Objective To investigate the efficacy of plasma exchange in treating chronic fulminaut hepatitis.Methods 226 patients with fulminaut hepatitis were treated by plasma exchange at the base of conventional treatment and their consequence were compared with other 83 patients who did not receive the PE.Results The levels of the ALB,CHO and PTA in treatment group were higher than the control group,while the levels of ALT,AST,TB,CHE,TNF-α and ET in treatment group were lower than the control group.Conclusion The plasma exchange is an effective treatment for the patients with fulminaut hepatitis.

Objective:To assess the repeatability ( intraobserver comparison ) and reproducibility ( inter-observer comparison) of two different methods for establishing the occlusal plane on digital dental models. Methods:With Angle’ s classification as a stratification factor,48 cases were randomly extracted from 806 ones which had integrated clinical data and had their orthodontic treatment from July 2004 to August 2008 in Department of Orthodontics,Peking University School and Hospital of Stomatology. Post-treatment plas-ter casts of 48 cases were scanned by Roland LPX-1200 3 D laser scanner to generate geometry data as re-search subjects. In a locally developed software package,one observer repeated 5 times at intervals of at least one week to localize prescriptive landmarks on each digital model to establish a group of functional occlusal planes and a group of anatomic occlusal planes, while 6 observers established two other groups of functional and anatomic occlusal planes independently. Standard deviations of dihedral angles of each group on each model were calculated and compared between the related groups. The models with the five largest standard deviations of each group were studied to explore possible factors that might influence the identification of the landmarks on the digital models. Results:Significant difference of intraobserver varia-bility was not detected between the functional occlusal plane and the anatomic occlusal plane ( P>0 . 1 ) , while that of interobserver variability was detected ( P<0 . 001 ) . The pooled experimental standard devia-tion the 6 observers established for the functional occlusal plane was 0 . 2 ° smaller than that of the anato-mic occlusal plane. The functional occlusal plane’ s variability of intraobserver and interobsever did not differ significantly (P>0. 1),while the anatomic occlusal plane’s variability of the intraobserver was sig-nificantly smaller than that of the interobserver (P<0. 001),with a 0. 12° difference value of the pooled experimental standard deviation. Conclusion: When one observer measures a number of digital models, both the functional and the anatomic occlusal planes are suitable as a conference plane with equal repeatability. When several observers measure a large number of digital models,the functional occlusal plane is more reproducible than the anatomic occlusal plane,but the difference is small.

Orthodontics in China has experienced two important stages. At its early stage from 1950 s to 1970 s orthodontics was a division of prosthodontic department in China. There were 3 top professors in this field, who got partly training at one time or another in USA and returned to China working in Beijing Medical College, the Fourth Military Medical University and Shanghai Second Medical College. Among them, Professor Mao of Beijing Medical College was regarded as the father of Chinese Orthodontics. Removable appliance was the main tool at that stage and Prof.Mao brought forward Mao’s Classification of Malocclusion which is still used in China. The rapid developing stage began in the 1980 s when China opened its door to the world. More and more orthodontists got further training abroad and brought back advanced techniques since then. Up to now, we have already had more than one thousand of orthodontic specialists and established its own organization——the Chinese Orthodontic Society (COS), which holds domestic orthodontic meetings and organize its members to attend international meetings. Right now, almost all advanced techniques in diagnosis and treatment are adopted in China, including 3D imaging, self-ligating bracket appliance, and implant anchorage. Chinese orthodontists have started to present or publish papers in international meetings and journals and more than tiat, started to develop new app-liances, such as Driving-Force Straight Wire Appliance, which has shown advantages in treating skeletal Class Ⅲ malocclusion.

Objective:To determine the accuracy of volumetric analysis of teeth in vivo using cone beam computed tomography(CBCT).Methods: The physical volume(Vw) of 24 bicuspids extracted for orthodontic purposes(16 were imaged with the i-CAT and 8 with the CB MercuRay before extraction) was determined using water displacement technique.Corresponding pre-treatment CBCT image data were uploaded into Amira 4.0 for segmentation and radiographic volume(Va).All measurements were performed twice by two observers.The statistical difference between Vw and Va was assessed using a paired t-test.The intra-and inter-observer reliability was determined by calculating Pearson correlation coefficients and intraclass correlation coefficients(ICC).Results: The overall mean Vw of teeth specimens was 0.553?0.082 cm3,while the mean Va was 0.548?0.079 cm3,0.529?0.078 cm3 for observer 1,and 0.567?0.085 cm3 for observer 2.There were statistically significant differences between Va and Vw(P

Objective: To classify the AngleⅠ malocclusion subgroups using lateral radiographic films according to their ordinary coordinates and standardized coordinates converted by general procrusts analysis (GPA), and to compare the two kinds of classifications and their valne in diagnosis of malocclusion. Methods: 946 pretreatment lateral radiographic films of patients with Angle'I malocclusion were chosen and their ordinary coordinates were acquired via soft ware. The ordinary coordinates were then converted into standardized coordinates by GPA. All of the films were classified by cluster analysis and discrimination analysis applying the upper two kinds of coordinates respectively. Results: (1) Twenty one subgroups were identified according to the ordinary coordinates of the chosen films with the total differentiate rate of 92.7% and leave-one-out differentiate rate of 68.4% (Classification A). Correspondingly, 20 subgroups were identified according to the standardized coordinates with the two differentiate rates of 87.8% and 71.9% (Classification B). (2) If the ordinary coordinates were discriminated by Classification B, the total differentiate rate and leave-one-out differentiate rate were 79.8% and 60.2 % respectively. If the standardized coordinates were discriminated by Classification A, the two differentiate rates were 79.8% and 60.2 % respectively. (3) There were some subgroups having the similar form in Classification A and their difference mainly arose from the difference of the patient age, while there were no such subgroups like that in Classification B. (4)The proportion of the largest subgroup in total subjects is 15.9% and there were 8 subgroups having the number of subjects over 40 in Classification A, whilethe corresponding proportion and number of subgroups were 74.7% and 2 in Classification B.(5)Classification A and Classification B were both suitable to classify a new subject, but Classification B was required to standalize all of the subjects onc again, which was very complex, while Classification A was more simplified. Conclusion: Classification A and Classification B are interelated. GPA could concentrate the subjects in cluster analysis, which reduces some influence of the age to the classification, but the process to classify a new subject is very complex. Thus if quick diagnosis is needed in clinics, Classification A should be recommended, but the influence of the age should be noted.

Objective:To investigate the remodeling of alveolar process following anterior teeth retraction. Methods: Cephalograms of pretreatment (T1), posttreatment (T2) and follow-up (T3) of 55 cases with four first premolars extracted were collected as the study samples. All the lateral head films were traced on the acetate. Palate best fit superimposition was used to transfer pretreatment SN to posttreatment and follow-up cephalograms and to evaluate the displacement of upper incisor teeth roots and the remodeling of alveolar bone. The average of the two measurements was processed by SPSS statistical package. Results:The CRE of upper incisor moved backward 1.8 mm(P05) in SN frame of reference. The width of alveolus on the labial side at the same level increased 0.2 mm (P

Objective: To investigate dentoalveolar compensation for vertical craniofacial pattern after orthodontic treatment. Methods:157 post-treatment cases with normal incisor relationships and various vertical craniofacial patterns were studied. Computerized post-treatment cephalometric analysis was performed to evaluate vertical craniofacial pattern and dentoalveolar parameters. Incisor torques were measured from study models. Correlation analysis was performed between skeletal and dental measurements.Results:①There was negative correlation between post-treatment upper central incisor torque and MP-SN angle(P

Objective:To investigate hard-tissue changes in borderline cases with extraction and non-extraction during treatment and follow-up stages.Methods:Five associate professors,who were from Peking University School and Hospital of Stomatology,were asked to make judgment on the cases with full pre-treatment records for discriminating the borderline cases from extraction and non-extraction cases.Fifty-four borderline cases with full treatment records which had been out of treatment for at least 2 years were followed.Twenty-one cases with follow-up records were collected including 8 extraction cases and 13 non-extraction cases.Cephalometric measurements were preceeded in IDAS(Image and Database Analysis System) software program.Results:In extraction group,significant changes of SNB,SNPg in A-P direction and that of ArGo/ANSMe,MP/SN in vertical direction were present during the follow-up stage,while the overjet was stable.In non-extraction group,only decrease of proclination of lower incisor and increase of overjet were present without any skeletal changes during the follow-up stage.In comparison of the two groups,no skeletal and dental changes showed statistically significant difference except for MP/SN and ArGoGn in pre-treatment stage,while dental characteristics in relation to upper and lower incisor(L1/NB,L1-NB,L1-AP,U1-AP,U1/L1) showed statistically significant difference between the two groups after treatment.But in follow-up stage,the skeletal and dental pattern tended to be similar for both groups only except for the proclination of lower incisor.Conclusion:The similarities of skeletal and dental pattern are demonstrated in extraction and non-extraction group before treatment.Dental changes are the major post-treatment changes in the two groups.In follow-up stage,counter-clockwise rotation of mandible is unique in extraction group,which is likely a hepful factor for stability of overjet,while lingual tipping of lower incisor in non-extraction group without skeletal changes may contribute to overjet relapse.

Objective:Cluster and discriminant analysis of the morphological characters of Angle's Class Ⅱ malocclusion was performed using Procrusts standardization.The classification of craniofacial morphology with the help of morphometry and multivariate statistics was also discussed.Methods: A total of 894 class Ⅱ patients were collected from the orthodontic department,Peking University School and Hospital of Stomatology during 1997-2000.Using Procrusts standardization and cluster analysis,the samples were divided into different groups,discrimination equations were then established.Results: The samples were divided into 11 subdivisions by Procrusts superimposition and cluster analysis.Three discrimination equations were established.The accuracy rate of cross-validated grouped cases was 80.17%.Conclusion: Procrusts standardization had certain advantages in morphological classification;cluster analysis could be used in classification of Angle class Ⅱ malocclusion;For different types,the differentiate rate was not the same;the discrimination equations was the foundation for future research.

Objective:This study aimed to observe the differences of tooth inclinations among post treatment good cases of different malocclusions and untreated normal occlusions in order to give references on clinical adjusting of tooth inclinations. Methods:157 post treatment good cases were chosen and tooth inclinations were measured on post treatment casts using YM 2115 three dimensional measurement instrument. The measurement results were compared with those of untreated normal occlusions. Results:The inclination values of upper and lower incisors of Class Ⅰ groups are most close to those of untreated normal occlusions, which of upper central and lateral incisors are 9.6? and 8.7?, and of lower central and lateral incisors are 1.1? and-1.1?. In Class Ⅱ groups, lower incisors are markedly proclined (5.6? and 2.1?) and upper incisors are similar with untreated normal occlusions. In Class Ⅲ groups, upper incisors are markedly proclined (15.2? and 12.1?) and lower incisors are markedly retroclined (-3.7? and-4.9?). Conclusion:In order to achieve normal overjet and overbite, it is necessary to adjust the inclinations of upper and lower incisors when treated Class Ⅱ and Class Ⅲ malocclusions only by the method of orthodontic treatment.