目的 探讨恒牙列骨性Ⅱ类错牙合拔牙矫治后牙弓形态、颊廊及侧貌的变化情况及其相关性,为骨性Ⅱ类错牙合拔牙矫治提供参考.方法 选取2013-01～2017-12在广西壮族自治区人民医院口腔正畸科接受拔牙矫治的恒牙列骨性Ⅱ类错牙合患者15例,应用X线头影测量技术分析矫治前后患者牙颌颅面结构变化,游标卡尺测量矫治前后上颌模型牙弓长度、宽度的变化,Adobe Photoshop CS6软件测量分析矫治前后患者正面微笑像变化.分析矫治前后颅颌牙面软硬组织,牙弓宽度、长度以及正面微笑像颊廊相关指标的变化情况及相关性.结果 矫治后,患者SNA角、ANB角、U1-NA角、UL-E和LL-E较治疗前降低,NLA角较治疗前增加,差异有统计学意义(P＜0.05);上颌牙弓中段宽度(UPP)、上颌牙弓后段长度(UPD)、上颌牙弓后段宽度(UMM)和上牙弓全段长度(UAD+UPD)指标均减小,与治疗前比较差异有统计学意义(P＜0.05).与治疗前比较,矫治后正面微笑像口角宽度(Ch to Ch)、正面微笑像颊廊宽度之和(BC)及正面微笑像双侧颊廊比率(BCR)水平增加,正面微笑像上颌可见牙列宽度(Va to Va)水平降低,但治疗前后比较差异均无统计学意义(P＞0.05).Pearson相关分析结果显示,UPP变化与BC和BCR变化呈负相关(P＜0.05);UAD+UPD变化与UL-E变化呈正相关(P＜0.05);Ch to Ch变化与U1-NA和UL-E变化呈负相关(P＜0.05);BC变化与SNB角呈正相关(P＜0.05).结论 骨性Ⅱ类错牙合拔牙矫治后牙弓长度变化与侧貌凸度改善密切相关,牙弓中段宽度减少可能会引起正面微笑时颊廊增加.

目的 构建包含不对称摇椅弓的上颌矫治系统三维非线性有限元模型,为探讨不对称摇椅弓作用于牙列的生物力学机理奠定基础.方法 利用上颌骨及上牙列等CT扫描数据及托槽弓丝等实体数据,通过运行三维有限元分析等专用软件,建立包含上颌骨、牙列、托槽、不对称摇椅弓等在内的整体上颌三维非线性有限元模型.结果 建立了含不对称摇椅弓的上颌三维非线性有限元模型,包含160514个单元和242878个节点.结论 建立的有限元模型具有较高的仿真度和良好的几何相似性,为进一步探讨不对称摇椅弓矫治牙合平面偏斜时作用于牙列的力学机理提供了良好的研究手段.

目的 了解恒牙列骨性Ⅲ类错(牙各)患者单纯正畸掩饰性治疗前后(牙各)平面、下颌平面的变化及其相关关系.方法 回顾性分析12例恒牙列骨性Ⅲ类错(牙各)患者的临床资料,其中ANB角平均(-3.33±1.74)°,SN-MP角平均(37.67 ±4.89)°.拔下颌左右第二或第三恒磨牙,配合下颌颊棚区微种植体支抗或多曲方丝弓技术矫治,比较矫治前后X线头影测量指标变化情况,分析矫治前后牙颌颅面变化与(牙各)平面、下颌平面变化的相关关系.结果 矫治后ANB角平均增大(1.79±1.62)°;OPP-FH平均减小(2.83±2.92)°,FH-OP平均减小了(2.25±2.13)°,矫治前后比较差异有统计学意义(P＜0.05);OPA-OPP、FH-MP、SN-MP矫治前后比较差异无统计学意义(P＞0.05).相关分析结果显示,前面高、前下面高变化与下颌平面变化之间存在正相关关系(P＜0.05).结论 恒牙列骨性Ⅲ类错(牙各)患者经过合理的支抗设计,可以得到良好的矫治,患者正侧貌也可一定程度改善,(牙各)平面及下颌平面也可以得到较好控制.

BACKGROUND: Mandibular advancement devices are commonly used in patients with mild to moderate obstructive sleep apnea hypopnea syndrome. But wearing with mandibular protraction appliance makes the mandible in an abnormal position, and inevitably affects the temporomandibular joint (TMJ). As one of the important components of the TMJ, can structural changes of the joint disk impair the TMJ? Are there any differences in the TMJ structure between Angle Class I and Class II? What will happen to the TMJ structure in the Angle Class I and Class II during mandibular advancement? Is there a same law of TMJ changes for Angle Class I and Class II? All of these are undetermined systematically. OBJECTIVE: To compare the changes in the structure of TMJ disk and the differences during mandible advancement between Angle Class I and Class II adult males. METHODS: Forty non-apnea adult males were divided into two groups (n=20 per group), including Class I and Class II groups, according to the Angle’s classification and sagittal skeletal facial type. Each volunteer was scanned by MRI in three positions, including central occlusion (F 0 ), 75% of the maximum mandible advancement (F 75 ) and maximum of the mandible advancement (F 100 ). These indexes that were correlated with morphology of the joint disk in different mandible advancement positions were measured and calculated by MRI, and then analyzed statistically. RESULTS AND CONCLUSION: In F 0 , the ratio of disk anterior displacement in the Class II group was higher than that in the Class I group (P < 0.01). The angle A was decreased as the mandible advanced in both groups from F 0 to F 75 (P < 0.01). The rotational angular dimension was increased as the mandible advanced, and the sizes from F 0 to F 100 were bigger than those from F 0 to F 75 (P < 0.05). Some differences existed in the structure of TMJ disk between Angle Class I and II adult males. In summary, appropriate mandibular advancement may play a positive role in patients with anterior displacement of the joint disk, but excessive mandible advancement is likely to impair the TMJ disk. Subject headings: Temporomandibular Joint; Temporomandibular Joint Disk; Orthopedic Fixation Devices; Tissue Engineering Funding: the Guangxi Medical and Health Proper Technology Research and Development Project, No. S201315-02; the Science and Technology Research & Development Program of Guangxi Zhuang Autonomous Region, No. 1140003B-72 0 Introduction (obstructive sleep apnea hypopnea syndrome OSAHS) !"#$%& '()*+,-./01 23456)* 78 9: ;<=>+?@ABCD E FG [1] HIJ@A#<+AKL# MNOPQRST UHVW XOSAHS YZ[\6]^$_]^`aY ZbcH_]^YZU IJdY.YZe=20> fgh ij YZkl UmnoWpqIJdY.rst< uv wbcx6yz{|}$~€s‚G Xƒ{U „OSAHS Z… †HnoWpqIJdY. #s‡ ˆ[\e ‰ Š‹sIJdY. ŒnoŽW n‘ ’“”•–—˜“[™š ›™œWmžŸ I¡ ¢ £¤¥¦ ¢ § ̈©Ž V a« ¬ ­® ̄°±¤23 [2-4] H́ ‹sIJdY.YZ OSAHSŠ noμ ¶Š· ̧Wp 1o»Io,‡6 1⁄41⁄2 ¥» 3⁄4¿ÀÁÂà ̈ÄnoÅƁ Ç È (1)* ÂÃ2ɚ Ê1ËÌ«ÍÎYZ [5] H ÏÐ <noÑ Wp ҌXÄnoÅÆÓ%M?_Ô !%ˆ —ÕrÖ XÄnoÅÆ Ô!×Ø$%ˆ01 Ù(1Ú; [6] H Û IJÜÝÔÞ@ßà¬sIJd Y.YZOSAHSŠμXnoWpá⎐ £¤ã16… äÕ¦ ¢ åŠæÊXoçNÀÁÂÃÚ;23HVW6 ÅIJdY.YZOSAHSèÅ ÄnoÅÆ×Ø DEé ê 6ë DEPìíXî°ï ‘ Êð ̈TÄno ÅÆ01ñ<òó ôïÅ,H ́õöÑç÷øù 3úøGàûü¦ýàñ<Ÿ ¦ ¢ þA <ÛöÑç÷6ñ à OSAHS (1 ' OSAHS m + [7] Hå Š àX; õö DEU ÄnoÅÆ ô  %  ö [8] H « õö ÄnoÅÆ(1ýàMŽ ˆ×Ø M ˆ× Ø > ¶« ï [9] H noœW  Än oÅÆôï×، % e X ÄnoÅÆÚ;23 ;<ÄnoÅÆ à* X(1 ýàÄnoÅÆ ˆ×Ø ; õö Tang Q, Fang ZX, Zhou Y, Bai B, Huang MF. A magnetic resonance imaging study to compare structural changes of the temporomandibular joint disk during mandibular advancement between Angle Class I and Class II in adult males.. Zhongguo Zuzhi Gongcheng Yanjiu. 2018;22(12):1811-1816. DOI:10.3969/j.issn.2095-4344.0197 P.O. Box 10002, Shenyang 110180 www.CRTER.org 1813 20 90 Ruf MRI !

BACKGROUND: Lingual bracket system is the best invisible orthodontic appliance due to its aesthetics and efficiency, but it is difficult to control anterior tooth torque during the distal retraction of the anterior tooth. Thereafter, lots of studies on maxillary anterior teeth have been conducted, but there is less knowledge about the mechanical characteristics of whole mandible dentition distal retaction. OBJECTIVE: To analyze the biomechanical characteristics of the mandibular anterior teeth distal retracted by sliding method in lingual orthodontic treatment. METHODS: A three-dimensional finite element model was constructed using a series of specialized software based on volunteer's CT data and lingual brackets, including the mandible, alveolar bone, periodontal ligament, dentition (removal of the two first premolars), lingual brackets and arch wire with hooks (located between lateral incisor and canine and 11 mm distant from the arch wire plane). Subsequently, 1.5 N lingual forces through the hooks of first molar (2 mm distant from the arch wire plane) and the hooks between the lower lateral incisor and canine were loaded and the biomechanical characteristics of the mandibular anterior teeth movement during the en-masse retraction were analyzed. RESULTS AND CONCLUSION: The finite element model was constructed successfully, and had a higher geometrical similarity and resemblance of clinical situation. The crowns of lower incisors showed the tendency of lingual inclination and extension, and this tendency was more obvious in the lateral incisors. The canines were buccal and mesial inclination and intrusion. The periodontal stress concentration area was corresponded with the tendency of tooth movement. Therefore, the movement tendency of incisors is still lingual inclination when mandibular anterior teeth distal retracted by a longer hook in lingual brackets system, and there is no distal inclination. Overall, lower incisors are easy to exhibit lingual inclination; the long anterior hooks contribute to the movement of canines, but it is not available for the vertical control of incisors during mandibular anterior tooth distal retraction.

目的:分析舌侧矫治技术不同长度牵引钩条件下,滑动法整体内收上前牙时牙移动的生物力学特征.方法:利用所建立的舌侧矫治技术内收上前牙三维有限元模型,分别于上前牙区牵引钩(长度2～10 mm)和腭侧的微种植钉间加力1.5 N,内收上颌前牙并分析其牙列位移趋势.结果:牵引钩长度在4 mm以内时,均表现为上颌切牙牙冠的腭侧移动趋势,从6 mm开始,中切牙和尖牙牙冠出现唇侧移动趋势,并随牵引钩加长唇倾越明显.结论:随着牵引钩的加长,前牙牙冠的腭侧倾斜移动趋势减小,长牵引钩可能更有利于上前牙的整体内收移动.

BACKGROUND: Mandibular advancement devices are commonly used in patients with mild to moderate obstructive sleep apnea hypopnea syndrome. But wearing with mandibular protraction appliance makes the mandible in an abnormal position, and inevitably affects the temporomandibular joint (TMJ). As one of the important components of the TMJ, can structural changes of the joint disk impair the TMJ? Are there any differences in the TMJ structure between Angle Class Ⅰ and Class Ⅱ? What will happen to the TMJ structure in the Angle Class Ⅰ and Class Ⅱ during mandibular advancement? Is there a same law of TMJ changes for Angle Class Ⅰ and Class Ⅱ? All of these are undetermined systematically. OBJECTIVE: To compare the changes in the structure of TMJ disk and the differences during mandible advancement between Angle Class Ⅰ and Class Ⅱ adult males. METHODS: Forty non-apnea adult males were divided into two groups (n=20 per group), including Class Ⅰ and Class Ⅱ groups, according to the Angle's classification and sagittal skeletal facial type. Each volunteer was scanned by MRI in three positions, including central occlusion (F0), 75% of the maximum mandible advancement (F75) and maximum of the mandible advancement (F100). These indexes that were correlated with morphology of the joint disk in different mandible advancement positions were measured and calculated by MRI, and then analyzed statistically. RESULTS AND CONCLUSION: In F0, the ratio of disk anterior displacement in the Class Ⅱ group was higher than that in the Class Ⅰ group (P< 0.01). The angle A was decreased as the mandible advanced in both groups from F0to F75(P < 0.01). The rotational angular dimension was increased as the mandible advanced, and the sizes from F0to F100were bigger than those from F0to F75(P < 0.05). Some differences existed in the structure of TMJ disk between Angle Class Ⅰ and Ⅱ adult males. In summary, appropriate mandibular advancement may play a positive role in patients with anterior displacement of the joint disk, but excessive mandible advancement is likely to impair the TMJ disk.

目的 了解戴用下颌前移口腔矫治器后阻塞性睡眠呼吸暂停疾病(OSAD)患者的睡眠结构变化.方法 选取行下颌前移口腔矫治器治疗的OSAD患者61例,接受口腔矫治器治疗前后均行多导睡眠图检查.将患者分为治疗后成功组52例及不成功组9例,对两组治疗前后的睡眠分期比率及疗效进行比较.结果 成功组治疗前后S3、AI、HI、AHI、LSpO2、最长呼吸暂停时间比较差异有统计学意义(P＜0.05).不成功组治疗前后AHI、最长呼吸暂停时间比较差异有统计学意义(P＜0.05).两组治疗后呼吸参数AI、AHI、LSpO2比较差异有统计学意义(P＜0.05).结论 戴用下颌前移口腔矫治器治疗成功的OSAD患者深睡眠百分比略有增加.

目的 了解拔牙矫治及相关肌功能训练在改善恒牙列Ⅱ类骨面型患者正畸后微笑美中的作用.方法 20例恒牙期Ⅱ类骨面型患者,在拔牙设计,直丝弓矫治技术应用技术同时,配合相关微笑美肌功能训练.应用Adobe Photoshop CS7软件对矫治前后微笑相进行定点和测量(包括上前牙曲度、下唇曲度、颊廊、微笑宽度、微笑高度、上下前牙暴露量、微笑弧及上唇曲度形态等),应用SPSS17.0软件对矫治前后颅颌面结构及微笑相测量数据进行统计分析.结果 矫治后上前牙曲度增大,颊间隙比率和上切牙比率有所增加,下切牙暴露量减少,与矫治前比较差异有统计学意义(P＜0.05);矫治后理想笑弧和上唇曲度向上的例数明显增加,平坦笑弧和向下的上唇曲度例数明显减少,差异有统计学意义(P＜0.05);矫治后U1-SN角变化与上牙曲率变化呈负相关,SN-MP角变化与颊旁间隙比率变化呈负相关(P＜0.05).结论 恒牙列Ⅱ类骨面型患者拔牙矫治并配合微笑美肌功能训练各项微笑美指标矫治后均有所改善,其中颊廊与面下1/3高度相关,笑弧与上前牙唇倾度高度相关.

Objective The aim of this article is to study the changes of dental and base bone arch after non-extraction orthodontic treatment in subjects with skeletal ClassⅢ malocclusion.MethodsThe sample consisted of pre- and post-treatment models from 23 skeletal ClassⅢ malocclusion subjects who accepted non-extraction orthodontic treatment. The length and width of dental arch and basal bone arch in intercanine area, interpremolar area and inter-ifrst-molar area were measured, then analyzed the correlation between pre- and post-treatment group.Results① The dental length of the anterior maxillary arch(UAD) and the width of mandibular inter-first-molar (LMM) increased (P<0.05), while the dental width of maxillary intercanine(UCC),interpremolar (U1PP,U2PP) and mandibular intercanine(LCC) decreased (P<0.05) after treatment.② The length of maxillary basal bone (UBAL) increased(P<0.05), while mandibular basal bone length(LBAL) decreased (P<0.05) after treatment.③ A positive correlation was found between the changes of dental arch and base bone arch width and length, especially in mandibular canine area, ifrst molar area and maxillary ifrst molar area.ConclusionAfter non-extraction orthodontic treament of skeletal ClassⅢ malocclusion in permanent dentition, the compensatory changes of the dental arch can induce the adaptation of the corresponding regional base bone arch,which is beneift to the effect and stability of orthodontic treatment.

Objective To investigate the characteristics of anterior and posterior occlusal planes of adolescents with skeletal classⅡ malocclusion.Methods 158 cases in skeletal class Ⅱ malocclusion were selected,all the cases were divided into 3 groups according to different vertical skeletal types: the high,average and low angle groups.The measurement items of anterior and posterior occlusal planes and the items related to the craniofacial structures were marked and measured on the lateral cephalograms of patients by Winceph 8.0,and the measurements were analyzed statistically.Results Items of occlusal planes in both anterior and posterior occlusal plan inclination angles,Go-A angle and RAM-I angle of the high-angle group were larger than that of average and Low-angle groups,and the items of average angle group were larger than that of Low-angle group too(P<0.05).Conclusion There are some differences both in the anterior and posterior occlusal planes among adolescent skeletal class Ⅱmalocclusion patients with different vertical skeletal types.The anterior and posterior occlusal planes in high skeletal type are steeper than other vertical skeletal types,and the craniofacial structures have the corresponding characteristics.

目的 建立舌侧矫治技术整体内收上前牙的三维有限元模型,为进一步探讨舌侧矫治技术整体内收上前牙的生物力学特征奠定基础.方法 利用志愿者的CT扫描数据及舌侧托槽等实体数据通过一系列专用软件的运行,建立包含上颌骨、牙槽骨、牙周膜、牙(拔除左右第一双尖牙)、舌侧托槽、有牵引钩(不同长度)的舌侧弓丝及上颌腭侧微种植体在内的整体上颌三维有限元模型.结果 建立了牵引钩长度分别为2 mm、4 mm、6 mm、8mm、10 mm的五个上颌有限元模型,每个模型均包括42个实体模型.结论 所建立的舌侧矫治技术整体内收上前牙阶段具有不同长度牵引钩的整体三维有限元模型,几何相似性强,临床模拟度较高,为后续的模拟加力研究创造了条件.

Objective To compare the differences of the hyoid position between the Class I and Class II sagittal skeletal facial types in adult males and explore the relationship between the hyoid position and the skeletal facial types. Methods 30 adult males with Class I saggital skeletal facial type and 30 with Class II saggital skeletal facial type were collected, and each of them had average vertical facial type. Cephalograms of them were taken and hyoid position-related parameters were measured and analyzed. Results The horizontal distances of hyoid position-except AH-Or, in Class II adult males were shorter than Class I’s ,the differences were statistically signiifcant(P<0.05), while there were no statistical differences in vertical distances of hyoid position between these two facial types(P>0.05). Conclusion There are some differences in hyoid position between the Class I and Class II saggital skeletal facial types with average vertical facial type. Hyoid position in Class II saggital skeletal facial type adult males are in more posterior position.

Objective To investigate the clinical results using the fix appliance combined with myofunctional therapy for improving the smile attractiveness of patients with skeletal malocclusion.Methods 30 patients (11 male and 19 female ,aged from 13 to 34 years old ,average 21.08± 6.67 years old)with skeletal malocclusion were collected. There were 24 cases with classⅡ sagittal skeletal pattern(ANB angle: 5 to 8°)and 6 with classⅢ sagittal skeletal pattern(ANB angle: 0°to -6°). The cases were randomly divided into experimental group and control group, each group had 15 cases, and 26 cases were treated with extraction, 4 cases were treated with noextraction. The cases in experimental group undergone orthodontic treatment combined with myofunctional therapy, the cases in control group with orthodontic treatment alone. The techniques and principles of orthodontic treatments were the same, and the baseline check of two groups was consistent. The frontal smile photographs were taken for each cases before and after the treatment to evaluate the items about the smile attractiveness. All the measurements were analyzed by SPSS 16.0 software.Results There were signiifcant differences in the items of the height of the outermost corner of lip, the smile width and the proportion of buccal corridor in experimental group between before and after the treatment(P<0.05) . The number of patients with ideal smile arc increased and the straight smile arc decreased signiifcantly after the treatment in experimental group(P<0.05). The change of smile index before and after the treatment in control group had no statistical signiifcance (P>0.05 ). After the treatment, there were signiifcant differences in the items of the height of the outermost corner of lip, maxillary gingival display, average mandibular incisal exposure, the proportion of buccal corridor and the shape of smile arc between the two groups(P<0.05).Conclusion Orthodontic treatment combined with smile myofunctional therapy can make the patients with skeletal malocclusion to rebuild the muscular tissues around the mouth with the change of the teeth and jaws synchronously and harmoniously and help the patient achieve attractive smile at the same time.

目的 比较安氏Ⅰ类和安氏Ⅱ类矢状骨面型无鼾青年男性上气道矢状径差异,探讨骨面型对上气道矢状径的影响.方法 选取骨性安氏Ⅰ类及安氏Ⅱ类青年男性各30例,共60例,垂直向均角型,拍摄头颅侧位片,并进行上气道各段矢状径的测量,比较其差异.结果 安氏Ⅱ类青年男性组上气道在腭咽段、舌咽段、喉咽段矢状径测量值的指标小于安氏Ⅰ类组(P＜0.05).结论 安氏Ⅱ类矢状骨面型青年男性上气道结构与安氏Ⅰ类存在某些差异,提示上气道矢状径大小与颅颌结构相关.

目的 初步探讨固定矫治技术结合微种植体支抗矫治成年女性恒牙期骨性Ⅲ类错(牙合)的颅颌牙面结构变化.方法 选择10例成年女性骨性Ⅲ类错(牙合)患者,年龄18 ～39(24.1±5.98)岁,尖牙、磨牙完全近中关系,ANB角平均-6.46°,SN-MP角平均33.47°.用固定矫治技术结合下颌颊棚区微种植体支抗进行矫治,并辅助舌肌进行功能训练.应用SPSS18.0统计软件对矫治前、后头影测量变化值进行两样本配对t检验分析.结果 10例成年女性骨性Ⅲ类错(牙合)患者矫治后SNA角、ANB角、H角、上下唇突距差(Lip-Diff)增大,SNB角、U1-NA角、APDI及LL-Sn ⊥ FH值减少,矫治前后比较差异有统计学意义(P＜0.05).结论 固定矫治技术结合下颌颊棚区微种植体支抗并配合舌肌功能训练可大幅内收下牙列,有效控制下颌平面高度,协调骨性Ⅲ类错(牙合)上下颌骨矢状向不调,改善成人女性骨性Ⅲ类错(牙合)患者的咬(牙合)异常及侧貌美观.

目的:对比分析儿童青少年骨性Ⅱ类错(牙合)畸形患儿拔牙与非拔牙矫治前后的软组织侧貌变化差异.方法:由近年代向远年代抽取在该院口腔正畸科完成矫治的44例骨性Ⅱ类错(牙合)畸形患儿为研究对象,根据是否拔牙矫治分为拔牙组和非拔牙组,各22例.拔牙组患儿均拔除4颗双尖牙.对矫治前后的X线头颅侧位定位片进行软组织美学指标的测量分析.结果:拔牙组除颏唇沟角(Li-B'-Pos)和面角(NsPg'-FH)矫治前后的变化差异无统计学意义(P＞0.05)外,其余各测量指标均向面突度减小的方向变化,前后差异均有统计学意义(P＜0.05);非拔牙组矫治前后仅下唇倾角(B'Li-FH)和上唇凸距(Ls～REP)的变化差异有统计学意义(P＜0.05).矫治前两组患儿上唇倾角(A'Ls-FH)、Ls-REP、下唇凸距(Li-REP)、Z角和颏沟倾角(Pg'B'-FH)比较,差异均有统计学意义(P＜0.05).矫治后拔牙组的A'Ls-FH、上下唇角(A'Ls-B'Li)、Z角和Pg'B'-FH均大于非拔牙组,差异均有统计学意义(P＜0.05).结论:软组织侧面型较突的骨性Ⅱ类错(牙合)畸形患儿通过拔牙矫治有望获得较大的面型改变,而非拔牙矫治对患儿的侧貌影响较小.

Objective To investigate a simpler method of preparation of customized typodont model in labial and lingual brackets system. Methods Explored a simpler and more precise method of preparation of customized typodont model in labial and lingual brackets system used in the further study of orthodontic mechanics through several test procedures,such as simulating set-up,bonding the labial and lingual brackets,preparing impression with silicon rubber and pouring the typodont models. ResuIts The negative forms suit for preparation of customized typodont model used in comparative research of orthodontic mechanics in labial and lingual brackets system were obtained and the typodont model were made repeatedly. ConcIusion The artificial teeth are very stable in the negative forms and the typodont models can be poured accurately and repeatedly,and be a platform for further comparative research of orthodontic mechanics in labial and lingual brackets system.

目的：探讨矫治乳前牙反牙合同时破除口腔不良习惯的有效方法。方法：将30例3～6岁乳前牙反牙合伴口腔不良习惯患儿随机分为治疗组15例，采用Infant traniner矫治器治疗，对照组15例，采用上颌牙合垫式活动矫治器进行矫治，观察比较两组病例前牙反牙合治疗和口腔不良习惯破除成功率、疗程、复诊次数、椅旁操作时间。结果：两组前牙反牙合矫治成功率差异无统计学意义(＞0.05)。而复诊次数、椅旁操作时间治疗组少于对照组(＜0.001)，对口腔不良习惯的矫治治疗组优于对照组，差异具有统计学意义(＜0.05)。结论：Infant traniner矫治器是矫治乳前牙反牙合同时破除口腔不良习惯的有效方法。