ASSESSING VALIDITY OF SALZMANN INDEX AND HANDICAPPING LABIOLINGUAL DEVIATION INDEX IN DETERMINING TREATMENT PRIORITY FOR ORTHODONTIC PATIENTS

Abstract

Objectives: More than 30 states use the Salzmann Index or the Handicapping Labiolingual Deviation Index to determine which patients receive tax-supported orthodontic treatment. The indexes use a criterion which produces a numerical value reflective of the severity of the malocclusion. The aim of the study is to evaluate the validity of these indexes by comparing subjective evaluations of orthodontic treatment need to objective scores produced by indexes of malocclusion. Methods: 20 orthodontic faculty and residents (VAS Group) were asked to evaluate the severity of malocclusion of 20 patients, prior to beginning orthodontic treatment, using a subjective scale, a Visual Analog Scale (from “No need for treatment” to “Severe need for treatment”). The 20 patients consisted of a variety of malocclusions including Class I, Class II, Class III, anterior crossbite, posterior crossbite, impaction. A separate group of 3 residents (IS Group) evaluated the same patient malocclusions using the aforementioned indexes of malocclusion. The results were analyzed to identify a correlation between the subjective scale (VAS) and objective scales (IS). Results: In total, 20 residents and faculty evaluated the severity of malocclusions. There was a weak correlation between the Salzmann scores and the Visual Analog Scale scores (Correlation Coefficient, R2=0.2359). There was a moderate correlation between the Handicapped Labiolingual Deviation index scores and the Visual Analog Scale scores (Correlation Coefficient, R2=0.4486). When comparing the faculty versus the residents in the VAS Group there was a strong correlation between them (Correlation Coefficient, R2=0.7901). Although, there was a strong correlation, on average the faculty scored the malocclusions with 15% more severe need for treatment than did the residents. Conclusion: Overall, there was a weak correlation for the Salzmann Index and a moderate correlation for the Handicapped Labiolingual Deviation Index, indicating neither indexes are optimal for evaluation of malocclusions. More emphasis has to be placed on identifying an objective method to evaluating the severity of malocclusions.