Objective:To compare soft-tissue morphology changes by cephalometric measurements be-tween extraction and non-extraction orthodontic treatment in borderline cases.Methods:The samplesconsisted of 33 cases selected as borderline cases by 5 orthodontic specialists.They were divided into 21extraction cases(including 13 four first premolar extraction cases and 8 four second premolar extractioncases)and 12 non-extraction cases by checking patients' treatment records.Conventional cephalometricanalysis was made to compare soft tissue structures before and after orthodontic treatments and the samecomparison was made between two different extraction patterns.Results:No statistical difference wasfound in pretreatment soft-tissue morphology between extraction and non-extraction groups divided fromborderline cases.The PosBs/FH of the four first premolars extraction group was smaller than that of non-extraction group,and the Ns-Sn-Pos of the four first premolars extraction group was smaller than that offour second premolar extraction group.None of the post-treatment soft-tissue measures showed significantstatistical differences between four first premolars extraction group and non-extraction group,but therewere 6 items showed significant statistical differences between four second premolars extraction group andnon-extraction group.Compared with extraction and non-extraction treatments,the most significant soft-tissue changes were:PosBs/FH,LL-SnPos,and Bs-EP.Conclusion:Although pre-treatment soft-tissuemorphology of second premolar extraction group was close to that of non-extraction group,the post-treat-ment soft-tissue morphology of first premolar extraction group became closer to that of non-extractiongroup.Compared with non-extraction treatment,the more significant changes caused by extraction treat-ment were located in the lower lip and chin,but not the upper lips.

OBJECTIVETo analyze effects of non-surgical treatment on subjects of 12-20 years old with severe skeletal Class III deformity and to directly evaluate dental and facial profile changes.

METHODSEighteen patients with severe skeletal Class III malocclusion (male 5, female 13), diagnosed as indication for orthognathic surgery, were included in the study. The average age was 14.6 +/- 2.5 years old., with age range from 12 years old to 20 years old. 12 cases were treated with Tip-Edge straight-wire technique and 6 cases with Begg light wire technique. The average treatment time was 2.5 +/- 0.8 years. The selection criteria included: (1) mesial or superior mesial Class III molar relationship, with maxillary first molar occlude the buccal groove of the mandibular second molars (2) no mandibular shift (3) ANB < -1.5 degrees (4) high angle cases with average value of SN-MP 34.9 degrees +/- 5.9 degrees, 4 cases present with openbite (5) concave facial profile (6) originally classified as surgery cases. Lateral cephalometric films taken at the beginning and the end of the treatment were analyzed with traditional cephalometric analysis. The arithmetic mean (Mean) and standard deviation (SD) were calculated for each variable. Paired t-test was performed to evaluate the significant treatment change.

RESULTSNormal overjet and overbite were established with proclination of upper incisors and retroclination of lower incisors. Inclination of upper incisors was increased 5.9 degrees when measured with the angle of upper incisor to SN plane (P < 0.01). Inclination of lower incisors was decreased 6.6 degrees when measured with the angle of lower incisor to mandibular plane (P < 0.001). Negative value of the distance difference of upper lip and lower lip to Sn-Pg' at the beginning of treatment changed to positive value with significant difference (P < 0.001).

CONCLUSIONSuccessful treatment effects could be obtained with non-surgical therapy in severe skeletal Class III malocclusion in permanent dentition. Remarkable soft-tissue change was noted after the treatment and concave facial profile changed to straight profile.

Adolescent ; Adult ; Child ; Female ; Humans ; Male ; Malocclusion, Angle Class III ; therapy ; Orthodontics, Corrective

Objective To explore the correlation of city school-aged children′s intelligence quotients(IQ) with family factors.Methods Picking up 180 healthy children which aged 10-14 and their parents.Children′s IQ were tested with Wechsler intelligence Scale for Children- Revised(WISC-R).Their parents were investigated by using the questionnaire designed by ourselves about some factors of family which includes Eysenck Personality Questionnaire(EPQ), Home Education Index Measuring Scale (HEIMS),and so on. We analyzed the associations between children′s IQ and family factors with the applicable data about 114 only child. Results Multiple stepwise regression analyses show that some factors have significant effects on IQ of children(P

Objective To explore the neurobehavioral change of mice from dams with human cytomegalovirus(HCMV) infection during first trimester. Methods Eight-week-old fertilized female Kunming mice were randomly divided into infected group and control group.On the 4th gestation day mice in infected group were injected intraperitoneally with 0.5 mL HCMV (1?10-6 50 percent of tissue cultured infective dose),and those in control group were injected intraperitoneally with 0.5 mL supernatant of cultured human fibroblast.Caesarean birth operation was performed on 3 randomly chosen fertilized mice before delivery. Fetuses were observed and their brain tissue were collected and analyzed under light and electron microscope separately.PCR test was used to determine HCMV pp65 antigen of offspring′s sera.Neurobeha-vioral test such as Morris Water Maze and Lashley Ⅲ Water Maze were performed on offspring mice of 6-7 weeks old.Results Compared with control group,the pathological changes such as degeneration,necrosis,and nucleus disappearance of nerve cells and giant cells were found in offspring′s brain of mice in infected group under light microscope. Under electron microscope,swelling of nerve cells and spherical virus particle in the cytoplasm were found in the brain of mice in infected group. HCMV pp65 antigen was detected in 7 offspring mouse′s se-rum in infected group.Offspring′s swimming time and speed were(30.21?12.74) s and(19.10?1.90) cm/s in infected group,while those in control group were (11.87?3.62) s and (23.21?1.02) cm/s by Morris Water Maze test,there were significantly differences between 2 groups (Pa

OBJECTIVETo investigate the relapse of incisor alignment after orthodontic treatment and possible factors which may related to its stability.

METHODS72 finished cases with full records selected from orthodontic clinic of Peking University School of Stomatology composed the sample. The follow-up lateral head films and study casts were taken at least 2 years after orthodontic treatment. The cephalograms were measured by computerized program and the study casts measured by caliper.

RESULTSThe upper Irregularity Index decreased from (11.5 +/- 5.02) mm before treatment to (2.01 +/- 1.39) mm after treatment and then increased to (3.46 +/- 1.69) mm in the follow-up stage. The lower Irregularity Index decreased from (7.24 +/- 44.35) mm before treatment to (1.75 +/- 1.04) mm after treatment and then increased to (3.39 +/- 1.78) mm in the follow-up stage. The changes are significant statistically. The changes of jaw in the sagittal and vertical directions as well as the related changes of the position of lower incisors, the decrease of the lower canine arch width, Bolton Index and sex all have statistically significant relation with the changes of the lower Irregularity Index after retention.

CONCLUSIONSCompared with lower arch, the alignment in upper arch is more stable in the follow-up stage. The results suggest that some possible factors may have correlations with the change of lower arch crowding during the follow-up stage.

Adolescent ; Child ; Dental Arch ; pathology ; Female ; Follow-Up Studies ; Humans ; Male ; Orthodontics, Corrective ; Recurrence ; Tooth Migration

OBJECTIVETo investigate the expression and biological effect of Shh during late bell stage by morphological and semi-quantitative analysis.

METHODSTooth germs were selected from new born Bal b/c mouse (P1, P2, P3, P5, P7). Semi-quality of Shh was measured by Western Blot and the expression place and strength of Shh were observed by in situ hybridization.

RESULTSShh was expressed in the ameloblast layer during late bell stage; the expression strength was high in secretive period and decreased with development; the active N-section was detectable before P3.

CONCLUSIONShh expresses specially in the ameloblast layer in late bell stage, and expression quality is related to the function of ameloblasts.

Ameloblasts ; metabolism ; Animals ; Blotting, Western ; Gene Expression ; Hedgehog Proteins ; In Situ Hybridization ; In Vitro Techniques ; Mice ; Mice, Inbred BALB C ; Tooth Germ ; cytology ; metabolism ; Trans-Activators ; biosynthesis ; genetics

OBJECTIVETo evaluate the effectiveness of mini-screw anchorage on intruding upper incisors in patients with gummy smile.

METHODSSixteen female patients (mean age: 23.8 years) were involved in this study. The mini-screws were placed between upper lateral incisors and canines on both sides for intruding upper incisors together with fixed appliance. The cephalometric analysis was carried out.

RESULTSTotally 63 teeth in 16 patients were intruded successfully and the deep overbite was decreased by (2.74 +/- 2.00) mm (P < 0.001). The distance from the edge of the upper incisor to palatal plane was reduced by (5.00 +/- 2.76) mm (P < 0.001), and the incisors were proclined by (9.34 +/- 10.06) degrees (P < 0.01). The duration for intrusion was 10.8 months on average.

CONCLUSIONSIt was practicable and effective to improve gummy smile by intruding upper incisors with mini-screw implant.

Bone Screws ; Cephalometry ; Cuspid ; Female ; Humans ; Incisor ; abnormalities ; Maxilla ; Occlusal Adjustment ; instrumentation ; methods ; Orthodontic Anchorage Procedures ; instrumentation ; Overbite ; therapy ; Smiling ; Young Adult

OBJECTIVETo evaluate dento-skeletal and soft-tissue profile changes after extraction of lower second molars and treatment using fixed appliances in severe class III subjects.

METHODSFourteen patients with severe skeletal class III malocclusion (male 4, female 10, age rang 12.0 - 17.1 years old, mean age 13.3 +/- 0.8), diagnosed as requiring orthognathic surgery, but rejected surgical therapy were included in the study. Lateral cephalometric films taken at the beginning and end of treatment were analyzed using Pancherz analysis and a traditional cephalometric analysis.

RESULTSAfter active treatment, inclination of lower incisors was decreased 11.7 degrees when measured to the mandibular plane (P < 0.001). A negative value of the distance between upper and lower lip position to SnPg' at the beginning of treatment changed to a positive value (P < 0.001).

CONCLUSIONSThe results of the current preliminary study suggest that success in the treatment of some severe class III deformity in the permanent dentition can be achieved with fixed appliances and extraction of lower second molars. A remarkable soft-tissue change was noted after the treatment and concave facial profiles changed to straight profiles.

Adolescent ; Cephalometry ; Child ; Face ; anatomy & histology ; Female ; Humans ; Male ; Malocclusion, Angle Class III ; therapy ; Molar ; surgery ; Orthodontics, Corrective ; methods ; Tooth Extraction

OBJECTIVETo compare the treatment effect on the prominence of profile in borderline cases between extraction and non-extraction treatment.

METHODSThe sample consisting of 33 borderline cases based on the judgment of 5 orthodontic specialists was divided into three groups according to the treatment way selected by the doctor in charge of the case. Three groups comprised 12 non-extraction cases, 13 four first premolars extraction cases and 8 four second premolars extraction cases. Structure superimposition was used to measure landmarks displacements which reflect the change of profile prominence before and after orthodontic treatment using pretreatment FH plane as a frame of reference.

RESULTSOnly the prominence of upper and lower incisors showed statistically significance between the extraction and non-extraction treatments. There was no statistically significant difference between the extraction of four first premolars and second premolars.

CONCLUSIONThe main effect of extraction vs. non-extraction on profile of borderline cases is the prominence of upper and lower incisors, while their influences on upper and lower base bone and soft-tissue profile are not obvious.

Cephalometry ; Humans ; Orthodontics, Corrective ; Tooth Extraction

OBJECTIVETo investigate the changes of occlusal relationship in posterior teeth among the pre-treatment, post-treatment, and to analyze some possible factors which may relate to the relapse of posterior occlusal relationship.

METHODS29 finishing Class II division 1 cases treated by extraction with full records selected were included. The sample consists of 12 males, 17 females. The follow-up lateral head films and study casts were taken at least 2 years after orthodontic treatment. The cephalograms were measured by computerized program and the study casts measured by caliper.

RESULTSImprovements of molar relationship were shown during treatment and a little bit changes during follow-up. During the treatment, the amount of mesial movement of the lower molars was more than the upper molars in dental Class II malocclusion and the amount was similar between upper and lower molars in skeletal Class II malocclusion although the ANB angle decreased significantly. During the follow-up stage, the movement tendency between upper and lower molars was reversed. The sagittal growth pattern of mandible and irregularity of upper incisors were nearly correlated with the relapse of molar relationship.

CONCLUSIONThe stability of molar relationship is acceptable during the follow-up stage in Class II malocclusion. The improvement of molar relationship depends on the difference of mesial movements between upper and lower molars in dental Class II malocclusion. However, in skeletal Class II malocclusion the improvement of jaw relationship does the effect. The positive growth of mandible and crowding of upper incisors may affect the relapse of molar relationship.

Cephalometry ; Female ; Humans ; Male ; Malocclusion, Angle Class II ; therapy ; Molar ; Tooth Extraction ; Tooth Movement Techniques