De wisselwerking tussen reumatoïde artritis en de weefsels in en rond de mond.

The overall subject of this project is the interaction between rheumatoid arthritis and the orofacial tissues, being explored in a multicenter, observational prospective cohort study. In this study three groups will be compared: (1) patients with an early stage of rheumatoid arthritis, (2) patients with an increased risk of developing this disease, and (3) a control group with no auto-immune conditions. The groups will be compared on several intra- and extra-oral aspects: the temporomandibular joint, the presence and composition of dental plaque, bacteria in saliva and on the tongue, and periodontal condition. At baseline, possible differences in the oral microbiome and prevalence of diseases of the orofacial tissues will be studied. Over time, at 6 months, 1 year, 2 years and 3 years after baseline, this study will focus on the general health of subjects, with specific interest in the possible development of RA in group 2 and the RA disease status of patients in group 3.

All patients will be recruited in the Netherlands, with groups 1 and 2 being recruited at Reade (a center for revalidation and rheumatology in Amsterdam), and group 3 at the Academic Centre for Dentistry Amsterdam.

The aim of this research is to compare patients with early rheumatoid arthritis and patients with an increased risk of developing this disease to a control group with no auto-immune conditions on the prevalence of diseases of the orofacial tissues. Participants will be compared on several intra-oral and extra-oral aspects: the temporomandibular joint, the presence and composition of dental plaque, bacteria in saliva and on the tongue, and periodontal condition. New insights gained from this research might be useful during monitoring and treatment of patients with (an increased risk of developing) rheumatoid arthritis.

- Temporomandibular Joint Dysfunction: baseline.

- Serological precursors for rheumatoid arthritis: baseline.



- Microbiological composition: baseline. Within group 2 (patients with an increased risk of developing RA), a subgroup will be recognized, consisting of patients taking part in an already ongoing study (NL47550.048.13) on the effects of statins on the development of RA. In these patients, an extra timepoint at 3 months and 6 months after baseline will be added for the microbiological composition.

- Quantity of fluorescent dental plaque in relation to nutrition: baseline.

- Periodontal health: baseline (and a short evaluation of periodontal health at 3 months and 6 months for the subgroup in group 2).

- Immuno-biochemical characteristics: baseline.

- Oral health: baseline.

- General health: baseline, 6 months, 1 year, 2 years, 3 years.

- Oral Health Impact Profile: baseline.

- Patient reported outcomes of physical function, pain and global status: baseline

This is an observational study, no intervention takes place.