Search results for "Foramen"
showing 10 items of 93 documents
Cone-beam computed tomography analysis of root and canal morphology of mandibular premolars in a Spanish population
2014
Purpose: This study aimed to investigate the clinical anatomy of lower premolar roots in a Spanish population by using cone-beam computed tomography (CBCT), correlating findings with patient gender and tooth type. Materials and Methods: Using 70 CBCT images, we evaluated 126 healthy, untreated, well-developed lower premolars. The number and morphology of roots and root canals, and the foramina number were assessed. Results for gender and tooth type were compared using the chi-squared and ANOVA tests. Results: The average length of teeth and roots was significantly higher in men (p=0.00). All 126 premolars had a single root. One canal was found in 83.3% of the premolars, with no gender or to…
Root Canal Morphology and Configuration of 179 Maxillary First Molars by Means of Micro-computed Tomography: An Ex Vivo Study
2015
Introduction The objective of this study was to propose a root canal configuration description method and to investigate the root canal system morphology of the maxillary first molar by means of micro-computed tomographic imaging. Methods The root canal configuration, foramina, and accessory canal frequency of 179 maxillary first molars were investigated by means of micro-computed tomographic imaging and 3-dimensional software imaging. The root canal configuration and main foramina number are described from coronal to apical with a 4-digit system. Results The most frequent root canal configurations were 1-1-1/1 (45.8%), 2-2-2/2 (25.1%) and 2-2-1/1 (10.1%) in mesiobuccal roots and 1-1-1/1 in…
Le supra-occipital des Cétacés et des Rongeurs fouisseurs. Une convergence morphologique induite par le pôle post-céphalique ?
2000
A comparative study of the cranial morphologies of cetaceans and of rodents that use their incisors for burrowing brings out morphological convergences concerning the supra-occipital bone. These phyletically very remote groups are both subject to the same mechanical constraint, viz. the need for the spinal column to be aligned with the anteroposterior axis of the skull. This constraint, which is related to swimming in cetaceans and burrowing in rodents, entails three major points of convergence: 1) a clearly backward facing foramen magnum; 2) a shortened or even greatly shortened neck, sometimes with cervical vertebrae fused together; and 3) an uprighted or even forward tilted supra-occipit…
Intracranial Pressure and Mass Displacements of the Intracranial Contents
1976
The brain is completely surrounded by the bony skull and its closely adherent, tough, dural inner lining. This converts the enclosed space into a watertight chamber with the exception of the small, basally situated foramen magnum. In adults, these factors combine to prevent the skull from expanding. Consequently, the intracranial volume cannot fluctuate. In addition, the intracranial contents — blood, brain, and spinal fluid — are essentially noncompressible.
The Role of Endoscopy in the Treatment of Acute Traumatic Anterior Epidural Hematoma of the Cervical Spine: Case Report
1997
OBJECTIVE AND IMPORTANCE: Epidural hematoma (EDH) of the spine represents an uncommon neurosurgical disorder that sometimes requ;res emergent surgical decompressive therapy. Traumatic EDH of the cervical spine is exceedingly rare. The hematoma is usually located dorsally in the epidural space. We present one case of acute EDH located ventrally in the cervical spine. Special emphasis is placed on the role of spinal endoscopy in surgical treatment. CLINICAL PRESENTATION: After a fall from a tree, a 69-year-old man with rapidly increasing tetraparesis was referred to our institution. Plain films of the cervical spine revealed nothing abnormal. The results of computed tomography were highly sus…
Arterial O2-Partial Pressure at Positve Endexpiratory Pressure in Hyperoxia for Verification of Patent Foramen Ovale?
1990
As a rule, during anaesthesia a time dependent increase in pulmonary shunting occurs even in states of normal lung function. Therefore positive end-expiratory pressure ventilation (PEEP) is often used to decrease intrapulmonary right/left shunting (RL shunt) and thus to increase arterial O2 partial pressure (paO2) without increasing the inspiratory oxygen fraction.
Two new species of the genusBatropetes(Tetrapoda, Lepospondyli) from the Central European Rotliegend (basal Permian) in Germany
2015
ABSTRACTTwo new species of Batropetes are described from the Lower Rotliegend of the Saar-Nahe Basin in western Germany. Batropetes palatinus, sp. nov., is characterized by a narrow, anteriorly elongated prefrontal, a slender postfrontal without an anterolateral process, a trapezoid postorbital, and a large quadrate in exterior view. Batropetes appelensis, sp. nov., is characterized by a high angular, ‘Z’-shaped angular-dentary suture, no indentation between stem and plate of interclavicle, and scapulocoracoid without ossified coracoid. The genus Batropetes is characterized by an average length of almost 8 cm, a short trunk with 17 or 19 presacrals depending on the species, large orbit with…
Prevalence of anatomic variations of the atlas vertebra
2018
Abstract BACKGROUND CONTEXT The retrotransverse foramen (RTF), arcuate foramen (AF), unclosed transverse foramen (UTF) and posterior atlas arch defects (PAAD) are anatomic variations of the atlas vertebra that surgeons must be aware of before spine surgery is performed. PURPOSE To analyze the prevalence of the AF, RTF, UTF, and PAAD. STUDY DESIGN Ex-vivo anatomical study. PATIENT SAMPLE Two hundred eighteen atlas vertebrae obtained from 100 Caucasian subjects and 118 sub-Saharan African subjects (48 Sotho subjects, 35 Xhosa subjects and 35 Zulu subjects). METHODS We studied 218 atlas vertebrae from skeletons of the Raymond A. Dart Collection in order to analyze the prevalence of AF, RTF, UT…
Changes in dimension of neurovascular canals in the mandible and maxilla: A radiographic finding in patients diagnosed with MRONJ.
2017
Background The aim of this retrospective study was to compare the morphological features of neurovascular canals and foramina of patients with medication-related osteonecrosis of the jaws (MRONJ) and healthy individuals by using cone beam computed tomography (CBCT). Material and Methods The CBCT images of 58 patients under bisphosphonate therapy diagnosed with MRONJ and age gender- matched controls were retrospectively evaluated. The diameter of mandibular and nasopalatine canal and mandibular, mental and lingual foramina were measured on several sections of CBCT. The value of mental index (MI) and panoramic mandibular index (PMI) were also assessed. Results The mean value of diametric meas…
Atlases with Arcuate Foramen Present Cortical Bone Thickening That May Contribute to Lower Fracture Risk.
2018
To date, no information about the cortical bone microstructural properties in atlas vertebrae with arcuate foramen has been reported. As a result, we aimed to test in an experimental model if there is a cortical bone thickening in an atlas vertebra which has an arcuate foramen that may play a protective role against bone fracture.We analyzed by means of micro-computed tomography the cortical bone thickness, the cortical volume, and the medullary volume (SkyScan 1172 Bruker micro-CT NV, Kontich, Belgium) in cadaveric dry atlas vertebrae with arcuate foramen and without arcuate foramen. We also reviewed a case series of 31 posterior atlas arch fractures to correlate the possible presence in t…