BACKGROUND:Nanosilver has significant antibacterial properties, and nanohydroxyapatite has good biological activity and mechanical strength, while their mixture cannot only promote bone formation but also have antibacterial properties. OBJECTIVE:To observe the effect of nanosilver and nanohydroxyapatite mixed filing on the osseointegration of immediate implants. METHODS: Nine New Zealand white rabbits were randomly divided into experimental group (n=6) and control group (n=3) after four incisors from the upper and lower jaw were extracted. The mixture of nanosilver and nanohydroxyapatite was filed into the tooth socket in the experimental group, while nanohydroxyapatite was filed into the tooth socket in the control group. Titanium screw was immediately implanted into both groups. The intact maxila and mandibular specimens were harvested at the 4th, 8th, and 12th weeks after operation. Gross observation, X-ray bone density analysis, torque test and histological observation were conducted. RESULTS AND CONCLUSION:The gray value and maximum torque value of regenerated osseous tissue at different time points in experimental group were significantly higher than those in the control group (P < 0.05). Within 12 weeks of implantation, the bone formation rate and maturity of new bone tissue were higher in the experimental group compared with the control group, and no inflammatory cel infiltration occurred. At the 4th week after implantation, there was a large amount of inflammatory cel infiltration, and few inflammatory existed at the 8th week after implantation. These results demonstrate that compared with nanohydroxyapatite alone, the mixture of nanosilver and nanohydroxyapatite shows better antibacterial effect, biocompatibility and osteoinductive ability, which may accelerate osseointegration and promote osteogenesis.

BACKGROUND: Based on a mouse model of tibial implantation, some scholars have found that the CaP-coated implant with recombinant human parathyroid hormone (1-34) (PTH(1-34)) shows strong osteogenesis effect at early stage, but this coating has not been applied in the oral environment.OBJECTIVE: To explore the role of local application of PTH(1-34) on immediate implant osseointegration . METHODS: Nine New Zealand white rabbits were randomly divided into two groups (six in experimental group and three in control group). All of the tooth sockets were filled with heterogeneous freeze-dried bone firstly after four incisors of each rabbit were extracted. In the experimental group, a titanium screw with PTH(1-34) loaded CaP coating was implanted into each tooth socket, while in the control group, a titanium screw with only CaP coating was implanted. The animals were executed respectively at 4, 8, 12 weeks after operation, and the intact maxillary and mandibular specimens were harvested and tested by gross observation, bone density analysis, torque test, histologic al observation, X-ray observation.RESULTS AND CONCLUSION: The gray value and maximum torque value of regenerated osseous tissue at different time points in the experimental group were significantly higher than those in the control group (P < 0.05). Within 4-12 weeks after implantation, regenerated and mature bone tissue appeared earlier in the experimental group than the control group. A large amount of new blood vessels were seen in the experimental group at 8 weeks after implantation, while in the control group, there were only few new blood vessels. To conclude, the local application of PTH(1-34) can promote bone formation, improve the implant-bone bonding strength, and enhance the stability of the implant.

BACKGROUND: Some studies have shown that topical application of zoledronic acid and topical application of silver nanoparticles can promote bone formation, but the difference between two methods has not been reported. OBJECTIVE: To investigate the effect of topical application of zoledronic acid versus topical application of silver nanoparticles on rabbit tooth extraction socket immediate implantation of titanium screw bonding. METHODS: Twenty-four New Zealand white rabbits were randomly divided into zoledronic acid and silver nanoparticles groups (n=12/group). After removing four incisors of the upper and lower jaws, the mixture of nanometer silver and nanometer hydroxyapatite and nanometer zoledronic acid hydroxyapatite were respectively filled in the tooth extraction pit of the two groups, and titanium screw was implanted at the same time. The isolated specimens of the upper and lower mandibles were taken at 4, 8 and 12 weeks after surgery. The data reflecting the osseointegration around the implant were obtained through gross observation, torque test, bone density test and histomorphological observation. The study was approved by the Ethical Committee of the Third Hospital of Hebei Medical University in December 2015, approval No. Z2015-021-1. RESULTS AND CONCLUSION: (1) The test results of torque mechanics showed that the average torque peak value of all titanium nails increased with the extension of time (the average value of torque peak value) and reached the maximum value at 12 weeks (the average value of torque peak value). At 4, 8 and 12 weeks after surgery, the torque peak value of titanium screw in the zoledronic acid group was higher than that in the silver nanoparticles group, and the stability of titanium screw in zoledronic acid group was better than that in silver nanoparticles group, but the difference was insignificant (P>0.05). (2) General observation and histological observation showed that at 4, 8 and 12 weeks after surgery, the hardness and structure of bone around the implants in the zoledronic acid group were significantly better than those in the silver nanoparticles group. (3) Bone mineral density analysis results showed that, at 4, 8 and 12 weeks after surgery, the gray value of bone tissue around the titanium screw in the zoledronic acid group was higher than that in the silver nanoparticles group at the same period (P>0.05). (4) These results suggest that the osseointegration of immediate implantation using nanometer zoledronic acid hydroxyapatite is better than that of the mixture of nanometer silver and nanometer hydroxyapatite.

ObjectiveTo compare the clinical effect of percutaneous iliosacral screws osteosynthesis (PISO) and open reduction internal reconstruction plate fixation in treating unstable pelvic fractures combined with sacroiliac joint dislocation,and evaluate their safety and practicality.MethodsFrom March 2004 to October 2010,37 patients with vertical unstable pelvic fractures were admitted to our department.Twenty cases were treated with percutaneous sacroiliac screw fixation and 17 cases were performed opened reduction and internal reconstruction plate fixation under C-arm X-ray's guide.The perioperative parameters and postoperative imaging indexes were compared and analyzed.ResultsAll patients were followed up for 6 months to 26 months,with an average of 15 months.There were statistical significances between the PISO group and open reduction internal fixation group in operation time,blood loss,postoperative pain,mean fever time and hospital stay.The two groups showed no significant difference on postoperative X-evaluation of reduction effect.The average healing time was 3.2 months and the difference was not statistically significant between two groups.PISO group had no complications such as infection,bent nails or broken nails.ConclusionThrough compared and analyzed the two groups in treating unstable pelvic fractures,the percutaneous sacroiliac screw fixation has been proved for a kind of ideal minimally invasive surgery method because of locating exactly,less damage and blood loss,milder pain and quicker recovery.But it demands higher operation techniques.Adequate preoperative preparation and postoperative patients' cooperation can reduce complications incidence.The second group of anterior reconstruction plate or T-shape plate to fix vertically unstable pelvic fractures at same time shows a good result of stabilization.

OBJECTIVETo investigate the crystallographic properties of the mineral phases of normal enamel and dentin (dental apatite) in deciduous and permanent teeth.

METHODSThree kinds of physical methods including X-ray diffraction (XRD), infrared absorption spectroscope (IR) and electron probe micro-analysis (EPMA) were utilized in this study.

RESULTSDental apatite was not uniphase, but multiphase, which could be described as carbonate-substituted hydroxyapatite. Compared to dentin apatite, the higher crystallinity and expanded a-axis lattice parameters were found in enamel. Chemical analyses demonstrated that higher concentrations of Mg and CO(3)(2-) were found in dentin than those of enamel. But enamel had higher Cl content.

CONCLUSIONSThe differences among enamel and dentin, in terms of lattice parameter and crystallinity may be partially attributed to the incorporation of Mg, CO(3)(2-) and Cl minor elements.

Dental Enamel ; chemistry ; Dentin ; chemistry ; Electron Probe Microanalysis ; methods ; Humans ; Spectrophotometry, Infrared ; methods ; Tooth ; chemistry ; X-Ray Diffraction ; methods

The subtype H9N2 avian influenza virus greatly threatens the Chinese poultry industry, even with annual vaccination. Waterfowl can be asymptomatically infected with the H9N2 virus. In this study, three H9N2 virus strains, designated A/Goose/Jiangsu/YZ527/2011 (H9N2, Gs/JS/YZ527/11), A/Goose/Jiangsu/SQ119/2012 (H9N2, Gs/JS/SQ119/12), and A/Goose/Jiangsu/JD564/2012 (H9N2, Gs/JS/JD564/12), were isolated from domestic geese. Molecular characterization of the three isolates showed that the Gs/JS/YZ527/11 virus is a double-reassortant virus, combining genes of A/Quail/Hong Kong/G1/97 (H9N2, G1/97)-like and A/Chicken/Shanghai/F/98 (H9N2, F/98)-like; the Gs/JS/SQ119/12 virus is a triple-reassortant virus combining genes of G1/97-like, F/98-like, and A/Duck/Shantou/163/2004 (H9N2, ST/163/04)-like. The sequences of Gs/JS/JD564/12 share high homology with those of the F/98 virus, except for the neuraminidase gene, whereas the internal genes of Gs/JS/YZ527/11 and Gs/JS/SQ119/12 are closely related to those of the H7N9 viruses. An infectivity analysis of the three isolates showed that Gs/JS/SQ119/12 and Gs/JS/YZ527/11 replicated well, with seroconversion, in geese and chickens, the Gs/JS/JD564/12 did not infect well in geese or chickens, and the F/98 virus only infected chickens, with seroconversion. Emergence of these new reassortant H9N2 avian influenza viruses indicates that these viruses can infect both chicken and goose and can produce different types of lesions in each species.
Animals ; Asian Continental Ancestry Group ; Chickens ; Geese ; Humans ; Influenza A Virus, H7N9 Subtype ; Influenza A Virus, H9N2 Subtype ; Influenza in Birds ; Neuraminidase ; Population Characteristics ; Poultry ; Sequence Analysis ; Seroconversion ; Vaccination

Objective:To compare the alveolar cortical bone density and thickness of jaw bones between teenagers (12-18 years of age) and adults(19-48 years of age).Methods:Spiral computed tomographic images of 60 cases were obtained from the subjects with the ages of 12 to 48 years(27 Males and 33 females,35 teenagers and 25 adults).Buccal cortical bone thickness and density in Hounsfield units were measured at 12 interradicular sites and to a depth of 14 mm.Results:The alveolar cortical bone thicknesses and densities of the jaw bones significantly increased from the crest to base of alveolar crest.The average cortical bone thicknesses rangedfrom 1.0 to 1.5 mm in the anterior part of the jaw bones,1.1 to 1.8 mm in maxillary posterior area and 1.5 to 2.8 mm in the mandible posterior areas.The cortical bone thickness and density were greater in the mandible than in the maxilla(P ＜ 0.05).The thickness values did not show difference between males and females,between adolescents and adults.Higher values of bone density were found in the adults than in the teenagers(P ＜0.05).The highest bone density in the mandible posterior area of adults was observed,and the lowest bone density in the maxillary posterior area of adolescents.Conclusion:Alveolar cortical bone density of adolescents is lower than that of adults,especially in the maxilla posterior region.

BACKGROUND:The type of graft selected during anterior cruciate ligament revision is considered one of the main factors affecting the postoperative outcome,but there are few reports on the comparison between different graft materials. OBJECTIVE:To explore the medium-to-long-term clinical efficacy after anterior cruciate ligament revision with autologous ligament,allogeneic ligament,and LARS artificial ligament. METHODS:A total of 67 patients with the first anterior cruciate ligament revision admitted to the Department of Joint and Sports Medicine,The Second Hospital of Tangshan from May 2011 to May 2020 were selected,including 41 males and 26 females,with a mean age of(45.83±7.39)years.They were divided into three groups according to different grafts used:autologous ligament group(n=24),allogeneic ligament group(n=22),and LARS artificial ligament group(n=21).Follow-up for more than 36 months after revision was performed to evaluate the effect of revision. RESULTS AND CONCLUSION:(1)International Knee Documentation Committee(IKDC)score,Lysholm knee score,and Tegner motor score 1 year after surgery and at the last follow-up in the three groups were higher than those before surgery(P<0.05).There were no significant differences in IKDC score,Lysholm knee score,and Tegner motor score among the three groups 1 year after surgery and the last follow-up(P>0.05).(2)The lateral differences of KT-1000 at 1 year after surgery and the last follow-up among the three groups were lower than those before surgery(P<0.05).The lateral difference of KT-1000 and the positive rate of the axial shift test in the last follow-up of the LARS artificial ligament group were higher than those in the autologous ligament group and allogeneic ligament group(P<0.05).(3)At the last follow-up,X-ray films showed no obvious enlargement of the reconstructed bone tunnel and no obvious failure of the graft fixation device.There was no obvious aggravation of osteoarthritis,but bone density decreased significantly in some elderly patients.(4)These findings suggest that anterior cruciate ligament revision with LARS artificial ligaments can obtain good initial stability,but with the extension of time,the stability of partial cases tends to decrease,even with reconstructed ligament failure.Both allogeneic and autogenous ligaments can obtain good clinical efficacy in anterior cruciate ligament revision.

Objective To describe the demographic and clinical characteristics of patients with the diagnosis of multiple myeloma(MM)and to analyse the outcome of difierent regimens for the treatment of MM.Methods The study reviewed 332 MM cases diagnosed within the period from January 1,2002 to December 31,2002.These patients were tracked via their records to a total period of three years.Results First-line treatment:Totally 332 patients were included,among them 325(97.9%)patients received chemotherapy and 7(2.1%)patients received stem cell transplantation(SCT);Second-line treatment:197 patients were included,among them 190(96.5%)patients received chemotherapy and 7(3.6%)patients received SCT;Third-line treatment:92 patients were included,among them 88(95.7%)patients received chemotherapy and 4(4.4%)patients received SCT.Major adverse effects were follows:severe infection 19.3%,severe anaemia 19.3%,phlebothrombosis 1.2%,thrombocytopenia 16.9%,fever associated with neutropenia 18.1%.Conclusions Some curative effects can be achieved by using traditional treatment plans to treat patients suffering from MM,but new methods are expected to improve the prognosis.