Effect of Cement Type and Cementation Technique on the Retention of Implant-Supported Restorations.

OBJECTIVES: This study aimed to assess the effect of cement type and cementation technique on the retention of cement-retained implant-supported restorations. MATERIAL AND METHODS: In this in vitro study, 20 solid abutments were screwed onto the fixture analogs and were mounted in acrylic resin molds using a surveyor. Twenty computer-aided design/computer-aided manufacturing (CAD/CAM) metal crowns with an occlusal loop were fabricated, divided into two groups (n = 10), and bonded with temporary dental cement (Temp-Bond; group 1) or glass ionomer (GC; group 2). Each group was subcategorized based on its cementation method (half-filling or abutment replica technique). The cement was applied to the copings that were placed vertically on the abutment with applying a 5-kg load for 10 min. The samples were then incubated at 37 degrees C for 24 h and subjected to 3000 thermal cycles. The samples underwent axial tensile load within a universal testing machine. Data were analyzed using two-way ANOVA. RESULTS: GC cement yielded significantly higher retention than Temp-Bond (P < 0.05). In the GC group, the half-filling subgroup showed significantly higher retention than the abutment replica subgroup (P < 0.05). The mean retention value in the Temp-Bond group revealed no significant difference between the two subgroups (P > 0.05). GC yielded higher retention than Temp-Bond while using the half-filling cementation technique (P = 0.00). However, this difference was not significant between GC and Temp-Bond with the abutment replica technique (P = 0.960). CONCLUSION: Within the limitations of this study, the results showed that permanent cementation with half-filling technique yielded significantly higher retention in implant restorations.