Traditionally classified as a vitamin, vitamin D represents a group of fat-soluble secosteroids with D2 (ergocalciferol) and D3 (cholecalciferol) being the most relevant of the group. The importance of this prohormone exceeds its known ability to maintain intra- and extracellular calcium and phosphate concentrations, thereby preserving essential metabolic functions such as the promotion of mineralization and maintenance and remodeling of the bone. Current observational research recognizes the potential antiproliferative, prodifferentiative, and immunomodulatory effects of vitamin D and its metabolites in the human body. The purposes of this paper are to: (1) review how vitamin D interacts in the body, its deficiency at the population level, and how it relates to oral health in children; and (2) assess proposed biological mechanisms by which vitamin D may play a preventive role in the development of dental caries.