Medicaid and privately financed orthodontic patients have
similar occlusal and psychosocial outcomes
Gregory J. King, DMD, DMSc; H. Asuman Kiyak, PhD; Geoffrey M. Greenlee, DDS, MSD, MPH;
Greg J. Huang, DMD, MSD, MPH; Charles F. Spiekerman, PhD
University of Washington, School of Dentistry, Seattle, WA
Abstract
Objective: This study compares occlusal and psychosocial outcomes from compre-
hensive orthodontic treatment in Medicaid (MC) and privately financed (private
pay, PP) patients.
Methods: Two cohorts received comprehensive orthodontics: MC (n = 66); PP
(n = 60). A calibrated, blinded examiner scored dental casts at baseline (pretreat-
ment, T1) and after completing 2 years of treatment (posttreatment, T2) using the
Peer Assessment Rating (PAR) and the Index of Complexity, Outcome, and Need
(ICON). The prevalence of patients in the validated ICON categories for treatment
need, complexity, and improvement were calculated. Questionnaires to assess body
image (BI) and expectations/experiences were administered. Occlusal measures at
T2 were compared after adjustment for baseline characteristics. Psychosocial mea-
sures were compared between and within groups. Occlusal and psychosocial asso-
ciations were evaluated.
Results: MC was 1.3 years younger (P < 0.001) and had worse malocclusions at base-
line (PAR 32 versus 25; P < 0.001); (ICON 64 versus 56; P = 0.06). After adjustment
for age and initial severity, estimated average differences between groups at T2 (MC-
PP) were slight: 1.5 [95 percent confidence interval (CI) -2.9, 5.9] and 2.4 (95
percent CI -4.4, 8.9) for PAR and ICON, respectively. More PP completed treatment
under 2 years (85 percent versus 62 percent; P = 0.03). At baseline, both groups
needed treatment, but MC malocclusions were more complex (P = 0.05). At T2,
both groups were acceptable and there were no differences in ICON improvement
categories. Group differences in psychosocial measures and associations between
psychosocial and occlusal measures were evident in the “teeth” domain but weak or
lacking elsewhere.
Conclusions: Occlusal and psychosocial outcomes from orthodontics in MC and PP
were comparable, despite worse MC malocclusions at baseline.
Introduction
Access to orthodontic services for children of low-income
families is severely limited compared with the general popu-
lation (1-3). Although the sources of this disparity are
complex, one key component is a shortage of providers who
accept Medicaid (MC) patients (4). Orthodontists and family
dentists cite barriers for why they elect not to be MC provid-
ers in three general categories: low reimbursement rates,
complexity of public programs, and patients who are at high
risk for poor outcomes (2,5).
Compromised orthodontic results are associated with
issues related to the nature and severity of the malocclusion
(6,7); the skill of the clinician (8,9); and poor patient compli-
ance (10).A case-control study comparing the effectiveness of
early partial orthodontic treatment in MC and privately
financed patients found that, despite indications of poorer
compliance in MC patients, comparable early treatment
results were obtained in both groups (11). Comprehensive
orthodontic treatment is significantly more complex and
compliance dependent than early treatment and, because
the patients are older, psychosocial and developmental
Keywords
malocclusion; orthodontics; corrective;
Medicaid; occlusal; dental health services;
financing; public; body image.
Correspondence
Dr. Gregory J. King, Department of
Orthodontics, University of Washington,
School of Dentistry, Box 357446, Seattle,
WA 98195-7446. Tel.: 206-543-2533;
Fax: 206-685-8163; e-mail:
gking@u.washington.edu. Gregory J. King, H.
Asuman Kiyak, Geoffrey M. Greenlee, Greg J.
Huang, and Charles F. Spiekerman are with the
University of Washington, School of Dentistry.
Received: 5/18/2011; accepted: 8/5/2011.
doi: 10.1111/j.1752-7325.2011.00288.x
Journal of Public Health Dentistry . ISSN 0022-4006
1 Journal of Public Health Dentistry •• (2011) ••–•• © 2011 American Association of Public Health Dentistry