Measurement of Occlusal Contact Area Effective in Mastication.

摘要

An instrument has been developed for measuring the effective occlusal contact area of molar and premolar teeth of one side of the mouth. Subjects are instructed to bite in centric occlusion on a special strip of wax consisting of cellophane fused between two layers of soft opaque wax. Light is passed through this occlusal registration in a cylinder containing a light bulb and two photovoltaic cells. The total quantity of light which passes through tranluscent areas of the registration is measured on a galvanometer whose scale is calibrated to read in square millimeters of effective occlusal contact area. Area measurements have been made on molar and premolar teeth of 50 subjects. Individual teeth in the registration were blacked out, and the area provided by each tooth was determined by the difference in readings. The area of corresponding maxillary and mandibular teeth did not differ significantly. The average effective occlusal area was 34.8 square millimeters for all subjects and 48.4 square millimeters for those having a complete dentition.