Determination of Micromovements in Removable Prosthesis during Mastication: A Pilot Study with 3D Electromagnetic Articulography.

Edentulism can generate negative impacts on self-esteem, interpersonal relationships, and oral functions. Removable prostheses are commonly used for tooth replacement, but they may cause discomfort due to micromovements during mastication. Objective and quantifiable methods are needed to evaluate these micromovements. A pilot study was conducted to determine the micromovements in removable prostheses during mastication using a 3D electromagnetic articulography (EMA-3D) system. One elderly participant wearing lower removable prostheses and an upper total well-fitting removable prosthesis was studied. The EMA-3D system was used to record movements in three spatial planes. Peanuts were given as test food, and the participant was instructed to chew normally while recordings were carried out until feeling the need to swallow. Analyses of the upper total prosthesis show micromovements ranging from 0.63 ± 0.11 to 1.02 ± 0.13 mm. During simultaneous analyses of the upper prosthesis and lower partial prosthesis, interference was not observed. This pilot study demonstrated the feasibility of using the EMA-3D system to evaluate micromovements in removable prostheses during mastication. Further research is needed to evaluate a larger sample and assess the clinical implications of these micromovements.

Chewing Analysis by Means of Electromagnetic Articulography: Current Developments and New Possibilities.

Chewing is a complex procedure that involves sensory feedback and motor impulses controlled by the trigeminal system in the brainstem. The analysis of mandibular movement is a first approximation to understanding these mechanisms. Several recording methods have been tested to achieve this. Video, ultrasound, the use of external markers and kinesiographs are examples of recording systems used in research. Electromagnetic articulography is an alternative method to those previously mentioned. It consists of the use of electromagnetic fields and receiver coils. The receiver coils are placed on the points of interest and the 3D coordinates of movement are saved in binary files. In the Oral Physiology Laboratory of the Dental Sciences Research Center (Centro de Investigación en Ciencias Odontológicas-CICO), in the Faculty of Dentistry at the Universidad de La Frontera (Temuco, Chile) several research studies have been carried out using the AG501 3D EMA articulograph (Carstens Medizinelektronik, Lenglern, Germany). With this device, they developed a series of protocols to record mandibular movement and obtain new information, such as the 3D Posselt polygon, the area of each polygon, individualized masticatory cycles and speed and acceleration profiles. Other investigations have analyzed these parameters, but separately. The AG501 allows for holistic analysis of all these data without altering natural movement. A limitation of this technology is the interference generated by its metallic elements. The aim of the present work is to show the developed methods used to record mandibular movement in the CICO, using the AG501 and compare them with others used in several research studies.

Actualización del análisis de los movimientos mandibulares a través de articulografía electromagnética / Updating the analysis of mandibular movements through electromagnetic articulography

El objetivo de registrar los movimientos mandibulares es obtener parámetros relevantes que permitan evaluar el estado de la articulación temporomandibular (ATM) y de los músculos involucrados en la masticación. El movimiento mandibular se debe a un conjunto complejo de rotaciones y traslaciones tridimensionales realizadas por la ATM, limitado por los ligamentos y las superficies articulares de estas, y por la morfología y la alineación de los dientes, cuando la mandíbula se desplaza sobre estos límites, se llaman movimientos bordeantes mandibulares. El objetivo de este artículo es realizar una descripción actualizada de los movimientos mandibulares a través de articulografía electromagnética. Los movimientos mandibulares bordeantes se clasifican según el plano del espacio en que se muevan, de esta manera tenemos movimientos bordeantes en el plano sagital, en el plano horizontal y el plano frontal, y en cada plano dibujan un polígono distinto, llamados polígonos de Posselt. Estos polígonos pueden ser registrados mediante Articulografía electromagnética, gracias a esta tecnología también se pueden extraer algunos parámetros interesantes, como por ejemplo: la trayectoria total recorrida por la mandíbula al describir cada polígono, rangos de desplazamiento en cada plano, área total de cada polígono de Posselt. La apertura mandibular se mide como la distancia entre los márgenes incisales de los incisivos centrales superiores e inferiores en apertura máxima más la sobremordida. El análisis de esta es una parte importante del examen clínico en odontología, ya que una apertura limitada puede ser resultado de trastornos en la articulación temporomandibular, fibrosis oral submucosa, enfermedad reumática o trauma facial. Las mediciones tridimensionales que se obtienen gracias a la Articulografía electromagnética, son apropiados para determinar los rangos normales de apertura, su exactitud permite la realización de investigaciones en el área, abriendo un amplio campo en el análisis de los movimientos mandibulares.

SUMMARY: The objective of recording mandibular movements is to obtain relevant parameters that allow the evaluation of the state of the temporomandibular joint (TMJ) and of the muscles involved in mastication. Mandibular movement is due to a complex set of three-dimensional rotations and translations performed by the TMJ, limited by the ligaments and their articular surfaces, and by the morphology and alignment of the teeth, when the mandible moves over these limits, they are called mandibular border movements. The aim of this article is to provide an updated description of mandibular movements through electromagnetic articulography. Mandibular border movements are classified according to the plane of space in which they move, thus we have border movements in the sagittal plane, in the horizontal plane and the frontal plane, and in each plane they draw a different polygon, called Posselt polygons. These polygons can be recorded by electromagnetic articulography, thanks to this technology some interesting parameters can also be extracted, such as: the total trajectory covered by the mandible when describing each polygon, displacement ranges in each plane, total area of each polygon of Posselt. Mandibular opening is measured as the distance between the incisal edges of the upper and lower central incisors at maximum opening plus the overbite. The analysis of mandibular opening is an important part of the clinical examination in dentistry as a preliminary evaluation, since limited opening can be the result of temporomandibular joint disorders, submucous oral fibrosis, rheumatic disease or facial trauma. The three-dimensional measurements that are obtained thanks to the electromagnetic Articulography, are appropriate to determine the normal ranges of opening, its accuracy allows the realization of investigations in the area, opening a wide field in the analysis of mandibular movements. Analysis of mandibular opening is an important part of the clinical examination in dentistry, since limited opening can be the result of temporomandibular joint disorders, oral submucous fibrosis, rheumatic disease, or facial trauma. Analysis of mandibular opening is an important part of the clinical examination in dentistry, since limited opening can be the result of temporomandibular joint disorders, oral submucous fibrosis, rheumatic disease, or facial trauma. The three-dimensional measurements that are obtained thanks to the electromagnetic Articulography, are appropriate to determine the normal ranges of opening, its accuracy allows the realization of investigations in the area, opening a wide field in the analysis of mandibular movements.

A Novel Technique to Accurately Measure Mouth Opening Using 3D Electromagnetic Articulography.

The mouth opening is an important indication of the functionality of the temporomandibular joint (TMJ). Mouth opening is usually evaluated by asking the patient to open their mouth as wide as possible and measuring the distance between the edges of the frontal incisors with a ruler or caliper. With the advancement of technology, new techniques have been proposed to record mandibular movement. The aim of this work is to present a novel technique based on 3D electromagnetic articulography and data postprocessing to analyze the mouth opening considering distances, trajectories, and angles. A maxilla-mandible phantom was used to simulate the mouth opening movement and fixed position mouth opening. This was recorded using the AG501 3D EMA (Carstens Medizinelektronik GmbH, Bovenden, Germany). The collected data was processed using Matlab (Mathworks, Natick, MA, USA). Fix and mobile mouth opening of 1, 2, 3 and 4 cm were simulated. It was possible to evaluate the mandibular opening through the vertical distance, the Euclidean distance, the trajectory, and the opening angle. All these values were calculated and the results were consistent with expectations. The trajectory was the highest value obtained while the vertical distance was the lowest. The angle increased as the mouth opening increased. This new technique opens up new possibilities in future research since oral opening can be analyzed using multiple variables without the need to use different devices or depending on the researcher's experience. This will make it possible to establish which parameter presents significant differences between groups of patients or between patients who have undergone some treatment.

Dimensión vertical de la cara en adultos con diferentes relaciones oclusales / Vertical dimension of face in adults with different Angle class

RESUMEN: Se ha postulado que la posición postural mandibular (PPM) no presentaría la menor actividad electromiográfica (EMG) de los músculos masetero y temporal, y que esta menor actividad se encontraría en una apertura mayor. El objetivo de este estudio fue analizar la PPM en pacientes con diferentes relaciones oclusales y según tipo de método de posicionamiento, relacionándolo con la actividad EMG de los músculos Masetero y Temporal, además del registro de la actividad EMG en diferentes aperturas orales. Se analizó una muestra de 25 adultos de 18 a 28 años. Estos fueron clasificados según su sexo y clasificación de Angle. Se realizaron simultáneamente registros de EMG de superficie -masetero y porción anterior del temporal- y de EMA -posición de la mandíbula respecto al maxilar obteniendo distancia y ángulo- en diferentes posiciones mandibulares: PPM-considerando método sin comando y de deglución- y apertura gradual hasta alcanzar la máxima apertura. Se realizó un análisis estadístico descriptivo. La menor PPM obtenida fue de 1,0 ± 0,6 mm en mujeres Clase III y utilizando la técnica sin comando; el mayor fue de 2,5 ± 0,2 mm en mujeres Clase II y utilizando la técnica de deglución. La apertura angular presentó menor variabilidad que las distancias lineales. La actividad de los músculos Maseteros derecho e izquierdo presentaron valores similares entre sí, al igual que en los rangos de apertura hasta 30 mm en hombres y mujeres y en las diferentes relaciones oclusales. La actividad de los Temporales para hombres y mujeres y en las diferentes relaciones oclusales mostraron variaciones importantes entre derecha e izquierda y en los diferentes grados de apertura. La técnica presentada permitió el estudio de la dimensión vertical y aperturas orales a través de EMA y EMG.

SUMMARY: It has been postulated that the mandibular postural position (MPP) could not present the lower electromyographic activity (EMG) of the Masseter and Temporal muscles, and that the lower activity could be found in a larger opening. The objective of this study was to analyze the PPM in patients with different occlusal relationships and according to the positioning method, relating it to the EMG activity of the Masseter and Temporal muscles, in addition to recording the EMG activity in different oral openings. A sample of 25 adults aged 18 to 28 years was analyzed. Participants were classified according to their sex and Angle classification. Simultaneous recordings of surface EMG -Masseter and anterior portion of the Temporal- and EMA -position of the Mandible with respect to the Maxilla obtaining distance and angle- were performed in different mandibular positions: PPM-considering the method "without command" and "swallowing"- and gradual opening until the maximum opening is reached. A descriptive statistical analysis was performed. The lowest PPM obtained was 1.0 ± 0.6 mm in Class III women and using the "without command" method; the largest was 2.5 ± 0.2 mm in Class II women and using the "swallowing" method. The angular opening presented less variability than the linear distances. The activity of the right and left masseter muscles presented similar values, as well as in the opening ranges up to 30 mm in men and women and in the different occlusal relationships. The activity of the Temporals for men and women and in the different occlusal relationships showed important variations between right and left and in the different degrees of opening. The presented technique allowed the study of the vertical dimension and oral openings through EMA and EMG.

Oral configurations during vowel nasalization in English.

Speech nasalization is achieved primarily through the opening and closing of the velopharyngeal port. However, the resultant acoustic features can also be influenced by tongue configuration. Although vowel nasalization is not contrastive in English, two previous studies have found possible differences in the oral articulation of nasal and oral vowel productions, albeit with inconsistent results. In an attempt to further understand the conflicting findings, we evaluated the oral kinematics of nasalized and non-nasalized vowels in a cohort of both male and female American English speakers via electromagnetic articulography. Tongue body and lip positions were captured during vowels produced in nasal and oral contexts (e.g., /mɑm/, /bɑb/). Large contrasts were seen in all participants between tongue position of /æ/ in oral and nasal contexts, in which tongue positions were higher and more forward during /mæm/ than /bæb/. Lip aperture was smaller in a nasal context for /æ/. Lip protrusion was not different between vowels in oral and nasal contexts. Smaller contrasts in tongue and lip position were seen for vowels /ɑ, i, u/; this is consistent with biomechanical accounts of vowel production that suggest that /i, u/ are particularly constrained, whereas /æ/ has fewer biomechanical constraints, allowing for more flexibility for articulatory differences in different contexts. Thus we conclude that speakers of American English do indeed use different oral configurations for vowels that are in nasal and oral contexts, despite vowel nasalization being non-contrastive. This effect was consistent across speakers for only one vowel, perhaps accounting for previously-conflicting results.

Análisis cinemático de la masticación de alimentos duros y blandos en participantes dentados utilizando articulografía electromagnética 3D / Kinematic analysis of hard and soft food mastication in dentate participants using 3D electromagnetic articulography

RESUMEN: Diversos estudios reportan que el tipo de alimento influye directamente en los patrones cinemáticos de la masticación. El objetivo de este estudio fue analizar y comparar los ciclos masticatorios de participantes adultos y completamente dentados durante la masticación de alimentos de diferente textura y dureza (maní y zanahoria) utilizando articulografía electromagnética 3D. Se evaluaron 11 participantes sanos (5 hombres; 6 mujeres), de 31,9 ± 5,2 años de edad. Mediante articulografía electromagnética 3D, se registró la masticación de dos alimentos de prueba (maní y zanahoria). Los datos de movimiento mandibular fueron procesados con MATLAB® y obteniendo diferentes parámetros-frecuencia masticatoria en ciclos por segundo, velocidad de descenso y ascenso mandibular, área de las proyecciones de cada ciclo masticatorio en los tres planos del espacio-que fueron comparados según tipo de alimento y género de los participantes. Se encontraron diferencias estadísticamente significativas entre las áreas de los ciclos masticatorios en el plano horizontal según tipo de alimento, siendo mayor para la masticación de zanahoria (P=,003). Así mismo, se detectaron diferencias estadísticamente significativas entre las áreas sagitales de los ciclos entre hombres y mujeres, siendo mayor en mujeres (P=,042). Nuestros resultados concuerdan con otros estudios que afirman que la textura del alimento influye en las características cinemáticas de los ciclos masticatorios.

SUMMARY: Several studies report that the type of food directly influences the kinematic patterns of mastication. The aim of this study was to analyze and compare the chewing cycles of adult and fully dentate participants during the mastication of foods of different texture and hardness (peanuts and carrots) using 3D electromagnetic articulography. Eleven healthy participants (5 men; 6 women), 31.9 ± 5.2 years old, were evaluated. By means of 3D electromagnetic articulography, the mastication of two test foods (peanuts and carrots) was recorded. The data associated to mandibular movement were processed with MATLAB® obtaining different parameters-masticatory frequency in cycles per second, mandibular descent and ascent rate, area of the projections of each masticatory cycle in the three planes of space-which were compared according to type of food and sex of the participants. Statistically significant differences were found between the areas of the masticatory cycles in the horizontal plane according to type of food, being greater for carrots (P=.003). Likewise, statistically significant differences were detected between the sagittal areas of the cycles between men and women, being greater in women (P=.042). Our results agree with other studies that affirm that the texture of the food influences the kinematic characteristics of the masticatory cycles.

Biomechanical Biomarkers of Tongue Impairment During Swallowing in Persons Diagnosed with Amyotrophic Lateral Sclerosis.

BACKGROUND: The impact of tongue dysfunction on deglutition in persons diagnosed with amyotrophic lateral sclerosis (ALS) is not well understood. This information is needed to improve our understanding of the mechanisms of swallowing impairment, for identifying risk factors of dysphagia, and for establishing impairment-specific treatments aimed at slowing the loss of swallow function. OBJECTIVES: The goals of this study were to determine the relation between biomechanical measures of oral tongue movements using electromagnetic articulography (EMA) and measures of swallow physiology, swallow safety and efficiency, and self-reported swallowing function. METHODS: Participants were diagnosed with ALS by a neurologist following the El Escorial Criteria from the World Federation of Neurology. Twelve participants underwent (1) EMA to derive biomechanical measures of the tongue, (2) videofluoroscopic evaluation to measure swallow physiology, safety, and efficiency, and (3) maximal tongue strength testing using the Iowa Oral Pressure Instrument (IOPI). Participants completed self-reported functional assessments. Spearman's rank correlations assessed for associations between lingual biomechanics and swallowing physiology, swallow safety and efficiency, and self-reported bulbar function. RESULTS: Results demonstrated strong associations between biomechanical and swallowing physiology, swallow safety, and self-reported measures. Notably, swallowing safety during thin liquid intake was associated with tongue speed (r = - 0.7, p < 0.05) and range of motion (r = - 0.71, p < 0.05), and swallowing safety during puree intake was associated with tongue strength (r = - 0.69, p < 0.05). CONCLUSIONS: Our findings underscore the importance of tongue movements on swallowing physiology and safety, help improve our understanding of mechanisms of swallowing impairment, and highlight a potential clinical tool to index bulbar impairment.

Accuracy and Reliability of AG501 Articulograph for Mandibular Movement Analysis: A Quantitative Descriptive Study.

Electromagnetic articulography (EMA) have been mostly employed to study articulatory movements of speech. This technology appears to be very promising for studying mandibular movements within the field of dentistry. However, there are no studies reporting the validity of EMA for such purpose. The aim of this study is to assess accuracy and reliability of Carstens three-dimensional EMA AG501 in order to validate its use for mandibular movement analysis in dentistry. A set of tests was conducted attaching 16 sensors to a rotating rigid structure placed inside the measurement area. Another set of tests were conducted using a mouth anatomical model with human-like articulatory behaviour. A function of the EMA system called "head correction" was applied to normalize the data of every recording. The system reliability was higher at the centre of the measurement area and decreased toward the edges. Dispersion was greater for raw data than for normalized data. Bland-Altman analysis of agreement between the AG501 and a millimetre ruler used to measure the distance between the sensors revealed limits of agreement between 0.5 mm and -0.9 mm. The results suggest that EMA AG501 is valid for three-dimensional analysis of mandibular biomechanics allowing natural movements.

Coordination between lingual motion and pressure production during dipper/tipper type swallows.

BACKGROUND: Tongue motor biomechanics during swallowing was not fully elucidated due to the technical difficulty. OBJECTIVE: To evaluate the relationship between tongue motion and tongue pressure production by simultaneously measuring tongue motion and tongue pressure during water swallowing. METHODS: In 12 healthy male participants (mean age, 30.8 ± 4.2 years), tongue pressure and tongue motion trajectory during dipper- and tipper-type swallows of 3 mL of water were measured using a sensor sheet system equipped with five sensing points and an electromagnetic articulography, respectively. The temporal correlation between motion of anterior/posterior tongue and tongue pressure production during swallowing was evaluated on the synchronised waveforms. RESULTS: In the dipper-type swallow, a similar up-and-down motion pattern in vertical direction was observed among all participants before tongue pressure production. Those motion patterns were common at the anterior and posterior tongue locations with a temporal difference in some segment of tongue motion. On the other hand, tongue directly attached to hard palate with temporal synchronicity between the anterior and posterior parts. In both types of swallow, a strong temporal correlation was found between the timing of tongue-palate contact and the Onset of tongue pressure by intra-class correlation coefficients. CONCLUSION: From the simultaneous measurement of tongue motion and tongue pressure production, the tongue motion pattern during water swallowing and the temporal correlation between tongue motion and tongue pressure production were elucidated.

Description of acoustic and articulatory parameters of vowels in mapudungun speakers: pilot study / Descripción de parámetros acusticos y articulatorios de las vocales en hablantes de mapudungun: estudio piloto

Mapudungun is a language used by Mapuche people in some regions of Chile and Argentina. The aim of this study was to describe the vowel phonemes with regard to the articulatory parameters (position of the tongue with respect to the palate and jaw opening) and acoustic parameters (f0, F1, F2 and F3) in Mapudungun speakers in the Region of La Araucanía. The vocalic phonemes of Mapudungun are six, where the first five are similar to those used in Spanish (/a e i o u/), to which is added a sixth vowel (/ɨ/) with its vocalic allophones (/ɨ/) and [Ә]. Three Mapudungun speakers were evaluated. The tongue movements were collected by Electromagnetic Articulography 3D and the data were processed with MATLAB and PRAAT software. It was possible to describe the trajectory of each third of the tongue during the production of the vowels. It was observed that the sixth vowel /Ә/ had minimal jaw opening during its pronunciation. In addition, the characteristic of /Ә/ as an unrounded mid-central vowel was corroborated. In this study, the tongue of mapudungun speakers was in a more posterior position than the found in other studies.

El Mapudungun es un lenguaje utilizado por los mapuches en algunas regiones de Chile y Argentina. El objetivo de este estudio fue describir los fonemas vocálicos respecto a los parámetros articulatorios (posición de la lengua respecto al paladar y apertura mandibular) y los parámetros acústicos (f0, F1, F2 y F3) en hablantes de Mapudungun en la Región de La Araucanía, los fonemas vocálicos de Mapudungun son seis, donde los primeros cinco son similares a los utilizados en español (/a e i o u /), a los que se agrega una sexta vocal (/ɨ/) con sus alófonos vocálicos [ɨ] y [Ә]. Se evaluaron tres hablantes de Mapudungun. Los movimientos de la lengua fueron registrados por Articulografía Electromagnética 3D y los datos fueron procesados con el software MATLAB y PRAAT. Fue posible describir la trayectoria de cada tercio de la lengua durante la producción de las vocales. Se observó que la sexta vocal /Ә/ tenía una apertura mínima de la mandíbula durante su pronunciación. Además, se corroboró la característica de /Ә/ como vocal central media no redondeada. En este estudio, la lengua de los hablantes de mapudungun estaba en una posición más posterior que la encontrada en otros estudios.

A two-case study of coarticulation in stuttered speech. An articulatory approach.

This study aims to describe the coarticulatory behaviour in stuttered speech from an articulatory point of view. Its purpose is to assess the nature of transitions between a stuttered phone and preceding and subsequent phones. Two persons who stutter were recorded by means of an electromagnetic articulograph while reading a text. The vertical movements of upper and lower lips, tongue body, tongue tip and mandible were extracted. They were then analysed during a stuttering moment and linked to the acoustic type of disfluency. Our findings showed several configurations of coarticulatory behaviour in terms of supraglottic articulatory movements. While disfluencies can be the result of a disrupted coarticulatory configuration, no systematicity has been found. Moreover, all acoustic types of disfluencies are represented in several coarticulatory configurations. Therefore, a stuttering-like disfluency is not always due to a coarticulatory disturbance, since correct coarticulatory patterns can be observed both between the disfluent sound and its previous and subsequent sounds. Furthermore, they suggest that the acoustic classification of disfluencies does not seem important for the coarticulatory behaviour.

Spatially Conditioned Speech Timing: Evidence and Implications.

Patterns of relative timing between consonants and vowels appear to be conditioned in part by phonological structure, such as syllables, a finding captured naturally by the two-level feedforward model of Articulatory Phonology (AP). In AP, phonological form - gestures and the coordination relations between them - receive an invariant description at the inter-gestural level. The inter-articulator level actuates gestures, receiving activation from the inter-gestural level and resolving competing demands on articulators. Within this architecture, the inter-gestural level is blind to the location of articulators in space. A key prediction is that intergestural timing is stable across variation in the spatial position of articulators. We tested this prediction by conducting an Electromagnetic Articulography (EMA) study of Mandarin speakers producing CV monosyllables, consisting of labial consonants and back vowels in isolation. Across observed variation in the spatial position of the tongue body before each syllable, we investigated whether inter-gestural timing between the lips, for the consonant, and the tongue body, for the vowel, remained stable, as is predicted by feedforward control, or whether timing varied with the spatial position of the tongue at the onset of movement. Results indicated a correlation between the initial position of the tongue gesture for the vowel and C-V timing, indicating that inter-gestural timing is sensitive to the position of the articulators, possibly relying on somatosensory feedback. Implications of these results and possible accounts within the Articulatory Phonology framework are discussed.

Relación entre Síntomas de Trastornos Témporomandibulares Auto-Reportados y el Movimiento Mandibular de Sujetos Adultos Jóvenes / Relationship Between Symptoms of Self-Reported Temporomandibular Disorders and Mandibular Movement of Young Adult Subjects

RESUMEN: Tanto la limitación del movimiento mandibular como el auto reporte de síntomas de trastornos témporomandibulares (TTM) son utilizados como elementos para el diagnóstico de pacientes en la clínica. Sin embargo, la relación entre la presencia de síntomas y el movimiento mandibular no está del todo clara. Por ello, el objetivo de este estudio fue relacionar la presencia de síntomas asociados a TTM con el movimiento mandibular en una muestra de sujetos adultos jóvenes y sanos. En este estudio exploratorio participaron 40 estudiantes de Odontología, médicamente sanos, con arco dentario maxilar y mandibular continuo y completo (hasta el primer molar). A cada uno se les solicitó responder un cuestionario de auto-reporte de síntomas asociados a TTM recomendado por la American Academy of Orofacial Pain (AAOP). También se realizó un registro y análisis de sus movimientos mandibulares utilizando articulografía electromagnética 3D, con el objetivo de correlacionar la presencia de síntomas con el rango y trayectoria de apertura, y el área comprendida en lo que se describe como polígono de Posselt en el plano frontal y sagital. No se encontraron diferencias significativas entre las respuestas a cada pregunta entre hombres y mujeres. De acuerdo a las respuestas y según Delcanho (1994), 12 participantes resultaron necesitar una evaluación más exhaustiva. En este grupo se encontró que el área del polígono de Posselt en el plano frontal, fue significativamente menor que el de aquellos participantes que no requieren una evaluación más exhaustiva (p=0,003). Los valores de la trayectoria de apertura mandibular varían según de que síntoma se trate. Los principales síntomas que afectarían los valores de los movimientos bordeantes son la "dificultad para abrir la boca" y el "ruido en las articulaciones mandibulares". Con este estudio, hemos puesto de manifiesto que la limitación del movimiento mandibular como signo de TTM debe evaluarse con cautela, debido a que según la presencia de determinados síntomas y otras características de los sujetos (como el sexo), su valor podría variar.

ABSTRACT: Both the limitation of mandibular movement and the self-report of symptoms of temporomandibular disorders (TMD) are used for the diagnosis of patients in clinical diagnosis. However, the relationship between the symptoms and mandibular movement is not entirely clear. Therefore, the objective of this study was to relate the presence of symptoms associated with TMD with mandibular movement in a sample of young and healthy adult subjects. This exploratory study involved 40 medically healthy dentistry students with a continuous and complete maxillary and mandibular arch (up to the first molar). Each subject was asked to answer a self-report questionnaire for symptoms associated with TTM recommended by the American Academy of Orofacial Pain (AAOP). We also recorded and analyzed their mandibular movements using 3D electromagnetic articulography, with the aim of correlating the presence of symptoms with the range and trajectory of opening, and the area included in what is described as a polygon of Posselt in the frontal and sagittal plane. No significant differences were found between the answers to each question between men and women. According to the responses and to Delcanho, 12 participants turned out to need a more exhaustive evaluation. In this group it was found that the area of the Posselt polygon in the frontal plane was significantly smaller than that of those participants who did not require a more extensive evaluation (p = 0.003). The values of the mandibular opening path vary depending on the symptom involved. The main symptoms that would affect the values of the bordering movements are the "difficulty to open the mouth" and "noise in the mandibular joints". With this study, we have shown that the limitation of mandibular movement as a sign of TMD should be assessed with caution, as, according to the presence of certain symptoms and other characteristics of subjects (such as sex), its value may vary.

Effects of speaking rate, loudness, and clarity modifications on kinematic endpoint variability.

It is virtually impossible for a speaker to produce identical articulatory movements across several repetitions of the same utterance. This study examined how kinematic endpoint variability, defined as the positional variability of an articulator at its positional extremum, changes in response to cued speech behavioral modifications. As a second step, this study examined the strength of association between articulator speed and kinematic endpoint variability. Seventeen speakers repeated the sentence "Buy Kaia a kite" 10 times under the following conditions: typical, loud, slow, and clear speech. Speech movements were recorded using 3D electromagnetic articulography. Endpoint variability was measured at the maximum jaw opening position during "buy" and at the maximum elevation of the tongue back during /k/ in "Kaia". Significant speech modification effects were found for the jaw but not for the tongue. Specifically, typical speech yielded significantly lower kinematic endpoint variability than slow and loud speech. Further, jaw peak speed was moderately correlated with kinematic endpoint variability (r = .43, p < .01). Findings for jaw movements suggest that speech modifications that elicit an increase in speed (i.e. loud speech) may negatively impact kinematic endpoint precision; however, other factors such as motor learning and lacking emphasis on spatial precision (i.e. slow speech) may also play a role.

A first investigation of tongue, lip, and jaw movements in persons with dysarthria due to multiple sclerosis.

BACKGROUND: Multiple sclerosis can affect the speech motor system and result in dysarthria. OBJECTIVES: This pilot study sought to identify tongue, lip, and jaw motor deficits in persons with dysarthria due to multiple sclerosis (PwDMS) to better understand the speech motor mechanisms that underlie their aberrant speech. METHODS: Tongue and jaw movements during "ai" and lower lip and jaw movements during "bob"were examined in eleven PwDMS and fourteen age- and sex-matched controls using three-dimensional electromagnetic articulography. Movement duration, maximum displacement, peak speed, stiffness (i.e., peak speed/displacement ratio), and jaw contribution to lower lip and tongue displacements were of particular interest. RESULTS: Whereas most kinematic measures yielded significant between-group differences for tongue and jaw motor performance during "ai", lower lip and jaw motor performance during "bob" were mostly comparable between groups. CONCLUSION: Findings suggest that speech movements of the tongue are differentially more impaired than those of the lower lip in PwDMS. Particularly the ability to move the tongue with adequate speed during speech was significantly impaired in PwDMS, which may explain, in part, their slowed speech rate. Aberrant jaw kinematics during "ai" may be a compensatory strategy to maximize speech clarity in the presence of the impaired tongue motor performance.

A Novel Three-Dimensional Analysis of Tongue Movement During Water and Saliva Deglutition: A Preliminary Study on Swallowing Patterns.

Deglutition is a complex oral function, and the study of the whole process requires a precise analysis of the elements involved, especially of the tongue biomechanics. We described a three-dimensional analysis of tongue movements during both saliva and water deglutition in participants with normal occlusion. Fourteen participants (25.36 ± 4.85 years) were evaluated, and the movements of anterior, middle, and posterior portions of the tongue were recorded using AG501 3D-electromagnetic articulograph. An average volume (AVS) for water deglutition was determined for each participant. Saliva deglutition was classified according to Bourdiol et al. 35.71% was type I, 14.29% type II, and 50% type III. The greatest displacement on the inferior-superior axis was in the posterior portion, followed by the middle and anterior portions. In the posterior-anterior axis, smallest movement was in the anterior portion. During water deglutition, on the inferior-superior axis, there were statistical differences for 1-AVS between the anterior/middle and anterior/posterior portions of the tongue. There were statistical differences for both ½-AVS and »-AVS between the anterior/posterior portions of the tongue. On the posterior-anterior axis, there were no statistical differences among any volume-portion relations. On the medial-lateral axis, there was statistical difference for the ½-AVS between middle and posterior portions. The movement of the tongue portions was influenced by the volume and the element to be swallowed. The amplitude of the movement was directly proportional to the volume of water swallowed.

Articulatory Kinematic Characteristics during Speech Production for Individuals with Dysarthria: A Study Based on Electromagnetic Articulography / 中国康复理论与实践

@#Objective:To explore the kinematics characteristics of articulators (including lips, tongue and jaw) during articulation in dysarthric individuals post brain injury by using electromagnetic articulography (electromagnetic articulography, EMA). Methods:From October, 2017 to October, 2018, six eligible individuals with dysarthria were recruited as dysarthria group, and ten age-gender matched healthy adults were recruited as healthy control group. Both groups received EMA assessment, and the dysarthria group was assessed with Chinese modified version of Frenchay Dysarthria Assessment before EMA assessment. To track and record kinematic parameters data (including duration, velocity, acceleration, distance) and displacement movement trajectories, a series of sensors were attached on the participant's lips, tongue (tip, blade and back of tongue) and jaw, the reference sensor was attached on the bridge of nose, all of the sensors were along midsagittal plane. During EMA assessment, each participant was received syllable repetition task, which containing consonants (/d/, /t/, /j/, /q/, /g/, /k/, /b/, /p/) at word initial position and vowels (/a/, /ia/, /iu/), to produce the single word with the Chinese linguistic meaning, every syllable produced was repeated three times. Then Praat software and Matlab software were used to process acoustic and kinematic data, so as to compare the differences of articulatory kinematic performance between two groups. Results:The outcome of the Frenchay Dysarthria Assessment indicated that the severity of dysarthria was from moderate to extreme severe. EMA assessment demonstrated that, compared with the healthy control group, the dysarthria group showed a reduction of velocity, acceleration and distance of tongue and lip movement (<italic>t</italic> > 2.422, <italic>P</italic> < 0.05), and longer duration of tongue tip, tongue back and jaw movement (<italic>t</italic> > 3.369, <italic>P</italic> < 0.05). There was no statistical difference in duration of tongue blade and lip movement (<italic>t</italic> < 2.146, <italic>P</italic> > 0.05), the same as the velocity, acceleration and distance of jaw movement between two groups (<italic>t</italic> < 1.016, <italic>P</italic> > 0.05). Image analysis of kinematics parameters and synchronous audio data showed that, compared with the healthy control group, the dysarthria group varied unstably in velocity and acceleration, and the audio data showed that, when repeated /da/ three times, the duration of each syllable was not equal. The coordination of articulation movement displacement in the anterior-posterior dimension and inferior-superior dimension was poor, there were significant differences in visual inspection of movement trajectories between two groups, and a smaller displacement was found in the anterior-posterior dimension in the dysarthric group. Conclusion:EMA assessment has significant advantages in evaluating kinematics parameters quantitatively, which could reveal the kinematics characteristics of articulators.

Lingual and Jaw Kinematic Abnormalities Precede Speech and Swallowing Impairments in ALS.

Early identification of bulbar involvement in persons with ALS is critical for improving diagnosis and prognosis; however, efficacious diagnostic markers have not yet been identified. The purpose of this study was to determine whether kinematic changes of the tongue and jaw during swallowing, measured using 3D electromagnetic articulography (EMA), predate clinically identifiable symptoms of speech and swallowing impairment in persons diagnosed with ALS. Data were collected from 16 adults diagnosed with ALS and 18 neurotypical controls. Groups were aged matched. Eligible participants with ALS were tolerating an unrestricted diet (FOIS = 7), produced intelligible speech (> 97%), and had a speaking rate greater than 150 words per minute. Participants completed a 3-mL water swallow task, during which EMA recorded kinematic measures of the anterior and posterior regions of tongue including lingual speed, range of motion, duration, coordination, and efficiency. Jaw speed and range of motion were also recorded. Persons diagnosed with ALS demonstrated reduced posterior lingual range of motion (11.40 mm ± 4.01 vs. 16.07 mm ± 5.27), slower posterior lingual speeds (83.67 mm/s ± 47.96 vs. 141.35 mm/s ± 66.54), increased lingual movement duration (13.46 s ± 6.75 vs. 9.21 s ± 3.28), and reduced lingual coordination (0.04 s ± 0.11 vs. 17 s ± 0.19) during the 3-oz water swallow task compared to controls. Persons diagnosed with ALS demonstrated increased range of motion (9.86 mm ± 5.38 vs. 6 mm ± 3.78) and increased jaw speed (68.62 mm/s ± 50.13 vs. 34.72 mm/s ± 17.75) during swallowing compared to controls. The current findings suggest that changes in lingual and jaw motor performance during a simple water swallow task are present in persons with ALS who are pre-symptomatic of clinically detectable bulbar impairment.

[An acoustic-articulatory study of the nasal finals in students with and without hearing loss].

The central aim of this experiment was to compare the articulatory and acoustic characteristics of students with normal hearing (NH) and school aged children with hearing loss (HL), and to explore the articulatory-acoustic relations during the nasal finals. Fourteen HL and 10 control group were enrolled in this study, and the data of 4 HL students were removed because of their high pronunciation error rate. Data were collected using an electromagnetic articulography. The acoustic data and kinematics data of nasal finals were extracted by the phonetics and data processing software, and all data were analyzed by t test and correlation analysis. The paper shows that, the difference was statistically significant ( P<0.05 or P<0.01) in different vowels under the first two formant frequencies (F1, F2), the tongue position and the articulatory-acoustic relations between HL and NH group. The HL group's vertical movement data-F1 relations in /en/ and /eng/ are same as NH group. The conclusion of this study about participants with HL can provide support for speech healing training at increasing pronunciation accuracy in HL participants.