A preparation method of working models

Abstract

It has been pointed out that crowns fabricated by the indirect method tend to be too high compared to the adjacent teeth at try-ins. According to Ohyama and Yuki, this excessive height at try-ins is caused by the physiological tooth mobility caused by occlusal contact with the crown made on a working model obtained in a resting state without occlusal contact. They recommend a method for manufacturing a prosthesis, which requires a little occlusal adjustment. With reference to this, we examined a working model adjustment method for cases with a few defects. After taking an impression, the occlusion is obtained using a silicone bite registration material; the omission of this silicone bite is carefully marked on the model; the bite material is divided and fitted; and the working model is adjusted with consideration for physiological tooth mobility and is mounted on an articulator with a bite material inbetween upper and lower models to obtain a tight fit—for crown fabrication. We tried to adjust such a working model. As a result, the amount of adjustment at the time of try-ins was significantly reduced, so it was suggested that the work model adjustment method for marking the omission of the bite material is effective.