Serum 1,25(OH)D level increases after elimination of periodontal inflammation in T1DM subjects.

Objectives: The aim of the present study was to investigate associations between serum concentrations of vitamin D metabolites, 25-hydroxyvitamin D [25(OH)D], and its active form, 1,25-dihydroxyvitamin D [1,25(OH)D], and the severity of chronic periodontitis.
Subjects and Design: Presence of dental plaque, probing pocket depth (PD), and attachment level in 80 type 1 diabetes mellitus subjects were recorded. The serum levels of 25(OH)D, 1,25(OH)D, ultrasensitive C-reactive protein, IL-6, TNF-α, high-density lipoprotein cholesterol, and glycosylated hemoglobin (percentage) were determined. Multivariate regression models were used to explore the associations between serum 25(OH)D (nanomoles per liter) and 1,25(OH)D (picomoles per liter) levels and periodontal health status.
Intervention: Antiinfective periodontal therapies were delivered and the clinical examination and laboratory analyses were repeated 8 weeks after the therapies.
Results: A statistically significant association was found between the serum level of 1,25(OH)D (odds ratio 1.06, 95% confidence interval 1.02-1.11) and periodontal health at the baseline; subjects with a high level were more likely to belong to the group of no or mild periodontitis. The serum level of 1,25(OH)D showed a statistically significant increase after antiinfective periodontal therapy in both no or mild (P = .001) and moderate or severe periodontitis (P < .001) subjects. The association between serum 25(OH)D level and periodontal health was negligible.
Conclusion: This study has shown a significant positive association between the serum 1,25(OH)D level and periodontal health status. To what extent this association is causal in nature remains to be confirmed.