Clinical Efficacy and Long-term Observation of Fiber Post-and-Core Crown versus Onlay Restoration for Posterior Teeth with Post-endodontic Defects.

This retrospective study aimed to compare the clinical efficacy and long-term outcomes of fiber post-and-core crown restoration and all-ceramic onlay restoration for posterior teeth with defects following root canal treatment. A total of 100 patients treated between January 2020 and December 2022 were allocated to two groups (n = 50 each): a fiber post-and-core crown group and an all-ceramic onlay group. Restoration integrity, tooth integrity, marginal adaptation, interproximal contacts, periodontal parameters (periodontal pocket depth, gingival index, and plaque index), masticatory function (bite force and chewing efficiency), and oral health-related quality of life (OHIP-14 scores) were evaluated before treatment and at 3 months and 2 years after restoration. No significant differences were observed between the groups in restoration integrity, tooth integrity, marginal adaptation, or interproximal contacts at either follow-up. However, the all-ceramic onlay group demonstrated significantly lower periodontal pocket depth, gingival index, and plaque index at both follow-up time points. Bite force and chewing efficiency were significantly greater in the onlay group, and OHIP-14 scores indicated better oral health-related quality of life. At the 2-year follow-up, two restoration failures occurred in the fiber post-and-core crown group, whereas no failures were observed in the all-ceramic onlay group. These findings suggest that all-ceramic onlay restorations provide superior clinical outcomes for posterior teeth after root canal treatment, particularly with respect to periodontal health, masticatory function, and patient-reported quality of life, and may represent a promising alternative to conventional fiber post-and-core crown restorations.