Abstract
Introduction:
Ceramic veneers are considered one of the most essential demands in dental aesthetics. It provides high accuracy and efficiency in restoring tooth shape, shade, form, and function. Preparation design is considered a critical factor in the success of dental veneers, as it influences the failure load and fatigue survival of posterior minimally invasive ceramic veneer restorations.
Objective
To assess how various preparation designs affect the minimally invasive posterior ceramic veneer restorations' fatigue survival and failure load.
Materials and methods
64 human premolars were divided into four groups of equal size. Group 1 had a buccal preparation depth of 0.7 mm; group 2 had an additional reduction of the buccal cusp, group 3 had a mesio-occluso distal box. The occlusal box preparation has a vertical dimension of three mm and a horizontal dimension of 2 mm, while sound teeth serve as control. Monolithic lithium disilicate restorations were cemented in adhesive cement and then exposed to dynamic fatigue while thermocycling. Each specimen underwent a single load-to-failure test, and the discrepancy in failure load before and after fatigue was computed.
Results
no significant differences in initial fracture resistance were observed among the four groups evaluated (p < .075). Nevertheless, after fatigue, significant differences were detected (p < .013) as fatigue caused a substantial drop in fracture resistance among all groups.
Conclusion
Within the limitations of this study, minimally invasive preparation designs are recommended compared to full coverage aggressive preparation designs.