上颌快速扩弓联合前方牵引治疗骨性Ⅲ类错牙合畸形对上气道影响的锥形束 CT 分析

目的：研究上颌快速扩弓联合前方牵引治疗骨性Ⅲ类错(牙合)畸形对上气道影响的三维变化。方法：选择53例伴上颌骨横向发育不足的骨性Ⅲ类错(牙合)畸形患者。所有患者先采用 Hyrax 矫治器进行上颌快速扩弓,然后前方牵引矫治。平均扩弓16 d,前方牵引平均5个月。分别于扩弓前（T0）、扩弓结束时（T1）及前方牵引结束时（T2）拍摄锥形束 CT 并进行三维重建和测量。结果：扩弓结束时鼻咽段最小截面积、最小截面积处冠状径和鼻咽段容积显著增大（P ＜0．05）;前方牵引矫治后鼻咽段4项指标与扩弓治疗前相比明显增大（P ＜0．05）。结论：上颌骨快速扩弓联合前方牵引可显著增加鼻咽段上气道容积。     

上颌快速扩弓对替牙期骨性Ⅲ类错(牙合)前方牵引治疗的影响

目的:探讨上颌快速扩弓对替牙期骨性Ⅲ类错(牙合)前方牵引治疗的影响.方法:选择8～10岁的骨性Ⅲ类错(牙合)患者24例(男14例,女10例),随机分为扩弓组和非扩弓组,扩弓组在上颌前方牵引治疗前快速扩弓1周,非扩弓组单独使用前方牵引治疗.2组病例治疗前后均拍摄头颅定位侧位片,分别采用传统头影测量方法和Pancherz头颅参照系统对治疗前后的硬组织变化进行分析比较,评价上颌快速扩弓对前方牵引治疗效果的影响.结果:①扩弓组治疗时间19.2±3.2周,非扩弓组22.4±3.6周,两者具有显著性差异;②治疗前后,扩弓组前下面高增加4.10±1.92 mm,非扩弓组增加3.75±2.01 mm,两者具有显著性差异;③治疗前后,扩弓组上颌切牙唇倾度增加2.55°±2.68°,非扩弓组增加4.70°±2.74°,两者具有显著性差异.结论:与单纯使用前方牵引治疗相比,使用上颌快速扩弓联合前方牵引,可以更加快速有效地解除前牙反(牙合),减少上颌切牙的代偿性唇倾,但是会加重下颌骨的后下方旋转.     

快速扩缩弓并前牵引矫治恒牙早期安氏Ⅲ类错殆的疗效

目的研究上颌前方牵引联合快速扩缩弓治疗恒牙早期安氏Ⅲ类错黯的骨性及牙性疗效。方法选取10例恒牙早期安氏Ⅲ类错殆患者,观察6个月作为观察对照期,随后应用前方牵引联合快速扩缩弓矫治6个月为治疗期．应用Pitchfork分析法比较对照期和治疗期在平均功能性殆平面上骨骼及牙齿的位置变化。结果磨牙关系改变了7．2mm（t=6．85．P〈0．05）,包括骨性改变4．4mm、牙性改变2．8mm;骨性改变中上下颌骨贡献率约为1：3,牙性改变中上下磨牙贡献率约为2：3。结论前方牵引联合快速扩缩弓可有效治疗恒牙早期安氏Ⅲ类错胎,可取得较大的牙殆关系改善。     

前方牵引配合Ⅲ类颌间牵引治疗唇腭裂术后Ⅲ类错(牙合)的临床研究

目的 探讨扩弓加前方牵引联合Ⅲ类颌间牵引对唇腭裂术后Ⅲ类错牙合畸形的矫治效果.方法 选择替牙期唇腭裂术后Ⅲ类错牙合畸形患者21例,随机分成2组,A组采用扩弓加前方牵引,B组采用扩弓加前牵联合Ⅲ类颌间牵引的方法进行矫治,治疗前后分别做头影测量并对结果进行统计学分析,比较2组的矫治效果及疗程.结果 扩弓加前牵组与扩弓加前牵联合Ⅲ类颌间牵引组的疗程分别为(29.40±2.88)周和(21.00±2.14)周,前者显著长于后者(P＜0.001).结论 扩弓加前方牵引联合Ⅲ类颌间牵引是治疗唇腭裂术后Ⅲ类错牙合的有效方法,能够明显缩短该类患者的矫治时间.     

恒牙早期Ⅲ类错(牙合)患者前方牵引的骨性和牙性矫治效果分析

目的 应用Pitchfork分析法研究恒牙早期安氏Ⅲ类错(牙合)患者上颌前方牵引联合快速扩弓的骨性和牙性矫治效果,为早期矫治的时机选择提供参考依据.方法 19例恒牙早期安氏Ⅲ类错(牙合)患者,非治疗观察6个月后(观察期),应用前方牵引联合快速扩弓早期矫治6个月(治疗期),随后直接进入固定矫治器治疗.应用Pitchfork分析法对比观察期和治疗期功能性(牙合)平面上骨骼及牙齿的位置改变.结果 在功能性(牙合)平面上早期矫治造成磨牙关系改变了7.9 mm,包括骨性改变4.2 mm、牙性改变3.7 mm;骨性改变中上颌骨贡献了0.7 mm,下颌骨贡献3.6 mm,牙性改变中上磨牙贡献了1.5 mm,下磨牙贡献2.2 mm.结论 恒牙早期阶段开始前方牵引联合快速扩弓的早期矫治Ⅲ类错(牙合)可取得较大的牙(牙合)关系改善,但对上颌骨的作用有限.     

两种不同扩弓方法结合上颌前方牵引的初步研究

目的探索反复快速扩弓回缩结合上颌前方牵引的可行性和方法,对比上颌单次快速扩弓和反复快速扩弓回缩结合前方牵引治疗的效果。方法选择20例上颌后缩患者,每组10例。A组：上颌单次快速扩弓加前方牵引,B组：上颌反复快速扩弓回缩加前方牵引。对治疗前及前方牵引6个月后的头颅侧位片进行头影测量分析。结果两组病例扩弓并前方牵引6个月后上颌显著前移和逆时针旋转,下颌向后下方旋转,上切牙唇倾、下切牙舌倾。两组间对比：反复扩弓回缩组前方牵引后上颌前移量（A点3．56mm）显著大于单次扩弓组（A点2．12mm）。结论使用上颌反复扩弓回缩结合前方牵引的方法治疗上颌后缩患者是可行的,其对前移上颌的效果优于单次扩弓结合前方牵引治疗。     

快速扩弓联合前方牵引治疗早期骨性Ⅲ类错的临床研究

目的运用支架式快速扩弓器进行前方牵引,评价其软硬组织发生的变化。方法 15例替牙期患儿,年龄9～11岁,先进行快速扩弓1～2周,然后行前方牵引,治疗前、后摄头颅定位侧位片并进行头影测量分析。结果快速扩弓后进行前牵引治疗前、后结果差异有显著性,上颌骨及上牙弓均前移,软组织侧貌明显改善。结论在替牙期前方牵引联合快速扩弓治疗早期骨性Ⅲ类错可获得较多的骨骼变化,侧貌改善明显。     

腭部不同类型快速扩弓配合前方牵引的应用进展

上颌快速扩弓配合前方牵引面具是早期治疗上颌骨发育不足的骨性安氏Ⅲ类错牙合常见方法之一.传统方法常用牙和黏膜支持式装置治疗替牙期及恒牙早期的骨性Ⅲ类患者,随着种植支抗的发展,种植钉被广泛应用于正畸治疗中,展示出稳定的骨性支抗效果.本文将对腭部不同类型快速扩弓配合前方牵引技术作一简要综述,为临床治疗提供参考.     

11例10～14岁骨性Ⅲ类错牙合患者的疗效观察

目的观察联合应用前方牵引和上颌快速扩弓治疗10～14岁骨性安氏Ⅲ类错牙合患者的临床效果.方法以11例10～14岁骨性Ⅲ类错牙合患者为观察组,32例替牙早期骨性Ⅲ类错牙合患者为对照组.两组均采用联合应用前方牵引和上颌快速扩弓装置治疗,平均治疗时间6个月.治疗前后均拍摄头影侧位片,并采用一种新的头颅参照系统,对结果进行分析比较,评价治疗效果.结果两组患者均发生上颌骨前移,下颌骨向下后旋转,向前生长受限.观察组前牙覆盖增加5.3mm,骨性变化占51%,牙性变化占49%;其中,9例患者前牙达到正常覆牙合、覆盖关系,磨牙中性关系,2例患者前牙达到浅覆牙合、浅覆盖关系,后牙中性偏近中关系.结论联合应用前方牵引和上颌快速扩弓治疗10～14岁轻中度骨性反牙合患者有较好疗效,可减轻畸形程度,避免手术治疗,最大程度地改善患者的软硬组织关系.     

上颌快速扩弓对替牙期骨性Ⅲ类错前方牵引治疗的影响

目的:探讨上颌快速扩弓对替牙期骨性Ⅲ类错前方牵引治疗的影响。方法:选择8～10岁的骨性Ⅲ类错患者24例(男14例,女10例),随机分为扩弓组和非扩弓组,扩弓组在上颌前方牵引治疗前快速扩弓1周,非扩弓组单独使用前方牵引治疗。2组病例治疗前后均拍摄头颅定位侧位片,分别采用传统头影测量方法和Pancherz头颅参照系统对治疗前后的硬组织变化进行分析比较,评价上颌快速扩弓对前方牵引治疗效果的影响。结果:①扩弓组治疗时间19.2±3.2周,非扩弓组22.4±3.6周,两者具有显著性差异;②治疗前后,扩弓组前下面高增加4.10±1.92mm,非扩弓组增加3.75±2.01mm,两者具有显著性差异;③治疗前后,扩弓组上颌切牙唇倾度增加2.55°±2.68°,非扩弓组增加4.70°±2.74°,两者具有显著性差异。结论:与单纯使用前方牵引治疗相比,使用上颌快速扩弓联合前方牵引,可以更加快速有效地解除前牙反,减少上颌切牙的代偿性唇倾,但是会加重下颌骨的后下方旋转。     

Three-dimensional prospective evaluation of tooth-borne and bone-borne surgically assisted rapid maxillary expansion

AimTo three-dimensionally (3D) assess the long-term effects of tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME).Subjects and methodsThis prospective cohort study comprised 45 consecutive skeletally mature non-syndromic patients with transverse maxillary hypoplasia. In 28 patients, a tooth-borne distractor (Hyrax) was used for expansion, whereas in the remaining 17 a bone-borne distractor (transpalatal distractor, TPD) was used. Cone beam computed tomography (CBCT) scans were performed before treatment (T0) and 22 months later, after fixed appliance treatment (T1). 3D models were constructed from CBCT data and superimposed using voxel-based matching. Distance maps between the superimposed models were computed to evaluate the amount of skeletal changes.ResultsThe distance maps of the superimposed models showed positive distances on the right and left posterior alveolar segments of the maxilla indicating lateral expansion. The anterior maxillary region showed negative distances or posterior displacement and remodelling of the anterior alveolar region. There was no statistically significant difference between TPD and Hyrax for the three alveolar segments (p values ranged 0.63–0.81).ConclusionBone-borne and tooth-borne SARME were found to produce comparable results at the end of fixed appliance treatment regarding skeletal changes.     

Photoelastic effects of maxillary protraction on the craniofacial complex

The conventional treatment of anterior crossbites has been the application of orthopedic force to the mandible to redirect its growth. However, in the patient with an underdeveloped maxilla, this treatment alone is not sufficient. Therefore, the purpose of this investigation was to study the orthopedic effects of maxillary protraction appliances in the treatment of anterior crossbites. A three-dimensional anatomic model of a human skull was fabricated with birefringent materials for photoelastic analysis. Three maxillary protraction appliances that utilized different anchorage units were used. The protraction forces placed on these appliances were parallel to the occlusal plane, a downward vector 20 degrees to the occlusal plane, and a combination of these two vectors. The resulting stress patterns were observed. The effects of the forces produced by the three appliances were transmitted to the maxilla and distant craniofacial structures. Both a parallel traction and a 20 degrees downward pull to the occlusal plane caused a constriction of the anterior portion of the maxilla. The parallel traction caused a counterclockwise (opening) rotation of the molar tooth and palatal plane. A 20 degrees downward force to the occlusal plane decreased this effect.     

Rapid maxillary expansion--tooth tissue-borne versus tooth-borne expanders: a computed tomography evaluation of dentoskeletal effects

This study evaluated rapid maxillary expansion (RME) dentoskeletal effects by means of computed tomography (CT), comparing tooth tissue-borne and tooth-borne expanders. The sample comprised eight girls aged 11 to 14 years presenting Class I or II malocclusions with posterior unilateral or bilateral crossbite that were randomly divided into two treatment groups, palatal acrylic (Haas-type) and hygienic (Hyrax) expanders. All appliances were activated up to the full seven mm capacity of the expansion screw. The patients were subjected to a spiral CT scan before expansion and after a three-month retention period when the expander was removed. One-millimeter-thick axial sections were scanned parallel to the palatal plane, comprising the dentoalveolar area and the base of the maxilla up to the inferior third of the nasal cavity. Multiplanar reconstruction was used to measure maxillary transverse dimensions and posterior teeth inclination by means of a computerized method. The results showed that RME produced a significant increase in all measured transverse linear dimensions, decreasing in magnitude from dental arch to basal bone. The transverse increase at the level of the nasal floor corresponded to one-third of the amount of screw activation. Tooth-borne (Hyrax) and tooth tissue-borne (Haas-type) expanders tended to produce similar orthopedic effects. In both methods, RME led to buccal movement of the maxillary posterior teeth, by tipping and bodily translation. The second premolars displayed more buccal tipping than the appliance-supporting teeth. The tooth tissue-borne expander produced a greater change in the axial inclination of appliance-supporting teeth, especially first premolars, compared with the tooth-borne expander.     

不同快速扩弓装置对牙根吸收影响的系统评价

目的 评估不同类型的快速扩弓装置对牙根吸收的影响.方法 电子检索文献数据库,包括5个英文库及2个中文库,合格文献类型为随机对照试验、临床对照试验、队列研究以及病例-对照研究.由3名研究者进行数据提取,随机对照试验及非随机试验由不同量表进行偏倚风险评估.结果 初筛的400篇研究中,共有7篇符合标准纳入本系统评价.其中3篇...     

2种前方牵引装置前牵引唇腭裂患者上颌骨的三维有限元分析

目的:建立含微钛板支抗和牙支持式前牵引装置的唇腭裂颅上颌复合体三维有限元模型,探讨其前牵引生物力学效应.方法:选取1例恒牙早期唇腭裂男性志愿者,进行锥形束CT(cone beam CT,CBCT)扫描,构建模型,模拟加力,分析位移变化及应力分布.结果:建立了含微钛板支抗和牙支持式前牵引装置的单、双侧唇腭裂颅上颌复合体三维有限元模型.前牵引时,上牙弓内缩;微钛板支抗模型上颌中上部位移量大于牙支持式模型,后者上颌前部及上尖牙位移量大于前者.微钛板支抗模型应力集中于上颌骨中上部,牙支持式模型的应力集中在上颌尖牙点,且前者应力值及分布范围均大于后者.双侧唇腭裂模型上前牙牙槽嵴处位移小于单侧唇腭裂模型,后者患侧位移和应力分布范围均大于健侧.结论:本研究构建的模型生物力学仿真性好,为唇腭裂上颌骨前牵引治疗的生物力学研究提供了良好的实验载体.微钛板支抗上颌骨前牵引以骨性作用为主,牙支持式上颌骨前牵引以牙性作用为主,前者更有利于效果稳定和侧貌改善.     

Mandibular widening by intraoral distraction osteogenesis

Transverse mandibular deficiency with crowding of the mandibular anterior teeth is frequently present in patients with Class I and II malocclusions. The hallmarks of treatment by compensating orthodontics, functional appliances or orthopaedic devices are instability, compromised periodontium and compromised facial aesthetics. A new surgical technique has been developed to widen the mandible. The method is based upon gradual osteodistraction following vertical interdental symphyseal osteotomy. Ten patients with transverse mandibular deficiency and significant dental crowding were treated by symphyseal distraction and subsequent non-extraction decompensating orthodontic treatment. Either an intraoral tooth-borne Hyrax appliance or a new custom-made bone-borne osteodistractor was used to gradually widen the mandible. The surgical procedures were accomplished under local anaesthesia and intravenous sedation in an ambulatory surgical setting using an individualized distraction protocol. The appliances were activated 7 days after symphyseal osteotomies, once each day at a rate of 1 mm per day and stabilized for 30–60 days after distraction. After the segments were distracted, non-extraction orthodontic alignment of the mandibular anterior teeth was accomplished. The symphyseal distraction gaps were bridged by new bony regenerate. Distraction osteogenesis provided an efficient surgical alternative to orthognathic surgery for widening the mandible and treatment of transverse mandibular deficiency without extraction of teeth.     

骨支持式手术辅助上颌骨快速扩弓位移分布的三维有限元分析

目的:研究骨支持式手术辅助上颌骨快速扩弓中颅面部各解剖部位的位移情况.方法:建立骨支持式手术辅助上颌骨快速扩弓系统的三维有限元模型,手术方式采用腭中缝联合侧方皮质骨切开术,模型上选取24个解剖结构,加载横向7mm扩弓量,比较分析颅面部各个解剖部位在矢状向、横向、垂直向的位移分布情况.结果:矢状向观,上颌骨各解剖结构都有明显的向前位移的趋势,而面上部解剖结构都有向后移位的趋势.横向正面观,颅上颌复合体呈金字塔样打开,鼻腔底部明显扩大约4.5mm;殆面观,支抗牙的牙根位移(第一前磨牙为2.92mm,第一磨牙为3.26mm)小于相应区域颊侧牙槽骨的位移(第一前磨牙区3.76mm,第一磨牙区3.93mm),腭板前部比后部扩开更大.垂直向观,上颌骨正中区的腭板有向下位移的趋势,颅面部其余解剖部位都向上移动.结论:骨支持式手术辅助上颌骨快速扩弓时,上颌骨在三维方向上有不同程度的移动、旋转和侧方倾斜,利用这些变化,可以辅助矫正轻度颅颌面畸形.骨支持式扩弓器将扩弓力直接传导到骨骼上,因此可以很好地避免牙支持式扩弓器扩弓时引起的牙及其周围支持组织损伤等严重并发症.     

The Hybrid Hyrax Distalizer,a new all-in-one appliance for rapid palatal expansion,early class III treatment and upper molar distalization

Abstract

Growing class III patients with maxillary deficiency may be treated with a maxillary protraction facemask. Because the force generated by this appliance is applied to the teeth, the inevitable mesial migration of the dentition can result in anterior crowding, incisor proclination and a possible need for subsequent extraction therapy. The Hybrid Hyrax appliance, anchored on mini-implants in the anterior palate, can be used to overcome these side-effects during the facemask therapy. In some class III cases, there is also a need for subsequent distalization after the orthopaedic treatment. In this paper, clinical application of the Hybrid Hyrax Distalizer is described, facilitating both orthopaedic advancement of the maxilla and simultaneous orthodontic distalization of the maxillary molars.     

Evaluation of miniscrew-supported rapid maxillary expansion in adolescents: A prospective randomized clinical trial

Objectives:To evaluate and compare the dental and skeletal changes with conventional and miniscrew-supported maxillary expansion appliances in adolescents.Materials and Methods:Forty patients were divided into two groups, with one group receiving a tooth-borne expander and the other group receiving an expander supported by four miniscrews (bone-borne). Multiplanar coronal and axial slices obtained from cone-beam computed tomography images were used to measure the changes in transverse skeletal widths, buccal bone thickness, tooth inclination, and root length. Paired t-tests and independent-sample t-tests were used to compare the two expansion methods.Results:Bone-borne expansion increased the maxillary suture opening more than 2.5 times than tooth-borne expansion both anteriorly and posteriorly. Between the maxillary first premolars, sutural expansion accounted for 28% and 70% of the total transverse width increase in the tooth-borne and bone-borne expander groups, respectively. Similarly, 26% and 68% of the total expansion was of skeletal nature in the tooth-borne and bone-borne expander groups between the maxillary first molars. The pattern of expansion was variable, with most of the patients in both groups demonstrating a triangular-shaped sutural opening that was wider anteriorly. Subjects in the conventional group experienced significantly more buccal bone reduction and greater buccal inclination of the teeth. No significant differences were observed for root length measurements between the two groups.Conclusion:Use of bone-borne expansion in the adolescent population increased the extent of skeletal changes in the range of 1.5 to 2.8 times that of tooth-borne expansion and did not result in any dental side effects.     

Osseointegrated titanium implants for maxillofacial protraction in monkeys

Titanium implants were placed surgically into the maxillary, zygomatic, frontal, and occipital bones of four pigtail monkeys. After a 4-month healing period, the implants were exposed and abutments were placed. Extraoral traction appliances were then attached to the abutments. The cranial implants were used to support the framework of the traction appliance; those in the facial bones were used to attach springs that delivered a protraction force. The application of force varied among animals. In animal A, the force was applied to the maxilla. In animal B, the force was applied to the zygomatic bones. Animals C and D had force applied to both the maxillary and zygomatic bones. A tensile force of 600 gm per side was maintained until approximately 8 mm of maxillary anterior displacement had occurred. This amount of movement required 12 weeks of force application in animals A and B, and 18 weeks in animals C and D. Cephalometric and dry skull analyses showed that the amount of skeletal protraction was significant. The findings also demonstrated that it was possible to control the direction of maxillary protraction. The facial implants remained immobile throughout the experiment.