Alveolar bone reconstruction simulation is an effective means for quantifying orthodontics, but currently, it is not possible to directly obtain human alveolar bone material models for simulation. This study introduces a prediction method for the equivalent shear modulus of three-dimensional random porous materials, integrating the first-order Ogden hyperelastic model to construct a computed tomography (CT) based porous hyperelastic Ogden model (CT-PHO) for human alveolar bone. Model parameters are derived by combining results from micro-CT, nanoindentation experiments, and uniaxial compression tests. Compared to previous predictive models, the CT-PHO model shows a lower root mean square error (RMSE) under all bone density conditions. Simulation results using the CT-PHO model parameters in uniaxial compression experiments demonstrate more accurate prediction of the mechanical behavior of alveolar bone under compression. Further prediction and validation with different individual human alveolar bone samples yield accurate results, confirming the generality of the CT-PHO model. The study suggests that the CT-PHO model proposed in this paper can estimate the material properties of human alveolar bone and may eventually be used for bone reconstruction simulations to guide clinical treatment.
To observe the effect of pulsed electromagnetic fields (PEMFs) of different treatment time on bone mineral density of femur in ovariectomized rats, so as to find out the treatment time for the best therapeutic efficacy. Methods Fifty female SD rats were randomly divided into 5 groups: sham-ovariectomized (SHAM) group (no PEMFs treatment), ovariectomy (OVX) control group (no PEMFs treatment), OVX I, II and III groups (PEMFs treatment at 8 Hz frequency with 3. 8 ×10-10A/m intensity 20, 40, and 60 minutes daily for 30 days, respectively). All rats were given bilateral ovariectomy except those in the SHAM control group. Bone mineral density (BMD) of femur was assessed at 30 days after PEMFs treatment. Results In OVX control group, hypotrichosis, hypoactivity and l istlessness were observed after operation; and in SHAM group, OVX I group, OVX II group and OVX III group, pilus, psyche and activity were normal. The BMD values were (0.226 ± 0.011), (0.210 ± 0.011), (0.231 ± 0.013), (0.231 ± 0.017) and (0.229 ± 0.013) g/cm2 in SHAM group, OVX control group, OVX I group, OVX II group and OVX III group respectively, showing significant differences between OVX control group and other groups (P lt; 0.05), but showing no significant differences between other 4 groups (P gt; 0.05). Conclusion P EMFs of the three different treatment times can maintain the BMD in ovariectomized rats. It shows that PEMFs have the same effect of maintaining BMD with increasing of treatment time at the range of 20-60 minutes in ovariectomized rats.
ObjectiveTo compare the clinical effects of pulsed electromagnetic fields (PEMFs) with oral alendronate in the treatment of postmenopausal osteoporosis. MethodsFourty patients diagnosed to have postmenopausal osteoporosis (OP) from September 2009 to September 2010 were included in our study. They were randomly divided into the experimental group and the control group. All patients were administered the same basic drugs:Caltrate 600 mg and Alfacalcidol 0.5 μg per day. For the experimental group, PEMFs were offered 6 times per week for 5 weeks (30 times in total), and patients in this group were followed up for 12 weeks. For the control group, alendronate was given at a dose of 70 mg per week for 12 weeks. Bone mineral density (BMD), visual analogue scale, and manual muscle testing (MMT) scale were evaluated before, 1 week, 5 weeks, and 12 weeks after intervention. ResultsIncreasing of BMD, pain relieving, and improvement of MMT had a trend of increasing values after 5 weeks of treatment in the experimental group (P<0.05), but there was no significant difference between the two groups (P>0.05). However, there was a significant difference between the two groups in patients' lower back muscle strength after treatment (P<0.05). ConclusionPEMFs have the same effect as alendronate in pain relief, and bone mass and muscle strength improvement, and are even advantageous in increasing back muscle strength compared with alendronate.
ObjectiveTo analyze the relationship between the bone mineral density (BMD) and lumbar intervertebral disc degeneration in rhesus macaques by using T1ρ-MRI. MethodsTwenty female rhesus macaques at the age of 10.9 years on average (rang, 4-20 years) were selected. The lumbar intervertebral discs were classified by Pfirrmann grading system and the T1ρ relaxation time (T1ρ value) was examined by using MRI (Philips 1.5 Tesla), and then BMD values of the L4,5 vertebrae and femoral ward's triangle were detected by using Osteocore dual energy X-ray absorptiometry. Finally, the relationship of T1ρ value of the lumbar intervertebral discs and Pfirrmann grading with age, weight, BMD of lumbar vertebrae and femoral ward's triangle was analyzed. ResultsThe BMD values of lumbar vertebrae and femoral ward's triangle were (0.64±0.17) g/cm2 and (0.67±0.19) g/cm2 respectively, showing no significant difference (t=2.893, P=0.128). According to Pfirrmann grading system, there were 7 cases of grade I, 8 cases of grade Ⅱ, and 5 cases of grade Ⅲ at L4,5 intervertebral discs. The T1ρ value of the lumbar intervertebral disc was (104.08±18.65) ms; the T1ρ values of grades I, Ⅱ, and Ⅲ were (121.31±13.44), (104.73±15.01), and (77.41±11.87) ms, respectively. There was a negative correlation between T1ρ value and the age and the BMD of lumbar vertebrae and femoral ward's triangle. There was a positive correlation between Pfirrmann grading and the variables as listed above. Significant negative linear correlation was also observed between T1ρ value and Pfirrmann grading. ConclusionThe T1ρ value is a reliable index when quantifying lumbar intervertebral disc degeneration, and there is a significant positive correlation between BMD and lumbar intervertebral disc degeneration in rhesus macaques.
ObjectivesTo systematically review the influence of antiepileptic drugs on bone mineral density and bone metabolism in adults.MethodsPubMed, EMbase, CNKI, CBM, VIP and WanFang Data databases were electronically searched to collect studies on the influence on antiepileptic drugs on the bone mineral density and bone metabolism in adults from inception to April 1st, 2018. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 14 studies were included. The results of meta-analysis showed that: VPA could decline the bone mineral density of lumbar spine (SMD=–0.39, 95%CI –0.65 to –0.13, P=0.003); CBZ (SMD=–0.71, 95%CI –1.08 to –0.33, P=0.000 2) and VPA (SMD=–0.3, 95%CI –0.58 to –0.02, P=0.03) could decline the bone mineral density of femoral neck; CBZ could decline the bone mineral density of total hip (SMD=–0.47, 95%CI –0.84 to –0.10, P=0.01). Serum 25-hydroxy vitamin D3 was decreased in OXC group (SMD=–0.67, 95%CI –1.28 to –0.05, P=0.03); serum calcium was decreased in CBZ (SMD=–0.49, 95%CI –0.78 to –0.20, P=0.000 8), LEV (SMD=–0.83, 95%CI –1.15 to –0.51, P<0.000 01) and OXC (SMD=–0.48, 95%CI –0.90 to –0.05, P=0.03) group; serum phosphorus was decreased in LEV group (SMD=–11.36, 95%CI –12.97 to –9.76, P<0.000 01). Serum alkaline phosphatase was increased significantly in LEV (SMD=6.79, 95%CI 5.78 to 7.80, P<0.000 01) and CBZ (SMD=1.90, 95%CI 1.35 to 2.44, P<0.000 01) group.ConclusionsCurrent evidence shows that treatment with antiepileptic drugs may be associated with an decreasing bone mineral density and influence bone metabolism in epileptic adults. Due to limited quality and quantity of the included studies, more high quality studies are required to verify above conclusion.
Objective To explore the significance and the relationshi p between osteoporosis and the mRNA expressions of vascular endothel ial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2) in nontraumatic avascular necrosis of the femoral head (NONFH), so as to provide a theoretical basis for the pathogenesis and the cl inical treatment of NONFH. Methods Sixty-nine specimens of femoral head were collected from voluntary donators undergoing total hi p arthroplasty, including 37 cases of NONFH (NONFH group) and 32 cases of fresh femoral neck fracture (control group). In NONFH group, there were 26 males and 11 females with an average age of 57.3 years (range, 43-75 years), including 19 cases of steroid-induced avascular necrosis of the femoral head (ANFH), 16 cases of alcohol ic ANFH, and 2 cases of idiopathicANFH; according to Ficat staging system, there were 23 cases at stage III and 14 cases at stage IV. In control group, there were 23 males and 9 females with an average age of 58.6 years (range, 46-79 years). The NO level of serum, the Q value of femur, and the bone mineral density (BMD) of weight-bearing area were measured firstly. The bone tissues were harvested from weightbearing necrosis area and healthy area. The pathological change was observed by HE staining, the percentage of empty bone lacuna and the percentage of trabecular bone area were calculated. The mRNA expressions of VEGF and BMP-2 in femoral head were detected through in situ hybridization technique. Results There were significant differences (P lt; 0.05) in the NO level of serum, the Q value of femur, and the BMD between NONFH group and control group. In NONFH group, the femoral head showed irregular shape, the articular cartilage exfol iated and collapsed. In weight-bearing necrosis area, the bone trabeculae were sparse and non-intact with a great number of empty lacuna; necrotic bone trabeculae were decomposed and absorbed; no obvious bone regeneration and repair were observed. In weight-bearing healthy area, the fat cells in bone marrow showed prol iferation and hypertrophy. In control group, the femoral head had normal appearance, intact articular cartilage, and intact bone trabeculae with a regular arrange, and osteocytes were clearly seen. There were significant differences in the percentage of empty bone lacuna and the percentage of trabecular bone area between NONFH group and control group (P lt; 0.05). The mRNA expressions of VEGF and BMP-2 were positive in 2 groups. The positive area ratio, the absorbance value, and integral absorbancevalue of VEGF mRNA and BMP-2 mRNA in NONFH group were significantly lower than those in control group (P lt; 0.05);the grey scales of VEGF mRNA and BMP-2 mRNA in NONFH group were significantly higher than that in control group (P lt;0.05). Conclusion The pathological stage of osteoporosis may play an important role in the mechanism of the NONFH. The decrease of mRNA expressions of VEGF and BMP-2 in femoral head of NONFH is important reason that affect its bone mass, osteoporosis, rehabil itation, and reconstruction. It may be benefit to the reparative process of the necrosis femoral head to increase the mRNA expressions of VEGF and BMP-2 in the femoral head.
ObjectiveTo evaluate the incidence of osteoporosis and relevant factors in the elderly male patients with chronic obstructive pulmonary disease(COPD).Methods Forty elderly male patients with COPD were enrolled and thirty age-matched healthy subjectss were enrolled.The BMD of lumbar vertebrae and proximal end of the femur were measured by dual energy X-ray absorptiometry.Serum levels of osteocalcin (BGP)and lung function were measured while blood-gas analysis of arterial blood was conducted.Results The BMD of lumbar vertebrae and proximal end of the femur(including lumbar 1 to 4,femoral neck,wards triangle,trochanter and shaft) in the COPD group were significantly lower than those in the control subjects(all Plt;0.01).Serum BGP level in the COPD group was higher than that in the control group[(5.67±1.59)ng/mL vs (4.37±1.47)ng/mL,Plt;0.01).The prevalence of osteoporosis among the COPD patients was significantly higher than that among the control subjects(65% vs 40%,50% vs 20%,both Plt;0.05).BMD in the COPD patients who had a history of smoking was significantly lower than those who did not smoke cigarettes(Plt;0.01 or Plt;0.05).BMD in the COPD patients treated with glucocorticoid were significantly lower than those who were not receiving glucocorticoid therapy(Plt;0.01 or Plt;0.05).BMD was positively correlated with PaO2,BMI,FEV1%pred and FEV1/FVC(Plt;0.01 or Plt;0.05).Conclusions Compared with age-matched normal controls,BMD in elderly male COPD patients are significantly lower with increased osteoporosis risk.Osteoporosis induced by COPD is high change-over pattern. BMD in patients with COPD may be correlated with hypoxia,lung function,smoking,low body mass index and glucocorticoids therapy.
This study aims to investigate the therapeutic efficacy of 50 Hz-0.6 mT low-frequency pulsed electromagnetic field (PEMF) on postmenopausal osteoporosis in ovariectomized rats. Thirty 3-month-old female SD rats were selected and divided into a sham operation group (Sham), an ovariectomized model group (OVX), and a low-frequency pulsed electromagnetic field (PEMF) treatment group, with 10 rats in each group. After 8 weeks, the whole-body bone mineral density (BMD) of each group of rats was measured. The treatment group began to receive PEMF stimulation for 90 minutes daily, while the OVX group only received a simulated placement without electricity. After 6 weeks of intervention, all rats were sacrificed and tested for in vitro BMD, micro-CT, biomechanics, serum biochemical indicators, and bone tissue-related proteins. The results showed that the BMD of the OVX group was significantly lower than that of the Sham group 8 weeks after surgery, indicating successful modeling. After 6 weeks of treatment, compared with the OVX group, the PEMF group exhibited significantly increased BMD in the whole body, femur, and vertebral bodies. Micro-CT analysis results showed improved bone microstructure, significantly increased maximum load and bending strength of the femur, elevated levels of serum bone formation markers, and increased expression of osteogenic-related proteins. In conclusion, this study demonstrates that daily 90-minute exposure to 50 Hz-0.6 mT PEMF effectively enhances BMD, improves bone biomechanical properties, optimizes bone microstructure, stimulates bone formation, and inhibits bone resorption in ovariectomized rats, highlighting its therapeutic potential for postmenopausal osteoporosis.
Objective To ananlyze the relationship between bone mineral density and sex hormone in male patients with obstructive sleep apnea hypopnea syndrome (OSAHS). Methods The study recruited 88 male patients with OSAHS aged 45-60 years in our hospital from October 2014 to October 2016 as an OSAHS group, and 30 healthy subjects without OSAHS as a control group. The general information and PSG parameters were recorded, the bone metabolic markers and bone mineral density of lumbar spine 1-4 (L1-4) and femoral neck (Neck) were measured, and the expressions of serum sex hormone (E2, P, T, FSH, LH and PRL) were determined by chemical luminescence immunity analyzer. The differences in above indexes between two groups and their correlation with bone mineral density were analyzed. Results Smoking rate, drinking rate, neck circumference and body mass index (BMI) of the OSAHS group were significantly higher than those of the control group. Compared with the control group, beta crosslaps (β-CTX, a bone metabolic marker) was significantly higher [(0.53±0.14) ng/ml vs. (0.47±0.15) ng/ml], the bone mineral density of L1-4 and Neck was significantly lower [(0.92±0.12) g/cm2 vs. (1.08±0.08) g/cm2, (0.91±0.11) g/cm2 vs. (1.06±0.13) g/cm2], and the serum testosterone was significantly lower in the OSAHS group [(267.32±89.56) ng/dlvs. (315.68±78.49) ng/dl] (all P<0.05). The result of Pearson correlation analysis showed that apnea hypopnea index (AHI) was negatively correlated with bone mineral density of L1-4 and Neck (bothP<0.001), lowest oxygen saturation (LSaO2) and testosterone were positively correlated with bone mineral density of L1-4 and Neck (all P<0.01). Conclusions The risk of suffering from osteoporosis is higher in male OSAHS patients and it is closely related to the degree of hypoxia. The decrease of testosterone may be one of the mechanisms.
ObjectiveTo explore the effects of pilose antler blood wine on bone mineral density and T-lymphocyte subsets of ovariectomized female Sprague Dawley (SD) rats. MethodsSixty female SD rats were randomly divided into six groups:normal control group, osteoporosis model group, pure ethylalcohol group, high dose of pilose antler blood wine group, medium dose of pilose antler blood wine group and low dose of pilose antler blood wine group. Normal control group and osteoporosis model group were given saline with the dose of 9.1 g/(kg·d). Pure ethylalcohol group was given pure ethylalcohol with the dose of 9.1 g/(kg·d). The doses of pilose antler blood wine were 4.5, 9.1 and 13.6 g/(kg·d) respectively in low, medium and high dose of pilose antler blood wine group. After the feeding of pilose antler blood wine for 30 days, the bone mineral density and T-lymphocyte subsets of rats were assessed. ResultsThe difference in bone mineral density among the three pilose antler blood wine groups was significant (P<0.05); the most obvious improvement of one mineral density was found in low and medium dose of pilose antler blood wine groups (P<0.05). The CD4+ T cells and CD4+/CD8+ significantly increased and CD8+ T cells proportion decreased significantly in pilose antler blood wine group compared with those in the osteoporosis model group (P<0.05). CD4+ T cells in medium dose group increased obviously compared with that in the high dose group (P<0.05). CD4+/CD8+ in low and medium dose groups obviously increased compared with that in high dose group (P<0.05). CD4+ T cells of medium dose group obviously increased compared with that in pure ethylalcohol group (P<0.05). CD8+ T cells in medium and low dose groups obviously decreased compared that in pure ethylalcohol group (P<0.05). CD4+/CD8+ in the three dose groups increased significantly compared with that in pure ethylalcohol group (P<0.05). ConclusionTree different doses of pilose antler blood wine could prevent the osteoporosis and improve the immune function. The effects of medium and low dose of groups were more obvious.