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Summary Background Lingual exercises are commonly used in clinical practice for swallowing rehabilitation. Associating lingual exercises with computer games increases motivation, which influences tongue motor performance. Objective To investigate the effects of tongue movement direction; resistance force level; repetition number; sustained tongue contraction duration; age and gender on tongue motor performance in healthy adults using computer games. Methods An observational pilot study was carried out at a university laboratory. Nine healthy adults, aged 22 to 38 years, used an intra‐oral joystick controlled by the tongue to play four computer games. The participants had to reach 12 targets that appeared on the computer screen using the intra‐oral joystick. Motor performance was measured by the number of attempts to score and the time during which the target force was maintained. Tongue motor performance was compared among tongue movement direction, resistance force level, game round number, and continuous force application time on the target, age and gender. Results The number of attempts depended significantly on the direction, continuous force application time on the target and age. The time during which the target force was maintained depended significantly on the direction, continuous force application time on the target and game round number. There were no significant differences in the comparisons by gender or by resistance force level. Conclusions It was seen that young adults had their best performance in the downward direction, on the third round, holding the force for a shorter time. The performance deteriorated as age increased.

The findings indicated diversity in methodologies; 14/15 articles reviewed were limited to the evaluation of the topography of the posterior back. A study, using two-dimensional photogrammetry, presented a whole body postural evaluation. As the asymmetry in AIS can be extended to the whole body, more attention should be given to develop full body assessment techniques to provide important additional data to aid in treatment decisions.

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Thermo-mechanical finite element analyses in 3-D models are described for determination of the stress levels due to thermal and mechanical loads in a healthy and restored tooth. Transient thermo-mechanical analysis simulating the ingestion of cold and hot drinks was performed to determine the temperature distribution in the models of the teeth, followed by linear elastic stress analyses. The thermal loads were applied on the occlusal and lingual surfaces. Subsequently, coupled variation of the temperature and mastication loading was considered. The vertical loading was distributed at occlusal points, adding up to 180 N. Maximum stresses were verified in resin restoration under thermal loads. When studying coupled effect of mechanical loading with that arising from thermal effects, higher tensile stress values occurred in porcelain restorations, especially at the restoration-dentin interface. Regions of high tensile stress were detected and their possible clinical significance with respect to restoration damage and microleakage were discussed.

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OBJETIVO: Quantificar e comparar as forças produzidas pela língua de crianças respiradoras orais pré-cirúrgicas, respiradoras orais em tratamento fonoaudiológico e respiradoras nasais, além de comparar os achados da avaliação objetiva com os dados da avaliação clínica. MÉTODOS: Estudo transversal com 15 crianças, de ambos os gêneros, com idades entre oito e 12 anos, sendo cinco respiradoras orais pré-cirúrgicas (Grupo 1), cinco respiradoras orais em tratamento fonoaudiológico (Grupo 2) e cinco respiradoras nasais (Grupo 3). Foi realizada uma avaliação clínica das características linguais das crianças e, em seguida, uma avaliação objetiva da força axial da língua por meio de equipamento desenvolvido na Universidade Federal de Minas Gerais. Os resultados foram analisados de forma descritiva por meio das medidas de tendência central e dispersão. RESULTADOS: A média dos valores das forças médias encontrada nos Grupos 1, 2 e 3, respectivamente, foi de 5,6, 6,0 e 7,3N. Já a média dos valores de força máxima foi de 8,2, 9,2 e 10,4N. Obtiveram os maiores valores de força média (7,0N) e máxima (10,3N) os indivíduos que apresentaram tensão adequada de língua na avaliação clínica e os valores mais baixos (3,5N e 2,0N) aqueles cuja avaliação subjetiva indicou hipotensão lingual. A análise estatística indicou dados heterogêneos nos Grupos 1 e 2, tendendo a homogêneos no Grupo 1. CONCLUSÕES: A média das forças foi maior nos indivíduos respiradores nasais, seguidos pelos respiradores orais em tratamento fonoaudiológico e, por fim, os respiradores orais pré-cirúrgicos. Houve concordância entre os resultados das avaliações objetiva e clínica.

This work discusses the effect of enamel anisotropy in the stress concentration at the cement-enamel junction (CEJ), a probable cause of fracture in enamel leading to abfraction. Usual simplifications when developing computer models in dentistry are to consider enamel isotropic, or that the direction of the prisms is orthogonal to either the dentine-enamel interface or the tooth outer surface. In this paper, a more refined model for the material behavior is described, based on laboratory observation and on the work of Fernandes and Chevitarese. The material description is used in a two-dimensional (2D) finite element model of the first upper premolar, and the analysis is performed for two different situations: vertical loads, typical of normal mastication and horizontal loads, dominant in bruxism. The analyses were performed using a unit load, which under the hypothesis of linear response of the tooth, allows the combinations described in the text to simulate different functional and parafunctional loads. The results indicate that a realistic enamel description in terms of mechanical properties and spatial distribution of its prisms alters significantly the resulting stress distribution. For all cases included in this study, the detailed description of prism orientation and resulting anisotropy led to improved response in terms of stress distribution, even when loading was horizontal.