[Noise level in dental laboratory practice].
OBJECTIVE
Dental technicians are exposed to different noises. The aim of this study was to determine the noise level produced by different dental laboratory handpieces and special equipments in one dental lab.


METHODS
The noise level produced by two dental laboratory handpieces(Kavo K9, NSK Vmax) was measured at distance of 15cm, 30cm and 45cm in free-running and different working conditions. Additionally, the noise level produced by some dental laboratory equipments and procedures were also measured both near the technician's ear and 1.5 meters away. The noise level was determined using a precious sound level meter.


RESULTS
The mean value of noise level of the two dental laboratory handpieces measured at all distances and in all conditions was between 61 to 83 dB. The noise level produced by some dental laboratory equipments were much higher, with high-speed metal cutting, steam cleaning and power pillo trimmer exceeding 90dB. Noise level inside the denture fabrication room was between 65 to 83 dB.


CONCLUSIONS
The noise level in the dental laboratory is considered to be a potential risk causing hearing loss. Regular audiometry checking up should be carried out among the dental technicians and ear protectors must be used during work.
Department of Prosthodontics, Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, China. doctorsunjian74@yahoo.com.cn
Jian
J
Sun
Jia-jing
JJ
Yao
Yi
Y
Tan
Fu-qiang
FQ
Zhang
D003754:Dental High-Speed Equipment; D006801:Humans; D007754:Laboratories, Dental; D009622:Noise; D009623:Noise, Occupational