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PURPOSE: To describe alveolar bone thickness in mandibular anterior region of skeletal Class III malocclusion with the help of Cone-beam CT. METHODS: The subjects were selected from consecutive adult patients seeking orthodontic treatment in Shanghai Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2008 to March 2011, which included 64 patients diagnosed to be skeletal Class I malocclusion (Class I group) and 66 patients diagnosed to be skeletal Class III malocclusion (Class III group). Both Class I and Class III groups were divided into 3 divisions respectively according to different vertical facial types. Mandibular left central incisor of each subject was chosen for measurement. The labial (L1), lingual (L2) and total (LO) alveolar bone thickness of skeletal Class III patients in mandibular anterior region were assessed using a CBCT analyzing method with Class I group as the control group. Data was processed with SAS8.02 software package. RESULTS: L1 (P<0.05), L2 (P<0.01)and L0 (P<0.01) of Class III group were thinner than those of Class I group. L1 of high-angle Class III malocclusion was thinner than that of average-angle(P<0.01 )and low-angle (P<0.01 )ones ; L2 of average-angle Class III malocclusion was thinner than that of low-angle ones(P<0.01 )and thicker than that of high-angle ones(P<0.05); L0 of low-angle Class III malocclusion was thicker than that of average-angle ones(P<0.01 ),which was thicker than that of high-angle ones(P<0.01). L1 of Class III group with different vertical facial types was thicker than L2 (P<0.01). CONCLUSIONS: Skeletal Class III malocclusion exhibits thinner alveolus around the mandibular incisor apices compared with Class I malocclusion, which shows strong connection with different vertical facial types. Root apices of mandibular anterior teeth of skeletal Class III malocclusion situated closer to labial cortical bone than lingual cortical bone. It is necessary to access the alveolar bone thickness of adult skeletal Class HI patients in mandibular anterior region before orthodontic camouflage or surgical -orthodontic treatment. Orthodontic camouflage might not be a reasonable treatment alternative for these patients. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the dentofacial manifestation and long term result after orthognathic -orthodontics treatment of Moebius patient. METHODS: A joint orthodontic and orthognathic consultation was performed on 3 moebius syndrome cases. Peri-surgical orthodontic treatment combined with orthognathic surgery and long term follow up (1 ~6 years) was carried out. RESULTS: A severe skeletal open bite was recognized in Moebius syndrome case. Orthodontic combined with orthognathic surgery treatment result in a normal occlusal relationship. A potential post-surgical recurrence was ascribed to functional insufficiency of ascend masticatory muscle. CONCLUSION: Combined orthodontic and orthognathic treatment could correct the skeletal open bite of Moebius syndrome. Routinely postsurgical follow-up was necessary to maintain the long term result. Supported by National Natural Science Foundation of China (81100793), Shanghai Shenkang Research Fund (SHCD12010205) and Program for Innovative Research Team of Shanghai Municipal Education Commission. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the efficiency of ramus implant anchorage for mandibular arch distalization, and determine the feature of tooth movement. METHODS: Six patients were selected to distalize mandibular arch with ramus implant anchorage. Position changes of mandibular first molars and incisors were measured in sagittal and vertical direction to evaluate the amount of molar and incisor distalization and character of tooth movement. SPSS 17.0 software package was used for statistical analysis. RESULTS: The average amount of distalization of mandibular first molar was 4.88mm at crown level and 3.1mm at root level, and of mandibular incisor was 5.02mm at crown level and 1.03mm at root level. All of the lower arches were distalized successfully and achieving normal overjet and overbite. CONCLUSIONS: Significant true distalization of lower arch could be obtained by ramus implant as bony anchorage. The method could be used to correct anterior cross bite and mandibular anterior crowding or flaring without extraction. Supported by National Natural Science Foundation of China (10972142),Research Fund of Science and Technology Commission of Shanghai Municipality(08411961600) and Innovative Research Team of Shanghai Municipal Education Commission. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the treatment result with secondary bone graft and corticotomy of canine at the same time in patients with cleft lip and palate. METHODS: A study was performed in 8 patients with unilateral cleft alveolus who received secondary bone grafting and canine corticotomy simultaneously, the canines were rapidly moved occulsally and labially to the graft region after surgery. The treatment result was evaluated on the photographs, panoramic radiographs, periapical films and bite films taken before surgery, 1 week after surgery and after the canines were uprighted. Grafted bone volume, alignment of root, canine root resorption and gingival margin were compared before and after treatment by pared t test using SPSS 17.0 software package to evaluate the validity and safety of canine movement in grafted bone. RESULTS: Resorption of the bone graft was less than 50%. Roots of the canines in the cleft side and the adjacent teeth were almost paralleled. The difference of gingival margin height between the canines in the cleft and non-cleft side was not significant. Mobility of the canines were mild. CONCLUSIONS: Corticotomy can help the canines in the cleft side move to the dental arch effectively, safely and rapidly with good remolding of its periodontal and endodontic status. Supported by National Natural Science of China (10972142), Research Fund of Science and Technology Commission of Shanghai Municipality(08411961600) and Innovative Research Team of Shanghai Municipal Education Commission. [ABSTRACT FROM AUTHOR]

Initial-boundary value problem to the Stokes approximation equations of compressible flow in one dimension is discussed. When ρ0 ϵ H1 (0,1) , u0 ϵ H01 (0,1), global existence of strong solution to the Stokes approximation equations is proved by compact method. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the usefulness of self-made distraction osteogenesis instrument by orthodontic technique and mini-screw implant anchorage-assisted distraction osteogenesis (DO) to reconstruct partial maxillary defects. METHODS: Eight patients suffering from partial maxillary defects were selected. Their ages ranged from 19 to 43 years and the average age was 33.2 years. There were 5 males. After a special instrument was fabricated, elastic force trifocal distraction was performed by min-implant borne anchorage. Three months later the implants were implanted in the two distracted region and the prosthetic restorations were finished finally. RESULTS: In the areas of distraction osteogenesis, ossifications were fine and prosthodontic technique, and favourable occlusion was obtained. CONCLUSION: Combined orthodontic and DO techniques can reconstruct partial maxillary defect successfully and restore the complicated anatomical contour of the maxilla, especially the dental-alveolar bone. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this study is to compare the different effects of alveolar bone remolding due to retraction of anterior teeth by two types of anchorage mini-screw implant or regular maximum anchorage. METHODS: The sample comprised 26 orthodontic patients with upper dental alveolar bone protrusion and mild crowding. The treatment plan was to remove the four first bicuspids. 14 patients, 3 males, 11 females, aged 20-54 years old (mean: 25 years)were treated with implant anchorage to retract the maxillary anterior teeth. 12 patients, 1 male, 11 females, aged 18-30 years old (mean: 21 years)were treated with regular maximum anchorage to retract maxillary anterior teeth. Lateral cephalograms of all patients were evaluated at two stages: pretreatment, post-treatment. The changes of the long axis of the anterior teeth and dental alveolar were measured. SPSS11.0 software package was used for statistical analysis. RESULTS: The cephalometric findings showed that the anterior teeth were retracted with implant anchorage significantly more than the maximum anchorage, there was no significant difference in the dental alveolar bone remolding between two groups. The first molars moved anteriorly slightly (less than 1mm) with implant anchorage, but significantly (3.08mm) with regular maximum anchorage. CONCLUSIONS: The maxillary anterior teeth are significantly retraced with the implant anchorage; the molars move mesially significantly less in the implant group than the maximum group. There are no significant differences in dental alveolar bone remolding between both groups. Support by Shanghai Leading Academic Discipline Project (Grant No. Y0203) and Research Fund of Science and Technology Committee of Shanghai Municipality (Grant No. 05B224). [ABSTRACT FROM AUTHOR]