Maximum bilateral bite strength and RMS EMG for the diagnosis of myogenic TMD

Aim: The study aimed to evaluate the accuracy of the maximum bilateral molar bite force and the Root Mean Square (RMS) Electromyography (EMG) index of the masticatory muscles in the maximum bilateral molar bite (MMBMax) of women with myogenic Temporomandibular Disorder (TMD) and asymptomatic. Methods: This is a cross-sectional study, composed of 86 women allocated to the TMD Group (n=43) and Control Group (n=43) diagnosis through the Diagnostic Criteria for Temporomandibular Disorders. The maximum bilateral molar bite force was evaluated using a bite dynamometer and the RMS EMG index of the masticatory muscles (anterior temporalis, masseter) during 5 seconds of the MMBMax task. Student t-test was used for data comparison between accuracy of the bite force and RMS EMG of masticatory muscles during the MMBMax. Results: The maximum bilateral molar bite force showed high accuracy (AUC=0.99) for the diagnosis of women with myogenic TMD and asymptomatic women, and the RMS EMG index evaluated during the MMBMax showed a moderate level of accuracy for all masticatory muscles (AUC=0.70 to 0.75). Conclusion: The bilateral bite dynamometer with a surface EMG during bilateral bite can be used to diagnose TMD in young women

Normalization of the electromyographic signals of masticatory muscles during non-habitual chewing activity

There is no consensus on the most appropriate method for normalizing electromyography (EMG) signals from masticatory muscles during isotonic activity. Aim: To analyze the best method for data processing of the EMG signal of the masticatory muscles during isotonic activity (non-habitual chewing), comparing raw data and different types of normalization. Methods: This is a cross-sectional study. Women aged between 18 and 45 years were selected. Anthropometric data were collected (age, height, body mass index ­ BMI, masticatory preference) as well as EMG signal (root mean square ­ RMS) data for the anterior temporal and masseter bilaterally, and for the suprahyoid muscles, during isotonic (non-habitual chewing) and isometric tasks. EMG data were processed offline using Matlab® Software. The normalization of the EMG signal was carried out using the 2nd masticatory cycle, chosen at random, of the 20 cycles collected, the maximum RMS value, and the maximum voluntary contraction (MVC). To analyze the best method of data processing for the isotonic data, the coefficient of variation (CV) was calculated. Descriptive data analysis was adopted, using the mean and standard deviation. ANOVA with repeated measures was used to detect significant differences between the methods of normalization. Statistical significance was set at 5% (α<0.05). Results: The final sample of this research was composed of 86 women. The volunteers presented an average age of 27.83±7.71 years and a mean BMI of 22.85±1.91 Kg/m2. Regarding masticatory preference, 73.25% reported the right side, and 26.75% the left side. Considering the comparison between the methods, the %CV measure of the 2nd cycle showed the lowest variation coefficient during biting for all the muscles from the raw data, RMS Max, and MVC (p=0.001, p=0.003, and p=0.001 respectively). Conclusion: In conclusion, for non-habitual chewing activity, the results of this study recommend data processing using normalization with the second cycle during chewing

Strength of scapular elevation in women with TMD and asymptomatic women - a cross-sectional study

Temporomandibular disorder (TMD) is recognized for its high prevalence, presenting characteristic signs and symptoms. Cervical spine pain is present in 70% of diagnosed TMD cases. Aim To verify if women with TMD present changes in isometric muscle strength in the scapula elevation. Methods This is an observational, cross-sectional study. Thirty-five women, aged 22.89±2.04 years, were divided into the TMD group (TMDG), diagnosed with TMD according to the DC/TMD, and control group (CG), with asymptomatic individuals. The volunteers accessed a online link by the smartphone in order to answer questions on personal data, the Fonseca Anamnestic Index (FAI), Neck Disability Index (NDI), and Masticatory preference. In all participants, evaluation of the force of the scapula elevation muscles was performed, using a load cell model MM-100 (Kratos® SP, Brazil). Data were analyzed descriptively using the maximum, mean, and standard deviation and a two-way ANCOVA test was applied for all variables. A significance level of 5% was considered. Results There were no statistically significant differences between the TMDG and CG for the maximal and mean muscle strength of scapular elevation. There were statistically significant differences in FAI (p <0.001*) between the CG and the TMDG. Conclusion Based on the results, it was not possible to confirm the hypothesis that women diagnosed with TMD present lower isometric strength during scapular elevation (right/left).

Comparison of instruments used to select and classify patients with temporomandibular disorder / Avaliação de instrumentos utilizados para selecionar pacientes com disfunção temporomandibular

The aim of the present study was to identify the relationship among instruments used to screen and diagnose temporoman dibular disorders (TMD). A retrospective study was conducted using medical records of patients with temporomandibular disorder who had visited the institution for initial assessment between January and December 2015. Medical history and physical examination data were collected, particularly those focusing on the diagnosis of TMD and TMJ (temporomandibular joint) function. The following instruments were used to assess the severity of the TMD signs and symptoms: the Fonseca Anamnestic index (FAI), the Helkimo index (HI), the American Association of Orofacial Pain Questionnaire (AAOPQ) and the Jaw Symptom & Oral Habit Questionnaire (JSOHQ). Thirtyeight patient records were included, with prevalence of women (84.6%) and mean age 37.42 ± 14.32 years. The patients who were classified as having severe TMD by the FAI exhibited more positive responses on the AAOPQ (6.25 ±1.42; oneway ANOVA F=15.82), with a statistically significant difference when compared to patients with mild TMD (3.0 ±1.22; p<0.01). A positive correlation (r=0.78; p<0.01) was found between the number of positive responses on the AAOPQ and the sum of the JSOHQ scores. Patients who were classified with severe TMD on the FAI exhibited higher scores on the JSOHO (18.58 ±4.96/ oneway ANOVA F=14.43), with a statistically significant difference when compared to patients with moderate (12.08 ±5.64; p<0.01) and mild TMD (7.46 ±4.89; p<0.01). Conclusion: In the study sample, there was consistency among the instruments used to differentiate patients with severe and mild TMD. The selection of instruments should be rational, in order to improve the quality of the results (AU)

O objetivo deste estudo foi identificar a relação entre os instrumentos utilizados para selecionar e diagnosticar os pacientes com disfunção temporomandibular (DTM). Foi realizado um estudo retrospectivo utilizando prontuários odontológicos de pacientes atendidos devido a dor e disfunção na articulação temporomandibular, que haviam procurado a instituição para uma avaliação inicial entre janeiro e dezembro de 2015. Foram coletados dados da história médica e do exame físico, particularmente aqueles que se concentraram no diagnós tico de DTM. Os seguintes instrumentos foram utilizados para avaliar a gravidade dos sinais e sintomas da DTM: o índice anamnésico de Fonseca (FAI); O índice Helkimo (HI); o questionário da Associação Americana de Dor Orofacial (AAOPQ) eo Questionário de Sintomas e Hábitos Orais (JSOHQ). Foram incluídos trinta e oito prontuários de pacientes, com prevalência de mulheres (84,6%) e idade média de 37,42 ± 14,32 anos. Os pacientes que foram classificados com DTM severa pela FAI apresentaram maior número de respostas positivas no AAOPQ (6,25 ± 1,42; ANOVA F = 15,82), com diferença estatisticamente significativa em comparação com pacientes com DTM leve (3,0 ± 1,22; p < 0,01). Foi encontrada uma correlação positiva (r = 0,78; p <0,01) entre o número de respostas positivas no AAOPQ e a soma dos escores no JSOHQ. Os pacientes que foram classificados com DTM severa na FAI exibiram pontuações mais altas no JSOHO (18,58 ± 4,96 / ANOVA F = 14,43), com diferença estatisticamente significativa quando comparados a pacientes com DTM média (12,08 ± 5,64; p <0,01) e leve (7,46 ± 4,89; p <0,01). Na amostra estudada, houve congruência entre os instrumentos utilizados para diferenciar os pacientes com DTM grave e leve. A seleção de instrumentos deve ser racional, a fim de melhorar a qualidade dos resultados (AU)

Preservação da crista alveolar através da utilização de membrana densa de politetrafluoretileno / Preservation of the alveolar crest through the use of polytetrafluoroethylene dense membrane

O processo de remodelação óssea que inicia-se após a extração de um dente pode dificultar a reabilitação através de implantes dentários. Nesse sentido, a técnica de regeneração óssea guiada (ROG), com o uso de membrana não reabsorvível, busca minimizar estes efeitos, favorecendo a cicatrização do alvéolo e diminuindo a necessidade de enxertos ósseos. Sendo assim, o objetivo deste trabalho foi avaliar a utilização da membrana densa de politetrafluoretileno (d-PTFE) em alvéolos pós-extração. Para isso, 8 pacientes que foram submetidos à remoção de elemento dentário receberam em seus alvéolos a colocação da membrana d-PTFE. A mesma foi posicionada sobre o alvéolo imediatamente após a extração e deixada no local por 21 dias. Para avaliar a preservação do rebordo alveolar, tomografias foram realizadas no pré-operatório e no pós-operatório de 90 dias. Os resultados mostraram uma efetiva preservação do rebordo alveolar proporcionado pelo uso da membrana. A perda óssea em espessura dos alvéolos foi de apenas 0,32 mm, em média. Já a perda óssea em altura foi de 0,79 mm, em média. Oito implantes foram instalados, sendo que nenhuma complicação ou perda de implantes foi observada. A membrana de PTFE denso mostrou-se efetiva na manutenção da arquitetura alveolar, minimizando a perda óssea em altura e espessura (AU).

The process of bone remodeling that begins after the extraction of a tooth can make rehabilitation difficult through dental implants. In this sense, the technique of guided bone regeneration (ROG), with the use of a non-resorbable membrane, seeks to minimize these effects, favoring healing of the alveolus and reducing the need for bone grafts. Therefore, the objective of this work was to evaluate the use of polytetrafluoroethylene dense membrane (d-PTFE) in post-extraction alveoli. For this, 8 patients who were submitted to tooth removal, received in their alveoli the placement of the d-PTFE membrane. It was placed on the alveolus immediately after extraction and left in place for 21 days. To evaluate the preservation of the alveolar ridge, CT scans were performed preoperatively and postoperatively for 90 days. The results showed an effective preservation of the alveolar ridge provided by the use of the membrane. The bone loss in the alveoli thickness was only 0.32 mm on average. The bone loss in height was 0.79 mm on average. Eight implants were installed, and no complications or loss of implants were observed. The dense PTFE membrane was effective in maintaining the alveolar architecture, minimizing bone loss in height and thickness (AU).

Potential donor sites of the parietal for bone grafting and its relationship to the cephalic index / Sitios donantes potenciales del hueso parietal para injerto óseo y su relación con el índice cefálico

The purpose of the present study was to chart the thickness of the parietal bone and establish its relationship with the cephalic index and sex aiming at improving current knowledge and guidance for obtaining calvarial bone auto-graft material. Both left and right parietal bones of 150 skulls of adult human cadavers classified as either dolicho-, meso-, or brachicephalic, and as either male or female had their thickness measured at 3 levels ­ superior (S), middle (M) and inferior (I) ­ and at 3 points ­ anterior (a), middle (m) and posterior (p) ­ in each level, all evenly laid out. No relevant differences in thickness whether comparing sex or cephalic index was evidenced. The thickest measurements were found at points located at superior and middle levels in middle and posterior positioning ­ Sm, Sp, Mm and Mp ­ with median values ranging from about 5.5mm to 7.13mm. At inferior level and posterior positioning, thickness median values ranged from 4.71 to 5.84mm. Safer harvesting of bone graft material occurs in Sm, Sp, Mm and Mp areas of the parietal bone. Only exceptionally should Ip domain be used, whereas Sa, Ia and Im regions should be considered non-donor sites.

El propósito del estudio fue medir el grosor del hueso parietal y establecer su relación con el índice cefálico y el sexo, con el objetivo de mejorar el conocimiento actual y la orientación para el auto-injerto de material óseo. Fueron estudiados huesos parietales, tanto izquierdos como derechos, de 150 cráneos de cadáveres humanos adultos, de hombres y mujeres, clasificados como dolico-, meso- o braquicefálico; el espesor fue medido en 3 niveles: superior (S), medio (M) e inferior (I) - y en 3 puntos - anterior (a), medio (m) y posterior (p) - en cada nivel, todas uniformemente establecidas. No se observaron diferencias relevantes en el grosor a nivelrespecto del sexo o el índice cefálico. Las mediciones más gruesas se encontraron en los puntos situados en los niveles superior y medio, y en posiciones medias y posteriores - Sm, Sp, Mm y Mp - con valores medianos que oscilaban entre aproximadamente 5,5 mm y 7,13 mm. En el nivel inferior y posicionado posterior, los valores medianos del espesor oscilaron entre 4,71 y 5,84 mm. La recolección más segura del material de injerto óseo ocurre en las áreas Sm, Sp, Mm y Mp del hueso parietal. Sólo excepcionalmente se debe utilizar el dominio Ip, mientras que las regiones Sa, Ia e Im deben considerarse sitios no donantes.

Surgical management of mandibular ameloblastoma and immediate reconstruction with nonvascularized bone graft and hyperbaric oxygen therapy / Tratamiento quirúrgico de ameloblastoma mandibular y la reconstrucción inmediata con injerto oseo libre y terapia con oxígeno hiperbárico

Extensive resection of tumor often results in bone and soft tissue defects that cause functional and esthetic consequences. The reconstructive surgery is extremely important for the rehabilitation of these patients. The purpose of this study is to report on the use of Hyperbaric Oxygen therapy (HBO) in the case of a large ameloblastoma treated with segmental resection and reconstructed immediately with nonvascularized bone graft (NVBGs) from iliac crest. A 41-year-old woman was referred to our department because of paresthesia of the inferior alveolar nerve and history of swelling in the molar and ramus region of the left mandible. Panoramic radiograph depicting well-defined multilocular radiolucency extending from second pre-molar region to the left ramus region. An incisional biopsy confirms the diagnosis of solid ameloblastoma. The treatment of choice was segmental mandibular resection and immediate mandibular reconstruction using NVBGs from iliac crest, followed by removal of internal fixation and placement of dental implants with immediate loading. The patient received preoperative HBO (a 90-min session at 2.2-2.4 atmospheres, five times per week for two weeks, for a total of up to 10 sessions). Postoperative HBO (10 further 90-min sessions) was administered within 2weeks. The patient received rehabilitation with a mandibular implant-supported fixed complete dental prosthesis. The present study showed successful management of mandibular ameloblastoma that associated extensive surgery, immediate reconstruction with NVBGs from iliac crest, hyperbaric oxygen therapy and dental implants. These combined procedures allowed removal of lesion and reestablishment of mandibular contour and function.

La resección extensa de un tumor a menudo da lugar a defectos del hueso y de los tejidos blandos, que causan consecuencias funcionales y estéticas. La cirugía reconstructiva es extremadamente importante para la rehabilitación de estos pacientes. El propósito de este estudio fue informar sobre el uso de la terapia de oxígeno hiperbárico (HBO) en un caso de un ameloblastoma de gran tamaño, tratado con resección segmentaria y reconstruido inmediatamente con injerto óseo no vascularizado (IONV) de la cresta ilíaca. Una mujer de 41 años fue derivada a nuestro servicio por parestesia del nervio alveolar inferior e historia de hinchazón en la región molar y ramina de la mandíbula izquierda. Radiografía panorámica que muestra una radiolucencia multilocular bien definida que se extiende desde la segunda región pre-molar hasta la región de la rama izquierda. Una biopsia incisional confirma el diagnóstico de ameloblastoma sólido. El tratamiento de elección fue la resección mandibular segmentaria y la reconstrucción mandibular inmediata mediante IONV de cresta ilíaca, seguido de la eliminación de la fijación interna y la colocación de implantes dentales con carga inmediata. La paciente recibió OHB preoperatoria (una sesión de 90 minutos a 2.2-2.4 atmósferas, cinco veces por semana durante dos semanas, para un total de hasta 10 sesiones). La OHB postoperatoria (10 sesiones adicionales de 90 minutos) se administró en 2 semanas. La paciente recibió rehabilitación con una prótesis dental fija con implante mandibular. El presente estudio mostró un manejo exitoso del ameloblastoma mandibular asociado a una cirugía extensa, reconstrucción inmediata con IONV de cresta ilíaca, oxigenoterapia hiperbárica e implantes dentales. Estos procedimientos combinados permitieron la extirpación de la lesión y el restablecimiento del contorno y la función mandibular.

Mandibular foramen location and lingula height in dentate dry mandibles, and its relationship with cephalic index / Localización del foramen mandibular y altura de la língula mandibular en mandíbulas dentadas secas, y su relación con el índice cefálico

The mandibular foramen and its lingula is a major landmark when administering anesthetic or performing surgical procedures. The objective of this study was to determine whether the topological features of the mandibular foramen (MF) and lingula varied in mandibles from skulls of different cephalic indexes. The location of the mandibular foramen referred to the longitudinal borders of the mandibular ramus (MR), height of the foramen (Hf) referred to the occlusal line of the second molar, and the height of the lingula (Hl) were determined in a total of one hundred and five dry mandibles from skulls identified as dolicho- meso- and brachycephalic. On average MF in brachycephalic mandibles was closest to the anterior border of MR. Hf in brachy-, meso- and dolichocephalic mandibles were -0.22 mm, -4.04 mm and -4,01mm, respectively. The lingula in brachycephalic specimens was considerably shorter (0.78 mm) than in dolichocephalic ones (1.84 mm). Inferior alveolar nerve block should be carried out using shorter needles, inserting it 4mm above the occlusion level of the molar teeth. The ramus of brachicephalic mandibles were significantly less wide those of dolicho- and mesocephalic ones. If the height of the lingula is to be used as a reference to judge the level of the medial horizontal cut to carry out sagittal split ramus osteotomy, special attention should be given to the patient's cephalic index.

El foramen mandibular y la língula son los puntos anatómicos más importantes a considerar en la administración de anestesia troncular o la realización de procedimientos quirúrgicos en la mandíbula. El objeivo fue determinar si las características topológicas del foramen mandibular (FM) y la língula mandibular presentan variaciones en las mandíbulas de cráneos con diferentes índices cefálicos. Fueron utilizados 105 mandíbulas secas, pertenecientes a cráneos identificados como dolico, meso y braquicéfalos. En cada caso, se relacionaron la ubicación del FM con los márgenes longitudinales de la rama mandibular (RM) y la altura del foramen (Af) con la línea oclusal del segundo molar. Además, se determinó la altura de la língula (Al). En promedio, el FM de mandíbulas braquicefálicas se encontró más cerca del margen anterior de la RM. La Af en mandíbulas braqui, meso y dolicocéfalas fue de -0,22 mm, -4,04 mm y -4,01 mm, respectivamente. La língula mandibular en muestras braquicefálicas, fue considerablemente más corta (0,78 mm) que en las dolicocéfalas (1,84 mm). El bloqueo del nervio alveolar inferior debe llevarse a cabo usando agujas cortas, insertándolas 4 mm por encima del nivel de oclusión de los dientes molares. La rama de las mandíbulas braquicefálicas fueron significativamente menos anchas que en cráneos dolico y mesocefálicos. Si la altura de la língula mandibular se utilizará como referencia para determinar el nivel del corte medial horizontal para realizar la osteotomía sagital de la rama mandibular, se debe dar especial atención al índice cefálico del paciente.

Variation in the repair of a rib graft used for mandibular reconstruction after 20 years / Variación en la reparación de un injerto costal utilizado para reconstrucción mandibular después de 20 años

Mandibular reconstruction has been used in the last 100 years as a safe, effective and stable technique. Various types of grafts have been used, including the autogenous rib graft; the normal repair of this type of graft has been defined in some studies although some observations have been made indicating low predictability of the growth of this bone. The aim of this study was to report the case of a patient with a rib graft for mandibular reconstruction where after 20 years cartilaginous tissue was observed exclusively in the absence of bone tissue. A 61-year-old female patient presented in the Oral and Maxillofacial Surgery Service for dental implants. The patient had a history of 4 previous mandibular reconstructions; imaging showed no alterations to the normal evolution of a graft. However, the intraoral access contained softer tissue than the normal bone, and thus the implant installation was abandoned. Histopathological analysis revealed the formation of collagenous tissue and cartilage, chondrocytes island conditions characteristic of cartilaginous tissue in the absence of mineralization and cancellous bone. This led to the conclusion that repair conditions can vary based on specific and general factors as yet under discussion.

La reconstrucción mandibular ha sido utilizada en los últimos 100 años como una técnica segura, eficaz y estable. Diversos tipos de injertos se han utilizado siendo el auto trasplante de hueso costal uno de ellos; la normal reparación de este tipo de injertos ha sido definida en algunas investigaciones aunque se han realizado otras observaciones indicando baja predictibilidad del crecimiento de este hueso; el objetivo de esta investigación es reportar un caso de una paciente portadora de injerto costal para reconstrucción de mandíbula donde después de 20 años se observó exclusivamente tejido cartilaginoso en ausencia de tejido óseo. Una paciente del sexo femenino, 61 años se presentó al Servicio de Cirugía Oral y Maxilofacial para ser tratada con implantes dentales; la paciente presentaba historia de 4 reconstrucciones mandibulares previas; los estudios de imagen se presentaban sin alteraciones a la condición normal de la evolución. Sin embargo, al acceso intraoral se observó un tejido más blando que el hueso normal, abortándose la instalación del implante. El análisis histopatológico reveló la formación de tejido colágeno y cartílago, condrocitos en lagunas y condiciones características de tejido cartilaginoso en ausencia de mineralización y trabeculado óseo.Se concluye que las condiciones de reparación pueden variar en base a factores específicos y generales aun en discusión.

Mandibular condyle repair after partial condylectomy in patients with active condylar hyperplasia / Reparación de cóndilos mandibulares después de condilectomía parcial por hiperplasia condilar activa

The different aspects of unilateral condylar hyperplasia have been studied and continue to be controversial; nevertheless, treatment based on condylectomy has been established as part of the working protocol. The aim of this investigation was to identify the bone repair observed in surgically treated condyles after 1 year using cone beam computed tomography (CBCT). Nine subjects were included in this study (6 female and 3 male) with an average age of 18.5 years. They had been diagnosed with active unilateral condylar hyperplasia using SPECT, clinical follow-up of progressive facial asymmetry and CBCT. Patients underwent exclusive condylectomy surgery with a piezoelectric system without disc replacement, orthognatic surgery or any other type of adjunct surgical procedure. Later, they were treated orthodontically for dental compensation or as preparation for orthognatic surgery. A CBCT was performed in the first postoperative month and after 1 year from the surgery to analyze variables. The CBCT at 1 month showed a clear and distinct slice of the condyle without defects or irregularities; the distance from the condylar remnant to the articular fossa reached 8.5 mm in the most extreme case. After 1 year, condylar bone remodeling was observed, with areas of lateral and superior curvature and characteristics of normal condyles, with cortical bone present and a maximum distance of 4.5 mm from the condylar fossa. In conclusion, condylar repair and remodeling can be obtained in these types of surgeries and the morphology of resected condyles after 1 year is quite close to normal macroscopic anatomy.

La hiperplasia condilar unilateral ha sido estudiada en diferentes aspectos y continua siendo controversial; aun así, el tratamiento en base a condilectomía se establece como parte del protocolo de trabajo. El objetivo de esta investigación es reconocer la reparación ósea observada en cóndilos operados después de 1 año mediante tomografía computadorizada cone beam (TCCB). Nueve sujetos fueron incluidos en este estudio (6 sexo femenino y 3 sexo masculino) con una edad promedio de 18,5 años; en ellos se realizó el diagnóstico de hiperplasia condilar unilateral activa mediante estudio de SPECT, seguimiento clínico de la asimetría facial progresiva y TCCB. Se realizó la cirugía de condilectomía exclusiva con sistema piezoeléctrico sin reposición de disco, cirugía ortognática u otro tipo de procedimiento quirúrgico adjunto; posteriormente, los pacientes fueron tratados ortodoncicamente para compensación dentaria o para preparación previa a cirugía ortognática. Se realizó TCCB dentro del primer mes postquirúrgico y después de 1 año de realizada la cirugía para análisis de variables. Se observó en la TCCB de 1 mes un corte nítido y neto del cóndilo, sin defectos o irregularidades; la distancia desde el remanente condilar hasta la fosa articular llegó hasta 8,5 mm en el caso máximo. Después de 1 año, se observo remodelación ósea condilar, con áreas de curvatura lateral y superior características de cóndilos normales, con presencia de hueso cortical y con una distancia máxima de 4,5 mm desde la fosa condilar. Se puede concluir que la reparación y remodelación condilar es viable de obtenerse en este tipo de cirugías y que la morfología de cóndilos resecados después de 1 año es bastante próxima de la anatomía macroscópica normal.

Photoelastic Analysis of Two Maxillary Protocols Using Zygomatic Implants / Análisis Fotoelástico de Dos Protocolos Maxilares con Uso de Implantes Cigomáticos

The aim of this study was to analyse the in vitro the stress distribution in craniofacial structures around zygomatic implants. Synthetic polyurethane skulls replicas were used as templates for installation of standard and zygomatic implants performing two techniques using rehabilitation with using one zygomatic implant in the right and left side in combination with 2 and 4 standard implants in the anterior maxilla (group 1 and group 2). The skull replicas of photoelastic resin were subjected to photoelastic analysis after linear loading using an Instron 4411 servohydraulic mechanical testing, with a 2 mm displacement. The stress distribution showed the fringes with concentration in the body and the frontal process of zygomatic bone. In the case of model 1, higher concentrations of stress were found around the standard and zygomatic implants and surrounding bone. Under this condition, the rehabilitation with 2 zygomatics implants and 4 standard implants (group 2) provided the most favorable behavior.

El objetivo de este estudio fue analizar el estrés in vitro y la distribución de tensiones en la estructura craneofacial a partir de los implantes cigomaticos. Réplicas de cráneo de poliuretano fueron usados como modelos para la instalación de implantes cigomáticos estándar utilizando dos modelos de distribución de implantes. Estos modelos fueron usados como modelos utilizando 1 implante en cada lado con dos o cuatro implantes convencionales en la región anterior maxilar (grupo 1 y grupo 2); posteriormente, se realizó una carga compresiva unilateral en la máquina Instrom 4411 utilizando 2 mm de desplazamiento máximo. La distribución de estrés se concentró principalmente en la región de cuerpo de hueso cigomático y en la región frontal del proceso cigomático; el modelo 1, con dos implantes convencionales, mostró mayor distribución de estrés en la región cigomática al comparase con el grupo 2; bajo estas condiciones, se concluye que la distribución con cuatro implantes convencionales entrega mejores condiciones de distribución de tensiones.

Morfología ósea de sínfisis mandibular: estudio piloto / Osseous morphology in the mandibular symphysis: a pilot study

El objetivo de este estudio fue evaluar la relación de tejido óseo cortical y esponjoso en el sector anterior de la mandíbula. Se seleccionaron 14 sujetos de ambos sexos para realizar el estudio piloto de este protocolo; en todos los sujetos se realizó un estudio con tomografía computarizada de haz cónico para realizar análisis morfométrico en base a la posición de los dientes canino, incisivo lateral e incisivo central de ambos lados; se analizó la distancia vertical desde el ápice dentario hasta el punto más inferior del margen mandibular y se analizó la distancia anteroposterior en dos niveles inferiores del ápice (5 mm y 10 mm); en estos niveles se identificó el tamaño de hueso cortical y el tamaño de hueso esponjoso. Se observó que el hueso cortical es de mayor tamaño en la cortical lingual que la cortical bucal, con casi 1 mm de diferencia; el hueso esponjoso fue similar a la sumatoria de ambos huesos corticales (5 mm aproximadamente) en las áreas evaluadas. Se concluye que el hueso cortical es menor en el sector bucal al compararse con el lingual; la distancia vertical desde el ápice dentario hasta el margen mandibular fue de 16,5 y 21,05 mm.

The aim of this research was to evaluate the relation between the cortical and cancellous bone in the anterior area of the mandible. Were selected 14 subjects, male and female, to make the pilot study with this protocol; in all of them was realized a cone beam computed tomography to make a morphometric analysis in agreed with de canine, lateral incisor and central incisor of the both, right and left, side. Was analyzed the distance between the apex of the tooth to the inferior point of the cortical bone in the marginal area and in 5 and 10 mm lower of the dental apex. In these levels were identified the cortical bone size and cancellous bone size. Was observed that the cortical bone is thicker in the lingual side than the buccal side (1 mm diference approximately); the cancellous bone size is like the lingual and buccal cortical size (5 mm approximately) in the evaluated areas. Its concluded that the buccal cortical bone is lower than lingual cortical bone; the vertical distance between the apex and the basilar area is close to 16.5 and 21.05 mm.

Analise epidemiol¢gica do cisto ¢sseo simples por meio do tratamento conservador / Epidemiological analysis of simple bone cyst by conservative treatment

O Cisto àsseo Traum tico (COS) ‚ uma lesÆo rara, que tem alta incidˆncia na mand¡bula, principalmente na segunda d‚cada de vida. A descoberta do COS ocorre durante os exames de rotina, sendo assintom tica. A etiologia do COS geralmente encontra-se associada a algum tipo de trauma local, sem rela‡Æo causal com gˆnero ou ra‡a. O tratamento desta lesÆo ocorre na grande maioria dos relatos por meio de explora‡Æo cir£rgica, revelando-se eficaz e seguro. O objetivo deste estudo foi avaliar retrospectivamente os casos de COS, tratados entre janeiro de 1999 a julho de 2011. Foram avaliados 10.543 prontu rios, onde 12 pacientes apresentaram COS. Todos os casos ocorreram em pacientes que estavam na segunda d‚cada de vida, com m‚dia de idade de 15,2 anos. A mand¡bula estava envolvida em 100% dos casos, com elevada incidˆncia na s¡nfise (55%), seguido pelo corpo (36%) e ramo da mand¡bula (9%). Seis pacientes relataram a hist¢ria pregressa de trauma (2-9 anos) antes do diagn¢stico da lesÆo. Todos os pacientes foram submetidos … bi¢psia incisional associada … explora‡Æo cir£rgica da cavidade c¡stica, o que representou o tratamento definitivo. O tempo m‚dio de proserva‡Æo foi de 35,7 meses. No per¡odo de acompanhamento (7 a 85 meses), nÆo foi observada recidiva da lesÆo. O tratamento por meio de cirurgia explorat¢ria, realizada no momento da bi¢psia, foi eficaz em todos os casos deste estudo

The simple bone cyst (SBC) is a rare asymptomatic injury diagnosed during routine examinations. The etiology of SBC is usually associated with a local trauma, with no relation with gender or race. The treatment through surgical exploration has proved to be effective and safe. The goal of this study was to evaluate retrospectively the cases of SBC, treated between January/1999 to July/2011. The study evaluated 10.543 clinical handbooks, in which 12 patients presented SBC. In all cases patients were in the second decade of life, with mean age of 15.2 years. Mandible was involved in 100% of the cases, with high incidence on the symphisis (55%), followed by body (36%), and mandibular ramus (9%). Six patients reported trauma (2-9 years) prior to the diagnosis. All patients were submitted to an incisional biopsy associated to a surgical exploration of the cystic cavity, that represented the definitive treatment. The average time of proservation was 35.7 months. In the follow-up period (7 to 85 months) was not observed any recurrence. The treatment through exploratory surgery, carried through the moment of the biopsy, was effective in all cases

Utilização clínica do Lumina-Porous para enxerto ósseo heterógeno em seio maxilar: estudo preliminar com relato de dois casos clínicos / Clinical use of Lumina-Porous heterologous graft in the maxillary sinus:a preliminary study with two case reports

A reabilitação de pacientes edêntulos com implantes dentários depende de adequado suporte ósseo, a região posterior de maxila muitas vezes apresenta quantidade de tecido ósseoinsuficiente, sendo necessária cirurgia para levantamento do seio maxilar e utilização de um enxerto. Existem diversos materiais disponíveis, de forma que a escolha deve se basear em características do paciente e do material. O objetivo deste trabalho é relatar dois casos clínicos em quefoi realizada cirurgia para levantamento de seio maxilar bilateralmente, utilizando os substitutos ósseos Bio-Oss® e Lumina-Porous®. Dois pacientes com edentulismo total de maxila foram submetidos à cirurgia de levantamento de seio maxilar, bilateralmente, sendo empregados os substitutos ósseos Bio-Oss® no lado direito, e Lumina-Porous® no lado esquerdo. Depois de seis meses,a partir de um planejamento protético prévio, foi realizada a instalação de oito implantes para reabilitação com prótese fixa maxilar. Não foram observadas diferenças quanto às complicações trans e pós-operatórias ou travamento inicial dos implantes. Ambos os materiais apresentaram manutenção do volume adquirido durante a cirurgia. Apesar da utilização do Bio-Oss estar bem estabelecida na literatura, o Lumina-Porous não apresenta o mesmo nível de evidência científica,de forma que são necessários mais estudos sobre esse material.

Oral rehabilitation of edentulous patients with dental implants depends on proper quantity of bone. The posterior maxilla often has an insufficient amount of bone that require sinus augmentation surgery associated with bone graft. There are several types of material available and which can be used as bone grafts. The choice of material should be based on patient’s and material’s characteristics. Objective: The objective of this study is to report two cases in which sinus augmentation bilateral surgery was performed using two bone substitutes: Bio-Oss™ and Lumina-Porous™. Methods: Two patients with edentulous maxilla underwent surgery for maxillary sinus augmentation using Bio-Oss™ on the right side and Lumina-Porous™ on the left side. Six months later, after previous implant planning, eight implants were surgically installed for maxillary rehabilitation with fixed denture. Results: No differences were found regarding complications duringand after surgery or insertion torque of dental implants. Both types of material showed maintenance of the acquired bone volume as a result of surgery. Although the use of Bio-Oss™ is wellestablished in the literature, this is not true for Lumina-Porous™. This heterologous graft does not present the same level of scientific evidence, therefore, additional studies are warranted to further investigate this material.

Pharyngeal airway space in subjects with class II and class III facial deformities / Espacio de la vía aérea faríngea en sujetos con deformidad facial clase II y clase III

Facial deformities are related to morphological differences and the mandible position shows differences in maxillomandible relation. The aim of this research was to compare the pharyngeal airway space (PAS) in subjects with class II and class III facial deformities We included 28 adult subjects with skeletal characteristics associated to class II or class III according to the SNA angle and dental overjet; subjects with facial asymmetry and other facial deformities and subjects with facial trauma or facial surgery history were excluded. Cone beam computed tomography was realized (CBCT) to asses the nasopharynx, oropharynx, hypopharynx, as well as the distance measured between the mandible genial spine and hyoid bone; data analysis were realized by descriptive analysis and statistical analysis using t test with 0.05 to show statistical differences. Class II subjects presented minor values in all of the measurements; in the oropharynx and the hypopharynx we observed the most important differences, with nasopharynx showing statistically significant differences (p<0.05). In conclusion class II subjects presented a minor pharyngeal airway space and it is suggested that this information should be used in the diagnosis process and prior to surgical treatment.

Las deformidades faciales son asociadas a diferencias en la posición mandibular evidenciando diferencias en la relación maxilomandibular. El objetivo de esta investigación fue comparar el espacio aéreo faríngeo en sujetos con deformidad facial clase II y clase III. Se incluyeron 28 sujetos con características esqueletales asociadas a clase II o clase III seguidos de la evaluación del angulo SNA y el resalte dentario; se excluyeron los sujetos con asimetría facial y otras deformidades faciales y sujetos con historia de trauma facial o historia de cirugía facial; se realizó la tomografía computadorizada cone beam para evaluar el área de nasofaringe, orofaringe, hipofaringe y la distancia entre la espina geni mandibular y el hueso hioides; los datos se analizaron con estadística descriptiva y la prueba t usando un valor de 0,05 para establecer significancia estadística. Se observó que los sujetos de clase II presentaron valores menores a los sujetos clase III en todas las mediciones realizadas; en el área de orofaringe e hipofaringe se observaron las diferencias mas importantes, estadísticamente significativas (p<0,05). Se puede concluir que los sujetos con deformidad facial clase II presentan un espacio de vía aérea faríngea más estrecho y se sugiere que este temática sea resuelta en la etapa de diagnóstico previo a la selección de tratamientos quirúrgicos o no quirúrgicos.

Facial soft tissue in subjects with class II and class III facial deformities: preliminary results / Tejido blando facial en sujetos con deformidad facial clase II y clase III: resultados preliminares

Class II and class III skeletal anomalies require treatments that are both esthetic and functional, so the purpose of this investigation was to study the relationship between facial soft and hard tissues of patients with class II and class III deformities in the lower third of the face. A descriptive study was designed which included class II subjects with a SNB angle less than 78 and class III with a SNA angle less than 80. The soft tissue width was analyzed in relation to the Pg point, A point, B point, and upper and lower incisor cervical points. The naso-labial angle and interincisal angle were also analyzed. The studies were done using cone beam computerized tomography and analyzed with the software Simplant O&O (Materialise, Belgium). The results revealed similarities in the measurements of the facial width soft tissues with differences of less 1 mm in the Pg point, A point, B point, upper incisor point; the greatest differences were observed between the two groups in thelower incisor cervical point, with almost 5 mm difference in tissue size. The naso-labial angle also presented differences between the two groups, being more closed in the class III than in the class II subjects (approximate difference of 6). It can be concluded that there are minimal differences in the soft tissue width in class II and class III subjects; other parameters can be analyzed to search for differences that influence treatment planning and strategies for these patients.

Las anomalías esqueletales de clase II y clase III requieren tratamientos que asocian estética y función. El objetivo de esta investigación fue estudiar la relación entre tejidos blandos y duros faciales de pacientes con clase II y clase III facial, a nivel del tercio inferior facial. Se diseño un estudio descriptivo donde se incluyeron sujetos clase II con un ángulo SNB menor de 78 y clase III con un ángulo SNA menor de 80. Se analizó el ancho de tejidos blandos en relación a los putos Pg, punto A, punto B, y puntos cervicales de dientes incisivos maxilar y mandibular; también se analizaron los ángulos nasolabial e interincisivo; los estudios se realizaron en tomografía computadorizada cone beam y analizados en el software Simplant O&O (Materialise, Belgium). Los resultados demostraron semejanzas en las mediciones obtenidas en el ancho facial de tejidos blandos con diferencias menores a 1 mm en los puntos Pg, punto A, punto B y cervical incisivo maxilar; en relación al punto cervical del incisivo mandibular se observaron las mayores diferencias entre ambos grupos, cercanas a 5 mm de diferencia de tamaño en los tejidos; el ángulo nasolabial también presento diferencias entre ambos grupos, siendo en los sujetos clase III mas cerrado que en sujetos clase II (diferencia aproximada de 6). Se puede concluir que existen mínimas diferencias en el ancho de tejidos blandos en sujetos de clase II y clase III; otros parámetros pueden ser analizados para búsqueda de diferencias que influyan en planificaciones y estrategias terapéuticas para estos sujetos.

Analysis of the condyle, articular fossa and mandibular ramus in subjects with active condylar hyperplasia / Análisis del cóndilo, fosa articular y rama mandibular de sujetos con hiperplasia condilar activa

Facial asymmetry is relatively common, but it becomes a disease when condylar hyperplasia is involved. The purpose of this investigation was to describe and compare the morphological characteristics of hyperplastic condyles to their non-hyperplastic contralateral side. Fifteen subjects aged between 14 and 29 years with facial asymmetry and diagnosed with unilateral condylar hyperplasia were studied using cone-beam computerized tomography. Linear measurements were taken of the condylar morphology on the sagittal and coronal planes, establishing the size of the articular fossa, mandibular ramus, and other aspects. Sagittal condylar measurements showed significant differences (p=0.028) between the groups (hyperplastic side v/s non-hyperplastic side); ramus measurements showed significant differences (p=0.034) between the two sides. No significant differences were observed (p=0.155) in the relation of the mean lateral distance (coronal image) of hyperplastic and non-hyperplastic condyles. It can be concluded that there is an increase in the size of the hemimandible and TMJ on the hyperplastic side, although research with a greater number of patients is needed to establish a more precise trend.

La asimetría facial es relativamente común, transformándose en enfermedad cuando se asocia hiperplásia condilar. El objetivo de esta investigación fue describir y comparar las características morfológicas de los cóndilos hiperplásico con su contralateral no hiperplásico. Quince sujetos de entre 14 y 29 años de edad, con asimetría facial e hiperplasia condilar unliateral diagnosticada, fueron estudiados mediante tomografía computarizada Cone-Beam. Se determinaron mediciones lineales de la morfología condilar en vista coronal y sagital, estableciendo tamaños de la fosa articular, rama mandibular, entre otras. Las mediciones condilares sagitales mostraron diferencias significativas (p=0,028) entre los grupos (lado hiperplásico vs. lado no hiperplásico); las mediciones de longitud de rama mostraron diferencias significativas (p=0,034) entre ambos lados. No se observó diferencias significativas (p=0,155) en la relación de distancia medio lateral (imagen coronal) de cóndilos hiperplásico y no hiperplásicos. Concluimos que existe un aumento del tamaño hemimandibular y de la ATM del lado hiperplásico, aunque investigaciones con mayor número de pacientes son necesarios para establecer una tendencia mas exacta.

Seleccion de osteosintesis en la reconstruccion maxilar con injerto oseo de cresta Iliaca / Selection of osteosynthesis in maxillary reconstruction with iliac crest bone graft

La reconstrucci¢n ¢sea maxilar con injertos libres junto a la osteotom¡a Le Fort I ha sido desarrollada para dar respuesta a las necesidades cl¡nicas funcionales y est‚ticas de los pacientes, debido principalmente a la discrepancia antero-posterior de las maxilas atr¢ficas. Dentro de la t‚cnica, existe necesidad de osteos¡ntesis mediante fijaci¢n interna r¡gida (FIR) que puede ser desarrollada tanto con dispositivos met licos como con dispositivos reabsorbibles. El presente estudio eval£a el uso de ambos materiales de fijaci¢n, relatando las caracter¡sticas, comparaciones y situaciones cl¡nicas que podr¡an estar asociados a su elecci¢n.

The maxillary bone reconstruction with free flaps with LeFort I osteotomy has been developed to give answer to the functional and aesthetic clinical needs of patients, mainly due to the anteroposterior discrepancy of atrophic maxillae. Within the technique, there is need for osteosynthesis though rigid internal fixation (RIS) that can be developed as both metal devices and absorbable devices. This study evaluates the use of both fixing materials, relating the features, comparisons and clinical situations that might be associated with its choice.

Expansão cirúrgica de rebordo alveolar com instalação imediata de implantes / Edentulous ridge expansion with simultaneous implant placement

Introdução: após a perda dentária, o processo alveolar sofre atrofia gradativa, impossibilitando, em casos extremos, a reabilitação com implantes dentários. Objetivo: relatar um caso clínico de instalação de implantes imediatos em maxila edêntula atrófica, após aplicação da técnica de expansão cirúrgica do rebordo alveolar (ECR) na região anterior e levantamento do assoalho do seio maxilar (LS) nas regiões posteriores, em conjunto com enxerto ósseo autógeno removido do ramo ascendente da mandíbula. Conclusão: a ECR e o LS são alternativas viáveis, seguras e previsíveis para o aumento da espessura e altura do rebordo alveolar com finalidade reabilitadora.

Uso de guía de metil-metacrilato fabricados en biomodelo de poliuretano para el tratamiento tardío de fractura panfacial / The use of metil-metacrilate guide manufactured on biomodel of polyurethane for late treatment of panfacial fracture

El manejo de las secuelas faciales por fracturas no tratadas ha tenido un crecimiento importante debido al uso de los biomodelos. Estos permiten optimizar la cirugía, disminuir los tiempos quirúrgicos y mejorar los resultados. El presente articulo muestra un caso de secuela de fractura facial tratada con osteotomías con ayuda de guías quirúrgicos fabricados en base a un biomodelo operado; se presenta el resultado postoperatorio de 6 meses con una resolución adecuada.

The management of facial sequel by facial fractures non-treated nowadays presents an important expansion by the use of biomodels. This system can be used for reduce surgical time, optimize surgical protocol and improve outcomes. This paper presents a sequel case for facial fracture treated with bone osteotomy using surgical guide manufactured base on biomodels operated; is showing the postoperative 6 month follow-up with good results.