Clinical Performance of One-Piece Molar Endocrowns Fabricated from Different Ceramic Materials: A 36-Month Retrospective Clinical Study.

Abstract

Background: This retrospective observational clinical study designed to assess the clinical performance and outcomes of cemented one-piece molar endocrowns (ECs) using the United States Public Health Service (USPHS) criteria at various time intervals. Additionally, patient satisfaction for cemented ECs was measured using the Visual Analog Scale (VAS).

Methods: Clinical data were collected from 29 participants (mean age 26.34 ± 6.99 years) who received ECs at a specialist dental center. Twenty-four ECs were constructed from lithium disilicate glass-ceramic (LDGC) and five from multilayered zirconia. All patients were analyzed at each follow-up (baseline, 6, 12, 24, and 36 months). Clinical performance was evaluated using modified USPHS criteria, and patient satisfaction was measured with a VAS. Statistical analyses included ANOVA and McNemar tests, with significance set at p ≤ 0.05.

Results: After 36 months most LDGC restorations retained "Alpha" (clinically excellent) scores for marginal adaptation, color match, anatomical form, restoration integrity and retention; zirconia restorations showed a mix of Alpha and Bravo scores. Significant differences between the materials were found for color at baseline (p=0.001) and at 36 months (p=0.018) and for retention at 36 months (p=0.001). Overall patient satisfaction by VAS remained high across groups.

Conclusion: Despite the limitations of a small zirconia sample, LDGC ECs showed better color matching and retention than zirconia. Zirconia is still a viable option where strength is essential. Material selection should consider esthetic demands and occlusal load. Long-term studies with larger cohorts are needed for validation.