Objectives: Effect of noise in daily life and activities is known for more than two millenia. In recent years there have been proposals to consider the effects of noise on population on a 24-hour period. Today noise is one of the most frequently measured parameters in industrial hygiene applications. Although the importance of continuous exposure is known and reported for work environments, the impact sources in our daily activities are passed unnoticed. Most dentistry students in Turkey have to go through a preclinical practice in which they use laboratory handpiece during their education. These students are exposed to semi-continuous noise during their one semester practical training on endodontics. Methods: In this study we monitored the noise levels in a laboratory, during the laboratory session. The impact of noise on 18 students were monitored before and after the laboratory session via audiometric examination. The purpose of the study was to determine the noise level in a noisy dental school training laboratory and also to investigate known but ignored impact of low level noise exposure on young people. Results: Our findings indicate that (i) laboratory environments have noise levels comparable to industrial work places, (ii) Each student experienced temporary hearing loss after practice sessions, (iii) impact on hearing depends on the location of the source. Conclusions: Based on these findings, in order to limit unwanted effects of noise, we advice dentistry students and academic staff to take precautions as to minimize clinical noise (in particular, noise generated by the drills), and to use protective gear during practice sessions. Unnoticed noise sources are briefly identified and the importance of eliminating such noise sources in our daily life is stressed.