spray. After mock scaling of a dentoform model, the number of contaminated squares on the enclosure was counted and recorded. Results: Analysis of the data indicated no significant difference (P >0.05, Mann-Whitney U test) between the S or F inserts in the amount of contamination produced. When the aerosol reduction device was used, there was a significant reduction (P <0.05, Mann-Whitney U test) in the amount of contamination for both inserts with a greater reduction for the standard insert. Conclusions: The traditional style of ultrasonic insert (S) and the newer focused coolant water insert (F) produce an equal amount of aerosol contamination. The amount of aerosol contamination produced by both inserts is copious. The ARD significantly reduced contamination with both styles of inserts. These findings support the use of a large bore high-volume evacuator whenever an ultrasonic scaler is used.