Purpose: To provide a 1-year assessment of friction-retention abutments used to retain a single lithium disilicate (LS2) monolithic restoration.
Materials and Methods: A total of 522 implants were placed to treat a mandibular or a maxillary single-tooth premolar or molar edentulous site. Three types of implants were used. The tested abutments were connected 3 months after implant placement. A single pressed LS2 monolithic restoration was cemented to a dedicated titanium cap and engaged to the abutment without the use of screws or cement. Any complications affecting the restoration or the opposing dentition, any soft tissue dimensional changes, the distance between the implant platform and the bone peak, and pocket probing depths were recorded at the time of restoration placement (T0), after 6 months of function (T1), and after 1 year of function (T2). Esthetic, functional, and biologic parameters were recorded at T0 and T2.
Results: A total of 507 patients (284 women and 223 men) received a restoration at T0, and 504 reached the 1-year follow-up at T2. One restoration fractured after 10 months in function. No statistically significant differences were seen in the soft tissue measurements or in the measurements of the distance between the supporting implant platform and the bone peak. None of the restorations detached during the observation period.
Conclusion: The friction retention abutment is a viable option to retain an implantsupported monolithic LS2 glass-ceramic restoration in cases of premolar or molar single-tooth edentulism.
