Evaluation of tensile strength of different esthetic coping materials to Ti-base and monolithic zirconia crowns

This study evaluated the tensile strength of three aesthetic abutment materials at two different angulations (0 and 15°) to Ti-base and monolithic zirconia crowns. Prefabricated polyvinylidene difluoride (Medentika Implant) abutments were obtained and zirconia (Kingch) and polyetheretherketone (Ceramill) copings were manufactured using a computer-aided design/computer-aided manufacturing system (n = 12). Bonding surfaces of the copings and Ti-bases were air-abraded with alumina and then metal primer was applied. Self-adhesive resin cement (Multilink Hybrid Abutment) was used for cementation of copings to Ti-base. The bonding surfaces of the monolithic zirconia crowns (Upcera ST ML) were air-abraded and crowns were cemented using self-adhesive cement (seT PP). Data were analyzed using Kruskal–Wallis and Mann–Whitney U tests. No significant difference was found in the tensile strength of abutment to the crown interface for 0° tapered abutments (p > 0.05). Regarding 15° tapered abutments, the highest tensile strength values were obtained with zirconia abutments (p < 0.05). The tensile strength of monolithic zirconia crowns was lower than the restorations used in routine clinical practice.