Objective: To determine and compare the distribution of Porphyromonas gingivalis fimA genotypes in type 2 diabetes mellitus (T2DM) patients affected by periodontitis, using non-diabetic subjects with and without periodontitis as control groups.
Material and methods: This study involved 75 subjects divided into three groups of 25 subjects each: Group 1 (non-T2DM without periodontitis), Group 2 (non-T2DM with periodontitis) and Group 3 (T2DM with periodontitis). The outcome variable was periodontitis, and explanatory variables were age, sex, T2DM and specific P. gingivalis fimA genotypes.
Results: In non-T2DM subjects with healthy periodontal tissues, type I fimA was the most frequently detected individually (40%) or in combinations (40%). In non-T2DM subjects with periodontitis, the most frequently detected type was Ib individually (20%) or in combinations (36%). In T2DM patients with periodontitis, the most frequently detected types were types I (20%) and III (20%), but there was no statistical difference (p>0.05) with non-T2DM periodontitis subjects.
Conclusions: Type I genotype was more frequently detected in periodontally healthy sites from non-T2DM subjects than in periodontitis sites from either subjects with or without T2DM. However, in sites affected by periodontitis from T2DM subjects the predominating types were I and III, which are less virulent strains of P. gingivalis.