Objective To investigate the effects of different doses of transforming growth factorβ1 on temporomandibular joint osteoarthritis (TMJOA) in rabbit model.Methods 40 rabbits were randomly divided into experimental group (36) and control group (4).Partial disc resection was performed bilaterally in 36 rabbits to induce osteoarthritis．Four weeks later,the right joint was injected with 20 ng,40 ng,80 ng TGFβ1 as 20 ng,40 ng,80 ng TGFβ1 groups，and the left joint with physiological saline as physiological saline group.6 and 12 weeks after injection,6 animals of each group were sacrificed and the condyle was dissected to be scanned by microcomputed tomography (microCT) and stained with safraninO to analyze the three dimensional morphology of the subchondral bone and examine the amountof proteoglycan in articular cartilage.Results Joints in physiological saline group after the surgery showed osteoarthritic changes with decreased amount of proteoglycan in articular cartilage and gradually hardened subchondral bone.6 weeks after injection,all TGFβ1 groups had a higher amount of proteoglycan than the normal group and physiological saline group,and the amount of proteoglycan in 40 ng and 80 ng TGFβ1 groups was higher than that in 20 ng group.At 12 weeks,all TGFβ1 groups had a wellorganized fibrocartilage.There was no difference in the amount of proteoglycan between all TGFβ1 groups,while it was still higher than the normal group.The subchondral bones in all TGFβ1 groups have improved and were similar to the normal group.Conclusions Intraarticular injection of TGFβ1 can effectively promote the cartilage repair and prevent abnormal bone remodeling of the subchondral bone in TMJOA.

Objective To study the effect of pretension of glass fiber on mechanical properties of newly developed glass fiber reinforced lightcured resin composite(FRC) posts.Methods Glass fibers were stretched 0,0.5% and 0.1% respectively.The glass fibers without pretension were used to be the control group.Each kind of glass fibers were mixed into the resin matrix respectively with a 60%,and then were lightcured within a special transparent mold to prepare the FRC specimens.FRC specimens were subjected to a threepoint flexural bending test to establish the flexural module,the flexural strength and fracture loads.Data were analyzed using a oneway analysis of variance and the Tukey HSD post hoc tests (α=0 .05).A field emission scanning electron microscope was used to observe the cross section surface of FRC and the fracture surface of the FRC after threepoint flexural bending test.Results Different pretension rates of glass fibers imposed different effects on mechanical properties of FRC posts.FRC posts with 1% pretension rate presented flexure modulus of (20.40±1.40) GPa,flexure strength of (573.38±29.45) MPa,and flexure load of (180.42±5.88) N,which were statistically higher than the FRC posts reinforced with glass fibers subjected to no pretension (P<0.05).Conclusions Glass fiber pretension can be used to reinforce FRC.

Objective To evaluate the effectiveness of decompression as the initial treatment for odontogenic cysts.Methods Preand post decompression panoramic radiographs of 15 juvenile patients treated for 26 odontogenic cysts were reviewed for reduction parameters.Results The effectiveness of decompression was good in 8 (53.3%) patients,moderate in 6（40.0%）patients and poor in 1 (6.7%) patient.70 out of 93 affected teeth were preserved.Conclusions Decompression is effective in reducing odontogenic cysts.

Objective To construct a threedimensional finite element model of adult craniofacial complex for the further investigation of the feasibility of palatal implant anchorage for RME in adults and the comparative study between the toothborne RME and the boneborne one.Methods Spiral CT was used to scan adult craniofacial complex,and the computer image processing and transcription technique and ANSYS were employed to establish the three dimensional finite element model.〗Results A three dimensional finite element model was successfully constructed,which had great geometrical characters and biomechanical similarity.Conclusions This model precisely reconstructed cortical and cancellous bone as what they really are,which is suitable for biomechanical analysis of RME.

Objective To explore the significance of the application of clinical pathway in the treatment of cleft lip.Methods 316 cases of cleft lip who have received surgical treatment were selected,of which 158 cases were treated as the path group,following the clinical pathway procedure while the other 158 cases were treated as the control group,following the conventional procedure.The hospital day,days before surgery,total hospital costs,drug costs,postoperative complications and patient satisfaction were analyzed and compared.Results There was statistical significance between the path group and the control group,and the hospital day was shorter,the cost was less,the complications were fewer and patients were more satisfied in path group.Conclusions Reasonable and effective clinical pathway can ensure the effect of surgery of cleft lip patients,shorten hospital stay,reduce hospitalization cost and postoperative complications.

Objective To explore the probability of the existence of the mandibular canal branch in retromolar region and its influence on clinical application through cone beam computed tomography (CBCT).Methods CBCT scanner was used to perform mandibular crosssectional continuous thin layer scanning and multiplanar reconstruction on patients to study the distribution and direction of mandibular canal branches in retromolar region.Results Among the total 416 sides of mandibular canal,there existed 79 sides of mandibular canal branch in retromolar region and the rate was 18.99%.The Branches were located above the trunk,and distributed in the distal or inferior area of the mandibular third molar (if there was no mandibular third molar,then branches were distributed in the distal area of the mandibular second molar).Conclusions The probability of the existence of the branch in retromolar region and its distribution and direction obtained from this study is the theoretical basis for clinical oral and maxillofacial surgery.

Objective To provide evidence for diagnosis of unilateral mastication in the early stage by means of the surface electromyography (sEMG) of masseter muscle (MM).Methods 30 subjects with bilateral chewing and 52 subjects with unilateral chewing were measured by means of sEMG.The subjects were instructed to stay at mandibular postural position (MPP) and to make maximum clenching at intercuspal position (ICP) and chewing.The sEMG of left and right masseter muscles were separately recorded.Asymmetry index of masseter muscles (ASMM) was calculated and compared.Results ①ASMM at MPP,during maximum clenching and chewing in unilateral chewing group were significantly higher than those in bilateral chewing group (P<0.01).②There was no statistical difference in ASMM at MPP,during maximum clenching and chewing between the males and the females among bilateral chewing subjects.③In bilateral chewing group,the 95th percentile of ASMM at MPP,during maximum clenching and chewing were 5.66%，10.65% and 12.73%,respectively.Conclusions At MPP,during maximum clenching and chewing,the bilateral symmetry of masseter muscles in unilateral chewing people was obviously less than in bilateral chewing people.

Objective To investigate the effects of changes of serum squamous cell carcinoma antigen(SCCAg) levels on prognosis of oral cavity squamous cell carcinoma.Methods The changes of serum SCCAg levels in oral cavity squamous cell carcinoma patients before and after operation were detected by ELISA.Results The incidences of recurrence or metastasis in patients whose serum SCCAg value <1.5 μg/L before and after operation were 15.6% and 3.1%; the incidences of recurrence or metastasis in patients whose serum SCCAg value >1.5 μg / L before and after operation were 83.3 percent and 95.5 percent; as for the patients whose preoperative serum SCCAg level >1.5 μg / L,their serum SCCAg levels fell and the postoperative SCCAg value <1.5 μg / L,and the recurrence or metastasis rate was 25%.Conclusions Serum SCCAg may be related to the development of oral squamous cell carcinoma,and the results can be used to evaluate the progress of the patient's conditions and the recurrence or metastasis of the tumor.

Objective To evaluate the marginal fit in vitro between selective laser melting deposition basal crowns and cobalt chromium alloy casting base crowns.Methods Twenty working dies were created from a single master die and were used to fabricate twenty copings in each as the following groups:A(selective laser melting deposition basal crowns,n＝10),B(cobaltchrome alloy basal crown,n＝10).All the metal copings were fabricated according to manufacturers.The restorations were seated on the master die,and highresolution digital photographs were taken of the marginal area on all four sides.The vertical marginal gap was then measured using a calibrated digital software program.Analysis of Variance was used to determine the differences using SPSS 20.0 software package.Results The mean marginal gaps were:group A:（48.20±4.61）μm; group B：（77.90±6.26）μm .There was significant difference between two groups.Conclusions The marginal gaps of two different metal copings are clinically acceptable.The selective laser melting deposition copings resulted in smaller marginal gaps than cobaltchrome copings,which shows that the marginal fit of elective laser melting deposition copings is better than cobaltchrome copings.

Objective To investigate anxiety state and its correlativity with personality factors in partially edentulous patients before implantation surgery.Methods Eighty partially edentulous patients (40 men and 40 women),aged between 24 and 74 (with the average age of (45.0 ±12.9)),were randomly selected for this clinical research.The patients were requested to answer three reliable and valid questionnaires :State Trait Anxiety Inventory(STAI),Modified Dental Anxiety Scale (MDAS) and Eysenck Personality QuestionnaireRevised Short Scale for Chinese (EPQRSC) before treatment.Preoperative anxiety states in patients of different genders and different age groups were analyzed.The correlation between personality factors,Statetrait anxiety,and dental anxiety level was also discussed.Results Compared with male patients,female patients showed higher level of anxiety in the SAI and MDAS score evaluation(P＜0.05).SAI and MDAS scores showed statistically significant difference among different age groups (P＜0.05).There was no significant difference in P,E,N scores of different genders in patients (P＞0.05).P score had significantly positive relationship with MDAS score(P＜0.05).E score was negatively correlated with STAI and MDAS scores（P＜0.05）,while N score was positively correlated with them（P＜0.01).Conclusions The partially edentulous patients of different genders and ages show different anxiety states before implantation surgery.There is certain relevance between personality traits and preoperative anxiety.

Objective To research the clinical effects of Forsus appliance on the hard tissue structure of the patients with skeletal mandibular retrusion at the peak stage of development,and to analyze condylar position change in articular fossa in the course of treatment.Methods 18 patients with a skeletal Angle Class Ⅱ mandibular retrusion were treated with Forsus appliance for an average period of 6.8 months.The sagital skeletal and dental changes were analyzed with reference to the lateral cephalograms before and after treatment.Condylefossa relationship changes were evaluated by means of magnetic resonanceimaging during the treatment.Results Table 1 showed that skeletal and dental data changed greatly,especially the mandible.The growth of mandible was promoted by Forsus appliance while the growth of maxilla was inhibited by Forsus appliance.The position of Condyles almost remained unchanged before and after treatment.Conclusions Forsus appliance has an significant orthopedic effect on bones at the peak stage of development and the physiology relationship of condyle and glenoid fossa recovers after treatment.

Objective Todiscuss two kinds of orthodontic technology that caused the gingival invagination and the influence on its occurrence.Methods 75 cases that used straight wire application system (with the first premolar extracted) and 22 cases that used invisible application system were selected and the incidence rate of gingival invagination was compared between two groups.Logistic regression analysis was done with regard to such factors as gender,age,closing the extraction space and the treatment time.Results There was no significant difference inthe occurrence rate of gingival invagination in these two systems.Gender,the time of closing the extraction space and the size of extraction space did not influence the occurrence of gingival invagination while age had the positive correlation with gingival invagination.Conclusions The gingival invagination is not influenced by different methods of orthodontic technology.It might have correlation with age.

Objective To evaluate the outcome of defect filling with allogenic freezedried bone mixed with bone marrow following conservative enucleation of large intraosseous cystic lesions of the mandible.Methods Fortytwo patients with large intraosseous cystic lesions of the mandible were treated by defect filling with allogenic freezedried bone combined with bone marrow following conservative cyst enucleation.All patients were evaluated postoperatively by repeated clinical examination done by the operating surgeon.Radiographic examination was performed using panoramic radiographs taken before operation,immediately after operation,6 months and 12 months after operation.Results Postoperative hemorrhage occurred in one patient.Wound dehiscence occurred in two patients,and the woundhealing was delayed.All patients showed satisfactory healing.The patients were followedup for 1348 months using panoramic radiographic examination.Recurrence was seen in 2 patients with KCOTs.Clinical and panoramic radiographic examination showed no residual or recurrent cyst in the remaining patients.Conclusions We demonstrate successful clinical application of allogenic freezedried bone mixed with autologous bone marrow as an alternative filling material for intraosseous cystic lesions of the mandible after conservative enucleation.

Objective To compare the influence of three different caries treatments,including traditional application of rotary instruments,atraumatic restorative treatment(ART) and chemomechanical method,on children′s dental fear and anxiety.Methods Ninety pediatric patients aged 512 years who suffered from dental caries were randomly divided into different treatment groups：conventional bur caries group,ART group and chemomechanical caries removal group.Dental fear during the treatments was assessed using Facial Image Scale (FIS).Chi square test was performed with SPSS19.0 statistical software.Results he degrees of fear among three groups were significantly different.The group using traditional method had higher rate of fear than other two groups.Conclusions The Atraumatic restorative treatment and the chemomechanical technique are more effective in easing children′s dental fear and anxiety and achieving better physical and psychological health of children.

Objective To study the content and distribution of calcium 50 μm inside down from the enamel surface of normal mandibular deciduous central incisor as well as its correlation with age and caries status in children.Methods Calcium content of 40 mandibular deciduous central incisors was measured at different depths 50 μm inside down from the enamel surface with the Electron Probe Xray Microanalysis.The specimens were divided into groups according to their hosts' age and caries status respectively.The differences of calcium content at different depths and the correlation between calcium content and age as well as between calcium content and caries status were all analyzed statistically.Results Average calcium content of 40 mandibular deciduous central incisors 50 μm inside down from the enamel surface was 38.39±0.92 (wt%) and there was no statistical difference at different depths,among different age groups and caries status groups respectively.There was low negative correlation between decayedfilled tooth and the calcium content at 40 μm depth beneath enamel surface (r=-0.3573,P<0.05),but no other correlations were discovered.Conclusions Calcium content 50 μm inside down from the enamel surface of normal mandibular deciduous central incisors is distributed homogeneously,which has no significant correlation with the age and cannot be used as the single indicator of caries status.

Objective To describe the permanent teeth caries status of 8yearold students in urban areas of Nanjing to provide evidence for health service of caries prevention.Methods A sample of 1 163 8yeaold students from urban areas of Nanjing was chosen and their status of caries was investigated.Results The caries prevalence rate of permanent teeth was 19.86％．Mean DMFY was 0.412．The caries prevalence rate of deciduous teeth was 52.11％．Mean DMFY was 1.772．The caries prevalence rate of the first deciduous molar was the highest which consisted of 45.85％of deciduous teeth caries,followed by the second deciduous molar.The caries prevalence rate was 29.27％.And the filled was only 13.10％.Conclusions The caries prevalence rate and mean DMFT of permanent teeth is relatively high,and the filled rate is at a low level.We should strengthen and promote the oral health education and caries prevention programs.The monitoring and control for the high risk groups should be strengthened.