Psychophysical investigations of the preferred vertical dimension of occlusion in edentulous patients.
Two psychophysical methods were tested to obtain information on the long-term accuracy and stability of the vertical relation of occlusion as determined by the technique described by Lytle and Timmer (PVDO). One method (Békésy) was unsatisfactory. The other method (forced-choice) produced stable results. The data collected showed that, over a brief period of time, all test subjects could define their PVDO within a margin of less than 1 mm. Some subjects were unable to determine a precisely defined PVDO. These subjects also showed considerable variations in the PVDO over longer periods. Other subjects were able to establish a constant and remarkably stable value for the PVDO over many weeks. For these types of patients, precise determination of the vertical relation of occlusion is of the utmost importance.
D006801:Humans; D009066:Mouth, Edentulous; D011603:Psychophysiology; D013997:Time Factors