The effectiveness of phase I orthodontic treatment in a Medicaid population.

Background: The effectiveness of early orthodontic treatment for Medicaid-enrolled children in the mixed dentition was assessed and compared with results in a population of private-pay patients.

Material: Pre- and posttreatment casts from 196 subjects treated with interceptive orthodontics in the mixed dentition were evaluated by using the peer assessment rating (PAR) index and the index of complexity, outcome, and need (ICON). Ninety-six of the patients were treated at Odessa Brown Community Clinic in Seattle; their treatment was paid by Medicaid. One hundred private-pay patients were treated at the University of Washington graduate orthodontic clinic. The Medicaid and private-pay populations were comparable with respect to initial severity of malocclusion, as assessed by both indexes.

Results: PAR and ICON scores fell by similar amounts in the Medicaid (44.1% and 37.5%, respectively) and private-pay (46.8% and 37.3%, respectively) populations. Thus, the groups exhibited similar degrees of improvement with interceptive orthodontic treatment. According to the PAR and ICON, midline discrepancy, overjet, and esthetics exhibited the greatest improvement. The Medicaid population missed significantly more appointments and had poorer oral hygiene than the private-pay group, but these factors did not appear to worsen the outcomes, as measured by the 2 indexes. An appliance with 2 bands and 4 brackets was the most commonly used, and it produced the most significant treatment effect.

Conclusions: Phase I orthodontic treatment significantly reduces malocclusion severity in Medicaid and private-pay populations. There was no difference in initial severity or final outcome, as assessed by the PAR and ICON, between Medicaid and private-pay populations. The degree of improvement in PAR scores did not appear to be associated with compliance.