Dental pain threshold and angina pectoris in patients with coronary artery disease

One hundred eight consecutive patients with proved coronary artery disease and reproducible exercise-induced myocardial ischemia were studied. During repeated exercise testing, 52 patients (Group I) had myocardial ischemia in the absence of pain (silent ischemia) whereas 56 patients (Group II) experienced anginal symptoms in the presence of electrocardiographic signs of ischemia. A pulpal test was carried out in all patients using an electrical dental stimulator commonly used in dentistry. Electrical current was delivered in increasing intensity from 10 to 500 mA, and the dental pain threshold and the reaction of the patients to maximal stimulation were determined. During the pulpal test, 71.2% of the patients in Group I did not experience pain, even at maximal stimulation (threshold 0), 11.5% were sensitive at threshold I (10 to 200 mA) and 17.3% felt pain at threshold II (210 to 500 mA). In Group II, 69.7% of the patients complained of dental pain at the low intensity test current (threshold I), 10.7% at threshold II and 19.6% at threshold 0. In Group I, 71.2% of patients did not have discomfort (reaction -), even at maximal stimulation, 21.1% had a mild reaction (reaction +) and 7.7% had an intense painful reaction (reaction ++). In Group II, 80.4% of patients were sensitive to the pulpar test (67.9% reported intense painful sensation at maximal stimulation, 12.5% had a mild reaction); 19.6% of patients had no reaction. The two groups of patients were similar with respect to age, sex and angiographic features