Background: Periodontitis might have a direct role in initiating and sustaining the immunoinflammatory responses in RA.

Aim: to determine the prevalence of chronic periodontitis in a cohort of Egyptian RA patients, and their 1st degree relatives (FDR) compared to controls and its relation to serum Anticitrulinated peptides antibodies (ACPA).

Materials and Methods: Group I included 100 RA. Group II included 50 FDR free of clinical joint disease, Group III included 50 matched controls. DAS28 and HAQ were applied for all RA. Dental examination for all subjects including: Probing Pocket Depth (PPD), Clinical Attachment Loss (CAL), Plaque Index (PI), and Modified Gingival Index (GI). ACPA in serum was done for Groups I and II, Group III with Periodontitis.

Results: Group I had significantly more periodontitis than II and III.A statistically significant difference between group I and II in PPD, CAL, and PI, and between group I and III in PPD, CAL, and PI. In group I, 82% had positive ACPA (≥20 U/ml), compared to only 8% in group II and 0% in group III. There was a significant difference in serum ACPA between groups I and II, and I and III.

Conclusion: our study shows that individuals with RA are more likely to experience periodontitis.