Fracture Load of Zirconia Crowns Based on Preparation and Cement Type
Abstract
Limited research has been published evaluating the failure of zirconia crowns with less retentive tooth preparations. The purpose of this study was to evaluate the effect of axial wall height (AWH) and cement type on the fracture load of cubic-containing zirconia crowns. Methods: Ninety extracted maxillary human third molar teeth were prepared with standardized crown preparations with AWHs of zero, two, or four millimeters (n=10). The preparations were scanned and crown restorations were designed (Omnicam, Dentsply/Sirona). Cubic-containing zirconia crowns (4Y-PSZ, Katana STML, Kuraray Noritake) were milled (MCXL, Dentply/Sirona) and cemented with either a resin-modified glass ionomer (RMGI) (RelyX Luting Plus, 3M/ESPE), a self adhesive resin (RelyX Unicem, 3M/ESPE), or an adhesive resin cement (Panavia V5, Kuraray). The specimens were subjected to thermocycling and cyclic loading. Each crown specimen was loaded to failure in a universal testing machine (Instron) at a 60-degree angle to the long axis of the tooth using a stainless-steel rod resting on the buccal incline of the palatal cusp. Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests (alpha=0.05). Results: Significant differences in fracture load were found between groups based on AWH and cement type (p<0.05). Regardless of cement type, the mean fracture loads were significantly lower for the zero millimeter AWHs than with 2-millimeter or 4-millimeter AWHs, which were not significantly different from each other. Compared to the other cement types, the adhesive resin cement provided a significantly greater fracture load with the zero-millimeter AWH. The use of an adhesive resin cement with a cubic-containing zirconia crown may provide greater fracture resistance with preparations having minimal axial wall height.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2021
- Accession Number
- AD1145384
Entities
People
- John S. Jenista
Organizations
- 59th Medical Wing