Trabeculae Of Cancellous Bone Research Articles

Alveolar Ridge Preservation Using a Novel Species-Specific Collagen-Enriched Deproteinized Bovine Bone Mineral: Histological Evaluation of a Prospective Case Series.

In recent years, the significance of maintaining the alveolar ridge following tooth extractions has markedly increased. Alveolar ridge preservation (ARP) is a commonly utilized technique and a variety of bone substitute materials and biologics are applied in different combinations. For this purpose, a histological evaluation and the clinical necessity of subsequent guided bone regeneration (GBR) in delayed implantations were investigated in a prospective case series after ARP with a novel deproteinized bovine bone material (95%) in combination with a species-specific collagen (5%) (C-DBBM). Notably, block-form bone substitutes without porcine collagen are limited, and moreover, the availability of histological data on this material remains limited. Ten patients, each scheduled for tooth extraction and desiring future implantation, were included in this study. Following tooth extraction, ARP was performed using a block form of C-DBBM in conjunction with a double-folded bovine cross-linked collagen membrane (xCM). This membrane was openly exposed to the oral cavity and secured using a crisscross suture. After a healing period ranging from 130 to 319 days, guided trephine drilling was performed for implant insertion utilizing static computer-aided implant surgery (s-CAIS). Cores harvested from the area previously treated with ARP were histologically processed and examined. Guided bone regeneration (GBR) was not necessary for any of the implantations. Histological examination revealed the development of a lattice of cancellous bone trabeculae through appositional membranous osteogenesis at various stages surrounding C-DBBM granules as well as larger spongy or compact ossicles with minimal remnants. The clinical follow-up period ranged from 2.5 to 4.5 years, during which no biological or technical complications occurred. Within the limitations of this prospective case series, it can be concluded that ARP using this novel C-DBBM in combination with a bovine xCM could be a treatment option to avoid the need for subsequent GBR in delayed implantations with the opportunity of a bovine species-specific biomaterial chain.

Agomelatine alleviates steroid-induced osteoporosis by targeting SIRT1/RANKL/FOXO1/OPG signalling in rats.

One of the major contributors to secondary osteoporosis is long-term glucocorticoid usage. Clinically used antidepressant agomelatine also has anti-inflammatory properties. Our research aimed to inspect the probable defensive effect of agomelatine against steroid-promoted osteoporosis. There were four groups of rats; group I had saline as a negative control; rats of group II had dexamethasone (0.6 mg/kg, s.c.), twice weekly for 12 weeks; rats of group III had agomelatine (40 mg/kg/day, orally), as a positive control, daily for 12 weeks; and rats of group IV had dexamethasone + agomelatine in the same previous doses combined for 12 weeks. Finally, biochemical as well as histopathological changes were evaluated and dexamethasone treatment caused osteoporosis, as evidenced by discontinuous thin cancellous bone trabeculae, minor fissures and fractures, irregular eroded endosteal surface with elevated alkaline phosphate, tartarate resistant acid phosphate (TRACP) and osteocalcin levels. Osteoprotegerin (OPG), calcium, and phosphorus levels decreased with disturbed receptor activator of nuclear factor κ B ligand (RANKL), forkhead box O1 (FOXO1), and silent information regulator 1 (SIRT1)protein expression. However, treatment with agomelatine restored the normal levels of biochemical parameters to a great extent, supported by SIRT activation with an improvement in histopathological changes. Here, we concluded that agomelatine ameliorates steroid-induced osteoporosis through a SIRT1/RANKL/FOXO1/OPG-dependent pathway.

Light and scanning electron microscopic study of the effects of platelet-rich plasma on dexamethasone-induced osteoporosis in adult male albino rats

Abstract Background Osteoporosis may occur by using glucocorticoids for a long time. Recently, platelet-rich plasma (PRP) is used in treating a wide variety of musculoskeletal problems. Aim This work aimed to study the effect of PRP against dexamethasone-induced osteoporosis in adult male albino rats. Materials and methods This study was carried out on 40 adult male albino rats that were divided into two main groups: control group I: included 10 rats and experimental group II included 30 rats, which were subdivided into three subgroups. Subgroup IIa received PRP, subgroup IIb was injected with dexamethasone intramuscularly, and subgroup IIc received the same dose of dexamethasone and then injected with PRP. At the end of the experiment, upper ends of femur bones of all animals were obtained and processed for histological study using light and scanning electron micrograph studies. Results Light microscopic examination revealed osteoporotic histological changes in group IIb where cancellous bone trabeculae appeared thin and discontinuous. Scanning electron micrograph studies confirmed the results of the light microscopic study. Group IIc revealed partial preservation of the normal histological picture. Statistical analysis showed that group IIb and untreated left femur of group IIc revealed a highly significant decrease in the mean thickness of trabeculae and a highly significant increase in the width of intertrabecular spaces as compared with the control group, while group IIa and treated right femur of group IIc revealed nonsignificant changes as compared with the control group. Conclusion Osteoporosis resulted from glucocorticoids in adult male albino rats could be partially treated with PRP injection.

Measuring Young's modulus of single trabeculae in cancellous bone using a two-point bending test

BackroundSurgical treatment of proximal humeral fractures poses a major challenge, especially in osteoporotic bone. At present, there appears to exist neither a suitable model for research to optimize the osteosynthesis processes nor are the structural data available which are required for developing such a model. Therefore, the aim of this study is to determine the microscopic morphology and Young's modulus of cancellous bone from human humeral heads considering osteoporotic changes. MethodsCylindrical samples were taken from ten fresh-frozen human humeral heads and structural analysis was done with μCT. Ten rod-like trabeculae were prepared from five of the humeral heads each which were measured and tested mechanically. For this purpose, the trabeculae were fixed on a slide and rotated axially under a stereo microscope. The sample cross-section and the depending moment of inertia were extracted from the image data. The samples were then loaded in a 2-point bending test and Young's moduli of the samples were determined. ResultsIt could be shown that with increasing age of the donor, ossified portion of the cancellous bone decreased (p < 0.05). The average degree of mineralization of the bone was 1.24 (±0.06) g/mm3, which decreased with increasing age (p < 0.05). The determined Young's modulus averaged 1.33 (±1.76) GPa. InterpretationThe verified structural parameter showed osteoporotic changes in the examined bone. This study for the first time determined Young's modulus of single trabeculae of cancellous bone of osteoporotically altered human humeral heads. Implementing the non-destructive sample measurement before exposure resulted in a methodical improvement.

Effect of alfacalcidol on bone regeneration in senile rats

Background. Among the drugs that have a pleiotropic effect on bone, attention is drawn to alfacalcidol – the precursor of the active form of D-hormone. There are studies that have revealed distinctive features of the effect of alfacalcidol on bone regeneration in osteoporosis and in young animals. The purpose was to study bone regeneration after treatment with alfacalcidol in senile animals. Materials and methods. A transcortical defect from the lateral to the medial femur was modeled in rats aged 24 months in the area of the metadiaphysis. A treatment with alfacalcidol was carried out from the 2-nd day and for 10 and 30 days before the animals was withdrawn from the experiment. Histological study of bone regeneration with morphometric analysis of tissues in the areas of callus had been performed. Results. On the 10-th day of the treatment with alfacalcidol in senile animals, connective tissue, osteoid and coarse-fibrous trabecular bone with a high density of osteoblasts were located in the defect area. On the 30-th day in treated animals, the bone tissue of the callus was mature; its area was larger than in untreated animals. In the area of cancellous bone there is a network of newly formed bone trabeculae. Destructive manifestations around the defect were reduced in animals treated with alfacalcidol. In untreated animals there was no dense bone fusion with cortex fragments; trabeculae of cancellous bone were intermittent. In the lateral part of the callus, the area of bone tissue was reduced compared to the medial part. Conclusions. Treatment of animals with alfacalcidol accelerates the formation of bone tissue in the defect and reduces destructive manifestations around the defect compared to untreated animals.

Protective Effect of Rho-Associated Protein Kinase (ROCK) Activated by Bone Marrow Mesenchymal Stem Cells on Bone Strength and Osteoblasts in Rats with Osteoporosis

This study assesses BMSCs’ effect on bone strength and osteoblast activity in rats with osteoporosis. 40 SD female rats were assigned into normal (A) group, model (B) group, puerarin (C) group, and BMSCs (D) group followed by analysis of bone strength by small animal bone strength analyzer and the expression of ROCK1 protein in tibia by immunohistochemistry. The bone strength of group B was lower than group A (P &lt; 0.05), and higher in groups C and D than group B (P &lt; 0.05) with further higher in group D than group C (P &lt; 0.05). Group A showed obvious mesh cancellous bone trabecular bone and continuity, compact structure, and group B cells appeared loose and irregular distribution, parts cancellous bone trabeculae decrease and part of the fracture, and arranged in sparse irregular distribution. The decrease of trabecular bone in group C and D is not more obvious than group B and the morphology in group D got better improved than in group C. Group B showed lower proliferation of osteoblasts and ALP activity than group A (P &lt; 0.05) and the proliferation and ALP activity in groups C and D was increased significantly compared with group B (P &lt; 0.05). ROCK1 expression was significantly lower in group B than group A (P &lt; 0.05) higher in groups C and D than group B (P &lt; 0.05). Bone marrow mesenchymal stem cells (BMSCs) can effectively increase the bone strength and activity of osteoblasts in rats with osteoporosis, and promote the activation of ROCK signal.

Determination of E-modulus of cancellous bone derived from human humeri and validation of plotted single trabeculae: Development of a standardized humerus bone model

BackgroundEvaluation of the mechanical behavior of the microstructure of cancellous bone seems important for the understanding of the mechanical behavior of bone. Prevention and treatment of fragility fractures due to osteoporosis is a major challenge according to ageing population. A bone model might help to assess fracture risk. Measurement of single trabeculae of bone should give further information compared with bone densitometry alone. This study measures the mechanical properties of single cancellous trabeculae derived from human proximal humerus. Methods34 single trabeculae dissected from human humeral heads were measured and evaluated mechanically. Trabeculae were fixed on microscope slides and geometrical data were reported during axial rotation of the specimens to measure the transverse section using computer aided design (CAD). The samples were subjected to a two-point bending test and were loaded with a measure-stamp at a defined distance. Force and deflection were measured by high-resolution sensors. The E-modulus was then calculated in combination with finite elements method simulation (FEM), using the previously obtained CAD-Data. ResultsThe average E-modulus from 34 valid measurements of human humeral trabeculae was 1678 MPa with a range from 829 to 3396 MPa, which is consistent with existing literature. The planned additional validation of the measurement method using manufactured three-dimensional synthetic trabeculae with known mechanical properties showed an average elastic modulus of single trabeculae of 51.5 MPa, being two dimensions lower than the value reported in the datasheet of the plastic. ConclusionThis newly developed, time and cost-efficient procedure allows the measurement of E-modulus in single trabeculae. Measurement of mechanic parameters of single trabeculae might give insights on mechanic behavior of bone and be relevant for the research of systemic bone diseases, complementing the existing data on bone-mineral-density. Further examination of single trabeculae of human cancellous bone should give an insight on the mechanical behavior of bone also considering systemic bone diseases.

Long-Term Exposure to Low-Dose Lead Induced Deterioration in Bone Microstructure of Male Mice.

The aim of this study was to investigate the long-term effects of low-dose lead exposure on bone microstructure in mice. Ten SPF 12-week-old male C57BL/6J mice were randomly divided into two groups: control (deionized water) and lead exposure (150ppm of lead acetate in drinking water). After 24weeks treatment, mice were weighed and the left femurs were collected and stored at - 80°C. The right femurs of the mice were scanned by Micro-CT for three-dimensional reconstruction, and bone mineral density, bone volume fraction, trabeculae thickness, trabeculae number, and trabeculae separation were measured. The right tibia was collected to investigate histopathological changes in H&E-stained sections. The gene expression of osteoprotegerin (OPG), RANKL, and runt-related transcription factor 2 (Runx2) was determined using real-time PCR. The bone density of femoral cancellous bone and the number of cancellous bone trabeculae in the lead exposure group were both significantly decreased compared with the control group. Bone marrow stromal cell numbers were decreased following lead administration, and lipid droplet vacuoles were observed in the lead group. Levels of OPG were significantly decreased in the lead group, and lead also inhibited the expression of Runx2 compared with the control group. Long-term exposure to low doses of lead can cause bone damage without inducing other obvious symptoms through decreasing bone density and the number of cancellous bone trabeculae, further suppressing bone formation. It suggests that lead may exacerbate bone loss and osteoporosis, especially in the elderly.

Histological Study of the Possible Protective Effect of Lycopene on Glucocorticoid-Induced Osteoporosis in Adult Male Albino Rat

AbstractBackground: Osteoporosis is one of the most commonly occurring bone diseases characterized by decrease in bone mass and increase bone resorption leading to fractures, severe pain and deformities. Glucocorticoid-induced osteoporosis results from long-term and high dose use. Lycopene is an unsaturated carotenoid that gives tomatoes and other fruits their red color. It was reported that it is a natural antioxidant and was associated with the prevention of many chronic diseases and cancers.Aim of Study: This work was performed to study the possible protective effect of lycopene against glucocorticoid-induced osteoporosis in adult male albino rat.Material and Methods: 40 adult male albino rats were used that divided equally into four main groups: Group I (control group) was subdivided equally into two subgroups (I-A & I-B), Group II received lycopene orally 30mg/kg once daily for 8 weeks, Group III received prednisolone orally 20mg/kg once daily for 8 weeks, Group IV concomitantly received lycopene and prednisolone orally once daily at the same previous doses for 8 weeks. At the end of experiment, femur heads of all animals were obtained and processed for histological study and stained with Hematoxylin & eosin, Mallory Trichrome and for scanning electron microscope study.Results: Light microscopic examination revealed structural changes in femur head of Group III in the form of discontinuous thin trabeculae of cancellous bone with apparent faintly stained matrix with multiple pores inside trabeculae associated with minor fractures, wide bone marrow spaces were seen between trabeculae containing abundant clear areas, the endosteal surface showed irregular eroded surface. Regarding Mallory stained sections; they showed decrease collagen fibers contents with their irregular distribution in bone matrix. Scanning electron microscopic specimens showed discontinuous thin and blind ended cancellous bone trabeculae containing some areas of decreased electron density with multiple pores and minor fractures inside them. Wide bone marrow spaces were seen between trabeculae lined with irregular eroded endosteal surface; which revealed the evident of prednisolone induced osteoporosis. Group IV specimens revealed partial preservation of the normal structure of cancellous bone of femur head to some extent.Conclusion: Osteoporosis resulted from glucocorticoids in adult male albino rats can be partially minimized by lycopene co-administration.

Evaluation of the rivastigmine role against botulinum toxin-A-induced osteoporosis in albino rats: A biochemical, histological, and immunohistochemical study.

The present study aimed to evaluate the role of rivastigmine against the effect of a single unilateral botulinum toxin-A (BTX-A) injection on the bone and bone marrow of adult albino rats 4 weeks after injection. Twenty-four Wistar albino rats were divided into four equal groups: group I, which received distilled water; group II, which received rivastigmine (0.3 mg/kg daily, intraperitoneally for 4 weeks); group III, which received BTX-A (4 IU in 0.2 mL physiological saline) single dose, intramuscularly; and group IV, which received BTX-A + rivastigmine. The results revealed that BTX-A induced a significant decrease in the calcium level with a significant increase in the phosphorus, alkaline phosphatase, C-reactive protein, and tumor necrosis factor α levels in serum. Furthermore, a significant increase in malondialdehyde with a significant decrease in reduced glutathione activities in both bone and bone marrow. Histologically, a distortion and thinning out of the compact bone and trabeculae of cancellous bone of the rat femur in the BTX-A group with an increase in adipocytes in adjacent bone marrow were detected. Immunohistochemically, Cluster of Differentiation 68 (CD68) showed a significant increase in both osteoclasts and bone marrow macrophage. Rivastigmine treatment could relieve the toxic effects induced by BTX-A. In conclusion, rivastigmine has a protective effect against the hazardous effects of BTX-A on bone and bone marrow.

Three-dimensional morphometric properties of rod- and plate-like trabeculae in adolescent cancellous bone

SummaryBackground/ObjectiveDespite many researches have been carried out on the three-dimensional microarchitecture of cancellous bone, the morphometric properties of rod and plate trabeculae in adolescent cancellous bone have not yet been investigated. This study aimed to investigate three-dimensional morphometric properties of rod- and plate-like trabeculae in normal adolescent cancellous bone, and to compare them with adult cancellous bones to reveal morphometric changes from adolescence to adult life to obtain more insight into the subchondral bone adaptations during development and growth.MethodsThis study included 23 normal human proximal tibiae. These tibiae were divided into three groups: adolescents (9–17 years, n = 6), young adults (18–24 years, n = 9), and adults (25–30 years, n = 8). From each tibia, six cubic cancellous bone samples (dimensions 8 × 8 × 8 mm3) were sawed from each medial and lateral condyle, yielding a total of 276 samples. These samples were scanned using micro computed tomography leading to three-dimensional cubic voxel sizes of 10.5 × 10.5 × 10.5 μm3. The morphometric parameters of individual rod- and plate-like trabeculae were calculated and compared among three age groups.ResultsSignificant differences in some morphometric parameters were revealed. The mean longitudinal length of rods was significantly greater in the adolescents than in the young adults. Plate volume density showed an increasing trend with age, although not significant. Trabeculae were more plate-like in adolescents in the medial condyle of adolescents than in the lateral condyle, and changed towards more plate-like trabeculae in the adults. The single best predictor for the mechanical properties was apparent density. Apparent density alone explained 59% variations in Young’s modulus, 77% in ultimate stress and 34% in failure energy, respectively (all p < 0.01). Morphometric parameters might improve this prediction.ConclusionIn conclusion, this study has reported for the first time the morphometric parameters of rod- and plate-like trabeculae in adolescent proximal tibial cancellous bone, which will improve our understanding of morphometric changes in individual trabeculae during development and growth. Furthermore, separate analysis of individual rods and plates may also help reveal disease-related morphometric changes beyond bone mineral density.The translational potential of this articleA thorough quantification of individual trabeculae during development and growth may help understand disease-related 3-D morphometric changes beyond bone mineral density.

Therapeutic Role of Punica Granatum (Pomegranate) Seed Oil Extract on Bone Turnover and Resorption Induced in Ovariectomized Rats.

Postmenopausal osteoporosis is mostly caused by increased bone remodeling resulting from estrogen deficiency. Hormone replacement therapy (HRT) is used to prevent osteoporosis, but it increases the risk for breast cancer, thromboembolism, strokes, and heart attacks. Pomegranate seed oil extract (SOE) is rich in phytoestrogen and antioxidant compounds. To evaluate the therapeutic role of SOE against bone turnover, resorption and osteoporosis induced in ovariectomized rats as a postmenopausal model and comparing the results with those from Generic CycloProgynova drug (D). The study used western albino rats undergo bilaterally ovariectomization as a model for postmenopausal. The study took part in a laboratory setting. Forty female western albino rats (age: 3-4 months) weighing 150-180 gm. Rats were divided into four groups, 10 rats each; SC-group: Sham control = untreated and unovariectomized rats; OVX-group = ovariectomized rats; (OVX-SOE) and (OVX-D) groups = OVX rats were treated with SOE and D, respectively. Bone markers (BMs) especially osteocalcin (BGP), alkaline phosphatase (ALP), tartarate resistance acid phosphatase (TRAcP), bone weight, bone calcium concentration, serum electrolytes (calcium, sodium and potassium) and serum estradiol (E2) level and histopathological examination of bones were determined. Also lipid profile, uric acid, prothrombin time (INR) and liver and kidney functions were measured to evaluate the adverse effects of SOE and D. In OVX group the activities of ALP and TRAcP and the levels of BGP, serum calcium, sodium and body weight were significantly higher (p≤0.05) than SC-group, while bone calcium concentration, bone mass, serum E2 and potassium level as well as uterus mass were significantly lower (p≤0.05). Also histopathological results revealed that the outer cortical bone became thinner, while the cancellous bone trabeculae lost their normal architecture. Moreover in OVX group lipid profile and uric acid levels were significantly higher (p≤0.05) than SC group, but there were no significant changes (p≤0.05) in INR level, liver and kidney functions. Treatment of OVX rats with SOE or D for 12 weeks improved both the architecture of bones as shown from the histopathological results and BMs, serum electrolytes and E2 levels (p≤0.05) which approached SC-group. Moreover after treatment of OVX rats with SOE the levels of lipid profile and uric acid were improved and approached SC-group, while liver function became significant lower (p≤0.05) than SC-group. Also there were no significant changes (p≤0.05) in kidney functions and INR of (OVX-SOE), OVX and SC groups. In contrast in (OVX-D) group the levels of lipid profile, liver and kidney functions, uric acid and INR were significantly higher (p≤0.05) than those of OVX and SC groups. The results of this study show that SOE has therapeutic effects on osteoporosis, while it has no adverse effects on lipid profile, uric acid, liver and kidney functions when compared to HRT. SOE offers a promising alternative in the design of new strategies in nutritional management of age-related bone complications.

Clinical characteristics of male osteoporosis

As men are less likely than women to develop osteoporosis, male osteoporosis remains poorly understood. However, elderly men have a clearly reduced bone mineral density and increased risk for fractures. In Japan, one in four patients with osteoporosis is male. Male osteoporosis is associated with not only reduction in androgen, but also estrogen, and differs from postmenopausal osteoporosis in that decreased bone formation is involved and that age-related changes in cortical bone structure and perforation of the trabeculae of cancellous bone are unlikely to occur. The proportion of secondary osteoporosis is higher for men than women;therefore, differential diagnosis is important in the diagnosis of male osteoporosis. In addition, it is recommended that bone mineral density be measured at the femoral neck or total hip in men. Men have a worse prognosis following fractures than women, and management of male osteoporosis is highly important for extending healthy life expectancy.

Клинико-рентгенологическая оценка эффективности лечения апикального периодонтита с применением авторской методики вакуумно-струйной ирригации корневых каналов

A device and techniques for vacuum-bolus irrigation of root canals are developed on the basis of the analysis of existing methods of medical treatment of root canals in endodontic treatment. A comparative assessment of the impact of different variables of vacuum on the degree of cleaning of the root canal model was carried out in an invitro experiment and the optimal values of vacuum and exposure time were pointed out. In the clinical part of the study 52 patients aged from 25 to 44 years with a diagnosis of apical periodontitis were treated and dynamically monitored during one year (the author`s vacuum-bolus technique was applied to 32 patients of the main study group in the course of endodontic irrigation of root canals; while 20 patients of the control group experienced a standard irrigation method with the use of endodontic syringe in the course of endodontic treatment). Criteria of the modified periapical index (PAI) were used to assess the efficacy of treatment. It was found that after 12 months, 90,5 % of patients of the main study group had no signs of demineralization of bone tissue, the orientation of bone trabeculae of cancellous bone and cortical plate were recovering. Thus, the vacuum-boluc irrigation of root canals can help us improve the efficiency of treatment of destructive forms of apical periodontitis.

Bone structure after two sequential regimens of tamoxifen and Arimidex in an ovariectomized rat model

Background Tamoxifen and Arimidex are two standard drugs for endocrinal therapy in breast cancer patients. However, it is not well established as to which of the two drugs should be prescribed first in the sequential regimens. Aim The present study was designed to investigate bone structure characteristics after two alternative sequential regimens of tamoxifen and Arimidex to determine the superior regimen conserving bone in postmenopausal rats. Materials and methods Adult female rats were divided into six groups: group I included control rats; group II included ovariectomized (ovx) nontreated rats; group III included ovx rats treated with tamoxifen; group IV included ovx rats treated with Arimidex; group V included ovx rats treated sequentially with tamoxifen plus Arimidex; and group VI included ovx rats treated sequentially with Arimidex plus tamoxifen (tamoxifen→Arimidex vs. Arimidex→tamoxifen). Daily oral drug treatments were given for 1 month for each drug. Tamoxifen was administered at a dose of 60 μg/day/ rat. Arimidex was administered at a dose of 40 μg/rat/day. At the end of the experiment, all rats were sacrificed, and the tibias were extracted and processed for paraffin block embedding or scanning electron microscopic examination. Cortical and trabecular bone thickness were measured by means of image analysis. Results Histological and scanning electron microscopic observations revealed widening of the haversian canals, with marked loss of cancellous bone trabeculae following ovariectomy. This was confirmed by a significant decrease in bone thickness on histomorphometry. Single drug treatment with Arimidex revealed extensive cavitation and widening of the haversian canals with severe erosion cavities. The tamoxifen-treated group showed apparently preserved bone structure compared with the Arimidex group. Group of the first sequential therapy (group V) demonstrated histologically few cancellous bone trabeculae. However, the second sequential regimen (group VI) showed severe rarefaction, thinning, and bone fractures. Scanning microscopy and bone measurements confirmed the histological findings. Conclusion Sequential hormonal treatment starting with tamoxifen followed by Arimidex is likely to preserve bone structure compared with the other sequential regimen. Single drug treatment with tamoxifen gave best bone preservation. To our knowledge, this is the first experimental report in this regard.

The microstructure of the long bones in rats — descendants gestational stressed mothers under conditions of hypokinesia

High percentage of the children in mothers who received ges­tational stress already at a young age suffer from hypertension, obesity, cardiovascular disease, type II diabetes, i.e. prenatally programmed adult diseases. Wherein it leaves unclear character of stress influence in pregnant women on fetal skeletal formation and characteristics of the microstructure of the bones in offsprings out of such mothers. Objective : To determine the microstructure of bone tissue in female rats whose mothers had subjected to gestational stress in condition of functional rest and under additional stressing by means of hypokinesia. Methods : Modeling of socio-emotional stress in pregnant rats during the first trimester of pregnancy, getting the offsprings in 12 months of age and reproduction of hypokinesia in half of them. We examined femurs using methods of histology. Results : While pathomorphological examination it was found that in offsprings from intact mothers microstructure of егигдфк bones in all their parts was unchanged. In offsprings from stressed mothers in metaphyseal cancellous bone trabeculae there were revealed marked signs of violated osteogenesis and accelerated bone resorption. In the cortex of the femur in these descendants there were found osteons with irregular shape, rem­nants of fragmentary structures, widened channels of osteons. Hypokinesia in descendants of intact mothers did not cause any significant effect on the microstructure of the femur. At the same time after hypokinezia in offspring of stressed mothers there were obsrved signs of destruction as a spongy tissue (trabecular thinning, widening of bone marrow spaces, violation of the trabecular mesh) and compact bone tissue (resorption according to canalicular type, foci of lysis, uneven coloring of matrix). Conclusion: As a result of hypokinesia in the offspring of embrionally stressed mothers structure of the bone tissue violates. They constitute a group of risk on osteopenia developing and require attention to processes of the skeleton formation.

Performance of Non-Cemented, Hemispherical, Rim-Fit, Hydroxyapatite Coated Acetabular Component

The purpose of this study was to assess the durability of a non-cemented, hemispherical rim-fit, hydroxyapatite coated cup with a highly cross-linked polyethylene in 223 total hip arthroplasties. At 6-years follow-up (range, 5–9), there were no cup revisions for osteolysis or loosening. Radiologic evidence of osseointegration was based on presence of Stress Induced Reactive Cancellous Bone and radial trabeculae, seen in 47% and 93% of cups, respectively; both were most prevalent in Zone 1. There was no interference demarcation in any zones. Two cups were revised (0.9%): one for dislocation and another for infection. The Kaplan–Meier survivorship for cup revision for any failure (infection, dislocation) was 99% and for mechanical failure (osteolysis, loosening) was 100%. This design has excellent safety, efficacy and durability.

The Problem of Fracture Fixation Augmentation and Description of a Novel Technique and Implant for Femoral Neck Stabilization

Fracture augmentation for osteopenic bone is a widely accepted concept but not commonly used due to the difficulty with application of the materials in conjunction with surgical implants in fracture repair. Until recently there was little choice of materials for augmentation, but new formulations of structural orthobiological matrix (SOM) have been developed, which have better flow and setting properties than the original polymethylmethacrylate and calcium phosphate ceramics materials. In addition, a new class of injectable implants with the ability to deliver some of these newer SOMs has been designed and received regulatory clearance as fracture fixation devices. This cadaveric study was undertaken to assess the feasibility of using the N-Force Fixation System in a femoral neck fracture model with 6 different SOMs. A new property of SOM was discovered regarding the flow characteristics of the tested materials within the proximal femur. Intrusion and extrusion characteristics were observed and were SOM specific. C-arm fluoroscopy and CT studies revealed the ability of intrusion-type SOM to intrude into cancellous bone trabeculae and minimize the chance of joint extrusion through fracture lines, whereas extrusion-type SOM would not intrude into trabecular spaces and demonstrated a tendency for fracture site extrusion and fracture contact interposition, risking compromise of fracture healing and angiogenesis. The instrumentation and implants gave reproducible implant placement and SOM delivery with low-pressure application and circumferential augmentation from the near cortex extending into the femoral neck and head in a tapering cone-type pattern.

Histological and histometrical studies on the Effects of Fluoride on the Femur in Rats

Background: Fluoride (F ) is a trace element that is incorporated into bone mineral during bone formation. This study assessed the effect of increasing Fluoride doses on the bone formation and microarchi tecture on the Femur of rats by histological, and histometrical methods. Materials and Methods : A total of 16 rats was divided into one group of control and three groups of animals that received 0.2, 0.4, 0.8 mg/kg of Fluoride daily for 3 weeks by gavage. Rats which were exposed to inorganic Fluoride in drinking water produced significantly more levels of bone le sions than the controls. Results : Numerous osteocyte lacunae buried at various dept hs were evident, and the lacunar walls were irregular with mineralized s egments running in all directions. The trabeculae of cancellous bone in th ese animals contained large amounts of osteoid. Conclusion: The results of the present study indicated that th e ingestion of Fluoride affected morphological changes in the Femur of rats.

Role of some phytoestrogens in recovering bone loss: histological results from experimental ovariectomized rat models

Background/aim Osteoporosis is a disease characterized by a decrease in bone mass and is widely recognized as a major health problem. Ovarian hormone deficiency is a major risk factor for osteoporosis. A sharp decrease in ovarian estrogen production is the predominant cause of rapid bone loss and deterioration of bone architecture, resulting in increased bone fragility during the first decade after menopause. Materials and methods A total of 70 albino rats were used, divided into seven groups of 10 rats each. Group 1 was subjected to sham operation and used as a control group. In group 2, rats were ovariectomized (OVX) and used as a model of postmenopausal osteoporosis. Three months after the operation the OVX rats (group 2) were divided into six subgroups: one was considered the positive control group; another one was treated with synthetic estrogen compound; and the other four subgroups were fed a diet containing red clover, fennel, carob, and a combination of the three plants. At the end of the experiment (after 3 months' treatment) the animals were killed, and the femur shafts were extracted, decalcified, and processed into paraffin blocks. Sections were stained with hematoxylin and eosin for histopathological, image analysis, and morphometric studies. Other sections were stained with periodic acid Schiff for histochemical investigations. Results The histopathological results of this study revealed that ovariectomy caused a decrease in thickness of the cortical compact bone in the middle shaft of the femur and of the trabeculae in cancellous bone in the head of the femur bone. Histochemical results showed new bone formation in sections of rats treated with plants. The best results were detected in sections of rats treated with a combination of the three plants. Red clover, fennel, and carob individually or combined have a better ameliorating effect on ovariectomy-induced osteoporosis than does synthetic estrogen compound. Conclusion Treatment of OVX rats with phytoestrogens such as red clover, fennel, and carob might improve the histopathological and histochemical changes and morphometric parameters in bone with ovariectomy-induced osteoporosis.