Frequency of Porphyromonas gingivalis and fimA genotypes in patients with periodontitis and systemic lupus erythematosus.

OBJECTIVE: The objective of this study was to determine and compare the distribution of fimA genotypes of Porphyromonas gingivalis (P. gingivalis) in systemic lupus erythematosus (SLE) patients compared with control subjects. MATERIAL AND METHODS: This observational cross-sectional study included 281 patients divided into two groups. Group 1 (G1) consisted of 162 control subjects (30-54 years old) and, group 2 (G2) included 119 subjects (10-69 years old) diagnosed with SLE. The presence of P. gingivalis was detected by PCR. DNA sequences in acquired plaque samples were identified using P. gingivalis specific sequences and further analyzed to differentiate their fimA genotypes using six sets of fimA genotype-specific primers. RESULTS: The presence of periodontitis (PE) was similar in both groups; similar measurements were obtained regarding clinical attachment loss (CAL) (G1 1.76 ± 0.72 vs. G2 1.95 ± 0.76). G2 showed the highest frequency of P. gingivalis (94.95%). FimA genotype II is considered the most virulent and, was the most frequently found in the SLE group (53.09%). CONCLUSION: The genotypes associated with PE are more frequently detected in SLE, which could make them susceptible to develop PE.

Chitosan nanoparticles enhance the antibacterial activity of chlorhexidine in collagen membranes used for periapical guided tissue regeneration.

Endodontic failure is mainly associated with the persistence of microbial infection in the root canal system and/or the periradicular area. Microorganisms and their toxins located in the root canal system may trigger apical periodontitis and tissue destruction. Tissue regeneration in periapical surgery by using membrane barriers has shown an improved healing and bone closure. However, bacterial membrane contamination is a main reason of failure. In this in vitro study, different brands of chlorhexidine, a combination of chitosan nanoparticles containing chlorhexidine were tested against Enterococcus faecalis on agar plate's cultures and infected collagen membranes. Our results indicated that chitosan nanoparticles acted synergistically with chlorhexidine, inhibiting and eliminating significantly a greater amount of colony former units in both BHI-agar cultures and infected collagen membranes. These results suggested that chitosan nanoparticles could be used to improve regenerative procedures in periapical surgery.