The excellence challenge in orthodontics: clinical use of an objective grading system for orthodontic cases

The aim of this study was to assess objectively some important factors for an accurate diagnosis and an optimal planning of finishing. The 8 criteria of the ABO "Objective Grading System"(OGS) were evaluated: alignment, marginal ridges, buccolingual inclination, overjet, occlusal contacts, occlusal relationships, interproximal contacts, and root angulation. This study focused on whether this method of evaluation is really applicable and useful in daily clinical practice.

15 subject (7 males, 8 females), with ages ranging between 8.5 and 55 years, were retrospectively examined. Both pre-treatment and post-treatment criteria were analyzed using the OGS, and measurements were made with the special device as described by the ABO. For each parameter that deviated from normal, 1 or 2 points were subtracted. Descriptive statistics were performed for OGS scores. Additionally, differences between scores for the pre-treatment versus the post-treatment were assessed using Wilcoxon signed-rank test.

All criteria used in the ABO OGS improved after treatment, except occlusal contacts. Alignment, overjet, occlusal relationships and root angulation improved significantly after treatment (p < .05). Marginal ridges, buccolingual inclination, interproximal contacts measurement did not show statistically significant differences between pre-treatment and post-treatment (p > .05).

Only 3 of 15 examined cases lost 30 points or fewer and would have passed the ABO Phase III examination. Quantitative evaluation of the OGS criteria might help to attain better scores and achieve a more functional and aesthetic outcome. Pre-treatment and post-treatment use of this system can help clinicians to assess treatment difficulties, to set goals and achieve an achieve an objective finishing for completed patients.