The Influence of Different Pontic Designs on Fracture Resistance of Implant-supported Fixed Partial Dentures Anchored in Polyurethane Simulating Bone-blocks of Two Different Densities: An In Vitro Study.

Aim: This study aimed to evaluate the fracture resistance of implant-supported fixed partial prostheses fabricated from monolithic zirconia with different pontic framework designs and anchored in different bone-like simulation models of two different densities.

Materials and methods: A total of 60 implants were anchored in two different in vitro bone simulation models of two different densities, namely, solid polyurethane foam blocks, 20 and 10 pounds per cubic foot (PCF) to construct implant-supported fixed partial dentures (FPDs), the pontic constructed to replace missing second premolar and first molar. Thirty models were constructed and then divided into two groups according to anchoring material D2 (n = 15) and D3 (n = 15). Each group of models was subdivided into three groups according to pontic design (n = 5). Each model was tested against fracture in a universal testing machine. The data were analyzed with a two-way univariate ANOVA and Tukey HSD test (α = 0.05). The results were statistically analyzed, and the values were considered significant at p≤0.05.

Results: The findings showed that neither change in pontic design nor change in bone type has a significant influence on the fracture resistance of the prostheses (p > 0.05). All the tested materials fell within the acceptable range for functioning under mastication, with a slight change in resistance when the pontic design was changed.

Conclusion: Zirconia is considered the material of choice when planning implant-supported FPDs because of its high fracture strength values. Within the limitations of this study, the pontic design and synthetic polyurethane bone-simulating model had no effect on the fracture resistance of four-unit implant-supported FPDs.

Clinical significance: This study postulated that any pontic design could be used in four units of implant-supported FPDs according to functional and aesthetic needs, as long as the histological nature of the alveolar bone falls within the D2 or D3 bone type. How to cite this article: Othman MS, Abu-Eittah MRH. The Influence of Different Pontic Designs on Fracture Resistance of Implant-supported Fixed Partial Dentures Anchored in Polyurethane Simulating Bone-blocks of Two Different Densities: An In Vitro Study. J Contemp Dent Pract 2024;25(7):684-690.