The use of mini-implants in en masse retraction for the treatment of bimaxillary dentoalveolar protrusion

This case report describes the treatment of a 22-year-old girl who had incompetent lips with severe bimaxillary dentoalveolar protrusion. The treatment of choice for such patients is usually extraction of four first premolars and retraction of the anterior teeth. To maintain the extraction space, maximum anchorage is required. Mini-implants were used to provide maximum anchorage for obtaining a good facial profile.     

΢��ֲ��֧�����γ��˹���˫�ǰͻӦ���о�

目的    研究微种植体支抗在成人骨性双颌前突矫治中的临床应用。方法    选择2006年3月至2009年9月河源市人民医院口腔科就诊的骨性双颌前突错牙合患者13例，其中男4例，女9例，年龄18 ~ 45岁。患者均采用滑动直丝弓技术进行双尖牙减数矫治，在上颌第二双尖牙和第一磨牙之间的颊侧分别植入微种植体，在更换至稳定弓丝后利用种植体整体内收前牙，平均治疗时间为23个月。治疗前后均拍头颅侧位片，并进行头影测量分析。结果    患者侧貌得到明显改善，磨牙未发生明显移动，治疗后U1-SN、U1-NA、L1-NB、 Ls-E、Li-E Pg'B'-FH、G-Sn-Pg'明显减小，与治疗前比较差异均具有统计学意义（P < 0.05），而SNA、SNB 和FH-Ns-Pg'矫治前后差异无统计学意义（P > 0.05）。结论    上颌植入微种植体支抗能够有效矫治成人骨性双颌前突错牙合 ，并达到磨牙强支抗效果。     

自攻型微钛钉种植体增强磨牙支抗的临床应用研究

目的　介绍自攻型微钛钉种植体用于正畸支抗的临床经验 ,评价该型种植体作为强支抗的有效性。方法　在 6 7例采用自攻型微钛钉种植体作为支抗的临床病例中 ,选择 5例II类骨型、上牙弓前突或双牙弓前突患者 ,矫治设计上颌均为减数双侧第一前磨牙 ,支抗设计为磨牙强支抗。内收前牙阶段的治疗应用自攻型微钛钉支抗种植体 ,种植体植入上颌第一恒磨牙与第二前磨牙颊侧根尖部之间的牙槽间隔 ,以每侧 15 0～ 2 0 0g力滑动法内收前牙。比较内收前后头颅X线侧位片 ,测量前牙内收情况和磨牙支抗的变化。结果　 5例牙弓突度均得到明显改善 ,切牙切缘平均内收 6 4mm ,支抗磨牙平均前移 0 3mm ,均获得磨牙强支抗的效果。治疗过程中种植体均保持了稳定 ,种植体周围软组织健康。结论　自攻微型钛钉种植体能作为稳定的骨性正畸支抗 ,代替口外力的使用 ,起到磨牙强支抗的效能。该型种植体具有操作简单灵活 ,可即刻加力 ,不依赖患者合作的优点     

���Ԣ�����ΰ����������Ʋ���

提要：骨性Ⅱ类错牙合畸形的掩饰性治疗是正畸矫治的难点之一。正畸掩饰性治疗通过不同的拔牙模式，移动上下牙齿，来掩饰上下颌骨间的Ⅱ类不调关系，改善软组织侧貌。其常见的拔牙模式包括：双颌拔除[4    4]　　、[4    4]　　或[4    4]　　、[5    5]　　，单颌拔除[4    4]　　，或再补充拔除　[1]或　[1]。应根据颌骨畸形程度和生长型、磨牙远中关系程度、牙列拥挤度等畸形特征，具体分析，严格选择。矫治过程中，应结合不同拔牙方案的矫治特点，注意支抗、前牙转矩等的控制，以获得相对理想的治疗效果。     

Bimaxillary dentoalveolar protrusion: traits and orthodontic correction

A group of 48 ethnically diverse patients with bimaxillary protrusion was used to study the pretreatment cephalometric traits of this malocclusion and the effect of orthodontic correction. All patients were treated with four premolar extractions and retraction of the anterior teeth. Pre- and posttreatment lateral cephalograms were evaluated using a series of 18 linear and angular measurements, and the effect of orthodontic correction was determined using paired t-tests. Cephalometric standards were developed for bimaxillary protrusions, which clarify the overall presentation of this malocclusion for clinicians. Patients with bimaxillary protrusion demonstrated increased incisor proclination and protrusion, a vertical facial pattern, increased procumbency of the lips, a decreased nasolabial angle, and thin and elongated upper and lower anterior alveoli. This study also showed that the extraction of four premolars can be extremely successful in reducing the dental and soft tissue procumbency seen in patients with bimaxillary protrusion, thus providing a stronger evidence-based rationale for this treatment modality.     

双颌前突用无托槽隐形矫治器矫治1例

患者为安氏I类、均角的牙列轻度拥挤伴双颌软组织前突,拔除4个第一前磨牙,应用国产无托槽隐形矫治器矫治,解除牙列拥挤,内收上下前牙,建立前牙正常覆覆盖及尖牙、磨牙中性咬合关系,前突侧貌改善明显。     

Autotransplantation of a premolar tooth in a case of dental bimaxillary protrusion with multiple missing permanent premolars

This paper describes orthodontic treatment combined with autotransplantation of a premolar tooth in a girl aged 8 years 10 months with dental bimaxillary protrusion associated with congenitally missing bilateral lower second premolars and the upper left first and second premolars. We transplanted the right second premolar to the socket of the left second deciduous molar tooth prior to comprehensive orthodontic treatment, and the other socket spaces were closed orthodontically appliances. Good occlusion and facial esthetics were achieved, and these results have been maintained for 3 years after completion of the active treatment.     

A case report of adult skeletal mesio-occlusion

The patient was a 22-year-old female with a class III malocclusion characterized by maxillary constriction, dental crowding and mandibular protrusion. The treatment goals which were related to the chief complaints included correction of negative overjet, negative overbite, and dental alignment. Since the pre-existing crowding created some severe problems and prevented adequate posterior repositioning of the mandible and anterior teeth, extraction of the four first premolars were recommended to correct the overjet. This treatment resulted in greater posterior repositioning. The treatment was divided into three stages: 1) extraction of first premolar teeth, alignment, space closure and an increase in the overjet and overbite, 2) arch alignment and detailing of the occlusion with a full fixed appliance, and 3) retainers. At the end of the treatment, the patient had an acceptable dental alignment with a class I molar relationship and an improvement in facial appearance.     

微种植支抗矫治成人骨性Ⅱ类突面型患者的矢状向疗效观察

目的 使用微种植支抗矫治成人骨性Ⅱ类突面型,观察矫治前后矢状向牙齿突度和唇突度变化.方法 选取36例治疗结束的成人骨性Ⅱ类突面型患者,所有患者均是拔除4颗第一前磨牙使用自攻型微种植体作为支抗内收前牙.对治疗前、后头颅侧位片进行测量分析.结果 36例患者的切牙、软组织等测量指标发生显著性变化,上切牙内收(5.98±3.8...     

A case of tooth autotransplantation after long-term cryopreservation using a programmed freezer with a magnetic field

This case report describes the treatment of a skeletal Class III malocclusion with autotransplantation of a cryopreserved tooth. To gain an esthetic facial profile and good occlusion, extraction of bimaxillary premolars and surgical therapy were chosen. The patient had chronic apical periodontitis on the lower left first molar. Although she did not feel any pain in that region, the tooth was considered to have a poor prognosis. Therefore, we cryopreserved the extracted premolars to prepare for autotransplantation in the lower first molar area because the tooth would probably need to be removed in the future. The teeth were frozen by a programmed freezer with a magnetic field (CAS freezer) that was developed for tissue cryopreservation and were cryopreserved in −150°C deep freezer. After 1.5 years of presurgical orthodontic treatment, bilateral sagittal split ramus osteotomy was performed for mandible setback. Improvement of the facial profile and the occlusion were achieved in the retention phase. Six years after the initial visit, the patient had pain on the lower left first molar, and discharge of pus was observed, so we extracted the lower left first molar and autotransplanted the cryopreserved premolar. Three years later, healthy periodontium was observed at the autotransplanted tooth. This case report suggests that long-term cryopreservation of teeth by a CAS freezer is useful for later autotransplantation, and this can be a viable technique to replace missing teeth.     

Unusual extraction treatment of Class I bialveolar protrusion using microimplant anchorage

This case report describes the treatment of a 16-year-old girl who had severe bialveolar protrusion. Patients with bialveolar protrusion are commonly treated with four first premolar extractions and retraction of the anterior teeth. Unfortunately in this patient, the mandibular left second molar had to be extracted because of extensive caries. To create sufficient space for retraction of the anterior teeth, the mandibular left posterior teeth were retracted with the mandibular posterior microimplant (1.2 mm in diameter, 6 mm long) placed into the retromolar area followed by en masse retraction of the mandibular anterior teeth. Microimplants can provide anchorage for obtaining a good facial profile even without premolar extraction in the case of bialveolar protrusion with the absence of the second molar.     

SPEED矫治器治疗双牙弓前突牙[牙合]结构变化的研究

目的采用 SPEED 托槽对双牙弓前突患者通过一步滑动法关闭拔牙间隙,研究治疗前后牙雅结构的变化。方法选择双牙弓前突病例16例,男2人,女14人,平均年龄16.7岁。拔除四个第一双尖牙。治疗前后拍摄头颅定位侧位片并进行测量。结果治疗后上下切牙切缘分别后移10.63mm、7.87mm,根尖分别后移4.78mm、4.47mm,差异有统计学意义;上下磨牙分别前移1.39mm、1.99mm,差异有统计学意义。U1/SN、U1/PP分别减小15.03°和14.39°,L1/MP 减小6.05°,差异有统计学意义。结论SPEED 矫治器能有效矫治双牙弓前突患者,上下前牙回收明显,而磨牙前移较少。在没有借助口外力及其它附加装置的条件下,仍可以进行很好的支抗控制,但上前牙的转矩控制可能不足。     

Dentoalveolar and skeletal changes associated with the pendulum appliance.

The purpose of the study was to examine the dentoalveolar and skeletal effects of the pendulum appliance in Class II patients at varying stages of dental development and with varying facial patterns (high, neutral, and low mandibular plane angles). Specifically, the amount and nature of the "distalization" of the maxillary first molars and the reciprocal effects on the anchoring maxillary first premolars and incisors were studied, as were skeletal changes in the sagittal and vertical dimensions of the face. Pretreatment and posttreatment cephalometric radiographs obtained from 13 practitioners were used to document the treatment of 101 patients (45 boys and 56 girls). The average maxillary first molar distalization was 5.7 mm, with a distal tipping of 10.6 degrees. The anchoring anterior teeth moved mesially, as indicated by the 1.8-mm anterior movement of the upper first premolars, with a mesial tipping of 1.5 degrees. The maxillary first molars intruded 0.7 mm, and the first premolars extruded 1.0 mm. Lower anterior facial height increased 2.2 mm; there was no significant difference in lower anterior facial height increase between patients of high, neutral, or low mandibular plane angles. In patients with erupted maxillary second molars, there was a slightly greater increase in lower anterior face height and in the mandibular plane angle and a slightly greater decrease in overbite in comparison to patients with unerupted second molars. Similar findings were observed in patients with second premolar anchorage versus those with second deciduous molar anchorage. The results of this study suggest that the pendulum appliance is effective in moving maxillary molars posteriorly during orthodontic treatment. For maximum maxillary first molar distalization with minimal increase in lower anterior facial height, this appliance is used most effectively in patients with deciduous maxillary second molars for anchorage and unerupted permanent maxillary second molars, although significant bite opening was not a concern in any patient in this study.     

Treatment of Class II protrusion with severe crowding using indirect miniscrew anchorage

This report describes the nonsurgical treatment of a patient with skeletal Class II protrusion and severe crowding. A 20-year-old woman presented with the chief complaint of lip protrusion and crowding. To correct the Class II relationship, severe crowding, and lip protrusion, distal movement of the maxillary first molars using indirect miniscrew anchorage and nickel-titanium coil springs, along with extraction of the first premolars and maxillary second molars, was planned. After the distal molar movement phase was complete, the maxillary first molars had moved 8.0 mm to the distal, and the first premolars, which were splinted to the miniscrews, had moved 0.5 mm to the mesial. The results show that the distal molar movement mechanics were efficient and stable. After treatment, all of the patient's chief complaints were relieved and an esthetic facial profile was obtained.     

青少年双颌前突患者拔牙矫治前后侧面部软组织改变的研究

目的 研究青少年双颌前突患者拔牙矫治前后侧面部软组织的改变。方法 对34名青少年双颌前突患者拔牙矫治前后的18项侧面部软组织指标进行对比,通过配对t检验来分析治疗后侧面部软组织的改变。结果 18项软组织指标中5项角度指标的改变在男性组与女性组的改变均有统计学意义,13项线距测量指标中的上唇厚度、下唇厚度、鼻凸度均增大,而鼻底厚度在男性组与女性组改变不同。结论 青少年双颌前突患者拔牙矫治前后面部凸度减小,男性与女性上唇、下唇的变化不同,患者的鼻、唇、颏关系得到改善,软组织侧貌发生明显改变。?     

双颌前突畸形正畸治疗后颅面硬组织变化的研究

目的研究正畸治疗对双领前突患者硬组织矢状及垂直向的影响。方法对24例广东籍双领前突患者在拔除4个第一双尖牙后,采用标准方丝弓矫治技术进行矫治,并对矫治前后硬组织侧貌的变化进行分析。结果 ①上下领骨间关系无明显变化,上下前牙突度和倾斜度明显减小。②前后面高明显增加,但前后面高间的比值及反映下领平面倾斜度的MP-FH无明显变化。③上下磨牙高度随前后面高的增加而明显增加。④上前牙高度明显增加,下前牙高度明显减小。结论双领前突畸形正畸治疗中垂直向及矢状向支抗可得到较好控制。     

3种减数方案矫治双颌前突高角病例的临床研究

目的比较3种减数方案矫治双颌前突高角病例的临床疗效。方法选取14～25岁安氏Ⅰ类高角的双颌前突患者共30例为研究对象,分为3组,每组10例。Ⅰ组拔除4颗第一前磨牙;Ⅱ组拔除上颌2颗第一前磨牙及下颌2颗第一磨牙;Ⅲ组拔除上颌2颗第一前磨牙及下颌2颗第一磨牙,并在上颌2颗第一磨牙的近中分别种植2枚微型种植体。使用直丝弓矫治技术进行矫治。对3组患者治疗前后的头颅侧位X线片进行头影测量分析,并对结果进行统计学分析。结果1）硬组织方面,矫治后Ⅱ、Ⅲ组的前面高、后面高与前面高之比、前下面高、眶耳平面与下颌平面交角、前颅底平面与下颌平面交角、ODI值的变化与Ⅰ组相比,其差异均有统计学意义（P<0.01）。2）软组织、牙齿及牙槽方面,矫治后Ⅱ、Ⅲ组的颏厚度、下唇凸度、颏唇沟深度、LL-E、L1-NB、L1/NB、U1/L1、L7-MP的变化与Ⅰ组相比,其差异均有统计学意义（P<0.01）。3）所有患者均得到完善的正畸治疗,矫治后后牙咬合关系良好,前牙覆覆盖正常,软组织侧貌协调。结论1） 拔除下颌第一磨牙可使下颌平面角变小,前面高及前下面高降低,下颌切牙后缩明显,相应的软组织改变较好;2）上颌附加使用微型种植体支抗更有利于上颌切牙内收和继发的软组织改善;3）矫治高角双颌前突患者时,拔除第一磨牙并使用微型种植体支抗可有效改善患者的面部外型轮廓。     

����˫�ǰͻ�������������

双颌前突畸形在正畸临床上比较常见,尤其是骨性双颌前突,严重影响患者的侧貌外形和美观。临床矫治欲达到理想的疗效也比较困难。本文结合临床这一常见的错畸形,首先介绍了双颌前突的一般情况,叙述了临床上对双颌前突的分类,常用两种分类方法,旨在更好地指导矫治计划的制定。本文就临床上的诊断问题进行了讨论。根据头影测量资料,一是可依据美容线(E线),评估双颌前突的程度,简单易行;二是可依据面平面,即鼻根点至硬组织颏前点的连线,此线与上下唇唇突点的距离可用来评估双颌前突的程度。牙性双颌前突是正畸矫治的适应证,骨性双颌前突一般首选正畸、正颌联合治疗,手术方法一般选择颌骨前部根尖下截骨后退术。术前术后均需进行常规的正畸治疗。手术治疗后,颌骨及牙齿可瞬间后移7.0mm左右,而软组织可后移5.0～6.0mm,美观效果明显改善,可达到满意的疗效,无其他不良反应出现。     

Severe anterior open bite malocclusion with multiple odontoma treated by C-lingual retractor and horseshoe mechanics

A fixed lever arm appliance called C-lingual retractor was placed on the lingual aspects of the maxillary anterior teeth in a 16-year-old male patient with a Class II anterior open bite malocclusion. The treatment plan consisted of extracting both upper first premolars and retracting the upper six anterior teeth. A multiple odontoma between the lower left lateral incisor and canine was surgically removed before orthodontic treatment, and a horseshoe appliance was used in the lower dentition for intermaxillary anchorage during the bone-healing period. The transpalatal arches soldered to the upper first and second molar bands were used as an intra-arch anchor unit for upper-space closure. Class II elastics were used buccally between the upper six anterior teeth and the lower horseshoe appliance. We took 13 months to treat the open bite malocclusion. There was a decrease in lip fullness as the upper anterior teeth were retracted, which contributed to a decrease in facial convexity. The treatment result was maintained six months after debonding. Details of the new appliance, clinical procedures, and treatment changes are presented.     

Combined orthodontic and surgical treatment of severe mandibular laterognathie with bimaxillary protrusion: case report

This article summarizes the treatment progress for a patient with a severe dolichofacial pattern with a convex profile, severe lip incompetency, and concomitant mouth breathing. Her maxillary occlusal plane had a cant and the maxillary and mandibular midlines were shifted 2 and 4 mm to the left side, respectively. The treatment plan summary was as follows: (1) maxillary rapid expansion for the elimination of maxillary constriction; (2) extraction of maxillary right first molar; (3) extraction of mandibular first premolars; (4) preoperative orthodontic treatment to correct dental protrusions; (5) surgical repositioning of the maxilla and mandible; and (6) postoperative orthodontic treatment and retention. Orthodontic treatment lasted a total of 28 months, with a good intercuspation and significantly improved facial esthetics at the end of treatment. The 1-year postretention lateral cephalometric measurements did not indicate any significant relapse. Dental protrusion and crowding in both jaws were eliminated. Facial and dental asymmetry was resolved and the profile was improved. The cant of the occlusal plane and the lips were corrected. Evaluation of pre- and posttreatment profiles revealed a decrease in convexity. Dentally, Class I canine and Class III molar relationships were present at the end of the treatment. Maxillary and mandibular incisors were uprighted, improving the interincisal angle and the bite relationship.