[The effects of soft denture liners applied to complete dentures on masticatory functions]

The soft denture liner was applied to dentures for the edentulous patients with poor residual ridge and thin mucosa. It is useful for minimizing the soreness caused by the denture during mastication, however, its effect on masticatory functions has been rarely investigated. The purpose of this study was to determine the effect of a soft liner applied to complete dentures on masticatory functions. Five edentulous volunteers who were satisfied with their new complete dentures took part in this study. The lower dentures were lined with a soft liner. Comparison of occlusal force, masticatory performance, masseter muscular activity, and mandibular movement were made between new dentures and relined dentures. The results of applying soft materials to lower dentures obtained by comparison with complete dentures using hard acrylic resin bases were follows: 1. Occlusal forces were significantly larger (p < 0.01). 2. Masticatory performance in chewing peanuts increased slightly. The number of strokes and time for masticating a peanut decreased significantly (p < 0.01). 3. Masticatory muscles functioned more rhythmically and mandibular movements became smoother. 4. Integrated EMGs per stroke of all patients was similar.