Search results for "Plate"
showing 10 items of 1689 documents
LES VARIATIONS DU NIVEAU MARIN SUR LE BASSIN DE PARIS AU BATHONIEN-CALLOVIEN. IMPACTS SUR LES COMMUNAUTÉS BENTHIQUES ET SUR L'ÉVOLUTION DES ORNITHELL…
1992
The study deals with the biological impacts of sea-Ievel changes on evolution of a Jurassic benthic fossil group (Ornithellida, Brachiopoda). The different time and scale at which the shifts in marine environments occur leads to the recognition of three interacting dynamic systems: environmental, communities, populations dynamics. The analysis is thus divided into a three steps hierarchy: sequence stratigraphy, analysis of the diversity of brachiopod assemblages, and analysis of morphological variations within omithellid populations. Sequence stratigraphy of the Dogger marly and carbonate successions in the Paris basin provides accurate correlations of depositional environments from shallow…
Radiological implications of crestal and subcrestal implant placement in posterior areas. A cone-beam computed tomography study
2020
Background Subcrestal implant placement has been suggested as a method that could contribute to maintain the periimplant soft and hard tissues in comparison with crestal placement. The objective of this study was to investigate the relationship between implant placement at different depths in the alveolar bone and (a) the thickness of the buccal bone plate (BBP); and (b) crestal cortical bone thickness, based on the use of cone-beam computed tomography (CBCT). Material and Methods A cross-sectional study was performed, analyzing CBCT scans from the database of the Oral Surgery Unit of the University of Valencia. Individuals with single missing teeth in posterior sectors were included. Two t…
Soft-tissue cone-beam computed tomography (ST-CBCT) technique for the analysis of skeletal, dental and periodontal effects of orthopedic rapid maxill…
2018
Background Orthopedic rapid maxillary expansion (RME) is a common treatment of choice for managing transverse deficiency of the maxilla. This approach may have desired and undesired skeletal, dental and periodontal effects that may be assessed clinically or through imaging techniques. This study aims to investigate the dental, skeletal and periodontal effects of orthopedic RME using the soft-tissue cone-beam computed tomography (CBCT) technique. Material and Methods The sample consisted of 10 patients (5males and 5 females) aged between 10 and 14 years (mean age: 12.5 years) treated with Hyrax orthopedic device. CBCT scans set for the registration of soft tissue (ST-CBCT) were taken from ea…
Osteosynthese am proximalen Humerus mittels winkelstabiler Platte oder Doppelplatte: eine vergleichende biomechanische Untersuchung / Angle-fixed pla…
2008
Internal fixation of fractures of the proximal humerus needs a high stability of fixation to avoid secondary loss of fixation. This is especially important in osteoporotic bone. In an experimental study, the biomechanical properties of the angle-fixed Philos plate (internal fixator) and a double-plate osteosynthesis using two one-third tubular plates were assessed. The fracture model was an unstable three-part fracture (AO type B2). Eight pairs of human cadaveric humeri were submitted to axial load and torque. In the first part of the study, it was assessed to which degree the original stiffness of the humeri could be restored after the osteotomy by the osteosynthesis procedure. Subsequentl…
Photoelastic analysis of conventional and locking system for treatment of mandibular angle fractures with a single plate
2021
Made available in DSpace on 2021-06-25T10:28:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Background: This photoelastic analysis evaluated stress distribution in different osteosynthesis systems, conventional and locking, used for treatment of mandibular angle fractures with a single plate. Material and Methods: Angle fractures were simulated in mandibles made of photoelastic resin. Following Champy’s method, plate osteosynthesis was performed. The samples were divided into five groups: Group 1, non-fractured mandible; Group 2, two screws were installed in each segment using a conventional system; Group 3, two screws were installed in each segment using a locking system; …
Bone remodeling in malunited fractures in children. Is it reliable?
1997
Fracture malunion is not a rare phenomenon in children due to the frequent use of closed reduction treatments. In this article, the processes of bone remodeling in cases of angular and rotational deformities, overriding of bone fragments, and overgrowth are addressed. Critical analyses of the mechanisms to correct these deformities, function of the physis and periosteum, and other related factors are given. The acceptable deformities for complete remodeling to be successful vary at different ages and locations.
Retrograde nailing versus locking plate osteosynthesis of proximal humeral fractures: a biomechanical study
2011
Background In locking plate osteosynthesis of proximal humeral fractures, secondary varus malalignment is a specific complication. Retron nails (Tantum AG, Neumunster, Germany), among others, have been designed to improve medial support of the calcar humeri. The aim of our biomechanical study was to examine whether Retron nails provide increased stiffness for axial loads and adequate stiffness for torsional loads when compared with Philos plates (Synthes AG, Umkirch, Germany). Materials and methods Twenty-two fresh-frozen paired humeri were collected. After potting the specimens, intact bones were exposed to sinusoidal axial (10-120 N) and torsional (±2.5 Nm) loading for 8 cycles to calcula…
Intramedullary nailing vs. palmar locked plating for unstable dorsally comminuted distal radius fractures: A biomechanical study
2010
Abstract Background The purpose of this study was to compare the stability of a 2.4 mm palmar locking compression plate and a new intramedullary nail-plate-hybrid Targon DR for dorsally comminuted distal radius fractures. Methods An extraarticular 10 mm dorsally open wedge osteotomy was created in 8 pairs of fresh frozen human radii to simulate an AO–A3-fracture. The fractures were stabilized using one of the fixation methods. The specimens were loaded axially with 200 N and dorsal-excentrically with 80 N. 2000 cycles of dynamic loading and axial loading-to-failure were performed. Findings Axial loading revealed that intramedullary osteosynthesis (Targon DR: 369 N/mm) was significantly ( p …
Content of blood cell components, inflammatory cytokines and growth factors in autologous platelet-rich plasma obtained by various methods.
2022
BACKGROUND The evaluation of the efficacy of platelet-rich plasma (PRP) in clinical practice yields conflicting results and raises numerous controversies. This may be due to different concentrations of biologically active components in PRP obtained with the use of different methods of gravity separation. AIM To compare the content, repeatability and correlations between biologically active components in PRP obtained with four different commercial systems. METHODS From a whole blood sample of each of 12 healthy male volunteers, 4 PRP samples were prepared using 4 different commercial kits [Arthrex Autologous Conditioned Plasma (ACP), Mini GPS III, Xerthra, Dr. PRP] in accordance with the ins…
Placchetta a rilievo con testa maschile
2019
Studio di una lamina di osso con una testa maschile del Museo Archeologico Regionale "A. Salinas" di Palermo. A study of a little bone plate with a male head of the Regional Archaeological Museum "A. Salinas" in Palermo.