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    28 January 2018, Volume 34 Issue 1 Previous Issue    Next Issue

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    Endocrown
    CHEN Zhi, CHEN Rui-tian.
    2018, 34(1): 1-5.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.001
    Abstract ( 1780 )   PDF (1366KB) ( 1603 )  
    Endocrown was defined as a restoration fixed to a depulped tooth, which was anchored to the internal portion of the pulp chamber and to the cavity margins, thus obtaining macromechanical retention (provided by the pulpal walls), and microretention (by using adhesive cementation). As the development of restorative materials and adhesive techniques, endocrown received increasing attention due to its minimal tooth preparation and reduced chair-side time. This paper reviewed recent researches about endocrown in the aspect of its definition, indications, tooth preparation, materials, and performance compared to crown and post-and-core crown.
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    Effect of BaTO3/P (VDF-TrFE) Nanocomposite Membrane on Proliferation and Proliferation of Stem Cells
    LI Yi-ping, DAI Xiao-han, TANG Zhan-gui, ZHANG Xue-hui
    2018, 34(1): 6-9.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.002
    Abstract ( 317 )   PDF (2084KB) ( 297 )  
    Objective: To investigate the effect of BaTO3/P(VDF-TrFE) piezoelectric nanocomposite membrane with different barium titanate contents on the adhesion, spreading, and proliferation of rat bone marrow mesenchymal stem cells to provide the basis for optimizing the biological properties of the electroactive materials. Methods: BaTO3/P(VDF-TrFE) piezoelectric nanocomposite films containing different contents of barium titanate nanoparticles (0vol%, 1vol%, 3vol%, 5vol%) were prepared by solution casting method. The surface morphology and microstructures were characterized by scanning electron microscopy and atomic force microscopy. X-ray diffraction was used to detect the chemical composition of the materials. The ferroelectric tester was used to test the piezoelectric properties of the materials. The rat BMSCs of P3-P5 generation were cultured on BaTO3/P (VDF-TrFE) piezoelectric nanocomposites containing different barium titanate after polarization treatment. The adhesion spread and proliferation of BMSCs were detected by scanning electron microscopy and CCK-8, respectively. SPSS13.0 software was used to analyze the statistical analysis by one-way ANOVA. Results: The piezoelectric properties of nanocomposite films showed barium titanate content dependence. Conclusion: BaTO3/P(VDF-TrFE) piezoelectric nanocomposite films containing 5 vol% barium titanate nanoparticles can promote the adhesion, spreading, and proliferation of BMSCs.
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    Effect of Primary Cilia on Expression of Osteogenic-related Genes of Human Periodontal Ligament Cells
    JIANG Si-qi, YIN Feng-ying, ZHANG Fan, WANG Min, XIA Hai-bin
    2018, 34(1): 10-13.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.003
    Abstract ( 389 )   PDF (1268KB) ( 250 )  
    Objective: To study the expression of osteogenic-related genes of human periodontal ligament cells (hPDLCs) by knocking down IFT88 to inhibit the formation of primary cilia. Methods: Control shRNA and shIFT88 were infected into hPDLCs. The expression of IFT88 was detected by qRT-PCR and Western blot. The formation of primary cilia was detected by immunofluorescence and the expressions of osteogenic-related genes COL1A1, OCN, Runx2, and BMP2 were detected by qRT-PCR. Results: The PKLO.1-shIFT88 was stably expressed in hPDLCs and inhibited the expression of IFT88 effectively (P<0.01). The formation of primary cilia was partly suppressed (P<0.01). The expressions of osteogenic-related genes like COL1A1, OCN, Runx2, and BMP2 were decreased significantly (P<0.01). Conclusion: Knockdown IFT88 inhibited the formation of primary cilia and reduced the expressions of osteogenic-related genes of hPDLCs.
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    Expressions of SSUH2 during Mouse Tooth Germ Development
    CHEN Dong, LU Fang-li, LI Xiao-cong, WANG Ying-ying, LI Qiang
    2018, 34(1): 14-17.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.004
    Abstract ( 249 )   PDF (2129KB) ( 292 )  
    Objective: To investigate the role of Ssuh2 associated with dentin dyspepsia type I (DD-I) in the period of tooth germ development in mice. Methods: The time of E13.5d, E14.5d, E16.5d, P2.5d, and P7d were determined by HE staining. The expression of SSUH2 was observed by immunohistochemistry. Results: During the bud stage (E13.5d), SSUH2 was positively expressed in epithelial cells and mesenchymal cells. During the cup period (E14.5d) and the early bell stage (E16.5d), SSUH2 was strongly positively expressed in the basement membrane, internal and external epithelium, enamel knot, and cervical loop. During the cell differentiation and secretory stage (P2.5d) and mineralization stage (P7d), SSUH2 was strongly expressed in ameloblasts, odontoblasts, enamel, and epithelium root sheath. Conclusion: SSUH2 was expressed during all stages of mouse tooth germ, however, the expression of SSUH2 was slightly different in each period. SSUH2 might involve in the development of tooth germs in mice.
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    Effect of DDIT3 Overexpression on Proliferation and Differentiation of HDPCs
    WANG Li-jun, LIU Qiong
    2018, 34(1): 18-21.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.005
    Abstract ( 219 )   PDF (1035KB) ( 208 )  
    Objective: To investigate the effect of DDIT3 overexpression on proliferation and osteogenic/odontoblastic differentiation of HDPCs. Methods: DDIT3 overexpression lentiviral construct was confirmed by sequencing. Generation of lentiviral vectors was accomplished using a three-plasmid transfection procedure. Cells were allocated into three groups: HDPCs-WT group, HDPCs-GFP group, and HDPCs-DDIT3-overexpression group. Expression of DDIT3 was quantified by qRT-PCR and Western blot. Cell proliferation and osteogenic/odontoblastic differentiation were detected by MTT, qRT-PCR, ALP staining, Alizarin red staining, and von Kossa staining. Results: A lentiviral vector system was used to efficiently overexpress DDIT3 in primary HDPCs to levels >90%. It was found that DDIT3 mRNA was overexpressed over 38-fold. MTT assay revealed DDIT3 overexpression reduced HDPC proliferation by 72 and 96 hours compared to control groups. DDIT3 overexpression led to no significant difference in ALP staining area after 7 days culture in odontoblastic medium. However, DDIT3 overexpression enhanced calcium deposition by day 14, as examined by alizarin red and von Kossa staining. qRT-PCR results revealed that DDIT3 overexpression did not affect ALP and RUNX2 mRNA levels, however, it significantly increased OSX, DSPP, DMP1, and OCN mRNA levels by day 14. Western blot analysis revealed that DSPP protein levels were higher in the HDPCs-DDIT3-overexpression group. Conclusion: Lipid metabolism related gene DDIT3 may correlate with HDPCs late osteogenic/odontoblastic differentiation.
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    Repair of Rabbits Critical Mandibular Defects with BMSCs/NHAC Complex
    LI Dong-mei, LIU Xin-hui, LI Qing-xing.
    2018, 34(1): 22-26.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.006
    Abstract ( 260 )   PDF (2439KB) ( 252 )  
    Objective: To investigate the effect of BMSCs/NHAC complex on repair of rabbit's critical mandibular defects. Methods: MTS experiments were used to detect cell proliferation. ALP activity was measured by alkaline phosphatase activity assay. The osteogenic gene was detected by qRT-PCR. The complex was implanted into the mandibular critical defect of rabbit. Goldner trichrome staining test and micro-CT were used to evaluate bone regeneration. Results: OD490 values were significantly higher in the co-culture group than that in the normal group (P<0.05). ALP activity in the co-culture-induced group was significantly higher than that in the normal induction group, as well as the expression levels of OCN, Runx2, and Osterix mRNA (P<0.05). Compared with the black group, the bone volume and bone density of NHAC group and BMSCs/NHAC group were significantly increased (P<0.05). Conclusion: BMSCs/NHAC complexes can promote the bone regeneration in the mandibular critical defect of rabbit.
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    Effects of Lemon Essential Oil on Acid Production and Activity of Lactic Dehydrogenase in Streptococcus Mutans
    SUN Yan-wei, LIU Ya-li, ZHAO Xiao-xue, HOU Fei-fei, ZHANG Xiang-yu
    2018, 34(1): 27-31.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.007
    Abstract ( 330 )   PDF (948KB) ( 333 )  
    Objective: To investigate the effects of LEO on the acid production and activity of lactate dehydrogenase (LDH) in Streptococcus mutans, and to provide a theoretical basis for the application of lemon essential oil (LEO) in oral cavity. Methods: According to the minimal inhibitory concentration (MIC) of LEO, the dilution of 1/8MIC, 1/4MIC, 1/2MIC of LEO and the control group (only contained medium) were prepared by using two-fold dilution method. Streptococcus mutans was added into each group and cultivated for 24h. △pH of medium in each group was determined. The method of oxidation of reduction coellzymeⅠand RT-PCR were respectively adopted to evaluate the activity of LDH and the expression of ldh gene related to acid production. Results: With increasing concentrations of LEO, a dose-dependent decline of △pH (1.423-0.067) and the activity of LDH (33.279-13.367 U/mg) was observed in the LEO group compared to the control group at sub-MIC levels (P<0.01). Compared to the control group, the expression of ldh gene significantly decreased (P<0.05). Conclusion: Sub-MICs of LEO inhibited the activity of LDH and reduced acid production by down-regulating the expression of ldh gene without affecting bacterial growth.
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    Prevalence of Dental Caries and Related Risk Factors in Primary School Students
    YE Zhen, GAO Kai-xian, YIN Xiao-qing
    2018, 34(1): 32-34.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.008
    Abstract ( 351 )   PDF (787KB) ( 417 )  
    Objective: To analysis the prevalence of dental caries in primary school students, and to summary the risk factors. Methods: 2165 students of 3 primary schools were selected as sample, who were carried out the caries examination. A questionnaire survey was conducted to investigate the risk factors of dental caries among pupils and their parents. Results: A total of 2165 questionnaires were issued and 2138 were recovered, with an effective recovery rate of 98.8%. 2032 students had decayed teeth, and the caries rate was 95%. The lower the age, the higher the number of caries in pupils, and the caries rate at different ages was statistically significant (P<0.05). The parents' education level, brushing habits, bedtime eating sweets, often eating sweets, often drinking carbonated drinks, and nearly 12 months to carry out oral examination were risk factors for primary caries. Conclusion: The problem of dental caries in primary school students is serious. It is necessary to increase the awareness of parents, change the habit of brushing teeth and eating, and urge the oral examination to inhibit the occurrence of dental caries.
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    Ascorbic Acid Carbon Dots Kill Tongue Squamous Cell Carcinoma Cell by Promoting Autophagy
    LIU Yu-lan, MENG Lin, TANG Qi, BU Wen-huan, HUANG Guo-shuai, DAI Yi-bin, LIU Qi-lin, SUN Hong-chen
    2018, 34(1): 35-38.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.009
    Abstract ( 338 )   PDF (2067KB) ( 425 )  
    Objective: To study the lethal impact and mechanism of ascorbic acid carbon dots (AACDs) on tongue squamous cell carcinoma cell line Cal27. Methods: The blank control group was untreated Cal27, while the groups treated with AACDs, 3-methyladenine, and both of them were the experimental groups. MTT assay was used to detect the cell proliferation. Acridine orange staining was used to evaluate the cell autophagy. Flow cytometry was performed to examine cell apoptosis. Results: AACDs suppressed the proliferation of Cal27 on a dose-dependent manner. It also induced the autophagy of Cal27, especially in the 100 μg/ml AACDs group. When 3-methyladenine was added to induce the autophagy level, cell proliferation level was improved with the decrease of apoptotic rate. Conclusion: AACDs kill tongue squamous cell carcinoma cells through promoting autophagy.
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    Effect of Plumbaginon on Invasion and Migration of Tongue Squamous Cell Carcinoma Cells and Its Mechanism
    ZHOU Xiong-ming, NA Si-jia, PAN Shu-ting, QIU Jia-xuan
    2018, 34(1): 39-43.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.010
    Abstract ( 271 )   PDF (3582KB) ( 358 )  
    Objective: To investigate the relationship between Glucose transporter isoform 1 (GLUT1) and metastasis of tongue squamous cell carcinoma (TSCC) and the effect and mechanism of plumbagin (PLB) on the invasion and migration of TSCC cells. Methods: The relationship between metastasis of TSCC and GLUT1 or Matrix metalloprotein 2 (MMP2) was detected by immunohistochemical assay. The proliferation inhibition effect and the half inhibitory concentration (IC50) of plumbagin on TSCC cells were detected by MTT assay. The invasion ability and migration ability were detected by Transwell assay and wound healing test, respectively. And the expressions of p53, GLUT1, and MMP2 were evaluated by Western blot. Results: The high expression of GLUT1 and MMP2 was closely related to the metastasis of TSCC (P<0.05). MTT assay showed that the IC50 of PLB to TSCC cells for 24h was 6.78μmol/L. Transwell assay and wound healing test showed that PLB and NSC207895 and WZB117 significantly reduced the number of transmembrane cells and cell mobility. Western blot showed that the expression of p53 increased, while the expression of GLUT1 and MMP2 decreased after treatment of PLB (P<0.05). The expression of GLUT1 and MMP2 decreased (P<0.05) after treatment of NSC207895. And the expression of MMP2 decreased (P<0.05) after treatment of WZB117. However, the expression of p53 was not changed (P>0.05). Conclusion: The high expression of GLUT1 is closely related to the metastasis of TSCC. Plumbagin can inhibit the invasion and migration of TSCC through p53/GLUT1/MMP2 pathway.
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    Expression and Significance of Vitronectin in Blood Serum of Oral Squamous Cell Carcinoma
    TIAN Bing, HU Teng-long, JING Guang-ping, YU Yang, ZHONG Ke-tao, WANG Hai-tao, YU Qing
    2018, 34(1): 44-46.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.011
    Abstract ( 234 )   PDF (1051KB) ( 293 )  
    Objective: To observe the expression of blood serum vitronectin (VTN) in oral squamous cell carcinoma (OSCC), and to explore its clinical significance and the degree of differentiation, as well as the correlation between cervical lymph node metastasis. Methods: Western blot method was used to detect VTN expression in 26 OSCC patients without lymph node metastasis, including 18 OSCC patients with lymph node metastasis, 8 oral tissue atypical hyperplasia patients, 20 healthy people from Department of Oral and Maxillofacial Surgery, affiliated Stomatological Hospital of Harbin Medical Universit from 2016,08,01-2017,05,30. Results: VTN was highly expressed in the blood serum of healthy people (36849.10±1127.37) than that of OSCC patients without lymph node metastasis (22518.12±1301.25). VTN was also highly expressed in the blood serum of OSCC patients without lymph node than that of OSCC patients with lymph node metastasis (9459.28±629.58, P<0.001). VTN was 36725.50±1484.41 in the blood serum of patients with atypical hyperplasia of oral mucosa. The expression of VTN in OSCC patients with different differentiated degree and without lymph node metastasis was analyzed. The results showed that VTN was highly expressed in the blood serum of high differentiated OSCC patients (59009.13±145.75) than that of moderately differentiated OSCC patients (39468.82±1135.61). And its expression was also higher than that of poorly differentiated OSCC patients (22437.00±1286.38, P<0.001). Conclusion: VTN may be associated with the malignant transformation and mestastasis of OSCC, and expression of serum VTN may help OSCC diagnosis and disease progression assessment.
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    Efficacy of Injection Methods in the Treatment of Pterygoid Muscle Spasms
    JIA Meng-ying, LIU Hui, HU Lu-lu, XU Ying-jie, GU Wen-yan, WU Ze-yu, GONG Zhong-cheng
    2018, 34(1): 47-51.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.012
    Abstract ( 309 )   PDF (1233KB) ( 280 )  
    Objective: To evaluate the efficacy of injection methods (1∶1∶1 mixed of lidocaine, methotrexate, and dibandolone) in the treatment of pterygoid muscle spasms. Methods: Twenty-eight cases were diagnosed as pterygoid muscle spasms and treated with injection methods for three times. Assessments were carried out including the clinical features, VAS score, mandibular movement, and Fricton index. Results: A significant difference (P<0.05) after three injections was found in the VAS score, mouth opening degree, laterality and protrusion movements, and Friction index compared with pre-treatment. Conclusion: It is suggested that the injection method might be an effective treatment for the pterygoid muscle spasms.
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    An Evaluation Study of Facial Nerve Function in Different Parotid Surgical Methods
    TAO Feng, HE Deng-qi, DU Hong-liang, YU Tao, CHE Yin-fu, XUE Gang
    2018, 34(1): 52-55.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.013
    Abstract ( 235 )   PDF (1639KB) ( 273 )  
    Objective: To evaluate facial nerve injury of the anterograde exposing method and the retrograde exposing method of facial nerve in benign lesions of the parotid gland. The facial nerve function (ENoG) and the House-Brackmann (H-B) scale were used to evaluate the extent of the facial nerve injury. To investigate the pros and cons of two surgical methods and evaluate the applicative prospect of ENoG examination in prognosing the outcome of facial nerve injury. Methods: Included in this study were 36 patients with unilateral benign lesions of the parotid gland who were admitted to the Department of Stomatology of the First Hospital of Lanzhou University from April to May 2017. They all received parotidectomy by either anterograde or retrograde method of exposing facial nerve by the same surgeon. The extent of facial nerve injury was evaluated by ENoG and H-B scale, and the correlation between two evaluation methods was studied. Results: The incidence of facial paralysis and facial nerve recovery time were lower in the anterograde group than in the retrograde group. There was a correlation between subjective H-B scale and objective ENoG parameters. Conclusion: Parotidectomy by the anterograde method of exposing facial nerve is superior to the retrograde method with regard to the potentiality of facial nerve injury. It is suggested that ENGG should be introduced into facial nerve function evaluation system as an objective index for evaluating facial nerve injury.
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    Application of 3D Printing Technology in Immediate Prosthetic Restoration of Anterior Maxillary Defect
    DU Bao-xia, WANG Xiao-rong, YIN Guo-xiang, YANG Gang, ZHANG Wei
    2018, 34(1): 56-59.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.014
    Abstract ( 281 )   PDF (1258KB) ( 376 )  
    Objective: To explore the applicative value of 3D printing technique in immediate prosthetic restoration of anterior maxillary defect. Methods: Three patients with anterior maxillary defect were selected. For the purpose of immediate prosthetic restoration, defect models were reconstructed, and individual prostheses were designed, customized and prefabricated by 3D printing technique. Results: All three patients after immediate prosthetic restoration were satisfied with the restoration of facial features and clear speeches. Conclusion: The results suggest that the immediate prosthetic restoration of anterior maxillary defect by 3D printing technique has clinical applicative values.
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    Middle Temporal Vein Guided Flapping in Coronal Incision: a Clinical Study
    SONG Yong, WANG Jun-lin, LIU Yan-jie, CHEN Yu-cong, HE Hu-jie, WANG Bo-hao
    2018, 34(1): 60-64.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.015
    Abstract ( 320 )   PDF (2887KB) ( 303 )  
    Objective: To investigate the role of middle temporal vein in coronal incision. Methods: Thirty-six patients with zygomatic fractures in our hospital were included. All fracture segments were exposed by coronal incision along the plane of middle temporal vein or deep temporal fascia. Factors taken into the study included flapping time, bleeding volume, variation of middle temporal vein, and clinical outcomes. Results: The middle temporal vein ran constantly through superficial part of temporal fat pad between the two layers of deep temporal fascia. All 18 middle temporal vein cases were recorded without middle temporal vein missing, with successful flapping, intact temporal fat pad, good exposure, and satisfactory reduction of fractures. Transient facial paralysis was reduced significantly in the middle temporal vein group, while permanent facial nerve injury and temporal hollowing showed no significant difference. Conclusion: Temporal flapping guided by middle temporal vein is a simple and clear way that can reduce facial nerve injury and temporal hollowing in coronal incision.
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    Biomechanical Analysis of Endocrown of Mandibular First Molar with Different Proximal Heights
    WU Fan, CAO Liang, JIANG Xiao-nan, ZHAO A-li, ZHANG Guo-qing, WANG Li-min, WANG Wei-guo
    2018, 34(1): 65-68.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.016
    Abstract ( 268 )   PDF (2333KB) ( 253 )  
    Objective: To compare the stress and its distribution of the residual tooth tissue and the restoration of the mandibular first molar with proximal defect with different heights so as to provide reference for the clinical repair plan. Methods: The mandibular first molar model with proximal defects at different heights was established by finite element method and repaired with endocrown. Then, the vertical and oblique loads were applied, and the size and distribution of EQV stress of residual tooth tissue and restoration were recorded. Results: The EQV stress distribution of the residual tooth tissue and the endocrown was similar in different groups. The maximum EQV stress of the residual tooth tissue and the endocrown increased with the decrease of the residual height. Conclusion: The decrease of the proximal height increases the stress of the endocrown and the residual tooth tissue, and increases the possibility of fracture of the tooth and endocrown.
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    Three-dimensional Geometric Morphometric Analysis of First Permanent Molar Crowns
    LU Peng-fei, YU Qing, ZHONG Yi-cheng, YU Nian, CHENG Gong-pei
    2018, 34(1): 69-72.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.017
    Abstract ( 296 )   PDF (2153KB) ( 486 )  
    Objective: To research the shape of the first permanent crowns, and to quantify and compare the three-dimensional morphological differences between crowns. Methods: One hundred pairs of Chinese juvenile dental plaster models were 3D optical scanned, including fifty pairs of males and fifty pairs of females. Principal component analysis was performed to assess the shape parameters. With the help of thin plate spline (TPS), the anatomical significance of each principal component was explored. Results: The first five principal components of the first upper and lower permanent molars comprised almost 70-80% of the molar shape variations, and the first two most important principal components were related to the mesiodistal-buccolingual ratios and the relative cusp positions. The tooth size was significantly correlated (r2=0.703), and the male molars were larger than the female molars (2.68% and 1.66% for the upper and lower molars, respectively), but no shape dimorphism was observed. Conclusion: The shape variations of upper and lower permanent molars were related to mesiodistal-buccolingual ratios, heights between teeth tips and fossea, and relative cusp positions. Distal cusps of lower permanent molar showed the highest variability. Sexual dimorphism was limited to size difference and the shape variation was weak.
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    Influence of Framework Design on Fracture Strength of Zirconia Crown
    LI Ya-qin, LV Wen-fang, CAO Yang, CAO Gui-zhen, PENG Fei, YANG Fang, LU Su-lai, YU Jiang-bo, Chen Shu-lan, GUO Da-wei
    2018, 34(1): 73-76.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.018
    Abstract ( 257 )   PDF (1388KB) ( 219 )  
    Objective: To explore the optimal design of the framework so that to improve the fracture strength of the zirconia crown. Methods: Four different framework designs based on the thickness of zirconia cervical collar were used: 0.00mm zirconia collar(Group A), 1.00mm (Group B), 2.00mm (Group C), and height of contour(Group D).There were 7 samples in each group. The universal test machine was used to test the fracture load. The damage shape was observed by the body type microscope and scanning electron micrographs. Results: Mean of fracture loads were 1.56KN for Group A, 1.83KN for Group B, 1.95KN for Group C, and 2.27KN for Group D. The fracture load of four groups showed a significant difference. Group A was significantly different from Group D. Damage shapes were crack and chipping. There was no significant difference in the composition ratio between four sets of damage shapes. Conclusion: The framework design can affect the fracture strength of the zirconia crown, and the more thick of zirconia collar, the higher fracture strength of zirconia crown.
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    Establishment of Mathematical Model of Skeletal Class Ⅱ Malocclusion Based on 2D Projection Point Set
    MA Yi-meng, GAO Hui, XIAO Dan-na, FANG Shu
    2018, 34(1): 77-81.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.019
    Abstract ( 239 )   PDF (2143KB) ( 276 )  
    Objective: To describe the dental form and basal bone arch form of skeletal Class Ⅱ malocclusion patients by transforming 3D image data to 2D plane and establishing a mathematical model. Methods: CBCT data of 30 patients with skeletal Class Ⅱ malocclusion were selected. Occlusion plane with mathematical algorithm by dental form point (Fa) and basal bone arch form point (Ba) was determined. 3D image data was transformed to 2D plane with Software Matlab 7.0. Results: The mathematical model describing the dental arch and basal bone arch form of skeletal ClassⅡ malocclusion was established: 1) dental arch: maxillary Y=41.01[1- (2X/61.08)2]0.73; mandibular Y=37.35[1- (2X/59.55)2]0.717; 2) basal bone arch: maxillary Y=29.15[1- (2X/65.63)2]0.721; mandibular Y=30.91[1- (2X/79.19)2]1.24. Conclusion: A function equation which has high fitting degree with the dental form and basal bone arch form of the skeletal Class Ⅱ malocclusion patients was established. The function equation and the measurement data from it can guide further research
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    Study of Relative Aesthetic Parameter on Asymmetric of Central Incisors Gingival Margin
    CHEN Jun-chi, GUO Ling
    2018, 34(1): 82-86.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.020
    Abstract ( 304 )   PDF (3519KB) ( 320 )  
    Objective: To study the sensitivity and acceptability of different groups for the asymmetry of central incisors gingival margin, to explore the views of different people on the aesthetics of soft tissue, and to guide the clinicians for better repair of anterior teeth. Methods: This experiment is randomized and controlled trial. Participants (913) were divided into A, B, C three groups. Gingival margin pictures with different degrees of asymmetry were disordered and subjected for VAS score and acceptance by three groups, which was used to learn the sensitivity and acceptance. Results: The minimal detection rates of dental professionals were ±0.75mm (P<0.05), and those of laypersons were +1.00mm and -1.50mm (P<0.05). Dental professionals’ 50% acceptance values were ±1.00mm and those of laypersons were +1.50mm and -1.25mm. Conclusion: Professionals are easier to detect gingival changes than laypersons, and they have small range of acceptance.
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    Expression of IL-6 and Shh in Gingival Crevicular Fluid of Patients with Peri-implantitis
    CHENG Zhi-fen, CUI Lian-bao, XUAN Yan-hua
    2018, 34(1): 87-89.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.021
    Abstract ( 273 )   PDF (787KB) ( 255 )  
    Objective: To study the expression of IL-6 and Shh in patients with peri-implantitis. Methods: Twenty-five patients were included and divided into health implant group (10 cases) and peri-implantitis group (15 cases). The expressions of IL-6 and Shh in health implant group and peri-implantitis group were detected by ELISA assay. Results: The expressions of IL-6 and Shh in the peri-implantitis group were significantly higher than those in the health implant group (P<0.001). There was no positive correlation between IL-6 and Shh (P>0.05). Conclusion: IL-6 and Shh were increased in gingival crevicular fluid of patients with peri-implantitis, and Shh might be a marker to determine the progress of peri-implantitis.
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    Ectopic Salivary Gland in the Middle Region of Neck Was Misdiagnosed as Thyroglossal Cyst: A Case Report
    YANG Nan, ZHANG Rui, WANG Ru
    2018, 34(1): 90-91.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.022
    Abstract ( 267 )   PDF (1259KB) ( 282 )  
    The presence of salivary gland tissue in abnormal regions is referred to estopia. Ectopic salivary gland presents in the middle region of neck is extremely rare. We report a case of a female aged 57 years with ectopic salivary gland that was misdiagnosed as thyroglossal cyst.
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    Application of Platelet Rich-Fibrin in Posterior Immediate Implantations: A Case Report
    ZHOU Jing, SUN Xiao-lin, QI Man-lin, DING Xin-xin, LI Xue, ZHOU Yan-min
    2018, 34(1): 92-93.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.023
    Abstract ( 293 )   PDF (1411KB) ( 349 )  
    Objective: To investigate the clinical effectiveness of platelet rich-fibrin (PRF) on immediate implantation in the fresh extraction sites of posterior teeth. Methods: After posterior tooth was extracted, one implant was placed into the fresh extraction site. The PRF clot as grafting materials was packed into the space between the implant and the fresh extraction site to regenerate the bone and periodontal tissue. Results: The radiograph demonstrated that the space around the implant was filled with a dense bone-like tissue. The width of keratinized tissue was greater than 2mm. Conclusion: PRF could serve as a viable material for tissue regeneration around immediately placed implant in the posterior region.
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    Research Status and Perspectives of Biomechanical Signals for Differentiation of Bone Marrow Mesenchymal Stem Cells
    SUN Ling-lu, SU Xue-lian, HE Xiao-lan, BAO Guang-jie, KANG Hong
    2018, 34(1): 94-96.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.024
    Abstract ( 363 )   PDF (807KB) ( 424 )  
    Because of multidirectional differentiating potentials, bone marrow mesenchymal stem cells (BMSCs) are considered as an important source of seed cells in tissue engineering. However, how to induce BMSCs into the target cells is challenging. Biomechanical signals can affect the differentiation of BMSCs by multiple ways such as loading types, intensity, frequency, and duration time of stress. The degree and directions of differentiation of MSCs are dependent on the interaction of BMSCs-extracellular matrix (ECM), cytoskeleton reorganization and reconstruction, integrin signal pathway and ion channels change, and focal adhesion formation in the process of cell transduction.
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    Progress of Application and Research on Antioxidants and Periodontitis
    WEN Jing-yu, HE Hong-bing, REN Xiao-bin, JIANG Jie
    2018, 34(1): 97-99.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.025
    Abstract ( 381 )   PDF (799KB) ( 517 )  
    Periodontitis is one of the most popular diseases in oral cavity. Many researches have indicated that excess reactive oxygen species that resulted in oxidative stress might have a close relationship with periodontitis. Antioxidants can decrease the level of oxidative stress by effectively suppressing reactive oxygen species generation, thereby suggesting their potential usefulness for the treatment of periodontitis. In order to provide a reference for further investigation, the production of reactive oxygen species and oxidative stress, the pathological mechanism of periodontitis, and the application of antioxidants in periodontitis were reviewed in this article.
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    Research Progress of Music Therapy in Treatment of Periodontal Diseases
    LIU Yue-fang, ZHU Guang-xun
    2018, 34(1): 100-102.  DOI: 10.13701/j.cnki.kqyxyj.2018.01.026
    Abstract ( 347 )   PDF (798KB) ( 354 )  
    As a kind of non-drug intervention method, which could affect patient's physiological and psychological condition, music therapy has been used clinically in the fields of oral diseases. This paper reviews the advancement of music therapy in the treatment of periodontal diseases.
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