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Adjacent Bone (adjacent + bone)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Reduced growth hormone receptor immunoreactivity in osteoclasts adjacent to the erupting molar in the incisor-absent (osteopetrotic) rat

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2003
Anne L. Symons
First molars fail to erupt in the incisor-absent (ia/ia) rat because of a defect in osteoclast function. Growth factors that regulate local bone metabolism include growth hormone (GH), insulin-like growth factor-I (IGF-I), epidermal growth factor (EGF) and interleukin-1 alpha (IL- 1,). Since osteoclast function may be affected by these factors, the aim of this study was to determine the distribution of GH receptor (GHr), IGF-I, EGF and IL-1,, in osteoclasts located occlusal to the erupting first molar, in the ,eruption pathway', in normal and ia/ia rats. Sagittal sections of the first molar and adjacent bone from 3- and 9-d-old animals were examined. Osteoclasts were identified using tartrate-resistant acid phosphatase (TRAP). The TRAP-positive osteoclast cell numbers were higher in ia/ia animals at 3 and 9 days-of-age. In the ia/ia group, fewer osteoclasts were GHr- and IGF-I-positive at 3 d of age, and at 9 d of age fewer osteoclasts were GHr-positive. In the ia/ia rat, defective osteoclast function failed to resorb bone to provide an eruption pathway for the lower first molar. The expression of GHr, and to some degree IGF-I, by these osteoclasts was reduced, which may be related to their ability to differentiate and function. [source]

Does orthodontic loading influence bone mineral density around titanium miniplates?

ORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 1 2010
An experimental study in dogs
To cite this article: Cornelis MA, Mahy P, Devogelaer JP, De Clerck HJ, Nyssen-Behets C: Does orthodontic loading influence bone mineral density around titanium miniplates? An experimental study in dogs Orthod Craniofac Res 2010;13:21,27 Structured Abstract Authors,,, Cornelis MA, Mahy P, Devogelaer JP, De Clerck HJ, Nyssen-Behets C Objectives,,, To evaluate whether orthodontic loading has an effect on miniplate stability and bone mineral density (BMD) around the screws supporting those miniplates. Setting and Sample Population,,, Two miniplates were inserted in each jaw quadrant of 10 dogs. Material and Methods,,, Two weeks later, coil springs were placed between the miniplates of one upper quadrant and between those of the contralateral lower quadrant. The other miniplates remained non-loaded. The dogs were sacrificed 7 or 29 weeks after surgery, and the jaws were scanned with peripheral Quantitative Computed Tomography (pQCT) to assess BMD. Results,,, The success rate was not significantly different for the loaded and the non-loaded miniplates, but was significantly higher for the maxillary compared to the mandibular ones. Mobility, associated with local inflammation, most often occurred during the transition between primary and secondary stability. pQCT showed higher BMD around mandibular vs. maxillary screws, without significant difference between loaded and non-loaded ones. Furthermore, load direction did not lead to any significant difference in BMD. Conclusion,,, Miniplate stability and BMD of the adjacent bone did not appear to depend significantly on orthodontic loading, but rather on the receptor site anatomy. [source]

Orbital leiomyoma: a case report with clinical, radiological and pathological correlation

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2005
Rohan Merani MB BS MMed
Abstract Orbital leiomyoma is a benign tumour of smooth muscle origin that can be clinically, radiologically and histopathologically difficult, to, diagnose, due, to, the, rarity, of, leiomyomas, in this location. A 74-year-old woman presented with a, 2-month history of painless proptosis. Computed tomography and magnetic resonance imaging studies revealed a well-circumscribed intraconal lesion separate from the optic nerve, and not eroding adjacent bone. A right lateral orbitotomy via a lid crease incision was performed to remove the firm lobulated lesion. Postoperatively there was an obvious decrease in proptosis. Microscopically the lesion was a well-circumscribed tumour composed of spindle cells. There were no light microscopic features to suggest malignancy, and immunohistochemistry was used to confirm the diagnosis of leiomyoma. Leiomyoma is a tumour that is rarely found in the orbit most likely due to the paucity of smooth muscle in this location. The differential diagnosis is wide, and the role of radiology, histology and immunohistochemistry in the diagnosis of leiomyoma is discussed. Surgical excision in this case excluded malignancy, provided a definitive diagnosis of a rare entity and resulted in marked clinical improvement. [source]

Ligament and bone pathologic abnormalities more frequent in neuropathic joint disease in comparison with degenerative arthritis of the foot and ankle: Implications for understanding rapidly progressive joint degeneration,

ARTHRITIS & RHEUMATISM, Issue 8 2010
Jill Halstead
Objective The variable disease progression of osteoarthritis (OA) and the basis for rapid joint deterioration in some subgroups of patients are poorly understood. To explore an anatomic basis for rapidly progressive OA, this observational study compared the magnetic resonance imaging (MRI) patterns of disease between patients with neuropathic joint disease (NJD) and patients with degenerative arthritis of the ankle and foot. Methods MR images of the foot and ankle of patients with early NJD (n = 7) and patients with OA (n = 15) were assessed. The anonomized MR images were dichotomously scored by a musculoskeletal radiologist for the presence of the following abnormalities per bone (of a total of 14 bones): cartilage defects, bone cysts, bone marrow edema, fractures, joint debris, joint effusions, tendinopathy, tendinitis, and ligament tears. Results Although the degree of cartilage damage and joint cyst formation was comparable between the groups, the degree of ligament tears, or change in MRI signal intensity in the ligaments, was significantly greater in patients with NJD compared with patients with OA (median of 3 tears versus 0, of 14 total bones; P < 0.01). Moreover, in patients with early NJD compared with patients with OA, there was a significantly greater degree of diffuse bone marrow edema (median of 6.5 tarsal bones versus 2 adjacent bones, of 14 total bones; P < 0.01), a greater number of bone fractures (median 4 versus 0; P < 0.01), and more frequent bone debris (median 4.5 versus 0; P = 0.013). Conclusion This analysis of NJD in the foot and ankle shows the predominance of bone and ligament abnormalities in NJD compared with the pattern of involvement in OA. These findings highlight the importance of structures other than articular cartilage in OA of the ankle and foot, and suggest that rapid joint degeneration in NJD may be more ligamentogenic or osteogenic in nature. [source]