下颌第三磨牙阻生类型同体两侧对称性研究

目的研究下颌第三磨牙阻生类型同体左、右对称性。方法收集186例下颌第三磨牙拔除病例数据。所有患者进行临床检查并拍摄曲面断层片。按照Pell—Gregory升支分类、Pell—Gregory牙争平面分类和Winter分类对左、右两侧下颌第三磨牙阻生类型分别进行分类。对两侧下颌第三磨牙阻生类型进行描述性统计分析和Speaman相关分析。结果三种阻生类型两侧完全对称者95例,占51．1％;任意两种阻生类型两侧均对称,另一种不对称者占19．9％;三种阻生类型中仅一种两侧对称,另两种不对称者占14．5％;三种阻生类型两侧均不对称者占14．5％。两侧下颌第三磨牙Pell—Gregory升支分类（r=0．51,P=0．01）、Pell—Gregory铪平面分类（r=0．41,P=0．01）和Winter分类（r=0．48,P=0．01）均有显著相关性,将每侧下颌第三磨牙三种阻生类型合并,两侧也具有显著相关性r=0．67,P=0．01）。结论同体两侧下颌第三磨牙阻生类型具有对称性,一侧下颌第三磨牙的阻生类型、临床病理以及治疗方案对另一侧具有指导意义。     

下颌阻生第三磨牙自然变化及其对邻牙的影响

下颌阻生第三磨牙拔与留的利弊究竟如何是许多学者研究的课题。本文就４０５例３０￣７０岁文化层次较高的受检者的下颌阻生第三磨牙自然变化及其对邻牙的影响作一调查分析。结果表明，三种阻生牙中，尤以近中阻生牙对自身与邻牙的危害最大（Ｐ〈０．００５）。垂直阻生牙是急性冠周炎的主要病源牙，应当拔除。４０岁以后，垂直阻生牙呈可萌出的趋势且对机体的危害风险下降，应予保留。近中阻生牙诱发第二磨牙远中和缺失者呈随年龄递     

下颌智齿近中阻生与第二磨牙远中面患龋关系的X线片分析

下颌智齿近中阻生与第二磨牙远中面患龋关系的Ｘ线片分析肖梅陈群叶西安市第四军医大学口腔医学院（７１００３２）下颌智齿近中阻生时如何防治第二磨牙远中患龋，仍有深入讨论的必要。本文根据Ｘ线片对此进行分析研究。１材料和方法门诊患者，随机任选有病历记载半年的下...     

下颌阻生智齿致邻牙牙髓炎的治疗

临床上下颌阻生智齿常致冠周炎，也可导致邻牙远中面和颈部龋、远中根吸收，乃至发展成牙髓炎，现略谈对此如何进行合理治疗的体会。１临床资料１．１病例选择选择智齿致第二磨牙牙髓炎１２例（男８例，女４例），年龄１９岁～２７岁，智齿无龋病，均为近中斜位阻生，Ｘ线...     

657例下颌阻生智齿的X线分析

下颌阻生智齿发生率高,常引起各种并发症。由于牙根形态的多变,拔除时常遇到困难。因此术前拍摄X线片对根形态、弯曲方向和骨组织情况作出大致估计,对手术会有帮助。为此我们收集了近九年来门诊患者下颌阻生齿的X线片657例进行分析,报告如下:     

气动涡轮钻拔除下颌阻生第三磨牙的探讨

笔者采用涡轮钻去除冠阻力法 ,对 15 2例不完全埋伏和完全埋伏的下颌水平阻生第三磨牙进行了拔除手术 ,取得了满意效果一、材料和方法1.临床资料 :本组 15 2例水平阻生齿均来自天津市口腔医院。男 10 1例 ,女 5 1例。年龄最大 41岁 ,最小 2 0岁。完全埋伏水平阻生齿 89例 ,不完全埋伏水平阻生 6 3例。左右两侧同为水平阻生的 18例 ,其余为单侧水平阻生。行软组织切开 ,翻起粘骨膜瓣者 143例 ,其中需去骨者 10 5例 ,未做软组织切开的 9例。2 .设备 :采用日本产贝尔蒙综合治疗台、派那埃阿西格玛 40 0 0 ,0 0 0ｒｐｍ高速气动涡轮手机。机头直…     

下颌智齿阻生对邻牙远中龋的影响

有文献报道,在现代人群中下颌智齿阻生率为52.3％。阻生智齿可引起多种并发症,其中下颌第二磨牙远中龋是最常见之一,但具体下颌第二磨牙远中龋与智齿各种阻生情况之间的关系及病因未见资料报道。本文通过对107例患者78的临床检查及X线分析对此作了初步探讨。     

下颌第三磨牙低位埋伏阻生致邻牙牙根吸收1例

临床资料患者,男,28 岁,因右下后牙区反复发炎就诊.检查见:48远中颊尖破龈萌出,冠周牙龈无急性炎性表现.X 线全颌曲面体层片显示:48 前倾低位埋伏阻生,牙冠近中部分嵌入47 远中根部,48牙冠与47 根部有明显线状透射影.     

下颌第二磨牙远中邻面龋危险因素研究

目的研究导致下颌第二磨牙远中邻面龋的危险因素。方法收集558例下颌第三磨牙拔除病例数据,将下颌第二磨牙远中邻面龋与下颌第三磨牙的阻生类型、患者性别、年龄以及牙位等变量之间进行Logistic回归分析。结果 558例下颌第三磨牙拔除病例中,120例出现远中邻面龋。下颌第三磨牙阻生类型中的Pell-Gregory牙合平面分类（P=0.00〈0.01,OR=0.43〈1）和Winter分类（P=0.00〈0.01,OR=2.45〉1）以及性别（P=0.00〈0.01,OR=1.99〉1）、年龄（P=0.00〈0.01,OR=1.06〉1）进入Logistic回归方程。结论下颌第三磨牙在下颌骨内的位置越高,近中倾斜的角度越大,越容易导致下颌第二磨牙远中邻面龋。年龄越大,下颌第二磨牙远中邻面龋发生率越高,男性较女性更容易发生第二磨牙远中邻面龋。     

下颌阻生智齿拔除术后干槽症的病因Logistic分析

下颌阻生智齿拔除术后干槽症的病因Ｌｏｇｉｓｔｉｃ分析薛振恂（１）毛天球（２）夏结来（２）（第四军医大学１口腔医学院颌面外科２医学统计教研室）下颌阻生智齿拔除术后干槽症的发生率很高，在１０％～３０％之间。１８９６年Ｃｒａｗｆｏｒｄ首先报告本病，近百年来...     

A preliminary radiographic study of mandibular para-radicular third molar radiolucencies

OBJECTIVES: To determine the frequency and describe a poorly documented radiographically observed variation of normal associated with the roots of mandibular third molars--the mandibular third molar para-radicular radiolucency (MPR). STUDY DESIGN: A systematic random sample of 822 dental school surgery and emergency charts was reviewed for radiographic evidence of the MPR. The frequency was determined and the variation in radiographic appearance was described. Clinical signs and symptoms were correlated with the presence of an MPR. RESULTS: The frequency of the MPR was 7.8% with a female-to-male ratio of 2.6:1.0. Of 6 bilateral cases (9.4%) all occurred in female patients. The most common location was the distal surface of the mandibular third molar. Most (58.6%) were oval in shape. CONCLUSION: This radiographic finding most likely represents a variation of normal anatomy and based on this retrospective study does not appear to require treatment.     

下颌阻生第三磨牙拔除术后邻牙远中骨缺损的CBCT评价

目的: 分析成人下颌阻生第三磨牙（impacted mandibular third molar, impacted M3M）拔除术后6个月的第二磨牙（mandibular second molar, M2M）远中骨缺损变化及其影响因素。方法: 回顾性分析已拔除阻生M3M的25例患者（37颗M3M）的术前及术后6个月CBCT资料。采用SPSS 25软件包进行数据统计,采用重复测量方差分析比较手术前、后M2M远中骨缺损深度变化,采用独立样本t检验分析其影响因素。结果: M2M术后6个月远中骨缺损深度减少,骨高度相比术前改善;年龄、阻生类型是影响M2M术后6个月骨缺损的因素。结论: 年轻患者高风险M3M拔除后,M2M远端的骨高度有所恢复;年龄、阻生类型是其影响因素。当M3M需要拔除时,早期拔除可能对M2M的牙周健康产生有益影响;如M3M为低位阻生,应同期植入骨移植材料,以期获得更好的远中骨愈合。     

Association between the presence of a partially erupted mandibular third molar and the existence of caries in the distal of the second molars

The objective of this study was to verify, using periapical radiographs, whether a partially erupted mandibular third molar is a factor in the presence of dental caries on the distal surface of the adjacent second molar. Two-forty six high quality periapical radiographs were selected, each showing a partially erupted mandibular third molar. The variables analyzed were: tooth number; gender; age; radiographic presence of caries on the distal surface of the adjacent molar; Pell and Gregory classification; Winter classification; angulation and distance between the second and mandibular third molar. The examiners were previously calibrated to collect data (kappa statistics from 0.87 to 1.0). The prevalence rate of caries on the distal surface of the second molar was 13.4%. In the logistical multivariate regression analysis, the angulation (OR=8.5; IC95%: 1.7-43.8; p=0.011) and the gender (OR=3.3; IC95%: 1.4-7.7; p=0.005) remained statistically significant after an age adjustment was made. The results indicate that the presence of a partially erupted mandibular third molar with an angulation of 31 degrees or more, is a risk factor for caries on the distal surface of the mandibular second molars.     

下颌阻生第三磨牙拔除术对下颌第二磨牙远中牙周组织的影响

下颌阻生第三磨牙拔除后可能遗留下颌第二磨牙远中根的牙周组织缺损,其发生及预后受年龄、第三磨牙的阻生状态、术前局部的感染情况、术前邻牙状况等因素的影响. 拔牙时年龄较大、低位阻生、术前存在冠周感染或反复食物嵌塞、邻牙龋坏等因素将使这种牙周骨质缺损加剧且预后不佳. 从预防的角度,尽可能在小于25岁的低龄期拔牙,有利于阻止这种不良反应的发生或加剧;进行骨质移植可以有效促进术后第二磨牙远中牙周骨质缺损的修复.     

Residual periodontal defects distal to the mandibular second molar 6-36 months after impacted third molar extraction

AIM: This retrospective study investigated the periodontal conditions distal to mandibular second molars 6-36 months after routine surgical extraction of adjacent impacted third molars. METHOD: Subjects were randomly selected by systematic sampling from computer records of 3211 surgical mandibular third molar extractions in the Hong Kong dental teaching hospital. Records and pre-extraction radiographs of the selected cases were retrieved. Selected subjects (n = 283) were invited for an interview followed by a clinical examination. Community Periodontal Index (CPI) protocol was used for the assessment of the general periodontal status (excluding the mandibular second molar of interest, i.e. the subject tooth) followed by a detailed periodontal examination of the subject tooth. RESULTS: In all, 158 subjects, aged 29 +/- 7 years, were examined with only 6% (nine subjects) having a highest CPI score of 4 (excluding the subject tooth), but local periodontal defects were prevalent at the distal surface of subject mandibular second molars: mean probing pocket depth (PPD) was 5.4 +/- 1.9 mm with 67% (106 subjects) exhibiting PPD >or= 5 mm and 23% (36 subjects) exhibiting PPD >or= 7 mm; mean recession was 0.8 +/- 1.0 mm; bleeding on probing 96% and suppuration on probing 5%. Multiple linear regression analysis was used to analyse the effects of 12 independent variables on the PPD at the distal surface of the involved mandibular second molar. Three possible risk indicators (P < 0.001, R2 = 0.27) associated with localised increased PPD at the distal surface of the mandibular second molars were identified: 1) third molar 'mesio-angular' impaction; 2) pre-extraction crestal radiolucency and 3) inadequate post-extraction local plaque control. CONCLUSION: The results suggest that periodontal breakdown initiated and established on the distal surface of a mandibular second molar in the vicinity of a 'mesio-angular' impacted third molar evidenced by pre-extraction crestal radiolucency in association with inadequate plaque control after extraction can predispose to a persistent localised periodontal problem.     

下颌第二磨牙龋损状况临床分析

目的: 统计分析下颌第二磨牙龋坏始发部位及严重程度, 并分析其与性别、年龄及下颌第三磨牙萌出状况的关系。方法: 采用临床与X线检查对481例下颌第二磨牙龋坏患者进行统计调查, 应用SPSS 13.0软件包对结果进行χ2检验。结果: 下颌第二磨牙龋坏多始发于面和远中邻面, 其次为颊面, 发生率分别为33.8%、33.2%、24.4%;累及牙髓的龋坏最多, 占49.7%, 深龋、浅中龋分别占31.7%、18.6%;男、女性别在龋坏部位分布总体上无显著差异;年龄与下颌第二磨牙的龋坏部位分布及严重程度有显著的相关性, 随着年龄增大, 面和远中邻面龋坏增多, 程度加重;下颌第三磨牙萌出状况对下颌第二磨牙龋坏影响显著。结论: 下颌第二磨牙始发龋坏牙面以面及远中邻面最多, 龋损程度严重, 年龄、下颌第三磨牙萌出状况与龋坏状态关系密切。预防性拔除异常萌出的下颌第三磨牙及定期检查, 是预防和早期治疗下颌第二磨牙龋坏的有效措施。