Cone-Abutment Connection and Zirconia Restorations Influence on Peri-Implant Tissues Health

Objective: Stable crestal bone levels are believed to be critical for the long-term implant success. After implant insertion and loading, crestal bone usually remodels to a level about 2.0mm apical to the the implant–abutment junction in two-piece implants. This could be lead to a localized inflammation of the peri-implant tissues. The aim of this study was to evaluate the clinical outcomes of cone connection implants and zirconia restorations on peri-implant tissues.

Methods: 91 Morse cone connection implants (Ankylos® Dentsply Friadent, Mannheim, Germany) were inserted in 53 patients, ranging in age between 27 and 65 years old, to correct partial or single edentulisms. After an healing period of 2 months, the implants were loaded, for 1 month with resin provisional prosthesis and then with Zirconia core fixed partial dentures and were monitorized every 3 months for 2 years. The crestal bone height was evaluated with digital standardized radiographs; mSBI, mPlI, suppuration or gingival enlargment were recorded to study soft tissue conditions.

Results: Mean crestal bone loss at interproximal surfaces was ≤0,5 mm. Stable bone above the implant shoulder was detected in case of subcrestal positioning of the implant. No infrabony pockets were present. mPlI≤1 and mSBI≤1 were recorded regardless of patient smoking or hygene habits; no suppurations or gingival enlargments were observed.

Conclusions: It has been claimed that morse tapered abutment connection provides high resistance to micromotion and bacteria infiltration and that Zirconia provocs lower inflammatory level in surrounding tissues than titanium. Clinical outcomes seem to confirm reduced inflammatory manifestation of peri-implant soft and mineralized tissues using this kind of implant-prosthesis.