The influence of CADCAM ceramic and heat processed composite inlays on the fracture resistance of premolars : an in-vitro study

Abstract EN

Background : The aim of this in-vitro study was to identify the influence of intracoronal indirect adhesive techniques (heat processed composite (SR Adoro) andcomputer-aided design / computer-assisted manufacturing (CAD / CAM) ceramic (e Max CAD) inlays)on the fracture resistance of maxillary first premolars and to identify the modes of fracture of all experimental groups. Materials and Methods : Forty sound freshly extracted upper first premolar teeth were selected then mounted in acrylic blocks, the teeth were divided into four groupsas follow : Group (A) : tenintact teeth (control group).

Group (B) : ten teeth prepared with standardized MOD inlay cavity but not restored.

Group(C) : ten teeth prepared with standardized MOD inlay cavity and restored with indirect heat processed composite (SR Adoro).Group (D) : ten teeth prepared with standardized MOD inlay cavity and restored with CAD / CAM ceramic material (e max CAD).

Fracture strength of the experimented teeth was measured by using universal testing machine (an axial compression test).

Data were analyzed statistically by ANOVA and least significant difference tests. Results : Group (D) restored with CAD / CAM ceramic inlays showed more resistance to fracture than teeth restored with SR Adoro composite inlays group (C), but the values are statistically not significant, using One way ANOVA test a highly significant differences (P < 0.01) were found among all groups. Conclusions : All CAD / CAM ceramic inlays and 80 % of heat processed compositeinlays survived maximum biting force for posterior single tooth, so these two types of inlays provide good reinforcement in an extensive MOD cavities in premolars, The fracture Mode of SR Adoro composite inlays seems to be 80 % restorable while CAD / CAM ceramic inlays 90 % of it are restorable type of fracture.