Fracture strength of various titanium-based, CAD-CAM and PFM implant crowns

J Esthet Restor Dent. 2021 Apr;33(3):522-530. doi: 10.1111/jerd.12672. Epub 2020 Nov 10.

Abstract

Objective: CAD-CAM has dramatically advanced dental restorative procedures to include implant-supported crowns. The purpose of this study was to compare the fracture resistance following mechanical loading and thermocycling of various screw-retained and cement-retained ceramic and polymethylmethacrylate material combinations using the TiBase abutment compared to PFM implant-supported crowns.

Overview: Twelve implant restorations were fabricated for each of eight groups. Three groups were screw-retained and five groups were cement-retained implant restorations. The ceramic and polymethylmethacrylate restorations were fabricated on the TiBase abutment while the PFM restorations were fabricated on an UCLA abutment. Data were analyzed with a one way Analysis of Variance and Tukey's post-hoc test to evaluate the effect of abutment and crown type on fracture load (alpha = 0.05). A significant difference was found in the maximum fracture load between groups (P < 0.001).

Conclusions: The screw-retained implant restorations demonstrated higher fracture loads than their cement-retained counterparts. The TiBase abutment compared favorably to the UCLA abutment.

Clinical significance: The TiBase abutment is a titanium insert which combines the esthetics of a ceramic abutment with the mechanical properties of a titanium abutment and should be considered a viable clinical alternative to the conventional implant-supported PFM crown based on theses in vitro results and in context of in vivo studies. The lithium disilicate hybrid abutment/crown implant-supported restoration utilizing the TiBase abutment may be an ideal clinical choice due to simplicity, single appointment CAD-CAM, and esthetics.

Keywords: CAD-CAM; TiBase; abutment; cement-retained; implant restoration; screw-retained.

MeSH terms

  • Computer-Aided Design
  • Crowns
  • Dental Abutments
  • Dental Implants*
  • Dental Porcelain
  • Dental Restoration Failure
  • Dental Stress Analysis
  • Flexural Strength
  • Materials Testing
  • Titanium*
  • Zirconium

Substances

  • Dental Implants
  • Dental Porcelain
  • Zirconium
  • Titanium