Effect of Surface Modifications on the Retention of Implant-supported Cement-retained Crowns with Short Abutments: An In Vitro Study.

Aim: The study aimed to evaluate and compare the effect of incorporating one circumferential groove and bur modification on retention of cast copings on implant abutment cemented with glass ionomer cement.
Materials and Methods: Fifteen straight shoulder implant abutments casted of height 6 mm used with corresponding 12 mm long stainless steel implant analog. The abutments were divided into three groups of five abutments in each group. Group I: Control group, without any surface modification, Group II: Milling of a circumferential groove, and Group III: Bur modification by creating punches of size whole round bur diameter 5 per axial surfaces. Glass ionomer definitive cement was used to adhere the cast copings to each group of abutments. After thermocycling, the specimens were evaluated for retention using the Instron Universal Testing Machine's pull-out test. The data were analyzed using One-way ANOVA, followed by the Tukey post-hoc test to compare the load among the three groups.
Results: According to the findings, the inclusion of a circumferential groove (Group II) increased the retention of glass ionomer cement maintained implant-supported crowns by 44.58%. The bur modification (Group III) boosted glass ionomer cement maintained implant-supported crown retention by 110.69% while retaining retrievability. Results were statistically significant.
Conclusion: Bur modification revealed more retention when compared to the groove and control group.
Clinical Significance: Short abutments are used in the clinical situation where interarch space is less. To achieve adequate retention of the implant crowns, surface modification of the abutments is necessary while selecting a cement-retained prosthesis.