The effect of dental checkups on blood pressure was investigated. In 27 normotensive patients (13 men and 14 women) aged 22 to 64 years (mean 39.75 +/- 10.5 years), a 26-hour continuous, noninvasive blood pressure registration was carried out. Of each patient at least 175 blood pressure measurements were registered during these 26 hours, giving a total amount of 4725 blood pressure measurements. A dental checkup appointment with the family dentist was included. Blood pressure values displayed the well-known diurnal variation, but the visit to the dental surgeon was not accompanied by a rise in blood pressure. There was no significant difference between the blood pressure values during the 26-hour period and those during the checkup period. During a rest period after the dental checkup, neither the systolic nor the diastolic pressure fell to any degree in relation to the 26-hour values or the visit to the surgeon.