恒前牙发育畸形埋伏阻生与治疗

恒牙埋伏阻生是口腔正畸临床常见的错牙合畸形,尤其上前牙最为常见。由于埋伏牙阻生形式复杂,诊断和治疗难度较大,临床常采用颌面外科手术配合正畸治疗。本文报告22例恒牙前牙埋伏阻生与萌出的关系并进行分析讨论。1临床资料1.1一般资料从1999～2002年共收集上颌前牙发育畸形埋     

上颌埋伏多生牙的临床分析附91例报告

超过正常数目而形成的牙齿称为多生牙多生牙可以萌出、埋伏阻生、牙体倒置患者多无自觉症状但可引起各种并发症如错　畸形、邻牙迟萌、牙间隙增宽、牙扭转、邻牙牙根吸收和形成囊肿等因此有必要早期作出诊断予以适当的治疗作者自1996～1998年临床治疗上颌埋伏多生牙91例现...     

60例儿童上切牙区埋伏多生牙的手术体会

６０例儿童上切牙区埋伏多生牙的手术体会首都医科大学附属北京口腔医院口腔儿科李凤霞李新球教授指导埋伏多生牙多因牙列不齐或恒牙迟萌，影响美观被家长重视而就诊。它唯一的治疗方法是手术摘除。由于患者年幼，处于替牙阶段，颌骨内既有多主牙又有未发育完成的恒牙胚，...     

基于锥形束CT的多生牙新分类方法临床意义研究

目的　应用锥形束CT（cone-beam CT,CBCT）对多生牙进行新的临床分类,并分析新分类方法的临床意义。方法　收集2016—2019年首都医科大学附属北京友谊医院口腔科的CBCT影像资料5100例,其中多生牙患者209例,共计多生牙278颗。应用CBCT对多生牙进行新的临床分类,包括萌出型、骨埋伏高位型、骨埋伏低位型、骨埋伏复杂型和牙弓外型,并分析其临床意义。结果　（1）临床资料分析：多生牙发生率为4.1%,其中有1颗多生牙的患者占76.6%,有2颗多生牙的患者占19.1%,有3颗及以上多生牙的患者占4.3%。多生牙好发部位依次为：上颌切牙区、上颌磨牙区、下颌尖牙及前磨牙区、上颌尖牙及前磨牙区、下颌磨牙区。34.9%的多生牙对邻近恒牙产生了继发影响,以萌出错位及阻生为主,主要发生在上颌切牙区。（2）新分类方法的临床意义分析：上颌切牙区多生牙以骨埋伏低位型及萌出型为主,尖牙、前磨牙及磨牙区多生牙以萌出型为主。不同类型多生牙对邻近恒牙产生继发影响的发生率不同或不全相同（χ2 = 26.057,P < 0.001）,提示对邻近恒牙易产生继发影响的多生牙类型依次为：萌出型、骨埋伏复杂型、骨埋伏高位型、牙弓外型、骨埋伏低位型。结论　基于CBCT的多生牙新分类方法简单实用,其中萌出型、骨埋伏复杂型及骨埋伏高位型多生牙更易产生错牙合畸形,建议尽早拔除多生牙、定期随访,必要时正畸治疗。     

基于锥形束CT的多生牙新分类方法临床意义研究

 目的　应用锥形束CT（cone-beam CT，CBCT）对多生牙进行新的临床分类，并分析新分类方法的临床意义。方法　收集2016-2019年首都医科大学附属北京友谊医院口腔科的CBCT影像资料5100例，其中多生牙患者209例，共计多生牙278颗。应用CBCT对多生牙进行新的临床分类，包括萌出型、骨埋伏高位型、骨埋伏低位型、骨埋伏复杂型和牙弓外型，并分析其临床意义。结果　（1）临床资料分析：多生牙发生率为4.1%，其中有1颗多生牙的患者占76.6%，有2颗多生牙的患者占19.1%，有3颗及以上多生牙的患者占4.3%。多生牙好发部位依次为：上颌切牙区、上颌磨牙区、下颌尖牙及前磨牙区、上颌尖牙及前磨牙区、下颌磨牙区。34.9%的多生牙对邻近恒牙产生了继发影响，以萌出错位及阻生为主，主要发生在上颌切牙区。（2）新分类方法的临床意义分析：上颌切牙区多生牙以骨埋伏低位型及萌出型为主，尖牙、前磨牙及磨牙区多生牙以萌出型为主。不同类型多生牙对邻近恒牙产生继发影响的发生率不同或不全相同（χ2 = 26.057，P < 0.001），提示对邻近恒牙易产生继发影响的多生牙类型依次为：萌出型、骨埋伏复杂型、骨埋伏高位型、牙弓外型、骨埋伏低位型。结论　基于CBCT的多生牙新分类方法简单实用，其中萌出型、骨埋伏复杂型及骨埋伏高位型多生牙更易产生错牙合畸形，建议尽早拔除多生牙、定期随访，必要时正畸治疗。     

颅骨锁骨发育不全综合征患者的正畸治疗初探

目的：分析颅骨锁骨发育不全综合征患者的颅面异常表现,并对其进行正畸治疗．探讨该痫的临床诊断、正畸治疗方法。方法：例CCD患者．运川双循序渐进法,即先后运用活动矫治器、固定矫治器,分批次外科于手术窗、拔除多生牙和形态异常牙齿,每次牵引2颗或3颗埋伏的恒牙。结果：2例CCD患者埋伏牙牵引矫治至正常位．面型改善;2例正治疗中。结论：双循序渐进法足矫正CCD患者的牙颌畸形有效方法。     

多颗恒牙迟萌的病因学研究进展

恒牙迟萌是指恒牙萌出时间显著晚于正常萌出期的现象,不仅可引起患儿错(牙合)畸形,还可进一步影响患儿的咀嚼、发音功能与面容美观,严重时将损害患儿正常生长发育及心理健康,给家长带来负担。其发生以个别恒牙较常见,但部分患儿出现多颗恒牙迟萌。多颗恒牙迟萌病因复杂,除局部机械因素外,还可能与环境（如疾病、营养、感染、放射、药物）、遗传等因素具有相关性,本文就以上因素作一综述,以期为多颗恒牙迟萌的病因学研究及临床诊断提供思路。     

乳切牙外伤与恒中切牙发育畸形埋伏阻生的关系

恒牙埋伏阻生是口腔正畸临床常见的错畸形 ,其中以上下尖牙和上切牙为常见。据报道尖牙埋伏阻生发生率为 0 .92 - 3.3%不等 ,恒切牙埋伏阻生的发生率未见报道 ,Ｗｉｌｌｉａｍ等认为较尖牙发生率为少 ,而房伯君等报道恒切牙埋伏阻生多于尖牙。恒牙埋伏阻生的原因至今还不十分明确 ,上中切牙埋伏阻生的原因之一是乳切牙早期外伤乳牙根伤及恒牙胚所致 ,本文报告三例上中切牙埋伏阻生发育畸形的临床病例 ,并从其诊断及处理进行分析讨论。病例一周某 ,男 ,10岁 ,替牙主诉 :2 1|未萌 ,要求矫治现病史 :患者四岁时因摔跤而致乳切牙外伤临床检…     

38例上颌前牙区埋伏多生牙临床分析

儿童发生多生牙,常影响其邻近恒牙的替换、萌出或造成恒牙列的错颌畸形,故及时发现、治疗是十分必要的.现收集、整理自2002年3月至8月期间,儿科门诊中38例共55颗埋伏多生牙的临床资料,就其性别、年龄、发生位置、数目、错(牙合)情况进行分析.探讨如何及时发现埋伏多生牙,准确定位并拔除.     

颅锁骨发育不全综合征的X线特征分析

目的:分析总结43例颅锁骨发育不全综合征病例的临床及X线表现。方法:在国内数据库中对颅锁骨发育不全综合征的病例报道进行检索,并结合本院确诊的4例典型病例,对该病的临床表现、X线特征总结分析。结果:颅锁骨发育不全综合征中男/女约1.6∶1;中位年龄17.6岁;牙、颌面畸形发生率达88%;全身其他部位受累发生率达95.3%。主要的牙、颌面畸形X线特征是部分乳牙滞留,恒牙萌出迟缓或不发育并伴有含牙囊肿。上颌骨及颧骨多发育不足及下颌骨正常发育而形成反面型;其它全身部位受累主要表现在指、跖关节的畸形。结论:颅锁骨发育不全综合征好发年轻男性;牙颌面畸形、锁骨发育不全、"钟形"胸、跗跖关节外移畸形、耻骨联合增宽等是诊断颅锁骨发育不全综合征的主要X线特征,骨盘畸形、掌指及跖趾关节的畸形是诊断该病重要的辅助X线特征。     

颅骨锁骨发育不全综合征：1例家系报告及文献复习

颅骨锁骨发育不全综合征是一种先天性全身骨骼发育不全性疾病,临床罕见,以锁骨发育不良、囟门闭合延迟、方颅、乳牙脱落延迟、恒牙迟萌或阻生、多生牙以及颌骨形态异常为主要临床特征。本文报告1例颅骨锁骨发育不全综合征家系,并结合相关文献,对该病的发病率、发病机制、临床表现、诊断及治疗进行讨论。     

RUNX2 mutations in cleidocranial dysplasia patients

Objective:  Mutations in the RUNX2 gene, a master regulator of bone formation, have been identified in cleidocranial dysplasia (CCD) patients. CCD is a rare autosomal-dominant disease characterized by the delayed closure of cranial sutures, defects in clavicle formation, and supernumerary teeth. The purposes of this study were to identify genetic causes of two CCD nuclear families and to report their clinical phenotypes.
Materials and methods:  We identified two CCD nuclear families and performed mutational analyses to clarify the underlying molecular genetic etiology.
Results:  Mutational analysis revealed a novel nonsense mutation (c.273T>A, p.L93X) in family 1 and a de novo missense one (c.673C>T, p.R225W) in family 2. Individuals with a nonsense mutation showed maxillary hypoplasia, delayed eruption, multiple supernumerary teeth, and normal stature. In contrast, an individual with a de novo missense mutation in the Runt domain showed only one supernumerary tooth and short stature.
Conclusions:  Mutational and phenotypic analyses showed that the severity of mutations on the skeletal system may not necessarily correlate with that of the disruption of tooth development.     

Cleidocranial dysplasia: diagnostic criteria and combined treatment

Cleidocranial dysplasia (CCD) is an uncommon, generalized skeletal disorder characterized by delayed ossification of the skull, aplastic or hypoplastic clavicles, and serious, complex dental abnormalities. There are many difficulties in the early diagnosis of CCD because a majority of the craniofacial abnormalities becomes obvious only during adolescence. In the present case, a hypoplastic midface, a relative prognathia of the mandible, and close approximation of the shoulders in the anterior plane were the conspicuous extraoral findings. Prolonged exfoliation of the primary dentition, unerupted supernumerary teeth, and the irregularly and partially erupted secondary dentition produced occlusional anomalies. The presence of the second permanent molars together with the primary dentition and wide spacing in the lower incisor area were typical dental signs. Gradual extraction of the supernumerary teeth and over-retained primary teeth was the first step of oral surgery. This was followed by a surgical exposure of the unerupted teeth by thinning of the cortical bone. Orthodontic treatment was aimed at parallel growth of the jaws. Removable appliances were used to expand the narrow maxillary and mandibular arches, and a Delaire mask compensated for the lack of sagittal growth of the upper jaw. Temporary functional rehabilitation was solved by partial denture. When the jaws have been fully developed, implant insertions and bridges are the therapeutic measures. The reported case and the literature data support the importance of the early diagnosis and interdisciplinary treatment of CCD.     

Cementum analysis in cleidocranial dysostosis

Objective: Cleidocranial dysostosis (CCD) is a skeletal disorder associated with dental anomalies such as failure or delayed eruption of permanent teeth and multiple impacted supernumerary or permanent teeth. Absence of cellular cementum at the root apex is presumed to be one of the factors for failure or delayed eruption. The aim of this study was to analyze the root cementum of supernumerary(S) and permanent teeth (P) of a CCD patient and to compare the findings with those of normal individuals with special emphasis on delayed eruption. Materials and Methods: Ground sections of 12 extracted teeth (9S + 3P) of a CCD patient and 12 teeth of normal individuals (5S + 7P) were taken for the study. The sections were longitudinal and 50 microm thick. Root characteristics were recorded with the aid of a light microscope. Results: The absence of apical cellular cementum, increased root resorption and increased percentage of the gap type of cemento-enamel (C-E) junctions were significant findings noted both in the supernumerary and permanent teeth of the CCD patient. Conclusion: The presumption of cellular cementum is essential for tooth eruption is not supported by the findings of the present study. Delayed exception could be attributed to various other factors like mechanical obstruction, reduced serum alkaline phosphatase levels etc. Also, the significance of the increased percentage of the gap type of C-E junctions and its role in tooth eruption has to be further evaluated.     

Cleidocranial dysplasia: report of six clinical cases

Cleidocranial dysplasia (CCD) is an autosomal‐dominant disorder that occurs due to mutations in the Cbfa 1 gene, also called Runx 2, located on the short arm of chromosome 6, affecting osteoblast skeletal‐specific bones that have intramembranous ossification. This condition is characterized by hypoplastic clavicles, short stature, and great clinical significance in the stomatognathic complex, with involvement of facial bones, changes in the eruption patterns, including multiple supernumerary and retained teeth. This study reports six subjects of the same family with CCD identified in the Dentistry Clinic of Oral Diagnosis Department, Universidade Paulista, Campus Sorocaba, Sao Paulo State, Brazil. All cases had clinical and radiographic aspects of this important condition, such as short stature, hypertelorism, severe mobility of the shoulders, and supernumerary and retained teeth. Due to the rare incidence and phenotypic manifestations, CCD can be easily misdiagnosed. The oral commitments are one of the main (functional and aesthetic) causes of complaints in these subjects; and a dentist must establish the diagnosis as early as possible, followed by behaviors and practices that can minimize harmful manifestations of the syndrome and improve health associated with oral and multidisciplinary integration offering improvements in quality of life of these subjects.     

Diversity of supernumerary tooth formation in siblings with cleidocranial dysplasia having identical mutation in RUNX2 : possible involvement of non-genetic or epigenetic regulation

INTRODUCTION: Cleidocranial dysplasia (CCD, MIM #119600) is an autosomal-dominant disorder characterized by hypoplasia or aplasia of clavicles, patent fontanelles and short stature. The responsible gene has been identified as RUNX2. CCD is also accompanied by characteristic dental abnormalities, e.g. supernumerary teeth, delayed eruption and impaction of permanent teeth. Intrafamilial variations of skeletal abnormalities are reported but those of dental abnormalities are obscure. To clarify this point, a precise examination of the dental features of CCD siblings having identical mutation was performed. DESIGN: Gene mutational analysis of three Japanese CCD siblings and their father was performed. Skeletal and dental characteristics were examined by the inquiry and radiographs. RESULTS: Three siblings uniformly showed patent fontanelles and short stature. They and their father had a novel missense mutation in the RUNT-domain (P210S) of RUNX2. The siblings were completely discordant for the dental characteristics with the position and number of supernumerary teeth being completely different. The youngest, a 12-year-old boy, had six supernumerary teeth, which appeared symmetrically around the maxillary canines and mandibular premolars. The second, a 15-year-old girl, had four supernumerary teeth which appeared around the mandibular incisors. The oldest, a 17-year-old boy, had 11 supernumerary teeth, which were symmetrically around the mandibular lateral dentition and asymmetrically around the maxillary incisors and premolars. CONCLUSION: The present study suggests the involvement of non-genetic or epigenetic regulation in supernumerary tooth formation in CCD.     

锁骨颅骨发育不全综合征(CCD)1例报告

目的：分析1例锁骨颅骨发育不全综合征的典型病例。为临床正确诊断该类遗传性疾病提供临床依据。方法：对1例锁骨颅骨发育不全综合征患进行临床检查、染色体检查、并对其家族成员进行家系调查。结果：临床确诊锁骨颅骨发育不全综合征，主要临床表现为异常发育的锁骨，囟门的闭合不全，多生牙，身材矮小等一系列骨骼的改变。家系调查被诉怀疑有相关病患发生，染色体检查未见异常。结论：锁骨颅骨发育不全综合征是一种由于常染色体变异所造成的骨骼发育异常。及时正确地诊断该疾病，对于病患的进一步的正畸及修复治疗非常重要。