2013 Volume 5 Issue 1 Pages 47-55
Purpose: The aim of this study is to know the transmission of vibration of the dental motor in technical procedures and to protect dental technicians from vibration disease in hand and arm areas.
Methods: Sixteen candidates, dental technicians (male: 12; female: 4; 57.1 years old on average) who have no disease on their hand and arm areas, were involved this study. Two small 2-axis accelerometers are put on a motor and a finger. Vibration was measured when the subjects were carving dental stones and plastics at two places: the center of the handpiece motor and a finger. As a control, the vibration made by hand-writing was measured. The speed of the motor was set at 40,000 rpm and the point to carve was a carbide burr.
Results: In carving stones (0.089 G), greater acceleration was observed than inplastics (0.087 G) or in hand writing (0.068 G). No statistical differences were found between them. About absorption of the vibration, the stone showed greater value.
Conclusion: Because the absorption of the vibration was small in the low-frequency area (<8 Hz). it was concluded that vibration was well transmitted from the handpiece to the finger. The impact of the carving work was estimated to be around 23 times greater than the writing work, calculating by mass ratio.
