0.05). Conclusion:Ti-29Nb-13Ta-4.6Zr alloy is histocompatible.

Objective:To study the effects of receptor activator of nuclear factor-kB ligand-RANKL in osteoblasts (OBs) activiated by Porphyromonas endodontalis(Pe),and to investigate the bone resorptive pathogenesis induced by Pe.Methods:Primary rat calvarial osteoblasts were cultured, then were infected with Pe ATCC 35406 at the density of 107 and 109 CFU/ml respectively for 24 h.To determine the kinetic effect of Pe on OBs,107 CFU/ml of Pe was used to stimulate the cells for 0,6,12,18 and 24 h respectively, RT-PCR were used to examine the RANKL mRNA expression.Results:The grey level ratio of RANKL mRNA expression to ?-actin in untreated OBs was 0.32,that in the cells infected by 107 and 109 CFU/ml of Pe for 24 h was increased to 1.73 and 2.24 respectively.Infected by 107 CFU/ml of Pe for 6,12 and 18 h,the ratio was 0.93,2.01 and 1.97 respectively.Conclusion:Pe may stimulate RANKL expresson in osteoblasts.

Objective To study the adverse effects on periodontal tissues caused by crownless roots in elderly people with osteoporosis. Methods Totally 60 12?week SD rats(30 male and 30 female)were randomly divided into the control group(10 male and 10 female sham?operated rats)and the osteoporosis group(20 male and 20 female castrated rats). After 12 weeks,the bone mineral density of right femora was measured by dual energy X?ray for all rats to confirm osteoporosis. The right molar crown was pinched off with haemostatic forceps and the molar root was retained. The 10 con?trol rats and the 20 experimental rats were sacrificed respectively at postoperative 2 and 4 weeks. The periodontal tissues of right molar were sampled and the morphology of the parodontium and the alveolar bone was observed by haematoxylin and eosin(HE)staining and the expression of tumour necrosis factor?alpha(TNF?α)and inducible nitric oxide synthase?2(NOS2)was detected by immunohistochemical staining and real time fluores?cent quantitative PCR(qRT?PCR). Results The HE slices indicated that the periodontal tissues in the osteoporosis group were significantly im?paired compared to the control group as the structure of parodontium loosened. Bone impairment aggravated over time. TNF?αstaining showed as a few claybank spots on the parodontium in the control group,while the staining colour was darkened in the osteoporosis group. The expression of TNF?αmRNA was significantly higher in the osteoporosis group than in the control group(P<0.05). The result of NOS2 was contrary to that of TNF?α. The differences in TNF?αand NOS2 were not statistically significant at 2 and 4 weeks(P>0.05). Conclusion The crownless roots in rats with os?teoporosis cause adverse effects of periodontal tissues as the roots accelerate absorption of the surrounding alveolar tissues. It is indicated that crown?less roots in elderly people with osteoporosis should be removed as soon as possible.

Objective To understand the mental status of 180 stomatology graduates(including undergraduates,masters and PhD students)in China Medical University,whom are hunting job in 2016. Methods A total of 180 stomatology graduates were tested by SCL?90 symptom check?list and self?questionnaire. Results Compared with the national norm,4 factors of SCL?90 in stomatology graduates shows significant differences (P<0.05),they were obsessive?compulsive symptoms,depression,anxiety and paranoid. Chi?square test showed that the 4 factors of masters and doctoral graduate students were significantly higher than undergraduates(P<0.05),and there was no difference between the former two(P>0.05). Multivariate logistic regression analysis showed that family economic conditions were positively correlated with postgraduate examinations;their will?ing to work in stomatology hospitals were closely related to anxiety,depression and other negative emotions. Statistical techniques with univariate re?gression analyses indicated that households’financial status,whether to study for graduate student and doctoral student further,job object for stoma?tological hospital,dental clinic,or department of stomatology in general hospital may be risk factors. Conclusion There are various degrees of men?tal health problems in stomatology graduates of 2016. We should actively guide them,and strengthen their mental health education.

Objective:To study the effects of hydroxyapatite(HA) coating on sandblasted and acid-etched(SLA) surface of titanium dental implants(HA-SLA-Ti) on the biologic characteristics of marrow-origin osteoblasts(MOOBs).Methods:Coating of HA on the SLA surface of titanium dental implants were formed by ion beam assisted deposition (IBAD) method. MOOBs,cultured in vitro,were seeded onto the surface of HA-SLA-Ti and SLA-Ti respectively, the growth of MOOBs on the two kinds of samples were observed by scaning electron microscope.The proliferation index, alkaline phosphatase(AKP) activity, osteocalcin(BGP) content of MOOBs and mRNA relative expression level of osteopontin(opn) were examined and compared between two groups.Results: MOOBs grew well on the surface of HA-SLA-Ti; the proliferation index, AKP activity and BGP content of MOOBs were higher in HA-SLA-Ti group than those in SLA-Ti group(P

Objective To analyse the prognostic value of serumal copeptin in patients with acute exacerbation of COPD compli-cated withrespiratory failure.Methods The serumal copeptin were detected in 60 hospitalized AECOPD patients before and after the treatment and in 30 healthy controls.Results Comparing with control groups,the serumal levels was significantly elevated in the patient with AECOPD before thetreatment and declinied two months later(P <0.05).The level of serum copeptin wereincreasing with the increase in the severity of the disease in acertain extent;The serumalcopeptin were positively correlated with lung function and CAT (r=0.058 and 0.821,P =0.00)and were negativelycorrelated with 6MWD(r=-0.652,P =0.00).Conclusion Serum copeptin could as-sess the incidence of acute exacerbations ofchronic obstructive pulmonary disease and its therapeutic effect;Serum copeptin can reflect the se-verity of AECOPD patients in a certain extent,and has certain clinical value to evaluate the quality of life in patients.

Objective; To evaluate the effects of gingival shade guide in visual shade-matching in vitro models. Methods; 42 tabs of Shofu NCC shade guide were adopted for color measuring. Each tab was fixed in the middle of Gingiva-Indicator, Guray(1,2,3,4) respectively and located in a black box. The measurements were made using the Shadepilot instrument. The color parameters ( CIE1976L * a * b * ) of cervical, body, incisal area of each tab were recorded. The color difference A E value in the same position of each tab was calculated between non-gingival shade guide group and Gumyl ,2,3,4 groups with Shadepilot software. Results; The AE value in the same position of 42 tabs between non-gingival shade guide group and 4 gingival shade guide groups were; cervical (2.93±0.79)NBS,body(0.51±0.27)NBS and incisal(0.61 ±0.29)NBS. In the cervical, body and incisal area, there was no statistically difference among Gumyl ,2,3,4 groups on affecting shade of tabs(P >0. 05). Conclusion; The gingival color has an effect on the cervical shade of tabs, and it can be recognized by human eyes, while gingival color has little effect on the shade of body and incisal area.

BACKGROUND:Selection of proper bone transplantation materials to substitute autogenous bone for treatment of jaw bone defect in patients has become the focus of current researches.OBJECTIVE:To observe the ability of tissue engineered bone constructed with nano-hydroxyapatite/collagen/poly(L-lactic acid)(nHAC/PLA)co-cultured with bone marrow stromal cells(BMSCs)in treatment of rabbit mandibular defect.and to make a comparison with autogenous bone and simple nHAC/PLA.DESIGN.TIME AND SETTING:A randomized controlled animal experiment was performed at the Animal Laboratory of Jinzhou Central Hospital between March and October 2007.MATERIALS:A total of 40 New Zealand rabbits were randomized to 4 groups.with 10 rabbits per group:nHAC/PLA co-cultured with rabbit BMSCs(BMSCs/nHAC/PLA),autogenous bone,nHAC/PLA,and control.METHODS:A 15 mm×15 mm full-thickness bone defect was created in rabbit mandible body.In the BMSCs/nHAC/PLA group.bone defect was repaired by nHAC/PLA co-cultured with BMSCs for 14 days in vitro;the bone defect in the autogenous bone and nHAC/PLA groups was treated by autogenous iliac bone and nHAC/PLA.respectively;while the control group received no any treatment.MAIN OUTCOME MEASURES:At 1,3,and 6 months after surgery,bone mineral density(BMD)measurement and histological examination were performed to evaluate the repairing effects of bone defect.RESULTS:The BMSCs/nHAC/PLA group exhibited the BMD similar to the autogenous bone group(P＞0.05),but it was significantly higher compared to the nHAC/PLA group and the blank control group(P＜0.01).At 6 months after surgery.newly formed bone tissue grew towards large bulk and bridged defected stumps.and the seaffold materials were hardly seen in the BMSCs/nHAC/PLA and autogenous bone groups;simultaneously.the nHAC/PLA group exhibited increased trabecular bone with many fibrous tissues and incompletely degraded seaffold materials.CONCLUSION:BMSCs/nHAC/PLA seaffold exhibits the effects similar to autogenous bone.but superior to nHAC/PLA seaffold in the treatment of mandibular defects.

Objective To evaluate the potential mutagenicity of a new machinable bioactive glass-ceramic material.Methods Thirty N1H mouse inbred line (female:male =1:1) were divided to three groups at random (n =10),including glass-ceramic groups (oral administration of 5 g/kg glass-ceramic powder and arabic gum),negative control group (arabic gum in equal volume),and positive control group (oral administration of 40 mg/kg cyclophosphamide).The mice orally intook the equivalent liquor and were sacrificed with bone marrow cells abstracted 24 hours later.The micronucleated cells were counted in 1 000 polychromatic erythrocytes (PCE) per mouse,then the rate of the micronucleus in every group was measured.Results The rate of the micronucleus in glass-ceramic group,negative control group and positive control group was 1.31±0.53‰, 1.32±0.62‰ and 29.20±0.74‰ respectively.There was no significant difference in the rate of the micronucleus between the experimental and negative groups (P＞0.05),while a significant difference in the rate of the micronucleus was observed between experimental and positive groups (P＜0.01).Conclusion The new machinable bioactive glass-ceramic materials couldn't increase the micronucleus rate of mouse bone marrow cells.

OBJECTIVE: To determine the effect of different denture cleaning methods on surface roughness in resin denture base. METHODS: We established 20 wafer samples of fuser base resin (14 mm×14 mm×3 mm), and then randomly divided them into 4 groups: group A was the control group, which were placed in water, while group B, C and D were the experimental groups, whose cleaning methods were toothbrush and water, toothbrush and toothpaste, denture cleaning tablets, respectively. Each procedure in group B and C lasted for 3 seconds, but group D lasted 5 min and repeated for 1080 times. We cleaned twice a day to simulate the method of cleaning dentures. Surface roughness was checked after different procedures by laser scanning confocal microscopy. RESULTS: Significant difference on surface roughness was found between group B, C and A (P<0.05), while no significant difference in the surface roughness between group A and D (P>0.05). CONCLUSION Significant surface roughness alterations have been observed in toothbrush and toothpaste group, but no change has been found in denture cleaning tablets group, which does not produce scratches on the surface of resin denture base.
Acrylic Resins ; Denture Bases ; Denture Cleansers ; Dentures ; Random Allocation ; Surface Properties ; Toothbrushing