Evaluation of orthodontic treatment, retention and relapse in a 5-year follow-up: a comparison of treatment outcome between a specialist and a post-graduate clinic.

The aim of this study was to evaluate and compare orthodontic treatment between a specialist clinic and a post-graduate clinic. A long-term follow-up study was done 5 years after orthodontic treatment ended. Eighty-one individuals treated at the Post-graduate clinic at the Department of Orthodontics, University Clinics of Odontology, Göteborg, and 84 individuals treated at the Orthodontic Specialist Clinic in Vänersborg, the county of Västra Götaland were examined. The Peer Assessment Rating (PAR) index was used on pre-, post-treatment and 5-year follow-up study casts. The percentage reduction in weighted PAR (WPAR) scores after treatment and at the 5-year follow up did not differ significantly between the clinics. There were significant higher pre-, post-treatment and 5-year follow-up PAR and WPAR scores in patients from the Specialist Clinic as compared with patients from the Post-graduate Clinic. In the whole sample 97.6% of the patients were improved or greatly improved after treatment and 95.8% were still improved or greatly improved 5 years after treatment. Sixty-seven percent of the patients still had retainers in one or both arches at the 5-year follow-up. The WPAR scores are one factor that indicates the high quality of the treatment process in both clinics. The higher post-treatment PAR scores in the Specialist Clinic may be because a larger number of patients were treated only in one jaw at this clinic.