A 3-year clinical evaluation of endocrown restorations with two different materials using the computer-aided design/ computer-aided manufacture system

Objective: To compare the clinical efficacy of resin nanoceramic and zirconia-reinforced lithium silicate ceramic endocrowns in the treatment of endodontically treated teeth by assessing the clinical performance of restorations fabricated using a chairside computer-aided design/computer-aided manufacturing (CAD/CAM) system. Materials and methods: Ninety endocrown restorations were fabricated on endodontically treated teeth using a CAD/CAM system. Fifty-two restorations were fabricated using Lava Ultimate blocks (LU, 3 M Espe, Seefeld, Germany) and 38 restorations were fabricated using Celtra Duo blocks (CD, Dentsply Sirona, York, PA, USA). The performance of the endocrown restorations was evaluated over a 3-year period using the modified United States Public Health Service (USPHS) criteria by two calibrated evaluators. The data were analyzed using Chi-square (x(2)) and Fisher exact tests (p < 0.05). Results: The restoration survival rates in the two groups were 82.7 % (LU) and 86.8 % (CD) (p = 0.6). Twelve restorations failed (8 LU, 4 CD) due to debonding (n = 4, 2 LU, 2 CD), ceramic fracture (n = 2, 1 LU, 1 CD), tooth fracture (n = 5, 4 LU, 1 CD), and secondary caries (n = 1, 1 LU) during the follow-up period. There was no statistically significant difference between the two materials according to the modified USPHS criteria (p > 0.05). Conclusion: Resin nanoceramic and zirconia-reinforced lithium silicate ceramic endocrown restorations fabricated using a chairside CAD/CAM system demonstrated acceptable clinical performance in the treatment of endodontically treated teeth. Clinical Significance: Resin nanoceramic and zirconia-reinforced lithium silicate ceramics are potential alternative materials for the chairside fabrication of endodontically treated teeth.