MAXIMUM PROTRUSIVE TONGUE FORCE IN HEALTHY YOUNG ADULTS.

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.

Métodos quantitativos para avaliação da força de língua / Quantitative methods for assessing tongue force

Por muitos anos, pesquisadores têm procurado métodos para quantificar a força da língua e muitos instrumentos foram construídos para este fim. O objetivo deste trabalho é apresentar uma revisão crítica da literatura sobre instrumentos para quantificar a força de língua. Os 30 aparelhos encontrados foram agrupados em quatro diferentes categorias: bocal contendo sensores (n=9), sensores fixados nos dentes, palato ou em placas palatais (n=8), bulbos preenchidos com fluidos e conectados a sensores de pressão (n=7) e outras tecnologias (n=8). Esses instrumentos podem, potencialmente, auxiliar o fonoaudiólogo na avaliação miofuncional orofacial, fazendo com que o diagnóstico de força da língua seja mais preciso. Alguns aparelhos apresentam desvantagens, tais como não serem sensíveis a pequenas mudanças de força, dificuldades na reprodutibilidade do posicionamento e outros pontos específicos. A grande variação de valores de força/pressão máxima e média encontrados relaciona-se à grande diversidade dos métodos, que empregam diferentes tecnologias.

For several years, researchers have been looking for methods to quantify tongue force and a lot of devices were constructed for this purpose. The purpose of this study is to present a critical literature review about the devices to quantify tongue strength. Thirty devices were found. They were grouped into four different categories: mouthpiece containing sensors (n=9), sensors attached on teeth surface or on palatal plates (n=8), bulbs filled with some fluid and connected to a pressure sensor (n=7) and other technologies (n=8). These methods can, potentially, help speech-language pathologists in the orofacial myology evaluation, making the diagnosis of tongue force more reliable. Some of them present disadvantages such as not being sensitive enough to small changes in force, difficulties in positioning reproducibility and other specific points. The large variation in maximum and average strength/pressure values are related to the large diversity of the methods, which use different technologies.

Quantitative evaluation of tongue protrusion force.

The tongue plays an important role in the functions of speech, mastication, swallowing, and breathing. The tongue helps in the maintenance of proper dental alignment and arch stability. Adequate strength is essential for the tongue to perform these tasks. Recently the Biomechanical Engineering Group from Universidade Federal de Minas Gerais, Brazil, developed a device to improve tongue strength evaluation. The purpose of this study is to describe and compare the main results obtained in tongue protrusion force measurements in different age groups using this new device. Fifteen healthy subjects were given a qualitative evaluation and determined to have normal tongue strength. They were separated by age in three groups: children, adults and elderly. They were then given a quantitative evaluation. Maximum and average forces were analyzed. The time taken to reach maximum force was also assessed. Higher values of maximum and average tongue force were obtained in the adult group, followed by the elderly group and the group of children. Older subjects had greater tongue force when compared to children. However, there were statistically significant differences in the average force and in the maximum force only between children and adults. Time taken to reach maximal isometric force was longer in the elderly group and shorter in the group of children than in the group of adults although no statistically significant difference was found between groups.