In the cross-sectional case-control pilot study, researchers enrolled 30 pregnant patients in Slovenia from 2012 to 2014, including 15 patients with type 1 diabetes mellitus and 15 healthy controls. Participants were matched by age, gestational week, body mass index, and former smoking status. All patients were between 28 and 34 weeks of gestation and had at least 20 natural teeth.
Researchers assessed plaque index, bleeding on probing, probing pocket depth, clinical attachment level, periodontal wound surface area, total periodontal inflammatory burden, inflammatory blood markers, and subgingival periodontal pathogens.
Patients with type 1 diabetes mellitus (T1DM) had higher mean bleeding-on-probing rates than controls, at 30% vs 20%, respectively. Mean plaque index values were also higher in the diabetes group, at 27% vs 14%.
Exploratory periodontal wound-area measures were numerically larger among patients with T1DM, but these differences did not reach statistical significance. Mean deep bleeding periodontal wound area was 5.5 cm² in the diabetes group vs 3.0 cm² in controls, and mean total bleeding periodontal wound area was 6.3 cm² vs 3.9 cm². The wound-area measurements represented calculated periodontal surface-area metrics derived from probing depth and tooth circumference rather than directly measured wounds.
No statistically significant differences were observed between groups in clinical attachment loss, probing pocket depth, inflammatory blood markers, or prevalence of periodontal pathogens. Patients with T1DM had numerically higher levels of Prevotella intermedia, Tannerella forsythia, and Treponema denticola, but these findings were not statistically significant.
HbA1c levels were significantly higher in the T1DM group, at 5.8% vs 5.1%. Notably, the T1DM cohort was managed with insulin pumps, suggesting that the observed periodontal differences were not limited to patients with markedly uncontrolled diabetes.
Within the diabetes cohort, older age was associated with greater total periodontal inflammatory burden. Longer duration of T1DM was associated with more bleeding on probing and greater periodontal inflammatory burden. Across the full study population, former smoking history was associated with greater clinical attachment loss, deeper probing depths, and higher periodontal inflammatory burden, although the subgroup included only eight former smokers.
The inflammatory-marker findings were mixed. High-sensitivity C-reactive protein and nitrous oxide levels trended higher in the T1DM group, whereas interleukin-6 and tumor necrosis factor alpha levels trended higher in controls, though none of these differences reached statistical significance.
The findings should be interpreted as exploratory. The study included only 15 patients per group, limiting statistical power and generalizability. The cross-sectional design also precluded causal inference, and multiple clinical, biochemical, and microbiologic variables were analyzed without correction for multiple comparisons.
The investigators additionally used exploratory logistic-regression modeling with group membership as the outcome variable, producing odds ratios that may not correspond to clinically meaningful thresholds.
The researchers also noted that participants were enrolled between 2012 and 2014, which may limit applicability to contemporary T1DM pregnancy management in the era of continuous glucose monitoring and hybrid closed-loop insulin-delivery systems.
The study did not adjust for oral hygiene behaviors, dental-care utilization, socioeconomic status, or frequency of prior dental care, all of which may have influenced the observed plaque-index differences.
The researchers concluded that pregnant patients with T1DM showed increased bleeding on probing and higher plaque levels compared with healthy controls, led by M. Janc of Periodontology, Private Practice, Ljubljana, Slovenia, and R. Schara of the Department of Oral Medicine and Periodontology, Faculty of Medicine, University of Ljubljana, Slovenia. The investigators added that the findings support early periodontal screening and ongoing periodontal follow-up in this patient population.
The findings align with existing recommendations that prenatal care for patients with T1DM include periodontal evaluation, although the small sample size limits how strongly this pilot can support that practice. Larger confirmatory studies are needed.
Disclosures: The study was self-funded by the Medical Faculty, University of Ljubljana, Slovenia. The researchers reported no conflicts of interest.
