Objective To study the expression pattern of Klf4 in human dental pulp and fibroblasts in vitro. Methods Immunofluorescence was used to obtain the expression of Klf4 and Ki67 in human dental pulp and fibroblasts in vitro. Reverse transcriptase-polymerase chain reaction was used to detect the mRNA expression of Klf4 in human dental pulp cells and inducing mineralization on day 14. Results In human dental pulp,the expression of Klf4 was positive in odontoblasts and vascular endothelial cells; in fibroblasts in vitro, the expression of Klf4 was up-regulated in inducing mineralization on day 14. Conclusion Klf4 was specifically expressed in odontoblasts, and it may be correlated with the differentiation of odontoblasts.

Objective To evaluate the effects of microimplant anchorage combined with casting appliance on the intrusion of extruded upper second molars. Methods The 8 cases were 24-52 years old. They had lost one lower second molar for a long time, which resulted in protruded upper second molars and no space for restoration. Micro-implants were used as absolute anchorage and casting appliances as the force transmission system. The power chain was the tool to intrude prolonged molars. Results The average intrusion of the eight cases was 3.2 mm. The achieved vertical space was enough for the restoration. Denture restoration was completed. The average treatment period was 5 months. There was no obvious root resorption、pulp necrosis and teeth loosening. Conclusion Combination of microimplant anchorage and casting appliance is a useful force system to intrude protruded upper second molars.

Objective　To explore the clinical features and treatment of condylar fractures. Methods　Clinical data including causes of injuries， treatment and efficacy of 179 patients with condylar fractures from 1990 to 2010 were retrospectively analyzed and compared. Results　92 of 179 patients were caused by traffic accidents(51.4%), and 76 cases had condylar neck fracture（42.3%）. 123 cases received conservative therapy and 56 cases received internal fixation surgical treatment from different approaches. The rate of cases who received conservative treatment in youth group was higher than that in adult group（P＜0.01）. Treatment methods of different fracture sites had significant differences（P＜0.01）. The treatment rate of condylar head fracture by conservative therapy was highest (92.06%). When the treatment of mandibular condylar fractures was combined with treatment of bone fractures on other sites, the treatment rate was higher than those not combined（P＜0.01）.Most of the cases acquired perferct occlusion after treatment. Limitation rate of mouth opening of double side condylar fracture cases increased significantly in early period（P＜0.01），which were recovered through functional exercise and reached over 3.0 cm one year later. Conclusions　Traffic accident is the primary risk factor of condylar fracture. Neck is the most frequent site of condylar fracture. Youth group mainly take conservative therapy. Cases combining fractures on other sites mostly choose surgicaltreatment. The angle of fracture end displacement in surgical treatment is more than 30 °, and vertical height of mandibular ramus reduce by more than 5 mm. It’s important for cases to have limitation of mouth opening less than 2 cm after conservative therapy.

Objective To discuss the clinical application of the removable appliances in traction of subgingival root extrusion of anterior teeth . Methods 10 subgingival roots of anterior teeth with crown-root fracture of 6 cases were selected. After complete root canal therapy had been finished, the traction was implemented with maxillary removable appliances. The scaffolds of the removable appliances were bended with the 0.8mm stainless steel wires, which were against the mesial surfaces of the adjacent teeth and parallel to the long axess of the subgingival roots. Finally, sections were exposed at the position 5.0mm above or flush with the gingival margins. Results All the 10 roots were 3.0-5.0mm above the gingival margin. After crown restoration, 1 root was loose byⅠ°, and the other 9 roots were satisfactory 12 months later. Conclusion Active orthotic devices are simple and feasible for traction of subgingival root extrusion of anterior teeth.

Objective　 Deciduous root canal morphology was complex and difficult to acquire complete samples. This study made preliminary research on the root canal morphology of deciduous molars by CBCT. Method　The images were from radiology department. CBCT imaging system was used to examine for root canal morphology of maxillary and mandibular first and second deciduous molars. Result　207 children were examined by CBCT. All maxillary first deciduous molars had three root canals. 80.31% of the maxillary second deciduous molars had three canals, while 19.18% had four canals and 0.51% had five canals. Of mandibular first deciduous molars, 7.03% had two canals, 46.62% had three canals, and 46.35% had four canals. Of mandibular second deciduous molars, 3.95% had three canals and 96.05% had four canals. Conclusion　 Root canal morphology of deciduous molars is complex, and serious examination is needed in clinical diagnosis and treatment.

[Abstract] Objective To explore the effect of metronidazole controlled release pellicles and minocycline hydrochloride sustained-release agent on the treatment of chronic periodontitis. Methods 82 cases with chronic periodontitis were randomly divided into A group (metronidazole controlled release pellicles) and B group (minocycline hydrochloride sustained-release agent).The following indices were analyzed between both groups: general parameters [probing depth (PD), attachment level(AL), plaque index (PLI) and sulcus bleeding index (SBI)] and inflammatory cytokines in gingival crevicular fluid [interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α)] before treatment, and 1week, 1 month and 3 months after treatment, as well as collagenase II activity (COL-Ⅱ) before treatment and 1 week, 1 month and 3 months after treatment. Adverse reaction was also analyzed between two groups. Results The number of cases cured in Group B was more than that in group A (P <0.05) 1 month after treatment, but the total effective rates was not different between two groups. Apart from PD 1 month after treatment, the general parameters, the inflammatory markers and COL-Ⅱ activity of gingival crevicular fluid of B group 1 and 3 months after treatment were better than those of A group ( P<0.01, except IL-6, IL-8 one month after treatment and PD, AL(P<0.05)). There was no significant difference in adverse reaction between two groups（P>0.05）. Conclusions The total effective rates of metronidazole controlled release pellicles and minocycline hydrochloride sustained-release agent on periodontitis were similar, but the long-term effect and inflammatory markers of gingival crevicular fluid and COL-Ⅱ activity of the latter was superior to the former.

Abstract：Objective To evaluate the clinical effect of the orthodontic treatment after extracting two mandibular premolars in adult skeletal cross-bite subjects. Methods Eighteen borderline adult skeletal cross-bite cases from 18 years old to 30 years old were studied. In these cases, first or second mandibular premolars were extracted. Lateral cephalometric radiographs were taken before and after treatment for analysis of all indicators. Results At the end of the treatment, normal overjet and overbite were established in class Ⅲ molar relationship and classⅠcanine relationship. There appeared to be no significant hard tissue changes (P≥0.05). L1-MP angles decreased by 8.1°on average, U1-L1 angles increased by 7.7°on average, L1-NB angles decreased by 7.3°on average, L1-NB distances decreased by 4.8mm on average. Statistically significant differences were found in these changes (P<0.01). The soft-tissue profile improved significantly. Li-E distances, Li-H distances and Li-RL2 distances decreased by 3.2mm、3.4mm and 4.1mm on average respectively. Statistically significant differences were found in these changes (P<0.01). Conclusion Success in the treatment of adult skeletal cross-bite can be achieved clinically by extraction of 2 lower premolars. All the patients get good occlusion and straight profile tendency.

Abstract: Objective: To evaluate the effects of the combination of OAM and GTR in the treatment of periodontal intrabonydefects. Methods: 46 patients(50 periodontal intrabonydefects)were randomized into two groups of treatment: group A- OAM /autologous bone /GTR (experimental group) and group B- autologous bone / GTR (control group) .The followings were recorded before the operation, 12 weeks and 24 weeks after the operation：periodontal probing depth (PPD)、clinical attachment loss(CAL)、 sulcus bleeding index(SBI) and alveolar bone height（AH）．The effects were analyzed statistically by SPSS12.0．Results: After the operation ,both of the indicators in the two groups were significantly improved than those on the baseline.PPD and CAL in group A were significantly lower than those in group B(P<0.05 at the 12th weeks ,P<0.01 at the 24th weeks)．No significant diference in SBI reduction was observed between group A and B (P>0.05)．CBCT showed that there was new bone formation in bone defect area in both groups, but AH in group A increased significantly compared with group B (P <0.05). Conclusions: The therapy of OAM / autologous bone / GTR is more effective than the autologous bone /GTR therapy in reducing PPD and CAL and alleviating periodontitis．It is concluded that OAM / autologous bone / GTR is the ideal way to treat periodontal intrabonydefects.

Objective To investigate the enamel demineralization in the application of orthodontic fixed appliance. Methods Select 78 cases adopted orthodontic fixed appliance in Department of Orthodontics in our hospital from June, 2010 to June, 2011. Analyze the overall condition of enamel demineralization and enamel demineralization (demineralized tooth number, demineralization rate, demineralization degree, demineralization index) in different tooth position after correction. And in the course of treatment, they were divided into one group ( no less than 3 times per day) and the other group (less than 3 times per day) according to the average frequency of tooth brushing to analyze the influence of toothbrushing frequency on soft scale index and demineralization index. Results ① In 1726 teeth from 78 cases, 54 cases (178 teeth) had enamel demineralization. The incidence rate and demineralization rate were 69.2% and 10.3% respectively. The average demineralization index was 0.032±0.029.② Among the 1726 teeth, 1548 teeth (89.7%) belonged to demineralization degree zero; 111 teeth (6.4%) belonged to demineralization degree I; 59 teeth (3.4%) belonged to demineralization degree II; 8 teeth (0.5%) belonged to demineralization degree III. ③The top three teeth that had the biggest demineralization rates were upper lateral incisors（19.9%）, upper central incisors（14.1%）and the lower lateral incisors （12.2%），while the teeth that had the lowest demineralization rate were the first molars（4.5%）. ④There was no difference between the two groups in dental soft scale degrees before treatment. After treatment, the dental soft scale degrees of the two groups decreased obviously. The group (toothbrushing frequency ≥ 3 times / day ) decreased more obviously (P < 0.05 ). There was no obvious difference between the two groups in demineralization index before treatment, the demineralization index of the two groups rose ovbiously after treatment, and the group (toothbrushing frequency ＜ 3 times / day ) rose more obviously（P＜0.05）.Conclusion The incidence of enamel demineralization in the application of orthodontic fixed appliance is high, especially to the incisors (except the lower central incisors ). Related prevention and timely treatment need to be strengthened.

Objective The study investigated an effective method of fabricating a biomimetic micro/nano structure similar to natural alveolar bone on dental implant surfaces in order to improve dental implants’ biocompatibility, osteoinductivity, and to provide a new idea to enhance implant success rate clinically. Methods According to the sizes and features of micron-scale structure (haversian system) and nano-scale structure (collagenous fibril) in natural alveolar bones, a composite biomimetic structure, i.e. micro-pit interlaced self-assemble TiO2 nanotubes on the surfaces of dental Ti implants in vitro was developed by double acid treatment and constant potential anodization. Results This micro/nano surface can provide larger surface energy, preferable roughness and hydrophilicity as compared to smooth mechanical surface and micron-scale counterparts (P<0.01). Conclusion This bioinspired micro/nano fabrication on dental implants’ surfaces brings about good performance for implants, and is more preferable for osseointegration of implants, so as to provide a new strategy for improving implant success rate. It reduces risk, and is safe, reliable, economical, practical. It can obtain good results, so it's suitable for further clinical research and promotion.

Objective Evaluate the sealing ability of BeeFill -TM- 2in1 hot gutta-percha root canal filling system Methods Fifty freshly extracted singled-root human teeth were prepared with NiTi rotary instruments till they reached uniform standards. The teeth were then randomly divided into 2 groups(n=25): group A:BeeFill -TM- 2in1 hot gutta-percha root canal filling system; group B:cold lateral compaction technique. The simples were immersed in methylene blue dye solution and split longitudinally and the lengths of dye penetration were measured on digital images obtained under microscope at ×20 magnification. Results The average leaked length in group A was （0.78±0.13）m. The average leaked length of group B was（1.96±0.46）mm. There was significant difference between group A and group B (p<0.05). Conclusion BeeFill -TM- 2in1 hot gutta-percha root canal filling system shows better sealing ability compared with cold lateral compaction technique. It is suitable for clinical practice .

Objective To evaluate the effects of continued or intermittent irradiation from the diode laser to the root canals in different power, observe temperature changes on the root surfaces in three different irradiation modes. Methods Part 1: a total of 60 single-root human teeth were divided into tow groups, A(power is 1.5w) and B (power is 3 W ). Every group was divided into three subgroups(A1/A2/A3) with 10 teeth in each. Use three different irradiation modes, A1: irradiating for 5 s for 4 times with time interval of 5s, A2: irradiating for 10s for 2 times with time interval of 5s, A3: irradiating continuously for 20s. The temperatures of root surfaces were recorded. Part 2: a total of 30 single-root human teeth were divided into three Groups. Continued irradiation for 20 s was made in power of 1.5 W. Temperatures on three spots of the root surfaces were recorded, G1(apical spot), G2(apical third spot), G3(middle third spot). Results: In group A, A1,A2, and A3 were dealt in different modes, and temperatures increased averagely by 4.78 ℃, 5.21 ℃,5.97 ℃. No significant difference was shown among the three groups. Group B was dealt under the same irradiation condition. The average temperature increase was higher in B than that in grup A. The highest temperature reached 10.3 ℃ in A3. Under the same irradiation condition, the temperature was obviously lower on apical spot(G1) than on apical third spot (G2) and on middle third spot(G3) (P< 0.05). No significant difference was found between G2 and G3. Conclusions The modes of irradiation and power of irradiation both have significant effects on temperature changes on the root surfaces. Changes were different on different spots. The three irradiation modes in power of 1.5 W are all the safe parameters in clinical use.

[Abstract] Objective To evaluate the difference in cleaning degree of the root canal walls of the mandibular incisors between labial access opening and lingual access opening. Methods 18 pairs of extracted mandibular incisors were randomly divided into group A and B. In each pair of teeth, perform labial access opening and lingual access opening separately on the two teeth to prepare root canals, and use nickel-titanium instruments for group A, stainless steel instrument for group B. Then observe the cleaning effect of the root canal walls under the scanning electron microscopy（SEM）. Results ①The cleaning effect of root canal walls in all groups was the crown 1/3>middle 1/3> apical 1/3.②In the crown 1/3, there was no significant difference in the cleaning effect of root canal walls among the groups (P>0.05).③In the middle 1/3, group B with lingual access opening was the worst(P<0.05), and there was no significant difference among other groups(P>0.05).④In the apical 1/3, group A was superior to group B(P<0.05), and group B with lingual access opening was the worst(P<0.05). Conclusion The labial access opening contributes to improving the effect of root canal preparation of the mandibular incisors, combining nickel-titanium instruments to achieve the best effect

Objective　To evaluate clinical results of obturator prosthesisby applicating telescopic crowns and attachments in the repair of unilateral maxillary defects.Methods　Makeobturator prosthesisretented by telescopic crowns and attachments for 17 patients whose maxillary defected caused by tumor ,from June 2006 to June 2011. Masticatory efficiency and speaking functions before repairation and one month later were determined and compared with. Results　Masticatory efficiency and speaking functions were significantly increased after one month. The self evaluation of clinical effect was excellent. Conclusion　Maxillofacial prosthesis retented by telescopic crowns and attachments is an efficient method to repair unilateral maxillary defects.

[Abstract] Objective To compare curative effect of two acid corrosion caking agent in the treatment of teeth feel allergy and anti-allergic medicines Jiguning. Methods 270 teeth on hypersensitive were randomly divided into three groups, and treated by three medicines seperately. They were observed after treatment immediately, 1 months of clinical curative effect, and were followed up for 6 months of forward curative effect. Results After treatment immediately, 1 months G - BOND group and I - BOND group and routine drug compared to the difference between groups was statistically significant (P > 0.05). But in one month after treatment, G - BOND group and I - BOND group of forward curative effect is more ideal, the total effective rate decline in value is less than that in control group (P < 0.05). Conclusion G - BOND group and I - BOND group of recent curative effect affirmation, forward curative effect is relatively ideal, with the passage of time the clinical curative effect for longer

Abstract：Objectives This research used training muscle therapy (MFT method) to treat a case of maxillary protrusion to get rid of bad oral habits and further evaluate the clinical effects of MFT method. Method We chose a patient with maxillary protrusion who visited Orthodontic Clinic of Okayama University. The patient agreed to participate in this study. Result After treatment, the maxillary protrusion was improved obviously and the original joint elastic clicking disappeared. Conclusion MFT training method has important clinical significance for maxillary protrusion caused by insufficient oral muscle strength, tongue sucking and so on.