OBJECTIVES: Vitamin D has been reported to be crucial for bone mineralization and to play a significant role in immune and inflammatory responses. Its deficiency has been stated to be highly prevalent and might alter osseointegration of dental implants. Successful osseointegration has been claimed to be a critical aspect of implant survival and the effects of vitamin D on implant osseointegration have not been well documented. This study aimed to evaluate bone markers and cytokine levels of patients with or without vitamin D insufficiency. MATERIAL AND METHODS: A total of 42 patients were included and divided into two groups: vitamin D insufficient (Group IN-S
n = 21) and vitamin D sufficient (Group S
n = 21). Besides clinical periodontal parameters and implant stability measurements, the levels of RANKL, OPG, osteocalcin (OC), calcium (Ca), tumor necrosis factor alpha (TNF-α), IL-1β, caspase-1 (CASP1), and IL-10 in bone biopsy from implant preparation sockets and peri-implant crevicular fluid (PICF) were determined by enzyme-linked immunosorbent assay (ELISA). The results were represented as concentration and total amount. RESULTS: PICF RANKL levels (both concentration and total amount) were higher in patients with Vitamin D insufficiency compared to sufficient controls (p <
0.05). Concentration and total amount of IL-10 were significantly lower in vitamin D insufficient participants than those of vitamin D sufficient group (p <
0.05). No differences were detected between the groups in terms of other parameters. Bone levels of all evaluated parameters also did not differ between the groups (p >
0.05). CONCLUSION: It may be concluded that a low serum level of vitamin D may affect peri-implant health through altering IL-10 and RANKL.