Fracture Rates and Lifetime Estimations of CAD/CAM All-ceramic Restorations

Abstract

The gathering of clinical data on fractures of dental restorations through prospective clinical trials is a labor-and time-consuming enterprise. Here, we propose an unconventional approach for collecting large datasets, from which clinical information on indirect restorations can be retrospectively analyzed. The authors accessed the database of an industry-scale machining center in Germany and obtained information on 34,911 computer-aided design (CAD)/computer-aided manufacturing (CAM) all-ceramic posterior restorations. The fractures of bridges, crowns, onlays, and inlays fabricated from different all-ceramic systems over a period of 3.5 y were reported by dentists and entered in the database. Survival analyses and estimations of future life revealed differences in performance among ZrO 2 -based restorations and lithium disilicate and leucite-reinforced glass-ceramics.

ADM guidance-Ceramics: all-ceramic multilayer interfaces in dentistry

“…A prospective clinical trial on multilayer Cad-On ® and monolithic lithium disilicate molar crowns showed no technical failures or fractures after 2 years in service [111]. Another statistical survival analysis based on a large dataset from a CAD/CAM milling center showed 8% fractures of zirconia veneered and glass-fused multilayer FPDs over an interval of 3.5 years [112]. However, in the referred study, the glass-fused multilayer was processed differently from what is recommended by Ivoclar for the CAD-On ® technique, as the milling center used a different fusion glass as well as no vibration to assist accommodation of the fusion glass.…”

Longevity of ceramic onlays: A systematic review

“…The clinical studies have confirmed the successful use of ceramics as dental restorative materials . However, due to the considerable variation, it can be challenging to compare outcomes between studies, materials and restoration types.…”

Fracture Resistance of CAD/CAM‐Fabricated Lithium Disilicate MOD Inlays and Onlays with Various Cavity Preparation Designs

“…In the stress‐bearing areas, the preparation design to allow 2‐mm material thickness for the ceramic indirect restoration is essential to resist flexure under loading . Moreover, the lithium disilicate restorations showed better clinical performance than the leucite‐based glass‐ceramic restorations, emphasizing the importance of the microstructure in the fracture resistance . A previous in vitro study using a lithium disilicate ceramic reported that a reduction of 25% to 50% of the standard preparation depth (2 mm) did not impair fracture resistance of the onlay restoration on premolars …”