Ricinus communis biocompatibility histological study in the nose of Cebus apella monkeys

Lesões do tecido ósseo podem ser causadas por fatores congênitos e adquiridos e resultar em deformidade nasal com repercussão estética e funcional. O tratamento cirúrgico desses casos requer reconstruções complexas e frequentemente o uso de biomateriais. O poliuretano derivado do óleo da mamona apresenta uma fórmula com aspectos favoráveis de processabilidade, flexibilidade de formulação, ausência de emissão de vapores tóxicos e baixo custo. Entretanto, a despeito dos resultados favoráveis, estudos referentes ao uso do polímero de mamona, avaliando a reação tecidual no dorso nasal, ainda não foram realizados. OBJETIVO: O objetivo deste estudo consiste em avaliar histologicamente a biocompatibilidade do implante do polímero de mamona no dorso nasal. FORMA DE ESTUDO: Experimental. MATERIAL E MÉTODO: Foram utilizados quatro macacos-pregos da espécie Cebus apella. Um defeito ósseo foi realizado no osso nasal em todos os animais e colocado um implante de polímero de mamona. A eutanásia foi realizada com 270 dias de pós-operatório, e as amostras foram submetidas a estudo histológico. RESULTADOS: Na análise histológica não foi observada a presença de granuloma de corpo estranho ou células fagocitárias. Progressiva formação óssea e maturação foram observadas. CONCLUSÃO: Os resultados macroscópicos e microscópicos mostraram que o implante de polímero de mamona foi biocompatível.

Use of Titanium Mesh for Reconstruction of Extensive Defects in Fronto-orbito-ethmoidal Fracture

Traumatic injuries treatment of the fronto-naso-orbito-ethmoidal region has been one of the most challenging treatments within maxillofacial surgery, particularly of extensive orbital defects, very common in this type of pathologic condition. A 48-year-old man involved in a car collision presented an extensive bilateral fracture of the orbit medial wall, nasal bones, the nasal septum, and the frontal anterior table. The clinical and tomographic findings concluded the diagnosis of a maxilla and fronto-naso-orbito-ethmoidal fracture. Among the variety of biomaterials, the titanium mesh was elected because of the extension and magnitude of the bone defect, obtaining this way esthetic and functional results with better prognosis.

Use of 4 Immediately Loaded Zygomatic Fixtures for Retreatment of Atrophic Edentulous Maxilla After Complications of Maxillary Reconstruction

This article reports the 20-month clinical outcome of the use of 4 zygomatic implants with immediate occlusal loading and reverse planning for the retreatment of atrophic edentulous maxilla after failed rehabilitation with autogenous bone graft reconstruction and maxillary implants. The intraoral clinical examination revealed mispositioned and loosened implants underneath a maxillary complete denture. The panoramic radiograph showed 6 maxillary implants. One implant was displaced into the right maxillary sinus, and the implant anchored in the region of tooth 21 was fractured. The other implants presented peri-implant bone loss. The implants anchored in the regions of teeth 21 to 23 and 11 to 13 were first removed. After 2 months, the reverse planning started with placement of 4 zygomatic fixtures, removal of the implants migrated into the sinus cavity and anchored in the region of tooth 17, and installation of a fixed denture. After 20 months of follow-up, no painful symptoms, peri-implant inflammation or infection, implant instability, or bone resorption was observed. The outcomes of this case confirm that the zygoma can offer a predictable anchorage and support function for a fixed denture in severely resorbed maxillae.

Maxillary Bone Defect Reconstruction Using Porous Polyethylene Implants

Purpose: The aim of this study was to evaluate the bone repair process in the maxillary sinus in monkeys treated with high-density porous polyethylene (Medpor)Methods: Four capuchin monkeys (Cebus apella) were submitted to bilateral horizontal osteotomies in the anterior wall of the maxillary sinus and divided into 2 groups: control group, left side with no implants, and porous polyethylene group, right side with Medpor. After a period of 145 days after implant placement, the maxillae were removed for histologic and histometric analyses.Results: Bone repair in osteotomized areas took place by connective tissue in 58.5% and 58.7% in the control group and the porous polyethylene group, respectively. In the contact surface with Medpor, bone repair occurred in 41.3%.Conclusions: Medpor was not reabsorbed within the period of this study and allowed bone repair surrounding it. The porous polyethylene constitutes a feasible alternative for bone defect reconstruction.

Patients' Satisfaction After Surgical Facial Reconstruction or After Rehabilitation With Maxillofacial Prosthesis

The matching of the aesthetic, functional, and psychosocial results of a facial deformity may produce devastating effects in its carriers, especially if the lesion is extensive or the treatment is aggressive. Because of this, the objective of the present article was to evaluate patient's satisfaction rating after surgical facial reconstruction or rehabilitation with oral and maxillofacial prosthesis, by means of reviewing the literature.

Most Frequent Tumors in Maxillofacial Area Rehabilitated Through Surgical Reconstruction and Prostheses

Cancer is regarded as the abnormal cellular multiplication; it is not controlled by the organism; and its cells present a differentiated DNA. Initially, the disease does not show clinical signs, but it can be diagnosed by laboratorial examinations. When tumors are present in the maxillofacial area, they can entail the loss of these area organs, which become responsible for the carrier's social environment exclusion. This paper aimed at showing, through a literature review, the cancers that more commonly happen in the face and the possibilities of regenerating in the patient mutilated through surgical reconstruction and prostheses.

Reconstruction of Skull Defects: Currently Available Materials

The restoration and recovery of a compromised skull continues to be a challenge to craniofacial surgeons and neurosurgeons. Different operative techniques and implant materials are being used to reconstruct the rigid framework of the skull. However, no currently available materials satisfy all of these criteria. According to this premise, the aim of this study was to report on the currently available materials for the reconstruction of the cranial vault and to describe their main characteristics, advantages, and disadvantages. Although the use of the materials discussed in this study is clearly positive for the reconstruction of skull defects and cranioplasties, there is a need for more complex studies and research into developing these materials to achieve all the ideal prerequisites stipulated by the scientific community and to evaluate their properties and aesthetic and functional results in the long term.

Management of Orbital Reconstruction

One of the concerns after a major trauma to the orbit is to be rebuilt. This can be achieved with care in management of orbital reconstruction, techniques, types of materials, and osseointegrated implants; it allows satisfactory aesthetic recuperation and well-being, whereas psychological therapy allows for patients' re-insertion in social and family environment to make them feel happier and safer.

Immediate reconstruction of frontal sinus fractures: review of 26 cases

Purpose: the purpose of this study was to evaluate complications occurring after immediate reconstruction of severe frontal sinus fractures, including cases where the fracture was not limited to the anterior wall and also involved the posterior wall and/or sinus floor.Patients and Methods: the records of twenty-six patients presently undergoing follow-up for frontal sinus fracture reconstruction were reviewed. Information regarding demographics, fracture characteristics and causes, associated facial fractures, use of grafts or implants, type of fixation used, nasofrontal duct management, use of antibiotics, and complications were noted. Patients were asked to return for clinical and radiographic follow-up to access late complications.Results: the average age of patients with frontal fractures was 29.1 years and 92.3% were male. Mean follow-up was 3.6 years. The most common causes of fracture were motor vehicle accidents and physical aggression. All patients presented with comminuted and dislocated anterior wall fractures, 34.6% presented with posterior wall fractures, and 46% had sinus floor fractures. Complications occurred in 7 patients (26.92%) and included pneumoencephalus, frontal cutaneous fistula, frontal bone irregularity, and sinusitis.Conclusions: Frontal sinus reconstruction is a good procedure for immediate fracture treatment if there is not excessive comminution, dislocation, or instability of the posterior wall and if the frontonasal duct area is intact or can be repaired. Most complications result from incorrect indication for reconstruction. (C) 2004 American Association of Oral and Maxillofacial Surgeons.

Tests of one Brazilian facial reconstruction method using three soft tissue depth sets and familiar assessors

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

3D reconstruction and scanning electron microscopy of salivary glands of the millipede Rhinocricus padbergi (Verhoef, 1938) (Diplopoda: Spirobolida)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Resistance to compression of weakened roots subjected to different root reconstruction protocols

Objective: This study evaluated, in vitro, the fracture resistance of human non-vital teeth restored with different reconstruction protocols. Material and methods: Forty human anterior roots of similar shape and dimensions were assigned to four groups (n=10), according to the root reconstruction protocol: Group I (control): non-weakened roots with glass fiber post; Group II: roots with composite resin by incremental technique and glass fiber post; Group III: roots with accessory glass fiber posts and glass fiber post; and Group IV: roots with anatomic glass fiber post technique. Following post cementation and core reconstruction, the roots were embedded in chemically activated acrylic resin and submitted to fracture resistance testing, with a compressive load at an angle of 45 degrees in relation to the long axis of the root at a speed of 0.5 mm/min until fracture. All data were statistically analyzed with bilateral Dunnett's test (alpha=0.05). Results: Group I presented higher mean values of fracture resistance when compared with the three experimental groups, which, in turn, presented similar resistance to fracture among each other. None of the techniques of root reconstruction with intraradicular posts improved root strength, and the incremental technique was suggested as being the most recommendable, since the type of fracture that occurred allowed the remaining dental structure to be repaired. Conclusion: The results of this in vitro study suggest that the healthy remaining radicular dentin is more important to increase fracture resistance than the root reconstruction protocol.

Reconstruction of interacting dark energy models from parametrizations

Models with interacting dark energy can alleviate the cosmic coincidence problem by allowing dark matter and dark energy to evolve in a similar fashion. At a fundamental level, these models are specified by choosing a functional form for the scalar potential and for the interaction term. However, in order to compare to observational data it is usually more convenient to use parametrizations of the dark energy equation of state and the evolution of the dark matter energy density. Once the relevant parameters are fitted, it is important to obtain the shape of the fundamental functions. In this paper I show how to reconstruct the scalar potential and the scalar interaction with dark matter from general parametrizations. I give a few examples and show that it is possible for the effective equation of state for the scalar field to cross the phantom barrier when interactions are allowed. I analyze the uncertainties in the reconstructed potential arising from foreseen errors in the estimation of fit parameters and point out that a Yukawa-like linear interaction results from a simple parametrization of the coupling.

Measurement of B(B)over-bar angular correlations based on secondary vertex reconstruction at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Performance of tau-lepton reconstruction and identification in CMS

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)