Hyposalivation is a frequent complication after treatment with radiotherapy. To evaluate the efficacy of transcutaneous electrical nerve stimulation (TENS) on the hyposalivation assessed through stimulated salivary flow (SSF). In this clinical trial, 68 patients (with hyposalivation) were randomly assigned to control (n = 31) or TENS (n = 37) group. Participants in control group received habitual care, while those in TENS group received 8 sessions (20 minutes each) delivered twice a week for four weeks. The electrodes were attached over the skin covering the salivary glands. The electric pulse was adjusted at a frequency of 50 Hz, pulse width of 250 μs and as intense as tolerated. SSF was evaluated through sialometry. Self‐perception of salivary flow (SPSF) and quality of life (QL) was evaluated prior to, during and at 1, 3 and 6 months after treatment. Although no changes were observed in the control group for SSF at any timepoints, TENS group showed a progressive increase in SSF from the third session until the end of the treatment. Significant improvements were also found in SPSF, especially when the SSF reached values ≥0.7 mL/minute. The most expressive results were evident at 6 months after treatment so that SSF, SPSF and QL remained significantly higher (F = 9.5, P = 0.0001; H = 143.77, P < 0.0001; χ2 = 9.162, P = 0.02, respectively). TENS was effective at improving hyposalivation. The benefits on SSF, SPSF and QL give base to a promising therapeutic strategy for patients with hyposalivation after radiotherapy treating head and neck cancer.

At rest, the lip exerts a larger force than the tongue on the maxillary right central incisor tooth. During swallowing, there was no difference between lip and tongue force on the tooth.

TENS was able to increase the salivary flow rate of patients with RT-induced hyposalivation.

RESUMO Objetivo Analisar os efeitos da eletroestimulação sobre o fluxo salivar de pacientes com hipossalivação induzida por radioterapia em região de cabeça e pescoço. Estratégia de pesquisa Utilizaram-se as bases de dados Medline (via Pubmed), Cochrane Library, Scopus e Lilacs. Critérios de seleção Foram selecionados os ensaios clínicos que avaliaram objetivamente o fluxo salivar, publicados nos últimos 10 anos em português, inglês ou espanhol. Análise dos dados Para avaliação metodológica dos estudos, foi utilizada a escala PEDro. Resultados A estratégia de busca resultou em 21 publicações, sendo que 17 foram excluídas, selecionando-se assim 4 artigos. Os estudos incluídos contaram com um total de 212 participantes, sendo que todos demonstraram aumento do fluxo salivar, tanto por meio do método de eletroacupuntura quanto pela estimulação aplicada diretamente sobre as glândulas salivares. A pontuação obtida por meio da escala PEDro foi baixa, evidenciando qualidade metodológica baixa e com consideráveis riscos de viés. Conclusão os estudos incluídos demonstram o potencial clínico da TENS no aumento do fluxo salivar de pacientes com câncer de cabeça e pescoço tratados com RT.

In clinical speech-language pathology practice, tongue force is usually evaluated qualitatively. Perception and practical experience are used to classify this force. The Biomechanical Engineering Group from the Federal University of Minas Gerais developed an instrument to quantify tongue force. The purposes of this study were to quantify maximum tongue protrusion force in Brazilian subjects with normal tongue strength and to compare force values between gender groups. In total, 105 subjects, 43 men and 62 women, aged from 18 to 29 years, with normal tongue strength according to qualitative evaluation, underwent quantitative evaluation by using the instrument. The mean of the maximum tongue force values of all participants was 17.58±7.95 N. There were significant differences in the median values for maximum tongue forces between the genders, with higher values observed for men. In intersubject comparisons, high variation coefficients were evident due to the variability among individuals. However, the study suggested that the instrument could be an interesting tool for intrasubject comparisons, especially during the follow-up.