学龄期儿童混合牙列牙齿数目异常分析

［摘要］ 目的 应用曲面断层技术分析学龄期儿童混合牙列牙齿数目异常情况的发生。方法 选取3 432张2013年1月—2017年6月来我院儿童口腔科就诊的5~12岁学龄期儿童拍摄的混合牙列曲面断层片,观察记录先天缺牙、多生牙和牙瘤的发生情况。应用SPSS13.0统计学软件进行χ2检验。结果 牙齿数目异常的患病率为25.52%,男性（27.54%）多于女性（23.24%）,差异具有统计学意义（P<0.05）。先天性缺牙为最常见的牙齿数目异常,患病率为13.43%,女性（6.93%）多于男性（6.5%）, 差异具有统计学意义（P<0.05）。多生牙的患病率为11.74%,男性（7.93%）多于女性（3.81%）, 差异具有统计学意义（P<0.05）。牙瘤的患病率仅为0.35%。结论 混合牙列儿童牙齿数目异常患病率高,先天缺牙最常见。应用曲面断层进行检查,有利于早期发现牙齿数目异常。     

6453名17～21岁青年人恒牙发育异常的调查

目的调查青年人恒牙牙齿形态和数目异常的状况。方法2002至2004年对3所北京高校6453名17～21岁学生进行恒牙数目和形态异常的调查。对不同性别和不同牙位发育异常的患病率进行卡方检验，并对2种牙齿异常伴发的情况进行卡方检验。结果牙齿数目和形态异常的总患病率为16．07％。女性锥形牙或桶状牙、畸形中央尖和先天缺牙的患病率高于男性，差异有统计学意义（P〈0．05）。牙内陷、锥形牙或桶状牙好发于上颌侧切牙，畸形中央尖好发于下颌第二前磨牙，融合牙和先天缺牙好发于下颌切牙，差异均有统计学意义（P〈0．01）。锥形牙或桶状牙与先天缺牙伴发的比率高，差异有统计学意义（P〈0．01）。结论各种牙齿数目和形态异常的患病率、性别差异和好发牙位与以往的研究基本相符。但锥形牙或桶状牙、畸形中央尖的女性患病率均高于男性。     

145例少牙多牙症的回顾性研究

目的 应用曲面体层技术探讨少牙多牙症（CHH）的发生率和临床特征。 方法 收集2019年1月—2021年5月就诊的41 648例儿童口腔科患者的曲面体层片,纳入CHH患者145例,观察记录CHH的发生情况。应用SPSS 24.0软件统计分析所得的数据。 结果 CHH的发生率为0.35%（145/41 648）,男性（102例）多于女性（43例）,性别间差异有统计学意义（P<0.001）。恒牙先天缺失特征：缺失1~2颗为主;最好发下颌侧切牙和下颌第二前磨牙;下颌恒牙先天缺失多于上颌恒牙先天缺失,二者差异有统计学意义（P<0.001）;左侧先天缺失与右侧先天缺失差异无统计学意义（P=0.84）。多生牙特征：数目1~2颗;多见于上颌前牙区;多为圆锥形;垂直倒置生长和垂直正位生长为主。 结论 CHH是一种少见的混合牙齿数目异常,男性多于女性,恒牙先天缺失和多生牙的特征与单独发生的恒牙先天缺失/多生牙的特征相似,建议早期诊断和多学科治疗。     

先天缺牙与牙形态、大小异常相互关系的研究

目的 探讨先天缺牙与牙形态异常及牙大小异常的相互关系。方法 对79例先天缺牙患者的缺牙部位、缺牙数目，余留牙异常的牙体形态进行分析。并按缺牙程度及部位分成4组，测量其牙冠宽度。结果 （1）上颌侧切牙、下颌中切牙为临床最常见牙先天缺失部位，上颌中切牙，上下颌第一磨牙为牙列中最不易先天缺失的牙齿，但上颌中切牙在先天缺牙患者中常呈轻度的锥形牙冠。（2）先天缺牙常伴牙齿形态异常，以上颌侧切牙，下颌尖牙、上颌第二前磨牙，上下颌第二磨牙多见。（3）轻度先天缺牙患者余留牙大小无异常，随着先天缺牙严重程度增加，前牙有逐渐减小趋势而后牙大小较稳定。结论 （1）上颌侧切牙为牙列中最不稳定的牙齿：（2）牙齿形态、大小、数目异常可能是一个连续的变异过程，可能为同一机制的不同表现。     

新疆维、汉大学生恒牙先天缺失情况的调查分析

目的 调查新疆维汉两民族青年人恒牙先天缺失的状况。方法 2008-2009年对新疆高校学生共5150名采取随机、整群抽样的方法 进行恒牙发育异常情况的调查。对总体及维汉两民族先天缺牙情况进行患病率、颌位情况、缺牙数目、好发牙位及同时伴发2种牙齿发育异常的情况进行卡方检验。结果 恒牙先天缺失的总患病率为5.98%,汉族高于维族(P<0.05),维族男性患病率低于女性(P<0.05)。总体及汉族缺牙数目下颌多于上颌(P<0.05),好发牙位为下颌中切牙;总体及维汉均以缺失1颗牙者最多见,且锥形牙与先天缺牙伴发的比率高。结论 恒牙先天缺失的总患病率略低于其他学者的研究,民族间患病率有差异,汉族高于维吾尔族。性别差异、颌位情况、缺牙数目、好发牙位及伴发情况与其他学者的研究基本一致。?     

恒牙先天缺失患者蝶鞍和颅底的头影测量研究

目的 探究不同程度恒牙先天缺失患者蝶鞍与颅底的大小及形态差异。 方法 选取2020—2021年就诊于四川大学华西口腔医院正畸科的322例患者为研究对象,依据先天缺牙数目将患者分为3组：对照组（无恒牙先天缺失,112例）;试验Ⅰ组（先天缺失1~2颗恒牙,104例）;试验Ⅱ组（先天缺失3颗及以上恒牙,106例）。使用Uceph头影测量软件对每位患者头颅侧位片的蝶鞍的长度、深度和直径以及颅底相关线性和角度参数进行测量。对每位患者的蝶鞍形态进行判定。采用SPSS 21.0软件对数据进行统计学分析。 结果 3组的蝶鞍长度、深度、直径以及颅底相关的线性和角度参数差异均无统计学意义（P>0.05）。3组的鞍桥发生率的差异有统计学意义（P=0.013）,试验组高于对照组（P<0.05）,试验Ⅰ组和试验Ⅱ组差异无统计学意义（P>0.05）。 结论 虽然蝶鞍的线性大小及颅底特征在正常人和先天缺牙患者中未见明显差异,但在先天缺牙患者中鞍桥发生率更高,提示该人群的蝶鞍解剖学形态可能异常。     

非综合征型先天缺牙的研究进展

先天缺牙是人类牙列中最常见的发育异常，多为恒牙缺失，乳牙先天性缺失少见。可见为散发病例或家族遗传形式，后者可以是常染色体显性遗传、常染色体隐性遗传或X染色体遗传。先天缺牙根据是否有伴发症状，可分为：①单纯性或非综合征型先天缺牙，即仅有牙齿的先天缺失；②综合征型先天缺牙，即先天缺牙同时伴有其他器官的发育异常。根据缺牙数目可分为个别牙缺失、多数牙缺失和先天性无牙。多数牙缺失是指缺牙数目在6个及6个以上者（不包括第三磨牙）。     

单纯型恒牙先天缺失患者缺牙特点的临床分析

目的了解单纯型恒牙先天缺失患者的缺牙牙位和临床统计学特点。方法收集183例单纯型恒牙先天缺失患者的病史、口腔检查及曲面断层X线片等资料，分类进行统计学分析。结果牙齿缺失数目、性别差异无统计学意义（P〉0.05）；上下颌、左右侧之间牙齿缺失差异无统计学意义（P〉0.05）；最易缺失的牙齿为下颌第二前磨牙，共缺失154颗；多数牙缺失患者磨牙缺失率为25.00％，较个别牙缺失患者磨牙缺失率（3．05％）明显增高，差异有统计学意义（P〈0．05）。结论不同患者恒牙缺失的临床表现不同；单纯型恒牙先天缺失患者中，除第三磨牙外，最易缺失的牙齿是下颌第二前磨牙，其次是下颌切牙、上颌第二前磨牙及上颌侧切牙     

儿童牙齿发育异常Ⅱ.混合牙列期上前牙区额外牙的临床处理

儿童牙齿发育异常讲座上一讲主要是针对牙齿数目的减少即先天缺牙,本讲主要针对牙齿数目增多即额外牙(多生牙)的临床处理.人的一生共经历3个牙列阶段,从最初的乳牙列阶段、其后的混合牙列阶段到最后的恒牙列阶段.乳牙列和恒牙列阶段往往比较稳定,变化很小,而混合牙列阶段伴随乳牙的替换和恒牙的萌出往往变化很大,期间也会出现各种异常,有的属于生理性的、暂时性的,随着牙列的发育会逐渐恢复正常;有的异常是病理性的,需定期观察和早期干预,否则会引起恒牙列严重的错(袷)畸形.早期干预可借助牙齿、牙列和颌骨正在发育的特点,为异常的牙列和牙齿发育提供自行调整的机会,往往起到事半功倍的效果.     

多个恒牙先天缺失的缺牙特点分析

目的比较分析严重恒牙先天缺失病例的缺牙特点,为临床工作提供参考。方法对37例多个恒牙(≥6个)先天缺失的病例按临床表现分为综合征型和单纯型先天缺牙两组,从恒牙先天缺失数目、牙位分布、余留牙畸形及牙齿大小等方面比较分析严重先天缺牙的表型特点。结果综合征型先天缺牙比单纯型先天缺牙在平均缺牙数目、现存牙齿合并畸形上都表现得更为严重(P<0.05);两组严重缺牙患者先天恒牙缺失的牙位分布在上下颌和左右侧之间均无差别(P>0.05),缺失牙位均呈对称分布,但最易缺失的牙位有所不同;严重先天缺牙患者现存恒牙牙冠宽度较正常值偏小(P<0.05)。结论多个恒牙先天缺失包含复杂的临床表现,综合征型与单纯型的严重先天缺牙在口腔缺牙特点上有明显差异,值得临床鉴别参考。     

乌鲁木齐地区青少年恒牙形态及数目异常的分析

目的探讨乌鲁木齐地区青少年先天缺失牙、多生牙、过小牙的发生率及好发部位。方法本文观察和分析了620例患者的全颌曲面体层X线片．均无恒牙拔牙史或牙齿损伤史。结果先天缺失牙（包括第三磨牙）的发生率为45．48％,第三磨牙的缺失发生率为32．58％,缺失牙的好发部位依次为上颌第三磨牙、下颌第三磨牙、下颌侧切牙、下颌中切牙、上颌第二双尖牙等;多生牙发生率为2．58％,好发部位是上颌切牙区。过小牙的发生率为6．30％．其主要为上颌侧切牙。结论牙齿先天缺失在人群中的发生率明显高于多生牙．缺失牙主要发生在功能相对弱的牙位上：缺失牙与过小牙之间存在一定联系．     

Prevalence of dental developmental anomalies: a radiographic study

OBJECTIVES: To determine the prevalence of developmental dental anomalies in patients attending the Dental Faculty of Medical University of Yazd, Iran and the gender differences of these anomalies. DESIGN: A retrospective study based on the panoramic radiographs of 480 patients. Patients referred for panoramic radiographs were clinically examined, a detailed family history of any dental anomalies in their first and second degree relatives was obtained and finally their radiographs were studied in detail for the presence of dental anomalies. RESULTS: 40.8% of the patients had dental anomalies. The more common anomalies were dilaceration (15%), impacted teeth (8.3%) and taurodontism (7.5%) and supernumerary teeth (3.5%). Macrodontia and fusion were detected in a few radiographs (0.2%). 49.1% of male patients had dental anomalies compared to 33.8% of females. Dilaceration, taurodontism and supernumerary teeth were found to be more prevalent in men than women, whereas impacted teeth, microdontia and gemination were more frequent in women. Family history of dental anomalies was positive in 34% of the cases.. Taurodontism, gemination, dens in dente and talon cusp were specifically limited to the patients under 20 year's old, while the prevalence of other anomalies was almost the same in all groups. CONCLUSION: Dilaceration, impaction and taurodontism were relatively common in the studied populaton. A family history of dental anomalies was positive in a third of cases.     

Prevalence of numeric anomalies in the permanent dentition of patients with Down syndrome

The purpose of this study was to evaluate the prevalence of numeric anomalies in the permanent dentition of patients with Down syndrome by means of panoramic radiographs. The sample consisted of panoramic radiographs from 70 subjects. We examiend the radiographs to detect hypodontia as well as supernumerary teeth. Our results confirm the high prevalence of hypodontia among patients with Down syndrome (60%), mostly with mild expression. The teeth most often missing were the upper lateral incisors, usually bilaterally, followed by the lower second premolars and upper second premolars. Supernumerary teeth were seen in 6% of the subjects, and the concomitant occurrence of hypodontia and supernumerary teeth occurred in one patient.     

Labial talon cusp on permanent central incisor: a case report

Talon cusp is a supernumerary crown structure, a developmental disturbance in the shape of teeth that causes various diagnostic, functional and esthetic problems. Some synonyms for talon cusp are dens evaginatus of anterior teeth, interstitial cusp, tuberculated tooth, odontoma of the axial core type, evaginated odontoma, enamel pearl, supernumerary cusp etc. The lingual location on incisors, which frequently affects occlusion, is pathognomonic of the talon cusp. This report describes a rare odontogenic, isolated anomaly rather than an integral part of any disorder, a case of talon shaped cusp projecting from the labial surface of a maxillary permanent central incisor.     

I denti sovrannumerari nel settore latero-posteriore: studio epidemiologico

Objectives

The aim of this study is to investigate the incidence, prevalence, sex difference, topography and morphology of Posterior Supernumerary Teeth (PST) in the Italian Caucasian population.

Materials and methods

Records of 20,398 young patients were evaluated. Only data relating to supernumerary teeth in the posterior region of the jaws were analysed. The diagnosis of hyperdontia was formulated during the clinical and/or X-ray examination. All patients included in the study were in the permanent dentition and were in possession of one panoramic radiograph.

Results

50 posterior supernumerary teeth were found in 37 patients. The prevalence was of 0.18%. The mean age of those 37 patients was 21±3; 25 were males and 12 females (ratio of 2:1). The PST were more frequently found in the maxilla (62%) than in the mandible; over half of them were located in the upper arch (54%); paramolars (63%) were more common than distomolars; supernumerary (60%) were more frequent than supplemental teeth (40%); tuberculate shape was the most frequent (60%).

Conclusions

Epidemiological studies on supernumerary teeth are useful for an early and correct diagnosis. Early detection allows for measures against complications and more successful therapy.     

Dental anomalies and associated factors in 2- to 5-year-old Brazilian children

Background. Dental anomalies in primary teeth may lead to functional and aesthetic disorders, and their recognition contributes to early diagnosis and long-term treatment planning. Objective. This study investigated the prevalence of dental anomalies in primary dentition and associated factors in Brazilian preschoolers. Methods. The study population of this cross-sectional study comprised 1260 2- to 5-year-old children from public nurseries in Canoas, southern Brazil. Dental anomalies were recorded by five trained examiners according to Kreiborg criteria; classification included double teeth, hypodontia, supernumerary, and microdontia. Results. Dental anomalies as a group were found in 2.5% of children, although no significant difference occurred between genders and races. All the anomalies were observed in the anterior region, with no significant differences between the arches. However, supernumerary teeth were significantly more frequent among the non-white racial group (Fisher; P = 0.025) and double teeth on the lower arch (McNemar; P = 0.020). Individual anomaly frequencies were: double teeth, 1.3%; hypodontia, 0.6%; supernumerary, 0.3%; and microdontia, 0.3%. Conclusions. The frequency of primary dentition anomalies as a group was greater than that reported in other populations; the findings of this study provide a clear vision of the distribution of this oral condition and may well contribute to early detection and treatment planning.     

Agenesis of permanent mandibular anterior teeth: a case report

Tooth agenesis is one of the common congenital anomalies seen in humans. Hypodontia is the congenital absence of 1 or a few teeth only, with a prevalence of approximately 2% to 10% in the permanent dentition. The number of patients exhibiting congenitally missing mandibular incisors is low, with a prevalence rate of less than 1% observed. The purpose of this paper was to report a case of congenitally missing permanent mandibular incisors and canines in a 10-year-old girl.     

Tuberculate and odontoma type supernumerary teeth

An 8-and-a-half-year-old girl with supernumerary teeth of tuberculate and odontoma type is described. Treatment of the patient is carried out on conventional lines with a combination of surgical and orthodontic methods. The upper tuberculate type supernumerary teeth were extracted and, after surgical exposure, the upper permanent first incisors were aligned with removable appliances. After secondary dentition was completed, the lower odontoma type supernumerary tooth was removed surgically, and also the maxillary and mandibular first premolars were extracted because of severe crowding, and fixed orthodontic appliances were used to align the permanent dentition. Early diagnosis and treatment of this anomaly is necessary to avoid more serious consequences and to prevent severe orthodontic disturbances.     

Tooth abnormalities and soft tissue alterations in patients with G/BBB syndrome

Objective: The G/BBB syndrome is an X‐linked recessive disorder characterized by eye anomalies, laryngotracheoesophageal cleft, congenital heart disease, genitourinary anomalies and gastrointestinal disorders. Patients may also present cleft lip and palate, high‐arched palate and thin upper lip. This study aimed to investigate the occurrence of tooth abnormalities and soft tissue changes in patients with G/BBB syndrome. Design: Cross‐sectional. Subjects and methods: Twenty‐one patients with G/BBB syndrome were analyzed as to the presence of tooth abnormalities and soft tissue alterations. Main outcome measures: The prevalence of tooth agenesis and supernumerary teeth was compared to patients without morphofunctional alterations, matched for gender and age. Results: All patients had complete cleft lip and palate; 95.23% of patients presented tooth abnormalities, mainly hypoplastic alterations, with predominance of alterations of number, followed by alterations of structure, shape and position. The frequency of tooth agenesis and supernumerary teeth was significantly higher compared with the control group; 11 patients presented incisiform supernumerary teeth in the mandibular anterior region. Ankyloglossia was observed in 11 of 21 patients. Conclusion: The presence of mandibular anterior supernumerary teeth and ankyloglossia should be investigated in the clinical evaluation of patients with suspected diagnosis of the G/BBB syndrome.