Randomized Clinical Trial (RCT) Comparing Interceptive and Comprehensive Medicaid Orthodontics

Objectives: Interceptive orthodontics (IO) has been proposed as a way to increase access to orthodontics for low-income children.  This report presents dental outcomes from a randomized clinical trial comparing IO to comprehensive orthodontics (CO) in Medicaid patients.

Methods: 170 pre-adolescent children with Medicaid eligible malocclusions were randomized to IO (n= 86) followed by observation (OBS) or OBS followed by CO (n=84). Casts at pre- (T1) and post-treatment (T2) were scored using the Peer Assessment Rating (PAR) and Index of Complexity, Outcome and Need (ICON) by calibrated examiners.  At T2, 64 IO casts were available and 67 CO models scored for ICON and 69 for PAR. Orthodontic outcomes at T2 were compared between treatment groups using linear regression.

Results: At T1, the groups were balanced based on age, gender, ethnicity, PAR /ICON and malocclusion complexity. Most were African-American with the remainder equally divided between Asians, Caucasians, Hispanics and others. Most malocclusions (78%) were rated as difficult-to-very difficult by ICON. At T2, PAR and ICON scores were significantly lower with CO compared to IO (PAR: 12.9/ 21.1; ICON: 28.5/40.9, respectively). These were significantly different even after adjusting for initial complexity, age, gender and ethnicity (p<0.001) with IO 13.1 (95%CI: 6.3,19.9) ICON points higher and 9.1 (95%CI: 4.6,13.7) PAR points higher than CO. CO improved more than IO (PAR: 18.5 [95%CI 15.0, 21.1] vs.10.0 [95%CI 6.7,13.4]; ICON: 44.8[95% CI 39.7, 49.9] vs. 35.0 [95%CI 29.5,40.5], respectively).

Conclusions: IO is an effective way to significantly reduce malocclusions in Medicaid patients, but does not provide equivalent results to CO.