Evaluation of post retention using different cementing techniques

Objectives: The objective of this study was to evaluate in vitro the retention of intraradicular posts varying the application technique of the adhesive and resin cement in the prosthetic space. The crowns of sixty endodontically treated maxillary canines were discarded and the roots included in acrylic resin. Methods: The prosthetic spaces were prepared with a largo bur activated with a micromotor attached to a parallelometer in order to maintain the length and diameter of the intraradicular posts constant. After casting, the posts were randomly divided into 3 groups according to the application technique of the cement: G1 with a post, G2 with a lentulo bur and in G3 the association of both. Each group was then divided into 3 subgroups according to the application technique of the adhesive: with a microbrush or with a brush. Seventy-two h after cementing, the posts were tractioned at a velocity of 1 mm/min by a universal testing machine (Instron 4444). Results: There was a statistically significant difference (p<0.01) between application techniques of the adhesive. However, regarding the application technique of the cement in the interior of the root canal, the cement placed with the post was statistically different from the other two methods (p<0.01). Conclusions: We conclude that the application techniques of the adhesive with the microbrush had the best results and that the cement placed into the prosthetic space before the placement of the post favored its retention.