Rigenerazione ossea tridimensionale mediante Membrane in D-PTFE rinforzate in titanio o griglie in titanio, in associazione ad impianti conici a doppia spira variabile. Studio randomizzato controllato.

PURPOSE: The aim of this randomized clinical trial is to compare 2 different approaches for Guided Bone Regeneneration (GBR) in posterior region of atrophic mandibles regarding: I) the amount of vertical bone regeneration, II) the type and frequencies of surgical and healing complications, III) the implants primary stability and the osseointegration rate. MATERIAL AND METHODS: Forty partially edentulous patients with atrophic posterior mandible, who require a three-dimensional bone regeneration and an implant-prosthetic rehabilitation, were treated according the following protocol. Patients were randomly divided into two study group: 20 patients were treated with non-resorbable d-PTFE titanium-reinforced membranes (group A); and 20 patients with titanium mesh covered by cross-linked collagen membranes (group B). All patients received two or more double variable thread tapered implants and a mixture of autogenous bone and bone allograft according to one-stage GBR approach. In each group were evaluated the amount of vertical bone regeneration and the insertion torque value (IT) and implant stability quotient (ISQ) of all implants. In addition, all complications were analyzed, distinguishing between “surgical” and “healing” complications. RESULTS: The vertical bone regeneration was 4.3 ± 1.2 mm in the group A and 4.2 ± 1.1 in the group B. 99% of implants showed an optimal primary stability with insertion torque values > 35 Ncm and ISQ values > 60. All implants achieved a successful osseointegration. In the group A, surgical and healing complication rates were 5.0% and 15.9% respectively, In the group B, complication rates were 15.0% and 21.1% respectively. CONCLUSIONS: The preliminary results of this RCT suggested that both GBR approaches are predictability and effectiveness for the restoration of atrophic posterior mandible. Double variable thread tapered implants permitted to achieve an adequate primary stability in order to perform an one-stage GBR approach.