Is thermography useful for assessment of postoperative inflammation after surgical removal of mandibular third molars when methylprednisolone is administered and how does it correlate with patients' perception of swelling?

Purpose: To assess the differences in facial skin temperature after mandibular third molar removal when patients received methylprednisolone and placebo, respectively and to assess the correlation between patient-reported swelling using a visual analog scale (VAS) and facial skin temperature measured using thermography.

Patients And Methods: The study involved patients with 2 mandibular third molars with an indication for removal. The patients received either methylprednisolone or placebo in a randomized, crossover study design. Thermograms and the swelling VAS score were recorded 2 days after surgery. The outcome variable was the temperature difference (Δt) between the operated and control sides. A 2-sample t test analyzed the difference in Δt between the first and second operations. Spearman's rank correlation analysis was used to assess the correlation between the swelling VAS scores and the Δt.

Results: A total of 124 patients (67 males, 57 females, mean age 25 years) had both mandibular third molars removed on 2 separate occasions. No difference in Δt was found when methylprednisolone and placebo were given (P = .07). In addition, the correlation between the swelling VAS score and Δt was 0.30 (P = .001) and 0.09 (P = .3) after the first and second operation, respectively.

Conclusions: Thermography does not seem sensitive enough to detect differences in the inflammatory response when patients received methylprednisolone or placebo. The correlation between the Δt and patient-reported swelling was low (≤0.3).