Comparison of Excess Cement around Cement-Retained Implant Restorations between two Extra-Oral Cementation Methods and Conventional Intra-Oral Cementation Technique

Cementation for attaching crowns to implants has found wider use due to various reasons, including clinical advantages and aesthetic preservation. However, cement-retained prostheses have drawbacks such as the possibility of excess cement and its leakage into the surrounding tissues of the implant, which can lead to inflammatory complications in these tissues. The use of the extra-oral cementation technique can minimize excess cement. Accordingly, in this laboratory study, two extra-oral methods, PIA (Putty Index Analogue) and LBA (Light Body Analogue), and the conventional intra-oral cementation method were compared in terms of the amount of excess cement leakage when placing a crown on an implant model.

In this laboratory study, 30 zirconia frameworks were fabricated on three abutment-analogue sets for three study groups. The control group underwent the conventional intra-oral cementation method. The LBA group used a light body condensation silicone. The PIA group used a silicone putty for cementation. In each group, after cementation, the excess cement around the abutment-crown connection was manually removed using a dental scaler and weighed with a digital scale with an accuracy of ±0.01 mg.

The excess cement in the control group was reported as 85.23 ± 13.07 mg, in the LBA group as 1.70 ± 0.55 mg, and in the PTA group as 7.11 ± 1.45 mg. The average excess cement in the LBA and PTA groups was significantly lower than in the control group (both groups with p value < 0.001). However, the difference in average excess cement between the LBA and PTA groups was not statistically significant (p value = 0.265).

The extra-oral cementation techniques, PIA and LBA, significantly reduced the amount of excess cement compared to the conventional technique in implant-based restorations, which may limit the adverse effects of excess cement on surrounding tissues..