Occlusal Sound-Wave Detector

Abstract

Not much study has been reported concerning the clinical application of occlusal sound for examination and diagnosis of occlusion. Stewart (1953), Thompson (1954), Schwontz (1959), and Silverman (1962) stdied the tooth contact sounds and the TMJ sounds by means of the stethosope or by directly listening to those. Those me thods, however, did not provide reliable results for they did depend entirely upon the listener's auditory sense.
In order to analyze the occlusal sounds in much objective manner, Watt (1967) and Brenman (1972) developed the new methodslogy, of which the visual records of sound of occlusion was possible. Occlusal sound was picked from the bone transmission sound by microphone and was transduced to the electrical signals and displayed on the magnetic oscilloscope or Braun tube oscilloscope. Figures displayed may be stored in the pen-recorder or pictured. Brenman (1972) developed occlusograph being applicable for occlusal analysis in clinical dentistry.
Several studies have been reported concerning the occlusal sounds on the Japanese journals of prosthodontics or other dental associations since 1960s. Author developed two types of the occlusal sound wave detector, namely DENTAL sound CHEKER 201 and 202, in 1976 and 1977, respectively. In those detectors, Occlusal sound wave was picked by the microphone, and the amplitude, duration, dispanity in impact time and so on, were observed so as to examine stability of tooth contact.
In spite of excellent clinical performance of the occlusal aound wave detecter, there still are a few problems such as the obscrity or the resonance of the sounds through the body structure. This article dealt with the analysis of the occlusal sound waves displayed on the detector.