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1.
The talon cusp is a relatively rare dental developmental anomaly characterised by cusp-like projections, usually observed on the lingual surface of the affected tooth. Normal enamel covers the cusp and fuses with the lingual aspect of the tooth. The cusp may or may not contain an extension of the pulp. This occurs in either maxillary or mandibular anterior teeth in both the primary and permanent dentition. This study reports the unusual case of a 47-year-old female with a taloned tooth on the right maxillary central incisor possessing both lingual and labial talons, with an x-shaped appearance when viewed occlusally.  相似文献   

2.
This study investigated the prevalence and distribution of anomalies of permanent dentition in the current Japanese population by examining an unbiased sample. We conducted a survey of dental anomalies by mass dental screening at eight high schools in 2012. Participants were all students with permanent dentition. Dental anomalies were classified as hypodontia, supernumerary teeth, peg-shaped teeth, fused teeth, and talon cusps. Students with one or more dental anomalies on oral examination were given a differential diagnosis by three specialists. The final sample comprised 9584 participants (5062 boys, 4522 girls). Hypodontia was present in 372 students (3.88 %) with no significant sex difference (191 boys, 181 girls). Frequent sites were the right or left mandibular second premolar, right or left maxillary second premolar, and right or left maxillary lateral incisor. Supernumerary teeth were observed in three boys (0.06 %) and one girl (0.02 %). Peg-shaped teeth were observed in 74 students (0.77 %; 27 boys, 47 girls), differing significantly between sexes; they were most prevalent among maxillary lateral incisors. Of affected students, 18 students (0.19 %) also had hypodontia (3 boys, 15 girls). Fused teeth were present in two boys (0.04 %) and three girls (0.07 %) (gemination in one boy and fusion in the remaining four students). Sites were limited to maxillary and mandibular central and lateral incisors. Talon cusps were observed in two boys (0.04 %) and four girls (0.09 %). The present survey of a large unbiased sample can be considered to reflect the prevalence and distribution of anomalies of permanent dentition in the current Japanese population.  相似文献   

3.
AIM: The purpose of this report is to present two cases of totally impacted maxillary deciduous molars, considered a rarity in dental practice. BACKGROUND: Primary tooth impaction is quite rare during the development of primary dentition. Various factors contribute to the impaction of a deciduous tooth, including anklyosis, congenitally missing permanent teeth, defects in the periodontal membrane, trauma, injury of the periodontal ligament, precocious eruption of the first permanent molar, defective eruptive force, or a combination of these factors. REPORTS: Case #1: An 18-year-old male presented with a complaint of spontaneous repetitious pain in the maxillary right premolar region. The maxillary right second premolar was clinically absent. Panoramic and periapical radiographs revealed an impacted second premolar close to the inferior wall of the maxillary sinus and an impacted deciduous molar deeply embedded in bone within the maxillary sinus. Case #2: A 14-year-old girl presented with a complaint of crowding of the maxillary teeth. The maxillary right second premolar and the maxillary permanent canines were clinically absent. A panoramic radiograph revealed an impacted maxillary right second premolar and an impacted deciduous molar embedded within bone close to the inferior wall of the maxillary sinus. SUMMARY: The total impactation of deciduous teeth is a rare condition, and few cases have been reported in the literature. The condition generally affects the mandibular second deciduous molar and the maxillary first deciduous least often. In this paper, two cases of totally impacted maxillary deciduous molars are reported.  相似文献   

4.
Talon cusp is a developmental dental anomaly thought to arise as a result of evagination on the surface of a tooth crown before calcification has occurred. The etiology remains unknown. The incidence is 0.04-10%. Any tooth may have a talon cusp but most of the cases involve maxillary lateral incisors, with some instances of bilateral involvement. The anomaly has been reported to be rare in the mandible. This article reports four cases of talon cusp. The first and the second cases describe bilateral involvement of talon cusp on palatal surfaces of maxillary primary centrals; in the third case talon tubercle occurs on palatal surfaces of both maxillary permanent lateral incisors and the maxillary left central incisor and in the last case a talon cusp in the lingual surface of mandibular permanent lateral incisor.  相似文献   

5.
abstract Mean times of emergence of the permanent teeth, except the third molars, and mean times of onset of specific dental stages were studied cross-sectionally in nearly 8,000 Danish children. In both sexes, a tendency for grouped emergence was observed, the teeth within a group showing similar mean times of emergence. The following groups were distinguishable: (1) the first molar in each jaw and the mandibular central incisor, (2) the maxillary central and mandibular lateral incisor, (3) the mandibular canine and the first premolar in each jaw, and (4) the maxillary canine and the second premolar in each jaw. The sex difference in emergence timing ranged from 2–11 months. In Denmark, the first visit to the Child Dental Services usually takes place when the children enter school in the year they attain the age of 7 years. The present findings indicate that, in order to include the initial phase of permanent tooth emergence, organized dental care should be introduced at least 1 year earlier.  相似文献   

6.
abstract Mean times of emergence of the permanent teeth, except the third molars, and mean times of onset of specific dental stages were studied cross-sectionally in nearly 8,000 Danish children. In both sexes, a tendency for grouped emergence was observed, the teeth within a group showing similar mean times of emergence. The following groups were distinguishable: (1) the first molar in each jaw and the mandibular central incisor, (2) the maxillary central and mandibular lateral incisor, (3) the mandibular canine and the first premolar in each jaw, and (4) the maxillary canine and the second premolar in each jaw. The sex difference in emergence timing ranged from 2–11 months. In Denmark, the first visit to the Child Dental Services usually takes place when the children enter school in the year they attain the age of 7 years. The present findings indicate that, in order to include the initial phase of permanent tooth emergence, organized dental care should be introduced at least 1 year earlier.  相似文献   

7.
Abstract  – The talon cusp, or dens evaginatus of anterior teeth, is a relatively rare dental developmental anomaly characterized by the presence of an accessory cusp-like structure projecting from the cingulum area or cemento–enamel junction. This occurs in either maxillary or mandibular anterior teeth in both the primary and permanent dentition. One of the main problems caused by accessory cusps are occlusal interferences. The anomalous cusp even can generate occlusal trauma and reversible acute apical periodontitis of the opposing tooth. This article reports a case of talon cusp affecting the permanent maxillary left lateral incisor that caused clinical problems related to occlusal trauma and apical periodontitis caused by a premature contact. The treatment of the occlusal interference produced by the taloned tooth is described.  相似文献   

8.
Talon cusp is a rare dental anomaly, especially when it occurs on mandibular teeth. A case of talon cusp on a permanent mandibular central incisor is described and illustrated. This case was associated with periodontitis, but was otherwise symptom free.  相似文献   

9.
The talon cusp, or dens evaginatus of anterior teeth, is a relatively rare dental developmental anomaly characterized by the presence of an accessory cusplike structure projecting from the cingulum area or cementoenamel junction. This occurs in either maxillary or mandibular anterior teeth in both the primary and permanent dentition. This article reports five cases of talon cusp, two of them bilateral, affecting permanent maxillary central and lateral incisors and canines that caused clinical problems related to caries or occlusal interferences.  相似文献   

10.
Talon cusp is an uncommon anomaly, whose etiology may be disturbances in the morphodifferentiation stage. Dens in dente is also a rare anomaly that is challenging in clinic as it may cause pulp necrosis or periapical lesions due to the communication with the oral cavity. This article reports multiple talon cusps on permanent maxillary and mandibular incisors and molars in 3 siblings. A 9-year-old boy presented with structures like nodules, shaped as cylindrical cones with a sharp point or a raindrop with deep developmental fissures on the palatal aspect of the maxillary central incisors, lingual aspect of the mandibular central incisors and labial aspect of both mandibular first molars. The buccal surface of the maxillary right central incisor was also affected. Some of them exhibited dens in dente. His 15-year-old sister had prominent talon cusps on the palatal surface of maxillary central incisors and buccal surface of the mandibular first molars and mandibular left second molar. His 7-year-old brother had only one trace talon on the maxillary left central incisor. No syndrome was identified in the patients. In conclusion, genetic inheritance may be a causative factor in talon cusp.  相似文献   

11.
AimThe purpose of this study was to investigate the prevalence of congenitally missing permanent teeth in Japanese children residing in south-west area of Kanto district in recent years.MethodsPanoramic radiographs taken for dental treatment between 1990 and 2007 were used to evaluate the congenitally missing permanent teeth excluding the third molar. The participants of this study consisted of 2,125 children aged between 7 and 20 years.ResultsThe congenitally missing teeth were observed in 251 participants (11.8%). The majority of the participants (114) presented with only one tooth missing, and there was a general tendency that the number of participants gradually decreased as the number of missing teeth increased. A total of 539 teeth were congenitally missing, and mandibular second premolar was the most frequently missing tooth (153 teeth), followed by mandibular lateral incisor (86 teeth), maxillary second premolar (71 teeth), maxillary lateral incisor (61 teeth). Only one missing tooth (114 participants) was found most frequently in mandibular lateral incisor (30 participants), followed by mandibular second premolar (28 participants). There was a tendency that congenitally missing teeth occurred symmetrically; especially most of the participants who had two missing teeth (80 in 88 participants) were symmetrically missing.ConclusionThe prevalence of congenitally missing permanent teeth in this study was 11.8% and it was comparable to those reported in previous studies of Japanese population evaluated using panoramic radiographs.  相似文献   

12.
The term talon cusp refers to a relatively rare dental anomaly in which an accessory cusplike structure projects from the cingulum area or cement-enamel junction. The condition can occur in either maxillary or mandibular anterior teeth in both the primary and permanent dentitions. This article reports 2 cases of talon cusp affecting consanguineous first cousins: a case of bilateral talon cusps on the permanent maxillary lateral incisors of a 16-year-old girl, and a case of talon cusp on the maxillary permanent lateral incisor of an 11-year-old boy. The talon cusps caused clinical problems that were related to caries or occlusal interferences. The presence of the dental anomaly in 2 members of the same family suggests that genetic inheritance may be a causative (related) factor. Examination of relatives could facilitate early diagnosis of the talon cusp and aid in preventing carious and occlusal problems.  相似文献   

13.
Intrabony migration of impacted teeth   总被引:1,自引:0,他引:1  
Shapira Y  Kuftinec MM 《The Angle orthodontist》2003,73(6):738-43; discussion 744
Intrabony migration of impacted teeth is a rare dental anomaly, which occurs only in the permanent dentition of the lower jaw. The teeth involved in this phenomenon are the mandibular lateral incisor, canine, and second premolar. Migration of the lateral incisor is usually in a distal direction, resulting in transposition with the canine. Migration of the canine is most frequently in a mesial direction, resulting in transmigration across the mandibular symphysis to the opposite side of the dental arch. The second premolar most often migrates distally, sometimes past the gonial angle and as far as the coronoid process. Surgical and orthodontic treatment options are presented for the three intrabony migrating teeth.  相似文献   

14.
BackgroundMorphological alterations in tooth structure involving either crown or root are common in the literature. But co-occurrence of multiple anomalies in a permanent mandibular central incisor is extremely rare.Case reportThis paper reports an unusual combination of multiple dental anomalies–talon cusp, dens invaginatus and macrodontia affecting both the crown and root of a permanent mandibular left central incisor of a 12-year old Indian boy. Case management has been described and the implications are discussed.ConclusionDiagnosis and treatment of teeth affected by multiple anomalies is a challenging proposition, requiring careful clinical and radiographic interpretation.  相似文献   

15.
Tooth transposition is a rare dental anomaly that is characterized by the interchanged position of two adjacent permanent teeth in the same quadrant or ectopic eruption of one tooth in the place of another. This article presents two case reports of transpositions. In the first case, a 21-year-old man presented with a left maxillary canine to molar site transposition. Radiographs showed that the canine was transposed completely. In the second case, a 35-year-old man presented with a right mandibular second premolar that had erupted between the first and second molars. Radiographs showed that the second premolar was positioned between the first and second molars. Maxillary canine to first molar site transpositions are extremely rare. To date, just eight cases have been reported in the English literature. Early loss of the first permanent molar may trigger distal migration of a developing canine bud. A mandibular second premolar erupting between the first and second molars is also a rare position anomaly that has not been reported in the English literature.  相似文献   

16.
The dental, genetic, radiological and dermatoglyphic findings of a 19-year-old girl showing macrodontia of maxillary permanent central incisors in association with a contrasting character, microdontia of maxillary permanent lateral and mandibular primary central incisors and bilateral absence of maxillary first premolars and missing of the right mandibular second premolar and peg-shaped mandibular primary lateral incisors and canines were presented.  相似文献   

17.
Summary. This is a report of two patients with isolated facial talon cusps. One occurred on a permanent mandibular central incisor; the other on a permanent maxillary canine. The locations of these talon cusps suggests that the definition of a talon cusp include teeth in addition to the incisor group and be extended to include the facial aspect of teeth.  相似文献   

18.
Abstract –  The talon cusp is a relatively uncommon dental anomaly manifested as an accessory cusp-like structure on the crown of anterior teeth. The presence of a talon cusp can cause clinical problems. This article reports the case of a patient presenting a talon cusp affecting the permanent maxillary right central incisor causing clinical problems related to caries, displacement of the tooth, occlusal position and tendency to dental traumatism. The management of this tooth included caries removal and reduction of the cusp. Pulp-capping with calcium hydroxide was required because of the presence of pulp horn extensions in the talon cusp.  相似文献   

19.
目的 确定不同恒牙(除第三磨牙外)的牙冠与牙根长度的发育完成时间,探讨牙冠与牙根长度发育完成时间的性别差异。方法 选择3304例3~18岁儿童与青少年全口曲面体层片,应用Haavikko法分别记录每个恒牙的发育分期,采用SPSS 25.0软件包计算男女不同恒牙的牙冠与牙根长度发育完成时间的中位数,利用Mann-whitney U检验进行男女性别间差异比较。结果 中切牙和第一磨牙的牙冠发育完成时间无性别差异,P值分别为0.143(上颌中切牙)、0.122(上颌第一磨牙)、0.191(下颌中切牙)和0.558(下颌第一磨牙),其余牙女性均显著早于男性。上颌中、侧切牙、第二前磨牙和第二磨牙的牙根长度发育完成时间无性别差异,P值分别为0.057、0.130和0.294;下颌中,第二前磨牙和第二磨牙的牙根长度发育完成时间无性别差异,P值分别为0.428、0.057;上、下颌其余牙牙根长度发育完成时间女性均显著早于男性。结论 恒牙牙冠与牙根长度发育完成时间女性普遍早于男性,上、下颌恒牙牙冠与牙根长度发育完成时间的性别差异相似。  相似文献   

20.
目的:观察正畸患者中伴有恒牙先天缺失、多生牙和锥形牙或过小牙的发生率及分布,并分析其相关性。方法:随机抽取正畸患者800例,男260例,女540例,年龄12-40岁。通过石膏模型和曲面断层片统计先天缺牙、多生牙、锥形牙或过小牙的发生率及分布。通过分类变量的关联性来分析多生牙和锥形牙或过小牙与先天缺牙的相关性,假设检验采用列联表的独立性x2检验,并采用Pearson列联系数r来描述两变量关联程度。结果:800例中发生恒牙先天缺失100例,发生率为12.5%。常见的缺失牙位从多到少依次为下颌侧切牙、下颌第二前磨牙、下颌中切牙、上颌侧切牙、上颌第二前磨牙。多生牙的发生率为3.1%,锥形牙或过小牙占8.3%。通过分类变量的关联性分析得出,锥形牙或过小牙的发生与先天缺牙有相关性,Pearson列联系数r为0.173。结论:正畸患者中恒牙先天缺失的发生率为12.5%,最常见的缺失牙位是下颌侧切牙和下颌第二前磨牙;正畸患者中恒牙先天缺失和锥形牙或过小牙的发生具有相关性。  相似文献   

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