Thermographic imaging of postoperative inflammation modified by anti-inflammatory pretreatment

The aim of this study was to assess the usefulness of thermography in detecting the postoperative inflammatory reaction after third molar removal.

Thermographic images (NovaTherm; Novamedix Ltd, Hampshire, England) of both cheeks were obtained on the first and seventh postoperative days after removal of impacted mandibular third molars under local anesthesia in 30 patients (15 men, 15 women). The unoperated contralateral side served as a control. One of the following pretreatments was given immediately before the operation: diclofenac (Voltaren; Novartis, Espoo, Finland) 150 mg orally (rapid-release 50 mg and prolonged-release 100 mg, n = 15), diclofenac 100 mg orally (prolonged-release) and 50 mg intramuscularly (n = 11), or placebo (n = 4).

The postoperative skin surface temperature on the operated side was significantly higher than that on the unoperated side. The thermal difference was 0.9 degrees C +/- 0.1 degrees C on the first postoperative day and declined significantly by the seventh day to 0.3 degrees C +/- 0.1 degrees C (both P < .001). The thermal difference in patients receiving diclofenac preoperatively was significantly smaller (0.8 degrees C +/- 0.1 degrees C at day 1 and 0.2 degrees C +/- 0.1 degrees C at day 7) than in patients receiving placebo (1.6 degrees C +/- 0.1 degrees C at day 1 and 0.8 degrees C +/- 0.3 degrees C at day 7, P < .001). However, with equal doses of diclofenac, the combination of rapid-release and prolonged-release tablets orally was more effective in reducing skin temperature than an orally administered prolonged-release tablet combined with intramuscular injection (P < .001).

Thermography is a suitable method to measure the inflammatory reaction related to third molar removal. Thermal changes are significant and are decreased by the nonsteroidal anti-inflammatory drug diclofenac.