Effectiveness of interceptive orthodontic treatment in reducing malocclusions

Introduction: In this retrospective cohort study of the effectiveness of interceptive orthodontic treatment, we compared patients receiving interceptive orthodontic treatment with untreated control subjects.

Methods: Models were scored by using the index of complexity, outcome and need (ICON). Control models (n = 113) were archival and were selected based on malocclusion in the early mixed dentition and no orthodontic treatment during the subsequent 2 years. The patients (n = 133) were in the mixed dentition and consecutively treated in the University of Bergen orthodontic clinic. Initial ages were 9.4 years (+ or - 1.4) for the treated group and 9.3 years (+ or - 0.8) for the control group. The treatment took a mean of 27.2 months (+ or - 16.3) for the patients; the control group was observed for a mean of 24.4 months (+ or - 3.6). Subject Groups were matched for age, need, complexity, duration, and all ICON components except spacing (P <0.006) and crossbite (P <0.000).

Results: ICON scores decreased after treatment by 38.8% (P <0.0001) from 54.9 (+ or - 16.6) to 33.6 (+ or - 16.1). The controls were unchanged, with ICON scores of 54.0 (+ or - 14.8) and 54.2 (+ or - 16.9). Improvement grades were different (P <0.0001), with most controls categorized as "not improved or worse" (89.4%), whereas only 36.1% of the treated group were in that category. However, there were increases in the "minimal," "moderate," and "substantial" improvement categories for the treated subjects (22.6%, 21.1%, and 17.3%, respectively). The controls did not change in any ICON component and worsened in crowding (P <0.007), whereas the patients improved in esthetics, crowding, crossbite, and overbite (P <0.007).

Conclusions: These results indicate that interceptive orthodontic treatment is effective for improving malocclusion but does not produce finished-quality results.