Purpose: The treatment of gingival inflammation is associated with improved glycaemic control in diabetic patients. The goal of this parallel-randomised controlled trial (RCT) was to test the shortterm effects of professional oral hygiene procedures on plasma glucose levels in systemically healthy individuals. Materials and methods: Systemically healthy individuals with gingivitis and no sign of periodontitis were enrolled at a private practice in Italy. Patients were randomised to either a 1 hour (h) session of professional oral hygiene procedures or to 1 h in the waiting room. Not fasting blood glucose levels were assessed by a blind examiner at baseline (T0), 1 h (T1) and 2 h (T2) after procedures and finally 1 week after (T3). Oral hygiene procedures were then performed also in the control group. Results: Twenty patients were randomly allocated to each group. There were no drop-outs. Blood glucose levels at T0 (P = 0.0001) and time of measurement (P = 0.0001) were statistically significant, while oral hygiene procedures were not (mean difference between groups 0.77 mg/dl, 95%CI -2.64 mg/dl; 4.18 mg/dl, P = 0.6581). Mean blood glucose levels decreased between T0 and T1, were stable between T1 and T2 and showed similar levels to baseline after 1 week (T3) for both groups. Conclusion: This short-term RCT showed that professional oral hygiene procedures were not able to influence plasma glucose levels in individuals with gingivitis, but otherwise systemically healthy. Keywords: gingivitis, glucose level, glycaemia, treatment