Low-level laser treatment applied at auriculotherapy points to reduce postoperative pain in third molar surgery: A randomized, controlled, single-blinded study

Abstract

Objective: Evaluate the effectiveness of LLL (Low level laser therapy) in auriculotherapy points for pain reduction following lower third molar extractions.

Study design: Randomized, controlled, single-blinded study.

Methods: Eighty-four bilateral, symmetrical third molar surgeries were performed in 42 healthy patients using a split-mouth design. In the immediate postoperative period, each side was randomly treated in a single-blind method with an LLL at the auriculotherapy points or simulation of its use (contralateral side) over a 21-day interval. This protocol was repeated 24 and 48 hours after surgery. All patients used the same analgesic (paracetamol) but only in case of pain. The primary variable was postoperative pain according to the visual analogue scale, and the secondary variables were mouth opening, edema, local temperature, dysphagia, and the presence of infection (systemic temperature, lymphadenopathy). These variables were evaluated at baseline and at 24 hours, 48 hours and seven days after surgery. Adverse effects were recorded and reported.

Results: There was no difference between the groups in relation to any of the evaluated parameters (p>0.05).

Conclusion: For this experimental model, application of a low-intensity laser at auriculotherapy points did not prevent postoperative pain following lower third molar surgery.

Trial registration: This trial is registered at ClinicalTrials.gov; the registration number is NCT02657174 and the Unique Protocol ID number is 1.100.869. (https://register.clinicaltrials.gov/prs/app/template/EditRecord.vm?epmode=View&listmode=Edit&uid=U0002BEY&ts=11&sid=S0006026&cx=6g4wff).

Fig 1. Activity flowchart.

Fig 2. Auriculotherapy points.

1) Shen Men, 2) Sympathetic (SNV), 3) Stomach, 4) Toothache 3, 5) Jaw, 6) Adrenal.

Fig 3. Acupoint detector MH-II^®.

(A) patient hand probe (B) hand-piece for detection.

Fig 4. Postoperative pain data according to the visual analog scale (VAS) in both groups in all evaluation timepoints.

X axis—Pain was measured in centimeters (1–10 cm) by Visual Analogue Scale (VAS), Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 5. Presence of edema measured by the corner of the eye to angle of the jaw in the groups in all evaluation timepoints.

X axis–Edema was measured in centimeters (1–10 cm) by the corner of the eye to angle of the jaw, Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 6. Presence of edema measured by the Tragus to the labial commissure in the groups in all evaluation timepoints.

X axis–Edema was measured in centimeters (1–10 cm) by the (II) Tragus to the labial commissure, Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 7. Presence of edema measured by the Tragus to pogonion in the groups in all evaluation timepoints.

X axis–Edema was measured in centimeters (1–10 cm) by the (II) Tragus to the labial commissure, Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 8. Mouth opening measurement in both groups in the four observed timepoints.

X axis–Mouth opening was measured in centimeters (cm), Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 9. Intake of pain medication in both groups in the four observed timepoints.

X axis–medicines ingested in absolute numbers, Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 10. Temperature of operated side in both groups in the four observed timepoints.

X axis–Temperature of operated side was measured in degrees Celsius (^oC), Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 11. Temperature of opposite side in both groups in the four observed timepoints.

X axis–Temperature of opposite side was measured in degrees Celsius (^oC), Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 12. Systemic temperature in both groups in the four observed timepoints.

X axis–Sistemic Temperature was measured in degrees Celsius (^oC), Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.

Fig 13. Inflamed lynphonode in both groups in the four observed timepoints.

X axis–Number of inflamed lynphonodes, Y axis–measures were performed in baseline (0), 1, 2 and 7 days after surgery; (1)- placebo group, (2)- laser group.