Effect of collagen membrane and of bone substitute on lateral bone augmentation with titanium mesh: An experimental in vivo study

Aim: The aim of this study was to identify the additional effects of collagen membrane (CM) and of synthetic bone substitute (BS) on lateral bone augmentation of chronic peri-implant defect with titanium mesh (TM). Materials and Methods: Atrophic alveolar ridge was induced in six canine mandibles, and 5 peri-implant defects were achieved in each hemi-mandible. Bone augmentation was attempted using the following randomly allocated modalities: (1) Control: no treatment, (2) TM only group: blood clot covered by TM, (3) TM+BS group: BS covered by TM, (4) TM+CM group: blood clot covered by TM and CM, and (5) TM+BS+CM group: BS covered by TM and CM. After 16 weeks of submerged healing, micro-CT and histomorphometric analyses were performed. Results: TM exposure occurred in one case in the TM only group, one case in the TM+CM group, and two cases in the TM+BS+CM group. Histologically, pseudo-periosteum was observed along the inner and outer surfaces of TM, and the directions of the collagen fiber within the pseudo-periosteum differed according to the additional use of CM. In general, the TM only group rendered higher values in vertical defect fill and dimension of the augmented hard tissue in comparison with the other treatment groups. Conclusions: Due to the small sample size, this pilot study remains inconclusive. Within the limitations of the study, the use of CM and/or BS did not appear to have an additional benefit on lateral bone augmentation of peri-implant defect with TM.