Vitamin D is a fat-soluble secosteroid that plays a significant role in the whole body, including the maxillofacial region. The discovery of its receptors in many cells and organs made it possible to reveal the participation of vitamin D not only in the regulation of calcium phosphate metabolism, but also in immune processes, in providing anti-inflammatory and antimicrobial effects, slowing down cell proliferation and stimulating differentiation. In this literature review, we demonstrate the association between low vitamin D levels and the development of recurrent aphthous stomatitis, the course and response to treatment of squamous cell carcinoma of the oral cavity, the severity of periodontal diseases, and the processes of osseointegration and bone remodeling during dental implantation and guided tissue regeneration. The aim of our article was to demonstate a possible connection between vitamin D level and the oral diseases that can be presented at an oral surgery appointment, which will help clinicians to reduce the risk of early dental implant failure, ensure favorable outcomes of augmentative operations, as well as decrease the destructive effects of severe periodontitis and other conditions throug knowledge and timely lab tests and endocrinologist prescriptions.

Vitamin D is a fat-soluble secosteroid that plays an important role in the human body. There are two main native forms – vitamin D₃ (cholecalciferol) and vitamin D₂ (ergocalciferol). The regulation of calcium-phosphate metabolism and ensuring adequate bone remodeling are the most studied function of vitamin D. In recent years, researchers have found out the «extra-bone» effects of vitamin D and it allows us to be convinced of the great role of this compound. The participation of active forms of vitamin D in the processes of immunomodulation, anti-inflammatory, antimicrobial, antiproliferative effects and stimulation of cell differentiation are reflected in diseases of the maxillofacial region.In this article, we examined the main functions of vitamin D in the human body, the mechanisms of its action and influence on the occurrence and course of oral diseases. The discovery of the relationship between vitamin D deficiency and the processes of osseointegration, bone remodeling, the severity of chronic recurrent aphthous stomatitis, squamous cell carcinoma and periodontitis allow us to conclude that it is advisable to diagnose vitamin D deficiency in appropriate time and correction its serum level in dental patients.