Transcutaneous Electrical Nerve Stimulation (TENS) on hyposalivation induced by radiotherapy in the head and neck region: a preliminary study

Purpose: To verify the acute effect of clectrostimulation on the salivary flow of patients with hyposalivation. Methods: Uncontrolled clinical trial evaluating 15 patients with hyposalivation induced by radiotherapy (RT) used for head and neck cancer treatment. Mean age of the patients was 56.8 +/- 6.46 years. Males outnumbered females (73%). Transcutaneous Electrical Nerve Stimulation (TENS) was adjusted with 50HZ of frequency and 250 mu s of pulse width. Intensity was adjusted over a 20-minute period according to maximum tolerance. The electrodes were attached bilaterally on the region of the salivary glands. Evaluation of the salivary flow was performed through sialometry before and immediately after application of TENS. Results: The most prevalent region for RT was the oropharynx (80.0% of cases). The mean dose used in RT was 64.6 +/- 7.27 Gy. After TENS, salivary flow increased significantly (p = 0.0051) from 0.05 (0.00; 0.40) mL/min to 0.10 (0.07: 0.40) mL/min. The response to TENS was directly correlated with the intensity of the tolerated electric current (r = 0.553; p = 0.032) and the dose used in RT (r = -0.514; p = 0.050). Conclusion: TENS was able to increase the salivary flow rate of patients with RT-induced hyposalivation.