Objective: Caries risk is an accepted tool for planning caries evaluation and prevention activates. While weight has been investigated and linked to oral health in children and adolescents, there has been little work relative to the association of weight (i.e. BMI) and the oral health of hard tissue. In this study we examined whether a BMI measurement is associated with a patient’s DMFT score. Methods: Using HealthPartners medical and dental data systems 116,120 patients with both medical and dental coverage sometime between 2004 and 2012 were identified. DMFT scores were calculated for the last dental encounter within their period of enrollment. Their BMI was based on weight and height from their medical data. BMI ranges were divided into the four categories suggested by CDC (i.e. Underweight, Healthy Weight, Overweight and Obese) Patients were restricted to those 18 years and over and under 80. Analysis was done using EpiInfo. Results: Among the patients 58% were female. The average age was 43. The frequency within weights categories was; Underweight 3%, Healthy Weight 30%, Overweight 32% and Obese 35%. The mean DMFT scores were; Underweight 9.6, Healthy Weight 9.4, Overweight 10.8 and Obese 11.6. Controlling for age and gender and comparing to Healthy Weight all the BMI groups had significantly different DMFT scores (p<0.0001). Conclusions: The results of this study suggest that there is a relationship between a patient’s weight and their overall hard tissue status (i.e. DMFT). Weight may be serving as a useful proxy for dietary habits. This suggests that dentistry should investigate incorporating BMI categories into caries risk assessment.