Stress analysis of porcelain laminate veneer on lower central incisors with three-dimensional photoelastic experiments

Abstract

We performed stress analysis by the three-dimensional photoelastic experiments in order to elucidate dynamic behavior in porcelain laminate veneer restoration of the lower central incisors. We employed two models in preparing the crown: Model 1 (incisal edge not covered with laminate shell) and Model 2 (incisal edge covered with laminate shell).

We used two conditions of loading: Loading 1 (load applied to the labial mesial angle near the incisal edge from the side at an angle of 45° against the tooth axis) and Loading 2 (load applied to the incisal edge in parallel to the tooth axis).

• 1) Below the loading point during Loading 1 in Model 1 suggesting the possbility of laminate shell detachment.

• 2) In a wide range in the distal part of shell during Loading 1 in Model 2, suggesting the possibility of laminate shell detachment.

• 3) The results of our examination suggested that, in performing porcelain laminate veneer restoration in the lower central incisor, a more stable stress condition can be achieved when the abutment shape is used without reducting the incisal edge.