Abstract Oral complications of RA may include temporomandibular joint disorders, mucosa alterations and symptoms of dry mouth. The aim of this study was to evaluate the salivary gland function of subjects with rheumatoid arthritis (RA) comparing it to healthy controls. Subjects with other systemic conditions known to affect salivary functions were excluded. A questionnaire was applied for the evaluation of xerostomia. Resting and chewing-stimulated salivary flow rates (SFR) were obtained under standard conditions. There were 145 subjects included of the study (104 RA and 38 controls). About 66.7% of the RA subjects and 2.4% in control group presented xerostomia. The median resting SFR were 0.24 ml/min for RA subjects and 0.40 mL/min for controls (p = 0.04). The median stimulated SFR were 1.31 mL/min for RA subjects and 1.52 ml/min for controls (p = 0.33). No significant differences were found between resting and stimulated SFR of RA subjects not using xerogenic medications and controls. There was significantly higher number of subjects presenting hyposalivation in the RA group than among controls, even when subjects using xerogenic medications were eliminated from the analysis. In conclusion, hyposalivation and xerostomia were more frequent among RA subjects not using xerogenic medication than among controls, although there were no significant differences in the median SFR between groups.

Low-dose methotrexate (MTX) is frequently used for patients with rheumatoid arthritis (RA). High doses of MTX frequently produce side effects. The aim of this study was to explore oral complications of low-dose MTX therapy in a population of RA patients. This is a cross-sectional study in which oral examination was performed on a population of RA patients. Patients undergoing MTX therapy (5-20 mg weekly) for at least six months were included in the study group, and RA patients being treated under another regimen were used as controls. The frequency of oral lesions was compared between groups. The chi-square test was used to compare frequencies. Relative risk (RR) and its confidence interval (CI) were established. Significance level was set at 0.05. Twenty-eight RA patients on a low-dose MTX regimen and 21 controls were enrolled in the study. Oral lesions were found in 22 patients (78.6%) undergoing MTX therapy, and in 5 patients (23.8%) undergoing other therapies (p < 0.001). There were no significant differences regarding age, gender or dosage. The most common oral events observed in patients in the MTX group were ulcerative/erosive lesions (60.7%) and candidiasis (10.7%). Patients in the control group presented lower prevalence of the same lesions (p < 0.001). The RR for developing oral lesions was 11.73 (CI 2.57 - 58.98), with low-dose MTX therapy. In conclusion, the prevalence of oral mucosa lesions in RA patients receiving low doses of MTX therapy is higher than in RA patients not receiving the drug.