Relationship of 3 indexes of orthodontic treatment need used by Medicaid and oral health–related quality of life

Abstract

This study aimed to assess the relationship between 3 indexes of orthodontic treatment need that are used by Medicaid, namely the Salzmann Index (SI), the handicapping labiolingual deviation (HLD) Index, and the HLD California Modification Index, and oral health-related quality of life (OHRQOL). The orthodontic records of 100 participants aged 11-14 years were used to calculate occlusal index scores. The condition-specific oral impacts on daily performances (OIDP) index questionnaire was used to quantify OHRQOL and to identify detriments attributable to malocclusion-related conditions (MRCs). The relationship between occlusal index scores and OHRQOL was analyzed using descriptive statistics, Spearman rank-order and biserial correlations, and logistic regression. The mean index scores were: SI, 15.4; HLD, 13.2; and HLD California Modification, 15.8. Ninety percent of participants did not have normative orthodontic treatment need according to current index criteria. OIDP scores were not normally distributed, and the mean score was 3.1. Of those participants who reported an impact, 83% attributed at least 1 of those impacts to MRCs; however, 90% of these were of mild or moderate intensity. Smiling was the performance most impacted by MRCs. The only statistically significant correlation between an occlusal index and OIDP scores was for the SI, though this association was weak (r= 0.27). None of the variables used in the logistic regression model (age, sex, 3 index scores) were significant predictors of OHRQOL. No meaningful association exists between the 3 indexes studied and OHRQOL. These findings challenge the validity of current systems for the allocation of Medicaid-funded orthodontic treatment.