Studies on Mandibular reference Position for Determining Occlusal Vertical Dimension -Influence of Thickness of Experimental Palatal Plate on Mandibular Position During Continuous [n] Phonation

The purpose of this study was to clarify the influence of an experimental palatal plate on the mandibular position during continuous [n] phonation and to investigate the applicability of the mandibular position for determining the occlusal vertical dimension. The first part of the study investigated the influence of an experimental palatal plate on the mandibular position during continuous [n] phonation in 20 subjects who had normal dentitions. The second part of the study investigated the influence of an experimental palatal plate on the mandibular position during continuous [n] phonation in 15 subjects who were complete denture wearers. The last part investigated the applicability of the mandibular position during continuous [n] phonation in establishing the occlusal vertical dimension in 5 subjects. The mandibular position was recorded with the aid of a mandibular movement analyzing device. The authors obtained the following results: 1. The interocclusal distance during continuous [n] phonation of the normal dentition were not significantly different between the normal condition and either of the two experimental conditions. 2. The interocclusal distance during continuous [n] phonation in complete denture wearers were not significantly different between the normal condition and either of the two experimental conditions. 3. The mean interocclusal distance during continuous [n] phonation was 0.8 ± 0.6 mm between either of the two and was close to 0.4 ± 0.4 mm of the normal dentition value. The results suggest that the mandibular position during continuous [n] phonation is not influenced by experimental palatal plates and is valuable for determining the occlusal vertical dimension.