Fracture Resistance of Increasing Crown Heights on Prefabricated Titanium Abutments
Abstract
Purpose: Prefabricated titanium base inserts (Tibases) with a monolithic crown superstructure utilizing computer aided design and computer aided milling (CAD/CAM) have become a popular technique to restore dental implants. There is little information in the dental literature or from manufacturers regarding crown-to-Tibase height ratios. The aim of the present investigation was to determine the fracture resistance of monolithic zirconia CAD/CAM implant hybrid-abutment-crowns with increasing crown heights to determine a clinically relevant crown-to-Tibase height ratio recommendation. Material and Methods: Utilizing a 4mm Tibase height, three groups of zirconia monolithic implant hybrid abutment crown were fabricated with increasing crown heights of 6mm, 12mm, and 19.25mm to give respective crown-tibase height ratios of 1.5, 3, and 4.8. The samples were embedded in acrylic using a custom 3D printed resin holder to orient them at a 30 degrees off axis angle to the implant axis. The specimens were cyclic loaded for 250,000 cycles with a 50N force to simulate one year of chewing. Specimens were evaluated for cracking, chipping, or fractures. Reverse torque test was completed to account for screw or abutment loosening. All surviving specimens will then be subjected to a load to failure testing. The failure pattern for each specimen will be recorded. Results: All samples survived the 250,000 cycles of cyclic loading with no evidence of cracking, chipping, or fractures. Reverse torque testing showed all specimens maintained the original insertion torque value with no evidence of screw or abutment loosening. Load to failure testing will be completed for each specimen. Conclusions: Implant hybrid abutment crowns with crown-Tibase height ratios of up to 4.8 survived an estimated chewing simulation of one year. Load to failure testing will elucidate the biomechanical differences among the three test groups.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 08, 2022
- Accession Number
- AD1186243
Entities
People
- Scott D. Hopkins
Organizations
- Uniformed Services University of the Health Sciences