A recent study aimed to assess the direct effect of intensive glycemic control on periodontal tissues in patients with diabetes mellitus.

In the study, published in Diabetes, Obesity, and Metabolism, researchers recruited 29 patients aged 20 to 75 years with type 2 diabetes (16 females and 13 males) who underwent a 2-week glycemic control regimen. The patients were hospitalized for 2 weeks to improve glycemic control. 

The study was conducted at Osaka University Hospital between December 2017 and March 2019. Exclusion criteria included severe hypoglycemia, advanced diabetic retinopathy, severe nephropathy (serum creatinine > 2.0 mg/dL), acute infection, severe trauma, active cancer, and recent surgery. The median age of the patients was 68.0 years, with a mean diabetes duration of 17.6 years. At baseline, the participants had an average of 21.4 residual teeth, a 32.9% bleeding on probing (BOP) rate, and a mean clinical attachment level (CAL) of 4.21 mm.

The researchers found that intensive glycemic control significantly improved periodontal inflammation in patients with uncontrolled type 2 diabetes, without any specific periodontal interventions. The 2-week hospital-based regimen led to significant reductions in the periodontal inflamed surface area, bleeding on probing, probing pocket depth, and clinical attachment level.

Among the key findings were:

• Glycated albumin levels decreased by an average of 4.32% (P < .05).
• HbA1c levels decreased by a median of 6.00 mmol/mol (0.500%) (P < .05).
• Periodontal inflamed surface area (PISA) decreased by a median of 10.9 mm² per tooth (P < .05).
• BOP rate decreased by a median of 16.7% (P < .05).
• Probing pocket depth (PPD) decreased by an average of 0.291 mm (P < .05).
• CAL decreased by a median of 0.326 mm (P < .05).
• Plaque index remained unchanged (P > .05), emphasizing that the improvements were tied to glycemic control rather than changes in oral hygiene practices.

The patients showed a bimodal response in periodontal healing, dividing them into two groups: 19 PISA-improved patients and 10 PISA-nonimproved patients. Those in the PISA-improved group demonstrated significantly greater reductions in their BOP rate, PPD, and CAL compared with the PISA-nonimproved group (P < .05 for all).

The PISA-improved (< 5.0 mm²) and PISA-nonimproved (≥ 5.0 mm²) groups were determined on the basis of changes in PISA per tooth. Paired t-tests, Wilcoxon signed-rank tests, Mann-Whitney U-tests, and correlation analyses were used to compare periodontal and systemic changes before and after treatment.

The researchers found baseline differences between the groups. The PISA-improved group had higher levels of systemic health markers such as:

• C-peptide: 1.81 ± 1.01 ng/mL vs 1.03 ± 0.73 ng/mL (P = .041)
• C-peptide index: 1.25 ± 0.70 vs 0.702 ± 0.395 (P = .031)
• CVRR during breathing: 3.55 ± 1.74% vs 2.34 ± 0.82% (P = .019)
• Ankle-brachial index: 1.11 ± 0.08 vs 0.946 ± 0.200 (P = .035).

In the PISA-improved group, changes in PISA per tooth positively correlated with changes in:

• Fasting plasma glucose (r = 0.472, P = .041)
• Acetoacetic acid (r = 0.570, P = .011)
• Beta-hydroxybutyrate (r = 0.500, P = .029).

Comprehensive assessments included blood tests, vital signs, and periodontal examinations. The periodontal measures included PPD, BOP, gingival recession, CAL, and plaque index at six sites per tooth. PISA was calculated using tooth type-specific formulas to quantify periodontal inflammation.

The study noted a bidirectional relationship between diabetes mellitus and periodontal disease. Few studies have explored the effect of diabetes treatment alone (excluding periodontal treatment) on periodontal disease pathology. The researchers hypothesized that improved glycemic control might affect the oral microbiome and reduce pathogenicity.

The concept of "metabolic memory" was discussed, suggesting that persistent hyperglycemia may impact inflammation and complications in patients with diabetes over time, potentially affecting vascular dysfunction and periodontal inflammation improvement.

The small sample size prevented multivariate analysis to identify specific factors associated with periodontal improvement. The focus on poorly controlled diabetes patients may limit generalizability to patients encountered in routine clinical practice.

The authors declared no conflicts of interest related to the research, authorship, and/or publication of this article.