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Association of an aromatase TTTA repeat polymorphism with circulating estrogen, bone structure, and biochemistry in older women.

Osteoporosis is a disease that is strongly genetically determined. Aromatase converts androgens to estradiol in postmenopausal women, therefore polymorphisms of the gene for this enzyme may be associated with bone mass and fracture. We investigated the association of the TTTA microsatellite polymorphism in intron 4 of the aromatase (CYP19) gene with bone mineral density (BMD) and fracture in 1,257 women aged 70 yr and greater. The data obtained were stratified based on the presence or absence of a [TTTA]n of 7 (A2), determined from a preliminary analysis of hip dual-energy X-ray absorptiometry

Osteotomy with 80-micros CO2 laser pulses--histological results.

Haemostatic and aseptic effects and intricate cut geometry are beneficial aspects of non-contact laser osteotomy. Collateral thermal damage, however, has severely limited the use of conventional lasers. The purpose of this study was to test the side effects on bone after cutting it with short CO2 laser pulses and simultaneous application of a fine air-water spray. The 10.6 microm CO2 laser emitted 80 micros pulses of 46 mJ energy, f=100 Hz, focused to a spot diameter of 130 ìm. Scan rate amounted to 40 mm/s. To approximate live conditions 10 samples of cortical bone and 10 rib segments were pr…

Bone mineral density in patients beginning hemodialysis treatment.

BACKGROUND: Our study was designed to determine bone mineral density (BMD) in patients beginning hemodialysis (HD) treatment, a possible correlation with the duration of renal failure prior to treatment, a possible correlation with the basic disease and the association with the concentration of intact parathormone (iPTH). METHODS: Our prospective clinical trial included 50 patients beginning HD treatment. Cortical bone mineral density (BMDc) was measured at the left femoral neck and trabecular bone mineral density (BMDt) in the region of the lumbosacral spine. Bone mineral density (BMD) was m…

A bone tissue integrated single fibre laser Doppler flowmeter probe.

Laser Doppler Flowmetry was developed and evaluated mainly for measuring blood flow in exposed or superficial tissue layers like skin. Resul … nitially creates some trauma to the vascular bed in the bone marrow but almost none in the opposite cortical bone layer. The healing process enhances the blood perfusion during the first weeks. The increased perfusion can be due to different parameters such as angiogenesis. The histological findings support this hypothesis. This gives preference to the tissue-i …

In vivo measurements of lead in bone at four anatomical sites: long term occupational and consequent endogenous exposure.

Measurements of bone lead concentrations in the tibia, wrist, sternum, and calcaneus were performed in vivo by x ray fluorescence on active and retired lead workers from two acid battery factories, office personnel in the two factories under study, and control subjects. Altogether 171 persons were included. Lead concentrations in the tibia and ulna (representative of cortical bone) appeared to behave similarly with respect to time but the ulnar measurement was much less precise. In an analogous fashion, lead in the calcaneus and sternum (representative of trabecular bone) behaved in the same w…

A mouse model of disuse osteoporosis based on a movable noninvasive 3D-printed unloading device.

OBJECTIVE: Disuse osteoporosis is a major type of bone loss disease characterized by regional bone loss and microstructure alterations. The … (ELISA). RESULTS: The micro-CT results showed significant trabecular bone loss, and 3D-ULD induced cortical bone loss in disused femurs as well as a decrease in the bone mineral density in the unloaded mice. TRAP staining and IHC-CTSK staining results indicated increases in the osteoclast number per bone perimeter (Oc.N/B.Pm) and the osteoclast surface per bon …

Feasibility of opportunistic dental diagnostics in routine photon-counting CT examinations of the cervical spine.

BACKGROUND: This study evaluates the potential of routine clinical photon-counting computed tomography (PCCT) of the cervical spine for opportunistic dental diagnostics. METHODS: Thirty-three patients undergoing routine PCCT were included in this study, with imaging performed at an average dose of 13 mGy. Images were reconstructed to a voxel size of 156 μm and a slice thickness of 0.4 mm. Quantitative image quality was assessed using the contrast-to-noise ratio (CNR) between dental structures, while qualitative assessment of structures like enamel, dentine, root canals, and cortical bone was …

Role of polyetheretherketone (PEEK) in arthroplasty and orthopaedics: a review of biomechanical properties, surface modifications, and clinical outcomes.

BACKGROUND: Polyetheretherketone (PEEK) has gained attention as an alternative to metallic implants in orthopaedic applications, including a … h, and systematic reviews. RESULTS: PEEK's elastic modulus (3-4 GPa) closely matches that of human cortical bone, potentially reducing stress shielding and enhancing osseointegration. Its inherent radiolucency improves imaging capabilities, while various surface modification techniques, including hydroxyapatite coatings and nanopatterning, have been developed …

Fibular mid-shaft stress fractures in a 4-year-old child: A case report and literature review of the first decade of children with fibular stress fracture.

Mid-fibular stress fractures are rare in the pediatric population and frequently present a diagnostic dilemma due to their subtle clinical presentation. In young, active children, the localized pain and associated periosteal reaction can closely mimic aggressive pathologies, such as primary bone malignancies or osteomyelitis, often leading to unnecessary parental anxiety and invasive diagnostic procedures. We report the case of a 4-year-old boy presenting with a 2-week history of an antalgic gait and localized tenderness over the left fibular shaft in the absence of acute trauma. While initial

Revision strategies following ESP-L lumbar disc arthroplasty complicated by osteolysis and recurrent symptoms.

BACKGROUND: Viscoelastic lumbar total disc replacements (TDRs) can develop periprosthetic osteolysis likely attributable to wear debris and … ology and implant stability. Case 1 had a large posterior osteolytic cavity and underwent posterior cortical bone trajectory (CBT) fusion with autologous bone grafting. Case 2, with a contained lesion adjacent to an otherwise stable implant, was treated with targeted percutaneous cement augmentation. RESULTS: Longitudinal imaging and clinical follow-up showed …

Candida Femoral Osteomyelitis in a Young Adult Without Known Risk Factors for Immunosuppression: A Case Report.

Fungal osteomyelitis is a rare and challenging infection that typically affects individuals with compromised immune systems. Its insidious presentation often leads to delays in diagnosis and treatment. We report Candida species femoral osteomyelitis in a previously healthy 20-year-old man without known risk factors for immunosuppression who presented with a six-month history of unilateral thigh pain and limping. Laboratory tests, including C-reactive protein (mildly elevated at 10 mg/L) and erythrocyte sedimentation rate (20 mm/hour), were near‑normal. Magnetic resonance imaging (MRI) revealed

The effects of prenatal administration of tumor necrosis factor-α on osteocalcin and RANK expression in newborn mice.

Tumor necrosis factor-α (TNF-α) induces a multitude of actions and consequences in bone and cartilage resorption and immune response augment … e performed on right lower limb of newborn mice. The expression of osteocalcin and RANK markers and cortical bone thickness showed no significant difference between the groups. There were no significant changes in osteogenesis parameters in this study. Some evidences have demonstrated the dual role of TNF-α on body tissues. However, future investigations should …

Critical Review of Hearing Rehabilitation in Pediatric Oncology: Specific Considerations and Barriers.

Childhood cancer treatments, including chemotherapy, radiation therapy, and combined modalities, pose significant risks to auditory function due to their ototoxic effects. Cisplatin, a chemotherapeutic agent commonly used in pediatric oncology, causes dose-dependent irreversible sensorineural hearing loss by damaging the inner ear structures, primarily through the generation of reactive oxygen species and the activation of apoptotic pathways. Radiation therapy exacerbates these effects, contributing to both sensorineural and conductive hearing loss via mechanisms such as vascular injury, infla

Gigantic lumbar aneurysmal bone cyst with abdominal extension in a pediatric patient: case report and its multidisciplinary management.

BACKGROUND: Aneurysmal bone cyst (ABC) is a rare, benign, and highly vascular osteolytic lesion characterized by expansile cystic spaces filled with blood and surrounded by thinned cortical bone. ABC is most commonly found in the vertebral column, most specifically in the posterior element of the lumbar spine. Management of spinal ABCs poses a challenge to the treating physician given its proximity to the neural structures. Surgical intervention, radiation therapy, cryotherapy, and embolization are effective treatment methods. However, no treatment protocol has been established in the literatu…

A Case of Opsismodysplasia with a Novel INPPL1 Variant.

INTRODUCTION: Opsismodysplasia is a rare autosomal recessive genetic skeletal disorder characterized by short stature, short limbs, small hands and feet, delayed bone age, severe platyspondyly, metaphyseal cupping, and facial dysmorphism. Opsismodysplasia is caused by biallelic variants in the INPPL1 gene. Only 38 patients with a confirmed molecular diagnosis have been reported so far. CASE PRESENTATION: We present a 9-month-old male patient who was referred to our clinic with a suspicion of mucopolysaccharidoses due to facial features and radiographic findings, but urine glycosaminoglycans w

CBCT imaging and histopathological characteristics of osteoradionecrosis and medication-related osteonecrosis of the jaw.

PURPOSE: The purpose of this study was to evaluate the cone-beam computed tomographic (CBCT) imaging and histopathological characteristics of osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ). MATERIALS AND METHODS: Ten surgical specimens from segmental mandibulectomy (3 ORN and 7 MRONJ) were analyzed using CBCT. The CBCT parameters were as follows: high-resolution mode (tube voltage, 90.0 kV; tube current, 4.00 mA; rotation time, 16.8 s; field of view, 56 mm×56 mm; thickness, 0.099 mm). Histopathological characteristics were evaluated using histological slides

The Influence of Local Pamidronate Application on Alveolar Dimensional Preservation after Tooth Extraction-An Animal Experimental Study.

The aim of this randomized, controlled animal exploratory trial was to investigate the influence of local application of aminobisphosphonate pamidronate during the socket preservation procedure. Mandibular premolars were extracted in five Göttingen minipigs. Two animals underwent socket preservation using BEGO OSS (n = 8 sockets) and three animals using BEGO OSS + Pamifos (15 mg) (n = 12 sockets). After jaw impression, cast models (baseline, eight weeks postoperative) were digitized using an inLab X5 scanner (Dentsply Sirona) and the generated STL data were superimposed and analyzed with GOM I

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… This bone structure differed significantly from the surrounding cortical bone of the lower jaw. In the former sockets, primarily, lamellar structures were found, whereas the surrounding area was dominated by osteons ( Figure 4 ). … Figure 4 Representative imaging of the bone structure in polarized light (staining: toluidine blue; magnification: 50×): ( a ) primarily parallel aligned, newly formed bone structure in the former tooth socket; ( b ) the remaining cortical bone shows a typical osteon structure (red arrow); ( c ) border …

Design and evaluation of a novel sub-scaffold dental implant system based on the osteoinduction of micro-nano bioactive glass.

Alveolar ridge atrophy brings great challenges for endosteal implantation due to the lack of adequate vertical bone mass to hold the implant … s design achieved alveolar ridge augmentation, as active osteogenesis could be observed outside the cortical bone. Considering that the microenvironment of the sub-epicranial aponeurosis space is similar to that of the alveolar ridge, SDISs have great potential for clinical applications in the treatment of atrophic alveolar ridges. The study was approved by the …

Results of quadratus femoris muscle pedicle bone grafting (Meyers' procedure) in the management of ununited femoral neck fractures.

PURPOSE: Femoral neck fractures in young patients are associated with increase complication risk. The objective of this study was to evaluate the results of quadratus femoris muscle pedicle grafting in the treatment of ununited femoral neck fractures. METHODS: This study includes 16 patients with ununited femoral neck fractures treated with quadratus femoris muscle pedicle graft. 7 patients had neglected femoral neck fractures while 9 had ununited femoral neck fractures after fixation. Quadratus femoris muscle with 2 × 1 × 1 cm (length-width-height) bone in its insertion was elevated and plac