OncoTherad® (MRB-CFI-1) Nanoimmunotherapy: A Promising Strategy to Treat Bacillus Calmette-Guérin-Unresponsive Non-Muscle-Invasive Bladder Cancer: Crosstalk among T-Cell CX3CR1, Immune Checkpoints, and the Toll-Like Receptor 4 Signaling Pathway.

This study assessed the safety and efficacy of OncoTherad® (MRB-CFI-1) nanoimmunotherapy for non-muscle invasive bladder cancer (NMIBC) patients unresponsive to Bacillus Calmette-Guérin (BCG) and explored its mechanisms of action in a bladder cancer microenvironment. A single-arm phase I/II study was conducted with 44 patients with NMIBC who were unresponsive to BCG treatment. Primary outcomes were pathological complete response (pCR) and relapse-free survival (RFS). Secondary outcomes comprised response duration and therapy safety. Patients' mean age was 65 years; 59.1% of them were refractory, 31.8% relapsed, and 9.1% were intolerant to BCG. Moreover, the pCR rate after 24 months reached 72.7% (95% CI), whereas the mean RFS reached 21.4 months. Mean response duration in the pCR group was 14.3 months. No patient developed muscle-invasive or metastatic disease during treatment. Treatment-related adverse events occurred in 77.3% of patients, mostly grade 1-2 events. OncoTherad® activated the innate immune system through toll-like receptor 4, leading to increased interferon signaling. This activation played a crucial role in activating CX3CR1+ CD8 T cells, decreasing immune checkpoint molecules, and reversing immunosuppression in the bladder microenvironment. OncoTherad® has proved to be a safe and effective therapeutic option for patients with BCG-unresponsive NMIBC, besides showing likely advantages in tumor relapse prevention processes.

Prospective study of the aesthetic effect of botulinum toxin a when injected into the muscles of facial expression

Botulinum neurotoxin A (BoNT-A) causes an anticholinergic effect on neuronal fibers, which control muscle contraction and autonomic disorders. Thus, it has been widely used in facial aesthetics, decreasing the action of motor muscles and consequent wrinkles. This preliminary study evaluated the effect of BoNT-A in 77 patients, the treatment satisfaction index was defined in percentage (from 0% to 100%). The evaluation was carried out on 15th, 30th, 60th, 90th, and 180th days after BoNT. The data were analyzed using the Friedman, Student t, Mann-Whitney test with t (alpha=0.05). The results showed that at 15th and 30th days the scores were similar in all muscles with high level of satisfaction and until 90th days the scores decreased significantly for Corrugator supercilii 79.38%, Occipitofrontalis 71.46%, Orbicularis oculi 70.43%; but the satisfaction was good. At 180 days, there was a drop in effectiveness in all treated muscles since the scores decreased significantly, showing low satisfaction by the participants. This study demonstrated that the BoNT-A had attested satisfaction effect by participants for up to 90th days, but at 180th days the satisfaction was low. In the comparative analyzes between women under 40 and over 40 years of age, there was no significant differences.

Is low dose of botulinum toxin effective in controlling chronic pain in sleep bruxism, awake bruxism, and temporomandibular disorder?

OBJECTIVE: To evaluate the effects of low doses of botulinum toxin type A (BoNT-A) to control pain in patients with sleep bruxism (SB), awake bruxism (AB), and temporomandibular disorder (TMD) during 180 days. METHODS: Overall sample of thirty-five patients with chronic pain related to TMD, SB, and AB received a single dose of 20 U of BoNT-A in masseter and temporalis muscles. The pain was assessed with a visual analog scale (VAS) before and after 15, 30, 60, 90, and 180 days of the application. RESULTS: The three clinical conditions experienced decrease in pain after 15 days of treatment (p < 0.0001); the maximum pain relief persisted for up to 90 days after BoNT-A application in patients with SB and AB and 15 days for patients with TMD. CONCLUSION: A low dose of BoNT-A may be effective for controlling chronic pain related to SB and AB, but TMD pain reduction was short-lived.

How many implants are needed for mandibular full-arch rehabilitation?

Aim: To analyze the stress distribution at the peri-implant bone tissue of mandible in full-arch implant-supported rehabilitation using a different number of implants as support. Methods: Three-dimensional finite element models of full-arch prosthesis with 3, 4 and 5 implants and those respective mandibular bone, screws and structure were built. ANSYS Workbench software was used to analyze the maximum and minimum principal stresses (quantitative analysis) and modified von Mises stress (qualitative analysis) in peri-implant bone tissue after vertical and oblique forces (100N) applied to the structure at the cantilever site (region of the first molars). Results: The peak of tensile stress values were at the bone tissue around to the distal implant in all models. The model with 3 implants presented the maximum principal stress, in the surrounding bone tissue, higher (~14%) than the other models. The difference of maximum principal stress for model with 4 and 5 implants was not relevant (~1%). The first medial implant of the model with 5 implants presented the lower (17%) stress values in bone than model with 3 implants. It was also not different from model with 4 implants. Conclusion: Three regular implants might present a slight higher chance of failure than rehabilitations with four or five implants. The use of four implants showed to be an adequate alternative to the use of classical five implants

Resorptive potential of impacted mandibular third molars: 3D simulation by finite element analysis.

OBJECTIVES: Previous studies have suggested a relationship between resorption in second molars and pressure from the eruptive force of the third molar. The aim of this study was to simulate functional forces in a mandible model by means of finite element analysis and then assess the biomechanical response produced by impacted third molars on the roots of the second molar. MATERIALS AND METHODS: A cone beam computed tomography scan presenting an impacted mandibular third molar was segmented (Mimics V17 software). The modeling process was performed using the reverse engineering technique provided by the Rhinoceros 3D 5.0 software. The third molar position was changed in order to produce different inclinations of the impacted tooth. Bite forces were simulated to evaluate total deformation, the equivalent von Mises stress, minimum principal stress on hard tissue, and equivalent elastic strain on soft tissue. RESULTS: Areas of high energy dissipation and compression stress were detected in the second molar root, independently of the inclination of the impacted third molar. In general, the horizontal position was the situation in which major stress and the amount of deformation occurred in the second and third molar regions. CONCLUSION: Impacted third molars in close proximity with the adjacent tooth can generate areas of compression concentrated at the site of contact, which suggests an involvement of mechanical factors in the triggering of resorption lesions. CLINICAL RELEVANCE: The results of these computational experiments contribute to the understanding of the triggering and progression of resorptive lesions in the adjacent second molar.

The effect of a hydroxyapatite impregnated PCL membrane in rat subcritical calvarial bone defects.

OBJECTIVE: The present study evaluated the effect of polymeric-nanofibers membranes impregnated with microparticulate hydroxyapatite (HA) in the subcritical calvarial bone defects (SCBD) healing. DESIGN: PCL membranes with and without HA were obtained by electrospinning. SCBD were perforated (3.3mm) in left and right sides of 36 rat calvarias. The right-side SBCD of 18 animals was filled with HA mixed with blood clot and blood clot at the contralateral side. The remaining animals received PCL+HA membrane at the right-side SCBD and PCL membrane at the contralateral side. Animals were killed after 30, 60 and 90days after surgery. Bone defect volume (in mm3) was measured by tomography (CBCT). Qualitative histological analysis and SBCD area (in mm2) were measured. Quantitative data were submitted to Kruskal-Wallis/Dunn tests. RESULTS: Reduction of SBCD volume was observed in all treatments but PCL. Association with HA significantly improved bone healing induced by PCL and blood clot. PCL+HA induced the lowest SBCD volume at 60 and 90days. Complete bone healing was not observed even at 90days in SCBD treated with blood clot. In every period, more bone formation was observed for SCBD treated with membranes. CONCLUSIONS: We concluded that both PCL membrane and HA were able to improve bone healing.

Twist removal of healed vs. nonhealed implants-a mechanical and histological study in mini pigs.

PURPOSE: The objective of this study was to evaluate the effect of removal torque (reverse torque) of titanium implants in peri-implant bone. METHODS: The P1-M1 teeth were extracted bilaterally of 6 mini pigs (BR-1). Each animal received 6 titanium implants, three for each side of mandible. On the right side of mandible, 3 implants reminded 9 months (9M) under masticatory activity and on the left side, other 3 implants were placed and immediately removed (IR). All 36 implants were removed by removal torque, and the recorded values were statistically analyzed. Animals were euthanized right after the removal torque and recording. Each third (cervical, medium, and apical) of peri-implant bone was extracted and analyzed histological and immunohistochemically. Student's t test was used to determine statistical differences in the values between the 9M and IR samples. Data were presented as means with standard deviations. The level of significance was set at 5% (P < 0.05). RESULTS: Removal torque was higher in 9M experimental situation than in IR. Histological characteristics of mature bone were presented in the 9M experimental condition, and immature bone characteristics were presented in the IR experimental condition. Removal torque caused small fractures and rounding in the bone grooving. Immunohistochemical analysis reinforced the histological results; Student's t test provided statistically significant differences to osteocalcin expression in 9M samples and no statistically significant differences expression to collagen I in both experimental conditions (P < 0.05). CONCLUSIONS: Removal torque caused microscopical fractures and smoothing in the peri-implant bone grooves, but it does not compromise the bone healing.

Rotation axis of the maxillary molar and maximum tooth movement according to force direction

Aim: To evaluate the correlation between the maxillary molar rotation center and the direction of the maximum tooth movement according to the force direction using three-dimensional finite element analysis (3D-FEA) Methods: Computed tomography of a human tooth was used to build a finite element model, which comprised the cancellous and cortical bones, the periodontal ligament and the tooth. After applying lateral and posterior boundary conditions, a 1 N force was applied to the mesial and lingual faces of the maxillary molar to simulate buccal and distal tipping forces on the tooth. Results: The initial displacement of the maxillary first molar was greater for distal tipping than for buccal tipping. The rotation axis for distal tipping in this simulation was located on the furcation of the first molar. For buccal tipping this axis was on the cervical and middle third of the buccal roots of the maxillary first molar. Conclusions: The applied movement interferes in molars Cres location. Higher molar tipping is expected when distal movement is applied rather than buccal movement thanks to the close distance between Cres and location of the force applied to this movement.

Correlation of stress and muscle activity of patients with different degrees of temporomandibular disorder.

[Purpose] Temporomandibular disorder is one of the many different adverse health conditions that can be triggered by stress. Therefore, a biopsychosocial model has been proposed to characterize the multifactorial nature of temporomandibular disorder. The aim of the present study was investigate the correlation of salivary cortisol levels with the activities of the masseter and anterior temporal muscles of patients with different degrees of temporomandibular disorder. [Subjects and Methods] Forty-nine women between 18 and 40 years of age with a diagnosis of myogenous temporomandibular disorder based on the Research Diagnostic Criteria for temporomandibular disorders were evaluated using the Fonseca Index to determine the degree of the disorder. Salivary cortisol levels were determined and surface electromyography was used to evaluate electrical activity in the masticatory muscles. [Results] Positive correlations were found among the degree of temporomandibular disorder, electromyographic activity and salivary cortisol: as women with more severe temporomandibular disorder had greater electrical activity in the muscles analyzed, especially the anterior temporal muscle, and higher levels of cortisol. [Conclusion] Muscle activity was greater among individuals with severe temporomandibular disorder and positive correlations were found among electromyographic activity, salivary cortisol and the degree of temporomandibular disorder severity.

Finite-element analysis of 3 situations of trauma in the human edentulous mandible.

PURPOSE: Maxillofacial trauma resulting from falls in elderly patients is a major social and health care concern. Most of these traumatic events involve mandibular fractures. The aim of this study was to analyze stress distributions from traumatic loads applied on the symphyseal, parasymphyseal, and mandibular body regions in the elderly edentulous mandible using finite-element analysis (FEA). MATERIALS AND METHODS: Computerized tomographic analysis of an edentulous macerated human mandible of a patient approximately 65 years old was performed. The bone structure was converted into a 3-dimensional stereolithographic model, which was used to construct the computer-aided design (CAD) geometry for FEA. The mechanical properties of cortical and cancellous bone were characterized as isotropic and elastic structures, respectively, in the CAD model. The condyles were constrained to prevent free movement in the x-, y-, and z-axes during simulation. This enabled the simulation to include the presence of masticatory muscles during trauma. Three different simulations were performed. Loads of 700 N were applied perpendicular to the surface of the cortical bone in the symphyseal, parasymphyseal, and mandibular body regions. The simulation results were evaluated according to equivalent von Mises stress distributions. RESULTS: Traumatic load at the symphyseal region generated low stress levels in the mental region and high stress levels in the mandibular neck. Traumatic load at the parasymphyseal region concentrated the resulting stress close to the mental foramen. Traumatic load in the mandibular body generated extensive stress in the mandibular body, angle, and ramus. CONCLUSIONS: FEA enabled precise mapping of the stress distribution in a human elderly edentulous mandible (neck and mandibular angle) in response to 3 different traumatic load conditions. This knowledge can help guide emergency responders as they evaluate patients after a traumatic event.

Efficiency of occlusal splints on police officers with TMD

Aim: To evaluate of the effect of two different occlusal splints on police officers with TMD. Methods: Thirty police officers were selected based on Research Diagnostic Criteria for TMD and on clinical exams. Volunteers (ten per group) were distributed according to occlusal splints: group A - Control, group B - Michigan Occlusal Splint (MOS), and group C - Planas Appliance (PA). Experimental groups were analyzed using a visual analog pain scale (VAPS), subject to a clinical evaluation of temporomandibular joint. Bilateral surface electromyographic activities of anterior and posterior temporal, masseter and suprahyoid muscles were analyzed at rest and during clenching, before and after four weeks using the occlusal splints. Results: The left and right temporal and masseter muscles sensitivity decreased after using both splints. Pain symptoms increased for group A (Control) and decreased for group C. Conclusions: Planas Appliance was more efficient on pain reduction than the Michigan Occlusal Splint.

Photoelastic and finite element analyses of occlusal loads in mandibular body.

This study proposed to evaluate the mandibular biomechanics in the posterior dentition based on experimental and computational analyses. The analyses were performed on a model of human mandible, which was modeled by epoxy resin for photoelastic analysis and by computer-aided design for finite element analysis. To standardize the evaluation, specific areas were determined at the lateral surface of mandibular body. The photoelastic analysis was configured through a vertical load on the first upper molar and fixed support at the ramus of mandible. The same configuration was used in the computer simulation. Force magnitudes of 50, 100, 150, and 200 N were applied to evaluate the bone stress. The stress results presented similar distribution in both analyses, with the more intense stress being at retromolar area and oblique line and alveolar process at molar level. This study presented the similarity of results in the experimental and computational analyses and, thus, showed the high importance of morphology biomechanical characterization at posterior dentition.

Bone Substitutes used in Dentistry / Sustitutos Óseos Utilizados en Odontología

Repair of bone defects resulting from trauma, tumor resections and infections is a medical and dental problem that needs a practical and low cost solution. To facilitate the repair several grafts or bone substitutes may be applied inside the defects. Biomaterials allow treatment, increase or replacement of any tissue, organ or function of the body. The aim of this study was to approach the advantages, disadvantages and main applications of bone substitutes used in reconstruction searched in dental practice. The manuscripts used in this literature review were searched in Medline (PubMed) and Scopus databases and based on manuscripts published from 1991 to 2012. After reading the titles and abstracts of the manuscripts, studies were selected because of their correlations with the aim of the current study. Bone tissue engineering has emerged as a new area of regenerative medicine and biomaterials and has an essential function concerning osteoconductive scaffold, osteogenic growth factors, and osteogenic cells. Based on literature available, a combination of advantageous properties of natural resorbable polymers and bioactive material in nanoscale appears to be more relevant for use in bone defects.

La reparación de defectos óseos que resultan de traumas, resección de tumores e infecciones son un problema médico y dental que necesitan una solución práctica y de bajo costo. Para facilitar la reparación, diversos injertos o sustitutos óseos pueden ser aplicados en el interior de los defectos. Los biomateriales permiten tratar, aumentar o sustituir algún tejido, órgano o función del cuerpo. El objetivo de este estudio fue acercarse a las ventajas, desventajas y principales aplicaciones de los sustitutos óseos utilizados para la reconstrucción en la práctica dental. Los manuscritos utilizados en esta revisión sistemática de la literatura se realizaron mediante la búsquedas en Medline (PubMed) y bases de datos Scopus, basada en manuscritos aparecidas entre 1991 y 2012. Después de leer los títulos y resúmenes de los manuscritos, los estudios fueron seleccionados debido a su correlación con el objetivo del presente estudio. Ingeniería de tejido óseo se ha convertido en una nueva área de la medicina regenerativa y biomateriales y tiene una función esencial en relación osteoconductivo andamio, factores de crecimiento osteogénicos, y las células osteogénicas. Basado en la literatura disponible, una combinación de propiedades ventajosas de polímeros reabsorbibles naturales y el material bioactivo en nanoescala que parece ser más relevante para su uso en defectos óseos.

The application of finite element analysis in the skull biomechanics and dentistry.

Empirical concepts describe the direction of the masticatory stress dissipation in the skull. The scientific evidence of the trajectories and the magnitude of stress dissipation can help in the diagnosis of the masticatory alterations and the planning of oral rehabilitation in the different areas of Dentistry. The Finite Element Analysis (FEA) is a tool that may reproduce complex structures with irregular geometries of natural and artificial tissues of the human body because it uses mathematical functions that enable the understanding of the craniofacial biomechanics. The aim of this study was to review the literature on the advantages and limitations of FEA in the skull biomechanics and Dentistry study. The keywords of the selected original research articles were: Finite element analysis, biomechanics, skull, Dentistry, teeth, and implant. The literature review was performed in the databases, PUBMED, MEDLINE and SCOPUS. The selected books and articles were between the years 1928 and 2010. The FEA is an assessment tool whose application in different areas of the Dentistry has gradually increased over the past 10 years, but its application in the analysis of the skull biomechanics is scarce. The main advantages of the FEA are the realistic mode of approach and the possibility of results being based on analysis of only one model. On the other hand, the main limitation of the FEA studies is the lack of anatomical details in the modeling phase of the craniofacial structures and the lack of information about the material properties.

Relations between the mandibular canal and I, II and III Angle classes in panoramic radiographs / Relaciones entre el canal mandibular y clases I, II y III de Angle en radiografías panorámicas

To prevent injury to the inferior alveolar nerve during dental procedures, knowledge of its anatomical location and course of the mandibular canal is imperative. The aim of this study was evaluate the location on panoramic radiographs of the mandibular canal in relation to the apices of the permanent mandibular molars and base mandible, and relate the type of mandibular canal with Angle classes I, II and III. We evaluated 748 panoramic radiographs distributed according to sex and occlusal class (Angle I, II and III) of fully dentate individuals, 18­51 age group. The radiographs were divided according to Angle classes based on cephalometric tracing, clinical data from the medical records of each individual and the analysis of of the maxillar and mandibular dental arches models. The same individuals had the mandibular canal bilaterally assessed, and classified according to their location relative to the root apices of the mandibular molars and mandible base. Measurements of the distance from the mandibular canal to the apices of the teeth and mandible base were made on the Software ImageLab2000®. The intra-observer reproducibility of measurements on radiographs was assessed using the coefficient of variation (p<0.0001). Data were submitted to Kruskal-Wallis test, on software BioEstat 5.0. There were statistically significant differences (Kruskal-Wallis test, p <0.0001) between the occlusal classes, with the type of mandibular canal. A larger number of canals types 2 and 3 in class III individuals than in others. In conclusion, the location of the mandibular canal presents morphological changes in relation to the apices of the permanent molars, and the mandibular base according to the Angle classes I, II and III.

Para evitar lesiones del nervio alveolar inferior durante los procedimientos odontológicos, el conocimiento de la localización anatómica y curso del canal mandibular (CM) es imprescindible. El objetivo fue evaluar la localización del CM sobre radiografías panorámicas en relación con los ápices de los molares mandibulares permanentes y la base mandibular, relacionando el tipo de CM con las clases I, II y III de Angle. Se evaluaron 748 radiografías panorámicas distribuidas según sexo y clase oclusal (I, II y III de Angle) en individuos totalmente dentados (edad entre 18-51 años). Las radiografías fueron divididas de acuerdo a las clases de Angle según su trazado cefalométrico, datos clínicos de los registros médicos de cada individuo y el análisis de modelos de sus arcos dentarios mandibulares y maxilares. En los individuos se evaluó el CM bilateralmente y se clasificó de acuerdo a su ubicación en relación con los ápices radiculares de los molares mandibulares y base mandibular. Las mediciones de distancia desde el CM a los ápices radiculares y base mandibular se hicieron con el programa ImageLab2000®. Se evaluó la reproducibilidad intra-observador de las mediciones en las radiografías usando el coeficiente de variación (p<0,0001). Los datos fueron sometidos a la prueba de Kruskal ­Wallis con el programa BioEstat 5.0. Se observaron diferencias estadísticamente significativas (prueba de Kruskal-Wallis, p<0,0001) entre las clases oclusales y el tipo de CM. Hubo mayor número de canales tipos 2 y 3 en los individuos clase III. La ubicación del canal mandibular presenta cambios morfológicos en relación con los ápices de molares permanentes y la base mandibular de acuerdo a las clases I, II y III de Angle.

Biomechanics of the human canine pillar based on its geometry using finite element analysis / Biomecánica del pilar canino en el cráneo humano basada en la geometría utilizando análisis de elementos finitos

This study evaluated the stress distribution based on the canine pillar geometry in human skull, using a finite element analysis. Computed tomography of human skull was used to build a finite element model, which was composed by all bony structures of canine pillar: canine eminence, canine fossa, frontal process of maxilla, glabellum and superciliary arch. A support on the bite contact of maxillary canine tooth and a resultant force of the masticatory muscles was applied in the simulation. Equivalent Von-mises and maximum principal stresses were analyzed along the structures that compose the canine pillar geometry. Von-mises stress presented high stress concentrated at the canine fossa and frontal process of maxilla. Maximum principal stress showed compression areas at the canine fossa and part of frontal process and tensile stress at canine eminence and part of the frontal process. In conclusion, the different stress areas means different force concentrations transmitted along the canine pillar geometry during a peak canine bite.

Este estudio evaluó la distribución de la tensión sobre la geometría del pilar canino en el cráneo humano, utilizando análisis de elementos finitos. Se usó la tomografía computarizada de cráneo humano para construir un modelo de elementos finitos compuesto por todas las estructuras óseas del pilar canino: eminencia canina, fosa canina, proceso frontal del maxilar, glabela y arco superciliar. Se aplicó en la simulación un soporte ubicado sobre el contacto de mordida del diente canino maxilar y una fuerza resultante de los músculos de la masticación. Tensiones Equivalentes de Von-Mises y tensiones principales máximas fueron analizadas a lo largo de las estructuras que componen la geometría de pilar canino. La tensión de Von-Mises fue alta y concentrada en la fosa canina y proceso frontal del maxilar. La tensión principal máxima mostró áreas de compresión en la fosa canina y parte del proceso frontal y la tensión de tracción en la eminencia canina y parte del proceso frontal. Las diferentes áreas de tensión significan diferentes concentraciones de tensiones transmitida a lo largo de la geometría del pilar canino durante una mordedura canina máxima.

Stress distribution in human zygomatic pillar using three-dimensional finite element analysis / Distribución de la tensión en el pilar cigomático humano usando análisis de elementos finitos tridimensional

This paper aimed to analyze stress distribution in human zygomatic pillar during masseter muscle contraction using three-dimensional finite element analysis. A three-dimensional model and hemi facial skull were produced based on CT-scan data. An adult male skull with structural anatomy integrity was used as model. Muscles forces were applied at origin of elevator muscles and supports was applied at the occlusal surfaces at first and second molars to simulate a masticatory load and stimulate the zygomatic pillar. Supports were applied to the occlusal contacts. Symmetry conditions were placed at the mid-sagittal plane. For the top and back cutting plane, constraints were used. Equivalent Von-Mises Stress and Maximum Principal Stress analysis were performed from the stress fields along the zygomatic pillar. It was represented by stress concentration at the alveolar process, zygomatic bone, frontal and temporal process of zygomatic bone and superciliary arch. Stress line indicates distribution of stress from maxilla toward the frontal and temporal bone. The stresses occurred due to resultant occlusal forces is mainly supported by the zygomatic bone, non-uniformly distributed and predominantly through the zygomatic pillar. This study contributed to better understanding of stress distribution in zygomatic pillar to understand the influence of chewing on zygomatic pillar morphology and also be useful for clinical practice.

El objetivo de este artículo fue analizar la distribución de la tensión en el pilar cigomático humano durante la contracción del músculo masetero utilizando análisis de elementos finitos tridimensionales. Un modelo de tres dimensiones de dientes del hemicráneo facial fueron producidos sobre la base de datos de CT-scan. Se utilizó como modelo un cráneo adulto de sexo masculino con la integridad de la anatomía estructural. Fuerzas musculares se aplicaron en el origen de los ascensores de los músculos de la mandíbula y soportes se aplicaron a la superficie oclusal del primer y segundo molar para simular una carga masticatoria y estimular el pilar cigomático. Condiciones de simetría se colocaron en el plano mediano. Se utilizaron restricciones en los planos superior y posterior. El análisis de las tensiones equivalentes von-Mises y máximo director se realizó a través del campo de esfuerzos a lo largo del pilar cigomático. Fue representada la concentración de esfuerzos en el proceso alveolar, hueso cigomático, proceso frontal y temporal del hueso cigomático y el arco superciliar. La línea de tensión indica la distribución de la tensión del maxilar hacia el hueso frontal y temporal. Las tensiones se produjeron debido a las fuerzas oclusales resultantes, que se apoyan principalmente por el hueso cigomático, distribuidas de manera no uniforme y sobre todo a través del pilar cigomático. Este estudio ha contribuido a una mejor comprensión de la distribución de la tensión en el pilar cigomático para entender la influencia de la masticación sobre la morfología de este pilar y ser de utilidad en la práctica clínica.

Comparison of distance and symmetry in the mental foramen obtained in situ and in radiographic images of Brazilians / Comparação da distância e simetria dos forames mentonianos obtidos em loco e em imagens radiográficas na população brasileira

The precise location of the mental foramina is of paramount importance when using implantology to carry out oral rehabilitation procedures not affecting crucial anatomic structures. Panoramic radiography has become the imaging method of choice in many of these cases because of its lower cost and the fact that with it a general assessment of the maxillofacial complex can be made. This study set out to evaluate the distance between the mental foramina and the relationship between them and the mandibular base, and the posterior border of the mandible ramus, as well as the relationship between the bilateral mandibular foramina. The morphometric procedures were carried out by three examiners experienced in Dental Radiology, firstly on 58 human mandibles, with the aid of digital calipers and then on the respective panoramic radiographs of the mandibles, with Image J software, with and without the aid of artificial markers for delimitating the areas of interest. Using Friedman's statistical analysis, there were statistically significant differences between various measurements analyzed and compared to the gold standard, which points to the need to use more accurate imaging tests.

A localização precisa do forame mentoniano tornou-se uma necessidade premente para a execução de procedimentos de reabilitações orais, empregando a implantodontia, que não afetem estruturas anatômicas importantes, sendo a radiografia panorâmica o método de imagem de escolha em muitos desses casos por ter baixo custo e pela possibilidade de avaliação geral do complexo maxilo facial. Este trabalho teve como objetivo avaliar a distância entre os forames mentonianos e a sua relação com a base mandibular, borda posterior do ramo da mandíbula e a relação entre os forames mandibulares bilateralmente. As morfometrias foram realizadas por três experientes avaliadores em Radiologia Odontológica, primeiramente em 58 mandíbulas humanas, com o auxílio de paquímetro digital e depois nas respectivas radiografias panorâmicas das mandíbulas, com o software Image J, com e sem o auxílio de marcadores artificiais para delimitação das áreas de interesse. Por meio da utilização da análise estatística de Friedman, observaram-se diferenças estatísticas significativas em diversas medidas analisadas, quando comparadas ao padrão ouro, fato que demonstra a necessidade da utilização de exames por imagem mais precisos.

Orthodontic Extrusion of the Upper Central Incisor: A Rare Case of Pulp Mummification / Extrusión Ortodóncica del Incisivo Central Superior: un Caso Raro de Momificación Pulpar

Due to its anatomical positioning, the central upper incisors are the most affected teeth when related to trauma injuries in the craniofacial region, among with nose traumas. In childhood, traumatic injury is most often caused by bicycle accidents, sports, recreational activities or falls. The aim of this report is to describe a treatment for intrusion of the left maxillary central incisor and the subsequent complications in an 8-year-old boy. Also, the report emphasizes the importance of careful long-term follow-up monitoring intruded permanent teeth. Pulp tissue, as other tissues in the human body, tends to change with traumas. Some of those changes are natural while others occur as result of injuries to the dentin-pulp complex such as caries lesions, periodontal disease, calcifications, as in the present report, or restorative dental procedures. Normally conducted endodontic treatment must take place to obtain maximal results, but only after the re-stabilization of the tooth.

Debido a su localización anatómica, los incisivos centrales superiores son los dientes más afectados cuando se refieren a las lesiones traumáticas de la región craneofacial, entre los traumas nasales. En la infancia, lesión traumática suele ser ocasionado por accidentes de bicicleta, deportes, actividades recreativas o caídas. El objetivo de este artículo es describir un tratamiento para la intrusión del incisivo central superior izquierdo y las complicaciones posteriores en un niño de 8 años de edad. Asimismo, el informe hace hincapié en la importancia de cuidado a largo plazo con un seguimiento intrusión dientes permanentes. Tejido de la pulpa, como otros tejidos en el cuerpo humano, tiende a cambiar con traumas. Algunos de estos cambios son naturales, mientras que otros se producen como consecuencia de las lesiones del complejo dentina-pulpa, como las lesiones de caries, enfermedad periodontal, calcificaciones, como en el presente informe, restauración o intervención dental. Tratamiento endodóntico a cabo normalmente deben tener lugar para obtener los máximos resultados, pero sólo después de la re-estabilización del diente.

Cross-sectional study of correlation between mandibular incisor crowding and third molars in young Brazilians

Objectives: The aim of this study was to evaluate transversally the clinical correlation between lower incisor crowding and mandible third molar. Study Design: Three hundred healthy volunteers (134 male and 16666 female), aged 20.4 (±2.4) years-old were submitted to a complete clinical examination and filled up a questionnaire about gender, age, total teeth number and presence or absence of superior and inferior third molar. After a recent panoramic radiography were evaluated. The multiple logistic regression showed that none of the studied factors influenced the mandibular incisor crowding. Results: The proportion of both molars present or both absent was higher than the other conditions (Chi-square, p<.0001). The multiple logistic regression showed that any of the studied factors, influenced (p>.05) the mandibular incisor crowding. Despite the statistical significance, wear orthodontics appliances showed a little correlation(odds ratios < 1.0) in the mandibular incisor crowding. Conclusion: Presence of maxillary and/or mandibular third molars has no relation with the lower incisor crowding (AU)