Radiographic Analysis of Crestal Bone Resorption in Vertical Ridge Augmentation

Objectives: The use of guided bone regeneration (GBR) has been shown to restore the reduced alveolar bone volume. Currently, there is limited research on looking at radiographic changes in bone height following restoration in vertical ridge augmentation. The aim of this retrospective study is to evaluate bone level changes after five years of loading in vertical ridge augmentation in implant placement.
Methods: Data for this study was collected from the electronic health records (EHRs) of patients who underwent vertical ridge augmentation of alveolar bone from July 1, 2006 to September 1, 2012 at Tufts University School of Dental Medicine. Bone level changes observed in the 5-year post loading of implants placed with vertical ridge augmentation and pristine bone were compared. The following patient-related and surgical variables were extracted from the EHRs: age, gender, smoking, history of periodontitis, sites of implant placement, types of implants, number, length and diameter of implants, type of bone graft materials, presence of periimplantitis, and implant failure. The inclusion criteria for the test group included partial edentulism of the mandible with two or three missing teeth, history of GBR with Seibert Class II, III ridge deformity, and 5 year post-operative radiograph following implant placement.
Results: 224 patients were identified after searching through the EHRs. After exclusion of 60 patients, a total of 164 patients (82 GBR and 82 control) were included in the study. There were 75 males and 89 females. There were no statistically significant differences for marginal bone changes (p=0.10) between the two groups.
Conclusions: The study showed that radiographic changes of the dental implant in regenerated bone were not significantly different from the changes in the native bone. However, there were patient and site-related factors that affected the long-term outcome of the implants.