107 research outputs found

    Patologie della base-cranica anteriore con Piezosurgery

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    .PIEZOSURGERY\uae Stato dell\u2019arte e prospettive Chirurgia Cranio Facciale Neurochirurgi

    Basic and advanced endoscopic sinus surgery course: open and endoscopic cadaver dissection techniques and live surgery.

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    This course originates from the close collaboration experienced and established over many years between the three professionals most involved in the surgical treatment of lesions of the anterior skull base. We believe, and the results have proved us right, that the achievement of the best treatment in such complex anatomical regions can be born only from an accurate preoperative study, the realization of several surgical procedures and the care of every detail during the post-operative period carried out in a close collaboration among Otolaryngologists, Maxilo-Facial surgeons and Neurosurgeons. The relatively recent introduction of endoscopic surgery and the huge expansion of the latter has further expanded the possibilities of collaboration. On the other hand those who want to approach to this type of pathologies necessarily have to know not only the techniques and possibilities of endoscopy but also the open techniques which are essential to face certain situations or clinical manifestations. The experience of many years of shared work between two surgical university schools with great traditions such as Modena and Verona besides a personal friendship established over time has enabled us both to joint the three specialties and to create a group that is inspired by the same principles

    A comparative in vivo evaluation of bioactive glasses and bioactive glass-based composites for bone tissue repair

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    In this work a set of novel materials for bone tissue regeneration have been tested in vivo in an animal model. In fact, despite many studies have been devoted to amorphous 45S5 Bioglass®, there is lack in the literature of works aimed to study the in vivo performance of heat-treated – and thus partially crystallized – 45S5. As widely reported, crystallization limits the bioactivity of 45S5 and is the main reason that prevents a broader use of this material. Thus, in the present work, a recently developed bioactive glass (BG_Ca/Mix) is tested, since previous investigations demonstrated that BG_Ca/Mix is particularly promising by virtue of both its high bioactivity and lower tendency to crystallize with respect to 45S5. BG_Ca/Mix sintered powders and two composites, which contain BG_Ca/Mix and an increasing percentage (20 wt% or 70 wt%) of hydroxyapatite (HA), were considered. As a term of comparison, 45S5 sintered powders were also studied. The samples were implanted in rabbits' femurs and harvested after 8 weeks. The histological analysis demonstrated that BG_Ca/Mix has an osteoconductive ability slightly higher than that of 45S5 glass-ceramics, followed by that of the composites, which may represent the starting point for obtaining systems with degradation rate tailored for a given clinical application. Moreover, the 45S5 samples were locally cracked, probably because of a non-uniform dissolution in the physiological environment. On the contrary such cracks, which could lead to implant instability and unsuitable mechanical performance, were not observed in BG_Ca/Mix

    Microsurgical reconstruction of the mandible in a patient with evans syndrome: a case report and review of the literature

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    In this report, we describe the first successful case of microvascular free tissue transfer in a patient with Evans Syndrome (ES), a rare form of idiopathic thrombocytopenic purpura (ITP) and associated autoimmune hemolytic anemia (AIHA). Microvascular surgery in the setting of ES is likely to have higher complication rates because of the increased risk of postoperative bleeding and free flap thrombosis. The case presented here opens up to the feasibility of microvascular reconstruction of patients with coagulation disorders like ES. Every effort should be made to control for hemolytic, thrombocytopenic, and thrombophilic states associated with ES. In the absence of evidence-based treatment guidelines for ES, personalized treatment protocols with high-dose corticosteroids, immunoglobulin, and postoperative anticoagulation regimen are highly recommended

    PRELIMINARY FINDINGS OF A POTENZIATED PIEZOSURGERGICAL DEVICE AT THE RABBIT SKULL

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    The number of available ultrasonic osteotomes has remarkably increased. In vitro and in vivo studies have revealed differences between conventional osteotomes, such as rotating or sawing devices, and ultrasound-supported osteotomes (Piezosurgery®) regarding the micromorphology and roughness values of osteotomized bone surfaces. Objective: the present study compares the micro-morphologies and roughness values of osteotomized bone surfaces after the application of rotating and sawing devices, Piezosurgery Medical® and Piezosurgery Medical New Generation Powerful Handpiece. Methods: Fresh, standard-sized bony samples were taken from a rabbit skull using the following osteotomes: rotating and sawing devices, Piezosurgery Medical® and a Piezosurgery Medical New Generation Powerful Handpiece. The required duration of time for each osteotomy was recorded. Micromorphologies and roughness values to characterize the bone surfaces following the different osteotomy methods were described. The prepared surfaces were examined via light microscopy, environmental surface electron microscopy (ESEM), transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM) and atomic force microscopy. The selective cutting of mineralized tissues while preserving adjacent soft tissue (dura mater and nervous tissue) was studied. Bone necrosis of the osteotomy sites and the vitality of the osteocytes near the sectional plane were investigated, as well as the proportion of apoptosis or cell degeneration. Results and Conclusions: The potential positive effects on bone healing and reossification associated with different devices were evaluated and the comparative analysis among the different devices used was performed, in order to determine the best osteotomes to be employed during cranio-facial surgery

    Sol-gel derived bioactive glasses with low tendency to crystallize: synthesis, post-sintering bioactivity and possible application for the production of porous scaffolds.

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    A new sol-gel (SG) method is proposed to produce special bioactive glasses (BG_Ca family) characterized by a low tendency to devitrify. These formulations, derived from 45S5 Bioglass®, are characterized by a high content of CaO (45.6 mol%) and by a partial or complete substitution of sodium oxide with potassium oxide (total amount of alkaline oxides: 4.6 mol%), which increases the crystallization temperature up to 900°C. In this way, it is possible to produce them by SG preserving their amorphous nature, in spite of the calcination at 850°C. The sintering behavior of the obtained SG powders is thoroughly investigated and the properties of the sintered bodies are compared to those of the melt-derived (M) counterparts. Furthermore, the SG glass powders are successfully used to produce scaffolds by means of a modified replication technique based on the combined use of polyurethane sponges and polyethylene particles. Finally, in the view of a potential application for bone tissue engineering, the cytotoxicity of the produced materials is evaluated in vitro

    Ameloblastic fibroma in a 6-year old child:case report.

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    Ameloblastic fibroma (AF) is defined in WHO classification as a ''neoplasm composed of proliferating odontogenic epithelium embedded in a cellular ectomesenchymal tissue that resembles dental papilla, and with varying degrees of inductive change and dental hard tissue formation''. AF is a rather uncommon tumor, accounting for only 2.5% of all odontogenic tumors. AF is a true mixed tumor, in which the epithelial and ectomesenchymal elements are neoplastic. AF raises at any age, ranging from 6 months to 42 years (mean 14.6 to 15.5 years); it does not show sex predilection. The lesion occurs in nearly 70% of cases in posterior areas of the mandible. Patients exhibit swelling of the jaw; pain is not usually described. Authors present a clinical and surgical management of an early onset of a large mandibular ameloblastic fibroma in a 6-year-old girsl

    Reconstructive Surgery after Oncocological Treatment (2024) In R. Nocini, G. Molteni, S.A. Mocella, D. Bertossi (Eds.), The Nasal Setpoplasty (pp.211-225). Piccin, Padova, Italy.

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    Removal of components of the nasal septum for oncological causes is a frequent intervention. Reconstruction of the septum mainly consists in rebuilding the L-strut, which is the key to the structural support. The L-strut defect might be partial (more frequent) or total. External and internal lining have also to be rebuilt when missing. Lining reconstruction is fundamental to nourish the graft and to avoid post-operative complications. Considerations regarding immediate or delayed procedures have to be evaluated. There are many different types of grafts that can be harvested (septal cartilage and bone, costal cartilage and bone, auricular cartilage, cranial bone, radial bone). The graft used to rebuild the neo-septum has to be chosen according to the extent of the defect and to the surgeon’s experience

    From Osteoclast Differentiation to Osteonecrosis of the Jaw: Molecular and Clinical Insights

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    Bone physiology relies on the delicate balance between resorption and formation of its tissue. Bone resorption depends on a process called osteoclastogenesis in which bone-resorbing cells, i.e., osteoclasts, are produced by the differentiation of more undifferentiated progenitors and precursors. This process is governed by two main factors, monocyte colony-stimulating factor (M-CSF) and receptor activator of NFκB ligand (RANKL). While the former exerts a proliferating effect on progenitors/precursors, the latter triggers a differentiation effect on more mature cells of the same lineage. Bone homeostasis requires a perfect space–time coordination of the involved signals. When osteoclastogenesis is poorly balanced with the differentiation of the bone forming counterparts, i.e., osteoblasts, physiological bone remodelling can turn into a pathological state, causing the systematic disruption of bone tissue which results in osteopenia or osteolysis. Examples of these conditions are represented by osteoporosis, Paget’s disease, bone metastasis, and multiple myeloma. Therefore, drugs targeting osteoclastogenesis, such as bisphosphonates and an anti-RANKL monoclonal antibody, have been developed and are currently used in the treatment of such diseases. Despite their demonstrated therapeutic efficacy, these agents are unfortunately not devoid of side effects. In this regard, a condition called osteonecrosis of the jaw (ONJ) has been recently correlated with anti-resorptive therapy. In this review we will address the involvement of osteoclasts and osteoclast-related factors in the pathogenesis of ONJ. It is to be hoped that a better understanding of the biological mechanisms underlying bone remodelling will help in the design a medical therapeutic approach for ONJ as an alternative to surgical procedures.Bone physiology relies on the delicate balance between resorption and formation of its tissue. Bone resorption depends on a process called osteoclastogenesis in which bone-resorbing cells, i.e., osteoclasts, are produced by the differentiation of more undifferentiated progenitors and precursors. This process is governed by two main factors, monocyte colony-stimulating factor (M-CSF) and receptor activator of NFκB ligand (RANKL). While the former exerts a proliferating effect on progenitors/precursors, the latter triggers a differentiation effect on more mature cells of the same lineage. Bone homeostasis requires a perfect space–time coordination of the involved signals. When osteoclastogenesis is poorly balanced with the differentiation of the bone forming counterparts, i.e., osteoblasts, physiological bone remodelling can turn into a pathological state, causing the systematic disruption of bone tissue which results in osteopenia or osteolysis. Examples of these conditions are represented by osteoporosis, Paget’s disease, bone metastasis, and multiple myeloma. Therefore, drugs targeting osteoclastogenesis, such as bisphosphonates and an anti-RANKL monoclonal antibody, have been developed and are currently used in the treatment of such diseases. Despite their demonstrated therapeutic efficacy, these agents are unfortunately not devoid of side effects. In this regard, a condition called osteonecrosis of the jaw (ONJ) has been recently correlated with anti-resorptive therapy. In this review we will address the involvement of osteoclasts and osteoclast-related factors in the pathogenesis of ONJ. It is to be hoped that a better understanding of the biological mechanisms underlying bone remodelling will help in the design a medical therapeutic approach for ONJ as an alternative to surgical procedures
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