Influence of CAD/CAM materials on damping behavior of implant-supported crown

Abstract

This study was to investigate the damping capacity of implant-supported crowns made from various computer-aided design and computer-aided manufacturing (CAD-CAM) restorative materials. A titanium implant fixture was embedded in epoxy resin. Crown specimens were divided into three groups: Zirconia (Z), Lithium disilicate (E), and Polymethyl methacrylate (P). Each crown was subdivided into Uncement (Un) and Adhesive resin cement (RC) subgroups (n=5). Specimens were loaded (0-200N). Strain gauges were attached to measure microstrains at crestal and apical levels. Damping capacity was determined based on load-time curves, microstrain-time curves, and time required to reach the maximum load. A two-way ANOVA with Tukey post hoc test and independent t-test were conducted (α=0.05). The results showed that slopes of curves and time to reach maximum load were similar in the Z and E groups (p>0.05), but the P group exhibited less steep slopes and more time to reach maximum load (p<0.05). The UN group had significantly steeper microstrain slopes at crestal level and less time to reach maximum load compared to the AR group (p<0.05). In conclusion, the crown material significantly influenced the damping capacity, with lower modulus of elasticity materials showing higher damping capacity. Cementation enhanced damping capacity in implant-supported crowns.