Search results for " bone"
showing 10 items of 933 documents
Influence of soft tissue grafting, orofacial implant position, and angulation on facial hard and soft tissue thickness at immediately inserted and pr…
2018
Background Resorption of hard and soft tissues following immediate implant insertion is frequently reported. Data regarding the influencing factors on facial tissue thickness are rare. Purpose This retrospective study investigated the impact of connective tissue grafting, the orofacial angulation and position of immediately inserted and provisionalized implants on the facial hard and soft tissue thickness in the anterior maxilla within a 1- to 5-year follow-up. Material and methods Implants with the prerequisite of having preoperative and postoperative cone beam computed tomography (CBCT) and a follow-up of 1 to 5 years were included. Facial bone deficiencies were grafted flaplessly with au…
Surgical complications after endoscopic transsphenoidal pituitary surgery.
2009
Between January 2004 and June 2007 we conducted a retrospective analysis to assess post-operative complications related to endoscopic pituitary surgery in a series of 150 patients. Patients were treated with an endoscopic endonasal transsphenoidal approach to the sellar region for removal of pathological sellar and suprasellar lesions. We analysed the complications in groups according to the anatomical structures of the approach and the functional systems of the pituitary gland (anterior and posterior endocrine systems), and compared them to a large historical series using the traditional microsurgical transsphenoidal approach. Overall, we observed a decreased incidence of complications wit…
Predicting the failure in distal femur fractures.
2018
Abstract Introduction The incidence of nonunion after fractures of the distal femur is up to 6%. The distal femoral nonunion is a disabling disease that needs complex steps in his treatment. Aim of our study is to find predicting factors of non-unions. Materials and methods We retrospectively analyzed 116 cases of distal femoral fractures and 20 cases of non-unions. In both surgeries we analyzed: accuracy of reduction, stability of fixation, hardware used, residual medial or lateral bone defect, use of autologous or heterologous bone grafts. Results Malreduction, particularly axial defect, associated with unbalanced fixation, and a medial cortical bone defect of greater or lesser extent wer…
Vitamin K antagonists' use and fracture risk: results from a systematic review and meta‐analysis
2015
Background: Although vitamin K antagonists (VKAs) lower serum values of bone deposition markers, the link with osteoporosis and fractures remains controversial. Objectives: To assess whether the use of VKAs is associated with an increased prevalence and/or incidence of osteoporosis, fractures, or lower bone mineral density (BMD) values. Methods: We conducted a systematic PubMed and EMBASE literature search until August 31, 2014, and a meta-analysis of cross-sectional and longitudinal studies investigating fractures and BMD, comparing patients treated with VKAs and healthy controls (HCs) or with patients with medical illness (medical controls, MCs). Standardized mean differences ± 95% and co…
Rare sacral space-occupying lesions, their surgical management and reconstructive measures involved
1988
Nine cases of space-occupying lesions of the sacral bone are presented. The problems of the clinical diagnosis, which in many cases comes too late, are discussed together with the indications for surgical treatment in this special group of tumours. The main clues are provided by the changes in the X-rays as well as the more modern imaging techniques (CT and MRI). The surgical technique aims at a most radical tumour removal with preservation of the sacral nerve roots, after which stabilisation of the sometimes weakened pelvic girdle may be necessary. The good prospects of complete removal of these tumours of the sacrum with satisfactory results seem to be very little known and justifies furt…
Shape change in the atlas with congenital midline non-union of its posterior arch: a morphometric geometric study.
2017
Background Context The congenital midline non-union of the posterior arch of the atlas is a developmental variant present at a frequency ranging from 0.7% to 3.9%. Most of the reported cases correspond to incidental findings during routine medical examination. In cases of posterior non-union, hypertrophy of the anterior arch and cortical bone thickening of the posterior arches have been observed and interpreted as adaptive responses of the atlas to increased mechanical stress. Purpose We sought to determine if the congenital non-union of the posterior arch results in a change in the shape of the atlas. Study Design/Setting This study is an analysis of the first cervical vertebrae from osteo…
Long-term bony integration and resorption kinetics of a xenogeneic bone substitute after sinus floor augmentation: histomorphometric analyses of huma…
2013
In this case series, a systematic histomorphometric analysis of two human bone biopsy specimens was conducted 1 and 5 years after grafting with a xenogeneic bovine bone substitute material (BSM). While the 1-year specimen still showed extensive signs of an active desmal ossification, the specimen after 5 years mainly showed mature lamellar bone without bone turnover or remodeling. A completed bony integration without extensive resorption of the BSM particles could be detected. Altogether, a good integration in the bone with osteoconduction and a high biocompatibility was seen.
Thanatophoric dysplasia in monozygotic twins discordant for cloverleaf skull: Prenatal diagnosis, clinical and pathological findings
1992
We present male monozygotic twins with thanatophoric dysplasia (TD) type I concordant for long bone abnormalities and discordant for cloverleaf skull. The twins were the product of the second pregnancy of unrelated parents, with advanced paternal age. Prenatal diagnosis and postmortem examination showed severe rhizomelic shortness of limbs, bowing of the long bones with "telephone-receiver" femora in both twins, and cloverleaf skull and hydrocephalus in one of them. It is now accepted that most of cases of TD, such as in the present report, represent an autosomal dominant mutation with a high new mutations rate.
Modeling the impact of soft tissue on axial transmission measurements of ultrasonic guided waves in human radius
2008
Recent in vitro and simulation studies have shown that guided waves measured at low ultrasound frequencies (f=200 kHz) can characterize both material properties and geometry of the cortical bone wall. In particular, a method for an accurate cortical thickness estimation from ultrasound velocity data has been presented. The clinical application remains, however, a challenge as the impact of a layer of soft tissue on top of the bone is not yet well established, and this layer is expected to affect the dispersion and relative intensities of guided modes. The present study is focused on the theoretical modeling of the impact of an overlying soft tissue. A semianalytical method and finite-differ…
Impact of crestal and subcrestal implant placement in peri-implant bone: a prospective comparative study
2015
Background To assess the influence of the crestal or subcrestal placement of implants upon peri-implant bone loss over 12 months of follow-up. Material and Methods Twenty-six patients with a single hopeless tooth were recruited in the Oral Surgery Unit (Valencia University, Valencia, Spain). The patients were randomized into two treatment groups: group A (implants placed at crestal level) or group B (implants placed at subcrestal level). Control visits were conducted by a trained clinician at the time of implant placement and 12 months after loading. A previously established standard protocol was used to compile general data on all patients (sex and age, implant length and diameter, and bru…