Comparison of two pre-prosthetic surgical techniques for augmentation of mandibular vertical ridge defects

Aim To compare two pre-prosthetic surgical techniques for augmentation of vertical mandibular ridge defects in view of implant placement. 

Materials and methods A prospective controlled clinical trial was conducted on 14 patients, having about 7 mm of vertical bone height in the posterior mandible above the inferior alveolar canal. They were then divided into 2 groups of 7 patients each. The first group received customized ceramic membranes with a vertical height 5 mm above the crest of the ridge to tent out the soft tissue matrix, while in the second group, tenting of the soft tissue was done by fixation of two tenting screws, particulate bone graft was packed then covered by collagen membrane that was fixed by bone tacks (modified sausage technique).

Results Three cases out of seven (42.9%) have been detected with wound dehiscence in group 1 during the second week after surgery. Two cases out of seven (28.6%) in group 2 have shown wound dehiscence in the first week. Radiographic examination has shown a mean preoperative bone height of 7.146 ± 0.24 mm from the crest of the ridge to the inferior alveolar nerve. The mean postoperative bone height after 6 months was 10.266 ± 0.97 mm. The mean percentage of change of bone height in group 1 was 52.8204 ± 8.7672 %, while the mean percentage of change of bone height in group 2 was 34.4978 ± 9.1760 %. The difference between the two groups was statistically significant (p=0.002) in favor of the ceramic membrane group. 

Conclusion Both methods of GBR either by using customized ceramic membranes or modified sausage technique are effective in 3D augmentation of deficient mandibular ridges especially concerning increase of vertical bone height. Ceramic membranes are relatively easier in application, associated with higher percentage of bone formation. However, wound dehiscence as a result of inadequate soft tissue coverage has to be taken into consideration to ensure more predictable results.