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Próteses personalizadas de Articulação Temporomandibular (ATM) são desenvolvidas para cada paciente, possuindo um planejamento multidisciplinar para a melhor recuperação dos movimentos e das funções básicas. Essa solução multidisciplinar integra ferramentas da engenharia, técnicas avançadas de cirurgia médica, tomografia computadorizada, simulações computacionais, ensaios mecânicos e técnicas de produção para obter uma perfeita adaptação à região do corpo que se deseja substituir, integrando aspectos funcionais tais como proteção, ajuste, forma e resistência mecânica no design da peça anatômica a ser implantada. No Brasil, prótese personalizada de ATM, através da resolução RDC nº305 de 2019 estabelece os requisitos para os fabricantes de dispositivos médicos e exige notificação de cada produto personalizado fabricado. Porém, não especifica normas para ensaio de ATM e a ausência de resultados que deem suporte aos órgãos de fiscalização. O objetivo do presente trabalho foi o desenvolvimento de uma prótese personalizada de ATM e a análise (estática e de fadiga) pelo método dos elementos finitos e ensaios mecânicos, e demonstrar o potencial uso do método de elementos finitos como auxiliar no projeto e confecção de próteses de ATM. Através do caso mais crítico, baseado na literatura, foi definida a maior força de mordida com 300N e que a prótese deveria suportar 5 milhões de ciclos, o ensaio estático foi capaz de suportar, em média, uma carga de 802.2N e o ensaio de fadiga atingiu o critério de runout com 320N. Os resultados gerados demonstraram que com o uso da análise por elementos finitos pode-se ter uma previsibilidade que a prótese suportaria os esforços e confirmado com os ensaios mecânicos em laboratório, auxiliando na validação deste método para a obtenção da prótese de ATM, servindo como dados auxiliares aos órgãos de fiscalização e possibilitando a utilização dos dados para desenvolvimento de novas próteses. Custom Temporomandibular Joint (TMJ) prostheses are developed for each patient, with multidisciplinary planning for better recovery of basic movements and functions. This planning integrates engineering tools, advanced medical surgery techniques, computed tomography, computer simulations, mechanical tests and production techniques to achieve a perfect adaptation to the desired body region, integrating functional aspects such as protection, shape and mechanical resistance in the design of the anatomical part to be implanted. In Brazil, a sanitary legal instrument RDC No. 305 of 2019 establishes the requirements for medical device manufacturers and turns mandatory notification of each customized product manufactured. However, it does not specify the stardards for TMJ tests and the absence of results that gives support to the inspection authorities. The objectives of this work were the development and manufacture of a customized TMJ prosthesis, and to demonstrate the potential use of the finite element method as an aid in the design of TMJ prostheses. To achieve this, the static and the fatigue analysis were realized using the finite element method and mechanical tests were performed to complement the results. The most critical case was standardized on bite force at 300N and that the prosthesis should handle it in 5 million cycles. The static test has shown that the prosthesis was able to handle, on average, 802.2N load. The fatigue test showed that the prosthesis reached out the criteria of run out at 320N. The generated results demonstrated that the finite element analysis can predict the probable foible region to the prosthesis along with laboratory mechanical tests, supporting the validation of this method to obtain the TMJ prosthesis. Plus, it could be used as support to inspection authorities and as a data generator to develop new prostheses.

Alloplastic replacement of the temporomandibular joint (TMJ) is the treatment of choice in cases of TMJ end-stage disease. Improvements in computer-aided design/computer-aided manufacturing (CAD/CAM) translated into the possibility ongf designi very precise TMJ prostheses based on the anatomy of each single patient. Custom-made TMJ prostheses are described in the most recent literature and provide facilitations in terms of ease of placement and accuracy. Although before the era of custom-made surgical guides, they did not play a prominent role in the field of TMJ surgery, their use has become mandatory when custom-made prostheses are used. Surgical guides, generally known also as cutting guides, allow the subcondylar bone cut to be performed according to the exact shape and size of the planned prostheses. Additionally, they allow the predrilling of fixation holes in the mandible to minimize errors in prostheses positioning. However, the design of surgical guides did not evolve over time as much as prostheses did. In this paper the authors critically analysed literature on this topic and described the improvements of surgical guides over time. Moreover, based on the findings of literature research, a new cutting guide system was developed and is proposed in this article.

The dislocation of the mandibular condyle in the middle cranial fossa is a rare condition with few reports in the literature. The authors described the first case reported of unilateral dislocation and fracture treated and reconstructed with a Temporo mandibular joint prostheses. Pre-surgical conduct, medical positions of the Neurosurgery, Radiology and Oral and Maxillofacial teams are described. Also, two years post-operative evaluations are detailed, including information regarding maximum interincisal opening, function, speech, pain and diet of the patient.

La incapacidad de desarrollar sistemas inertes eficaces para la sustitución completa de la articulación temporo-mandibular durante décadas ha generado una variedad de soluciones biológicas para un problema biomecánico. Los injertos autólogos no ofrecen garantías en funcionalidad, simetría, o estabilidad oclusal; resultan técnicamente más complejos y tienen mayor potencial morbilidad. El paciente candidato a reconstrucción completa de la ATM debe contar con la posibilidad de una prótesis si otras opciones fracasan. La reconstrucción aloplástica garantiza estabilidad oclusal, técnica sencilla y reproducible, estancia hospitalaria predecible y baja tasa de complicaciones con los sistemas protésicos actuales. Siempre van a existir pacientes en los que ésta sea la única opción, por lo tanto es primordial la medición de la magnitud de las fuerzas implicadas en la mecánica de la ATM para poder diseñar prótesis en base a modelos fiables como en otras articulaciones en las que ya han resuelto el problema.Incapabability to develop effective inert systems to total temporomandibular joint substitution during decades has genered several biologic solutions for a biomecanic question. Autologous grafts don´t offer security in functioning, simmetry, or oclusal estability; its have more coplex technique and more potencial morbility. Alloplastic reconstruction guarantees oclusal stability, single and reproducible technique, predictable time in hospital, and low morbility with actual prosthetic systems. Patients whos prostheses is only one option are going to exist always, so that it is primordial measures of magnitude of implicated strenghts in TMJ mecanic to can design prosthesis based on reliable models like others articulations which have just resolved the question.

The dislocation of the mandibular condyle in the middle cranial fossa is a rare condition with few reports in the literature. The authors described the first case reported of unilateral dislocation and fracture treated and reconstructed with a Temporo mandibular joint prostheses. Pre-surgical conduct, medical positions of the Neurosurgery, Radiology and Oral and Maxillofacial teams are described. Also, two years post-operative evaluations are detailed, including information regarding maximum interincisal opening, function, speech, pain and diet of the patient. La luxación del cóndilo mandibular con impactación en la fosa craneal media es un proceso poco frecuente -apenas se dispone de estudios publicados. Los autores describen el primer caso publicado de luxación y fractura unilateral combinadas, tratado y reconstruido con la implantación de una prótesis temporomandibular. Se describen la conducta prequirúrgica y la postura médica de los equipos de neurocirugía, radiología y cirugía oral y maxilofacial. Se proporcionan detalles de las evaluaciones de los 2 primeros años postoperatorios, incluidos la abertura máxima interincisal, función articular, habla, sintomatología dolorosa y alimentación del paciente.

In the international literatura exist some information related to temporomandibular joint (TMJ) involvement in condylar fracture malunion; the treatment is variated being executed with a bone reconstruction, ramus vertical osteotomy or condilar plate. This case demonstrates that TMJ replacement with prosthetic joint is technically possible and appropriate in the case of malunion of condylar fracture.

La incapacidad de desarrollar sistemas inertes eficaces para la sustitución completa de la articulación temporo-mandibular durante décadas ha generado una variedad de soluciones biológicas para un problema biomecánico. Los injertos autólogos no ofrecen garantías en funcionalidad, simetría, o estabilidad oclusal; resultan técnicamente más complejos y tienen mayor potencial morbilidad. El paciente candidato a reconstrucción completa de la ATM debe contar con la posibilidad de una prótesis si otras opciones fracasan. La reconstrucción aloplástica garantiza estabilidad oclusal, técnica sencilla y reproducible, estancia hospitalaria predecible y baja tasa de complicaciones con los sistemas protésicos actuales. Siempre van a existir pacientes en los que ésta sea la única opción, por lo tanto es primordial la medición de la magnitud de las fuerzas implicadas en la mecánica de la ATM para poder diseñar prótesis en base a modelos fiables como en otras articulaciones en las que ya han resuelto el problema. Incapabability to develop effective inert systems to total temporomandibular joint substitution during decades has genered several biologic solutions for a biomecanic question. Autologous grafts don´t offer security in functioning, simmetry, or oclusal estability; its have more coplex technique and more potencial morbility. Alloplastic reconstruction guarantees oclusal stability, single and reproducible technique, predictable time in hospital, and low morbility with actual prosthetic systems. Patients whos prostheses is only one option are going to exist always, so that it is primordial measures of magnitude of implicated strenghts in TMJ mecanic to can design prosthesis based on reliable models like others articulations which have just resolved the question.