Acute dental pain elevates salivary oxytocin in women: a risk factor during pregnancy

Irreversible pulpitis is an acute, brief, and painful condition. Oxytocin, cortisol, and secretory immunoglobulin A (sIgA) are released by the body in response to pain and emotional stress. The aim of this study was to investigate the expression of salivary cortisol, sIgA, and oxytocin among patients with irreversible pulpitis. This was an ethically approved case-control study comparing 90 cases of irreversible pulpitis and 40 healthy individuals. Five study groups were established: nonpregnant female pulpitis, pregnant female pulpitis, male pulpitis, healthy (nonpregnant) female control, and healthy male control. Pregnant women in the first trimester were enrolled in the study. Participants received both clinical and radiographic examinations, completed a simple questionnaire related to food intake, habits, and anxiety, and their pain levels were recorded on a visual analog scale in which 0 represented no pain and 10 represented the worst possible pain. Unstimulated saliva samples were collected to measure oxytocin, sIgA, and cortisol levels. Dental pulp specimens were obtained and stained with hematoxylin and eosin to evaluate the agreement between clinical and histologic pulpal diagnoses. The statistical analysis included analysis of variance and Tukey tests. The majority of patients (37%) recorded a score of 8 (severe pain) on the visual analog scale, while a score of 10 (worst possible pain) was recorded only by pregnant women (3%). There was no statistically significant difference among healthy subjects for all salivary samples. Oxytocin levels increased significantly in nonpregnant (P < 0.5) and pregnant (P < 0.001) women with pulpitis. Cortisol (P < 0.01) and sIgA (P < 0.001) levels were significantly elevated only in pregnant women with pulpitis. The results of the present study indicate that acute dental pain during pregnancy can be considered as a pregnancy risk factor because of the resulting elevated oxytocin and cortisol levels.