Comparison of university and private-practice orthodontic treatment outcomes with the American Board of Orthodontics objective grading system

Treatment outcomes and duration of treatment for patients treated in university graduate orthodontic programs and private orthodontic practices were assessed and compared with the ABO objective grading system.

The treatment records of 139 randomly selected adolescents who had received comprehensive orthodontic treatment were examined. Seventy-seven subjects had been treated in 3 postgraduate orthodontic clinics, and 62 had been treated in 3 private orthodontic practices. Pretreatment, all subjects had Class II Division 1 malocclusions and ANB angles equal to or greater than 4 degrees . All patients were treated with premolar extractions. Posttreatment dental casts were measured and scored with the ABO objective grading system.

No significant differences were found between the groups in the alignment, buccolingual inclination, and overjet components. Patients treated in private practice had significantly lower scores for marginal ridge height and occlusal relationship. Patients treated in the university programs had significantly lower scores for occlusal contact and interproximal contact components.

There was no significant difference in the overall score, thus no significant difference in the overall quality of orthodontic treatment outcome between patients treated in university programs and private practices. However, the university group had a significantly larger sample variance for the overall score. There was no significant difference in the duration of the treatment between patients treated in a university setting and in a private practice.