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目的通过对下颌尖牙埋伏阻生进行正畸-外科联合治疗,探讨下颌尖牙埋伏阻生的病因、外科手术暴露部位及正畸牵引导萌方向。方法对2003—2007年就诊于中国医科大学口腔医学院正畸科的5例患者的6颗下颌埋伏阻生尖牙进行正畸-外科联合治疗,先用方丝弓固定矫治器进行间隙扩展,然后根据尖牙位置及与邻牙的关系,采用外科翻瓣导萌术,暴露埋伏尖牙的牙冠,粘接托槽,再选择不同方向和方法对其进行牵引导萌。结果6颗埋伏尖牙均经牵引后排齐,牙髓和牙周情况正常。结论分析下颌尖牙埋伏阻生的病因,选择正确的外科手术暴露部位和正畸牵引导萌方向,可有效地进行矫治。     

上颌尖牙埋伏阻生的外科-正畸联合治疗

目的:探讨尖牙埋伏阻生的外科-正畸联合治疗方法。方法:20例患者28颗上颌埋伏阻生尖牙,先用滑动直丝弓矫治器初步排齐牙列后,再局部间隙扩展,采用外科闭合式助萌技术,暴露埋伏尖牙牙冠,粘贴托槽,再进行正畸牵引导萌。结果:24颗埋伏尖牙均牵引入正常牙列,牙髓、牙周情况正常。有4颗尖牙因横位阻生和根冠成角采用外科拔除。结论:通过外科手术暴露和正畸牵引导萌联合治疗,能有效矫治埋伏阻生尖牙。     

上颌腭侧埋伏阻生尖牙 CBCT 导引下的牵引治疗

目的:探讨锥形束CT(CBCT)三维(3D)重建在上颌腭侧埋伏阻生尖牙牵引治疗中的指导作用。方法:对22例上颌尖牙(共26颗)腭侧埋伏阻生的青少年患者行CBCT检查。CBCT三维重建观察尖牙形态、腭侧埋伏状况,测量分析与邻近组织的位置关系及相邻切牙牙根吸收情况。结果:CBCT能够真实再现颌骨内埋伏的上颌尖牙。埋伏尖牙均近中倾斜,与平面平均成角61.1°±18.1°,近中异位分别为Ⅰ类埋伏尖牙8颗、Ⅱ类5颗、Ⅲ类3颗、Ⅳ类10颗。3颗相邻侧切牙及2颗中切牙因严重牙根吸收而拔除;26颗上颌腭侧埋伏尖牙均成功牵引至平面排入牙弓并建立正常咬合。结论:CBCT能立体再现上颌尖牙腭侧埋伏阻生特征及与邻近牙的关系等,对治疗方案的制定、开窗牵引具有指导作用,可提高疗效。     

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目的比较手术—正畸联合治疗唇侧和腭侧上颌埋伏阻生尖牙的临床疗效。方法对广东省深圳市宝安区人民医院口腔正畸门诊2004—2009年收治的60例埋伏阻生尖牙患者(均为单颗埋伏阻生尖牙患者,共60颗牙),根据全口曲面断层片和X线定位片分为唇侧组和腭侧组各30颗牙,通过手术开窗去除阻力骨、暴露部分牙冠、黏结正畸附件,在固定矫正技术的牵引下将埋伏阻生的尖牙纳入正常牙弓内。对比两组治疗的成功率和治疗所需的时间。结果治疗成功率唇侧组为80.0%,腭侧组为96.7%,两组比较差异有统计学意义(P<0.01)。术后正畸牵引的时间腭侧组为(9.2±3.2)个月,而唇侧组为(15.1±4.1)个月,明显长于腭侧组,两组比较差异亦有统计学意义(P<0.01)。结论经手术开窗正畸牵引,上颌埋伏阻生尖牙的成功率腭侧组大于唇侧组,牵引到位的时间腭侧组也较唇侧组短。     

正畸牵引联合牙槽外科矫治上颌尖牙埋伏阻生的临床观察

目的 观察正畸牵引联合牙槽外科手术矫治上颌尖牙埋伏阻生的临床疗效。方法 对30例上颌尖牙埋伏阻生病例,利用正畸牵引联合牙槽外科手术进行矫治。结果 6例埋伏尖牙,经开拓间隙或减数助萌治疗,3～5个月后自然萌出;24例行牙槽外科开窗术配合正畸牵引,8～12个月后萌出。牙髓活力正常,牙龈形态美观,牙周情况良好。结论 正畸牵引联合牙槽外科手术,可快速有效地矫治上颌埋伏阻生尖牙。     

上颌尖牙埋伏阻生的临床分析

目的对上颌尖牙埋伏阻生的患病特点及治疗结果进行分析,以期为临床治疗上颌尖牙埋伏阻生提供参考数据。方法在北京大学口腔医学院·口腔医院正畸科门诊2001年1月至2005年1月期间诊治的10505例错(牙合)畸形患者中,经CT检查选出上颌尖牙埋伏阻生患者215例(汉族),共有埋伏阻生尖牙248颗。统计上颌尖牙埋伏阻生在正畸患者中所占比例,χ~2检验分别比较患者性别、唇腭侧阻生以及相应治疗情况的差异。结果上颌尖牙埋伏阻生在正畸门诊患者中约占2．05%,女性：男性为1．8∶1,唇侧：腭侧为2．1∶1。“外科手术暴露+正畸牵引”的方式在治疗中占主导地位。“外科手术拔除”的治疗方式在腭侧埋伏阻生尖牙中的应用多于唇侧,差异有统计学意义(P＜0.01)。结论本组患者上颌尖牙埋伏阻生以女性、唇侧多见,临床对唇腭侧尖牙埋伏阻生的治疗存在一定差异。     

上颌埋伏尖牙的外科—正畸治疗

目的　对上颌埋伏尖牙进行外科—正畸治疗。方法　先用方丝弓固定矫治器进行间隙扩展 ,然后根据上颌埋伏尖牙的位置及与邻牙的关系 ,分析其阻生的病因 ,采用外科翻瓣导萌术 ,暴露埋伏尖牙的牙冠 ,粘贴托槽 ,再选择不同的方向和方法对 12例患者的 14颗上颌埋伏尖牙进行正畸牵引导萌。结果　 11颗埋伏尖牙均已萌出后排齐 ,牙髓和牙周情况正常。结论　只有通过从上颌埋伏尖牙的位置关系 ,分析其阻生的病因 ,选择正确的外科手术暴露和正畸牵引导萌的方法 ,才能有效地矫治上颌埋伏尖牙。     

不同年龄组上颌埋伏阻生尖牙正畸牵引的疗效比较

目的:比较成人与青少年上颌埋伏阻生尖牙患者,采用正畸牵引治疗的成功率及其治疗所需时间的差异。方法:选择17例成人和17例青少年患者各21颗上颌埋伏阻生尖牙,2组上颌埋伏阻生尖牙在三维CT片上的位置、三维方向和埋伏阻生程度均相似。对2组正畸牵引治疗的成功率及其治疗所需时间进行比较,分别采用χ2检验和配对t检验进行统计学处理。结果:成人组正畸牵引治疗的成功率为85.71%,青少年组为100%,两者存在显著的差异(P<0.01)。正畸牵引治疗所需时间,成人组长于青少年组,有显著差异(P<0.001)。结论:正畸加开窗牵引上颌埋伏阻生尖牙的成功率,成人组显著低于青少年组,且正畸牵引治疗所需时间也显著长于青少年组。     

上颌埋伏阻生前牙正畸治疗的临床研究

目的：观察上颌埋伏阻生前牙应用固定正畸方法进行矫治的临床疗效,探讨埋伏阻生前牙有效的治疗方法。方法：对49例58颗上颌前牙埋伏阻生病例,应用固定正畸进行矫治,结合牙槽外科开窗术,对埋伏牙进行牵引。其中20颗进行开拓间隙使之自然萌出,38颗进行开窗封闭式牵引导萌矫治。结果：55颗阻生牙矫治后牙髓活力正常、未见埋伏牙及邻牙牙根吸收、牙周组织正常。开窗封闭式牵引导萌有3颗牙治疗失败,总体成功率94.8%。结论：应用固定正畸技术开拓间隙或结合牙槽外科开窗术导萌埋伏阻生牙,可有效保存上颌埋伏阻生前牙。     

预置支点介导下的上颌近远中阻生尖牙的矫治

目的 探讨预置支点在矫治上颌水平阻生尖牙的作用.方法 水平埋伏阻生上颌尖牙5例,均位于邻牙根方.用直丝弓矫治器进行间隙预备,外科开窗暴露埋伏尖牙的牙冠,将预置支点置于牙颈部,进行正畸牵引,曲面断层片观察邻牙牙根吸收情况.结果 水平阻生尖牙以预置支点为转动中心而移动至正常位置,牙髓和牙周情况良好,邻牙牙根无吸收现象.结论 预置支点水平阻生上颌尖牙的转动中心,对正畸临床治疗有指导意义.     

三维CT定位在上颌阻生尖牙拔除中的应用

目的：应用CT对拔除上颌埋伏阻生尖牙进行准确定位，以减少拔除时的盲目性，避免对邻牙及周围组织的损伤。方法：对30例临床上拔除较为困难的埋伏阻生尖牙，拍摄x线全景片和定位片进行分析，并对其中22例较难判断的病例加摄三维CT进行定位，判断埋伏阻生尖牙是否位于唇侧或腭侧，或穿行于唇、腭侧间。结果：30例尖牙埋伏阻生病例，仅8例通过全景片加定位片能较准确地判断其位于唇侧或腭侧，其余22例因移动不明显而难以判断，在通过加摄三维CT后才能准确判断尖牙阻生的位置及与邻牙间的位置关系。结论：三维CT定位准确性高，可避免全景片和定位片因重叠及平面效果而造成的判断错误，减少手术进路的盲目性，缩短手术时间，避免手术中对周围骨组织和邻牙的损伤。     

A review of impacted permanent maxillary cuspids--diagnosis and prevention

As impacted permanent maxillary cuspids occur in 1-2% of the population, the general dentist should know the signs and symptoms of this condition and the interceptive treatment. Features of buccal or palatal cuspid impaction include lack of canine bulges in the buccal sulcus indicating a lingual eruption path and possible impaction; lack of symmetry between the exfoliation and eruption of cuspids that may indicate palatal or lingual impaction; and abnormal mesiodistal location and angulation of the developing maxillary permanent cuspids on radiographs. Diagnosis of impacted cuspid teeth at age 8-10 years can significantly reduce serious ramifications, including surgical exposure and orthodontic alignment as well as root resorption of the lateral incisors. In specific cases, extraction of the primary maxillary cuspids can prevent impaction of the permanent maxillary cuspids and additional sequelae.     

Supernumerary impactions of the mandibular cuspids and bicuspids. Case report

A case involving the presence of supernumerary cuspids and bicuspids is described. The condition was probably an inherited one because of the family history and the bilateral incidence. The supernumerary teeth erupted because of alveolar resorption in which inflammatory factors probably played a role. Radiographic follow-up of the site of supernumerary impacted teeth and alveolar resorption should be undertaken.     

Management of impacted cuspids using 3-D volumetric imaging

Management of impacted cuspids is a complex clinical problem involving proper assessment and interdisciplinary treatment planning. In this paper, we describe the use of 3-D volumetric imaging in the management of impacted cuspids and illustrate this application in case reports of maxillary and mandibular impacted cuspids.     

Transmigration of impacted mandibular cuspids

Transmigration of impacted mandibular cuspid is a rare finding. A cuspid is classified as "transmigrated" when more than half of its length has passed the mid-line. 13 cases of transmigration of impacted mandibular cuspids are presented, 3 of which occurred in pairs, raising the total number of teeth to 16. Radiographs showed positions ranging from a vertical impaction, to a cuspid having crossed the mid-line completely, reaching the first molar area of the opposite side.     

改良舌弓在治疗下颌埋伏牙的作用

目的 探讨改良舌弓在矫治下颌埋伏牙中的作用.方法 5例下颌埋伏牙患者均采用外科-正畸联合治疗,配合戴入改良舌弓,利用改良舌弓位于舌侧不锈钢丝上的附钩,将埋伏牙牙冠朝向正常的位置方向牵引,直到接近其正常的位置.采用直丝弓技术排齐牙列,调整咬合关系.对治疗后牙齿的松动度、牙髓活力等进行观察.结果 5例下颌埋伏牙均被牵引至牙弓的正常位置,牙髓活力测试正常,牙周附着良好,无邻牙和埋伏牙牙根吸收.结论 改良舌弓在矫治下颌埋伏牙时,在矫治力方向设计和支抗控制方面有独特优点和作用.     

The closed eruption technique in cases of impaction of permanent maxillary canines

The impaction of permanent maxillary canines occurs frequently. In recent decades, research has led to 2 methods of treatment: the modified window technique and the closed eruption technique. Although these methods have been described in detail, it is still not clear which method is most effective. In a study involving 73 orthodontic patients with an impacted, palatally displaced permanent maxillary canine, this cuspid was exposed by means of a gingival flap and an orthodontic bracket was immediately fixed on the exposed canine, after which the gingival flap was repositioned using sutures. The patients were clinically and radiographically examined 3 months after the orthodontic treatment. In a control group consisting of 93 orthodontic patients, there were no cases of impacted permanent maxillary cuspids. The overall success rate for the treatment in the study group was 63%. Problems in adjacent teeth were correlated significantly with older age among the patients. There was a significant difference in the number of pockets around the teeth adjacent to the canines in the study group and in the control group.     

Bilateral maxillary dentigerous cysts: a case report

Dentigerous cysts are benign odontogenic cysts that are associated with the crowns of permanent teeth. They are usually single in occurrence and located in the mandible. Multiple cysts are reported in patients with conditions such as mucopolysaccharidosis and basal cell nevus syndrome. We present the radiologic findings of bilateral impacted maxillary cuspids with dentigerous cysts displacing the maxillary sinuses in a nonsyndromic patient, a condition that, to our knowledge, has not been previously reported.     

The maxillary cuspid and missing lateral incisors: esthetics and occlusion.

When maxillary cuspids are moved mesially or if they are absent, it may be safe to assume: 1. There is no apparent change in facial contour. 2. The first premolar can serve as an adequate substitute for the cuspid, both functionally and esthetically. 3. If all spaces are closed, occlusal equilibration will usually be necessary to effect acceptable posterior occlusion. Mesiodistal contouring of the cuspids probably accentuates the problem since it seems to exaggerate any tooth size discrepancy which may exist between maxillary and mandibular teeth. 4. Unilateral space closure displays functional deficiencies more frequently on the side of closure. 5. Varying degrees of shade imbalance between the cuspid and central incisor can be expected, and the degree of contrast can be accurately predicted by using the mandibular cuspid as a guide. This is particularly important when the maxillary canines are impacted or unerupted.     

大型颌骨囊肿伴远端埋伏牙的外科－正畸联合治疗

目的：总结大型颌骨囊肿伴埋伏牙病例进行外科－正畸联合治疗的临床效果。方法：16例大型颌骨囊肿伴远端埋伏牙病例应用开窗减压手术治疗，术中保留累及恒牙，术后配戴囊肿塞治器。术后第1、3、6个月，之后每半年随访，拍摄全景片，观察囊腔减小程度及新骨形成情况，择期正畸牵引或外科辅助正畸牵引埋伏牙复位。结果：16例患者开窗减压术后随访1~5．5年，平均随访3年；囊腔均逐渐减小直至消失，愈合良好，因囊肿而远端异位的牙齿均可自行复位至接近正常位置。替牙完成后配合正畸牵引或外科辅助正畸牵引，正畸疗程平均2年。结论：口腔颌面外科－正畸联合治疗为颌骨囊肿伴埋伏牙的治疗提供了新的方法。