Vitamin D has long been recognized for its immunomodulatory and anti-inflammatory properties, making it a plausible adjunct in the management of periodontal disease. This systematic review by Pesce and colleagues addresses a focused clinical question: does vitamin D supplementation, when combined with non-surgical periodontal therapy (NSPT), produce measurably better clinical outcomes than NSPT alone?

The authors conducted a systematic literature search across major electronic databases, selecting randomized controlled trials that evaluated the effect of vitamin D supplementation as an adjunct to scaling and root planing (SRP) in patients with periodontitis. Studies were assessed for methodological quality, and data were extracted focusing on key periodontal clinical parameters: probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), and in some cases systemic inflammatory markers such as C-reactive protein and interleukin profiles.

The findings indicate that vitamin D supplementation, when administered alongside NSPT, is associated with additional improvements in periodontal clinical parameters compared to NSPT alone. Reductions in PPD and gains in CAL were more pronounced in supplemented groups, and inflammatory markers showed a favorable trend. These effects are biologically coherent: vitamin D modulates the host immune response, downregulates pro-inflammatory cytokines, and may influence the subgingival microbial environment through its antimicrobial peptide-inducing activity — particularly via cathelicidin and defensins.

However, the review also highlights important limitations. Heterogeneity across included studies — in terms of vitamin D dosage, route of administration, supplementation duration, baseline serum 25(OH)D levels, and patient populations — makes direct comparison difficult and limits the strength of pooled conclusions. Many included trials were of moderate methodological quality, and follow-up periods varied considerably.

From a clinical standpoint, the take-home message is cautiously optimistic. Vitamin D deficiency is highly prevalent in the general population and has been independently associated with increased periodontal disease severity. Screening for vitamin D status in periodontal patients — particularly those with aggressive disease progression, poor response to conventional therapy, or systemic comorbidities such as diabetes and osteoporosis — appears clinically justified. Where deficiency is confirmed, supplementation is low-risk, inexpensive, and potentially beneficial beyond the periodontium.

For the periodontist and implantologist, this review supports integrating a broader systemic perspective into patient evaluation. Optimizing vitamin D levels before surgical procedures, periodontal or implant-related, may contribute to improved tissue healing and immune regulation. Larger, well-standardized RCTs are needed to establish definitive protocols, but the existing evidence is sufficient to prompt a conversation with patients about their nutritional status as part of a comprehensive periodontal care plan.