title: Efficacy versus health risks: An in vitro evaluation of power-driven scalers.
abstract: BACKGROUND
  Power-driven instrumentation of root surfaces during supportive periodontal therapy is an alternative to hand instrumentation. The purpose of this pilot in vitro study was to investigate the efficacy of sub- and supragingival plaque removal with a sonic (AIR: Synea, W and H, Bürmoos, Austria) and two ultrasonic devices (TIG: Tigon+, W and H, Bürmoos, Austria; VEC: Vector, Dürr, Bietigheim-Bissingen, Germany) as well as the health-risk for dental professionals during treatment.
  
  
  METHODS
  The power-driven devices were utilized to remove plaque from model teeth in dummy heads. The percentage of residual artificial plaque after 2 min of supra- or subgingival instrumentation was calculated by means of image-processing techniques at four sites (n = 576) of each tooth. The Health-Risk-Index (HRI: spatter/residual plaque quotient) with the different power-driven devices was assessed during treatment.
  
  
  RESULTS
  The smallest amounts of residual plaque were found for the sonic device AIR (8.89% ± 10.92%) and the ultrasonic scaler TIG (8.72% ± 12.02%) (P = 0.707). Significantly more plaque was remained after the use of the ultrasonic scaler VEC (18.76% ± 18.07%) (P < 0.001). Irrespectively of the scaler, efficacy was similar sub- (10.7% ± 11.6%) and supragingivally (13.5% ± 17.2%) (P = 0.901). AIR/TIG demonstrated equal residual amounts of plaque sub- (P = 0.831) as well as supragingivally (P = 0.510). However, AIR/VEC and TIG/VEC were significantly in favor of AIR and TIG (P < 0.001). In contrast, the lowest HRI was found after using VEC (0.0043) and differed considerably for AIR (0.2812) and TIG (0.0287).
  
  
  CONCLUSIONS
  Sonic devices are as effective as ultrasonic devices in the removal of biofilm but bear a higher risk to the dental professional's health concerning the formation of spatter.
authors: Department of Conservative Dentistry and Periodontology, School of Dental Medicine, University of Kiel, Kiel, Germany.
authors: Christian
authors: C
authors: Graetz
authors: Department of Conservative Dentistry and Periodontology, School of Dental Medicine, University of Kiel, Kiel, Germany.
authors: Anna
authors: A
authors: Plaumann
authors: Department of Conservative Dentistry and Periodontology, School of Dental Medicine, University of Kiel, Kiel, Germany.
authors: Jule
authors: J
authors: Bielfeldt
authors: Department of Conservative Dentistry and Periodontology, School of Dental Medicine, University of Kiel, Kiel, Germany.
authors: Anica
authors: A
authors: Tillner
authors: Department of Conservative Dentistry and Periodontology, School of Dental Medicine, University of Kiel, Kiel, Germany.
authors: Sonja
authors: S
authors: Sälzer
authors: Department of Conservative Dentistry and Periodontology, School of Dental Medicine, University of Kiel, Kiel, Germany.
authors: Christof Edmund
authors: CE
authors: Dörfer
keywords: Aerosol; dental prophylaxis; plaque; scaling