Abstract
AIM: The aim of the study was to evaluate the effect of feather-edge finish line and deep chamfer finish line on gingival position and marginal adaptation.
METHODS: Thirty patients requiring restoration of a posterior tooth received zirconia crowns (BruxZir shaded 200). Fifteen patients received subgingival featheredge finish line preparations (intervention group), and the other 15 patients received subgingival deep chamfer finish line preparations (comparator group). CAD/CAM milled zirconia crowns were cemented with resin cement. Position of crown margin (gingival recession) and marginal adaptation measurements were taken at baseline, 6 months, and 1 year. Results were tabulated, and statistical analysis was performed.
RESULTS: The results of gingival recession and marginal adaptation showed no significant difference between featheredge and deep chamfer designs at baseline, 6 months, and 1 year.
CONCLUSIONS: Monolithic zirconia crowns with subgingival restorative margin designs can be used with deep chamfer and featheredge margin designs, as both designs showed clinically acceptable results regarding gingival recession and marginal adaptation. Both margin designs behaved similarly after 1 year of clinical service, so special attention should be given to the position of the finish line and conservation in the choice of design.
CLINICAL SIGNIFICANCE: Both margin designs behave comparatively regarding gingival recession and marginal adaptation with zirconia crowns. To favor the more conservative approach that would preserve tooth structure, the featheredge margin design would be preferred, if not otherwise needed. The clinical trial was registered with the Clinical Trial Registry of clinicaltrials.gov (NCT04729569). How to cite this article: El-Khayat H, Anwar EM, Nabil O, et al. Gingival Recession and Marginal Adaptation of Zirconia Crowns with Two Subgingival Margin Designs: A Randomized Clinical Trial. J Contemp Dent Pract 2025;26(8):767-775.