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The use of corticocancellous bone grafts for
The use of corticocancellous bone grafts for ridge augmentation in implant dentistry was first reported by Breine and Branemark [25]. The revascularization of corticocancellous block grafts takes place at a much faster rate than in cortical bone autografts. Revascularization of block grafts enables maintenance of their vitality, and, hence, reduces chances of graft infection and necrosis [6]. Autograft is considered as the Gold Standard for bone transplantation [6] and various studies have shown efficacy for same [25–35]. It is osteogenic, osteoconductive and osteoinductive. Autografts can be derived from extra oral source (iliac crest, ribs) or intraoral source (chin, ramus). They can be used in block or particulate form [6]. Corticocancellous block grafts are preferred because of enhanced revascularization of the cancellous portion, and mechanical support and rigidity of the cortical portion, which ensures optimal ridge augmentation [31]. The healing of autogenous block grafts has been described as “creeping substitution” where viable bone replaces the necrotic bone within the graft and is highly dependent on graft angiogenesis and revascularization [6]. There is no risk of rejection or adverse immunological reaction with autogenous bone grafts. They are highly advantageous but are associated with some risks, such as donor site morbidity, limited bone availability, size mismatch, drooping of chin, nerve damage, tooth devitalization, gingival recession, increased postoperative discomfort, infection and blood loss [32]. In this case, autogenous corticocancellous block graft from ramus region was obtained of same surgical site, thus avoiding secondary site morbidity and used it for vertical and horizontal ridge augmentation in right side. The same was done in the left side. Bleeding points were created on recipient bed, which increases rate of revascularization, the availability of osteoprogenitor SRT 1720 and the rate of remodeling. Block graft was stabilized using titanium screws to avoid movement. The key to success is elimination of graft mobility and dead space between the graft and host bone [32,33]. Block grafts are associated with minimal resorption and do not usually require the use of an overlying membrane unless the dimensions of the graft are inadequate. Block grafts take longer to integrate than cancellous bone grafts. When a block graft is used, a staged surgical approach is recommended as opposed to placing the implants in conjunction with the graft [34]. The mandibular ramus is a useful, cortical graft that provides primarily dense. In addition, the mandibular ramus donor site is associated with fewer postoperative complications, in comparison to the symphysis region. Hence Anticoding strand can be successfully used for alveolar ridge augmentation prior to implant placement [35,36]. The mandibular second molar area provided the thickest cortical graft averaging range 2.0–4.2 mm. A cortical plate of 2.8 mm in average is enough to augment large defects [37]. This ramus block in one side provided enough bone to build horizontal and vertical walls in both right quadrants of the maxilla and mandible. The other side was enough to build the left side quadrants. In a longitudinal study [36] in which the Follow-up from dental implant placement ranged from 6 to 67 months (mean: 24.3–11.2 months). The overall survival rate was 96.9%. The 5-year cumulative survival rate was 88%, Marginal bone loss around implants ranged from to 3.3 mm (average: 0.22–0.45). Only 5% of the implants presented marginal bone loss more than 1.5 mm during the follow-up time [37–42]. CAD/CAM technologies have started a new age in dentistry. The quality of dental prostheses has improved significantly by means of standardized production processes. The CAD/CAM milled substructure allowed accurate making and checking of the final prosthesis. It also, allowed modifications of the substructure by the soft wear and eliminated the need for remake of the fabrication procedures in case modifications, addition or alterations were required [7,43].