Supracrestal Implant Placement Improves Peri-Implant Health in T2DM Patients: A Randomized Clinical Trial.

Resumo (EN)

Abstract
Objective: This study, designed as a randomized controlled trial, investigated how the vertical placement of implants influences peri-implant conditions in patients with type 2 diabetes mellitus (T2DM) treated with mandibular overdentures.

Material and methods: Twenty-two edentulous individuals with T2DM received two implants each in the anterior mandible following a split-mouth design: one placed at the crestal level (CL) and the other at a supracrestal level (SL). Clinical, immunoenzymatic, and tomographic assessments were conducted at prosthesis placement (baseline) and after 6, 12, and 24 months.

Results: Probing depth (PD) and clinical attachment level (CAL) were consistently higher in CL group than SL in all evaluated periods (p<0.05). Immunoenzymatic assay showed that CL implants demonstrated higher concentrations of IL-4, at 6, 12 and 24 months, and IL-21 at 24 months, when compared to SL implants (p0.05). Higher bone loss was detected in the first year of implant loading compared to the second year in both SL and CL group (p<0.05). In the SL group, the mean bone loss increased by 31.22% from baseline to 24 months, corresponding to a change of 0.74 mm. In the CL group, the initial variation was 1.21 mm (69.94%) over the same period.

Conclusion: These findings suggest that supracrestal implant placement may offer clinical and immunoinflammatory advantages in patients with T2DM, promoting better peri-implant health and reduced bone loss over time. Within the limitations of this study, SL positioning appears to be a favorable strategy for implant-retained overdentures in diabetic individuals. The clinical trial registry number is NCT03988140.

Clinical significance: Rehabilitating diabetic patients with dental implants can be challenging. This study demonstrates that supracrestally placed dental implants exhibit better clinical behavior in maintaining peri-implant health.