Here are some studies about vitamin D and oral health:
Conclusion: 51 dental clinic patients were enrolled in a year-long study where half were given a low daily dose of vitamin D and calcium. Those receiving the supplements showed slightly better dental health.
Conclusion: People with higher vitamin D levels suffer less gingival inflammation
Association Between Serum Concentrations of 25-Hydroxyvitamin D3 and Periodontal Disease in the US Population (2004)
Conclusion: People with higher vitamin D levels over the age of 50 suffer fewer incidences of periodontal disease.
Conclusion: This article covers a multitude of studies that have found American blacks and American hispanics generally suffer much poorer dental health compared to American whites. Maybe it’s a socioeconomic thing and they can’t afford dentist visits. Maybe it’s a lifestyle thing. Or maybe it’s because vitamin D has been proven to be crucially important in dental and skeletal health, as vitamin D is required by the body to absorb calcium, and dark-skinned people in the west generally have lower vitamin D levels, which would contribute to tooth decay and poor oral health.
Conclusion: In a three year-long randomized control trial involving 145 subjects over the age of 65, those who took calcium and vitamin D supplements had better tooth retention compared to the placebo group.
Prevalence and Risk Indicators for Destructive Periodontal Diseases in 3 Urban American Minority Populations (2001)
Conclusion: This study found that American blacks suffer poorer oral and dental health compared to Asians and Hispanics. Although this study did not explore vitamin D as a factor, vitamin D has been proven to be a crucial factor in good oral/dental health and dark-skinned people tend to also suffer disproportionately from vitamin D-deficiency.