Background

Chlorhexidine (CHX) is a broad-spectrum antimicrobial agent commonly used in medicine. Application of (CHX) during abutment connection reduced the bacterial load at the implant–abutment interface. We hypothesize this treatment may consequently reduce peri-implant soft tissue inflammation and marginal bone loss.

Purpose

To evaluate the effect of a single application of CHX gel inside the dental implant internal hexagon on peri-implant tissue.

Methods

Forty patients were recruited to this randomized, double-blinded, clinical trial. At the time of implant installation, a 4-mm healing abutment was connected to the implant. In the test group, chlorhexidine gel 1% was applied inside the implant hex, whereas control implants did not receive any gel. Clinical and radiographic measurements included soft tissue recession (REC), plaque index (PI), gingival index (GI), plaque index (PI), keratinized mucosa width (KM), probing depth (PD), and a peri-apical parallel x-ray. Peri-implant crevicular fluid (PICF) was collected for cytokine analysis. t-Test was used to compare changes from baseline to 3 months. Mann–Whitney U test and t test were used to compare test and control groups.

Results

Twenty patients in the test group and 17 in the control group completed the study. One implant in the control group failed to osteointegrate. There were no significant differences between the control and test groups for REC changes, bone loss, and PD. GI was significantly lower in the test group after 1 week (1.79 ± 0.24 vs 0.75 ± 0.18, respectively) and 3 months (1.18 ± 0.21 vs 0.25 ± 0.12, respectively) although PI was equal. At 3 months, interleukin 1-β (IL1-β) was higher in the control group (p < 0.01) and a positive correlation was found between GI and IL1-β (rs = 0.60424, p = 0.00032).

Conclusions

Application of chlorhexidine gel reduced inflammation and IL1-β levels in the peri-implant soft tissue.