Does nonsurgical periodontal therapy improve glycemic control?

Data sources The authors searched Medline via Pubmed, EMBASE, Cochrane Database of Systematic Reviews and Scielo. Additionally, grey literature was also searched with no restrictions regarding date of publication and journal up to March 2022. The search was conducted by two pre-calibrated independent reviewers using AMSTAR 2 and PRISMA checklists. Both MeSH terms, relevant free text and their combinations were utilised to conduct the search. Study selection The authors screened the articles on the basis of their titles and abstracts. Duplicates were removed. Full-text publications were evaluated. Any disagreement was resolved by discussion amongst themselves or with a third reviewer. Only the systematic reviews that included RCTs and CCTs were included involving the articles comparing nonsurgical periodontal treatment alone vs no treatment or nonsurgical periodontal treatment with adjunctive therapeutic modality (antibiotics, laser) vs no treatment or nonsurgical periodontal therapy alone. PICO method was used to define the inclusion criteria and changes in glycated haemoglobin post-intervention 3 months was taken as primary outcome. All the articles with the use of adjunctive therapy other than antibiotics (local or systemic) or laser were excluded. The selection was restricted to English only. Data extraction and synthesis Data extraction was performed by two reviewers. For each systematic review and each study, mean and standard deviation of glycated hemoglobin level at each follow-up, number of patients both in intervention and control group, type of diabetes, design of study, follow-up period, number of comparisons in meta-analysis, quality assessment of systematic review was assessed by 16 items AMSTAR 2 (Assessment of Multiple Systematic Reviews) and 27 itemed PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) checklist. JADAD scale was used to assess the risk of bias for included RCTs. Q test was used to calculate statistical heterogeneity and percentage of variation by I2 Index. Both Fixed (Mantel-Haenszel [Peto] test) and random (Dersimonian-Laird test) models were used to estimate individual study. Funnel plot and Egger’s linear regression methods were used to evaluate publication bias. Results Following initial electronic and hand search, 1062 articles were screened for title and abstract and 112 articles were considered for full text eligibility. Finally, 16 systematic reviews were considered for qualitative synthesis of results. 16 systematic reviews described 30 unique meta-analyses. Publication bias was assessed in nine out of 16 systematic reviews. Compared to control or non-treatment group, nonsurgical periodontal therapy resulted in statistically significant mean difference of −0.49% HBA1c reduction at 3 months ( p = 0.0041), −0.38% ( p = 0.0851). The effect of periodontal therapy with antibiotics compared to NSPT alone was not statistically significant (CI −0.32–0.06, 3 months; CI −0.31–0.53, 6 month). The effect of NSPT and laser vs NSPT for HbA1c was not statistically significant (CI −0.73–0.17, 3–4 month). Conclusions Based on included systematic reviews and limitations within the study, nonsurgical periodontal therapy is an effective treatment modality in glycaemic control in diabetic patients in terms of HbA1c reduction both at 3 months and 6 months follow-up. The adjunctive therapies like antibiotic administration whether local or systemic and use of lasers with NSPT does not show statistically significant differences as compared to NSPT alone. However, these findings are based on analysis of available literature based on systematic reviews on this subject.