Giant cell arteritis (GCA) is a polysymptomatic disease which constitutes an ophthalmic emergency because early recognition and management can prevent blindness. There is conflicting information in the literature on the validity, sensitivity, and specificity of various systemic symptoms and signs of GCA. This paper presents a review of our prospective studies on the subject, and our findings are particularly relevant to dentists. We investigated 363 patients in a prospective study. Positive temporal artery biopsy was seen in 106 patients and negative in 257 referred for diagnosis of GCA. Systemic symptoms and signs of GCA and erythrocyte sedimentation rate (Westergren-ESR) and C-reactive protein (CRP) levels were compared in these two groups of patients. The odds of having a positive temporal artery biopsy (i.e., GCA) were 9.1 times greater with jaw claudication (pain in masticatory muscles on eating), 3.4 times with neck pain, 3.2 times with CRP > 2.45 mg/dL, 2.0 times with ESR 47.107 mm/hr, 2.7 times with ESR > 107 mm/hr, and 2.0 times when the patients were aged > or = 75 years. Other signs and symptoms did not show a significant association with a positive biopsy. Our study showed that "normal" ESR values do not rule out GCA but that CRP is a more useful test than ESR. Since jaw claudication is one of the most important symptoms of GCA, dentists should keep this possibility in mind when older patients come complaining of jaw pain while eating.