This comprehensive study was carried out to describe and analyze the oral health status, perceived oral health problems, patients' costs, and oral health behavior in a group of patients with primary Sjögren syndrome (PSS). In particular, the objective of this report was to assess whether Sjögren syndrome patients had more dental caries experience than a control group. Data were collected by means of interviews and clinical oral examinations. The study comprised 53 patients with PSS and a control group of 53 persons matched by age. Among the younger patients the number of decayed, missing, or filled teeth (DMFT) was 22.3, compared with 18.8 among controls (P< 0.05). In parallel, the DMFT in the old-age PSS patients was 26.2, against a DMFT of 22.1 for controls (P< 0.001). On average, the young patients had seven teeth missing, whereas two missing teeth were found among controls (P < 0.01). PSS patients had more frequent dental visits--every 3-4 months (40%)--than controls (19%). In parallel, 78% of the PSS patients brushed their teeth more than twice daily, compared with 28% of the control group. The PSS patient group reported having had more teeth extracted, more trouble with their teeth during lifetime, and higher expenses for dental treatment than controls. In spite of the more regular oral health care practices than the general population, PSS patients had experienced more dental caries and more radical dental treatment. It is suggested that the National Health Insurance should give emphasis to preventive care to patients with PSS.