[The influences of metal-ceramic restoration margins on gingival health].
OBJECTIVE: Today metal-ceramic restorations are widely accepted in dental practice because of their good aesthetic and biocompatible properties, but there are still several problems to be resolved, among which the influences of their margins on gingival health is noticeable. The purpose of this study was to investigate the influences of metal-ceramic restoration margin on gingival health. METHODS: 129 abutments of metal-ceramic restorations, including their margins' fitness, location and smoothness were examined and their influences on gingival health were analyzed. RESULTS: There was a close relation between the metal-ceramic restorations' margins and the gingival health. CONCLUSION: In order to maintain the gingival health, the margins should be smooth, closely fitted, no overhanging and in a moderate location (i.e. not below the gingival more than 1 mm).