Search results for " bone"
showing 10 items of 933 documents
Correlation between Density and Resorption of Fresh-Frozen and Autogenous Bone Grafts
2014
Trial Design. This analysis compared the outcome of fresh-frozen versus autologous bone block grafts for horizontal ridge augmentation in patients with Cawood and Howell class IV atrophies.Methods. Seventeen patients received autologous grafts and 21 patients received fresh-frozen bone grafts. Patients underwent CT scans 1 week and 6 months after surgery for graft volume and density analysis.Results. Two autologous and 3 fresh-frozen grafts failed. Autologous and fresh-frozen grafts lost, respectively, 28% and 46% of their initial volume(P=0.028). It is noteworthy that less dense fresh-frozen blocks lost more volume than denser grafts (61% versus 16%).Conclusions. According to these 6-month…
MRI radiomics-based machine-learning classification of bone chondrosarcoma.
2019
Abstract Purpose To evaluate the diagnostic performance of machine learning for discrimination between low-grade and high-grade cartilaginous bone tumors based on radiomic parameters extracted from unenhanced magnetic resonance imaging (MRI). Methods We retrospectively enrolled 58 patients with histologically-proven low-grade/atypical cartilaginous tumor of the appendicular skeleton (n = 26) or higher-grade chondrosarcoma (n = 32, including 16 appendicular and 16 axial lesions). They were randomly divided into training (n = 42) and test (n = 16) groups for model tuning and testing, respectively. All tumors were manually segmented on T1-weighted and T2-weighted images by drawing bidimensiona…
Implant treatment in atrophic posterior mandibles: Vertical regeneration with block bone grafts versus implants with 5.5-mm intrabony length
2014
Purpose: To retrospectively compare the outcomes of implants placed in posterior mandibles vertically regenerated with onlay autogenous block bone grafts and short dental implants. Materials and Methods: Consecutive patients with vertical bone atrophy in edentulous mandibular posterior regions (7 to 8 mm of bone above the inferior alveolar nerve) were treated with either implants placed in regenerated bone using autologous block bone grafts (group 1) or short implants (with 5.5-mm intrabony length) in native bone (group 2) between 2005 and 2010 and followed for 12 months after loading. The procedure used was the established treatment protocol for this type of patient at the Oral Surgery Uni…
Use of a new cross-linked collagen membrane for the treatment of dehiscence-type defects at titanium implants: a prospective, randomized-controlled d…
2009
OBJECTIVES The aim of the present randomized-controlled double-blinded clinical multicenter study was to assess the use of either a new cross-linked (VN) or a native collagen membrane (BG) for the treatment of dehiscence-type defects at titanium implants. MATERIAL AND METHODS A total of n=54 patients were recruited in four German university clinics. According to a parallel-groups design, dehiscence-type defects at titanium implants were filled with a natural bone mineral and randomly assigned to either VN or BG. Submerged sites were allowed to heal for 4 months. Primary (e.g., changes in defect length - DeltaDL, quality of newly formed tissue [0-4] - TQ) and secondary parameters (e.g., memb…
Clinical evaluation of nanocrystalline hydroxyapatite paste in the treatment of human periodontal bony defects--a randomized controlled clinical tria…
2008
The aim of this study was to compare the clinical outcome of intrabony periodontal defects following treatment with a novel nanocrystalline hydroxyapatite (NHA) paste to open flap debridement.Twenty-eight subjects, each displaying one intrabony defect with probing depth (PD)or =6 mm and radiographic evidence of an intraosseous componentor =3 mm participated in the present study. Subjects were allocated randomly to treatment with NHA paste (test group) or open flap debridement (control group). At baseline and at 6 months after surgery, the following clinical parameters were recorded by a masked examiner: plaque index, gingival index, PD, clinical attachment level (CAL), and gingival recessio…
The value of nuclear medicine for the diagnosis of spine diseases.
1993
Nuclear medicine examinations hold an important position in the diagnosis of diseases of the spine. During the last decade, decisive progress has been made in the field of instrumentation and radiopharmaceutical techniques: the use of high resolution collimators and the introduction of emission computer tomography as examples of improved instrumentation as well as 99m-Technetium red blood cell labelling as a new radiopharmaceutical technique. These present some of the developments responsible for the growing importance of scintigraphical diagnosis. Inflammatory processes of the vertebrae and the surrounding soft tissues can be detected or excluded with high reliability by the use of radionu…
Anatomic Changes After Hyoid Suspension for Obstructive Sleep Apnea: An MRI Study
2005
Objective To assess the effects of isolated hyoid suspension on subjective and objective parameters of obstructive sleep apnea and to evaluate changes in upper airway anatomy with the help of standardized magnetic resonance imaging. Study design and setting Fifteen patients received isolated hyoid suspension. Changes in respiratory disturbance index were assessed with polysomnography, and anatomical changes with standardized magnetic resonance imaging. Snoring, daytime sleepiness, and functional parameters were assessed with questionnaires. Lateral x-ray cephalometry was performed preoperatively. Results Mean respiratory disturbance index was reduced from 35.2 ± 19.1 to 27.4 ± 26.2. Forty p…
Surgical treatment and follow-up of solitary bone cyst of the mandible:a report of seven cases.
2001
We have operated on and followed up seven patients with simple mandibular bone cysts. The clinical data are shown in Table 1. All cysts were asymptomatic, and were found as a result of routine radiographs. They were all in dentulous areas in the mandible (5 in the anterior zone). Only case 5 gave a clear history of trauma in the region of the cyst 7 years before diagnosis. Vitality of the pulp of adjacent teeth was confirmed in all cases except case 6, in whom endodontic orthograde treatment of the teeth included in the lesion zone had previously been done. In all cases, the radiographs showed a unilocular radiotransparent lesion with clearly defined margins
Block iliac bone grafting enhances osseous healing of alveolar reconstruction in older cleft patients: A radiological and histological evaluation
2018
Background Older alveolar cleft patients (&12 years old) often have wide bone defect as well as teeth loss, resulting in poor osseous healing with conventional alveolar bone grafting (ABG). In this study, we investigated a surgical technique of block iliac bone grafting for the alveolar cleft reconstruction and evaluated the clinical and radiological outcomes of these cleft patients. Material and Methods Fifteen patients were included in this study. All cases received preoperative cone bean computed tomography (CBCT) scans for the alveolar cleft evaluation. Osseous outcomes of block iliac bone grafting were assessed at 1 week, 3- and 6-month postoperatively. Volume changes and bone resorpti…
The supracondylar approach to the jugular tubercle and hypoglossal canal.
1998
BACKGROUND Circumscribed lesions of the hypoglossal canal and of the jugular tubercle still remain a surgical challenge. So far, transpetrosal, transcondylar suboccipital, and extreme lateral approaches have been used to access this region. These surgical procedures bear a high risk for neurological deficits. Therefore, we introduce a new minimally invasive extradural approach to the hypoglossal canal that also allows access to the lateral aspects of the jugular tubercle. METHODS After a paramedian retromastoid skin incision, a basal suboccipital craniectomy lateral to the foramen magnum toward the jugular tubercle is performed. With this approach the occipital condyle and the lateral osseo…