Lateral ridge augmentation using different bone fillers and barrier membrane application - A histologic and histomorphometric pilot study in the canine mandible

Lateral ridge augmentation has become a standard treatment option to enhanc e the bone volume of deficient recipient sites prior to implant placement. In order to avoid harvesting an autograft and thereby eliminating additiona l surgical procedures and risks, bone grafting materials and substitutes ar e alternative filler materials to be used for ridge augmentation. Before cl inical recommendations can be made, such materials must be extensively stud ied in experimental models simulating relevant clinical situations. The pre sent pilot study was conducted in three dogs. Different grafting procedures were evaluated for augmentation of lateral, extended (8x10x14 mm) and chro nic bone defects in the mandibular alveolar ridge. Experimental sites recei ved tricalcium phosphate (TCP) granules or demineralized freeze-dried hone allograft (DFDBA) particles. Barrier membranes (ePTFE) were placed for graf t protection. These approaches were compared to ridge augmentation using au togenous corticocancellous block grafts, either with or without ePTFE-membr ane application. After a healing period of six months, the sites were analy zed histologically and histomorphometrically. Autografted sites with membra ne protection showed excellent healing results with a well-preserved ridge profile, whereas non-protected block grafts underwent bucco-crestal resorpt ion, clearly limiting the treatment outcome. The tested alloplastic (TCP) a nd allogenic (DFDBA) filler materials presented inconsistent findings with sometimes encapsulation of particles in connective tissue, thereby reducing the crestal bone width. The present pilot study supports the use of autogr afts with barrier membranes for lateral ridge augmentation of extended alve olar bone defects.