Posttreatment and retention outcomes with and without periodontally accelerated osteogenic orthodontics assessed using ABO objective grading system

Background: The posttreatment and retention outcomes following nonextraction orthodontic therapy, with and without corticotomy, were assessed using the American Board of Orthodontists objective grading system (OGS). Purpose: The purpose was to determine if the course of retention was any different following alveolar decortication and augmentation bone grafting, i.e., periodontally accelerated osteogenic orthodontics (PAOO). Materials and Methods: Study casts and panoramic radiographs of patients with and without PAOO (28 subjects each) were selected on the basis of the following: (1) comprehensive nonextraction orthodontic treatment using straight wire edgewise appliances for Class I crowding, (2) availability of immediate posttreatment records and retention records at least 1 year post de-bracketing, and (3) use of Hawley removable retainers with similar wearing instructions. Results: Independent and paired t-test statistical testing revealed the following: (1) Posttreatment orthodontic outcomes were the same, with or without corticotomy. (2) During retention, 5 of 8 ABO grading criteria improved for the sample without corticotomy, and 6 of 8 ABO grading criteria improved for the group with corticotomy. (3) Retention outcome scores were lower (better) for alignment and marginal ridges in the corticotomy-facilitated group. (4) The total score was significantly lower (better) for the corticotomy group at retention and the increment of total score change decreased (improved) significantly more during retention following corticotomy. Conclusions: The retention phase was more favorable following corticotomy because the amount of OGS total score change demonstrated a significantly improved retention outcome following PAOO therapy