Interposed bone grafts to accommodate endosteal implants for retaining mandibular overdentures. A 1-7 year follow-up study.

The results are reported on 34 edentulous patients, who underwent interposed autogenous bone graft augmentation in the symphysis of the mandible, combined with bone-hydroxylapatite onlay augmentation of the area posterior to the mental foramina. Two to four implants were placed in the grafted symphysis after 3-5 months. An overdenture was constructed three months later. The follow-up period ranged from one to seven years. An average loss of mandibular bone height of 10-13% was observed. The data provided no evidence of a further time-dependent resorption from two-and-half to seven years.