A retrospective evaluation of 204 diagonal incisor malocclusion corrections in the horse.

The goal of this retrospective study was to record the direction of the diagonal incisor malocclusion (DIM) and excursion to molar contact (EMC) distances both before and after corrective procedures to determine if any general trends were apparent which may aid in predicting the outcome of DIM corrections. Pre-correction and post-correction data were compared to confirm a benefit to the patient from the corrective procedure. The results of this preliminary study reveal a few general trends to serve as basic guidelines for the practitioner Lateral EMC distances to the left and right in cases of DIM are commonly asymmetric. When prudently performed, corrective measures usually result in increased symmetry of EMCs. In cases of DIM, the side with the shorter EMC is more likely to remain the same rather than change after DIM correction. Decreases of EMC in one or both directions are much more common than increases in EMC after correction. In 100-300 quadrant DIMs, the EMC to the right will most likely decrease and in 200-400 quadrant DIMs, the EMC to the left will most likely decrease. Despite these helpful findings, the data obtained from this study strongly suggest the existence of multiple etiologies and progressive compensatory mechanisms complicating precise prediction of correction outcome.