Long-term occlusal changes and patient satisfaction in patients treated with and without extractions: 37 years after treatment.

INTRODUCTION: The objective of this research was to evaluate the treatment outcomes, long-term occlusal changes, and patient satisfaction after 37 years of nonextraction and extraction treatments. METHODS: Fifty-seven patients with Class I and Class II malocclusion were divided into 2 groups. Group 1 included 16 patients treated with nonextraction therapy, with mean initial (T1), final (T2), and long-term posttreatment (T3) ages of 13.2, 15.0, and 50.3 years, respectively. Mean treatment time (T2 - T1) and long-term follow-up time (T3 - T2) were 1.8 and 35.2 years, respectively. Group 2 included 41 patients treated with extraction of 4 first premolars, with mean ages at T1, T2, and T3 of 13.3, 15.6, and 53.6 years, respectively. Mean treatment (T2 - T1) and long-term follow-up (T3 - T2) times were 2.3 and 37.9 years, respectively. The Peer Assessment Rating (PAR) index and Objective Grading System (OGS) indexes were evaluated at T1, T2, and T3 stages. The subjects also answered an online questionnaire regarding esthetic and occlusal self-perception at T3. Intergroup comparison was performed with t tests. RESULTS: The PAR index improved with treatment and similarly worsened at T3 for both groups. OGS scores were close to the passing score at T2 for both groups. The nonextraction group presented worse OGS scores at T3 than the extraction group. Nonextraction patients perceived more changes in alignment over time, but overall satisfaction was similar. CONCLUSIONS: The PAR index improved with treatment, and the PAR and OGS scores showed a significant increase, indicating great occlusal changes in the long-term stage. The nonextraction group showed more occlusal changes and perceived more changes in their alignment over time, but overall patient satisfaction was similar in both groups.

Anterior tooth alignment and arch dimensions changes: 37-year follow-up in patients treated with and without premolar extraction.

INTRODUCTION: The objective of this research was to evaluate the anterior tooth alignment and dental arch dimension changes after orthodontic treatments with and without premolar extractions in the long-term. METHODS: Fifty-seven patients with Class I and Class II malocclusion were divided into 2 groups. Group 1 included 16 patients treated with nonextraction therapy, with mean initial (T1), final (T2), and long-term follow-up (T3) ages of 13.20 years, 15.07 years, and 50.32 years, respectively. The mean treatment (T2 - T1) and long-term follow-up (T3 - T2) times were 1.86 years and 35.25 years, respectively. Group 2 included 41 patients treated with extraction of 4 first premolars, with T1, T2, and T3 ages of 13.31 years, 15.63 years, and 53.60 years, respectively. The mean treatment and long-term follow-up times were 2.32 years and 37.96 years, respectively. The mean retention time was 2.26 years for both groups. The dental casts were obtained and digitized at T1, T2, and T3 stages. The following measurements were obtained: Little irregularity index, arch length, perimeter, and intercanine, interpremolar, and intermolar widths. Intragroup and intergroup comparisons were performed with repeated measures analysis of variance and t tests, respectively. RESULTS: Anterior tooth irregularity index increased at T3 in both groups. In addition, all arch dimensions, except the intercanine width, were significantly smaller in the extraction group at T3. Both groups showed similar arch dimension changes at T3, except for the mandibular arch perimeter. The percentage of mandibular anterior tooth alignment change was significantly greater in the nonextraction than in the extraction group. CONCLUSIONS: There was no difference in the changes of anterior alignment and transverse arch dimensions in patients treated with and without premolar extraction at T3, but the percentage of mandibular anterior tooth alignment changes was higher in the nonextraction than in the extraction patients at T3. The mandibular arch perimeter showed more of a decrease at T3 in extraction patients.