Akademik Veri Yönetim Sistemi
European annals of dental sciences (Online), cilt.52, sa.2, ss.55-62, 2025 (TRDizin)
Purpose: The aim of this study was to evaluate the effect of two different crown and abutment types produced with CAD/CAM systems on the biomechanical behavior of implant-supported fixed restorations. Materials and Methods: Thirty-six titanium implants received either custom-made zirconia abutments cemented on a Ti-base (Zi) or single-piece custom titanium abutments (Ti). Then, resin-based ceramic crowns (RBC) were manufactured for half of each abutment type, and monolithic zirconia crowns (MZ) were manufactured for the other half. Thus, 4 study groups were formed as follows: Zi-RBC, Zi-MZ, Ti-RBC, and Ti-MZ. The fracture resistance of the groups was tested using a universal testing machine, and the failure types were determined. The stress distribution on abutments and crowns was evaluated with finite element analysis (FEA). Results: As the abutment type, zirconia showed higher fracture strength (1377.2 ± 185.7 N for Group Zi-RBC and 2333.9 ± 149.5 N for Group Zi-MZ) than titanium (1181 ± 119.6 for Group Ti-RBC and 1810.6 ± 315.2 for Group Ti-MZ) for both crown types. Considering the crown material, monolithic zirconia showed higher fracture strength for both abutment types. None of the groups showed screw or implant deformation. Ti-RBC and Ti-MZ groups showed only crown failures, while 22% of Group Zi-RBC and 44% of Group Zi-MZ showed abutment fractures in addition to crown fractures. FEA analysis did not show significant differences for crowns, while differences were observed for abutments. Conclusions: Zirconia abutments cemented on titanium bases can be considered an acceptable alternative to titanium abutments. Monolithic zirconia may provide longer intraoral service than resin-based ceramic as a crown material, considering its higher resistance to fracture.