Abstract
Background: The purpose was to compare the fracture resistance and the mode of failure of different contemporary restorative materials to restore implant supported, cement-retained mandibular molars. Methods: Two 5 × 10 mm titanium dental implants were mounted in resin blocks and prefabricated titanium and zirconia abutments were connected to each implant. Each implant received forty crowns resembling mandibular first molars. The specimens were divided into four groups (n = 10/group) for each abutment according to the type of material; Group A: porcelain fused to metal crowns; Group B: monolithic zirconia crowns; Group C: zirconia coping with ceramic veneer; Group D: all ceramic lithium disilicate crowns. Specimens were cemented to the abutments, mounted into a universal testing machine, and vertical static load was applied at a speed of 1 mm/min. The test stopped at signs of visual/audible fracture/chipping. Fracture resistance values were analyzed using ANOVA and Tukey’s tests (α ≤ 0.05). The modes of failure were visually observed. Results: A statistically significant difference (p < 0.001) of the fracture resistance values among tested groups was found. The group that showed the highest fracture resistance was Group A for both the titanium and the zirconia abutments (3.029 + 0.248 and 2.59 ± 0.39, respectively) while Group D for both abutments (1.134 + 0.289 and 1.68 ± 0.13) exhibited the least resistance. Conclusions: Fracture resistance and fracture mode varied depending on type of restorative material. For both titanium and zirconia abutments, porcelain fused to metal showed the highest fracture resistance values followed by monolithic zirconia.
Highlights
Introduction iationsDuring the last few decades, osseointegrated dental implants have become an essential part of dental treatment for edentulous and partially edentulous patients
The fracture resistance and mode of failure of common restorative materials used for implant-retained mandibular molars cemented over titanium and zirconia abutments were evaluated and compared
The highest (3.029 ± 0.248 mega pascals (MPa)) and lowest (1.134 ± 0.289 MPa) mean values for the load (MPa) needed to fracture the crowns cemented over the titanium abutment were determined for Group A and Group D
Summary
During the last few decades, osseointegrated dental implants have become an essential part of dental treatment for edentulous and partially edentulous patients. This treatment modality resulted in a dramatic improvement in the quality of life of these patients [1–3]. Single implant-retained restorations are known to have several advantages, both aesthetically and functionally [7]. These advantages include, but are not limited to, the reduction of bone resorption around the implant, the preservation of sound adjacent teeth, and better access to oral hygiene between the implant crown and adjacent natural teeth [7,8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
