Effect of Cantilever Length on the Fracture Resistance of Full-Arch Implant-Supported Monolithic Zirconia Prostheses
Abstract
Purpose: The purpose of this study was to test the fracture resistance of screw-retained, implant-supported, monolithic zirconia prostheses with increasing distal cantilever lengths. Three different cantilever lengths based on different anterior-posterior (AP) spread to cantilever ratios were tested. Materials and Methods: Custom titanium jig was fabricated, and two 4.3 mm regular platform implant analogs (Nobel Biocare/Yorba Linda, CA) positioned and soldered onto the jig. Nobel multiunit scanbodies (Imagine/Virginia, USA) were placed on the implants and scanned with a laboratory optical scanner (Zirkonzahn/Gais, Italy). Half-arch monolithic zirconia prostheses of three different AP spread to cantilever ratios of 1:1, 1:1.5, and 1:2 were designed with Zirkonzahn software (Zirkonzahn/Gais, Italy). Thirty samples were milled and sintered in e.max ZirCAD LT zirconia (Ivoclar Vivadent/Amherst, NY) with ten prostheses per group. The prostheses were bonded to Nobel NMU multiunit ti-bases (Imagine/Virginia, USA) with Panavia 21 resin cement (Kuraray Dental/New York, NY). A universal testing machine (Instron/Norwood, MA) machine was then used to load the sample until any component of the restoration failed. The process was repeated for each of the sample. Results: The highest mean load to fracture was found in the 1:1 AP spread to cantilever ratio group at 698.51 +/- 72.387 N, followed by the 1:1.5 AP spread to cantilever ratio group at 423.48 +/- 92.389 N, and lastly by the 1:2 AP spread to cantilever ratio group at 268.32 +/- 31.733 N. The 275 N greater fracture load of the 1:1 group compared to the 1:1.5 group, and the 430 N greater fracture load of the 1:1 group compared to the 1:2 group, were statistically significant (p < 0.001). The 155 N greater fracture load of the 1:1.5 group compared to the 1:2 group was also statistically significant (p < 0.001).
Document Details
- Document Type
- Technical Report
- Publication Date
- May 30, 2022
- Accession Number
- AD1186204
Entities
People
- Han Eol Eom
- Walter G. Dimalanta