Reconstrução óssea de defeito crítico com a utilização de tela de titânio: relato de caso / Bone reconstruction of a critical defect using titanium mesh: case report / Reconstrucción ósea de un defecto crítico con malla de titanio: reporte de caso

Introdução: O uso de membranas de barreira de exclusão de epitélio para regeneração óssea guiada tem sido apresentado na literatura como abordagem de tratamento bem sucedida, essas barreiras irão impedir a incorporação de células de tecidos moles no enxerto ósseo ou no es paço criado pelo defeito e permitir que apenas as células osteogênicas estejam presentes. Relato de caso: Trata-se de um caso clinico de um paciente que evoluiu com perda óssea significativa por lesão Endo-periodontal levando a perda dentaria, para a reabilitação com implantes se fez necessário uma reconstrução de um defeito crítico com a utilização de tela de titânio para arcabouço ósseo de mistura de enxerto autógeno e biomaterial e recobrimento com membrana de colágeno, o enxerto autógeno foi removido de área doadora na mandíbula e utilizado de forma particulada. Conclusão: As telas de titânio apresentam viabilidade e previsibilidade no aumento ósseo vertical, horizontal e tridimensional em decorrência da sua ampla aplicabilidade, elasticidade, plasticidade adequadas e boas propriedades mecânicas. Avanços na diminuição de suas taxas de exposição e risco de complicações no período de cicatrização melhoram a cada dia a previsibilidade da técnica, bem como a associação com outros materiais como os hemoderivados... (AU)

Introduction: The use of epithelial exclusion barrier membranes for guided bone regeneration has been presented in the literature as a successful treatment approach, these barriers will prevent the incorporation of soft tissue cells into the bone graft or the space created by the defect and allow that only osteogenic cells are present. Case report: This is a clinical case of a patient who evolved with significant bone loss due to an endo-periodontal lesion leading to tooth loss, for rehabilitation with implants it was necessary to reconstruct a critical defect using mesh titanium for bone framework of mixture of autogenous graft and biomaterial and covering with collagen membrane, the autogenous graft was removed from the donor area in the mandible and used in a particulate form. Conclusion: Titanium meshes are viable and predictable in vertical, horizontal and three-dimensional bone augmentation due to their wide applicability, adequate elasticity and plasticity, good mechanical properties. Advances in reducing their exposure rates and risk of complications during the healing period improve the predictability of the technique every day, as well as the association with other materials such as blood products... (AU)

Introducción: El uso de membranas de barrera de exclusión epitelial para la regeneración ósea guiada se ha presentado en la literatura como un enfoque de tratamiento exitoso, estas barreras evitarán la incorporación de células de tejido blando al injerto óseo o el espacio creado por el defecto y permitirán que solo presencia de células osteogénicas. Reporte de caso: Este es un caso clínico de un paciente que evolucionó con una pérdida ósea importante debido a una lesión endo-periodontal que lo llevó a la pérdida de un diente, para rehabilitación con implantes fue necesario reconstruir un defecto crítico utilizando malla de titanio para armazón óseo de mezcla de injerto autógeno y biomaterial y cubriendo con membrana de colágeno, el injerto autógeno se extrajo del área donante en la mandíbula y se usó en forma de partículas. Conclusión: Las mallas de titanio son viables y predecibles en el aumento óseo vertical, horizontal y tridimensional debido a su amplia aplicabilidad, adecuada elasticidad y plasticidad, buenas propiedades mecánicas. Los avances en la reducción de sus tasas de exposición y riesgo de complicaciones durante el periodo de cicatrización mejoran día a día la predictibilidad de la técnica, así como la asociación con otros materiales como los hemoderivados... (AU)

Reconstruction Plate Fracture: Mechanism and Recent Advances

Reconstruction plates with or without bone grafts are used to restore mandibular continuity, form and function following segmental resection of mandible. Fracture of reconstruction plate is observed in 2.9 % to 10% of cases reported in the literature excluding other complications. In this case, we report the fracture of stainless steel reconstruction plate used without bone graft and its management using locking reconstruction plate with non vascularised iliac crest graft following removal of the fractured plate. Review of literature describing incidence, pattern and causes of reconstruction plate fracture and its management is discussed.

Simultaneous innervated and vascularized iliac bone flap for reconstructing mandible and nerve defects / 口腔疾病防治

@#The functional reconstruction of large maxillofacial defects is a major issue in oral and maxillofacial surgery, and autologous bone transplantation is the main method. However, bone is readily absorbed following an autologous bone transplant. Even with vascular anastomosis, spontaneous osteoporosis of transplanted bone is still serious, which affects dental implantation and functional recovery. Therefore, osteoporosis of the grafted bone has become one of the main complications of jaw reconstruction, and there is no preventive measure. The problem that autologous bone with sufficient blood supply cannot avoid osteoporosis suggests that systemic factors such as nerves, which have been neglected in traditional methods, may regulate the internal environment of the transplanted bone. Based on previous studies on the regulation of mesenchymal stem cells by the neural microenvironment, we initiated a new surgical procedure for innervated and vascularized iliac bone flaps based on animal model and cadaver studies. In the innervated and vascularized iliac bone flap, vascular microanastomosis was performed in conjunction with microneuronal anastomosis between the simultaneously harvested ilioinguinal nerve (which innervates the iliac bone and is usually sacrificed and neglected in the conventional vascularized iliac bone flap) and the inferior alveolar nerve proximally and with the mental nerve distally. By conducting clinical retrospective studies and prospective randomized controlled trials, we proved that the novel method of simultaneous innervated iliac bone transplantation can not only prevent bone resorption but also restore the sensation of adjacent soft tissues such as the lip. This may solve the key problems of sensory loss and osteoporosis after mandibular reconstruction, ensure the success of dental implant dentures, and put forward the new concept of "blood supply + innervation" bi-system bone transplantation.

Donor Site Morbidity of Nonvascularized Bone Graft: A Systematic Review

ABSTRACT Objective: To evaluate the donor site morbidity of iliac and fibular nonvascularized bone graft after mandibular resection. Material and Methods: This study was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) in PubMed, Proquest, Science Direct, and Ebsco. A total of 12 studies met the criteria of studies in humans using iliac and fibular nonvascularized bone grafts in mandibular reconstruction after mandibular resection. Results: A greater proportion of patients received iliac nonvascularized bone graft (88.9%) than fibular nonvascularized bone graft (11.1%). Of the 385 cases of iliac bone graft, 153 cases (40%) experienced complications at the iliac donor site, whereas in 48 cases of fibular bone graft, two (4%) experienced complications at the donor site. Hemorrhage, bone fracture, infection requiring debridement, and hematoma were the major complications. Conclusion: The morbidity rate of the nonvascularized bone graft donor site of the fibula (4%) tended to be lower than that of the ilium (40%). Patient age and defect size were not significantly correlated with the occurrence of morbidity donor sites in either the ilium or fibula.

Combination of surgical techniques and reconstructive devices as an alternative treatment after fibula free flap mandibular reconstruction failure: a case report

Loss of mandibular continuity and functionality in cancer patients undergoing extensive mandible resections is challenging. In these situations, the gold standard treatment is fibula free flap reconstruction. The major challenge occurs when there is a failure of the transplanted fibula. Here we report the case of a patient who underwent right hemimandibulectomy with disarticulation and immediate mandibular reconstruction with a fibula free flap. Subsequently, the flap viability was lost, and there was necrosis of the transplanted bone segment in the short-term follow-up. Considering the best form of rehabilitation for the patient, minimizing the risks of loss and optimizing the reconstructive quality, we opted to install a customized prosthesis including a condylecavity joint component associated with a new free flap and subsequent rehabilitation of the dental occlusion with an implant-supported fixed prosthesis.

Reconstrucción mandibular mediante colgajo miocutáneo de pectoral mayor en carcinoma epidermoide, reporte de caso clínico y revisión de la literatura / Mandibular reconstruction using pectoralis major myocutaneous flap in squamous cell carcinoma, clinical case report and literature review

RESUMEN El carcinoma epidermoide surge del epitelio de la mucosa oral, es frecuente en la quinta y sexta décadas de la vida y está típicamente asociado con factores de riesgo como tabaquismo y el consumo de alcohol. En todo el mundo, la incidencia de cáncer oral es más alta en hombres que en mujeres. El incremento en la incidencia del cáncer en México requiere de un manejo adecuado, como colgajos vascularizados para reparar defectos generados por una hemimandibulectomía con márgenes de seguridad. A pesar de la llegada de injertos de tejido libres vascularizados, el colgajo pectoral mayor miocutáneo sigue siendo un colgajo pediculado ampliamente utilizado para la reconstrucción de defectos de tejidos blandos en la región oral y maxilofacial. Se muestra el protocolo quirúrgico realizado en el Hospital Regional "General Ignacio Zaragoza" ISSSTE para el tratamiento de un carcinoma epidermoide mandibular.

ABSTRACT Squamous cell carcinoma arises from the epithelium of the oral mucosa, common in the fifth and sixth decades of life and is typically associated with risk factors such as smoking and alcohol consumption. Worldwide, the incidence of oral cancer is higher among men than women. The increase in the incidence of cancer in Mexico requires proper management and the use of vascularized flaps to repair defects generated by a hemimandibulectomy with safety margins. Despite the advent of vascularized free tissue grafts, the myocutaneous pectoralis major flap remains a pedunculated flap widely used for the reconstruction of soft tissue defects in the oral and maxillofacial region. The surgical protocol carried out at the ISSSTE "General Ignacio Zaragoza" Regional Hospital for the treatment of mandibular squamous cell carcinoma is shown.

Uso de técnicas de impresión 3D en la reconstrucción mandibular. Una revisión breve / Use of 3D printing techniques in mandibular reconstruction. A brief review / Uso de técnicas de impressão 3D na reconstrução mandibular. Uma breve revisão

Resumen En los últimos años, la tecnología y la medicina han podido complementarse para la optimización de tiempo, conocimientos y recursos, aumentando la posibilidad de tratamientos personalizados en más pacientes. A nivel maxilofacial, la reconstrucción de defectos mandibulares se ha visto en la necesidad de progresar sus técnicas debido a la serie de orígenes que afectan el hueso mandibular de manera drástica, como lesiones traumáticas, cáncer, infecciones, enfermedad congénita u otros, y las innumerables consecuencias tanto estéticas como funcionales, restringiendo significativamente la calidad de vida. El objetivo de este artículo es revisar conceptos básicos del uso de tecnologías de impresión 3D en la reconstrucción mandibular. La impresión 3D ha aparecido en diversos ámbitos, siendo en el área de la medicina, un aporte fundamental para la creación de formas anatómicas de alta precisión con el que se pueden diseñar objetos con reproducción de detalles de manera rápida, luego de una serie de pasos que incluyen la obtención de una imagen radiográfica, uso de software y reparación de archivos, y la obtención de un modelo tridimensional. Los últimos estudios han validado el uso de impresiones 3D para una reconstrucción mandibular, con claros beneficios de costos y calidad de detalles. Es necesario crear un enfoque en las técnicas quirúrgicas utilizadas con un objeto impreso tridimensionalmente y un análisis post operatorio de los pacientes sometidos a estos procedimientos más allá de los detalles técnicos.

Abstract In recent years, technology and medicine have been able to complement each other to optimize time, knowledge and resources, increasing the possibility of personalized treatments in more patients. At the maxillofacial level, the reconstruction of mandibular defects has seen the need to progress its techniques due to the series of origins that drastically affect the mandibular bone, such as traumatic injuries, cancer, infections, congenital disease or others, and the innumerable both aesthetic and functional consequences, significantly restricting the quality of life. The objective of this article is to review basic concepts of the use of 3D printing technologies in mandibular reconstruction. 3D printing has appeared in various fields, being in the area of medicine, a fundamental contribution to the creation of high-precision anatomical shapes with which objects with reproduction of details can be designed quickly, after a series of steps which include obtaining a radiographic image, use of software and file repair, and obtaining a three-dimensional model. The latest studies have validated the use of 3D impressions for mandibular reconstruction, with clear benefits in cost and quality of details. It is necessary to create a focus on the surgical techniques used with a three-dimensional printed object and a post-operative analysis of the patients undergoing these procedures beyond the technical details.

Resumo Nos últimos anos, tecnologia e medicina têm se complementado para otimizar tempo, conhecimento e recursos, aumentando a possibilidade de tratamentos personalizados em mais pacientes. No nível maxilofacial, a reconstrução dos defeitos mandibulares tem visto a necessidade de progredir em suas técnicas devido à série de origens que afetam drasticamente o osso mandibular, como lesões traumáticas, câncer, infecções, doenças congênitas ou outras, e as inúmeras ambas estéticas. e consequências funcionais, restringindo significativamente a qualidade de vida. O objetivo deste artigo é revisar os conceitos básicos do uso das tecnologias de impressão 3D na reconstrução mandibular. A impressão 3D tem surgido em vários campos, sendo na área da medicina uma contribuição fundamental para a criação de formas anatômicas de alta precisão com as quais objetos com reprodução de detalhes podem ser desenhados rapidamente, após uma série de etapas que incluem a obtenção de uma imagem radiográfica, uso de software e reparo de arquivos e obtenção de um modelo tridimensional. Os estudos mais recentes têm validado o uso de impressões 3D para reconstruções mandibulares, com claros benefícios em custo e qualidade de detalhes. É necessário criar um foco nas técnicas cirúrgicas utilizadas com um objeto impresso tridimensional e uma análise pós-operatória dos pacientes submetidos a esses procedimentos para além dos detalhes técnicos.

Injerto de hueso medular de tibia como alternativa para relleno de defectos óseos maxilofaciales / Tibial bone graft as an option for filling maxillofacial bone defects

Objetivos: Demostrar la utilidad y la facilidad técnica del injerto tibial en defectos óseos orales y maxilofaciales, para tenerlo como un recurso alternativo en la práctica general del cirujano oral y maxilofacial. Caso clínico: Se presenta un caso clínico con el uso de injerto óseo autólogo de tibia para el relleno de un defecto óseo a raíz de una lesión quística. Se realizó la exéresis de la patología quística por medio de un abordaje oral y posteriormente se recolectó hueso medular tibial a través de un abordaje medio al tubérculo anterior de la tibia, para poder colocarlo en el defecto óseo. Conclusión: El injerto de hueso medular de epífisis tibial representa un sitio de recolección de fácil acceso, del que se puede obtener una cantidad de hueso ideal para defectos de pequeño y mediano tamaño de la región maxilofacial, de baja morbilidad y con muy pocas complicaciones post-operatorias, lo que lo convierte en una alternativa para rellenos de cavidades óseas de gran utilidad (AU)

Objective: To demonstrate the utility and technical ease of the tibial graft in oral and maxillofacial bone defects so as to have it as an alternative resource in the general practice of the oral and maxillofacial surgeon. Case report: A clinical case is shown with the use of an autologous tibial bone graft to fill a bone defect as a result of a cystic lesion. The cyst was excised by an oral approach and the medial tibial bone was collected through a middle approach to the anterior tubercle of the tibia, to place it in the bone defect. Conclusion: The tibial epiphysis medullary bone graft represents an easily accessible collection site, from which an ideal amount of bone can be obtained for small and mediumsized defects of the maxillofacial region, with low morbidity and very few post-operative complications, which makes it a useful option for bone cavity filling (AU)

Reemplazo mandibular con prótesis personalizada de titanio posterior a la exéresis de ameloblastoma / Mandibular replacement with a customized titanium prosthesis after ameloblastoma excision

Introducción: El ameloblastoma es un tumor odontogénico epitelial benigno con tendencia a la recurrencia local si no se elimina adecuadamente. Las alternativas reconstructivas incluyen el uso de colgajos libres microvascularizados, placas y prótesis personalizada de titanio. Objetivo: Describir un reemplazo hemimandibular con prótesis personalizada de titanio posterior a la exéresis de ameloblastoma. Presentación del caso: Mujer de 44 años de edad, que presentó un hallazgo radiográfico durante la realización de tratamiento pulporradicular del diente número 37. Al realizársele el reconocimiento físico facial mostró aumento de volumen en región geniana izquierda mientras que el examen intrabucal detectó expansión de las corticales en la arcada posteroinferior del mismo lado. Se realizó una radiografía panorámica y tomografía axial computarizada con la que se constató la presencia de imagen radiolúcida, multiloculada, en forma de "pompas de jabón" extendiéndose desde el cuerpo mandibular hasta el cóndilo del lado izquierdo. Se tomó muestra para biopsia, con la cual se constató que se trataba de ameloblastoma con patrón folicular. Se realizó abordaje cervical, segmentaria mandibular con margen de seguridad y exarticulación. Se reemplazó la porción eliminada con prótesis personalizada de titanio. Se mantuvo el chequeo posoperatorio en el que se comprobó una buena evolución. Conclusiones: La cirugía constituyó el pilar de tratamiento utilizado. Una vez realizada la resección quirúrgica se reconstruyó el defecto con prótesis personalizada de titanio, proceder de gran novedad en nuestro medio y útil para restablecer la función y estética(AU)

Introduction: Ameloblastoma is a benign tumor of odontogenic epithelium with a tendency to local recurrence if not removed appropriately. Reconstruction alternatives include the use of microvascularized free flaps, plates and customized titanium prostheses. Objective: Describe a case of mandibular replacement with a customized titanium prosthesis after ameloblastoma excision. Case presentation: A case is presented of a female 44-year-old patient who presented a radiographic finding during pulporadicular treatment of tooth 37. Facial physical examination found an increase in volume in the left genian region, and intraoral observation detected expansion of the corticals in the lower posterior arch of the same side. Panoramic radiography and computed axial tomography showed a multilocular radiolucid image resembling soap bubbles which extended from the mandibular body to the left condyle. A sample was taken for biopsy, which confirmed the diagnosis of follicular pattern ameloblastoma. Segmental mandibular surgery was performed by cervical approach with a safety margin and exarticulation. The portion removed was replaced with a customized titanium prosthesis. Post-operative control showed a good evolution. Conclusions: Surgery was the basic component of the treatment applied. Surgical resection was followed by reconstruction of the defect with a customized titanium prosthesis, a procedure of great novelty in our environment useful to restore function and esthetic appearance(AU)

Neo Formación Ósea de Rama y Cuerpo Mandibular Tras Uso de Injerto No Vascularizado de Cresta Ilíaca en Re-construcción Inmediata tras Resección de Ameloblastoma Folicular en Paciente de 11 años. Caso Clínico

RESUMEN: El tratamiento "gold standar" para los ameloblastomas mandibulares agresivos, especialmente en aquellas lesiones cuyos márgenes de exceresis superan los 6 cm, es la resección y reconstrucción inmediata con injerto óseo autólogo microvascularizado. Esto se basa en la necesidad de aporte sanguíneo para extensiones amplias de hueso implantado. Es necesario en estos casos una correcta estabilización y fijación del injerto mediante placas de reconstrucción (de titanio), y la ausencia de tejido sometido a radioterapia en la zona a tratar; siendo estos últimos elementos de gran importancia para el éxito quirúrgico. En el caso de pacientes pediátricos, los procesos de oseointegración y reparación ósea se ven beneficiados por el crecimiento fisiológico que conlleva la presencia de multiples factores de crecimiento. El objetivo de este reporte de caso es presentar el tratamiento de un ameloblastoma mandibular en paciente pediátrico tratado mediante resección y reconstrucción con injerto de cresta ilíaca no vascularizado de 10 cm de amplitud. Logrando neoformación ósea 3D del area reconstruida.

ABSTRACT: The gold standard for aggressive mandibular ameloblastomas, with exeresis margins higher than 6 cm, is immediate resection and reconstruction with autologous microvascularized bone graft. A controversy arises because the main reason to endorse this treatment relies on the blood supply for wide extensions of implanted bone. It is necessary in these cases to use a correct stabilization and attachment of the graft employing titanium reconstruction plates and to verify the absence of tissue undergoing radiotherapy. All of the above-mentioned elements are relevant for surgical success. In pediatric patients, the osseointegration and bone repair procedures benefit from physiological growth that entails the presence of multiple growth factors. The aim of this case report is to describe the management of mandibular ameloblastoma diagnosed in a pediatric patient and treated by resection and reconstruction with a non-vascularized 10 cm iliac crest graft thus achieving 3D bone neoformation of the reconstructed area.

Reconstrução mandibular com enxerto livre de crista ilíaca: relato de caso / Mandibular reconstruction with iliac crest free graft: case report

Os defeitos ósseos nos maxilares podem ser causados por patologias como ameloblastoma, carcinoma de células escamosas e sarcomas, bem como, por traumatismos faciais que vão desde acidentes de trânsito a agressões por arma de fogo. As reconstruções de tais defeitos ósseos não deverão apenas devolver a anatomia e contorno da região, mas também, restabelecer a estética e função. A escolha do melhor tipo de enxerto para reconstrução mandibular deverá ser feita de acordo com a característica do defeito e, principalmente, a observação do seu tamanho. O presente trabalho relata o caso clínico de um paciente que procurou o serviço de CTBMF do Hospital da Restauração, queixando-se de deformidade em terço inferior de face após agressão por projétil de arma de fogo (PAF) há, aproximadamente, 2 anos. Ao exame físico apresentava perda de continuidade óssea em região de parassínfise mandibular direita, oclusão pouco funcional e com prometimento funcional. Para o caso foi proposta cirurgia para reconstrução do defeito mandibular com enxerto livre de crista ilíaca. Diante disso, um diagnóstico preciso, planejamento minucioso e boa execução da técnica de reconstrução mandibular com enxerto livre de crista ilíaca proporcionam resultados estéticos satisfatórios, contorno e volume ósseos adequados possibilitando um restabelecimento funcional da área receptora... (AU)

Bone defects in the jaws can be caused by pathologies such as ameloblastoma, squamous cell carcinoma, and sarcomas, as well as facial trauma ranging from traffic accidents to gunshot wounds. Reconstructions of such bone defects should not only restore the anatomy and contour of the region, but also restore aesthetics and function. The choice of the best graft type for mandibular reconstruction should be made according to the characteristic of the defect and, especially, the observation of its size. The present study reports the clinical case of a patient who sought the CTBMF service of the Hospital da Restauração, complaining of deformity in the lower third of the face after aggression by FAP for approximately 2 years. Physical examination showed loss of bone segment in a region of right mandibular paresis, malocclusion and functional impairment. For the case, surgery was proposed to reconstruct the mandibular defect with free iliac crest graft. Therefore, a precise diagnosis, careful planning and good execution of the mandibular reconstruction technique with free iliac crest graft provide satisfactory aesthetic results, adequate bone contour and volume allowing a functional reestablishment of the receiver area... (AU)

Reconstrução microcirúrgica de mandíbula com retalho osteocutâneo de fíbula, com auxílio de modelo 3D, em paciente vítima de trauma: relato de caso / Mandible microsurgical reconstruction with osteocutaneous fibular flap, with the assistance of a 3D model, in a trauma patient: case report

Trata-se de um relato de caso de reconstrução microcirúrgica de mandíbula com retalho osteocutâneo de fíbula em um paciente de 16 anos, vítima de agressão com projétil de arma de fogo e trauma contuso em face, acarretando em fratura cominutiva de mandíbula, com perda de elementos dentários e lesões extensas de partes moles. Após tratamento da fase aguda, optou-se pela reconstrução microcirúrgica com retalho livre de fíbula, devido à extensão do defeito mandibular e possibilidade de reabilitação dentária. O uso de modelos tridimensionais da mandíbula e fíbula foram excepcionalmente úteis para tornar possível o melhor planejamento cirúrgico das áreas de osteotomia, com diminuição do tempo de isquemia do retalho da cirurgia.

This is a case report of the mandible microsurgical reconstruction with osteocutaneous fibular flap in a 16-year-old patient. A victim of an assault with a firearm projectile and blunt trauma to the face, resulting in a comminuted mandible fracture, loss of dental elements, and extensive soft tissue injuries. After treatment of the acute phase, we chose microsurgical reconstruction with a free fibula flap due to the mandibular defect's extension and the possibility of dental rehabilitation. The use of three-dimensional models of the mandible and fibula was exceptionally helpful in making the best surgical planning of the osteotomy areas, decreasing the surgery flap's ischemia time.

Research progress on the reconstruction of mandibular defects in adolescents / 口腔疾病防治

@#Mandibular defects in adolescents are mostly caused by surgical resection of benign and malignant tumors, trauma and jaw inflammation. The reconstruction of mandibular defects in adolescents is challenging. In addition to solving the problem of jaw reconstruction in adults, some clinical factors, including the influence of surgery on the growth of donor and recipient areas, the long-term effects of reconstruction, and the outcome of bone grafts, must also be considered. At present, the main reconstructive methods include autogenous bone grafts and distraction osteogenesis. Autogenous bone grafts are still the gold standard due to their long-term effects. Favorable growth potential after repair was shown in adolescent cases of mandibular reconstruction with fibula flap. Normal occlusion was restored, and a long-term stable effect was achieved in cases of condylar reconstruction with costal cartilage. The safety and clinical effects of distraction osteogenesis have been confirmed, but the long-term effects of large-scale mandibular defects are still uncertain. In addition, other tissue engineering techniques also have good application prospects for the repair and reconstruction of adolescent mandible defects, but more in-depth basic research and more extensive clinical trials should be performed to verify the efficacy.

Clinical application and accuracy analysis of occlusion-guided functional mandibular reconstruction / 中国修复重建外科杂志

Objective: To investigate the influence of the design and application of novel surgical template on the accuracy of reconstructed mandibula and implant position in occlusion-guided functional mandibular reconstruction, so as to provide guidance for clinical treatment. Methods: Between January 2017 and May 2019, 11 patients with segmental mandible defects were treated, including 8 males and 3 females with an average age of 31.8 years (range, 19-45 years). There were 6 cases of ameloblastoma, 3 cases of keratocystic tumor, and 2 cases of ossifying fibroma. According to Urken classification of mandible defects, there were 1 case of CRB, 4 cases of RB, 2 cases of RBS, and 4 cases of SB. According to the occlusion relationship, a novel surgical template with the reconstruction titanium plate screws and implants drill-guided information was designed and manufactured. With the help of the novel surgical template, the "one and a half" fibula reconstruction mode was used for jaw functional reconstruction, and the implant supported denture was finally completed. The postoperative CT at 1 week were collected to analyze the morphology of the preoperative virtual design jaw and postoperative jaw. The coincidence of fibular reconstructed mandible (fibular upper barrel, fibular reconstructed ramus and condyle, and whole mandible) and implant in mandible were calculated. When the coincidence was less than 80%, it was considered that the deviation was obvious. Oral panoramic X-ray film and cone beam CT were examined at 6 months after operation to evaluate the osseointegration before implant repair. Results: None of the 11 flaps had postoperative vascular crisis. One flap occurred necrosis at 1 month after reconstruction combined with 3 implants failed, and had been removed at 6 months after reconstructed surgery; the others had no flap necrosis. One week postoperatively, the coincidence of the fibular upper barrel was 87.55%±3.08%, the whole mandible was 82.68%±5.94%, and the implant in mandible was 88.00%, with significant differences ( t=8.131, P=0.000; t=2.118, P=0.046; Z=4.070, P=0.000) when compared to 80%, respectively. The fibular reconstructed ramus and condyle was 77.82%±3.54%, with no significant difference ( t=-2.042, P=0.068) when compared to 80%. Six months postoperatively, oral panoramic X-ray film and cone beam CT showed that all 22 implants achieved osseointegration and the palatal mucosa transplantation was performed, then finally completed the denture rehabilitation at 6-9 months after operation. All patients were satisfied with their postoperative appearance. Conclusion: The novel surgical template can guarantee the accuracy of functional mandible reconstruction guided by occlusal guidance, and ultimately achieve the beautiful contour of jaw and occlusal function reconstruction, and improve the patient's life quality.

Finite element analysis of different fixation methods for mandibular defects reconstructing with fibula flaps / 中国组织工程研究

BACKGROUND: Segmental defect of mandible is often caused by tumor, trauma and other reasons. Simultaneous mandibular defect by vascularized fibular flap is the most important repair method at present. It is not only useful for the reconstruction with titanium plates, but also useful for small titanium plates for fixation. Clinical retrospective studies have shown that there is no significant difference in postoperative complication rate between patients with the two fixation methods, but relevant biomechanics studies are still lacking at present. OBJECTIVE: The three-dimensional finite element analysis was used to analyze the stress distribution and stability on mandibular segmental defects simulated fibular flaps grafted with reconstruction plates and miniplates fixation. METHODS: A healthy adult male with complete dentition was selected for CT scan and data were input into the computer to reconstruct the mandible and dentition model. Three types of 3D models were built for mandibular defects dependent on Jewer’s classification, including models H (loss of lateral mandible, mandibular angle, ascending branch of mandible, and condyles), L (loss of unilateral mandible) and C (loss of bilateral mandible chin). Mechanical distribution features and stability of fixation with reconstruction plates and miniplates were comparatively studied after fibular repair of mandibular segmental defects. RESULTS AND CONCLUSION: (1) The stress graphs showed that stress was mostly higher in surrounding areas of normal mandibles such as condyle, condylar neck, mandibular angle, molar and titanium screws. In particular, the stress was highest near mandibular angles. (2) For type-H defect, the great stress was generated near the mandibular angles when mandible was reconstructed with reconstruction plate, and the stress value was 185 MPa. The stress values approximately ranged from 117 to 135 MPa on type-H and type-L defects with miniplates. The maximum stress of fibula block was less than 30.4 MPa, and the maximum stress of titanium nail was 56.2 MPa. (3) The relative displacements approximately varied between 15 µm and 18 µm on the fracture sides after repair with type-H and type-L defects with miniplates and reconstruction plates. Almost no relative displacement was generated on the fracture sides after type-C mandibular defects. (4) Both titanium reconstruction plates and titanium miniplates could meet biomechanical requirements for fibular repair of H, C, and L defects.

Glandular odontogenic cyst: report of an unusual case in the posterior mandible / Cisto odontogênico glandular: relato de um caso incomum na região posterior de mandíbula

ABSTRACT The glandular odontogenic cyst (GOC) is an uncommon developmental cyst that presents glandular differentiation and has potential for recurrence. Clinically, it is asymptomatic and it has slow growing. This report proposes to describe a clinical case of GOC diagnosed at the Service of Pathological Anatomy of a university in the northeast of Brazil, in the posterior region of the mandible, which was treated with mandibular resection and bone graft with iliac crest. One may conclude that clinical, microscopic and radiographic parameters were crucial tools for treatment choice.

RESUMEN El quiste odontogénico glandular (QOG) es un quiste del desarrollo poco frecuente que presenta diferenciación glandular y es propenso a la recurrencia. Clinicamente, es asintomático y de crecimiento lento. El presente trabajo tiene como objetivo describir un caso clinico de QOG diagnosticado en la región posterior de la mandíbula en un paciente masculino de 36 anos de edad, atendido en el servicio de Anatomia Patológica de una universidad en el nordeste de Brasil. Se decidió tratarlo por resección mandibular e injerto óseo de la cresta ilíaca. La conclusión a que podemos llegar es que los parâmetros clínicos, microscópicos y radiográficos fueran herramientas esencialespara la elección del tratamiento.

RESUMO O cisto odontogênico glandular (COG) é um cisto de desenvolvimento incomum que apresenta diferenciação glandular e tem potencial de recidiva. Clinicamente, é assintomático e de crescimento lento. Este relato propõe-se a descrever um caso clínico de COG diagnosticado em região posterior de mandíbula em um paciente do gênero masculino, 36 anos de idade, atendido no Serviço de Anatomia Patológica de uma universidade no nordeste do Brasil. Como tratamento, optou-se por ressecção mandibular e enxerto ósseo da crista ilíaca. Conclui-se que os parâmetros clínicos, microscópicos e radiográficos foram ferramentas essenciais na escolha do tratamento realizado.

Odontoma composto em adulto e sua complexidade de tratamento: relato de caso clínico / Compound odontoma in adult and its treatment complexity: clinical case report

Introdução: Odontoma é o tumor odontogênico mais frequente e é diagnosticado durante as primeiras décadas de vida, devido ao atraso na erupção de um dente ou por meio de exame radiográfico de rotina. As características radiográficas e microscópicas são úteis para sua classificação em complexo ou composto. Odontomas em pacientes adultos são incomuns e podem ser complexos de tratar. Objetivo: O objetivo deste trabalho foi relatar a complexidade de tratamento de um odontoma composto em paciente adulto. Material e Método: o presente artigo é do tipo relato de caso. Resultados: Paciente do sexo feminino, 32 anos, compareceu ao cirurgião-dentista para avaliação clínica de rotina. Durante o exame clínico foi observada a ausência do dente 43, exames radiográficos demonstraram lesão mista, bem delimitada, com estruturas semelhantes a dentículos, localizada na região anterior de mandíbula do lado direito, entre as raízes dos dentes 42 e 44, promovendo deslocamento do dente 43 para a base da mandíbula. Devido à localização da lesão e seus efeitos no dente 43, a paciente foi submetida à ressecção da lesão sob anestesia geral. Foi realizada osteotomia na tábua óssea vestibular da mandíbula, remoção de múltiplas estruturas semelhantes a dentes, instalação de placa de reconstrução mandibular sistema 2.4 com cinco parafusos do mesmo sistema e enxerto ósseo com biomaterial aloplástico. O dente 13 foi extraído. As radiografias de controle pós-operatório evidenciaram bom posicionamento do material. O controle pós-operatório indica que a paciente encontra-se bem e sem ausência de sinais de recidiva ou complicações cirúrgicas. Conclusão: O diagnóstico tardio de odontomas associado ao deslocamento dentário ocasionado pelo tumor podem tornar o seu tratamento mais complexo.

Introduction: The most common odontogenic tumor is Odontoma, and is diagnosed during the first decades of life, due to a delayed eruption of a tooth, or through routine radiographic examination. From the radiographic and microscopic characteristics is classified into complex or compound. Odontomas in adult patients are uncommon and can have a complex treatment. Aim: The aim of this study was to report the complexity of treating a compound odontoma in an adult patient. Material and Methods: the present research is a case report. Results: A 32-year-old female patient attended the dental surgeon for routine evaluation. During the clinical examination, the absence of tooth 43 was observed, image exams revealed a well-defined mixed lesion consisting of denticles, located in the anterior region of the right mandible, between the roots of the teeth 42 and 44, the lesion promoted displacement of tooth 43. Due to the location and its effects on tooth 43, the patient underwent resection of the lesion under general anesthesia. Surgery proceeded with buccal plate osteotomy, removal of multiple tooth-like structures, installation of mandibular reconstruction plates 2.4 with five screws and bone graft with alloplastic biomaterial. Tooth 13 was extracted. Postoperative control radiographs showed good positioning of the material. Postoperative control show that patient does not have recurrence signal or complications due to surgery. Conclusion: Late diagnosis of odontomas associated with tooth displacement caused by the tumor may make its treatment more complex.

Intraosseous mucoepidermoid carcinoma

Mucoepidermoid carcinoma (MEC) is a common malignant tumor composed of mucinous cells, clear cells and squamoid tumor cells. It is usually localized on the salivary glands, however can very rarely be intraosseous. This tumor affects women more than men and is more common in the mandible. In this report, we present a case of a 45-year-old woman with a painless intraoral mass for 10 years which was repeatedly misdiagnosed, evolving into an extensive lesion. After an appropriate approach, she was diagnosed with MEC of the mandible and submitted to a left hemimandibulectomy accompanied by microsurgical reconstruction with excellent results.

Study Of Distribution Of Various Accessory Foramina In 100 Human Mandibles Of South India

Introduction: Any unnamed opening is termed as Accessory foramen. Mandible being the strongest bone of theskull is pervaded by many accessory foramina other than mandibular and mental foramen. In the present studyaccessory mandibular, mental, retromolar and lingual foramina are distinguished and clinical implications arediscussed. The presence of such foramina if not identified during clinical practice may cause complications.Hence our study is done to find out the incidence and distribution of various accessory foramina of mandibleamong South Indians.Materials and Methods: The study was done on 100 adult dry human mandibles of South Indian origin obtainedfrom first MBBS students. The location and distribution of various accessory foramina were carefully observed,noted and tabulated.Results: Accessory foramen was found in 93% of mandibles. Accessory lingual foramen was found in 93 mandibles,with supraspinous foramen in 84%, accessory mandibular foramen in 34%, accessory mental foramen in 12%and retromolar foramen in 6%.Conclusion: Presence of accessory foramina may cause failure of anaesthesia during inferior alveolar nerveblock and haemorrhage during mandibular reconstruction surgeries owing to the neurovascular structurespassing through these accessory foramina. The clinicians should be aware about the presence of such accessoryforamina during the procedures.

The effect of fixation plate use on bone healing during the reconstruction of mandibular defects

OBJECTIVES: This study sought to compare efficiency results between the use of a customized implant (CI) and a reconstruction plate (RP) in mandibular defect reconstruction in an animal model. MATERIALS AND METHODS: Fifteen rabbits underwent surgery to create a defect in the right side of the mandible and were randomly divided into two groups. For reconstruction of the mandibular defect, the RP group (n=5) received five-hole mini-plates without bone grafting and the CI group (n=10) received fabricated CIs based on the cone-beam computed tomography (CBCT) data taken preoperatively. The CI group was further divided into two subgroups depending on the time of CBCT performance preoperatively, as follows: a six-week CI (6WCI) group (n=5) and a one-week CI (1WCI) group (n=5). Daily food intake amount (DFIA) was measured to assess the recovery rate. Radiographic images were acquired to evaluate screw quantity. CBCT and histological examination were performed in the CI subgroup after sacrifice. RESULTS: The 1WCI group showed the highest value in peak average recovery rate and the fastest average recovery rate. In terms of reaching a 50% recovery rate, the 1WCI group required the least number of days as compared with the other groups (2.6±1.3 days), while the RP group required the least number of days to reach an 80% recovery rate (7.8±2.2 days). The 1WCI group showed the highest percentage of intact screws (94.3%). New bone formation was observed in the CI group during histological examination. CONCLUSION: Rabbits with mandibular defects treated with CI showed higher and faster recovery rates and more favorable screw status as compared with those treated with a five-hole mini-plate without bone graft.