Effect of Low Power Laser in Tooth Pain Modulation Caused by Irreversible Inflammation

Anxiety, pain and discomfort are common stressful situations that occur during the dentistry practice, especially in the urgency endodontic practice. Studies have concluded that low intensity laser therapy is effective in treating pain. However, most studies have reported the low intensity laser therapy in chronic pain, few studies have shown its application on acute pain and none have evaluated the low intensity laser´s analgesic effect in acute pain of the pulp inflammation. Since the pulp tissue has the peculiar characteristic to be surrounded by dentin, in acute pulpits, the inflammatory reaction is more complicated than usual. Furthermore, during the inflammatory process, sometimes anesthesia is not always completely effective. Thus, this present study aims to evaluate whether previous therapy with low intensity laser could, by its analgesic effect, promote greater comfort especially to this type of patient. 60 patients with acute pulpits pain will be selected to this study (randomized and double-blinded) and they will be divided in 4 groups:

Group 1 ( n=15) - Control Group; Group 2 (n=15) - Laser 1: 780 nanometers (nm); 40 milliwatts (mW); 4 seconds per point; 0.16 Joules/point; total irradiated points: 02; Group 3 (n=15) - Laser 2: 780nm; 40 mW; 40 seconds per point; 1.6 Joules/point, total irradiated points: 02; Group 4 (n=15) - Placebo group - Sham Laser Irradiation.

The pain will be evaluated by a visual analogue scale (VAS) in 3 different times: initial pain, pain immediately after and 15 minutes after interventions (laser irradiation, or sham laser irradiation). After that, patients with acute pulp irreversible inflammation will be submitted to conventional endodontic urgency treatment. Data concerning the need of complimentary local anesthesia will be also taken into account. Data of different groups and times will be statistically compared.