Investigators analyzed the geographic distribution of dental deserts in the United States.

Although prior research has examined disparities in dental care among low-income and racial and ethnic minority populations, few studies have assessed the spatial accessibility of U.S. dental clinics. Geographic barriers to dental care can result in delayed treatment, worsening dental conditions, and poor oral health outcomes.

In a cross-sectional study published in JAMA Network Open, researchers used the IQVIA national practitioners’ database to assess spatial accessibility to dental clinics nationwide. The study included 205,762 active U.S. dentists, with data analyzed from November 2023 to April 2024. Using block group-level data, investigators mapped dental clinic availability and identified potential dental deserts—areas with limited access to dental care.

The analysis found that 7.5% of U.S. residents (n = 24.7 million) lived in areas with fewer than one dentist per 5,000 people, and 0.5% (n = 1.7 million) had no access to a dental clinic within a 30-minute drive. The ratio of dentists to residents was significantly lower in rural areas (1 dentist per 3,850 people) compared with urban areas (1 dentist per 1,470 people).

Further, counties and U.S. Census block groups with higher levels of Black and Hispanic segregation, socioeconomic deprivation, and uninsured populations were more likely to experience dental care shortages:

• Rural block groups were 23.9 percentage points (95% CI, 23.6-24.3) more likely to have shortages.
• Areas with high Black segregation were 1.5 percentage points (95% CI, 1.3-1.7) more likely to experience shortages.
• Areas with high Hispanic segregation were 4.5 percentage points (95% CI, 4.3-4.8) more likely to experience shortages.
• Areas with the highest levels of socioeconomic deprivation were 5.5 percentage points (95% CI, 5.1-5.9) more likely to have shortages.

The study identified Alaska, Montana, and North Dakota as having the highest proportion of residents in dental deserts. In contrast, Connecticut, Delaware, Indiana, and New Jersey had no block groups designated as dental deserts.

Companion Perspective: Harvard School of Dental Medicine

In a companion news article from the Harvard School of Dental Medicine, senior study author Hawazin Elani, BDS, PhD, Assistant Professor of Oral Health Policy and Epidemiology, emphasized the severity of the findings, stating:

"Our findings highlight a concerning geographic maldistribution of dentists, with many rural and disadvantaged communities left without access to care."

Coauthor Md. Shahinoor Rahman, PhD, added that the study’s approach allowed them to identify regions with limited access to dental care that may have been missed by previous studies.

The companion article further noted that 15.6% of residents in dental care shortage areas lived below the federal poverty level, and that racial disparities varied by location. While rural areas with shortages had a larger proportion of White residents, urban areas with high segregation and economic deprivation had a higher proportion of Black and Hispanic residents in dental care shortage areas.

Dr. Elani highlighted the policy implications of these findings, particularly for Medicaid and Medicare beneficiaries, stating:

"The situation is likely even more dire for Medicaid and Medicare beneficiaries, who face additional barriers due to low dentist participation, worsening existing disparities. This can lead to people putting off much-needed care due to access challenges."

The study authors suggested that these findings could inform workforce planning strategies and federal and state-level interventions to encourage more dentists to practice in underserved areas.