Objective To investigate the effects of neurotrophin receptor-mediated melanoma antigen-encoding gene homology (NRAGE) on proliferation of human dental pulp cells (hDPCs) and MDPC-23. Methods Cells were infected by recombinant lentivirus to stably knock down the expression of NRAGE, then in vitro tissue explant method was used to conduct the primary culture of the hDPCs and MDPC-23, and the biological effects of NRAGE on the hDPCs and MDPC-23 were detected. Cell Counting Kit-8 was used to analyze effects of NRAGE on hDPCs and MDPC-23 proliferation, then the cell cycle distributions and apoptosis of hDPCs and MDPC-23 were performed by flow cytometric analysis. Simultaneously, the cell cycle and apoptosis were also detected after cells treated with IKK inhibitor.Then, mRNA and protein levels of NRAGE and nuclear factor-κB (NF-κB) protein expression were detected. Immunofluorescence assay was used to detect expression and location of NRAGE and NF-κB. Results The mRNA and protein levels of NRAGE decreased significantly after infected by recombinant lentivirus. Knockdown of NRAGE inhibited the proliferation and apoptosis of hDPCs and MDPC-23. Knockdown of NRAGE showed significant G0G1 retention in hDPCs, while no significant difference in MDPC- 23. Meanwhile, knockdown of NRAGE activated the NF-κB signaling pathway. After treated with IKK inhibitor, the effect of NRAGE knockdown on apoptosis was reversed in both hDPCs and MDPC-23. Conclusion Knockdown of NRAGE can inhibit proliferation of hDPCs and MDPC-23. NRAGE is a potent regulator for cell cycle and apoptosis of hDPCs. Knockdown of NRAGE can inhibit apoptosis of hDPCs and MDPC-23 through the NF-κB signaling pathway.

Objective ① To evaluate whether manufacturing edentulous jaw individual tray by 3D printing can effectively reduce the clinical chair side time compared with traditional method. ② To compare the fixation strength and changes between alginate impression and the impression surface of trays ［3D printing tray(Polylactic acid/PLA), traditional tray(acrylic resin and light-cured resin)］ after dealt with different ways. Methods ① Select ten models of edentulate patients, then screen maxillary(A) and mandible(B)(n=10). Record the chair side time of fabricating individual trays in 3D and traditional ways. ② Handle the trays by wontfix, the tray binder and punching, measure the fixation strength between the impression surface of 3D printing and traditional trays in the above three conditions and the alginate impression. Results ① The chair side time of 3D printing trays were 34.37 min(A) and 28.19 min(B), while traditional trays were 64.95 min(A) and 63.94 min(B). 3D printing tray cost less time than traditional tray（P<0.05）. ② The trays dealt with tray binder obtained best fixation strength in 3D printing group, which was 2.31 N/cm(ANOVA Factorial design P<0.01). Conclusion ① Compared with traditional tray, 3D printing tray can reduce the chair time effectively. ② 3D printing tray has nice fixation strength, and we can improve the fixation strength by punching or surface tray adhesive,the latter having more obvious effect.

Objective To study the effect of sand blasting and coating binder on the bonding strength of different tray materials and silicone rubber. Methods Stainless steel, auto polymerizing acrylic resin and light cured resin were selected as tray materials. 40 standard test pieces were made of each kind of tray materials. They were randomly divided into four groups with the same material specimens, control group: the specimens were not treated; binder group: the specimens were coated with tray adhesive; sandblasting group: the specimens were sandblasted; spray sand and binder group: specimens were sandblasted and then coated with tray adhesive, and contacted and bonded with silicone rubber material in testing device, then tensile test was conducted, and the results of the calculated binding strength were recorded. Results When sand blasting and binder were used, the binding strength of the three materials was the highest. When sand blasting was used alone, the binding strength of the resin material obviously increased, while the strength of the stainless steel decreased obviously. When the binder was used alone, the binding strength of the three materials significantly improved. Conclusion The best combination of sand and binder significantly improves the bonding strength of the pallet. The use of adhesive or sand blasting in the resin material tray has a certain effect on increasing the bonding strength of the tray. Metal tray using binder can also increase the strength of the tray.

Objective To study the stress distribution rule on the cervical margin of porcelain -fused -to -metal crown(PFM) under two work conditions when two kinds of materials and two designed margins are adopted. Methods The 3-D finite element method was used to perform the computer analog of the maxillary central incisor, and the stress distribution was analyzed on the cervical margin of PFM crown under two work conditions when two kinds of materials and two different designs were adopted. Results The stress on the cervical margin of PFM crown when the ceramic cervical margin was used was very close to that when the metal cervical margin was used, the stress was much lower than the permissible stress strength of ceramic. 120 degree bevel proved more beneficial for protecting the tooth health. Conclusion Under the normal occlusal force, the cervical margin ceramic of porcelain-fused-to-metal crown is not liable to fracture and can be a choice in clinical practice.

Objective To observe and analyze defects in Mtwo instruments after clinical use. Methods A total of 419 Mtwo instruments after clinical use were collected at Nanjing Stomatology Hospital from March 2013 to January 2014. The instruments were examined under a stereomicroscope at 30× magnification. The instruments were divided into three groups:① without defects, intact; ② with defects; ③ fractured or separated. A scanning electron microscope was used to examine some typical changes of the fractured instruments to analyze the separation types. Results 63.5% of the Mtwo instruments showed defects. The incidence of instrument separation was 21.2%. The incidences of instrument separation of four types of Mtwo instruments were respectively #10.04：31.6%，#15.05：13.8%，#20.06：21.0%，#25.06：17.7%. #10.04 was the most frequently fractured instrument (31.6%). Deformations were mostly observed in #15.05 instruments. Cyclic fatigue was the main mechanism for instrument separation of Mtwo. Torsional fracture was observed mostly in #10.04 instruments. According to the SEM, fatigue striations were observed in the instruments fractured because of cyclic fatigue. Dimpled rupture and microvoids could be found in the instruments as a result of torsional stress. Conclusion Cyclic fatigue seems to be an important mechanism for instrument separation of Mtwo rotary instruments. Its proportion in instrument separation is different from that of torsional stress. The rotary file size is correlated with the incidence and mechanism of instrument separation.

Objective To explore the pain involved clinical factors during seating dental implant restoration abutments and establish a multivariable linear regression model. Methods Patients of Dentium implant restoration were collected at the Department of Implantology of Affiliated Hospital of Stomatology of Nanjing Medical University from October 2015 to March 2016. Visual analog scale (VAS) was used to score pain intensity during seating dental implant restoration abutments. The clinical factors related to the pain intensity were measured and recorded, including the implant location of maxilla or mandibular (Max-Man) and anterior or posterior tooth area (A-P), the depth of gingival cuff (DC) and the interval time between secondary operation and final restoration (TI). Correlations between these factors and pain intensity were explored by linear regression analysis and a multivariable linear regression model was established. Results 38 patients with 82 Dentium implants were included in this study. DC and TI had statistically significant correlation with the pain intensity and were introduced to establish a multivariable linear regression model. Max-Man and A-P had no statistically significant correlation with the pain intensity. In the established multivariable linear regression model, the predictors had no collinearity; sample influential points were absent, and the residual distribution had normality and equal variances. Conclusion DC and TI have significant association with the pain intensity during seating implant abutments. Thus, the established multivariable linear regression model is reliable.

Objective To investigate the clinical feasibility of immediate loading in edentulous patients and evaluate the clinical effect of treatment. Methods 22 edentulous patients from January 2012 to March 2015 were enrolled. Totally 140 implants were inserted and were immediate loaded within 48 hours by fixed provisional prosthesis. Then, the permanent restorations were performed 4 to 6 months later. Afterwards, survival rate of implants, marginal bone absorption level, implant stability, condition of gingival tissue around implants and degree of satisfaction of the patients were observed and evaluated. Results A total of 140 implants were loaded immediately. Three implants failed and the survival rate was 97.9% (137/140). The average marginal bone absorption was (0.62±0.11)mm in six months and (0.74±0.13)mm in twelve months. During the follow-up period, mechanical complications occurred in 4 patients, such as provisional prosthesis fracture, relining, the artificial teeth crack and so on. Healthy gingival tissue around implants was seen. The dentures were stable and function of chewing was restored well. Patients were satisfied with the clinical treatment. Conclusion Choosing appropriate cases, the immediate loading in edentulous patients using surgical and restorative techniques is predictable. An ideal and reliable clinical efficacy can be obtained in the short and medium term.

Objective To investigate the clinical effect of corticotomy assisted orthodontic treatment. Methods 48 orthodontic patients were selected, 14 males and 34 females, and they all accepted corticotomy assisted orthodontic treatment. Corticotomy had been used in the clinical treatment: auxiliary arch expansion, extraction of anterior teeth retraction, molar anterior displacement, traction crown, root bone adhesion teeth mobile, etc. Results Corticotomy could remove the cortical resistance, accelerate the orthodontic tooth movement, increase the periodontal support tissue and bone cover, reduce the root resorption, and enhance the stability of the treatment. Conclusion Corticotomy assisted orthodontic treatment can not only accelerate the tooth movement, but also effectively solve some difficult problems of the orthodontic treatment.

Objective To evaluate the clinical effects of all-ceramic restoration with chairside CAD/CAM system (CEREC ACTM). Methods A total of 667 large CEREC ACTM single-tooth all-ceramic restorations were fabricated to restore different tooth defection in 619 patients. After 1 year 603 teeth from 597 patients were reevaluated according to modified USPHS criteria regarding aesthetic properties, e.g., “anatomic form”, “color match”, “marginal discoloration” and “surface roughness”; functional properties, e.g., “marginal integrity”, wear include “proximal contact” and “static/dynamic occlusal relationship”; and biological properties, e.g., “tooth vitality” and “secondary caries”. Results The clinical follow-up showed that survival rate was 95.11% in our study. In these failure cases, bulk fracture of all-ceramic restorations still accounted for well up 83% of the total. 93% of the restorations revealed sufficient ratings for esthetic properties. 82% of the restorations maintained favorable ratings for functional properties. No biological complications, for example, caries, hypersensitivity, were observed. Conclusion The sufficient rating of modified USPHS criteria demonstrates that all-ceramic chairside CAD/CAM (CEREC ACTM) generated restorations in clinical performance are favorable. Therefore, long-term follow-up studies are needed to assess the clinical effects of all-ceramic restorations with chairside CAD/CAM system.

Objective To observe sella turcica morphology of 3-24 year-old orthodontic patients in northeast of China, and analyze the changes of sella turcica in different age periods, and provide evidence for clinical diagnosis and application. Methods One thousand seven hundred and fifty eight patients were chosen from orthodontic department, stomatology hospital, China Medical University, from 2008 to 2015. The length, depth and maximum diameter of the sella turcica were investigated by lateral cephalograms. The changes of sella turcica were analyzed in different age periods. The SPSS17.0 statistical software was used for the data analysis. Results During growth, the length, depth and maximum diameter of the sella turcica had gradually increased with age, and the sella turcica morphology remained stable after 18 years of age. Length and depth of the sella grew constantly and slowly. However, there was a peak in the changes of maximum diameter, 12 to 16 years old in male and 10 to 14 years old in female. Conclusion The results presented in this study have shown that the sella turcica morphology increases with age, and there is a peak in the changes of maximum diameter.

Objective To evaluate the efficacy of the autogenous dentin particles combining PRF in treating class Ⅱ furcation involvement. Methods 32 patients without systemic disease but with mandibular first molar class Ⅱ furcation involvement, who had been treated through initial therapy were selected. In the experiment group, 16 patients with 16 teeth, the autogenous dentin particles and PRF were placed in the areas with furcation defect, while in the control group, another 16 patients with 16 teeth, Bio-Oss and collagen membrane were used. The patients were followed up at 3,6,12 months after operation. The efficacy was evaluated with clinical parameters and X-ray examination. Results The following periodontal indexes including PD,AL,HPD significantly decreased in both groups after operation(P＜0.05) The alveolar bone density obviously increased in two groups(P＜0.05). Conclusion The clinical effect of the treatment on class Ⅱ furcation involvement by autogenous dentin particles with PRF is remarkable.

Objective To investigate the clinical efficacy of CGF(concentrate growth factors)on bone formation and repairation in the treatment of patients suffered from alveolar bone insufficiency. Methods Seventy-six patients aged between 17 and 63, including 45 males and 31 females, who had fovea bone defect of upper incisor or atrophic posterior maxilla and were treated in our clinical department from Jul. 2012 to Oct. 2014, were treated with lateral window sinus floor elevation, immediate implant combined with the application of CGF, or transcrestal sinus floor elevation. Patients who needed Guided Bone Regeneration (GBR) were separated into two groups. ①CGF therapy only; ②CGF combined with bone substitute or autograft. Regular re-examinations were taken 1 week, 1 month, 3 months, 6 months and 12 months after surgery and the patients were checked every 6 months in two years after operation. The characteristics of the healing of the wound, periodontal condition, implants mobility and the patients’ assessment of aesthetic and function of the prosthesis were recorded. Digital radiograph and cone beam computerized tomography(CBCT) were taken to observe the bone regeneration. Results By 22 months’ (6~34 months) follow-up observation on the average, one implant loosed after 6 weeks due to the wound dehiscence, while the rest had good osseointegration discovered by CBCT. The postoperative reaction of GBR applied with CGF was relieved and the success rate was 98.68%. Conclusion CGF can promote wound healing, enhance bone formation and osteointegration and the time of these procedures can also be reduced. CGF can be applied in the implant surgical operation since it is reliable, economical and safe.

Objective To restore posterior tooth defection after root canal treatment with E-Max all-ceramic onlays and evaluate its clinical effect. Methods 72 posterior teeth from 64 cases, which received completed root canal treatment, were restored with onlays. All restorations were cemented with dual-curing luting cement, and were assessed after 6,12,18 months under the modified USPHS criteria. Results 97.2% of the restorations displayed good results and 95.8% of the restorations did not have gingival inflammation. E-Max onlays had good clinical qualities in short-term observations. Conclusion E-Max onlays is an effective way to restore posterior tooth defection after root canal treatment.

Objective To evaluate anchorage methods applied to the patients for the treatment of maxillary impacted central incisors in the early mixed dentition. Methods A total of 11 patients with maxillary impacted permanent central incisors were selected. The patients presented a ClassⅠskeletal base with average vertical proportions, and no obvious asymmetries. CBCT taken before treatment was used to substantiate the diagnosis, the location, appearance, teeth roots and surrounding tissues. Maxillary impacted central incisors were treated with removed or fixed appliances according to different situations after surgical exposure and bonding of a precision attachment. Results Impacted maxillary permanent central incisors were successfully guided to their places in the arch on a non-extraction basis using upper removed or fixed appliances. ClassⅠincisor’s relationship with normal overjet and overbite was achieved. Conclusion It is worthy of saving the maxillary impacted central incisors for the children. They need early treatment to prevent future complications. CBCT is necessary to guarantee the result.

Objective To assess the clinical efficacy of strontium doped bioactive gel(Camgna densensitezer) combined with pulsed Nd: YAG laser on the treatment of dentin hypersensitivity. Methods 156 teeth of 89 cases with dentin hypersensitivity were divided into three groups randomly，and treated with three different desensitization therapies as bioactive glass combined with Nd: YAG laser(52), Nd:YAG laser(control A:49) and Camgna densensitezer(control B:55) respectively.Effectiveness of the three agents on dentin hypersensitivity was examined immediately，one month and three months after the treatment. Result No statistically significant differences appeared in VAS score among three experimental groups after treatment(P>0.05). The effectiveness of the experimental and control groups was similar immediately after the treatment，but significantly higher than laser(A) and Camgna densensitezer group(B)(P＜0.05). The effectiveness of all the agents reduced one or three months later，and experimental group showed better effectiveness than laser and Camgna densensitezer group(P＜0.05，P＜0.01). Conclusion Camgna densensitezer combined with pulsed Nd: YAG laser is an effective desensitizer for dentin hypersensitivity.

Objective To evaluate the efficacy of GTR with the implantation of autogenous dentin particles in treating periodontal osseous defect. Methods 42 patients without systemic disease, but with vertical bone absorption osseous defect who had been treated through initial therapy were selected. In the experimental group, 21 teeth of 21 patients, the autogenous dentin particles and collagen membrane were placed in the areas with alveolar bone defect, while in the control group, another 21 teeth of 21 patients,the Bio-Oss and collagen membrane were used. The patients were followed up at 3、6、12 months after operation. The response was evaluated with clinical parameters of PD, AL and X-ray examination. Results The following periodontal index including PD and AL significantly reduced in both groups post-operation(P<0.05), but the alveolar bone amount obviously increased in two groups. Conclusion The clinical effects of the treatment of periodontal bone defect by GTR with implantation of autogenous dentin particlesor Bio-Oss have no obvious differences.

Objective To investigate the canal morphology of maxillary first premolar using cone-beam CT (CBCT) and to know its generic and variant forms. Methods 106 CBCT images of maxillary first premolar were selected. The images were analyzed with NNT software to investigate the type and distribution of the root canal. Results The canal configuration of maxillary first premolar:typeI 30 cases (8.52％), typeⅡ 92(26.1％), typeIV 225(63.9％), typeVI 3(0.85％), typeⅧ 2(0.56％). Conclusion Understanding the various morphology of the roots and complex root canals of maxillary first premolars, is of great value for the diagnosis and clinical treatment of root canal morphology.

Objective To evaluate the laser aided debonding and the degree of staining of the teeth surface. Methods 30 healthy premolars extracted from January 2014 to January 2016 in our hospital were selected as the research objects. A month later, the teeth were randomly divided into three groups (A,B and C):group A using laser and silicon particles to bracket, group B using bracket forceps, silicon particle, group C was debonded using bracket forceps, tungsten carbide drill, and silicon particle. Results The operation time of statistics in group C was shortened obviously compared with group B. After the removal of the brackets on the three groups of enamel loss statistics, among the three groups in pairwise comparison, the difference was significant, enamel loss in group C significantly increased compared with group A and group B. Before a group of bonded brackets, the brackets were removed and colored in group A. After the removal of the brackets and coloring treatment, the L* value in group B on the tooth surfaces decreased significantly compared with before bonding; compared with the prior to bonding and after debonding, the L* values in group C after coloring treatment increased significantly. Compared with before bonding, after the removal of the brackets, the A* value in group C decreased significantly; after staining, the a* values of the three groups significantly increased. The B* value of group A,B and C significantly increased after shading treatment. After coloring treatment, the △b* value in group B showed significantly positive displacement compared with group A. The SEM showed that the laser assisted debonding caused less damage on the enamel surface after the bracket, which had no obvious color change. Conclusion The effect of the removal of orthodontic brackets and residual agent method with laser assisted is good, which has less impact on the tooth surface, and its operating time conforms to clinical practice, which is not easy to cause tooth restaining, and then, has the value of clinical application.

Objective To give guidance for clinical nursing work，and to analyze and utilize the effects of digital health education on the subsequent visit rate of outpatient children with dental diseases under general anesthesia. Methods The subsequent visit rates of sixty-two cases of outpatient children under general anesthesia from January to December 2015 were collected. The effects of education degree and income level of parents on the subsequent visit rate were compared. Results Parents with higher degree of education and income level paid more visits than those with low degree and income. The digital health education also increased the subsequent visit rate of outpatient children than those with non education. Conclusion The digital health education can significantly increase the subsequent visit rate of children. It can help the parents to establish correct oral health concepts, improve and maintain the efficacy of children.

Immediate implant loading technique has gained its popularity for the short treatment period and good prognosis. This paper will review the clinical application and development prospect of immediate implant loading technique.

Pressure pain threshold (PPT), as a quantitative sensory test, has been used in clinical research on temporomandibular disorder (TMD). It is significant in revealing the mechanism of pain, predicting the procedure of disease and judging the clinical effect difference of different treatments. This article is aimed to review the research progress and limitations of TMD study using PPT.

Dental erosion is defined as an irreversible loss of dental hard tissue by acid etching, which has nothing to do with bacteria.Laser treatment is effective in inhibiting enamel and dentin demineralization and preventing dental erosion. The preventing mechanisms and preventive effects of laser therapy on enamel and dental erosion will be reviewed.