PERIO - Periodontal Practice Today
PERIO - Periodontal Practice Today 5 (2008), No. 4     4. June 2009
PERIO - Periodontal Practice Today 5 (2008), No. 1  (03.04.2008)

Page 51-55

The effect of water flow rate on ultrasonic scaler performance: in vitro evaluation
Lea, Simon C / Lightstone, Jonathan J / Landini, Gabriel / Walmsley, A Damien
Introduction:Applying load to an ultrasonic scaler tip can affect its vibrations. Cooling water flow-ing over such tips will also act as a load - though this is rarely considered inin vitro research inves-tigations. The aim of this study was to determine the effect of water flow rate on ultrasonic scalervibration.
Study design:The vibration displacement amplitude of three designs of scaler insert, including aSlimline tip, TFI-10 and TFI-3 (Dentsply, USA), were assessed unloaded and under 0.50 N and 1.00N load and with water flow rates of 20 ml/min and 40 ml/min. Vibration analysis was performed us-ing a scanning laser vibrometer.
Results:Increasing water flow rate from 20 ml/min to 40 ml/min caused a significant decrease (p < 0.0001) in all tip vibrations. Increasing water from 20 ml/min to 40 ml/min with the unloadedSlimline tip is equivalent to applying a 1.00 N load, and for the TFI-10 tip is equivalent to applyinga 0.50 N load in vitro.
Conclusions:Water flow rate has a significant influence on scaler tip vibration characteristics and isparticularly important for lighter, thinner tips such as the Slimline design. Future in vitroresearchmust consider the loading effect that water flow over ultrasonic scaler tips will have on their per-formance.

Keywords: performance, periodontology, ultrasonic scaler, vibration