Oral health and vitamin D in adult: a systematic review

This systematic review aimed to provide a synthesis of the evidence relating to how the provision of vitamin D supplements influences oral health status. An electronic database search was performed across six databases using a standardised search strategy. The PICO framework (Population, Intervention, Comparison, Outcome) was used to define the review question. The screening and selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses process (PRISMA). The quality of reporting was assessed using Consolidated Standards of Reporting Trials (CONSORT) guidelines, and the bias was assessed using the revised Cochrane tool RoB2. A total of 1812 studies were retrieved. 1427 studies were excluded due to unmet inclusion criteria. Full texts of seventy-five potential studies were retrieved and ultimately six studies met the inclusion criteria. There were limitations in the quality of reporting of studies (between 49 % and 73 %). 70 % of the risk of bias items were in the low risks category. Vitamin D interventions varied with respect to dosage and duration. Qualitative syntheses identified significantly better oral health outcomes. Heterogeneity of study design, intervention and outcomes precluded quantitative synthesis. Few clinical trials investigated the effect of vitamin D supplementation on oral health. There is considerable heterogeneity among studies interventions and oral health outcomes. Quality of reporting of studies has limitations and there is evidence of study biases. Nonetheless, qualitative synthesis of the evidence suggests that vitamin D supplements improve oral health outcomes, particularly periodontal health. Calcium may also play a significant role. Further high-quality trials are required of comparable vitamin D supplements with similar oral health outcomes focused to inform quantitative synthesis of the evidence.