The effects of post and core material combination on the surface strain of the 4-unit zirconia fixed partial denture margins.

The suitability of various post and core materials for the 4-unit zirconia fixed partial denture abutment teeth was investigated to lower stress concentration. Artificial mandibular teeth (44 and 47) were used as the abutment teeth. There were two types of posts and cores: resin composite with glass fiber posts (RC), and cast platinum gold alloy (MC). Two experimental groups were analyzed. For Group RM, the premolars were restored with RC and the molars were restored with MC. For Group MR, the premolars were restored with MC and the molars were restored with RC. Static loading was applied to the occlusal surfaces, and the surface strain of the frameworks and roots was measured with a strain gauge. Group RM had a greater number of statistical differences between premolars and molars compared to Group MR. This result suggests that the Group MR post and core material combination reduces stress concentration.