Date of Completion


Embargo Period



Dr. Helen Swede, Ph.D., M.S., Dr. Julie A. Wagner, Ph.D.

Field of Study

Dental Science


Master of Dental Science

Open Access

Campus Access


Background: Periodontitis remains a highly prevalent disease and an important public health problem in the United States. Risk factors for periodontitis have mainly focused on intrapersonal determinants such as poor oral hygiene, biofilm microbiota, smoking, and host immune response. This study aimed to develop a social ecological framework considering factors beyond the individual including interpersonal, organization, community, and policy. It was hypothesized that the burden of disease is dependent upon the distribution of periodontists, periodontists’ participation in organized dentistry, and State oral health policies.

Methods: Disease prevalence was calculated using the National Health and Nutrition Examination Survey 1988 to 1994 (NHANES III) according to the American Academy of Periodontology/Centers for Disease Control and Prevention definition for moderate periodontitis. Contributory factors were investigated by surveying the distribution of periodontists and their participation in leadership, defined as holding an executive position within a State constituent society of the American Dental Association. State level oral health policy was assessed based on Medicaid coverage for periodontics according to the State Health Policy Monitor.

Results: The study included 6,216 adults at 13 states, descriptive data are presented in Table 1. Prevalence by state ranged from 7.0 to 36.8%. The ratio of periodontists per 100,000 population varied from 0.6 to 3.9; Massachusetts had the most periodontists per capita and Missouri had the least. Missouri also had the fewest practicing dentists per capita, 23.1 dentists per 100,000, California had the most with 63.2 dentists.

Periodontists represent 2.8% of practicing dentists and 3.1% of organized dentistry leaders. Periodontists represent 13.6% of practicing specialists and only 10.3% of specialists in leadership positions.

When comparing prevalence and Medicaid coverage, we observed a statistical trend (p=0.008) towards lower disease in states with coverage for periodontics (21.2% vs. 30.0%). Multivariate regression showed a protective effect of Medicaid on disease (p=0.010). The distribution of dentists had a positive correlation with disease (p=0.016), possibly signifying that general dentist distribution may not impact disease prevalence. The distribution and leadership of periodontists trended as protective factors to disease but did not reach statistical significance (p=0.292 and p=0.166, respectively).

Major Advisor

Dr. Effie Ioannidou D.D.S., M.D.Sc