尖牙的迁徙

阻生尖牙穿越颌骨中线迁徙至对侧颌骨是一少见的现象,通常将其定义为“迁徙”。本文就尖牙迁徙的患病率及分类、临床特点、病因学、萌出力学和治疗方法作一综述。     

尖牙的迁徙

阻生尖牙穿越颌骨中线迁徙至对侧颌骨是一少见的现象，通常将其定义为迁徙”。本文就尖牙迁徙的患病率及分类、临床特点、病因学、萌出力学和治疗方法作一综述。     

泸州地区青少年尖牙阻生的X线分析

目的：通过X线全景片分析泸州地区青少年的尖牙阻生情况。方法：选取2011年1月。2012年12月在泸州医学院附属口腔医院接受x线检查的1800例12—14岁青少年的X线全景片,统计分析阻生尖牙所占比例以及患者的性别、尖牙阻生部位和阻生类型的差异。结果：尖牙阻生在所有患者中所占比例为3．72％（67／1800）,男性：女性为1：1．79;上颌尖牙阻生占3．33％（60／1800）,下颌尖牙阻生占0．33％（6／1800）,上下颌尖牙同时阻生1例;近中向阻生在阻生尖牙中占92％（69／75）,迁徙尖牙占0．22％（4／1800）。结论：本组患者尖牙阻生以女性、单侧上颌尖牙阻生多见,且以近中向阻生为主。     

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。     

迁徙还是漂移:5例下颌尖牙病案分析

为提高对下颌尖牙迁徙性阻生的临床认识,本文报告5例患者6颗下颌尖牙迁徙性阻生的CBCT影像学资料,对其影像学表现进行分析讨论。5例患者中男1例,女4例,年龄13～24岁。CBCT影像学资料显示多数尖牙呈水平状横卧于下颌骨体内,其中1例患者双侧下颌尖牙迁徙性阻生,其余4例患者单侧下颌尖牙迁徙性阻生。CBCT的应用对于全面了解下颌尖牙迁徙性阻生的发病情况、临床表现和鉴别诊断具有重要的临床价值。     

异位尖牙自体移植的5年临床效果研究

目的 对正畸牵引困难的异位尖牙,应用牙种植外科技术结合正畸治疗进行尖牙移植,评价其软组织美学及长期效果.方法 对9位患者10例正畸牵引困难的异位尖牙行移植术.其中,男性4名,女性5名;年龄13岁～37岁,平均19.8岁.尖牙埋伏阻生8例,异位萌出2例;上颌7例,下颌3例.术前正畸,调整受植牙区近远中间隙.应用牙种植技术预备受植床,骨引导再生技术修复骨缺损及稳定移植牙.术后正畸排齐牙列.定期随访.临床检查评价牙龈软组织美学、牙及牙周组织状态.影像学检查评价牙根、根周膜及硬骨板状况.结果 所有病例随访2年～9年,平均5.1年.牙龈软组织美学评分13.33±0.87.牙周袋深度均小于3 mm.牙髓电活力测试正常4例.影像学检杳显示,根周膜间隙正常及硬骨板连续7例,根周间隙模糊2例,牙根替代性吸收1例.结论 本研究提示,结合牙种植外科技术和正畸治疗的异位尖牙移植,为正畸牵引困难尖牙提供了美学效果和长期效果良好的治疗选择.

Abstract：

Objective To evaluate the esthetics and outcome of the ectopically positioned canines treated with autotransplantation and orthodontics. Methods Ten ectopic canines in 9 consecutive patients (4 female, 5 male; mean age 19. 8 years, range 13～37 years) were included.Eight of them were deeply impacted and two canines were ectopically erupted (7 maxillary and 3 mandibular canines). The space of recipient site was created orthodontically before surgery. The recipient socket was prepared with dental implant surgery system. After transplantation, bone defect was grafted with guided bone regeneration (GBR) technique. Postoperative orthodontic treatment was carried out. Patients were followed up every 6 months. The pink esthetic score was evaluated.Periodontal pocket depth was measured. Pulpal vitality was assessed. Periapical radiograph was taken to evaluate root resorption, periodontal space and lamina dura. Results The average follow-up period was 5. 1 years (range 2～9 years). The pink esthetic score was 13. 33±0. 87. All pocket depth was less than 3 mm. Radiographic examination showed uninterrupted periodontal space and lamina dura in 7 cases, unclear periodontal space in 2 cases and replacement resorption in 1 case. Conclusions Autotransplantation of the ectopically positioned canines with the combination of dental implant surgical techniques and orthodontics could be suggested as an esthetic and predictable treatment modality.     

上颌阻生尖牙与正畸矫治

上凳恒尖牙的埋伏阻生较常见，且影响美观及功能。本文较详细地介绍了近年来国内外文献、资料对上颌阻生尖牙的综合处理。讨论了上颌阻生恒尖牙的发生原因，阻生尖牙的定位方法，阻生尖牙矫治方案的确定，阻生尖牙的外科协助处置以及正畸桥治阻生尖牙的各种方法。     

上颌尖牙埋伏阻生移植术的临床观察

上颌尖牙埋伏阻生临床较多见 ,笔者自 1992年以来将这种牙拔除后移植到正常位置 ,取得了较好的效果 ,现报告如下 :1　临床资料本组共 18例 ,男 8例 ,女 10例 ,年龄 17～ 2 4岁 ,牙根均已形成。其中 13埋伏阻生 6例 ,2 3埋伏阻生 12例。有乳尖牙滞留者 14例 ,无乳尖牙滞留者 4例。2　治疗方法局麻下在龈唇沟或腭粘膜作切口 ,剥离粘膜瓣 ,去骨 ,拔除埋伏牙。将埋伏牙用盐水纱布包裹待用。测量第一前磨牙与侧切牙的距离 ,如距离较窄 ,片切少许移植牙的近远中面。制备牙槽窝 :如有乳尖牙存在 ,拔除后用圆凿 ,扩大牙槽窝并向上加深 ;如无乳尖牙 ,…     

异位尖牙自体移植的5年临床效果研究

Objective To evaluate the esthetics and outcome of the ectopically positioned canines treated with autotransplantation and orthodontics. Methods Ten ectopic canines in 9 consecutive patients (4 female, 5 male; mean age 19. 8 years, range 13～37 years) were included.Eight of them were deeply impacted and two canines were ectopically erupted (7 maxillary and 3 mandibular canines). The space of recipient site was created orthodontically before surgery. The recipient socket was prepared with dental implant surgery system. After transplantation, bone defect was grafted with guided bone regeneration (GBR) technique. Postoperative orthodontic treatment was carried out. Patients were followed up every 6 months. The pink esthetic score was evaluated.Periodontal pocket depth was measured. Pulpal vitality was assessed. Periapical radiograph was taken to evaluate root resorption, periodontal space and lamina dura. Results The average follow-up period was 5. 1 years (range 2～9 years). The pink esthetic score was 13. 33±0. 87. All pocket depth was less than 3 mm. Radiographic examination showed uninterrupted periodontal space and lamina dura in 7 cases, unclear periodontal space in 2 cases and replacement resorption in 1 case. Conclusions Autotransplantation of the ectopically positioned canines with the combination of dental implant surgical techniques and orthodontics could be suggested as an esthetic and predictable treatment modality.     

影像学预测上颌尖牙阻生的研究进展

上颌阻生尖牙是临床上常见的难题.早期对可能发生阻生的上颌尖牙进行干预,常常可以减轻其阻生的严重程度,甚至可以使尖牙正常萌出.临床上常通过影像学方法对上颌尖牙阻生进行早期预测.其中影像学检查不仅包括传统的全口曲面体层片等二维影像,也包括近年来发展比较迅速的锥形束CT三维影像.本文通过回顾以往研究来总结目前影像学预测上颌尖...     

Forced-eruption time for palatally impacted canines treated with and without ostectomy-decortication technique

Objectives:To compare forced-eruption times for palatally impacted canines treated with and without the ostectomy-decortication technique and to assess the influence of palatally impacted canine pretreatment position and angle on forced-eruption time.Materials and Methods:The sample was composed of 118 patient-subjects with 151 palatally impacted canines treated with the ostectomy-decortication technique (n = 72) and without (n = 79). The orthopantomogram radiographs (OPGs) were analyzed for palatally impacted canine angle and horizontal and vertical position. Recovery time was measured from the start of forced eruption until the canine was within ±1 mm of final dental arch position.Results:The time of forced canine eruption with ostectomy-decortication technique was significantly shorter than without (6.6 vs 21.0 months). Pretreatment canine position significantly increased forced-eruption time in the ostectomy-decortication group but not in the control sample.Conclusions:Forced-eruption time of palatally impacted canines using the ostectomy-decortication technique was 3.2 times more rapid than without. Forced-eruption time increased significantly as a function of pretreatment palatally impacted canine position severity in the ostectomy-decortication group but not in the control.     

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目的：探讨阻生上颌尖牙合适的临床处理策略,为其合理治疗提供依据。方法回顾2000-2012年期间在大连市口腔医院正畸科接受治疗的35例阻生上颌尖牙病例的临床资料,总结分析尖牙阻生状况及相应的治疗措施和疗效。临床处理方法包括拔除、助萌和导萌。结果拔除2例;只做正畸治疗的助萌法16例,留出足够间隙后等待阻生尖牙自行萌出,观察时间5～24个月,均取得良好治疗效果,矫治后阻生尖牙牙龈形态及牙根状况良好;正畸附加外科手术牵引的导萌法17例,除1例21岁男性患者外,其余16例均牵引到位,但矫治后部分阻生尖牙牙龈形态不如助萌法矫治后。结论当阻生上颌尖牙牙体严重畸形、根弯曲短小及高位近远中向横位阻生时考虑拔除;阻生上颌尖牙近远中向错位不严重,扩弓或减数拔牙即可为阻生尖牙留出足够萌出间隙,判断其能自然萌出时首选助萌法;阻生上颌尖牙近远中向错位严重或阻生尖牙已伤及邻牙牙根、仅用正畸治疗无法去除阻生尖牙萌出障碍时采用导萌法,导萌术后的牵引需注意控制牵引方向及大小,要避免伤及邻牙牙根,尽量使阻生牙从附着龈萌出,有利于形成良好的牙龈形态。     

上颌中切牙与尖牙同时阻生的临床特征分析

目的分析上颌中切牙与同侧尖牙同时阻生病例的临床特征。方法选择上颌中切牙与同侧尖牙同时阻生病例21例,分析上颌中切牙阻生类型与尖牙阻生情况,测量阻生侧及对侧侧切牙发育或萌出异常情况。结果与中切牙阻生同时发生的尖牙76.2%为唇侧阻生,其中完全易位与不完全易位占唇侧阻生尖牙的68.8%,尖牙唇侧阻生病例中侧切牙根远中倾斜和伴牙冠近中倾斜者占87.5%,尖牙唇侧或腭侧阻生病例中,出现锥形或过小等畸形侧切牙的比例分别为31.25%和40.00%。上颌中切牙与尖牙不同阻生类型患者,前牙反牙合比例都超过40%,且多为牙型反牙合。结论与中切牙阻生同时发生的尖牙阻生多为唇侧阻生,与中切牙阻生类型无关,与侧切牙根远中倾斜高度相关,尖牙完全易位与过小或锥形等畸形侧切牙有关。     

上颌埋伏尖牙CT影像分型系统的建立和分析

目的 利用螺旋CT三维重建技术建立适合上颌埋伏尖牙的影像学分型系统。方法 选择102例上颌埋伏尖牙患者为研究对象,共121颗上颌埋伏尖牙。所有患者均接受标准的螺旋CT扫描,数据均导入MIMICS 10.01软件采用表面遮盖成像法进行三维重建。通过对121颗上颌埋伏尖牙的三维空间位置进行分析建立上颌埋伏尖牙的影像学分型系统。结果 本研究建立了一个上颌埋伏尖牙的三维CT影像学数据库。研究结果显示在X轴方向上,最常见的分型是牙尖近中伴根尖正常。在Y轴方向上,样本中所有埋伏尖牙只存在3种分型即根尖均处于高位,牙尖分别处于高、中、低位。在Z轴方向上,最常见的分型是牙尖和根尖均处于唇侧,约占总数的三分之一。结论 本研究利用螺旋CT建立了一个适合上颌埋伏尖牙的三维影像学分型系统,具有一定的临床诊断价值。     

单侧上颌尖牙阻生对牙颌三维结构的影响

目的: 采用锥形束CT（CBCT）研究单侧尖牙阻生病例牙颌的三维结构特征,评估发生上颌尖牙阻生的相关风险因素,为正畸临床早期干预提供依据。方法: 选取30例单侧上颌尖牙阻生患者的CBCT,利用Romexis软件进行三维重建,测量、比较两侧牙颌三维结构特征指标,采用SPSS17.0软件包进行配对t检验和相关数据的回归分析。结果: 阻生侧尖牙和侧切牙倾斜度明显增大,尖牙牙冠更向近中、侧切牙向远中倾斜（P<0.001）;阻生侧尖牙体积更大、侧切牙体积更小（P<0.05）,当尖牙体积增大或侧切牙体积减小时,上颌尖牙的阻生概率增加;阻生侧牙弓弧形长度更短,牙弓宽度在尖牙区和前磨牙区更短（P<0.001）,而宽度在磨牙区无显著差异（P>0.05）,两侧牙弓长度在尖牙区、前磨牙区和磨牙区无显著差异（P>0.05）。结论: 上颌尖牙阻生伴随或导致同侧牙及牙槽骨三维方向发育异常,上颌尖牙阻生的严重程度与周围牙颌结构异常密切相关,提示上颌尖牙阻生可以早期预判、诊断,且可以实施有效的早期干预。     

External invasive resorption: Case report of a rapidly progressive process in an impacted maxillary canine during orthodontic treatment

External invasive resorption (EIR) is a type of external resorption that can involve the coronal, middle and apical parts of the root in its advanced stages and results in progressive loss of tooth structure. Common potential predisposing factors for EIR are orthodontic treatment and trauma. The EIR progression rate has not been described previously. This case report describes rapidly progressive EIR in an impacted maxillary canine after surgical exposure and application of directional orthodontic traction over 8 months. The article discusses the etiologies of EIR, the possible reasons for EIR and its rapid progression in the presented case and proposes a new theory of the connection between EIR and tooth impaction.     

Transmigration of permanent mandibular canines. Case report

Transmigration is the migration of a tooth across the midline of the jaw. This phenomenon is found only in relation to the permanent mandibular canines. Two cases are reported. In both, the cause of this deviation was an odontome found in the site normally occupied by the mandibular canine. The literature on transmigration is reviewed.     

Case of unilateral transposition of a maxillary lateral incisor and canine treated without extraction

In this article, we report the successful treatment of a patient, aged 11 years 5 months, who presented for treatment with a chief complaint of lack of eruption of his maxillary left canine. Panoramic radiography and computed tomography revealed complete transposition of the maxillary left lateral incisor and canine. The patient was treated with surgical exposure and traction of the impacted canine to an appropriate location, followed by nonextractive treatment with full resolution of the transposition of the lateral incisor and canine. The diagnosis, planning, appliance design and treatment sequences are described. Alternative treatments, including their advantages and disadvantages, are also discussed.