Impact of Place on Dental Use by Medicaid-Enrolled Adults in Massachusetts

Abstract

Introduction:

Place-level factors influence oral health disparities, yet research predominantly focuses on individual-level determinants. This study examines how neighborhood characteristics influence dental service utilization among Medicaid-enrolled adults in Massachusetts.

Methods:

This retrospective study analyzed data from adult Medicaid beneficiaries obtained from the 2015 Massachusetts All-Payer Claims Database, which includes dental, medical, and member eligibility information. ZIP Code Tabulation Area (ZCTA)–level Social Vulnerability Index (SVI) scores for 4 themes (socioeconomic status, household characteristics, minority status, housing/transportation) were calculated using American Community Survey 2015 data. Negative binomial regression analysis with multilevel modeling assessed the association between individual- and place-level factors on the utilization of preventive, restorative, and surgical dental care.

Results:

The sample comprised 1,108,378 Medicaid beneficiaries across 511 ZCTAs and 13 counties in Massachusetts. ZCTA-level factors demonstrated several disparities. ZCTA with a low vulnerability for minority status SVI had up to 5-fold higher utilization across preventive (incidence rate ratio [RR]: 5.06, confidence interval [CI]: 3.67 to 6.97), restorative (RR: 5.28; CI: 3.88 to 7.17), and surgical (RR: 4.78; CI: 3.56 to 6.40) service types compared with high-vulnerability areas (predominantly minority ZCTAs). In addition, low-vulnerability neighborhoods for housing/transportation showed higher utilization for all preventive (RR: 2.67; CI: 1.98 to 3.59), restorative (RR: 2.44; CI: 1.84 to 3.24), and surgical (RR: 2.20; CI: 1.68 to 2.88) service types. Compared with ZCTA-level factors, individual factors such as age, gender, diabetes status, smoking status, and preventive medical care use contributed only marginally to explaining geographic variations in dental care use. Adding SVI themes reduced unexplained geographic variance by 38% for preventive services, 40% for restorative services, and 33% for surgical services.

Conclusions:

Place-based social vulnerabilities, particularly neighborhood racial composition and infrastructure, are stronger predictors of dental care utilization than are individual characteristics among Medicaid beneficiaries are. These findings reveal how structural inequities embedded in neighborhood environments create barriers to dental care access that persist even with insurance coverage.

Knowledge Transfer Statement:

This article examines the impact of place-related factors on dental service utilization among adult Medicaid beneficiaries in Massachusetts, focusing on ZIP Code Tabulation Area and county levels. It highlights the need to consider multilevel determinants in addressing disparities in access to dental care. By pinpointing predictors, this study supports interventions and policies to promote oral health equity and provides a foundation for further research to enhance outcomes for underserved groups.