Nerve entry points in the mimic musculature of the horse head.

Facial expressions are important in pain recognition in horses, but current observation-based pain scales remain subjective. A promising technique to quantitatively measure subtle changes in expression patterns, including changes invisible to the human eye, is surface electromyography (sEMG). To achieve high-quality and reliable sEMG signals, unilateral placement of bipolar electrodes is required in relation to the motor endplates (MEP). We aimed to localize the nerve entry points (NEPs; where the nerve branch first pierced the muscle belly) and the direction of the terminal nerve endings to estimate MEP locations of the innervating nerves in five equine facial muscles involved in pain expression. Three cadaveric Dutch Warmblood horse heads were dissected to identify the NEPs in the musculi caninus, levator anguli oculi medialis, nasolabialis, masseter and zygomaticus. These points were marked with pins and measured in relation to a reference line between two anatomical landmarks near the origin and insertion of the respective muscle. Relative distances were calculated from the most caudally situated landmark. NEPs were located at 33%-38% (caninus), 69%-86% (levator anguli oculi medialis) and 0%-18% (zygomaticus) from the caudal landmark. The nasolabialis showed two innervations zones. Its NEPs were located at 47%-72% (dorsal muscle branch) and 52%-91% (ventral branch). All terminal nerve endings were found to run in rostral direction. The masseter showed numerous NEPs diffusely spread within the muscle belly. Therefore, calculation of relative positions was not performed. These results could form the basis for feasibility studies and standardization of bipolar electrode positioning in vivo to measure facial muscle activity patterns in horses.

Sonoanatomy of injecting botulinum neurotoxin into the facial muscles.

INTRODUCTION: Ultrasonography (US) has become an essential tool for guiding botulinum neurotoxin (BoNT) injections in facial muscles, enhancing precision and safety. This narrative review explores the role of US in BoNT administration, particularly in complex anatomical regions, highlighting its impact on treatment customization, real-time visualization, and complication reduction. MATERIALS AND METHODS: A comprehensive literature search was conducted using PubMed, MEDLINE, Embase, and Cochrane Library for articles published from January 2018 to December 2023. Search terms included "Botulinum neurotoxin," "facial anatomy," "ultrasonography guided injection," and "facial muscle sonoanatomy." Studies focusing on US-guided BoNT injections in facial muscles were included. Data extraction and synthesis were performed independently by two reviewers, focusing on study design, ultrasonography techniques, outcomes, and conclusions. RESULTS: The review found that US guidance significantly enhances the precision of BoNT injections by providing real-time visualization of facial muscles and blood vessels, thereby reducing the risk of adverse events. US enables tailored injection strategies, ensuring symmetrical facial expressions and minimizing over-treatment. The technique also offers immediate feedback, allowing for on-the-spot adjustments to improve treatment efficacy and safety. However, the review identified limitations, including potential selection bias and variability in US techniques across different studies. CONCLUSION: US guidance for BoNT injections into facial muscles offers substantial benefits in terms of precision, safety, and treatment customization. Despite the identified limitations, the integration of US into clinical practice is poised to enhance patient outcomes in aesthetic and therapeutic procedures. Further research is needed to standardize US techniques and broaden the inclusivity of studies to validate these findings comprehensively.

The three layered structure of orbicularis oris and buccinator complex with partial connection at the modiolus and partial direct continuation.

PURPOSE: This study aimed to clarify the structural arrangement of the orbicularis oris (OOr), the buccinator, and the other perioral muscles around the modiolus. METHODS: The perioral muscles in seventeen cadavers fixed with formalin were dissected in situ and/or in isolated muscle specimens, and their layers were reconstructed schematically upon pantomographic view of the skeleton to evaluate their actions. RESULTS: The buccinator was composed of three parts including upper and lower oblique parts in its superficial layer and a middle transverse part in its deep layer. The superior and inferior OOr were composed of an inner marginal part (IM) and an outer labial part (OL) in each. The perioral muscles as a whole were arranged in three layers. The first layer consisted of the depressor anguli oris and the OL of superior OOr connected at the modiolus in a vertical direction. The second layer consisted of the upper and inner oblique part of buccinator and a part of the OL of inferior OOr connected at the modiolus in a horizontal direction. The third layer contained the middle transverse part of buccinator continuous with the IM of both OOr and a part of the OL of inferior OOr without connection to the modiolus. CONCLUSIONS: The different arrangement of the three layers of perioral muscles around the modiolus could serve as a good basis to predict the actions of the individual perioral muscles on the movement of lips in open/close of the oral fissure and widening/narrowing of the lip width.

New method for analysing spatial relationships of facial muscles on MRI: a pilot study.

Dysfunction of the facial musculature can have significant physical, social, and psychological consequences. In surgeries such as cleft surgery or craniofacial bimaxillary osteotomies, the perioral facial muscles may be detached or severed, potentially altering their functional vectors and mimicry capabilities. Ensuring correct reconstruction and maintenance of anatomical sites and muscle vectors is crucial in these procedures. However, a standardized method for perioperative assessment of the facial musculature and function is currently lacking. The aim of this study was to develop a workflow to analyse the three-dimensional vectors of the facial musculature using magnetic resonance imaging (MRI) scans. A protocol for localizing the origins and insertions of these muscles was established. The protocol was implemented using the 3DMedX computer program and tested on 7 Tesla MRI scans obtained from 10 healthy volunteers. Inter- and intra-observer variability were assessed to validate the protocol. The absolute intra-observer variability was 2.6 mm (standard deviation 2.0 mm), and absolute inter-observer variability was 2.6 mm (standard deviation 1.5 mm). This study presents a reliable and reproducible method for analysing the spatial relationships and functional significance of the facial muscles. The workflow developed facilitates perioperative assessment of the facial musculature, potentially aiding clinicians in surgical planning and potentially enhancing the outcomes of midface surgery.

Increasing Precision When Targeting the Depressor Anguli Oris Muscle With Neuromodulators: An Ultrasound-Based Investigation.

BACKGROUND: Neuromodulator treatments of the perioral region are increasingly popular and aim to modulate the position of the modiolus. The predominantly targeted muscle is the depressor anguli oris (DAO) which allows for the modiolus to reposition cranially once temporarily relaxed. OBJECTIVES: The aim of this study was to identify the precise anatomic position of the DAO in relation to the marionette line, thereby increasing precision and reducing adverse events during neuromodulator treatments. METHODS: A total of n = 80 DAO muscles were investigated in n = 40 healthy, toxin-naïve volunteers (11 males, 29 females) with a mean [standard deviation] age of 48.15 [15] years and a mean BMI of 24.07 [3.7] kg/m2. The location of the DAO in relation to the labiomandibular sulcus, and its depth, extent, and thickness were investigated with high-frequency ultrasound imaging. RESULTS: The skin surface projection of the labiomandibular sulcus separates the DAO into medial and lateral portions. The distance between skin surface and muscle surface was on average 4.4 mm, with males having a greater distance (P < .001) and higher BMI being an important influencing factor for a greater distance (P < .001). The thickness of the DAO was on average 3.5 mm, with a range of 2.8 to 4.8 mm and with females having thinner muscles compared with males (P < .001). The most favorable injection depth was calculated to be 6.1 mm for intramuscular product placement. CONCLUSIONS: Understanding the perioral anatomy and the influence of age, sex, and BMI will potentially allow injectors to increase the efficacy and duration of neuromodulator treatments while expertly managing adverse events.

Investigating the Contraction Pattern of the Zygomaticus Major Muscle and its Clinical Relevance: A Functional MRI Study.

BACKGROUND: Our understanding of facial anatomy has significantly evolved, yet the detailed contraction patterns of facial muscles and their presentation during clinical imaging remain largely unexplored. Understanding the contraction patterns and visual presentation of these muscles, particularly the zygomaticus major could enhance pre-surgical facial assessments and the development of new treatment strategies. METHODS: A total of 34 healthy young individuals (17 female, 17 male) with a mean age of 23.6 (2.4) years [range: 20-30] were investigated regarding the length, thickness, width, and angle of the zygomaticus major muscle in five different facial expressions (i.e., repose, anger, joy, surprise, and sadness) utilizing MR imaging. RESULTS: Joyful expressions caused a reduction in muscle length to 85.6% of its original length and an increase in width (103.4%), thickness (108.4%), and facial angle (2.72°) when compared to that in repose, suggesting isotonic contraction. Conversely, expressions of anger, surprise, and sadness generally led to muscle stretching, seen through changes in length (98.9%, 104.3%, and 102.7%, respectively), width (98.8%, 96.5%, and 99.4%, respectively), and thickness (91.2%, 91.0%, and 102.7%, respectively), with variable alterations in facial angle (0.55°, 1.85°, and 1.00°, respectively) depending on the specific expression. CONCLUSION: This MRI-based study indicates that the zygomaticus major muscle experiences isotonic contraction, characterized by decreased length and increased width and thickness. The findings underline the importance of muscle thickness as a reliable parameter in assessing facial muscle function and offer valuable guidance for practitioners in accurately evaluating muscle performance during different facial expressions. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Deciphering Depressor Anguli Oris for Lower Face Rejuvenation: A Prospective Ultrasound-based Investigation.

BACKGROUND: The depressor anguli oris muscle (DAO) is a pivotal treatment target when creating a harmonic jawline. However, evidence of its live morphology remains scarce. OBJECTIVES: In this study we aimed to reevaluate the DAO with a facile ultrasound analysis and thereby guide safer and more effective botulinum toxin type A (BTX-A) injection. METHODS: A prospective ultrasound assessment was conducted in 41 patients. Morphology of the DAO and its relative position to neighboring structures were appraised at the ubiquitous facial landmark, the labiomandibular fold (LMF). Three-dimensional images were captured before and after the patient received the BTX-A injection based on sonographic evidence. RESULTS: The skin-to-muscle depths of the DAO on average (measured from the medial to lateral border) were 5.26, 5.61, and 8.42 mm. The DAO becomes thinner and wider from zone 1 to zone 3 (P < .001). Overlapping lengths of the DAO and the depressor labii inferioris increased from zone 1 to zone 3: 4.74, 9.68, 14.54 mm (P < .001). The medial border of the DAO was located at 4.33, 6.12, 8.90 mm medial to the LMF (zone 1-3), and no muscle fibers of the DAO were observed in zone 1 or zone 2 in nearly one-third of patients. Improvement of the mouth corner downturn angle upon receiving BTX-A injection at zones 2 and 3 were 88.3%, 32.3%, and 14.7% for the neutral, maximum smile, and down-turning mouth corner expressions. CONCLUSIONS: This work established an informative ultrasound portrait of the DAO and structures in the perioral region, which suggested the LMF as a convenient landmark for locating the DAO. Injection at the middle and lower thirds of the LMF at a 4- to 5-mm depth is recommended.

Anatomical and Ultrasonographic Analyses of the Levator Labii Superioris Alaeque Nasi Muscle at the Level of the Nasal Ala / Análisis Anatómico y Ecográfico del Músculo Elevador Nasolabial a Nivel del Ala Nasal

SUMMARY: We aimed to determine the width of the levator labii superioris alaeque nasi muscle (LLSAN) at the level of the nasal ala through cadaveric dissections and ultrasonography (US), to provide essential anatomical information for use during both invasive and noninvasive procedures in the nasal ala region. The LLSAN was investigated in the 40 hemifaces of 20 Korean cadavers, comprising 10 males and 10 females with a mean age of 73.6 years. The LLSAN width of the 40 specimens at the level of the midpoint of the nasal ala was 5.02±2.35 mm (mean±standard deviation), and ranged from 1.45 mm to 10.11 mm. The LLSAN widths were 5.96±2.36 mm and 3.93±1.89 mm in males and females, respectively, with ranges of 2.40-10.11 mm and 1.45-6.96 mm, respectively. The LLSAN widths on the left and right sides were 4.77±2.72 mm and 5.26±1.99 mm, respectively. The proportions of the LLSAN fibers inserting into the nasal ala and upper lip were similar in 13 specimens (32.5 %), while more fibers inserted into the nasal ala in 11 specimens (27.5 %) and more fibers inserted fibers of the LLSAN into the upper lip in 16 specimens (40 %). When clinicians need to target or avoid the LLSAN, the present width and range data can be helpful for ensuring the efficacy and safely of both invasive and noninvasive procedures. In addition, the possibility of asymmetry in the width of the LLSAN in the nasal ala region should be confirmed by US before performing such procedures.

Nuestro objetivo fue determinar el ancho del músculo elevador nasolabial (MENL) a nivel del ala nasal mediante disecciones cadavéricas y ecografía, para proporcionar información anatómica esencial, para su uso durante procedimientos invasivos y no invasivos, en la región del ala nasal. El MENL se estudió en 40 hemicaras de 20 cadáveres coreanos (10 hombres y 10 mujeres) con una edad media de 73,6 años. El ancho de MENL de las 40 muestras a nivel del punto medio del ala nasal fue de 5,02 ± 2,35 mm (media ± desviación estándar) y osciló entre 1,45 mm y 10,11 mm. Los anchos de MENL fueron 5,96 ± 2,36 mm y 3,93 ± 1,89 mm en hombres y mujeres, respectivamente, con rangos de 2,40 a 10,11 mm y 1,45 a 6,96 mm, respec- tivamente. Los anchos de MENL en los lados izquierdo y derecho fueron 4,77 ± 2,72 mm y 5,26 ± 1,99 mm, respectivamente. Las proporciones de fibras de MENL que se insertaban en el ala nasal y en el labio superior fueron similares en 13 muestras (32,5 %), mientras que se insertaron más fibras en el ala nasal en 11 muestras (27,5 %) y además, se insertaron fibras de MENL en el labio superior en 16 ejemplares (40 %). Cuando los médicos necesitan apuntar o evitar el MENL, los datos actuales de ancho y rango pueden ser útiles para garantizar la eficacia y seguridad de los procedimientos, tanto invasivos como no invasivos. Además, la ecografía puede ser utilizada para confirmar una posible asimetría en el ancho del MENL en la región del ala nasal antes de realizar los procedimientos.

Correlation of 3D Morphometric Changes, Kinematics, and Muscle Activity During Smile.

OBJECTIVE: Knowing the morphological, kinematic, and electrophysiological parameters of the smile in healthy individuals may contribute to evaluating, planning, and monitoring the smile reanimation. This study aimed to determine the correlation between 3D morphometric changes, movement kinematics, and muscle activity in the facial soft tissue of healthy individuals. METHOD: In this cohort study, 20 volunteers were selected from healthy individuals with no facial disorders. During smiling, three-dimensional face scanning, facial motion capture, and surface electromyography (sEMG) were performed. The average displacement, velocity, and acceleration during facial movements were measured. The mean change in 3D surface morphometry and activation of the zygomaticus major were determined. RESULTS: The volunteers, comprising 10 males and 10 females, had a mean age of 24 ± 10 years; for female, mean age was 23 ± 5 years and for men 26 ± 13 years. Significant correlations were found between kinematic and morphometric data (r = 0.51, p < 0.001), sEMG and morphometric (r = 0.50, p < 0.001) data, and sEMG and kinematic data (r = 0.49, p < 0.002). The maximum acceleration occurred during approximately 65% of the muscle activation time and 64% of the peak muscle activation value. Additionally, the maximum velocity was reached at around 73% of the muscle activation time and 67% of the peak muscle activation value. Furthermore, the maximum displacement values were observed at approximately 88% of the muscle activation time and 76% of the peak muscle activation value. CONCLUSION: The findings may provide insights into the smile's functional parameters, contribute to understanding facial muscle-related disorders, and aid in improving the diagnosis and treatment of the smile. LEVEL OF EVIDENCE: NA Laryngoscope, 134:3112-3119, 2024.

Anatomical connections between the inferior fibers of the musculus orbicularis oculi and musculus levator labii superioris alaeque nasi / Conexiones anatómicas entre las fibras inferiores del músculo orbicular del ojo y levantador nasolabial

SUMMARY: This study aimed to determine the anatomical connections between the inferior fibers of M. orbicularis oculi (OOc inf.) and the M. levator labii superioris alaeque nasi (LLSAN), providing anatomical variations of the connecting fibers. This study examined the OOc and LLSAN of 44 specimens from 22 embalmed adult Korean cadavers. Connecting fibers between the OOc inf. and LLSAN were observed in 29.5 % of the specimens. Connecting patterns of the OOc inf. to the LLSAN were classified into three categories according to the directions of the connecting fibers; Type I (13.6 %), in which some of the OOc inf. coursed medially to blend with the lateral originating fibers of the LLSAN. Type II (11.4 %), in which some of the OOc inf. descended vertically to blend with the LLSAN. Type III (4.5 %), in which both types I and II were found simultaneously. Some of the OOc inf. coursed medially to blend with the lateral originating fibers of the LLSAN, and some of the OOc inf. descended vertically to blend with the LLSAN. These findings provide greater knowledge of the connecting fibers between the OOc inf. and LLSAN, thereby helping us understand complicated expressions, inject BoNT-A into related wrinkles, and analyze EMG activities.

RESUMEN: Este estudio tuvo como objetivo determinar las conexiones anatómicas entre las fibras inferiores del músculo orbicular del ojo (MOO inf.) y el levantador nasolabial (Musculus levator nasiolabialis; M. levator labii superioris alaeque nasi) (LNL), proporcionando variaciones anatómicas de las fibras conectoras. Se examinó el orbicularis oculi (MOO) y LNL de 44 especímenes de 22 cadáveres coreanos adultos embalsamados. Se observaron fibras conectoras entre los MOO inf. y LNL en el 29,5 % de los especímenes. Patrones de conexión del OOc inf. a LNL se clasificaron en tres categorías según las direcciones de las fibras conectoras; Tipo I (13,6 %), en el que algunos de los MOO inf. cursaban medialmente para mezclarse con las fibras de origen lateral del LNL. Tipo II (11,4 %), en el que algunos de los MOO inf. descendían verticalmente para mezclarse con el LNL. Tipo III (4,5 %), en el que se encontraron simultáneamente los tipos I y II. Algunos de los MOO inf. cursaron medialmente para mezclarse con las fibras de origen lateral de la LNL y algunas de las MOO inf. descendían verticalmente para mezclarse con el LNL. Estos hallazgos aportan un mayor conocimiento de las fibras conectoras entre los MOO inf. y LNL, lo que nos ayuda a comprender expresiones complicadas, inyectar BoNT-A en las arrugas relacionadas y analizar las actividades de EMG.

Comunicación preliminar acerca de la disposición morfológica, la funcionalidad y las implicancias clínicas del modiolo del ángulo oral (Modiolus anguli oris) / Preliminary communication about the morphological arrangement, functionality and clinical implications of modiolus of angulus oris (Modiolus anguli oris)

RESUMEN: La disposición anatómica de los músculos faciales es de una notable complejidad y requiere de un estudio pormenorizado para lograr su reconomiento preciso. La comprensión de la disposición morfológica y la funcionalidad del modiolo del ángulo oral (Modiolus angulis oris) es de gran relevancia al momento de analizar la constitución muscular de la comisura labial, y para comprender clínicamente las lesiones del ángulo de la cavidad oral, lo que permitirá un abordaje terapéutico adecuado, crucial para la preservación y reconstitución de la armonía facial.

SUMMARY: The anatomical arrangement of the facial muscles is of considerable complexity and requires a detailed study to achieve its precise recognition. The understanding of the morphological disposition and the functionality of the angle of the mouth (Modiolus angulis oris) is of great relevance when analyzing the muscular constitution of the labial commissure, and to understand clinically the injuries of the angulus oris, what that will allow an adequate therapeutic approach, crucial for the preservation and reconstitution of facial harmony.

Transversus nuchae muscle fused with risorius muscle: a case report / Músculo transverso de la nuca fusionado con músculo risorius: informe de un caso

SUMMARY: Facial muscles are known to have a variable anatomy. Such anatomical variations can affect facial expressions. A natural smile is produced by contracting several muscles of facial expression, including the muscles invested in the superficial musculoaponeurotic system. Change in the width of the mouth on smiling is a known iatrogenic complication affecting the risorius muscle when using Botulinum Neurotoxin as a non-invasive treatment for masseteric hypertrophy. Also damage to the risorius muscle, with consequent clinical deficits, is a common surgical complication in facial aesthetic, oncologic and other head and neck procedures such as parotidectomy and rhytidectomy. Hence, a thorough knowledge of muscle anatomy, particularly its potential variations, is critical in reducing the associated operative morbidity. Accordingly, we report an unusual variation of the transversus nuchal muscle fused with the risorius muscle noted in an 83-year-old female body cadaver.

RESUMEN: Los músculos faciales tienen una anatomía variable. Tales variaciones anatómicas pueden afectar las expresiones faciales. Una sonrisa natural se produce al contraer varios músculos de la expresión facial, incluidos los músculos invertidos en el sistema musculoaponeurótico superficial. El cambio en el ancho de la boca al sonreír es una complicación iatrogénica conocida, que afecta el músculo risorio cuando se usa la neurotoxina botulínica como un tratamiento no invasivo para la hipertrofia masterérica. Además, el daño al músculo risorio, con los consecuentes déficits clínicos, es una complicación quirúrgica común en la estética facial, oncológica y otros procedimientos de cabeza y cuello, como la parotidectomía y la ritidectomía. Por lo tanto, un conocimiento profundo de la anatomía muscular, particularmente sus posibles variaciones, es crítico para reducir la morbilidad operativa asociada. En consecuencia, informamos una variación inusual del músculo transverso de la nuca fusionado con el músculo risorio, observado en un cadáver de cuerpo femenino de 83 años.

Efeitos do uso de diferentes tecnologias educacionais na aprendizagem conceitual sobre o sistema miofuncional orofacial / Effects of the use of different educational technologies in conceptual learning of the orofacial myofunctional system

RESUMO Objetivo Comparar três métodos de aprendizagem sobre anatomia e fisiologia do sistema miofuncional orofacial, sendo dois interativos (uso de softwares educacionais) e um tradicional, quanto à aprendizagem conceitual de estudantes de graduação em Fonoaudiologia. Métodos Participaram 36 estudantes do segundo ano, alocados randomicamente em grupos: Grupo 1 (G1) - método interativo com jogo computacional 2D (n=12); Grupo 2 (G2) - método interativo com modelo computacional 3D (n=12); Grupo 3 (G3) - método tradicional (textos e figuras 2D) (n=12). Os métodos de aprendizagem foram aplicados durante estudo complementar, por sete semanas, após aula expositiva. Foi realizada uma avaliação de conhecimento antes da aplicação dos métodos de aprendizagem, imediatamente após e seis meses depois da conclusão, e o desempenho dos grupos, nos três momentos, foi comparado. Os dados foram analisados no software SPSS, versão 21 (nível de significância de 5%). Resultados Predominaram sujeitos do gênero feminino, com média de idade de 22,0 (±4,7) anos (F2,33=60,72, p=0,260). Os resultados indicaram que, no G1, apenas o pré-teste diferiu do pós-teste, enquanto no G2 e no G3 o pré-teste diferiu do pós-teste e do pós-teste tardio. Ao verificar a interação entre o desempenho dos grupos e os momentos de avaliação, observou-se que os resultados do GI foram inferiores aos dos demais grupos (F2,22=722,30 p<0,001). Conclusão O uso de modelo computacional 3D foi comparável ao do método tradicional para a aprendizagem conceitual e retenção de conhecimento, em curto e longo prazo, sendo ambos mais eficazes do que o uso de jogo computacional 2D.

ABSTRACT Purpose Compare three learning methods on Anatomy and Physiology of the Orofacial Myofunctional System (OMS): two interactive methods with educational software and one traditional method, regarding the conceptual learning of Speech-Language and Hearing Sciences (SLHS) undergraduate students. Methods Thirty-six students were randomly divided into three groups: Group 1 (G1) - 2D computer game-based method (n=12); Group 2 (G2) - 3D computational model method (n=12); Group 3 (G3) - traditional method (texts and 2D images) (n=12). The learning methods were applied during a complementary study schedule, for seven weeks, after a lecture. Knowledge assessments were conducted prior to the application of the learning methods, immediately after, and six months after completion; the performance of the groups at the three moments was compared. Data were analyzed in SPSS 21 software (p≤0.005). Results Female individuals were predominant, with mean age of 22.0 (±4.7) years (F2.33=60.72; p=0.260). The results show that only the pre-test differed from the short-term test in the G1, whereas the pre-test differed from the short- and the long-term tests in the G2 and G3. Regarding correlation between the performance of the groups and the moments of evaluation, it was observed that the results for the G1 were inferior (F2.22=722.30; p<0.001). Conclusion The 3D computational model was comparable to the traditional method for short- and long-term conceptual learning and knowledge retention, and both were more effective than the 2D computer game.

Histological aspects of the mucosa of the spermaceti chamber of a dwarf sperm whale / Aspectos histológicos da mucosa da câmera do espermacete de cachalote-anão

The sound producing apparatus of the dwarf sperm whale (Kogia sima) presents a complex anatomic structure composed of melon, spermaceti, phonic lips, vocal cap, case, papillae, spermaceti chamber and other airspaces, as well as facial muscles involved in sound production. The spermaceti chamber rests on the caudal portion of the premaxilla, with part of its mucosa covered with spherical/oval-shaped structures (approximately 1 to 2 mm in diameter), compatible with vesicles (previously referred to as "papillae"). Macroscopical examination revealed whitish, firm, widely and irregularly distributed vesicular mucosa on the premaxillary portion of the spermaceti chamber of a K. sima specimen stranded on the coast of Santos (southeastern Brazilian coast). Upon microscopic examination, walls of connective tissue with abundant type I collagen forming vesicles with an internal space or cavity filled with a small amount of eosinophilic substance compatible with mucoproteic fluid were observed. The base of such vesicles presented glands within the connective tissue, probably responsible for fluid production. This study describes the histology of the mucosa of the spermaceti chamber of a K. sima specimen and characterizes the glands associated with fluid production.(AU)

O sistema de produção sonora do cachalote-anão (Kogia sima) apresenta uma complexa estrutura anatômica composta por melão, espermacete, lábios fônicos, "vocal cap", "case", papilas, câmara do espermacete e outros espaços aéreos, além de músculos faciais envolvidos na produção sonora. A câmara do espermacete localiza-se na porção caudal da pré-maxila, apresentando parte de sua mucosa recoberta por estruturas esférico-ovaladas de aproximadamente 1 a 2 mm de diâmetro, compatíveis com vesículas (previamente denominadas "papilas"). Ao exame macroscópico de um espécime de K. sima encalhado no litoral de Santos (sudeste da costa brasileira), foi identificada mucosa esbranquiçada e firme ao corte, ampla e irregularmente distribuída na porção pré-maxilar da câmara do espermacete. Ao exame microscópico foram observadas vesículas compostas por abundante tecido conectivo de colágeno tipo I, dando origem a um espaço interno ou cavidade, contendo pequena quantidade de substância eosinófila, compatível com fluido mucoprotêico. Estruturas glandulares foram observadas em tecido conjuntivo na base das vesículas, provavelmente responsáveis pela produção do fluido observado no interior das mesmas. Esse estudo caracteriza histologicamente a mucosa da câmara do espermacete de um espécime de K. sima e as glândulas relacionadas a sua produção secretória.(AU)

The peculiarities of the masticator muscles in rodents / Particularidades da masculatura mastigatória dos roedores

Comparative research concerning masticatory musculature in squirrel, muskrat and rabbit, take into account the emphasizing and morphofunctional interpretation of the osteomuscular particularities involved in the prehension and mastication processes. The development of the coronoid process on the muskrat and squirrel demonstrates the growing of the force when raising the mandible by increasing the action force attached to the temporal muscle, with insertion on the coronoid process. In comparison with that, in the case of rabbits, both the coronoid process and the temporal muscle are reduced. From a philogenetic point of view, it has been found that the species that have the articular condyle lowered at or under the level of the dental tables (carnivores) present a greater pressure force between the dental tables. Analyzing this aspect of the rodents taken into discussion, we noticed the lowering of the articular condyle up to the inferior molars' plane, in the case of squirrels and muskrats, but through obliquity, namely through cranial caudal and dorsoventral movement. This peculiarity is emphasized through the analysis of the angle formed by the axis of the mandible recurved branch (passing through the mandibular condyle) with the axis of the horizontal branch of the mandible, where it was noticed that along with the increase in the angle formed by the two axes, which becomes an obtuse 160 degree angle on the squirrel and 130 degrees on the muskrat, there is also a lowering of the articular condyle up to the molar level, while in the case of carnivores, the lowering of the condyle is done without the modification of the angle between the two axes, which measures approximately 90 degrees.

Investigações comparativas com respeito à musculatura mastigatória do esquilo, do rato-almiscarado e do coelho buscam o realçamento e a interpretação morfo-funcional das particularidades do sistema dos músculos esqueléticos envolvido no processo de agarramento e mastigação. O desenvolvimento do processo coronoide no rato-almiscarado e no esquilo demonstra o aumento da força no levantamento da mandíbula por meio do aumento do braço da força de ação do músculo temporal com inserção sobre o processo coronoide, em comparação com os leporídeos, que têm tanto o processo coronoide como o músculo temporal mais reduzidos. Do ponto de vista filogenético, observa-se que as espécies que apresentam o côndilo articular baixado igual ou inferior ao nível das placas dentárias (carnívoros) apresentam uma força de pressão maior entre as placas dentárias. Em relação aos roedores estudados, nota-se a descida do côndilo articular perto do plano dos molares inferiores no esquilo e no rato-almiscarado, mas por meio da obliquidade, isto é, por meio do movimento do côndilo articular da borda craniana e dorsoventral. Esta particularidade evidencia-se em virtude do ângulo formado pelo eixo do ramo dobrado da mandíbula (que atravessa o côndilo mandibular) junto ao eixo do ramo horizontal da mandíbula, resultando no aumento do valor do ângulo formado pelos dois eixos, que se tornam obtusos a 160º no esquilo e a 130º no rato-almiscarado, em função da descida do côndilo articular quase ao nível do plano dos molares, em comparação com os carnívoros, nos quais a descida do côndilo realiza-se sem a modificação do ângulo formado pelos dois eixos de, aproximadamente, 90 graus.

Anatomia e avaliação funcional do músculo frontal: estudos dos padrões de contração / Anatomy and functional evaluation of the frontalis muscle: study on contraction's patterns

Introdução: na face estão inseridos numerosos músculos, artérias, glândulas, veias e nervos. O arranjo anatômico do músculo frontal permite uma grande mobilidade à região frontal, sendo, pois considerado o músculo mimético do couro cabeludo. A interpretação de cada uma das emoções apresenta diferenças substanciais: o temor, conforme esperado, é detectado quase que exclusivamente na parte superior do rosto. Objetivo: classificar os padrões de contração do músculo frontal de estudantes do curso de fisioterapia de uma Universidade da cidade de Bauru, estado de São Paulo. Material e Método: Trata-se de uma análise retrospectiva de fotografias de 105 sujeitos. Resultados: obteve-se uma imagem da face do sujeito com o músculo frontal em repouso e a segunda durante a contração máxima do músculo frontal. Quatro padrões foram identificados por quatro examinadores em: total, medial, lateral, hipocinesia. O padrão total foi observado em 32,4 por cento examinador A, 36,1 por cento examinadores B e C, 30,4 por cento examinador D. O padrão medial foi de 25,7 por cento examinador A, 23,8 por cento examinador B, 27,6 por cento examinador C, 29,5 por cento examinador D. O padrão lateral foi de 11,4 por cento examinadores A e D, 16,1 por cento examinador B e 14,2 por cento examinador C. O padrão hipocinesia foi de 30,5 por cento examinador A, 23,8 por cento examinador B, 21,9 por cento examinador C e 28,5 por cento examinador D. Conclusão: conclui-se que o conhecimento dos vários padrões de contração do músculo frontal, permite um planejamento e intervenção fisioterapêutica mais eficiente e preciso.

Introduction: numerous muscles, arteries, small glands, blood vessels and nerves are inserted in the face. The anatomical arrangement of the frontalis muscle allows vast mobility to the frontal region, and is therefore considered the mimetic muscle of the scalp. The interpretation of each of the emotions shows essential differences: the fear, as expected, is detected almost exclusively in the upper face. Objective: classify the patterns of frontalis muscle contractions in students of physiotherapy in a University, located in Bauru, state of São Paulo, Brazil. Material and Method: this is a retrospective analysis of pictures taken from 105 subjects. Results: The first picture of the subject's face was taken with the frontalis muscle at rest and the second one, in maximal contraction of the frontalis muscle. Four patterns were identified by four examinators: total, medial, lateral, hypokinesia. The total pattern was observed in 32.4 per cent, examinator A; 36.1 per cent by examinators B and C; and 30.4 per cent, examinator D. The medial pattern was observed in 25.7 per cent, examinator A; 23.8 per cent examinator B; 27.6 per cent , examinator C and 29.5 per cent, examinator D. The lateral pattern was observed in 11,4 per cent, examinators A and D; 16,1 per cent, examinator B; and 14,2 per cent examinator C. The hypokinesia pattern was observed in 30,5 per cent, examinator A; 23,8 per cent, examinator B; 21,9 per cent examinator C; and 28,5 per cent, examinator D. Conclusion: we conclude that the knowledge of the several patterns of frontalis muscle contractions, allows a more efficient and accurate planning and interventions in physioytherapy.

Reconstrução facial: mensuração da espessura dos tecidos moles que recobrem a face / Facial reconstruction: measurement of the soft tissue´s thickness that covers the face

Reconstrução facial forense é uma técnica utilizada com a finalidade de reconhecimento e posterior identificação, nas situações em que inexiste uma identidade atribuível ao esqueleto submetido à perícia médico-legal. Objetivou-se neste estudo mensurar as espessuras de tecidos moles que recobrem a face em cadáveres que deram entrada no Instituto Médico Legal (IML) de Guarulhos no período de setembro de 2010 a setembro de 2011. Foram efetuadas mensurações de 49 pontos anatômicos da face em cadáveres com menos de 24 horas do óbito; tais mensurações foram analisadas por meio do teste t com p bicaudal. O projeto foi aprovado pelo Comitê de Ética em Pesquisa da FOUSP (protocolo 144/2010). Um total de 100 cadáveres foi estudado, sendo 64 do sexo masculino e 26 do sexo feminino. Eles pertenciam majoritariamente à faixa etária de 41 a 60 anos. Optou-se por utilizar nomenclatura em língua inglesa com a finalidade de facilitar comparações com trabalhos internacionais

Dos 49 marcos mensurados, apenas cinco apresentaram um p menor que 0,05, ou seja, para os seguintes pontos as medidas entre homens e mulheres não são as mesmas quando comparadas em relação ao sexo: upper lip margin (p=0,006), superior labius sulcus (p=0,006), stomion (p=o,001), lateral orbits direito (p=0,008) e chelion esquerdo (p=0,009). Os pontos anatômicos analisados permitiram estabelecer parâmetros mais precisos de espessuras faciais aplicáveis na reconstrução facial de cadáveres da população brasileira. Além disso, os marcos anatômicos analisados permitiram a construção de uma tabela com finalidade de reconstrução facial forense.

Forensic facial reconstruction is a technique that has the aim of recognition and identification, in situations in which a known identity of the sketelon submetted to medico-legal procedures is not available. The objective of the study was to study the soft tissue thicknesses that cover the face of autopsied corpses that were sent to Guarulho´s Medical-Legal Institute from September 2010 to September 2011. Measurements of 49 anatomic references were performed in the face of corpses with less than 24 hours of death; data were analysed using t test with bicaudal p. The project was approved by the University of São Paulo´s School of Dentistry Ethics Committee (protocol number 144/2010). One hundred corpses were studied, being 64 male and 26 female. They were mainly 41 to 60 years old. Among all the 49 studied anatomic references, just five presented a p value lower than 0.05, that is, these references showed differences between sex: upper lip margin (p=0.006), superior labius sulcus (p=0.006), stomion (p=0,001), right lateral orbits (p=0.008) and left chelion (p=0.009). The studied anatomic references allowed to establish more precise parameters of the faces thicknesses that can be applied in corpses facial reconstructions in the Brazilian population, and some anatomic references presented a higher discriminant Power with regard to sex. Furthermore, the anatomic landmarks offered information to a reference table with the objective of forensic facial reconstruction.

Morfologia e variações anatômicas dos ventres frontaisdo músculo occipitofrontal: estudo anatômico eclassificação / Morphology and anatomical variations of the frontal bundles from the

Introdução: Com o desenvolvimento dos retalhos musculares, miocutâneos, osteomiocutâneos,microcirúrgicos e os novos procedimentos estéticos sobre o músculo occipitofrontal,tornou-se essencial o conhecimento anatômico desta região. Estudamos neste trabalho amorfologia detalhada dos ventres frontais e suas variações anatômicas, para que possamservir como pontos de referência úteis em cirurgias reparadoras e estéticas. Método: Foramestudados 56 cadáveres não fixados, 35 homens e 21 mulheres, 37 de raça branca e 19 nãobranca,com idade variando de 19 a 85 anos. Neste material foram dissecados 112 ventresmusculares. Resultados: Os dados obtidos foram colocados em tabelas, seguindo-se osparâmetros de sexo, idade, raça, distâncias interventrais, larguras, alturas e espessuras dosventres frontais bilateralmente. As larguras, espessuras e distâncias interventrais forammedidas a 1,5, 3,0 e 4,5 cm da glabela, em ambos os ventres. Os ventres frontais apresentaram-se de maneiras diferentes, principalmente quanto à disposição das fibras mediais,sendo agrupados em 4 tipos. Conclusões: O amplo conhecimento anatômico nos permiteum planejamento pré-operatório mais seguro.

Introduction: The development of muscles, myocutaneous, osteomiocutaneous, and thevariety of microsurgical flaps, added to the new aesthetic procedures on frontal bellies,became essential the well knowledge of this region. The studied in this paper covered thedetailed morphology of the frontal and their anatomical variations, that can serve as usefulreference points in reparative and cosmetic surgery. Methods: We studied 56 non-fixedcadavers, 35 men and 21 women, 37 white and 19 non-white, with age ranging from 19 to85 years old. In this material, 112 muscles were dissected. Results: Data were availablein tables followed by the parameters of sex, age, race, interventricular distances, heightsand widths of the frontal bilaterally. The widths, thickness and interventricular distanceswere measured at 1.5, 3.0 and 4.5 cm from the glabella in both wombs. The frontal werepresented in different ways, especially regarding the disposition of the medial and weregrouped into four types. Conclusion: The extensive anatomical knowledge allows us to apreoperative planning safer

Muscle fibre types and connective tissue morphometry in frontal muscle of Norfolk rabbits (Oryctolagus cuniculus) / Morfometría de los tipos de fibra muscular y del tejido conectivo en músculo frontal de conejos Norfolk (Oryctolagus cuniculus)

The frontal muscle is formed by a complex of contractile elements which compose the set of facial muscles responsible for the expression of emotions. In view of its functional characteristics the frontal muscle consists of a mixture of high (type I) and low oxidative (type II) muscle fibres. The objective of the present study was to determine the area, diameter, and relative volume occupied by each fibre type in frontal muscles of Norfolk rabbits using nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) histochemistry combined with morphometry. In addition, the connective tissue area (endomysium) and the number of blood vessels per fibre were evaluated. Female rabbits ranging in age from 6 to 8 months and weighing 2.8 to 3.1 kg were used. Four quadrants of samples from 12 animals were analysed. Type IIB fibres occupied the largest area compared to the other fibre types. The fibre diameter and relative volume were similar among the different fibre types identified by NADH-TR staining. No significant difference in the number of vessels per fibre was observed between the different fibre types. The endomysial area occupied the smallest area among the parameters analyzed. These findings demonstrated the intense activity of this muscle in the facial architecture of the animal. However, the low oxidative type II fibres predomination indicates more prone to muscle fatigue. The present findings may contribute to the study of myopathies involving this muscle.

El músculo frontal está formado por un complejo de elementos contráctiles que componen el conjunto de músculos faciales responsables de la expresión de emociones. A la vista de las características funcionales, el músculo frontal está constituido de una mezcla de fibras musculares de alto (tipo I) y bajo nivel de oxidación (tipo II). El objetivo del presente estudio fue determinar área, diámetro y volumen relativo ocupado por cada tipo de fibra en los músculos frontales de conejos Norfolk utilizando histoquímica para nicotinamide adenina dinucleotide tetrazolium reductasa (NADH-TR), combinado con su morfología. Además, fueron evaluados la zona de tejido conectivo (endomisio) y el número de vasos sanguíneos por fibras. Fueron utilizados conejos hembras, de edades comprendidas entre los 6 a 8 meses y con un peso de 2,8 a 3,1 kg. Se analizaron cuatro cuadrantes de las muestras de 12 animales. Las fibras tipo IIB ocuparon la mayor superficie, en comparación con los otros tipos de fibras. Los diámetros y volúmenes relativos de las fibras fueron similares entre los diferentes tipos identificados por NADH-TR. No se observaron diferencias significativas en el número de vasos por fibra, entre los diferentes tipos de fibras. El área ocupada por el endomisio fue la superficie más pequeña entre los parámetros analizados. Estos resultados demostraron la intensa actividad de este músculo en la arquitectura facial del animal. Sin embargo, el predominio de las fibras tipo II, de baja oxidación, indica más propensión a la fatiga muscular. El presente hallazgo pueden contribuir al estudio de las miopatías con la participación de este músculo.

External location of the buccinator muscle to facilitate electromyographic analysis

Electromyography is frequently used to measure the activity of masticatory muscles. It requires the precise setting of the electrodes, which demands the accurate location of the muscle to be evaluated. The purpose of this study was to investigate the accuracy of an external method to locate the buccinator muscle. Fifteen human cadavers were evaluated and planes were determined on the face using anatomic landmarks. An angle (a) was obtained at the intersection of these planes on the central point of buccinator muscle and measured with a protractor. The value of the angle allows locating the central point of buccinator muscle based on anatomic landmarks on the face. Statistical analysis of the collected data indicated an angle of 90º with 95 percent reliability, thus proving the efficacy of the proposed method.

A eletromiografia é frequentemente utilizada para mensurar a atividade dos músculos mastigatórios. Esta análise exige a colocação precisa dos eletrodos, o que requer a localização exata do músculo a ser avaliado. O objetivo do presente estudo foi investigar a acurácia de um método externo para localização do músculo bucinador. Quinze cadáveres humanos foram avaliados e planos foram determinados na face utilizando-se pontos de referência anatômicos. Um ângulo (a) foi obtido na interseção desses planos no ponto central do músculo bucinador e foi medido com um transferidor. O valor do ângulo permite localizar o ponto central do músculo bucinador baseado nos pontos de referência anatômicos da face. A análise estatística dos dados obtidos indicou um ângulo de 90º com 95 por cento de confiabilidade, confirmando dessa forma a eficácia do método proposto.