NOISE-LEVEL OF DENTAL HANDPIECES AND LABORATORY ENGINES

Impaired hearing in dental practitioners has been the subject of vario us investigations. Although individual age and susceptibility can play a significant role, the intensity of the noise, distance from the noi se source, and total duration of the noise are the important factors i n hearing. In this study the noise levels of different handpieces and laboratory engines were evaluated. Handpiece noise measurements were m ade while instruments were running free and during operation with vari ous cutting tools. These measurements were performed with two kinds of noise-measuring equipment: (1) a precision sound level meter and (2) a noise recording and analyzing circuit. The results indicated that (1 ) there were significant differences among the noise levels of the var ious dental engines used, (2) the tow-speed, angled-design handpiece h as the lowest noise level, whereas the laboratory engine has the highe st, (3) the noise level increases during cutting was compared with non cutting, and (4) there was no significant difference between the two m ethods of measurement.