Autogenous bone block grafting provides facial implant tissue stability long-term

Abstract

Background: Mucosal recession (MR) and bone loss can compromise anterior implant esthetics.

Purpose: To evaluate tissue stability and clinical outcomes of anterior implants augmented with autogenous block transplants long-term.

Materials and methods: This prospective cross-sectional clinical study analyzed facial tissue recession of anterior implants augmented with autogenous bone blocks and compared them to adjacent teeth in forty patients 52 months post-augmentation. Clinical parameters, MR and implant transparency, were assessed at delivery and follow-up. The hypothesis is that the facial mucosa of augmented implant sites is more resistant to trauma than the gingival margins of adjacent teeth.

Results: Teeth were seven times more likely to present a facial recession than adjacent augmented implants at 52-month follow-up (RR: 7; P < .001; 95%CI: 2.7-18.0). Augmented implant sites were six times more likely to present "no-tissue-recession" than adjacent teeth (RR: 6.2; P < .001; 95%CI: 2.4-15.7). Mean tooth facial tissue recession was significantly higher than adjacent implants, 1.18 ± 1.05 mm (range: 0-3.5 mm) vs. 0.06 ± 0.2 mm (95%CI: 0.8-1.5; P < .0001). Thick biotype teeth were 2 times more resistant to recession than thin biotype teeth (RR: 2.03; P = .03; 95%CI: 1.2-3.5). Implant success rates were 100%. Lack of transparency and MR at facial implant sites lasted an average of 52 months and up to 144 without signs of inflammation or pocket formation regardless of the individual's biotype. Facial bone thicknesses of 2.2 mm seem optimal for tissue stability.

Conclusions: Autogenous bone block augmentation with staged implant placement seems to be a predictable, short-healing, reconstructive protocol in the esthetic zone maintaining stable peri-implant tissues long-term. Implant augmented sites seem more resistant to develop a recession than adjacent teeth.

Keywords: bone graft; bone regeneration; bone transplant; endosseous implants; gingival recession; periodontal attachment loss; ridge augmentation.