Rigidity and retention of ceramic root canal posts

Ceramic root-canal posts offer potential advantages over other types with r espect to aesthetics and biocompatibility. Any post must be sufficiently ri gid and retentive to withstand functional forces. Ceraposts (1.2 mm coronal diameter, ceramic, tapering, smooth posts) and Paraposts (1.25 mm, stainle ss-steel, parallel, serrated posts) were tested for rigidity by means of a three-point bending test. To test retention in roots, ceramic posts were ce mented using one of three protocols: (1) glass-ionomer cement, (2) silane c oupling agent and resin cement, or (3) sandblasted post surface, silane cou pling agent, and resin cement. Stainless-steel posts were cemented with res in. The tensile force required to dislodge the posts, following four weeks of storage in water, was recorded. Data were compared using Student's t-tes t and Mann-Whitney U analysis. Ceraposts were significantly more rigid than Paraposts (p<0.001). Paraposts cemented with resin were significantly more strongly retained than Ceraposts following any cementation protocol (p<0.0 01). Retention of the ceramic posts was significantly greater with a silane coupling agent and resin cement than with glass-ionomer cement (p<0.001). Sandblasting the ceramic posts produced variable results and needs further investigation before it could be recommended.