Acute Dental Pain and Salivary Biomarkers for Stress and Inflammation in Patients with Pulpal or Periapical Inflammation

Aims: To investigate whether acute dental pain due to pulpal or periapical inflammation is associated with increased expression of cortisol and inflammatory markers and mediators in the saliva, as well as changes in salivary flow rate. Methods: Patients experiencing pain (n = 42) were recruited when seeking emergency dental treatment. A 0 to 10 numeric rating scale (NRS) was used as a measure of the severity of pain, and the number of days with pain sensation was also recorded. Unstimulated saliva was collected for 3 minutes (salivary flow measured in mL/minute) and stored at -80°C. Saliva was analyzed for the biomarkers cortisol, C-reactive protein (CRP), and cytokines interleukin-1β (IL-1β) and interleukin-6. In addition, the participants completed a simple questionnaire about stress-inducing factors such as insomnia, dental anxiety, or home/workplace stress. Patients received a dental examination and diagnosis (eg, symptomatic pulpitis/apical periodontitis or acute apical abscess), which was confirmed during dental treatment. The control group (n = 39) consisted of participants without any pain and no known medical or dental problems. Results: Patients experiencing acute pain due to pulpal or periapical inflammation had a mean NRS score of 7.0 ± 2.59. The mean duration of pain was 6.5 ± 7.9 days. There was no significant difference in pain level between male and female subjects, tooth type affected, or diagnosis. Higher levels of cortisol, IL-1β, and IL-6 and increased salivary flow were detected in patients with pain when compared to controls (P .05). CRP was higher in patients with acute pain compared to control participants without pain, but this difference was not statistically significant. Stress at home or the workplace was reported by 79% of patients experiencing pain and by 28% of control participants. Conclusion: Acute dental pain due to pulpal or periapical inflammation was associated with an increase in salivary cortisol, IL-1β, and IL-6 levels and in salivary flow rate. Stress arising from home or the workplace may aggravate a symptomfree pulpal or periapical inflammation to an acute phase. Inflammation in the pulp and periapical region can have effects in regions remote from the disease site. Keywords: cortisol, CRP, dental pulp. endodontic, IL-1β, IL-6, salivary flow rate