With the rapid development of the field of interventional therapy of cardiac valve, the innovative researches of interventional therapy of cardiac valve products have become the focus of global research. At present, there is a serious shortage of interventional valvular medical devices on the market in China, and large-scale interventional valve products are undergoing early human trials or confirmatory clinical trials. The effective quality control of clinical trials is of great significance to ensure that clinical trial data can be used to support the marketing of device products. By analyzing the problems in clinical trials quality control of interventional valvular medical devices in our hospital, and combining the characteristics of device products and diseases, we explore the key points of quality control and provide reference for the implementation and completion of high-quality clinical trials.

Objective: Through a pain study of buccal gingival mucosa sensitivity of the mandible, the corresponding sensitive area of pain was determined, which provided the basis for reducing the pain and discomfort of oral diagnosis and treatment. Methods: 400 patients with mandibular tooth extraction in the outpatient department of stomatology were selected. During tooth extraction, articaine epinephrine injection was used for infiltration anesthesia. The injection needle size was 0.3 mm × 21 mm, and the injection site was about 5 mm away from the buccal gingival margin. The pain degree of the patients was recorded. The data were statistically analyzed using the modified International pain classification method. Results : Among the 400 patients who underwent mandible extraction, 75% (300 patients) graded their pain from painless to moderate, and 25% (100 patients) reported moderate to severe and severe pain. Of those in the moderate to severe and severe groups, 50% and 42% reported pain in the central and lateral incisors, respectively, and 38% were in the canine group. When comparing the moderate to severe and the severe groups, 16% and 10% were in the bicuspid group, 16% and 12% and 16% were in the molar group, respectively . There were significant differences in the pain sensitivity of different teeth positions (χ2=54.203, P < 0.001). The proportion of moderate to severe and severe pain in the anterior teeth group was higher than it was in the posterior teeth group (χ2=55.555, P < 0.001). There were significant differences in the pain sensitivity of different ages (χ2=96.501, P=0.000), and there was a positive correlation between pain and age (r=0.465, P < 0.001). The proportion of women with at least a moderate degree of pain was higher than that of men (χ2=12.298, P=0.031). Conclusion The sensitivity of the buccal gingival mucosa to pain is different in different positions of the mandible. The sensitivity of the anterior gingiva is higher than that of the posterior gingiva. Age is positively correlated with the degree of pain. Further, compared with men, women are more sensitive to pain.

Objective:To investigate the relationship between pulp chamber height and dentine thickness of mandibular first molar on long axis with age in a Chinese Han population by cone-beam computed tomography(CBCT).Methods:CBCT images of 420 Chinese Han subjects(210 males and 210 females) were divided into 6 age groups as follows:15-24,25-34,35-44,45-54,55-64 and 65-74 years(n=70,35 males and 35 females).The height of pulp chamber and dentine thickness of the chamber root and floor of mandibular first permanent molar on long axis was measured by Galileo software of CBCT in vertical direction and then statistical analysis was carried out.Results:On long axis,the height of pulp chamber was (0.85±0.54) mm in males and (0.79±0.51) mm in females(P>0.05);dentine thickness of the pulp chamber roof was (3.60±0.49) mm in males and (3.50±0.49) mm in females(P>0.05);and dentine thickness of the pulp chamber floor was (2.57±0.52) mm in males and (2.49±0.5) mm in females(P>0.05).With aging,the height of pulp chamber was decreased(P<0.05) and dentine thickness of mandibular first permanent molar on long axis was increased(P<0.05).Conclusion:In Chinese Han population,the of pulp chamber height of mandibular first permanent molar on long axis is related to age,The dentine thickness increased with ages,the increase of dentine thickness of pulp chamber floor is more significant than that of the roof.

Objective:To investigate the correlation between root and root canal diameter of maxillary central incisors and age by cone-beam computed tomography(CBCT).Methods:CBCT images of 420 cases of Chinese Han population were divided into 7 age groups as follows:1 5 -24,25 -34,35 -44,45 -54,55 -64,65 -74 and 75 -84(n =60).Root diameter and root canal diameter of maxillary central incisors at the 3 /4 level from the cemenal-enamel junction(CEJ)to root apical were measured.Linear-regression a-nalysis was used to analyze the correlation between root and root canal diameter of the teeth and age,T-test was used to examine the gender difference.Results:Mean root diameter(mm)of the teeth in males and females were 5.81 ±0.445 and 5.53 ±0.489(P <0.05),mean root canal diameter(mm)1 .20 ±0.396 and 0.96 ±0.236(P <0.05),mean of the ratio of root canal diameter and root diameter of the teeth 0.21 ±0.072 and 0.1 7 ±0.043(P <0.05)respectively.There were negative correlations between the ratio of root canal diameter and root diameter of the teeth with age (R2 =0.576,P <0.05).Conclusion:The ratio of root canal diameter and root diameter of maxillary central incisors is negitively correlated with age in Chinese Han population.The decrease of root canal diame-ter in males is more significant than that in females.

The differentiation of periodontal ligament (PDL) progenitor cells is important for maintaining the homeostasis of PDL tissue and alveolar bone. Vitamin C (VC), a water-soluble nutrient that cannot be biosynthesized by humans, is vital for mesenchymal stem cells differentiation and plays an important role in bone remodeling. Therefore, the objective of this study was to determine the function and mechanism of VC in PDL progenitor cells osteogenic differentiation at the molecular level. We demonstrated that VC could induce the osteogenic differentiation and maturation of PDL progenitor cell without other osteogenic agents. During the process, VC preferentially activated ERK1/2 but did not affect JNK or p38. Co-treatment with ERK inhibitor effectively decreased the Vitamin C-induced expression of Runx2. ERK inhibitor also abrogated Vitamin C-induced the minimized nodules formation. PELP1, a nuclear receptor co-regulator, was up-regulated under VC treatment. PELP1 knockdown inhibited ERK phosphorylation. The overexpression of PELP1 had a positive relationship with Runx2 expression. Taken together, we could make a conclude that VC induces the osteogenic differentiation of PDL progenitor cells via PELP1-ERK axis. Our finding implies that VC may have a potential in the regeneration medicine and application to periodontitis treatment.
Ascorbic Acid ; pharmacology ; Butadienes ; pharmacology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Co-Repressor Proteins ; antagonists & inhibitors ; genetics ; metabolism ; Core Binding Factor Alpha 1 Subunit ; genetics ; metabolism ; Humans ; MAP Kinase Signaling System ; drug effects ; Mitogen-Activated Protein Kinase 1 ; antagonists & inhibitors ; metabolism ; Mitogen-Activated Protein Kinase 3 ; antagonists & inhibitors ; metabolism ; Nitriles ; pharmacology ; Periodontal Ligament ; cytology ; Phosphorylation ; drug effects ; RNA Interference ; RNA, Small Interfering ; metabolism ; Stem Cells ; cytology ; Transcription Factors ; antagonists & inhibitors ; genetics ; metabolism ; Up-Regulation ; drug effects

OBJECTIVETo observe the temporal and spatial expression of Smad7 during human tooth germ development and evaluate the effect of Smad7 on tooth germ development.

METHODSThe expression of Smad7 and its changes at different stages of human tooth germ were detected by using immunohistochemical staining.

RESULTSSmad7 was expressed at all stages of tooth germ, but the distribution patterns at various stages were different. It indicated that temporal and spatial expressing mode of Smad7 during human tooth germ development was specific, which was similar to that of TGF-beta its signal transducer Smad2/3.

CONCLUSIONSmad7 might play an important role in TGF-beta intracellular signaling for modulating the differentiation of ameloblasts and odontoblasts.

Ameloblasts ; cytology ; Cell Differentiation ; DNA-Binding Proteins ; genetics ; metabolism ; physiology ; Fetus ; Humans ; Immunohistochemistry ; Odontoblasts ; cytology ; Odontogenesis ; Signal Transduction ; Smad7 Protein ; Tooth ; growth & development ; Tooth Germ ; embryology ; Trans-Activators ; genetics ; metabolism ; physiology ; Transforming Growth Factor beta ; genetics ; metabolism ; physiology

砄bjective: To study the mineralization and related differential phenotype of human dental papilla cells in vitro . Methods: Human dental papilla cells were primarily cultured with explant technique, the cells of third passage were incubated for a long term in the presence of 10 mmol/L ? glycerophosphate(? GP)and 50 ?g/ml of ascorbic acid (L AA) in DMEM containing 5% FBS. Alkaline phosphatase (ALP) and osteocalcin(OC) were measured at different culture time. Cell growth was observed under inverted microscope and mineralization was tested with Von Kossa stainning. Results: Cultured papilla cells were growing in multilayer. Cells exposed to ? GP and L AA exhibited higher ALP activity in 14 days and increased OC in 21 days with certain amount of secreted matrix. After 35 days of culture, mineralized tubercles were formed. ALP activity and synthesized OC began to decrease after 42 days of culture. Conclusion: Human dental papilla cells may show odontoblast phenotype in vitro .

砄bjective: To determine the effects of interleukin 1 receptor antagonist( IL lra) on the production of IL 6 induced by IL 1? in human gingival fibroblasts(HGFs). Methods:HGFs at passage 5 were exposed to various concentrations of IL 1? with or without IL 1r? . IL 6 in the culture medium was measured with a sandwish ELISA assay. Results:IL 6(?g/L) produced by HGFs exposed to IL 1? at the concentrations (?g/L) of 0.1, 1.0, 10 and 100 were 207?40.29, 235?80.78, 370?40.62, 570?68.17 and 737.5?83.47 respectively. While that by HGFs exposed to IL 1? at 10 ?g/L with IL 1r?(?g/L) at 1, 10, 100 and 1 000 were 387.5?49.69, 312.5?26.81, 242.5?25.86 and 217.5?21.65 respectively. Conclusion: IL lra can inhibite the IL 1? induced IL 6 production in HGFs.

Objective:To observe the clinical effect of apical barrier and perforation repair with mineral trioxide aggregate.Methods:Selected 23 samples from out-patients of the department of conservative dentistry of oral disease treatment center of 306 Hospital of PLA.Among them,7 samples were with unshaped root apical,6 samples were with lateral perforation from root canal internal absorption or root fracture,10 samples were iatrogenic lateral perforation.The course of the disease was 0.5-24 months.The images of dental films showed that there was shadow around the root or apical area in all the samples.All the samples received regular root canal treatment.Under root canal microscope,the open sites were sealed with MTA.After the barrier formed,filled the root canal with warm gutta-percha vertical compaction technique.Patients were ordered to re-check on 6 months and 12 months respectively.Results:1 sample dropped out.On 6 months visit,1 sample showed enlarged shadow at the apical area,20 samples showed shrinked shadow,1 sample showed no significant change.On 12 months visit,the shadow vanished in 9 samples;the shadow decreased in 5 samples,and there were 2 samples showed no significant changes.Conclusion:The treatment with MTA on apical barrier and perforation shows acceptable effect in short term observation.The use of microscope helps to enhance the accuracy and leak tightness of MTA filling.

Objective To investigate the correlation of the prevalence of periodontitis with age and course of disease in patients with type 2 diabetes.Methods A total of 884 patients with diabetes (both sexes,aged 35-79 yr) were involved in present study.Diagnosis of periodontitis was made according to the 1999 WHO standard,and of type 2 diabetes to the 1997 WHO standard.Age,gender,course of diabetes and periodontal state of those patients were recorded.The patients were grouped according to their age (10 yr interval) and course of disease (5 years interval).Based on the grouping,the collected data were input into ACCESS data bank and statistically analyzed with SAS software,and the prevalence of periodontitis were then compared.Results The prevalence of periodontitis in patients with type 2 diabetes increased with the increasing of age and with the prolonging of disease course (P