Internal fit evaluation of indirect restorations fabricated from CAD/CAM composite blocks versus ceramic blocks in badly broken teeth using cone beam CT (CBCT): double-blinded randomized clinical trial

OBJECTIVE: The restoration durability is essentially governed by optimum marginal integrity of an indirect restoration that is obtained and maintained by essential factors. This study aimed to evaluate the internal gap of indirect restorations fabricated from CAD/CAM composite blocks versus ceramic blocks in badly broken teeth using cone beam CT (CBCT) to determine their internal fit accuracy over the cast. MATERIALS AND METHODS: Fifty-four participants were allocated into two groups: composite blocks or ceramic blocks. The trial participants and assessors were blinded to the material assignment, whereas the operator was not. Cavity preparation was performed followed by cavity optimization and impression taking. The produced master cast was scanned, restoration was designed using Exocad 2019 software and the final restoration was milled. The restoration was doubled-checked on the cast for internal fit using cone beam computed tomography (CBCT), and intraorally for interproximal contact and marginal adaptation before final cementation. CBCT measurements were collected and statistically analyzed. Restoration was cemented with resin cement and was immediately assessed clinically, then after one year and two years of follow-up periods. RESULTS: Results of an independent t-test revealed Composite blocks samples (0.25mm ± 0.03) to have a significantly better adaptation than ceramic blocks samples (0.29 mm ± 0.04) (p = 0.008). CONCLUSIONS: Both materials have acceptable internal adaptation with a noticed difference reflected in their clinical performance. CLINICAL RELEVANCE: Both indirect esthetic CAD/CAM restorations exhibit acceptable internal and marginal adaptation in posterior teeth however, composite blocks have a better adaptation than ceramic blocks. TRIAL REGISTRATION: This trial was registered in clinicaltrials.gov (NCT04784676).