Loss Of Bone Structure Research Articles

THE IMPACT OF SEX ON BONE STRUCTURE AND ANGIOGENESIS IN SYNDECAN-1 DEFICIENT MICE

Neoangiogenesis drives the replacement of mineralised cartilage by trabecular bone during bone growth regulated by molecules like e.g. VEGF, OPG and RANKL. The Heparan sulfate proteoglycan Syndecan-1 (Sdc1) plays a role in the interaction of osteoclasts and osteoblasts and the development of blood vessels. We expected Sdc1 to have an influence on bone structure and vessel development. Therefore, bone structure and angiogenesis at the growth plate in mice was compared and the influence of Syndecan-1 deficiency was characterised.Animals: Femura of male and female C57BL/6 WT (5♀, 6♂) and Sdc1-/- (9♀, 5♂) mice were used for native bone analysis at 4 month age. Histology: Bone structure was analysed using microCT scans with a resolution of 9µm. Vascularisation was visualised using an anti-Endomucin antibody in 80µm thick cryosections. In vitro angiogenesis: Bone marrow isolates were used to generate endothelial progenitor cells by sequential cultivation on fibronectin. Microvessel development was analysed 4h after plating on matrigel.Bone structure in male Sdc1 deficient mice was significantly reduced compare to male WT, whereas female mice of both genotypes did not differ. Sdc1 deficient mice at the age of 4 month showed a high decrease in the number of vessel bulbs at the chondro-osseous border (growth plate) compared to WT mice. However, no sex related differences were shown. Quantification of microvessel outgrowth of endothelial cells revealed a decreased amount of sprouting, but increased length of microvessels of Sdc1-/- cells compared to WT.Syndecan-1 has a significant impact on neoangiogenesis at the chondro-osseous border of the native bone, but the impact of Syndecan-1 deficiency on the loss of bone structure was significantly higher in male mice. This emphasises the importance to further characterise the function of Syndecan-1 regulated processes during enchondral ossification in a sex dependent manner.

CALCIFYING ODONTOGENIC CYST WITH 10 YEARS OF EVOLUTION: A CASE REPORT

Calcifying odontogenic cyst (COC) is a rare, benign odontogenic lesion that sometimes may be present along with odontogenic tumors. A 22-year-old female patient was referred for evaluation of an asymptomatic swelling on the anterior maxilla with approximately 10 years of evolution. Physical examination showed firm swelling with cortical expansion within intact bluish mucosa. Computed tomography showed a unilocular hypodense image with hyperdense foci, causing loss of bone structure in the vestibular cortical and anterior wall of maxillary sinus. Diagnostic hypotheses were calcifying epithelial odontogenic tumor, ameloblastic fibro-odontoma, and complex odontoma, and incisional biopsy was performed. Microscopic analysis revealed a pathologic cavity lined by odontogenic epithelium with variable thickness, along with ghost cells, eosinophilic acellular material resembling dentinoid, and foci of dystrophic calcifications. The cyst was surrounded by a fibrous capsule. Histopathologic diagnosis was COC. The patient was referred for enucleation of the lesion for complete analysis and final diagnosis.

Loss of definition of the submental contouring: correct diagnosis and treatment algorithm

The search for aesthetic procedures aimed at the loss of submental definition is increasing. A correct diagnosis is imperative for successful treatment and the reduction of complications. Localized adiposity, skin flaccidity, and loss of bone structure are the main findings. A treatment algorithm was discussed in this review, remembering, of course, the possibility of combined and sequential treatments for better results.

CALCIFYING ODONTOGENIC CYST IN AN OLDER PATIENT: A CASE REPORT

Calcifying odontogenic cyst (COC) is a rare odontogenic developmental cyst representing less than 2.0% of all odontogenic lesions. We report a case of an 89-year-old female presenting with a massive painful swelling in the right posterior mandible. Cone beam CT scans showed a large, hypodense unilocular lesion, causing loss of bone structure in the angle, body, and ramus of the mandibular right side. An incisional biopsy was performed. Histologically, there were pathologic cavity lines by odontogenic epithelium rich in ghost cells and foci of dystrophic calcifications, surrounded by a fibrous capsule. The diagnosis was COC. A segmental resection followed by reconstruction was carried out, and the patient has been in follow-up since August 2018. COC is one of the rarest lesions in the oral region. Despite its benign nature, cases of aggressive COC have been reported. A discussion on the pathologic analysis and surgical approach will be provided in this presentation.

A Novel Modification of the Sagittal Split Osteotomy as an Access Osteotomy.

Pathologies present in the central zone of the mandible are difficult to access, primarily because of the presence of the inferior alveolar nerve (IAN) and the need to remove a large corticocancellous component to reach the area of interest. Many times, this bony window is replaced as a free graft and there is complete resorption in the long term or even rejection of the graft causing a bony defect which can weaken the mandible. Furthermore, the damage to the IAN is profound. To try and avoid these comorbidities the traditional sagittal split osteotomy was modified to access a central osteoma impinging on the IAN and the successful removal of the same without any comorbidities such as paraesthesia or loss of bone structure. We believe that this modification can be used for other scenarios such as benign cysts and difficult presentations of impacted teeth.

Magnetic resonance evaluation of the interrelationship between articular cartilage and trabecular bone of the osteoarthritic knee

Objective: To use high-resolution magnetic resonance imaging (MRI) to determine the relationship between articular cartilage degeneration and trabecular bone changes of the femur, condyles and tibia in human knees with osteoarthritis (OA). Methods: Subjects were divided into three groups: without OA (OA0), mild OA (OA1) and severe OA (OA2). Sagittal images of the knee (0.234×0.234 mm 2, 2-mm slice thickness) were obtained at 1.5T and used for calculating the volume and thickness of the femoral and tibial cartilage. Axial images (0.195×0.195 mm 2, 1-mm slice thickness) were used for calculating the trabecular bone structure parameters: apparent bone volume fraction, trabecular number, trabecular separation and trabecular thickness. Results: Cartilage volume and thickness were less in patients with OA compared to normal controls ( P<0.1). Articular cartilage thinning is associated with bone structure loss in the opposite femoral condyle ( P<0.05). In varus OA, there were extensive correlations between medial tibia and medial femoral cartilage degeneration, and loss of bone structure in the lateral tibia and lateral condyle. Additional correlations existed between the compartmental differences (lateral minus medial) of cartilage thickness and bone structure. Conclusion: Degradation of articular cartilage within a compartment correlates with a loss of bone structure in the opposite compartment. The correlation between the (L-M) differences corroborates this relationship. Malalignment of the knee due to cartilage degeneration is associated with bone formation in the diseased condyle and bone resorption in the opposite compartment.

Fate of Bone Grafts in Acetabular Roof Reconstructions Assessed by Roentgenography and Scintigraphy

Autogeneic bone grafts--26 femoral heads, four femoral and two iliac bone grafts--were used in 32 total hip arthroplasties, mainly on patients with complete dislocation of the hip, to reconstruct deficiencies of the acetabular roof by a standardized procedure. At the follow-up examination after 24 to 101 months (median, 52 months), roentgenography demonstrated lateral resorption of the graft in 20 of 32 hips, but resorption involved bone support of the socket in only three of the hips. Analysis of serial roentgenograms showed that resorption was not a function of time. Complete incorporation of the grafts was observed in 27 hips; partial incorporation was shown in three. Roentgenographically, two grafts were not incorporated. None of three grafts of a cortical nature was incorporated. Graft uptake of radioactive tracer was found by 99mTc-diphosphonate emission scintigraphy in 16 of 21 hips, but did not correlate with progressive bone resorption, nonunion, or loss of bone structure. High quality serial roentgenograms showing good bone detail provided the best information about the integrity of the acetabular roof reconstructions.

Hip salvage by proximal femoral replacement.

Total hip arthroplasty with a special segmental replacement of the proximal end of the femur which varied in length from eighty to 150 millimeters was performed in twenty-one patients who had severe non-neoplastic conditions of the proximal part of the femur that necessitated salvage. Ten patients had previously failed arthroplasties associated with loss of bone structure; seven had non-union of a proximal femoral fracture or osteotomy associated with severe hip disease; there had a failed resection arthroplasty; and one had an arthrodesis and incapacitating low-back pain. Clinical and roentgenographic data during follow-up of twenty-five to ninety-two months showed that only one patient had loosening of the acetabular component. In twenty of the twenty-one patients, total hip arthroplasty with proximal femoral replacement was effective in restoring the integrity of the bone and restoring function of the hip.

Jaws of adult culled ewes

SUMMARYThe jaws of 481 adult culled ewes were examined visually and radiographically for dental abnormality and changes in skeletal structure; the findings were correlated with ante-mortem body condition score and breed. Only two ewes had normal buccal morphology; the remainder of the sample showed a range of abnormalities which included loose and missing teeth, gingival hypertrophy, food-filled gingival pockets, ridging and shearing of the occlusal surfaces. There was a general loss of bone structure. Dental abnormality was not strongly correlated with breed but showed a significant relationship with radiographic assessment of bone density. Body condition did not appear to be adversely affected by dental disease. Skull dimensions and dental pad position were strongly associated with breed. The state of the incisor teeth alone was a poor indicator of cheek tooth condition.

Prosthetic replacement of the knee and a large segment of the femur or tibia.

Total replacement of the knee and of a long segment of the femur or tibia provided functional recovery of the knee joint in thirteen patients in whom the length of the bone replaced ranged from seventy-five to 150 millimeters. Nine patients had benign bone tumors, three had malignant lesions, and one patient had salvage of a failed total knee arthroplasty, associated with loss of bone structure. After follow-up of two years or more, all patients had a stable extremity, excellent relief of pain, and a useful range of motion, although one patient required revision for loosening.