Evaluation of the efficacy of transcutaneous electrical nerve stimulation (TENS) on salivary flow rate in patients with xerostomia - A case control study

Abstract

Introduction: In oral cavity, saliva is a physiological fluid present in the oral cavity. Oral fluid is an absolute media exploring for health and disease surveillance. Saliva is a complex fluid. Xerostomia is the subjective complain of dryness in the oral cavity due to decreased salivary flow. Transcutaneous electrical nerve stimulation (TENS) is an established physical therapy, which is useful for the pain relief.

Materials and methods: A total of 25 subjects of xerostomia and 25 age and sex matched normal subjects visiting the Department of Oral Medicine and Radiology, Pacific Dental College and Hospital were included in the study. For patients with positive mirror stick test unstimulated saliva were collected with 'low forced spitting' method in a graduated test tube for 5 minutes. Individuals with unstimulated salivary flow equal to or less than 0.5 mL per 5 min were included in the study group (xerostomia) and individuals with salivary flow more than 0.5 mL per 5 min were included in the control group (age and sex matched). The TENS unit were then activated and intensity control switch were gradually increased to tolerable level of patient for 15 min. At this optimal intensity, stimulated saliva were collected for 5 min with same method in a separate graduated test tube and flow rate were compared with unstimulated salivary flow rate. Same were done with 25 control patients.

Results: The data thus obtained was subjected to statistical analysis. The following findings were observed in the study. There was increase salivary flow rate in xerostomic individuals after TENS application. More improvement was found in inter appointment salivary flow than two follow-ups. Healthy group showed more improvement than xerostomia after TENS therapy Known cases of diabetes mellitus patients with xerostomia revealed more improvement than other etiologies of xerostomia included in this study.

Conclusion: This present study has an important therapeutic value in the treatment of patients with xerostomia. TENS therapy was highly effective in stimulating whole salivary flow. The encouraging results of this present study indicate that TENS has the potential to increase salivary flow rate and can be an important alternative in the xerostomia treatment.

Keywords: Saliva; Salivary flow rate; TENS; salivary glands; xerostomia.