oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Implant-retained craniofacial prostheses for facial defects
Federspil, Philipp A.
GMS Current Topics in Otorhinolaryngology, Head and Neck Surgery , 2009,
Abstract: Craniofacial prostheses, also known as epistheses, are artificial substitutes for facial defects. The breakthrough for rehabilitation of facial defects with implant-retained prostheses came with the development of the modern silicones and bone anchorage. Following the discovery of the osseointegration of titanium in the 1950s, dental implants have been made of titanium in the 1960s. In 1977, the first extraoral titanium implant was inserted in a patient. Later, various solitary extraoral implant systems were developed. Grouped implant systems have also been developed which may be placed more reliably in areas with low bone presentation, as in the nasal and orbital region, or the ideally pneumatised mastoid process. Today, even large facial prostheses may be securely retained. The classical atraumatic surgical technique has remained an unchanged prerequisite for successful implantation of any system. This review outlines the basic principles of osseointegration as well as the main features of extraoral implantology.
Prevention of Cutaneous Tissue Contracture During Removal of Craniofacial Implant Superstructures for CT and MRI Studies  [PDF]
Maureen Sullivan,Rachael Rossitto,David Casey
Journal of Oral & Maxillofacial Research , 2010,
Abstract: Objectives: Head and neck cancer patients who have lost facial parts following surgical intervention frequently require craniofacial implant retained facial prostheses for restoration. Many craniofacial implant patients require computed tomography and magnetic resonance imaging scans as part of their long-term follow-up care. Consequently removal of implant superstructures and peri-abutment tissue management is required for those studies. The purpose of the present paper was to describe a method for eliminating cranial imaging artifacts in patients with craniofacial implants.Material and Methods: Three patients wearing extraoral implant retained facial prostheses needing either computed tomography or magnetic resonance imaging studies were discussed. Peri-implant soft tissues contracture after removal of percutaneous craniofacial implant abutments during computed tomography and magnetic resonance imaging studies was prevented using a method proposed by authors. The procedure involves temporary removal of the supra-implant components prior to imaging and filling of the tissue openings with polyvinyl siloxane dental impression material.Results: Immediately after filling of the tissue openings with polyvinyl siloxane dental impression material patients were sent for the imaging studies, and were asked to return for removal of the silicone plugs and reconnection of all superstructure hardware after imaging procedures were complete. The silicone plugs were easily removed with a dental explorer. The percutaneous abutments were immediately replaced and screwed into the implants which were at the bone level.Conclusions: Presented herein method eliminates the source of artifacts and prevents contracture of percutaneous tissues upon removal of the implant abutments during imaging.
The Role of Imaging in Craniofacial Anomalies
P. Alipour,J. Jalal Shokouki
Iranian Journal of Radiology , 2008,
Abstract: It is important to know craniofacial anatomy in infancy for early detection of craniofacial anomalies, to help the surgeon's decision ,for repair and increase the patients, quality of life .In this regard, imaging has the major role in preoperative diagnostic maping and post operative follow up repair."nWe are going to show the normal craniofacial anatomy appearances in infancy in order to detect early craniofacial anomaly and syndromatic craniosynostosis with plain skull X-ray and CT scan reconstruction imaging.
Craniofacial features in Goldenhar syndrome  [cached]
Vinay C,Reddy R,Uloopi K,Madhuri V
Journal of the Indian Society of Pedodontics and Preventive Dentistry , 2009,
Abstract: Goldenhar syndrome also known as oculo-auriculo-vertebral syndrome was first reported by Dr Maurice Goldenhar in 1952. It is a rare disease entity characterized by craniofacial anomalies such as hypoplasia of the mandible and malar bones, microtia, and vertebral anomalies. The etiology of this disease still remains unclear and occurs as sporadic. This report presents goldenhar syndrome in a 12-year-old male patient.
Craniofacial surgery for craniometaphyseal dysplasia
Ahmad F,Mahapatra A,Mahajan H
Neurology India , 2006,
Abstract: Craniometaphyseal dysplasia (CMD) is a rare congenital bone dysplasia with abnormal bony overgrowth leading to characteristic facial features and cranial nerve compression. We present a 10-year-old child with bony swelling at the nasal root since birth along with decreased hearing in both ears. She had normal developmental milestones and intelligence. On examination, she had bossing of forehead with very broad nasal root, short septum, hypertelorism and epicanthic folds. CT scan with 3D reconstruction revealed grossly thickened calvarium and hyperostosis and sclerosis of the cranial base. As the major concern of the parents was cosmetic, craniofacial reconstruction was performed with good cosmetic outcome
Craniofacial ontogeny in Centrosaurus apertus  [PDF]
Joseph A. Frederickson,Allison R. Tumarkin-Deratzian
PeerJ , 2015, DOI: 10.7717/peerj.252
Abstract: Centrosaurus apertus, a large bodied ceratopsid from the Late Cretaceous of North America, is one of the most common fossils recovered from the Belly River Group. This fossil record shows a wide diversity in morphology and size, with specimens ranging from putative juveniles to fully-grown individuals. The goal of this study was to reconstruct the ontogenetic changes that occur in the craniofacial skeleton of C. apertus through a quantitative cladistic analysis. Forty-seven cranial specimens were independently coded in separate data matrices for 80 hypothetical multistate growth characters and 130 hypothetical binary growth characters. Both analyses yielded the max-limit of 100,000 most parsimonious saved trees and the strict consensus collapsed into large polytomies. In order to reduce conflict resulting from missing data, fragmentary individuals were removed and the analyses were rerun. Among both the complete and the reduced data sets the multistate analyses recovered a shorter tree with a higher consistency index (CI) than the additive binary data sets. The arrangement within the trees shows a progression of specimens with a recurved nasal horn in the least mature individuals, followed by specimens with straight nasal horns in relatively more mature individuals, and finally specimens with procurved nasal horns in the most mature individuals. The most mature individuals are further characterized by the reduction of the cranial horn ornamentations in late growth stages, a trait that similarly occurs in the growth of other dinosaurs. Bone textural changes were found to be sufficient proxies for relative maturity in individuals that have not reached adult size. Additionally, frill length is congruent with relative maturity status and makes an acceptable proxy for ontogenetic status, especially in smaller individuals. In adult-sized individuals, the fusion of the epiparietals and episquamosals and the orientation of the nasal horn are the best indicators of relative maturity. This study recovers no clear evidence for sexually specific display structures or size dimorphism in C. apertus.
Biomaterials for craniofacial reconstruction
Neumann, Andreas,Kevenhoerster, Kevin
GMS Current Topics in Otorhinolaryngology, Head and Neck Surgery , 2009,
Abstract: Biomaterials for reconstruction of bony defects of the skull comprise of osteosynthetic materials applied after osteotomies or traumatic fractures and materials to fill bony defects which result from malformation, trauma or tumor resections. Other applications concern functional augmentations for dental implants or aesthetic augmentations in the facial region.For ostheosynthesis, mini- and microplates made from titanium alloys provide major advantages concerning biocompatibility, stability and individual fitting to the implant bed. The necessity of removing asymptomatic plates and screws after fracture healing is still a controversial issue. Risks and costs of secondary surgery for removal face a low rate of complications (due to corrosion products) when the material remains in situ. Resorbable osteosynthesis systems have similar mechanical stability and are especially useful in the growing skull.The huge variety of biomaterials for the reconstruction of bony defects makes it difficult to decide which material is adequate for which indication and for which site. The optimal biomaterial that meets every requirement (e.g. biocompatibility, stability, intraoperative fitting, product safety, low costs etc.) does not exist. The different material types are (autogenic) bone and many alloplastics such as metals (mainly titanium), ceramics, plastics and composites. Future developments aim to improve physical and biological properties, especially regarding surface interactions. To date, tissue engineered bone is far from routine clinical application.
Neuroembryology and functional anatomy of craniofacial clefts  [cached]
Ewings Ember,Carstens Michael
Indian Journal of Plastic Surgery , 2009,
Abstract: The master plan of all vertebrate embryos is based on neuroanatomy. The embryo can be anatomically divided into discrete units called neuromeres so that each carries unique genetic traits. Embryonic neural crest cells arising from each neuromere induce development of nerves and concomitant arteries and support the development of specific craniofacial tissues or developmental fields. Fields are assembled upon each other in a programmed spatiotemporal order. Abnormalities in one field can affect the shape and position of developing adjacent fields. Craniofacial clefts represent states of excess or deficiency within and between specific developmental fields. The neuromeric organization of the embryo is the common denominator for understanding normal anatomy and pathology of the head and neck. Tessier′s observational cleft classification system can be redefined using neuroanatomic embryology. Reassessment of Tessier′s empiric observations demonstrates a more rational rearrangement of cleft zones, particularly near the midline. Neuromeric theory is also a means to understand and define other common craniofacial problems. Cleft palate, encephaloceles, craniosynostosis and cranial base defects may be analyzed in the same way.
An experimental model for the study of craniofacial deformities
Costa, André de Mendon?a;Kobayashi, Gerson Shigeru;Bueno, Daniela Franco;Martins, Marília Trierveiler;Ferreira, Marcus de Castro;Passos-Bueno, Maria Rita;Alonso, Nivaldo;
Acta Cirurgica Brasileira , 2010, DOI: 10.1590/S0102-86502010000300008
Abstract: purpose: to develop an experimental surgical model in rats for the study of craniofacial abnormalities. methods: full thickness calvarial defects with 10x10-mm and 5x8-mm dimensions were created in 40 male nis wistar rats, body weight ranging from 320 to 420 g. the animals were equally divided into two groups. the periosteum was removed and dura mater was left intact. animals were killed at 8 and 16 weeks postoperatively and cranial tissue samples were taken from the defects for histological analysis. results: cranial defects remained open even after 16 weeks postoperatively. conclusion: the experimental model with 5x8-mm defects in the parietal region with the removal of the periosteum and maintenance of the integrity of the dura mater are critical and might be used for the study of cranial bone defects in craniofacial abnormalities.
Morphometry of biliar tree  [PDF]
J. Deli?,A. Savkovi?,E. Isakovi?
Medicinski Glasnik , 2006,
Abstract: Anatomic variations of extrahepatic bile ducts may be problematic during surgical procedures. The aim of this study was to evaluate frequency of anatomic variations of the biliary tree. Morphometric characteristics of the biliary tree segments and angles between them are described in this paper. The investigation was carried out on 120 cadaveric human livers. The main methods were anatomic macro-disection and morphometry. Very high variability of length of the biliary tree segments was noticed: ductus hepaticus communis (0-39,75 mm), ductus cysticus (6,25-46,25 mm) and ductus choledochus (66,75-120,50 mm).
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.