Alterations in masticatory cycle efficiency and bite force in individuals with periodontitis.

OBJECTIVES: The objective of this research was to evaluate the effect of periodontitis on masticatory cycle efficiency and maximum molar bite force. METHODS: Twenty-four individuals were divided into two groups: With periodontitis (Group I; mean age ± standard deviation (SD), 51.3 ± 2.8 years; n = 12) and without periodontitis (Group II; mean age ± SD, 48.9 ± 2.4 years; n = 12). Masticatory cycle efficiency was obtained from the value of the ensemble-averaged integrated linear envelope electromyographic signal of the masseter and temporalis muscles. Maximum bite force was recorded for the right and left molar regions. The data were tabulated and submitted to statistical analysis (P ≤ 0.05). RESULTS: There was a significant difference between the groups for the left masseter muscle when chewing raisins (P = 0.04), peanuts (P = 0.02), and biocapsules (P = 0.01). Multiple regression analysis demonstrated the influence of dental mobility on masticatory cycle efficiency for peanuts (P = 0.03) and biocapsules (P = 0.01). The maximum bite force for the left molar region was significantly different between the groups (P = 0.02). Dental mobility was a variable that had a greater effect on masticatory cycle efficiency. The periodontitis group had a reduced bite force. CONCLUSION: The present study findings indicate that the loss of periodontal supporting structures had a negative impact on masticatory cycle efficiency and molar bite force. This finding suggested that dental mobility should be considered when determining clinical treatments aimed at improving masticatory efficiency and bite force in individuals with the periodontal disease.

Evaluation of the electromyographic fatigue of the masseter and temporalis muscles in individuals with osteoporosis.

OBJECTIVES: The objective of this study was to evaluate the electromyographic fatigue of the masseter and temporalis muscles in individuals with and without osteoporosis. METHODS: Median frequency of the initial, mid, and final periods of the electromyographic signal in the 33 subjects with osteoporosis (OG) and 33 subjects without osteoporosis [control (CG)] was analyzed. RESULTS: OG showed a decrease in median frequency along the electromyographic signal, with a significant difference for the right masseter: initial vs. mid periods, initial vs. final periods; left masseter: initial vs. final periods; temporal (right and left): initial vs. mid periods, initial vs. final periods, and mid vs. final periods. Percentage comparison of median frequency between the initial and mid periods and between initial and final periods in the OG showed a significant difference in the masticatory muscles. DISCUSSION: The findings suggest that osteoporosis is associated with changes in the function of masticatory muscles, especially when measured by electromyographic fatigue.

Interactive audience response systems in oral and maxillofacial radiology undergraduate lectures.

OBJECTIVES: To evaluate the impact of audience response systems (ARS) on student participation (SP) during Oral and Maxillofacial Radiology (OMR) undergraduate lectures and on final examination scores (FES). Furthermore, an analysis of unanimity assessed the influence of ARS on students' responses. Students' perceptions were also assessed. METHODS: A controlled crossover study was designed. Four lectures covering topics of OMR were each taught with ARS and without ARS (i.e. hand-raising method). SP and FES were compared between ARS and HR groups. Unanimity of answers was analyzed for both groups. Questionnaires assessed students' impressions about ARS. RESULTS: Mean SP of ARS and HR groups were 97.6% and 47.3%, respectively, and this difference was statistically significant (P<.05). Mean FES for the ARS group (77%) was slightly higher than HR group (75.1%), however, not statistically significant. There was positive correlation between SP and FES. With ARS, only 5.7% of the questions were unanimous, whilst 51.4% were unanimous with HR method. Most students reported that the use of ARS had positive influence on their attention (92%), participation (96%), classmates' participation (82.7%), interest (74.7%), and learning (86.7%). For the five-point scale ratings of the relevance of ARS features, anonymity had an average 3.6, whilst other items received an average 4.6 or higher. CONCLUSIONS: ARS significantly increased participation in OMR lectures; however, an increase in FES could not be associated with ARS by itself. Not taking into consideration which method was used to answer questions posed during lectures, higher participation correlated with higher scores. ARS is well-accepted and students believe that these devices positively influence their performance. Among the recognized advantages of ARS, anonymity was considered the least relevant.

Neurovascular anatomical variations in the anterior palate observed on CBCT images.

OBJECTIVE: This study aimed to assess the presence of additional foramina and canals in the anterior palate region, through cone beam computed tomography (CBCT) images, describing their location, direction, and diameter. MATERIALS & METHODS: CBCT exams of 178 subjects displaying the anterior maxilla were included and the following parameters were registered: gender; age group; presence of additional foramina in the anterior palate (AFP) with at least 1 mm in diameter; location and diameter of AFP; and direction of bony canals associated with AFP. RESULTS: Twenty-eight patients (15.7%) presented AFP and in total 34 additional foramina were registered. No statistical differences between patients with or without AFP were found for gender or age. The average diameter of AFP was 1.4 mm (range from 1 to 1.9 mm). Their location was variable, with most of the cases occurring in the alveolar process near the incisors or canines (n = 27). In 18 cases, AFP was associated with bony canals with upward or oblique direction toward the anterior nasal cavity floor. In 14 cases, the canal presented as a direct extension of the canalis sinuosus, in an upward direction laterally to the nasal cavity aperture. In two cases, the canal was observed adjacent to the incisive and joined the nasopalatine canal superiorly. DISCUSSION: CBCT images have a crucial role in the recognition of anatomical variations by allowing detailed tridimensional evaluations. Additional foramina and canals in the anterior region of the upper jaw are relatively frequent. Practitioners should be aware and trained to identify these variations. CONCLUSIONS: Over 15% of the population studied had additional foramina in the anterior palate, between 1 mm and 1.9 mm wide, with variable locations. In most cases the canals associated with these foramina either presented as a direct extension of the canalis sinuosus, or coursed towards the nasal cavity floor.

Langerhans cell histiocytosis (Histiocytosis X) – in the mandible / Histiocitose das células de Langerhans (Histiocitose X): na mandíbula

This article reports a case of 65 year-old man consulted in a private radiology dental clinic for a panoramic radiography, where was indicated a radiolucent area, extending into the periapical region of the teeth 35 to 43 to the base of the mandible. Radiography diagnosis was difficult. The immunohistochemical examination showed immunoreactivity for the proteins CD 68, S-100 and CD 1a. Histopathological diagnosis was obtained for Langerhans cell granuloma (histiocytosis X). Langerhans cell histiocytosis is caused by the abnormal proliferation of histiocytes, previously called Histiocytosis X. It is a rare disease that preferentially affects children and young adults with a predilection for males and can affect different parts of the body.

Este artigo relata o caso de um homem de 65 anos que procurou uma clínica de radiologia dental particular para a realização de uma radiografia panorâmica. Foi detectada uma área radiolúcida na região apical dos dentes 35 a 43 que se estendia até a base da mandíbula. O exame imunoistoquimico da lesão mostrou proteínas reativas como a CD 68, S-100 e CD 1a. O diagnóstico do histopatológico foi de Granuloma de Células de Langerhans (Histiocitose X). A Histiocitose das células de Langerhans é causada pela proliferação anormal de histiócitos. É uma doença rara que preferencialmente acomete crianças e adultos jovens e tem predileção pelo sexo masculino, podendo afetar diferentes partes do corpo.

Avaliação do risco à osteopenia/osteoporose através do questionário avaliativo e sua associação com a análise morfológica do cortéx inferior da mandíbula realizadas em radiografias panorámicas / Risk assessment of osteopenia/osteoposis through the evaluation questionnaire and its association with the morphological analysis of the mandibular inferior cortex in panoramics radiographs

Objetivo: os autores apresentam uma proposta de questionário e conduta para referenciar pacientes com risco de osteoporose para avaliação médica...

Objective: The authors prepared a questionnaire for referring patients about the risk at osteoporosis...

A relação entre a sintomatologia de DTMS e a síndrome de eagle / The relationship between the symptoms of TMD and eagle syndrome

O objetivo deste estudo foi avaliar a presença de sintomas característicos da Síndrome de Eagle em pacientes com disfunção temporomandibular (DTM)...

The aim of this study was to assess the presence of characteristic symptoms of Eagle syndrome in patients with temporomandibular disorders (TMD)...

Programa para análise, processamento e armazenamento de laudos radiográficos odontológicos / Analysis software for processing and storage of dental radiographic reports

O presente trabalho descreve o desenvolvimento de um software com a finalidade de informatizar e facilitar a aquisição, armazenagem, acesso e consulta de dados de laudos radiográficos odontológicos. Para tal, foram utilizadas as linguagens MySQS. Desta forma foi possível criar um programa que possibilita a simulação dos dentes em uma imagem panorâmica (ex. girar; dimensionar e mover). O armazenamento de informações sobre os pacientes, radiografias utilizadas e possíveis alterações radiograficamente visíveis. Foram feitos até a presente data (29/06/2009) 2931 registros de interpretação radiográfica. Sua utilização propiciou um rico material para pesquisas de dados científicos e laudos radiográficos mais interativos com as imagens radiográficas.

Craniocervical posture and hyoid bone position in children with mild and moderate asthma and mouth breathing.

INTRODUCTION: The objective of the present study was to assess the craniocervical posture and the positioning of the hyoid bone in children with asthma who are mouth breathers compared to non-asthma controls. METHODS: The study was conducted on 56 children, 28 of them with mild (n=15) and moderate (n=13) asthma (14 girls aged 10.79+/-1.31 years and 14 boys aged 9.79+/-1.12 years), matched for sex, height, weight and age with 28 non-asthma children who are not mouth breathers. The sample size was calculated considering a confidence interval of 95% and a prevalence of 4% of asthma in Latin America. Eighteen variables were analyzed in two radiographs (latero-lateral teleradiography and lateral cervical spine radiography), both obtained with the head in a natural position. The independent t-test was used to compare means values and the chi-square test to compare percentage values (p<0.05). Intraclass correlation coefficient (ICC) was used to verify reliability. RESULTS: The Craniovertebral Angle (CVA) was found to be significantly smaller in asthma than in control children (106.38+/-7.66 vs. 111.21+/-7.40, p=0.02) and the frequency of asthma children with an absent or inverted hyoid triangle was found to be significantly higher compared to non-asthma children (36% vs. 7%, p=0.0001). The values of the inclination angles of the superior cervical spine in relation to the horizontal plane were significantly higher in moderate than in mild asthma children (CVT/Hor: 85.10+/-7.25 vs. 90.92+/-6.69, p=0.04 and C1/Hor: 80.93+/-5.56 vs. 85.00+/-4.20, p=0.04). CONCLUSIONS: These findings revealed that asthma children presented higher head extension and a higher frequency of changes in hyoid bone position compared to non-asthma children and that greater the asthma severity greater the extension of the upper cervical spine.

Morphodigital study of bone quality in the mandibular angle in patients with third molar impacted.

The aim of this study was to analyze if the presence of impacted third molars, and their positions in the mandibular angle, can change the bone quality in this area, considering the measure of the cortical thickness in this region as representative or not for mandible fracture risk. Software was used to analyze 50 digital images from panoramic radiographs of patients who had one or two impacted third molars in the mandible, and 30 digital images of patients with agenesis of the mandibular third molar. The thickness of the cortical region of the mandible was measured; it was possible to draw a parallel line to the posterior portion of the mandible and a parallel line to the body of this bone on each side of the image. At the intersection of these lines near the distal portion of the second molar, another line was set up to serve as reference in the cortical thickness measurement. It could be concluded that the cortical thickness of the mandibular angle in male patients without impacted third molars was greater than the thickness in patients with these teeth, and no difference in thickness was found for the female group.

Morphodigital Study of the Mandibular Trabecular Bone in Panoramic Radiographs / Estudio Morfodigital del Trabeculado Óseo Mandibular en Radiografías Panorámicas

The aim of this study was to correlate the morphodigital characteristics of the trabecular mandibular bone, in this way, it is possible to observe osteoporosis clue in patients of both sex, using panoramic radiograph for analysis. The results of this study showed statistical difference between men and women considering the bone trabecular measures (p<0.05), but it was not found statistical difference between the sides in each analyzed group (p>0.05). Male group presented a more strongly trabecular and complex bone than the female group, this finding is important index to osteoporotic risk, being possible to affirm that the male bone is less probable to suffer a osteoporotic fracture.

El objetivo de este estudio fue correlacionar las características morfodigitales del trabeculado óseo mandibular para de esta manera, verificar indicios de señales de osteoporosis, utilizando para esto, radiografías panorámicas de pacientes de ambos sexos. Los resultados del estudio mostraron diferencias entre los grupos masculino y femenino, en la cuantificación de hueso trabecular mandibular (p<0,05), pero no se encontraron diferencias enter los lados derecho e izquierdo en cada grupo analizado (p>0,05). El grupo masculino presentó un padrón óseo trabecular más compleo y fuerte que el grupo femenino. Este hallazgo puede ser un importante indicador en cuanto a los riesgos de osteoporosis, por ejemplo, siendo posible afirmar que los huesos de los individuos del grupo masculino están menos sujetos a riesgo de fractura por osteoporosis.

A Singular Method to Compare Dental Radiographic Films Used to Study Maxillofacial Structures / Un Singular Método Comparativo de Radiografías Dentales Usadas en Estudios de Estructuras Maxilofaciales

The aim of this article is to present a singular and practical method to compare roentgenograms, concerning optical density and contrast. This method is specifically indicated for research related to stepwedge penetrometer and photodensitometer.

El objetivo de este artículo es presentar un método singular y práctico para comparar roentgenogramas, referentes a la densidad óptica y al contraste. Este método se indica específicamente para la investigación con el penetrómetro stepwedge y el fotodensitómetro.

Densidad osea bilateral comparativa del ángulo de la mandíbula / Comparative bilateral bone density of the mandible angle

The aim of this study was to assess a bilateral comparison of the mandible density in both sex young patients with computer densitometry. Fifty panoramic radiographs were obtained from young patients with ages between 18 and 23 years old (group A = 25 female and group B = 25 male) standardized, using the same X-Ray equipment (Siemens, lOKvp, 7mA), scanned with a 282.110 pixels resolution, and transferred later to a computer and using the SIDEXIS (Sirona, USA) program to analyze the bone densitometry performance. Bilateral sites were standardized with the objective to measure the bone density. Obtained data were registered and submitted to statistical analysis. The following means and standard deviations were obtained, in pixels, for the right and the left side, respectively: group A= 154.36 +/- 36.90 e 186.12 +/- 31.41, group B= 162.07 +/- 34.94 and 180.15 +/- 30.96. These values show statistical difference between different sides and groups (p<0.05), with a higher bone density on the left side in both groups, especially in group A.

El objetivo de este estudio fue realizar una comparación bilateral de la densidad de mandíbula en pacientes jóvenes de ambos sexos con computadora densitométrica ósea. Fueron obtenidas 50 radiografías panorámicas de pacientes jóvenes entre 18 y 23 años de edad (Grupo A = 25 femenino y el grupo B = 25 masculino), utilizando el mismo equipo de radiografía (Siemens, 1 OKvp, 7mA). Se escaneó con una resolución de 282,110 pixels, transfiriéndose luego a un computador para el estudio por medio del programa SIDEXIS (Sirona, USA) para analizar el desempeño densitométrico de hueso. Los sitios bilaterales fueron estandarizados con el objetivo de medir la densidad de hueso. Los datos obtenidos fueron registrados y sometidos a análisis estadístico. Las medias y los desvíos padrón fueron obtenidos en pixels, para el lado derecho y el lado izquierdo, respectivamente: Grupo A = 154,36 +/-36,90 y 186,12 +/- 31,41, grupo B = 162,07 +/- 34,94 y 180,15 +/- 30,96. Estos valores muestran la diferencia estadística entre lados y grupos diferentes (p<0,05), con una densidad más alta de hueso en el lado izquierdo en ambos grupos, especialmente en grupo A.

Análisis del patrón óseo trabecular de mandíbulas maceradas en radiografías panorámicas digitales / Analysis of the trabecular bone pattern of dry human mandibles in digital panoramic radiographies

Nuestro propósito fue estudiar la sensibilidad de la metodología de esqueletonizacion en las alteraciones del patrón óseo trabecular, en radiografías panorámicas digitales. Con el fin de poder utilizar esta metodología a futuro para el análisis y la observación de los cambios de densidad ósea en la estructura trabecular, en pacientes con osteoporosis y sanos. El material examinado consistió en cinco mandíbulas adultas, maceradas. Los 4 sitios de interés de cada mandíbula fueron escogidos en cuerpo mandibular, debajo de los alvéolos dentarios: Sitio 1. Oral y anterior al foramen mentoniano derecho. Sitio 2. Oral y posterior al foramen mentoniano derecho. Sitio 3. Oral y anterior al foramen mentoniano izquierdo. Sitio 4. Oral y posterior al foramen mentoniano izquierdo. Se realizó la toma de radiografías panorámicas digitales. Posterior a la primera toma radiográfica, se recortaron las áreas delimitadas removiendo las tablas vestibulares, Se fracturó intencionalmente el trabeculado óseo y luego se reubicaron las tablas vestibulares y se realizó una segunda toma radiográfica, con el uso de un soporte confeccionado para el posicionamiento de las mandíbulas, manteniendo las líneas guía fijas,para cada especimen: Plano mediano, Línea canina y Plano de Frankfurt. Los sitios de interés fueron trabajados en software, siguiendo el método empleado por Watanabe (2003), las imágenes resultantes, que muestran los esqueletos de las trabéculas óseas fueron analizadas utilizando las siguientes herramientas: Histograma, Análisis de partículas, Dimensión fractal, Cantidad de Uniones o encuentro triple de trabéculas y Porcentaje de trabéculas por área. En el análisis estadístico según los datos obtenidos de las diferentes regiones, antes y después de la remoción/inserción, no se encontró una diferencia estadísticamente significativa. Las trabéculas vistas en la radiografía panorámica son formadas principalmente por inserciones en las corticales. El método de retirar la tabla óse...

Efeito de baixas doses de radiaçäo X em feridas suturadas e näo suturadas: estudo experimental em ratos / Effect of low doses of X-irradiation in sutured and nonsutured wounds: experimental study in rats

O presente trabalho avaliou o efeito de baixas doses de radiaçäo X no processo de reparaçäo tecidual em feridas suturadas e näo suturadas em ratos. Para tanto, foi produzida nos animais uma ferida medindo 20 x 5 mm, sendo suturadas ou näo, dividindo-se os animais em 4 grupos: controle sem sutura, irradiado sem sutura, controle com sutura e irradiado com sutura. Os animais irradiados foram, no momento da irradiaçäo, protegidos com um avental de chumbo de 2 mm de espessura com uma abertura, a qual permitia que fosse exposta somente a ferida cirúrgica. Cada animal sofreu 18 segundos de irradiaçäo, totalizando 7,4 rad. O processo de reparaçäo tecidual foi avaliado pela coloraçäo por hematoxilina-eosina, verificando-se a morfologia do tecido de granulaçäo e a impregnaçäo argêntica para observaçäo da síntese de colágeno, através da microscopia de polarizaçäo. Os resultados mostraram que a radiaçäo, apesar de ter causado atraso, näo impediu a reparaçäo tecidual, sendo que o grupo que sofreu irradiaçäo e näo foi suturado mostrou maior retardo, quando comparado aos outros grupos

Alteraçäo do plano de orientaçäo de Frankfurt em telerradiografias frontais / Alteration of the Frankfort orientation plane in posteroanterior cephalometric radiography

Os autores estudaram possíveis influências em mensuraçöes angulares e lineares verticais do Plano Horizontal de Frankfurt (PHF) quando utilizado como plano de orientaçäo em telerradiografias póstero-anteriores. Foram utilizadas 90 telerradiografias póstero-anteriores, obtidas de 30 pacientes em 3 posiçöes: PHF paralelo ao Plano Horizontal, PHF formando ângulos de mais 5 graus e PHF formando ângulos de menos 5 graus em relaçäo horizontal. Os resultados mostraram que 5 dentre as 6 medidas angulares e 3 dentre as 11 medidas lineares verticais estudadas näo mostraram diferença estatisticamente significante. Os autores concluíram que, em casos de inclinaçäo do plano de orientaçäo em telerradiografias póstero-anteriores, as medidas angulares säo mais confiáveis do que as medidas lineares verticais. As medidas lineares verticais mostraram-se altamente sensíveis às inclinaçöes quando os planos coronais näo säo muito próximos; as angulares só mostram perda de confiabilidade quando os pontos cefalométricos estäo em planos coronais bem distantes

Polidrâmnio: aspectos clínicos / Polyhydranios: clinical aspects

Um total de 50 gestantes portadoras de polidrâmnio foi estudado e analisado quando a dados de identificaçäo, antecedentes, patologias clínicas associadas, meios de diagnóstico, conduta e resultados perinatais. A incidência de polidramnia foi de 0,17%. Verificou-se maior incidência desta entidade em multíparas e naquelas com idade superior a 30 anos. O diabetes mellitus, a gestaçäo múltipla e as malformaçöes congênitas estiveram presentes respectivamente em 14%, 32% e 18% dos casos. Foi elevada a mortalidade perinatal (36,3%), bem como a prematuridade (54%)