Treatment of periodontitis for glycaemic control in people with diabetes mellitus.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 35420698 · doi:10.1002/14651858.CD004714.pub4
What was done
Authors searched six bibliographic databases to September 2021 for randomized controlled trials (RCTs) lasting at least 3 months comparing subgingival instrumentation (with or without surgical or antimicrobial adjunctive therapy) against no active treatment or usual care (oral hygiene instruction or supragingival scaling) in patients with diabetes mellitus and periodontitis. The primary outcome was HbA1c level.
What was found
The review included 35 parallel-group RCTs with 3,249 participants (almost exclusively type 2 diabetes; most conducted in secondary care). Periodontal therapy reduced HbA1c compared to control: - At 3 to 4 months: absolute reduction in HbA1c of 0.43% (4.7 mmol/mol; 95% CI -0.59% to -0.28%; 30 studies, 2,443 analysed participants; moderate-certainty evidence). - At 6 months: absolute reduction in HbA1c of 0.30% (3.3 mmol/mol; 95% CI -0.52% to -0.08%; 12 studies, 1,457 participants). - At 12 months: absolute reduction in HbA1c of 0.50% (5.4 mmol/mol; 95% CI -0.55% to -0.45%; 1 study, 264 participants). Reported harms were mild or balanced between groups, but adverse events were not evaluated in most studies.
Why it matters
This Cochrane update shifts earlier conclusions, providing moderate-certainty evidence that nonsurgical periodontal treatment yields a clinically meaningful improvement in glycaemic control for individuals with diabetes.
Limits
Only 2 of 35 included studies were judged at low risk of bias (14 high risk, 19 unclear risk), though a low-risk sensitivity analysis supported the main findings. Data apply almost entirely to type 2 diabetes (only one trial included type 1 diabetes), 12-month follow-up was limited to a single trial, and most studies did not systematically evaluate adverse events, cost, or long-term diabetic complications.
Cited by
- supports Periodontal disease and diabetes share a bidirectional relationship where gum disease impairs blood glucose control and fluctuating blood glucose exacerbates gum disease.