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1.
Am J Forensic Med Pathol ; 39(4): 354-356, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29727315

RESUMEN

Lethal donkey attacks have very rarely been described. The case of a 65-year-old man who was found deceased on a country road with 2 domestic donkeys nearby is, therefore, reported. Examination of the body revealed contusions and lacerations of the face and scalp, a comminuted fracture of the left maxilla, comminuted fracturing of the right radius and ulna and of the left anterior superior iliac spine, a flail chest, and pulmonary contusions. In addition, there were bite marks on the left thigh, right buttock, right axilla/upper arm, and left cheek which corresponded to the dental arcades of the donkeys. Death had resulted from blunt chest trauma due to an attack by 1 or 2 donkeys. Deaths and serious injuries are much more commonly caused by horses; however, this case shows that even domesticated donkeys may also rarely be capable of inflicting significant trauma and so should be approached with circumspection.


Asunto(s)
Agresión , Mordeduras y Picaduras/patología , Equidae , Traumatismo Múltiple/patología , Anciano , Animales , Mordeduras y Picaduras/etiología , Resultado Fatal , Fracturas Conminutas/etiología , Fracturas Conminutas/patología , Humanos , Masculino , Traumatismo Múltiple/etiología
2.
Clin Oral Implants Res ; 20(3): 306-12, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19397643

RESUMEN

INTRODUCTION: Endosseus implants can provide a reliable anchorage during orthodontic treatment. The midpalatal structures around the sutura palatina mediana (SPM) are of special interest due to increasing placement of orthodontic implants in this area. Knowledge about the osseous conditions at this site is necessary to predict the expected degree of implant osseointegration. METHODS: The upper jaws of 10 human cadavers, aged 15-20 years, were decalcified, and cross-sectional specimens were obtained from four anterior-to-posterior palatal regions for histomorphometric analysis. The analyses focused on the amount of bone and the width of the SPM to determine the anatomical requirements for reliable insertion of palatal implants. RESULTS: Bone density [bone-volume (BV)/ tissue-volume (TV)] in all measured areas was 40-60%. The maximum density was measured at the level of the first premolars (54.9+/-5.9%) and the least values (44.2+/-9.6%) were measured at the level of the interconnecting line of the canines. The mean width of the SPM varies from 1.2 to 0.3 mm in different sections of the palate. In the median sagittal plane, the mean values of bone height to nasal cavity reached >5 mm as far as the level distal of the second premolars. Bone height 2 mm paramedian to the SPM decreased consistently from anterior (4.3+/-0.9 mm) to posterior (2.5+/-0.8 mm). CONCLUSIONS: Our results indicate that the amount and quality of bone along the anterior palatal midline in 15-to-20-year olds is sufficient for orthodontic implantation. Even implantation posterior to the recommended first premolar level, at which orthodontic implants are most often placed, may be suitable. There are some limitations, however, due to small number of samples and variations of anatomical structures.


Asunto(s)
Suturas Craneales/anatomía & histología , Implantación Dental Endoósea/normas , Métodos de Anclaje en Ortodoncia/normas , Hueso Paladar/anatomía & histología , Adolescente , Anatomía Transversal , Humanos , Adulto Joven
3.
Clin Oral Implants Res ; 19(6): 590-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18422983

RESUMEN

OBJECTIVES: The aims of this study were to evaluate the rate of bone formation and osseointegration after topical gene delivery with a liposomal vector system carrying bone morphogenetic protein (BMP)-2 cDNA in combination with a collagen carrier and autologous bone as a carrier in freshly created peri-implant bone defects. MATERIALS AND METHODS: Eight domestic pigs received nine calvariae defects each (10 x 7 mm). A dental implant was inserted into the centre of each defect. In the test groups, the remaining space was filled with the liposomal vector/BMP-2 complex combined with a collagen carrier (n=18) or an autologous bone graft (n=18). Control groups were collagen only (n=18) and autologous bone graft only (n=18). RESULTS: There was a significant difference in mineralisation rate in the BMP-2/bone graft (29.9%+/- 4.8 and 68.3%+/- 7.2) and bone graft only (22.6%+/- 2.6 and 49.4%+/- 13.9) groups after 7 and 28 days. Mineralisation values were also significantly higher in the BMP-2/collagen group (21.2%+/- 16.2 and 53.1%+/- 12.5) compared with the collagen-only group (8.2%+/- 7 and 41%+/- 8.1) in two different regions after 28 days. Also the bone-to-implant contact was significantly increased in the BMP-2/bone graft group after 28 days and in the BMP-2/collagen group after 7 and 28 days compared with their control groups. CONCLUSIONS: The results of this study show a significantly positive effect of liposomal vector/BMP-2 on bone regeneration and osseointegration in bony circumferential peri-implant defects.


Asunto(s)
Proteínas Morfogenéticas Óseas/administración & dosificación , Regeneración Ósea/fisiología , Implantes Dentales , Hueso Frontal/metabolismo , Terapia Genética/métodos , Oseointegración/fisiología , Factor de Crecimiento Transformador beta/administración & dosificación , Animales , Proteína Morfogenética Ósea 2 , Proteínas Morfogenéticas Óseas/genética , Regeneración Ósea/genética , Trasplante Óseo/métodos , Trasplante Óseo/fisiología , Colágeno , ADN Complementario , Sistemas de Liberación de Medicamentos , Femenino , Regulación de la Expresión Génica/fisiología , Técnicas de Transferencia de Gen , Vectores Genéticos/administración & dosificación , Liposomas , Oseointegración/genética , Osteogénesis/genética , Osteogénesis/fisiología , Plásmidos/administración & dosificación , Estadísticas no Paramétricas , Sus scrofa , Factor de Crecimiento Transformador beta/genética , Trasplante Autólogo/métodos , Trasplante Autólogo/fisiología
4.
J Craniomaxillofac Surg ; 40(4): 310-20, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21723141

RESUMEN

Due to donor side morbidity and the absence of osteogenic properties in bone substitutes, there is a growing need for an alternative to traditional bone grafting within the scope of tissue engineering. This animal study was conducted to compare the in vivo osteogenic potential of adipose-derived (AD), periosteum-derived (PD) and bone marrow-derived (BM) mesenchymal stem/progenitor cells (MSC). Autologous mesenchymal stem/progenitor cells of named tissue origin were induced into osteogenic differentiation following in vitro cell expansion. Ex vivo cultivated cells were seeded on a collagen scaffold and subsequently added to freshly created monocortical calvarial bone defects in 21 domestic pigs. Pure collagen scaffold served as a control defect. The animals were sacrificed at specific time points and de novo bone formation was quantitatively analyzed by histomorphometry. Bone volume/total defect volume (BV/TV) and the mineralization rate of newly formed bone were compared among the groups. In the early stages of wound healing, up to 30 days, the test defects did not show better bone regeneration than those in the control defect, but the bone healing process in the test defects was accelerated in the later stage compared to those in the control defect. All the test defects showed complete osseous healing after 90 days compared to those in the control defect. During the observation period, no significant differences in BV/TV and mineralization of newly formed bone among the test defects were observed. Irrespective of the tissue sources of MSC, the speed and pattern of osseous healing after cell transplantations into monocortical bone defects were comparable. Our results indicate that the efficiency of autologous AD-MSC, PD-MSC and BM-MSC transplantation following ex vivo cell expansion is not significantly different for the guided regeneration of bone defects.


Asunto(s)
Regeneración Ósea/fisiología , Regeneración Tisular Dirigida/métodos , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/clasificación , Fosfatasa Alcalina/análisis , Animales , Enfermedades Óseas/cirugía , Células de la Médula Ósea/clasificación , Proteína Morfogenética Ósea 2/análisis , Proteína Morfogenética Ósea 4/análisis , Calcificación Fisiológica/fisiología , Técnicas de Cultivo de Célula , Diferenciación Celular/fisiología , Colágeno , Subunidad alfa 1 del Factor de Unión al Sitio Principal/análisis , Femenino , Hueso Frontal/cirugía , Procesamiento de Imagen Asistido por Computador/métodos , Células Madre Mesenquimatosas/fisiología , Microrradiografía/métodos , Osteoblastos/fisiología , Osteocalcina/análisis , Osteogénesis/fisiología , Periostio/citología , Grasa Subcutánea/citología , Sus scrofa , Porcinos , Factores de Tiempo , Andamios del Tejido , Trasplante Autólogo
5.
J Biomed Mater Res A ; 93(4): 1510-8, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20014295

RESUMEN

Reconstruction of bone defects with autogenous, autoclaved bone grafts has already been described but does have one major insuperable problem-the loss of the ostoinductive potential of the graft. In this study, we investigated if autogenous, autoclaved grafts in combination with tissue engineered bone can overcome this problem. An en-bloc resection was done in the mandible of eight pigs. The grafts were autoclaved and filled with autogenous, osseogen differentiated bone marrow cells and compared with four animals without bone marrow cells. After 120 days, the specimens were qualitatively and quantitatively evaluated by means of microradiography and light microscopy. Within the experimental group, osseous remodeling was detected in all cases and new bone formation was visible. Quantitative assessment of the osseous bridging of the osteotomy sites was significantly higher in the test group in comparison with the control group (p = 0.03). The histological evaluation by means of an osseous integration of the grafts revealed a statistically significant difference between both groups as well (p = 0.01). The results of this study indicate that the method investigated hereby represents a further possibility in the therapy of bony defects, such as those arising as a result of tumor operations.


Asunto(s)
Células de la Médula Ósea/patología , Trasplante Óseo/métodos , Mandíbula/patología , Ingeniería de Tejidos/métodos , Animales , Células de la Médula Ósea/metabolismo , Trasplante de Médula Ósea/métodos , Regeneración Ósea , Sustitutos de Huesos/química , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular , Osteotomía/métodos , Proyectos Piloto , Esterilización , Porcinos
6.
Artículo en Inglés | MEDLINE | ID: mdl-18206408

RESUMEN

OBJECTIVE: Different bone substitute materials are used to manage the challenge of local bone loss subsequent to craniofacial reconstructive surgery. In this animal study we examined the de novo bone formation in bone defects after insertion of Puros Allograft of human origin or Navigraft of bovine origin, and compared the regenerative potential of each material to that of autogenous bone. STUDY DESIGN: Using the adult domestic pig as the animal model, we created identical bone defects in the frontal skull and filled them with the different test materials using random assignment. A defined number of defects remained unfilled to serve as control. We performed microradiographic, histologic, and polychromatic fluorescence labeling evaluations of the bone specimens at 1, 8, and 12 weeks after the procedure. RESULTS: Both of the materials that we tested allowed for complete bony consolidation of the defects by the end of the test period. After 12 weeks, the microradiographically measured mineralization rate was 5% to 10% lower than the mineralization rate of autogenous bone grafts. CONCLUSION: Both Puros Allograft and Navigraft met the clinical requirements for bone substitutes, promoting predictable regeneration of the bony defects.


Asunto(s)
Regeneración Ósea/fisiología , Resorción Ósea/terapia , Sustitutos de Huesos/uso terapéutico , Animales , Trasplante Óseo/métodos , Bovinos , Hueso Frontal/diagnóstico por imagen , Hueso Frontal/cirugía , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Microrradiografía , Porcinos , Factores de Tiempo
7.
Artículo en Inglés | MEDLINE | ID: mdl-17618141

RESUMEN

OBJECTIVE: Sinus augmentation is a common approach for patients with severe alveolar ridge atrophy. However, autogenous bone sometimes results in donor site complications. Bone substitutes with platelet-rich plasma (PRP) promote early bone formation with autogenous bone. Use of PRP on autogenous bone and a bovine bone substitute were investigated in this split-mouth animal study. STUDY DESIGN: Premolars were extracted from minipigs. Each animal received sinus augmentation using a lateral approach with simultaneous insertion of 3 implants in each site. Groups were randomized using autogenous bone alone and combined with PRP or a bovine hydroxyapatite alone in combination with PRP. RESULTS: Microradiographic findings in the autogenous group did not show significantly different rates by using autogenous bone alone or combined with PRP. Using the bovine hydroxyapatite as augmentation material only at 8 weeks, a nonsignificant effect in the PRP group could be seen. At all other observation periods, no significant influence was observed. CONCLUSION: No significant influence of PRP was found.


Asunto(s)
Sustitutos de Huesos/uso terapéutico , Trasplante Óseo/métodos , Seno Maxilar/cirugía , Plasma Rico en Plaquetas/diagnóstico por imagen , Animales , Materiales Biocompatibles/uso terapéutico , Trasplante Óseo/diagnóstico por imagen , Bovinos , Implantación Dental Endoósea/métodos , Durapatita/uso terapéutico , Seno Maxilar/diagnóstico por imagen , Microrradiografía/métodos , Modelos Animales , Porcinos , Porcinos Enanos , Factores de Tiempo
8.
Artículo en Inglés | MEDLINE | ID: mdl-16122653

RESUMEN

BACKGROUND: Autologous bone is the standard material used for augmentations in oral-maxillofacial surgery. Depending on the origin of the graft, subsequent bone resorption may vary. STUDY DESIGN: This prospective study evaluated 57 patients receiving 2-stage sinus floor augmentations. Monocortical samples were taken at the site of bone harvesting, including the posterior (n = 28) and anterior pelvic (n = 15) and retromolar (n = 14) regions. At second-stage surgery, 6 months after the implant insertion, bone cores were harvested at the site of implant placement. All samples were analyzed by microradiography. RESULTS: Mean retromolar mineralization was 68.7% +/- 8.75%; 35.1% +/- 7.6% in the anterior and 30.7% +/- 9.5% in the posterior iliac crest. Areas augmented with grafts originating from the retromolar region showed a significant decrease to 53.0% +/- 5.15% (P = .001). A stable mineralization of 36.1% +/- 7.59% was found in sites where bone grafts from the anterior pelvic crest were used. Grafts from the posterior pelvis showed a slight increase to 34.5% +/- 6.5%. CONCLUSION: This prospective clinical study demonstrates the differences in mineralization depending on the origin of autogenous bone. Even after 6 months, these values could still be correlated to the transplants origin.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Trasplante Óseo/métodos , Trasplante Óseo/fisiología , Recolección de Tejidos y Órganos , Densidad Ósea , Calcificación Fisiológica , Implantación Dental Endoósea , Femenino , Humanos , Ilion/cirugía , Masculino , Mandíbula/cirugía , Seno Maxilar/cirugía , Microrradiografía , Persona de Mediana Edad , Procedimientos Quirúrgicos Preprotésicos Orales/métodos , Estudios Prospectivos , Estadísticas no Paramétricas , Trasplante Autólogo/métodos
9.
J Oral Pathol Med ; 31(8): 450-7, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12220351

RESUMEN

BACKGROUND: Deranged expression and function of the E-cadherin/beta-catenin (E-cad/beta-cat) complex and the epidermal growth factor receptor (EGFR) have been implicated in the development and progression of carcinomas. METHODS: To estimate the role of these molecules in oral cancer, we investigated 75 primary oral squamous cell carcinomas (OSCCs) with adjacent normal and/or dysplastic mucosa, 30 paired metastases and 12 recurrences by immunohistochemistry. RESULTS: All three molecules were constitutionally expressed in the basal/parabasal layers of tumour adjacent 'normal' epithelium, in contrast to a significant increase of EGFR and heterogeneous expression of E-cad/beta-cat in dysplasia. In OSCCs, over-expression of EGFR correlated significantly with lower tumour grade and poor prognosis, loss of E-cad was a significant marker for shortened survival, reduced beta-cat staining was a predictive marker for lymph node metastasis. CONCLUSIONS: There is a perturbance in intercellular adhesion molecules and EGFR expression/function in oral cancer with major clinical impact. E-cad and beta-cat seem to inhibit EGFR to enhance the progression of OSCCs.


Asunto(s)
Cadherinas/genética , Carcinoma de Células Escamosas/genética , Proteínas del Citoesqueleto/genética , Receptores ErbB/genética , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias de la Boca/genética , Transactivadores/genética , Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Estudios de Cohortes , Progresión de la Enfermedad , Epitelio/metabolismo , Epitelio/patología , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Modelos Lineales , Metástasis Linfática/genética , Metástasis Linfática/patología , Masculino , Análisis por Apareamiento , Mucosa Bucal/metabolismo , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Recurrencia Local de Neoplasia/genética , Pronóstico , Modelos de Riesgos Proporcionales , Estadística como Asunto , Tasa de Supervivencia , beta Catenina
10.
J Pathol ; 198(3): 343-51, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12375267

RESUMEN

The aim of this study was to define whether or not the impaired expression of CD44, E-cadherin (E-cad), and beta-catenin (beta-cat) correlates with the clinical evolution and prognosis of oral cancer. Ninety-three primary oral squamous cell carcinomas (OSCCs) with tumour-adjacent normal and/or dysplastic mucosa, 30 associated metastases, and 12 recurrences were immunostained for CD44s, -v3, -v4, -v5, -v6, -v7, -v9, E-cad, and beta-cat. In non-neoplastic epithelium, all molecules investigated were constitutively expressed in the basal layers. In the majority of dysplasias, immunoreactivity for all adhesion molecules was increased, but there was restricted loss for CD44s, E-cad, and beta-cat in a few cases. In carcinomas, a striking accumulation of CD44s, v3, v4, v9 and a loss of E-cad/beta-cat were observed at the invasive tumour front. In metastases and recurrences, besides a loss of CD44s, v4, v7, and E-cad, a significant increase of v9 was recorded, whereas CD44v5 and v6 remained unchanged. Clinically, reduced expression of CD44v3, E-cad, and changes of CD44v9 phenotype within the primary tumours correlated significantly with poor prognosis; decreased beta-cat expression was a predictive marker for nodal metastases. These findings indicate that there is some perturbed expression of adhesion molecules during the stepwise course of oral carcinogenesis and tumour progression. Distinct phenotypic alterations project poor prognosis, while others predict metastasis. Some of these restricted molecular changes may serve as potential targets for future antibody-based tumour therapy.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Moléculas de Adhesión Celular/metabolismo , Transformación Celular Neoplásica/metabolismo , Neoplasias de la Boca/metabolismo , Cadherinas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Proteínas del Citoesqueleto/metabolismo , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Receptores de Hialuranos/metabolismo , Metástasis Linfática , Masculino , Neoplasias de la Boca/patología , Proteínas de Neoplasias/metabolismo , Lesiones Precancerosas/metabolismo , Pronóstico , Tasa de Supervivencia , Transactivadores/metabolismo , beta Catenina
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