下颌双侧第四磨牙近中阻生1例

<正>第四磨牙是临床中较为少见的一种多生牙的类型,国内外文献偶有报道关于上颌或下颌单侧第四磨牙阻生的病例,而双侧下颌第四磨牙近中阻生的病例国内外罕见文献报道。现将我科诊治的1例病例报道如下。     

第二乳磨牙与第二前磨牙易位埋伏阻生1例

牙阻生常见于恒牙列,乳牙列罕见。本文对 1例下颌第二乳磨牙与第二前磨牙易位埋伏阻生的病例进行报道。     

下颌阻生智齿与第二磨牙患龋关系的探讨

本文收集下颌智齿阻生且同时有下颌第一、二磨牙的患者 112 0例 ,从性别、年龄、智齿阻生方向及在口内存留时间等方面 ,统计分析对下颌第二磨牙患龋的影响 ,并与同组病例下颌第一磨牙患龋率对照 ,现报告如下。临床资料门诊下颌智齿阻生病人 112 0例 ,下颌第一、二磨牙各2 180颗 ,男 989颗牙 ,女 1191颗牙 ,年龄 18～ 48岁。用口镜、镊子、探针、Ｘ线片或拔除阻生智齿等方法 ,检查智齿阻生方向及下颌第一、二磨牙患龋情况 ,询问阻生智齿萌出时间 ;智齿阻生方向按其长轴与下颌第二磨牙长轴关系分为垂直阻生、水平阻生、近中阻生、颊向阻生、舌…     

右下恒磨牙与畸形多生牙融合伴根尖吸收1例

融合牙通常由2颗相邻牙牙本质发生融合,在乳牙和恒牙列中均可发生,发生于恒磨牙的融合牙十分罕见。本文报道右下第一恒磨牙与畸形多生牙融合伴根尖吸收并发慢性根尖周炎1例,就其临床检查与影像学检查进行阐述。通过文献的回顾,将其病因、治疗方式等进行探讨。     

上颌中切牙埋伏阻生的病因与诊断

上颌中切牙在生理功能、心理健康方面均起着特殊重要的作用 ,中切牙埋伏阻生一直是口腔科临床研究的重点和难点之一[1,2 ] 。研究中切牙埋伏阻生的病因与诊断对开展预防和治疗具有重要意义。本文从临床角度对上颌中切牙阻生的病因及诊断进行初步探讨。材料与方法1 病例收集　收集近几年在我院正畸科及儿童牙科就诊 ,经病史询问、临床检查、Ｘ线片检查确诊为上颌中切牙埋伏阻生的病例 40例 ,年龄 7～ 13岁 ,男 2 2例 ,女 18例。2 诊断标准　健侧中切牙已萌出并与下切牙建立覆牙合、覆盖关系 ,或者Ｘ线片显示上颌恒中切牙牙根已发育完成但牙…     

下颌前倾或水平阻生磨牙的简捷快速竖直

下颌前倾或水平阻生的磨牙临床上多予以拔除,笔者对于牙列较整齐、下颌第二磨牙阻生或经正畸减数治疗后上颌第三磨牙位置正常、下颌第三磨牙阻生者仅采用与阻生磨牙相邻的磨牙作支抗牙,黏接焊接了多曲推簧的磨牙带环,推阻生磨牙向远中、牙合向移动,引导前倾或水平阻生的下磨牙竖直、萌出.结果显示前倾或水平阻生的下颌磨牙较快地被竖直、萌出到正常的牙合平面,建立良好的牙合关系,X线曲面断层片示原阻生牙冠所占的位置为正常牙槽骨组织所代替.该方法能有效地使前倾或水平阻生的下颌磨牙产生快速的远中牙合向旋转运动,具有无须手术暴露阻生磨牙颊面、操作简单、竖直时间短、患者无明显不适和创伤小等优点.     

固定式磨牙竖直器矫正下磨牙前倾阻生

下磨牙前倾阻生是临床上常见的错畸形。其危害主要有：1）易滞留食物,导致其自身及邻牙的龋病。2）当该牙因阻生而低于平面时,常导致对牙伸长,从而导致关系的进一步紊乱。为有效地竖直前倾阻生的下磨牙,特设计了固定式磨牙竖直器。     

下颌第二磨牙阻生的病因及治疗方法

在正畸临床上,下颌第二磨牙的阻生虽然不如第三磨牙、上颌尖牙和下颌第二前磨牙的阻生来的常见,但是一旦发生,不但影响患者的咀嚼功能和牙弓的稳定性,还容易引起其近中邻牙的远中邻面龋,甚至牙髓根尖周病的发生。本文就近年来的一些相关文献报道进行归纳总结,就下颌第二磨牙阻生的病因和治疗方法作一综述。     

正畸弹性分牙圈直立阻生下颌第二恒磨牙

16岁女性患者．主诉下颌第二恒磨牙区反复发作的自发性疼痛,检查发现其病因为下颌第二恒磨牙前倾阻生。本文报告了一种简单的利用正畸弹性分牙圈直立阻生磨牙的方法。     

区段截骨即刻复位结合正畸精细调整治疗恒磨牙阻生：临床病例报告

恒牙萌出紊乱对临床医师来说是一个挑战．如后牙阻生引起的侧方开骀即可能严重影响患者的咬合功能。本病例报告介绍了一种通过外科区段截骨结合正畸精细调整治疗恒磨牙阻生的方法。采用一步或两步法单牙区段截骨术．将两颗处于不同萌出阶段的阻生恒磨牙复位到骀平面，术后再通过正畸手段将牙一牙槽骨段调整到理想的咬合位置。     

Risk of osteoradionecrosis after extraction of impacted third molars in irradiated head and neck cancer patients.

PURPOSE: This study was performed to compare the risk of osteoradionecrosis (ORN) in head and neck cancer patients in whom 1 or more impacted third molars were extracted before radiotherapy with patients whose impacted third molars were left intact. PATIENTS AND METHODS: Eighty-one patients were selected from the medical records from 1989 to 1998. Patients had at least 1 impacted third molar and received radiotherapy for a head and neck cancer. These patients were divided into 2 groups on the basis of preirradiation extraction: group 1, patients who had impacted third molars extracted before radiotherapy (n = 55), and group 2, patients whose impacted third molars were left intact before radiotherapy (n = 38). In 12 patients of combined groups 1 and 2, at least 1 but not all of the impacted third molars were extracted before radiotherapy. RESULTS: Before radiotherapy, a total of 99 impacted third molars were extracted from the 55 patients in group 1 and a total of 55 impacted third molars were left intact in the 38 patients in group 2. After radiotherapy, a total of 7 impacted third molars were removed from 5 patients as treatment for infection (5 lower molars) or discomfort (2 upper molars). A total of 4 patients (2 from group 1 and 2 from group 2) developed ORN in the mandible. Of these 4 cases of ORN, 1 from group 1 appeared to be related to a dry socket that developed after preirradiation extraction of a lower impacted third molar, 1 from group 2 seemed to be related to infection of a lower impacted third molar after radiotherapy, and the remaining 2 cases appeared to be unrelated to an impacted third molar. CONCLUSION: Because few patients in this study developed ORN, the study failed to demonstrate whether preirradiation extraction versus retention of impacted third molars affects the risk for ORN.     

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后牙的埋伏阻生与前牙比较,不论在矫治理念,还是矫治设计上都有较大的不同。本文重点介绍了上、下颌前磨牙埋伏阻生的原因和矫治方法,上、下磨牙,尤其是第三磨牙埋伏阻生的处理。后牙埋伏阻生的治疗主要从功能考虑,对美观影响不大。对导萌困难的病例,选择拔牙矫治也是可以接受的。拔除无法保存的第一或第二磨牙后,第三磨牙的导萌或前移可以进入功能位置。     

Bilateral root resorption of maxillary first permanent molars by unerupted second molars associated with orthodontic distalisation

Root resorption is a common but undesirable side-effect of orthodontic treatment. It is a well-recognised phenomenon largely associated with impacted or unerupted teeth and in most cases, is mild and does not affect longevity of the affected teeth. This case report of a medically fit and healthy Caucasian boy who was undergoing orthodontic treatment at the Eastman Dental Hospital, UCLH (EDH) for management of his severe hypodontia, presents an unusual incident of bilateral resorption of his maxillary first permanent molars by the unerupted second molars. The near end-of treatment radiographs showed that both upper second molars were mesio-angularly impacted and resorbing the first molars; however, the patient reported no associated signs or symptoms. Bilateral Cone Beam Computed Tomography radiographs were requested for the posterior maxillary arch in the area of the molar dentitions and extensive root resorption affecting the first molars caused by the crown of the mesio-angularly impacted second molars was evident. This unusual bilateral root resorption of maxillary first molars associated with unerupted second molars is an uncommon presentation, with no similar case reports found in the literature. Great emphasis should be placed on informed valid consent and potentially making the patient aware of the small but potential risk of resorption of erupted terminal molars where orthodontic molar distalisation is considered.     

磨牙后区微种植体支抗竖直下颌近中阻生第二磨牙的临床应用

目的探讨磨牙后区微种植体应用于下颌近中阻生第二磨牙竖直的正畸治疗方法,评估其效果。方法选择南京医科大学附属口腔医院正畸科2011—2014年门诊下颌第二磨牙近中阻生的患者13例23颗患牙,采用磨牙后区植入微种植体,牵引23颗患牙向远中移动,引导其竖直、萌出。结果 23颗阻生的下颌第二磨牙全部竖直萌出并建立良好的咬合。竖直治疗平均时间为6.5个月。结论磨牙后区微种植体支抗能简单有效地竖直下颌阻生的第二磨牙,并且可以控制磨牙的垂直向高度,避免对相邻牙齿产生不良影响。     

Surgical management of impactedthird molars

Teeth may become impacted when they fail to erupt or develop into the proper functional location. As such, impacted teeth are considered nonfunctional, abnormal, and pathological. The mandibular third molar is the most common tooth to become impacted. The cause of impacted third molars is thought to be inadequate space. Several studies indicate that a change from a coarse, attritive diet to a modern, refined diet has lead to an increased incidence of impacted teeth. Interproximal attrition allows for greater mesial migration of teeth and space for third molar teeth. Teeth that fail to attain a functional position may be pathological and should be considered for removal. The indications for removing impacted teeth can be divided into those of acute or chronic pathology. Impacted third molars are often associated with pain, infection, cyst formation, benign tumors, root resorption, bone loss, periodontal disease, and caries. The decision to surgically remove impacted third molars is often unclear. There are no absolute treatment protocols established. The dentist must consider a variety of factors and make an informed decision with the patient. Most experienced clinicians combine objective data and common sense to arrive at a logical treatment plan. The purpose of this article is to discuss factors related to impacted teeth and help the orthodontist understand the general management of impacted third molars. The decision for surgery will be assisted by an understanding of all of the risk factors associated with impacted teeth and presenting the options to the patient.     

下颌第二、第三磨牙并列阻生的正畸矫治

目的探讨下颌第二、三磨牙并列阻生的正畸治疗方法,评估其效果。方法选择下颌第二、第三磨牙并列阻生患者6例、共8对,拔除下颌阻生第三磨牙,采用固定矫治器结合磨牙带环焊多曲推簧直立装置,对水平阻生的第二磨牙进行竖直,使第二磨牙远中直立移动。结果水平阻生第二磨牙全部被直立,达到正常的殆平面,获得良好功能邻接关系及根平行。X线片示原阻生牙冠所占空间为正常牙槽骨组织所修复。下颌阻生磨牙竖直时间为5～14个月,平均为8．63个月。结论在下颌第二、三磨牙并列阻生患者中,拔除下颌第三磨牙,有利于第二磨牙的直立。自制带环焊多曲推簧及粘接拉钩的磨牙竖直技术能有效地使水平阻生的第二磨牙产生快速的远中直立移动。     

下颌磨牙阻生的正畸治疗

目的探讨下颌前倾、水平阻生磨牙的正畸治疗方法，评估其效果。方法采用固定矫治器结合磨牙带环焊多曲推簧，推14颗水平阻生或前倾阻生的下颌磨牙远中向、[牙合]向移动，引导其竖直、萌出。结果前倾、水平阻生的下磨牙全部竖直萌出到正常的[牙合]平面并有良好的[牙合]接触关系。X线片显示原阻生牙牙冠所占位置被正常牙槽骨组织所代替。竖直治疗时间为6～12个月，平均7．4个月。结论带环焊多曲推簧的磨牙竖直技术能有效地使前倾、水平阻生的下颌磨牙产生快速的远中向、[牙合]向旋转运动，具有创伤小、操作简单、患者易适应等优点。     

Variations in impacted mandibular permanent molars: Report of three rare cases

The impaction of permanent teeth is not uncommon, but few permanent teeth are rarely impacted like mandibular first and second molars. Though third molars are commonly impacted, inversely impacted mandibular third molars are very rare. Here, we report three unusual cases of impacted mandibular molars accidentally diagnosed on conventional radiographs.     

处理无症状第三磨牙的循证思考

第三磨牙是最易发生阻生的牙齿,与多种病变形成有关,临床上主要的治疗方法为拔除。虽然国际上对有症状第三磨牙的拔除已达成共识,但就无症状第三磨牙是否应当预防性拔除仍存在争议。循证医学要求医生对患者的诊断和治疗必须基于当前可得到的最佳临床研究证据,以保证患者得到当前最好的治疗效果。本文通过对近年来文献中关于第三磨牙拔除适应证、无症状第三磨牙可能发生的病变以及第三磨牙拔除风险等方面的内容进行综述,以便在处理无症状第三磨牙的决策制定中作出基于证据的合理选择。