Evaluation of Effect of Screw Access Filling Materials on the Retention of Cement-Retained Implant Supported Crowns with Surface Modified Abutments – An In Vitro Study

Abstract

Background Inadequate data regarding advantages of screw access filling materials and its interaction with the luting agent for improving retention in clinical scenarios with minimal abutment height.Objectives To evaluate the effect of three different screw access filling materials on the retention of cement-retained implant supported crowns with sandblasted abutments when zinc phosphate is used as the luting agent.Methods Thirty Bioline straight dental implant abutments sandblasted and reduced to a height of 5 mm were attached to their corresponding analogs. Thirty Direct Metal Laser Sintering DMLS copings were fabricated. The samples were divided into three groups of ten each and filled with three different screw access filling materials Group A ndash Composite Resin Group B - Cavit and Group C ndash Teflon Tape. All the copings were cemented with zinc phosphate and stored in artificial saliva for 14 days at 37degC. Tensile testing was done in a universal testing machine at a cross-head speed of 5 mmmin. The data collected was subjected to One-way ANOVA test to determine the difference between groups.Results Although the mean uniaxial retentive force was found to be highest for Group B 804 N followed by Group A 690 N and Group C 668 N the results of the One-way ANOVA test showed no statistically significant difference in uniaxial retentive force between the three groups.Conclusion The retention of cement-retained implant supported crowns may not be affected by the screw access filling materials when zinc phosphate is used as the luting agent on sandblasted abutments.