Search results for "bones"
showing 10 items of 279 documents
Alcohol abusive use increases facial trauma?
2016
Background Trauma is among the main death causes and morbidity in the world and is often related to the use of alcohol and its abuse has reached massive proportions, no matter if the country is developed or not, being considered as public health problem. Since there are very few randomized and prospective studies in literature about the association of facial trauma and the use of alcohol, this study aims to investigate the impact of alcohol use in facial trauma. Material and Methods This was a prospective and cross sectional study, involving facial trauma patients attended at Oral Maxillofacial Surgery Division of a State Hospital. Variables included patient´s profile, trauma etiology, faci…
Modeling the electromechanical impedance technique for the assessment of dental implant stability
2015
We simulated the electromechanical impedance (EMI) technique to assess the stability of dental implants. The technique consists of bonding a piezoelectric transducer to the element to be monitored. When subjected to an electric field, the transducer induces structural excitations which, in turn, affect the transducer's electrical admittance. As the structural vibrations depend on the mechanical impedance of the element, the measurement of the transducer's admittance can be exploited to assess the element's health. In the study presented in this paper, we created a 3D finite element model to mimic a transducer bonded to the abutment of a dental implant placed in a host bone site. We simulate…
Small-sized granules of biphasic bone substitutes support fast implant bed vascularization
2015
The present study investigated the influence of granule size of 2 biphasic bone substitutes (BoneCeramic® 400-700 μm and 500-1000 μm) on the induction of multinucleated giant cells (MNGCs) and implant bed vascularization in a subcutaneous implantation model in rats. Furthermore, degradation mechanisms and particle phagocytosis of both materials were examined by transmission electron microscopy (TEM). Both granule types induced tissue reactions involving primarily mononuclear cells and only small numbers of MNGCs. Higher numbers of MNGCs were detected in the group with small granules starting on day 30, while higher vascularization was observed only at day 10 in this group. TEM analysis reve…
Lrp4, a Novel Receptor for Dickkopf 1 and Sclerostin, Is Expressed by Osteoblasts and Regulates Bone Growth and Turnover In Vivo
2009
Lrp4 is a multifunctional member of the low density lipoprotein-receptor gene family and a modulator of extracellular cell signaling pathways in development. For example, Lrp4 binds Wise, a secreted Wnt modulator and BMP antagonist. Lrp4 shares structural elements within the extracellular ligand binding domain with Lrp5 and Lrp6, two established Wnt co-receptors with important roles in osteogenesis. Sclerostin is a potent osteocyte secreted inhibitor of bone formation that directly binds Lrp5 and Lrp6 and modulates both BMP and Wnt signaling. The anti-osteogenic effect of sclerostin is thought to be mediated mainly by inhibition of Wnt signaling through Lrp5/6 within osteoblasts. Dickkopf1 …
Cdc42 in osterix-expressing cells alters osteoblast behavior and myeloid lineage commitment
2021
Osteoblasts are not only responsible for bone formation. They also support hematopoiesis. This requires responding to cues originating from several signaling pathways, a task performed by Rho GTPases. We therefore examined several transgenic mouse models and used inhibitors of Cdc42 in vitro. Deletion of Cdc42 in vivo using the Osterix promoter suppressed osteoblast function, while its deletion in differentiating osteoblasts using the Collagen-a1(I) promoter decreased osteoblast numbers. In both cases, bone mineral density diminished confirming the importance of Cdc42. Evaluation of hematopoiesis revealed that deletion of Cdc42 using the Osterix, but not the Collagen-a1(I) promoter increase…
Thalassemia (Microkarterocytosis) and Drepanocytosis their Forms and Genetics
1952
SummaryThalassemia, that I propose to call Microkarterocytosis, can be divided into three forms to be distinguished under the names of minima (healthy carriers), minor (Rietti and Greppi's disease), major (Cooley disease).It can be inferred that Thalassemia is a mutation developped in a mediterranean superior paleolitic race that showed also the character high cheek bones.In my researches of 1941-42 I for first showed that thalassemia is a dominant hereditary character with homozigotic letal effect (heterozigotes the healthy carriers, homozigotes Cooley' patients).Heterozigotes throug an increased expression of the morbid gene develop Rietti and Greppi disease, as I inferred in 1949.The res…
Mathematical modeling of fetal limb growth
1989
Using ultrasound measurements of the femur, tibia, humerus, radius (N = 515), and fibula and ulna (N = 385) from normal fetuses between 12 and 40 completed weeks of gestation, growth models were determined for each bone by computer analysis. On the basis of residual analysis, growth of fetal limb bones could best be expressed as a function of tangens hyperbolicus. Growth profiles and growth data are shown with 5th, 10th, 50th, 90th, and 95th percentiles. These results are compared with previous investigations of limb bone measurements.
Foreign Body Giant Cell–Related Encapsulation of a Synthetic Material Three Years After Augmentation
2016
Bone substitute materials of different origin and chemical compositions are frequently used in augmentation procedures to enlarge the local bone amount. However, relatively little data exist on the long-term tissue reactions. The presented case reports for the first time histological and histomorphometrical analyses of a nanocrystaline hydroxyapatite–based bone substitute material implanted in the human sinus cavity after an integration period of 3 years. The extracted biopsy was analyzed histologically and histomorphometrically with focus on the tissue reactions, vascularization, new bone formation, and the induction of a foreign body reaction. A comparably high rate of connective tissue (…
Adherence to Guidelines among Italian Urologists on Imaging Preoperative Staging of Low-Risk Prostate Cancer: Results from the MIRROR (Multicenter It…
2011
Objective. A number of evidence-based guidelines for diagnosis and management of prostate cancer have been published. The aim of this study is to evaluate the adherence of Italian urologists to the guidelines concerning the preoperative imaging staging of prostate cancer.Methods. In October 2007 a multicentric observational perspective study called Multicentric Italian Report on Radical prostatectomy Outcome and Research (MIRROR) was started in 135 Italian urology centers. Recruitment was closed in December 2008 and 2,408 cases were collected. In this paper we have taken into consideration all examinations carried out for preoperative imaging staging, evaluating compliance with the recommen…
Clinical Delineation Of A Subtype Of Frontonasal Dysplasia With Creased Nasal Ridge And Upper Limb Anomalies: Report Of Six Unrelated Patients
2017
IF 2.259; International audience; Frontonasal dysplasias are rare congenital malformations of frontonasal process-derived structures, characterized by median cleft, nasal anomalies, widely spaced eyes, and cranium bifidum occultum. Several entities of syndromic frontonasal dysplasia have been described, among which, to date, only a few have identified molecular bases. We clinically ascertained a cohort of 124 individuals referred for frontonasal dysplasia. We identified six individuals with a similar phenotype, including one discordant monozygous twin. Facial features were remarkable by nasal deformity with creased ridge and depressed or absent tip, widely spaced eyes, almond-shaped palpebr…