[Clinical effects of ridge augmentation with the half-columnar shaped mandibular bone block for the placement of dental implants].

OBJECTIVE

To evaluate the treatment effects of the half-columnar shaped mandibular block bone onlay grafting technique for augmentation of the resorbed maxillary anterior alveolar ridge after single tooth missing.

METHODS

A total of 15 sites of 14 patients received ridge augmentation surgeries. The recipient sites were prepared with trephines, the half-columnar shaped bone blocks were harvested from the ramus and external oblique ridges with trephines according to diameters of the recipient sites. The bone blocks were placed as lateral onlay grafts on recipient beds and secured by means of titanium screws. Particulate bone was added and absorbable membranes were used to stabilize and protect the grafts. After a mean interval of 4.5 months of healing the flaps were re-opened, the screws were removed and non-submerged implants were placed. The width and height of the alveolar ridges were recorded. After 3 months, implant-supported crowns were provided to the patients. One year later, the peri-impant condition and the marginal bone resorption on the proximal sites were observed.

RESULTS

Mean lateral augmentation obtained at the time of bone grafting was (3.8 + or - 0.8) mm, 5 out of 15 sites exhibited a mean of 3 mm of vertical augmentation. The mean healing time was 4.5 months, the mean percentage of horizontal and vertical bone resorption in the mean time were 8% and 7% respectively. No major complications were recorded at donor sites. No implant was lost during the study period. Clinical parameters and probing depth (< or = 4 mm) demonstrated the presence of a healthy peri-implant mucosa after 1 year of prosthetic reconstruction. The clinical and radiographic bone observations showed no more than 1.2 mm of resorption after bone graft and implant placement.

CONCLUSION

The half-columnar shaped mandibular bone graft (from the ramus and external oblique ridge) is a promising technique for bone augmentation in localized alveolar ridge defects after single tooth missing. This procedure offers easy access, good bone quantity for localized repair, low morbidity, decreased complaints of postoperative sensory disturbances or discomfort, minimal graft resorption, and a shorter healing time as compared with other methods for bone repair.