Resistencia estructural de prótesis dentales acrílicas y de cromo cobalto en cadáveres quemados o carbonizados: a propósito de dos casos / Structural resistance of acrylic and cobalt-chromium dental prostheses in burned or charred corpses: a propos of two cases

La identificación humana genera continuos desafíos técnicos y científicos para los equipos de expertos forenses en sus múltiples contextos de intervención. Uno de los más complejos, está representado por el hallazgo de cadáveres quemados o carbonizados, donde las huellas dactilares resultan inviables. En tales situaciones, los tejidos de la cavidad oral han demostrado elevada tolerancia a la injuria térmica, aportando información decisiva, muchas veces com-plementada por estructuras protésicas recupera-das del occiso. El presente artículo reporta dos ca-sos donde las prótesis dentales acrílicas y de cromo cobalto exhibieron notable indemnidad pese a la gran pérdida orgánica sufrida por los cuerpos de las víc-timas ante la acción vulnerante del fuego, otorgando valor probatorio para contribuir en el establecimien-to de su identidad (AU)

Human identification generates continuous technical and scientific challenges for teams of forensic experts in their multiple contexts of intervention. One of the most complex is represented by the discovery of burned or charred corpses, where fingerprints are unviable. In such situations, the tissues of the oral cavity have shown high tolerance to thermal injury, providing decisive information, often complemented by prosthetic structures recovered from the deceased. This article reports two cases where the acrylic and cobalt chrome dental prostheses presented notable indemnity despite the great organic loss suffered by the bodies of the victims before the damaging action of fire, granting probative value to contribute to the establishment of their identity (AU)

In Vitro Microscopic Evaluation of Metal- And Zirconium-Oxide-Based Crowns' Marginal Fit

ABSTRACT Objective To evaluate the marginal adaptation of computer-aided designing and computer-aided machining (CAD/CAM) fabricated cobalt-chromium and zirconium-oxide-based ceramic crowns compared to those produced by a conventional method. Material and Methods The study consists of three groups; 45 crowns fabricated from cobalt-chromium (CAD-CoCr) and 45 crowns manufactured from zirconium CAD/CAM technology (CAD-Z), and 45 control (C) which consists of conventional metal-ceramic crowns. The marginal discrepancies in vertical dimensions were assessed utilizing a microscope in four surfaces (mesial, distal, vestibular, and oral) for each crown. On completion of the microscopic evaluation, multivariate analysis of variance (MANOVA) was used to study the difference in the four surfaces, considered altogether. Two-way ANOVA revealed the effect of three systems used for gap measurements of each landmark. The differences observed were considered significant at p<0.05. Results There were no differences in the four surfaces revealed by АNOVА in the three groups when considered altogether. Two-way ANOVA of each surface discovered no differences among all groups as well. Conclusion The CAD/CAM crowns revealed a comparable and satisfactory marginal adaptation compared to conventional metal-ceramic crowns.

Brazilian Adults Believe that Complete Dentures would be the Solution to the Oral Impacts Caused by Reduced Dentition

Abstract Objective: To evaluate the direct and oral impact-mediated association between reduced dentitions and the self-perceived need for complete dentures (CD) in dentate adults. Material and Methods: Data from the Brazilian Oral Health Survey (2010) were analyzed. The outcome was self-perceived need for CD. Functional dentition (FDClassV) was defined by the presence of the following criteria: level I - ≥1 tooth in each arch, level II - 10 teeth in each arch, level III - 12 anterior teeth, level IV - ≥ 3 posterior occluding pairs (POPs) of premolars and level V - ≥1 bilateral POPs of molars. Oral impacts were assessed with Oral Impacts on Daily Performances scale. Results: FDClassV was associated with a less self-perceived need for CD both directly and mediated by oral impacts. Dentitions without level V were associated with the outcome mediated by oral impacts. Between individuals with 10 teeth in each arch, self-perceived need for CD was similar for those who had or not anterior teeth and POPs. Individuals with <10 teeth in each arch and level III did not have a higher frequency of self-perceived need for CD compared to those with level II. Conclusion: Oral impacts mediated the association between reduced dentitions and self-perceived need for CD. Individuals with tooth loss may report need for CD, even when they have dental configurations compatible with functionality.

The Prosthetic Management of a Case of Epulis Fissuratum by a Novel Technique / El manejo protésico de un caso de épulis fisurado con una técnica novedosa

ABSTRACT: The clinical management of the epulis involves the elimination of causal factors, excision of fibrous tissue excess accompanied by an appropriate prosthetic rehabilitation. The confection of interim prosthesis or the rectification of old prosthesis for the setting up of a tissue conditioner if necessary, to improve the healing and prevent the decrease of the vestibule depth after the surgical exeresis. Throughout this paper, we are going to present a new technique for the correction of old prostheses poorly adapted for the management of a case of the epulis fissuratum.

RESUMEN: El manejo clínico de un épulis comprende la eliminación de los agentes causales y la eliminación del tejido fibroso, acompañado de una adecuada rehabilitación protésica. Es necesaria la confección de una prótesis provisional o la rectificación de la prótesis vieja, para la colocación del acondicionador de tejidos si fuera necesario para mejorar el sanado y prevenir la disminución de la profundidad del vestíbulo después de la exéresis quirúrgica. En este artículo, presentaremos una nueva técnica para la corrección de la prótesis desajustada en el manejo de un caso de épulis fisurado.

Self-Perception on the Institutionalized Elderly Need of Dental Prosthesis

Abstract Objective: To make an association between self-perception and the implementation of sociodemographic variables for the autonomous and / or partially dependent individuals in nursing homes. Material and Methods: Epidemiological, observational and cross-sectional study. The sample consisted of 208 institutionalized elderly, both sexes, 60 years old or older, independent or partially dependent, randomly selected from two long-term residential institutions. Subjective evaluation: self-perception questionnaire, Geriatric Oral Health Assessment Index, quality of life assessment, Oral Impacts on Daily Performance (OIDP), oral health self-assessment (OH) and the need for dental prostheses. Bivariate analysis, chi-square test and multiple logistic regression were used, with the variables with p<0.05 remaining in the model. Results: Men were edentulous (53.43%), 68.75% used some type of denture, and 64.91% required dental prostheses, 60.58% self-assessed (OH) as good / excellent; who reported a need for dental prostheses presented 6.7 times (95% CI: 3.2-14.3) and more likely to have an impact on OIDP, those who needed prosthetics had a 2.8 times chance (95% CI: 1.3-6.1) (p<0.0001). The self-reported need for prostheses was associated with prevalence severity of impacts on QoL, eating, pronounce words correctly, Smile without feeling embarrassed; and the main reasons for not having badly adjusted teeth / dentures. Conclusion: The institutionalized elderly self-perceive the need for dental prostheses, but it does not have a negative impact on quality of life.

Tiempo de elaboración y grado de deformidad de la placa base termoformada, en comparación con la placa base de acrílico de autopolimerización / Development time and the deformity degree of the thermoformed base plate compared to the acrylic base plate of self-polymerization

Resumen Introducción: En la actualidad existen diversos tipos de materiales para la confección de placas bases, como procedimiento para la confección de prótesis dentales. La opción de la lámina de termoformado actualmente es de poco uso, el acrílico de autopolimerización es un material de uso diario en consulta. Objetivo: Comparar las técnicas de confección de placas bases, para determinar cuál de las dos brinda cualidades como menor tiempo de elaboración y menor deformidad. Materiales y métodos: Se seleccionaron por conveniencia 20 modelos de yeso totalmente edéntulos, a los cuales se registra tiempo de elaboración y se les aplican las mismas pruebas de laboratorio. Resultados: Las placas bases termoformadas presentan un tiempo medio de 7 minutos, mientras que las placas bases de acrílico de autopolimerización muestran un tiempo medio de 29 minutos, con base en los análisis de laboratorio la menor deformación se presenta en la placa base de acrílico de autopolimerización. Conclusión: El tiempo de elaboración de la placa base termoformable es menor, mientras que la deformación es mayor en comparación con la de la placa base de autopolimerización, y esta última a su vez, presenta mayor tiempo de elaboración que el de la placa base termoformable.

Abstract Introduction: Currently there are different types of materials for the preparation of base plates, as a procedure for the preparation of dental prostheses. The option of the thermoforming sheet, which is currently of little use, as well as, of self-curing acrylic, a material of daily use in consultation. Objective: To compare the techniques for making base plates, to determine which of the two provide qualities such as shorter processing time and less deformity. Materials and methods: 20 models of gypsum totally edentulous were selected for convenience, to which processing time is recorded and the same laboratory tests are applied. Results: The thermoformed base plates have an average time of 7 minutes, while the self-polymerized acrylic base plates have an average time of 29 minutes, based on the laboratory analysis the least deformation occurs in the acrylic base plate of autopolimerization. Conclusion: The time of preparation of the thermoformable base plate is less, while the deformation is greater compared to the base plate of self-polymerizatíon, the latter in turn, has a longer processing time than the thermoformable base plate.

The use of Myerson Duracetal Obturators In the Rehabilitation of Maxillary Resection Defects

Myerson Duracetal, was used for the fabrication of Obturator Prostheses in four (4) patients. The steps in fabrication are outlined. The patients' perception of function as assessed using the Obturator Function Scale (Table 1) is also presented. Despite technical challenges, Myerson Duracetal was successfully used in fabrication of light, stable, retentive, aesthetic prostheses which could be adapted to the evolving defects.

Agenesis of maxillary lateral incisor in an Angle Class II, Division 1 malocclusion patient.

The present case report describes the orthodontic treatment of a patient with agenesis of maxillary left lateral incisor and Angle Class II, Division 1 malocclusion. The patient also presented with maxillary midline deviation and inclination of the occlusal plane in the anterior region. Treatment objectives were: correction of sagittal relationship between the maxilla and the mandible; correction of midline deviation, so as to cause maxillary and mandibular midlines to coincide; correction of overbite and leveling of the occlusal plane, so as to create ideal conditions for esthetic rehabilitation of anterior teeth. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as a requirement for the title of certified by the BBO.

Agenesis of maxillary lateral incisor in an Angle Class II, Division 1 malocclusion patient

The present case report describes the orthodontic treatment of a patient with agenesis of maxillary left lateral incisor and Angle Class II, Division 1 malocclusion. The patient also presented with maxillary midline deviation and inclination of the occlusal plane in the anterior region. Treatment objectives were: correction of sagittal relationship between the maxilla and the mandible; correction of midline deviation, so as to cause maxillary and mandibular midlines to coincide; correction of overbite and leveling of the occlusal plane, so as to create ideal conditions for esthetic rehabilitation of anterior teeth. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO) as a requirement for the title of certified by the BBO.

O presente caso clínico relata o tratamento ortodôntico de um paciente portador de agenesia do incisivo lateral superior esquerdo e má oclusão de Classe II 1a divisão de Angle. Apresentava, ainda, desvio da linha média superior e inclinação do plano oclusal na região anterior. Os objetivos do tratamento foram adequar a relação sagital entre as arcadas, proporcionar a coincidência entre as linhas médias superior e inferior, corrigir a sobremordida e nivelar o plano oclusal, criando condições apropriadas para a reabilitação estética dos dentes anteriores. Este caso foi apresentado à Diretoria do Board Brasileiro de Ortodontia e Ortopedia Facial (BBO) como parte dos requisitos para a obtenção do título de Diplomado pelo BBO.

Uso de prótese dentária e sua relação com lesões bucais / Use of dental prostheses and their relationship with oral lesions / Uso de prótesis dentales y su relación con lesiones orales

Objetivo Mostrar a relação da prótese dentária com a incidência e o tipo de lesões bucais desenvolvidos na região do Seridó, estado do Rio Grande do Norte, Brasil. Método Foi realizado um cadastro de 77 pacientes, todos com mais de 21 anos de idade, ambos os gêneros, não etilistas e/ou tabagistas crônicos, residentes nos municípios correspondentes a região do Seridó, que apresentavam algum tipo de lesão bucal e que deram entrada nas Clínicas Odontológicas da Universidade do Rio Grande do Norte, sendo observado a relação destas com o uso de próteses dentárias. Resultados A maioria das próteses relacionadas com lesões orais possuía mais de 05 anos de uso e indicação de troca, e que a Candidose, com 45,5 % dos casos e Hiperplasia fibrosa inflamatória, com 27,2 % foram às lesões mais relacionadas. Conclusões As próteses dentárias totais e parciais removíveis apresentaram relação com lesões orais, no entanto, a prótese total apresentou maior percentual de peças indicadas para troca e com mais de 05 anos de uso; mostrando que o tipo parcial removível a grampo mesmo sem indicações de troca, apresentaram uma alta relação com lesões.(AU)

Objective To show the relationship between dental prostheses and the incidence and type of oral lesions developed in the Seridó region of Brazil. Methods 77 patients were registered. All were over 21 years of age, of both sexes, non-alcoholic and / or chronic smokers, and residents of the municipalities of the region corresponding to Seridó. They also all had some type of oral lesion and had been admitted to dental clinics of the University of Rio Grande do Norte. Here, the relationship between these lesions and the dental prostheses that they used was observed. Results The majority of dental prostheses related to oral lesions had more than 5 years of use and required changing. Candidiasis (45.5 %) and inflammatory fibrous hyperplasia (27.2 %) were the lesions most related to the dental prostheses. Conclusions Complete prostheses and removable partial dentures correlated with oral lesions. However, the complete prostheses had a higher percentage ready for change-out and had more than 05 years of use. This demonstrates that removable partial dentures, even without the need for exchange, showed a high correlation with the oral lesions.(AU)

Objetivo Mostrar la relación de prótesis dentales con la incidencia y el tipo de lesiones orales desarrollados en la región Seridó, estado de Rio Grande do Norte, Brasil. Método Se realizó un registro de 77 pacientes. Todos eran mayores de 21 años de edad, de ambos sexos, no alcohólicos y/o fumadores crónicos, residentes de los condados correspondientes a la región Seridó, que tenía algún tipo de lesión oral y que fueron admitidos a clínicas dentales de la Universidad de Río Grande del Norte. Allí se observó la relación de estas lesiones con el uso de las prótesis dentales. Resultados En la mayoría de los casos de lesiones orales, estaban relacionadas prótesis que tenían más de 5 años de uso y requerían ser cambiadas. La candidiasis, con el 45,5 % de los casos, y la hiperplasia fibrosa inflamatoria, con el 27,2 %, fueron las lesiones más relacionadas. Conclusiones Se concluye que las prótesis completas y las prótesis parciales removibles mostraron una relación con lesiones orales. Sin embargo, las prótesis completas tuvieron un mayor porcentaje para ser cambiadas y con más de 5 años de uso. Esto demuestra que el tipo parcial removible, incluso sin necesidad de cambio, mostraron una alta correlación con las lesiones.(AU)

Estudo da soldagem a laser em próteses odontológicas / Laser welding dental prosthesis abstract

O objetivo deste trabalho é apresentar uma revisão de literatura sobre a soldagem a laser em próteses odontológicas. A soldagem a lase passou a ser utilizada na odontologia para a confecção de próteses fixas a partir da década de 70...

Avaliação da precisão do articulador semiajustável a7fix / Evaluation of the accuracy of semi-adjustable articulator a7fix

Um dos erros mais frequentes em reabilitação oral é a montagem incorreta dos modelos de gesso no articulador. Os modelos de estudo e, principalmente, os modelos de trabalho, devem ser rigorosamente posicionados numa relação funcional no articulador, que irá representar a maxila e a mandíbula com a articulação temporomandibular e os movimentos mandibulares. O objetivo deste trabalho foi avaliar através de um estudo laboratorial a precisão do articulador A7 Fix Bio-Art padronizado, quando simuladores dos modelos são transferidos de um articulador para outro. Para a realização desta pesquisa foram selecionados dez articuladores e desses, um foi designado como articulador mestre. Foram confeccionadas peças que representassem as duas arcadas e essas foram montadas no articulador mestre e transferidos para os outros nove articuladores e avaliado na transferência os seguintes critérios: efetividade do contato com o carbono (avaliação vertical), coincidência dos parafusos com os orifícios (avaliação horizontal), e coincidência do pino incisal com a linha cheia (avaliação vertical). Os resultados encontrados foram de que em todas as transferências os três parafusos do modelo superior coincidiram com as concavidades realizadas no modelo inferior; a relação de contato interoclusal permaneceu em todas as transferências; somente em dois articuladores houve 1 mm de discrepância em relação a linha cheia. Conclui-se que o articulador A7 Fix (Bio-Art) padronizado permitiu o intercâmbio dos modelos de gesso entre os articuladores.

One of the most usual mistakes in oral rehabilitation is the incorrect assemblage of the cast models on the articulating device. The study models and mainly the work models must be strictly placed to a functional relation on the articulator, which will represent the maxilla and the mandible, with the temporomandibular articulation and the mandible movements. This work aims at evaluating, through a laboratorial experimental study, the accuracy of the 7 Fix Bio-Art standardized when the simulators of the models are transferred from one articulator to another. Ten articulators were selected for this study and one of them was chosen as the master articulator. Parts representing the two articulators were manufactured and assembled on the master articulator and transferred to other nine articulators and in the transference the following criterion were evaluated: effectiveness of the contact with the carbon (vertical evaluation), coincidence of the screws with the holes (horizontal evaluation), and coincidence of the incisal pin with the full line (vertical evaluation) the results found at the end of the test were: in all transference of the three screws of the superior model fit the concavities in the inferior model; the relation of the interoclusal contact happened in the proper way in all transference; only in two of the articulators there was a difference of 1 mm in relation to the full line. It was concluded that the standardization of the A7 FIX (Bio-Art) allowed the interchange of the models among the articulators’ devices.

Cavity preparation machine for the standardization of in vitro preparations.

Several in vitro studies employ the confection of cavity preparations that are difficult to standardize by means of manual high speed handpieces. This study presents the development of a cavity preparation machine designed to standardize in vitro cavity preparations. A metal base of 25 mm x 25 mm x 4 mm (length x width x height) was coupled to a small mobile table which was designed to be able to move by means of two precision micrometers (0.01-mm accuracy) in the horizontal directions (right-left, and back-front). A high speed handpiece was coupled to a metallic connecting rod which had an accurate dial indicator enabling control of the vertical movement. The high speed handpiece is also able to move 180 degrees around its longitudinal axis and 360 degrees around its transversal axis. The suggested cavity preparation machine precisely helps in the standardization of cavity preparations for in vitro studies.

Cavity preparation machine for the standardization of in vitro preparations

Several in vitro studies employ the confection of cavity preparations that are difficult to standardize by means of manual high speed handpieces. This study presents the development of a cavity preparation machine designed to standardize in vitro cavity preparations. A metal base of 25 mm x 25 mm x 4 mm (length x width x height) was coupled to a small mobile table which was designed to be able to move by means of two precision micrometers (0.01-mm accuracy) in the horizontal directions (right-left, and back-front). A high speed handpiece was coupled to a metallic connecting rod which had an accurate dial indicator enabling control of the vertical movement. The high speed handpiece is also able to move 180° around its longitudinal axis and 360° around its transversal axis. The suggested cavity preparation machine precisely helps in the standardization of cavity preparations for in vitro studies.

Desinfecção de moldes, modelos e trabalhos protéticos em laboratórios de prótese dentária / Desinfection of molds, stone casts and prosthetic works in dental laboratories

Esta pesquisa teve o objetivo de avaliar como a desinfecção de moldes, modelos e trabalhos é realizada em laboratórios de prótese dentária. Para isso, um questionário foi formulado contendo 6 perguntas objetivas sobre desinfecção e biossegurança. Foram selecionados aleatoriamente 12 laboratórios especializados em prótese dentária da cidade de São Paulo. Os técnicos responsáveis pelo laboratório responderam ao questionário. A conclusão que se pôde chegar foi que os técnicos de laboratório ainda não estão conscientizados sobre os procedimenos relacionados à biossegurança

Comparación de la resistencia a la deformación de dos materiales no metálicos para estructuras de prótesis fija: evaluación por elementos finitos / A comparison of the resistance to deformation of two non-metallic materials for fixed prosthesis frameworks: an evaluation by finite elements

Antecedentes: las restauraciones en cavidad bucal han sido realizadas tradicionalmente en materiales metálicos, los cuales han cumplido con las exigencias mecánicas de forma excelente pero con esporádicos inconvenientes de bicompatibilidad y estética. Nuevos materiales se han desarrollado en la odontología, para soportar las necesidades estéticas y funcionales de las restauraciones parciales y fijas. Para tener un perfil completo, se realizan estudios complementarios con métodos físicos y numéricos en los cuales se evalúan las propiedades físicas y mecánicas con las cuales se puede crear un criterio para utilizar un material como restaurador definitivo. Objetivo: comparar dos materiales, Vectris(R) y Construct(R) en cuanto a resistencia a la deformación, por fuerzas longitudinales y cortantes, al soportar cargas ejercidas sobre una prótesis parcial fija de tres unidades, utilizando el método de elementos finitos. Métodos: se realizaron estructuras de prótesis fija de tres unidades con pilares en 35 y 37 y póntico del 36 con los materiales mencionados, los cuales fueron comparados con una estructura estándar de oro tipo IV. Se hicieron mediciones manuales con calibradores metálicos para obtener las dimensiones de estas estructuras. Se tomaron fotos digitalizadas estandarizadas y se realizaron cortes a las estructuras, para ser llevadas a un programa de graficación en computador (Autocad 2000, Autodesk(R), el cual desarrolló las geométricas a escala. Estas gráficas fueron importadas en el programa Cosmos/M(R), que es el programa de elementos finitos donde se analizaron las fuerzas longitudinales en todas las estructuras y las fuerzas cortantes en los pónticos, mostrando en una serie de tablas los resultados numéricos en Newtons y analizando por medio de distribución de colores los esfuerzos internos de las estructuras de estudio. Resultados: al analizar el comportamiento de flexión y torsión de las estructuras de fibras de vidrio, polietileno y oro tipo IV, se observó que la condición crítica que generó deformación plástica para los materiaoles de estudio, fue de una carga concéntrica de 970 N, 85.1 N, 298 N, respectivamente. Conclusiones: las fibras que mejor comportamiento presentaron frente a las cargas aplicadas y analizadas por elementos finitos fueron las de vidrio