【Abstract】Objective the purpose of this study is to investigate the behavior of calcuim and phosphate ions releasing from calcium phosphate cement after immediatly immersed and the affect of cell proliferation of RAW264.7 by CPC extraction. Methods CPC specimens were immersed in DMEM for 1h, 2h, 3h, 6h, 12h, 1d, 2d, 3d. The medium was refreshed at each timepoint. The concentration of calcium and phosphate ions releasing from CPC were detected by resultsinductively coupled plasma optical emission spectrometry，ICP-OES. RAW264.7 were cultured in DMEM medium(group B) and DMEM medium+CPC specimens(group CPC) respectively, the proliferation capacity of RAW264.7 were affected by CPC tested with MTT method. Results In DMEM immersing groups, all the concentrations of calcium in medium-refreshed group were higher than these in medium-without-refreshed group(P＜0.05) after refreshed the medium. The concentration of phosphate got a peak value 4.380±0.019mmol/L at 1h in medium-refreshed group. After that, the precipitation amount decreased obviously, and the 2h phosphate concentration was 1.944±0.109 mmol/L (P＜0.05). The calcium increased slowly at the beginning, reaching the peak concentration of 1.590±0.064mmol/L at 6h, then decreased gradually.The cell proliferation of group CPC reached its nadir which was 67.23% at 1d, but the peak point was 95.93% at 7d. Conclusion The group CPC immersed in DMEM can provide a theoretical base for experiments of CPC extraction in vitro. Proliferation of RAW264.7 wasn't affected evidently by CPC.

Objective: To compare cytotoxicity of Clearfil S3 Bond and other four dentin adhesives to L929 cell with the method of MTT. Methods L929 mouse fibroblasts were exposed to different concentrations ( 12.5%，25%，50%and100%v/v) of Clearfil S3 Bond, Single Bond, Clearfil SE Bond, Xeno Ⅲ Bond, G-Bond for different time(24 h，72 h and 120 h)．The relative proliferation rate of L929 mouse fibroblasts was calculated, and the toxicity was measured and ranked as 5 grades. The data were statistically analyzed. Results After 72 h, 120 h, Cytotoxicity of 12.5% Clearfil S3 Bond and 12.5% Clearfil SE Bond was less than that of other three dentin adhesives. The difference was statistically significant (P< 0.05). Conclusions All these five kinds of dentin adhesives have weak cytotoxicity. Among them, the cytotoxicity of Clearfil S3 Bond and that of Clearfil SE Bond are the least, so they could be applied in clinic safely.

Objective: This study evaluates a new collagen-based synthetic degradable barrier membrane for use in guided bone regeneration. Methods: A new collagen/HA-collagen degradable barrier membrane were embedded in Bama pigs mandibular bone and Bio-gide@ membrane served as reference materials. In Bama pigs, three standardized 8mm×8mm defect was created in mandibular bone. Three groups (collagen/HA-collagen，Bio-gide@, no membrane) were evaluated at 4 weeks. New bone formation was demonstrated by histological analysis. Results: In the Bio-gide@ and collagen/HA-collagen groups, the defects were left incompleted new formed bone filling. In contrast to uncovered mandibular defects, substantial bone healing was observed in defects covered with a barrier membrane. In the non membrane covered case, the formation of bone was unformed in 4 weeks. There were new formed bone under the Bio-gide@ and collagen/HA-collagen membranes. The amount of new bone formed under the Bio-gide@ membranes were more than the amount of bone formed under the collagen membranes. Conclusion: It can be concluded that the collagen/HA-collagen membrane was well suited for use in guided bone regeneration.

Objective To detect the expressions of extracellular matrix metalloproteinase inducer(EMMPRIN) and its ligand cyclophilin A(CyPA) in peri-implant crevicular fluid (PICF) and provide scientific basics for future study on the role of EMMPRIN and CyPA in the pathogenesis and progression of peri-implantitis.Methods PICF of patients with prosthetic implants loading for more than one year (group IM) were collected and assayed for EMMPRIN and CyPA expressions by ELISA.The clinical periodontal status of these patients was examined.The relationships between the expressions of EMMPRIN and CyPA in PICF and clinical parameters together with the difference between group IM and the control group were analyzed. Results In group IM,there were significant positive correlations among PICF volume,EMMPRIN total amount and CyPA total amount.In addition,EMMPRIN total amount was positively correlated with gingival index(GI) and modified plaque index(mPLI),compared to the positive correlation between CyPA total amount and GI. Nevertheless,there was no significant difference between the two groups (P>0.05).Conclusions The expressions of EMMPRIN and CyPA in PICF,which were probably positively correlated with the inflammatory status of peri-implant tissues,were significantly positively correlated with PICF secretion.

Experiment research of antagonistic effects of two probiotics on halitosis pathogens YANG Wenjie，Ye Wei.(Department of Prevention Dentistry，Ninth People’s Hospital，College of Stomatology, Shanghai Jiao Tong University School of Medicine，Shanghai Key Laboratory of Stomatology，Shanghai 200011，China) Abstract: Objective To evaluate the possible antagonistic effects of two probiotics Lactobacillus delbrueckii subsp. bulgaricus（Lb）and Streptococcus salivarius（Ss）on halitosis pathogens Porphyromonas gingivalis （Pg） and Fusobacteriurn nuclearum （Fn）.Methods 1ml suspensions of Lb and Ss were mixed with equal volume and concentration of Pg or Fn respectively. All mixtures were cultured under anaerobic conditions at 37 ℃for 6h，12 h, 24 h and 48 h respectively. Two probiotic bacterial species Lb、Ss were used to rate the competitive exclusion between probiotics and halitosis pathogens Fn and Pg.Result The amounts of Fn and Pg cultured with Lb and Ss significantly decreased compared with those cultured alone (P<0.05 or P<0.01).The competition between probiotics and pathogens depended on the sequence of inoculation. Conclusion The results demonstrated that Lb and Ss all strongly inhibited the growth of Fn and Pg,especially the growth of Pg by their metabolites.

Objective: To explore the influence on micro leakage from root tip and tooth root’s bending strength by different combinations of root canal preparation and filling technology. Methods: 186 extracted teeth were selected and randomly divided into 6 experimental groups (A, B, C, D, E, F group, 30 teeth per group) and positive, negative control group (G, H group, 3 teeth per group). Group A, B, C were given root canal preparation by step-down technique, and group D, E, F were given step-back technique. Subsequently, BeeFillTM 2in1 teeth filling system was used in group A and D to fill root canal, and group B and E were given Cortisomol paste with warm gutta percha fill with vertical compression method, yet group G and H were not given any filling. The dye penetration method was used to measure root tip’s micro leakage, and tooth root’s bending strength was also measured in each group. Results: With the same filling method, the dye penetration lengths of group A, B, C were all less than those of group D, E, F respectively(t=3.29~4.66,P＜0.05), and group A, B, C’s maximum compressive loads were higher than those of group D, E, F respectively(t=3.11~4.50,P＜0.05). With the same preparation methods, dye penetration length in group A was less than that of group B and C(t=3.32~4.77,P＜0.05),and dye penetration length of group D was less than that of group E and F group(t=3.17~4.35,P＜0.05).Group A,B,C’s maximum compressive load decreased successively(F=5.13,P＜0.05),and group D,E, F’s maximum compressive load also decreased (F=4.87,P＜0.05),yet there was no statistical difference in maximum compressive load between group G and H(t=0.00,P＞0.05). Conclusions: The use of root canal preparation with step-down technique, and BeeFillTM 2in1 teeth filling system can effectively reduce micro leakage from root tip and improve tooth root’s bending strength, which has reference value for selection of root canal preparation and filling techniques.

Objective　To analyze the method of ORIF for different types of mandibular condyle fracture. Methods　From January 2011 to March 2014, 46 adult patients with condyle fractures of the mandible were studied. ALL the patients undergone the ORIF of mandibular condyle fractures and were followed up weekly for 3 weeks and then at 2, 3 and 6 months after surgery. The patients accepted CBCT examination 1 week and 3months after operation. Clinical examinations including mouth opening, deviation on mouth opening, occlusion, function of facial nerves, frey syndrome, screw loosing and salivary fistula were conducted. And the satisfaction degree of the patients was checked. Result　No screw loosing salivary fistula and frey syndrome were found in the follow-up patients; facial nerve dysfunction was found in 7 patients (23.91%) all in condyle head and subcondyle fracture group. Facial nerve dysfunction in condyle neck group was significantly lower than the other two groups（p<0.05）.Mmouth opening outcome in all groups significantly improved over time after surgery（p<0.05）.Of the 46 condyle fractures that were associated with deviation on mouth opening were those of condyle head fracture 11 (23.91%), followed by subcondyle fracture 5 (10.87%) and condyle neck fracture 4 (8.70%). 37 of 46 patients expressed high satisfaction degree for the treatment. Conclusion　Appropriate incisions, fixation methods and operations should be chosen for different types of mandibular condyle fractures. For condyle head fracture, it will be better to be fixed with titanium screws and the lateral pterygiod muscle should be remain attached to the fractured medial segment. The patients got good mouth opening and occlusion and gave high satisfy degree for the treatment..

Objective: To describe the radiographic features of odontogenic maxillary sinusitis using cone beam computed tomography (CBCT) scans and to determine whether any tooth was more frequently associated with this disease. Methods: 500 CBCT scans were classified as normal sinus, maxillary sinusitis of an odontogenic origin, maxillary sinusitis of a non-odontogenic origin and maxillary sinusitis of an undetermined origin. Result: Sinusitis of odontogenic origin was recognized if it met the following criteria: carious tooth, tooth with defective restoration, or extraction site with or without radiographically periapical lesion and mucosal thickening limited to the area of the tooth or extraction site in question. 124 maxillary sinusitis with possible odongenic origin were detected, which accounted for 48.6% of all the maxillary sinusitis. Maxillary first molar was most likely to be frequently associated with odontogenic sinusitis. In sinuses in which the thickening was more than 2mm, the mean mucosal thickening was 6.11±4.43mm Conclusion: Among patients with maxillary sinusitis, nearly half of the cases appear to be associated with odontogenic pathology. Maxillary first molar is the most likely to cause odontogenic maxillary sinusitis. The use of CBCT scans can provide the accurate anatomic structure of maxillary sinus and the changes in it.

Objective　 28 cases of immediately planted upper front teeth, soft tissue of which were reconstructed with the transplantation of free connective tissue flap ,were retrospectively analyzed. Methods　28 cases of transplantation of free connective tissue flap of immediately planted upper front teeth were completed by the same dentist between December 2012 and May 2013, in which 28 implants were embedded immediately, with teeth dragged without flap by way of non-burying. In palatal side lobe the flap of isolated connective tissue was cut off and the reconstruction with the transplantation of free connective tissue flap was retrospectively analyzed and studied in order to observe the situation of the survival of tissue flap and the prospect of reconstruction of implant soft tissue after surgeon. Results　Free connective tissue flap healed very well with 96.43% clinical survival rate. In addition, the soft tissue morphology achieved the expected results with higher scores on pink esthetic score (PES), and reconstruction of soft tissue attained the aesthetic effect. Conclusion　The reconstruction of soft tissue which was immediately embedded in upper front single planted teeth is safe and reliable as well as convenient for disc with short surgical time so that it can be viewed as a reasonable choice of the soft tissue reconstruction.

OBJECTIVE: To study the effect of different Insertion torque values on implant stability and osseointegration by using the means of Resonance Frequency Analysis. MATERIAL AND METHODS: 49 patients were chosen randomly according to the following standards, with 86 screws implanted. Furthermore, the same experienced clinician finished all surgeries. All implants were divided into three groups based on the insertion torque values: Group A, Itv0~15Ncm; Group B，Itv20~40Ncm；Group C，Itv>40Ncm. The dental implant stability was measured to evaluate the osteointegration by Resonance frequency analysis when implants were placed immediately and at the time point of 8 weeks and 12 weeks after the surgeries. RESULTS: 1.Compared with the ISQ measured immediately after the surgery, all the values of ISQ at the time points of 8 weeks and 12 weeks after the surgeries were higher. 2.The ISQ at the 8 week time point of Group A showed the most obvious increase; while there was no significant difference among the three groups. 3.The ISQ values showed no significant difference between the 8-week time point and the 12-week time point in all three groups. Conclusion: The 8-week time point is a critical time for implants healing to develop a high- quality osseointegration. What is more, there was no obvious difference that has been observed of the osseointegration at the 8-week time point when ISQ changed among the groups.

Objective　To compare the clinical effects of minocycline hydrochloride and iodine glycerin on peri-implantitis. Methods　Sixty patients with 65 dental implants suffering from dental peri-implantitis were chosen. After scaling, all implants were randomly assigned to 2 groups: local application with minocycline hydrochloride or iodine glycerin. Parameters including plaque index (PLI), sulcular bleeding index (SBI) and probing depth (PD) of pockets were measured at base line, 1, 3 and 6 weeks after treatment. Results PLI, SBI and PD decreased significantly after the two treatments, but the effect of minocycline hydrochloride treatment was lasting longer than the control. Conclusion　Local application with minocycline hydrochloride is effective for dental peri-implantitis.

Objective To study the effects of the removable partial denture on IL-1β in gingival crevicular fluid of the type Ⅱ diabetic patients. Methods Thirty-six type Ⅱ diabetic patients were selected randomly in the dental clinic. After the non-surgical periodontal treatment, removable partial dentures were restored. IL-1β in gingival crevicular fluid were compared between the butment and the counterpart tooth in the opposite side at different time points, including before the restoration and 2 weeks, 3 months, 6 months, 12 months after the restoration. Results IL-1β in gingival crevicular fluid of the butment of the type Ⅱ diabetic patients was significantly higher than that of their counterparts (P<0.01); IL-1β in gingival crevicular fluid of the butment of the type Ⅱ diabetic patients elevated within 6 months after the restoration (P<0.01);There was no significant change of the IL-1β between the 12th month and the 6th month. Conclusion The removable partial denture restoration leads to the increase of the IL-1β in gingival crevicular fluid of the butment of the type Ⅱ diabetic patients.

Objective In this study, spiral CT is applied in the measurement of crown facial prominences among people in Hohhot Mongolian school, from which we get the mean and the standard deviation of normal occlusal crown facial prominence. At the same time, the differences of the crown facial prominences can be determined through the comparative study between men and women. Methods 60 students with normal occlusion are selected in Hohhot Mongolian school, among which males and females are each half and age from 16 to 22. The upper and lower jaws of the selected samples are scanned by the GE64 -slice spiral CT machine, and data was analyzed by the Aw 4.4 resetting working station and 3D figures were reset with software to measure the crown facial prominence. Results U1、U 2、U 3、U 5、U 6、U 7、 L1 and L2 are statistically meaningful among people between males and females. Conclusion In orthodontic treatment , correctional quantity should be different between for Mongolian males and females .

Objective To establish a thermal and mechanical quantitative sensory testing (QST) profile at intr- and extra- oral sites and hand and test the site, gender and age differences in healthy Chinese. Methods twenty young subjects and twenty aged subjects participated the study. Cold detection threshold (CDT), warm detection threshold (WDT), cold pain threshold (CPT), heat pain threshold (HPT), mechanical detection threshold (MDT) and mechanical pain threshold (MPT) were measured at four sites: the surface of left hand (Hand) ), the skin of the mental foramen (Chin), the tip of the tongue (Tongue), the mucosa of lower lip (Lip). Statistical analysis was performed using ANOVA with repeated measures to compare the means within and between groups. The bonferroni tests were used to calculate the post-hoc comparisons. Results A significant site effect was observed for CDT, WDT, MDT, and MPT (P＜0.01).There were significant age differences with significantly lower sensitivity for WDT (P＜0.01）, MDT (P＜0.01) , MPT (P＜0.01) and CDT (P=0.01) in the aged group compared to young group. A significantly higher sensitivity for CPT (P＜0.01) and HPT（P=0.03) were detected in women compared to men. Conclusion Application of this thermal and mechanical quantitative sensory testing provide some information for a better understanding of the underlying mechanisms of somatosensory phenotypes and for the better further study of sensory dysfunctions in the intr- and extra oral trigeminal area in healthy human . Key words: quantitative sensory testing(QST); trigeminal system; craniofacial pain

Objective　To investigate the character of iconography, classification and treatment in sagittal saw fracture of maxilla. Methods　The maxillary bones were measured with 3-dimensional (3D) CT to distinguish the types of fracture and therapy. Results　The study group consisted of 42 patients with maxillary bone fracture. Types Ⅰ: 30 cases of sagittal saw fracture line from palatine process, alveolar process to basis nasi, and they always had maxillary bone transverse fracture. TypesⅡ: 8 cases of fracture line from palatine process, alveolar process and basis nasi to orbital wall. Types Ⅲ: 4 cases of fracture line from palatine process, alveolar process upwards through maxillary bone surface and arrived paries inferior orbitae, and 4 patients have shown occlusal premature contact and interdental space gap has appeared in 3 patients. Conclusion　The maxillary bone sagittal saw fracture could appear in the center or by center's side and there are three types in iconography. TypesⅠ,the fracture lines from palatine process, alveolar process upwards to basis nasi or piriform aperture border and they always had maxillary bone transverse fracture. TypesⅡ, the fracture lines from basis nasi, piriform aperture border or frontal process to paries inferior orbitae or paries medialis. Types Ⅲ, the fracture lines from alveolar process upwards through maxillary bone surface and arrived paries inferior orbitae.

Abstract: Instrument separation mainly refers to the endodontic instruments fractured in root canal or beyond the apex by accident in the process of root canal treatment. Such an error prevents the achievement of efficient cleaning and shaping, which in turn possibly results in the failure of the treatment. The aim of the following review was to analyze the literature assessing the endodontic instrument fracture, focusing on its incidence, prevention and treatment.

Abstract: Rheumatoid arthritis (RA) and Ankylosing spondylitis (AS) are both rheumatoid osteopathic diseases，which are also autoimmune diseases. The prevalence of rheumatoid osteopathic disease is increasing in people suffering from periodontitis and vise versa. The mechanism of periodontitis and rheumatoid osteopathic disease is similar. We explained several aspects of the relationship between rheumatoid osteopathic disease and periodontitis, which emphasized the pathogenesis for inflammatory lesion and destruction of bone. Hereby, multi-disciplinary study is vital and can provide theoretical foundation for periodontal lucubration.

【Abstract】　Dental caries is one of the most common bacterial infections, which is mainly caused by Mutans Streptococci. Effectively inducing the organism to produce systemic immunity and mucosal immunity against Mutans Streptococci, thus preventing bacterial adhesion and aggregation in the tooth surfaces and bacterial colonization in the oral cavity, is an effective way of preventing cariogenic bacteria infection. Immunization against dental caries mainly includes active immunization and passive immunization. The advantages and disadvantages, research progress and future prospects of Anti-caries DNA vaccine are mainly discussed in this article.