Abstract
The determination of the correct vertical and horizontal mandibular position for edentulous patients is one of the most important techniques in complete denture construction.
The aim of this study was to develop a new method of interocclusal record using exchangeable screw jack apparatus to determine the vertical dimension utilizing the patient's proprioceptive sensation. Furthermore, we expect to develop a method for tracing the Gothic arch and recording the centric jaw relationship which could be easily performed in a one-treatment procedure.
The exchangeable screw jack placed on the maxillary occlusal rim makes contact with a plate fixed on the mandibular occlusal rim. The height of each screw is adjusted as follows: from 3mm lower (score 1) than the vertical dimension of the present denture (score 4) to 3mm higher (score 7) at intervals of 1mm. Using the apparatus, the upper and lower borders of the comfortable occlusal zone (COZ) are calculated from the patient's perception of mandibular position by the constant method. To understand the reproducibility of the method, each COZ of 5 edentulous patients wearing complete dentures without problem was measured on 3 or 4 different days.
There is no significant difference between COZs of different measurement days. On the other hand, the time required for measurement and recording and the patient's stress were greatly reduced with the new apparatus.
