上颌第一前磨牙三根管1例

1病例报告患者男,50岁,主诉右上后牙冷热刺激痛1个月余,临床检查发现右侧上颌第一前磨牙颊侧牙颈部深龋洞,探痛( ),冷热刺激痛,叩痛(±),无松动,牙龈、牙冠形态正常,诊断为14慢性牙髓炎,拟行牙髓失活加根管治疗术。根管预备时发现该牙共有颊侧2个、腭侧1个共3个根管,根管型为3-3-3;舌侧根管较为粗大且直,颊侧二根管细弯但尚通畅,电子根尖定位仪确定工作长度分别为:腭根20.0mm,近颊根18.0mm,远颊根18.2mm,常规根管预备后一次法根管充填,治疗后无明显根充反应,症状消失无不适。2讨论上颌第一前磨牙根管系统以双根管多见,单根管较少,偶有3个根…     

双侧上颌第一前磨牙3根和左下颌第一前磨牙3根融合1例

患者,男,24岁,因正畸治疗需要拔除双侧上下颌第一前磨牙。术前曲面体层片示双侧上颌第一前磨牙和左下颌第一前磨牙牙根异常。拔牙术前检查见发现牙冠形态均正常,双侧上颌第一前磨牙阻力均较大,拔除后发现:双侧上颌第一前磨牙均为3根(2个颊根和1个腭根),离体下开髓均为3根管;左下颌第一前磨牙为融合3根,可见明显沟状凹陷;右下颌第一前磨牙为融合双根(图1)。左侧上颌第一前磨牙因颊侧2根舌向弯曲明显,拔除时颊侧2根折断。左侧下颌第一前磨牙离体下开髓,发现其近颊根和腭根融合,远颊根为单一根管。拔牙术后摄左右双侧上颌第二前磨牙根尖片,左侧上颌第二前磨牙疑3根影像。     

第一前磨牙髓室解剖形态的研究

目的研究第一前磨牙髓室形态,为活髓牙牙体预备提供相关数值。方法收集上下颌第一前磨牙各30颗,用游标卡尺测量颊舌向剖面牙颈部、颊舌侧髓角处、中央窝至髓室顶的牙体组织厚度。结果上颌第一前磨牙颊尖至颊侧髓角（5.09±0.50）mm,下颌第一前磨牙颊尖至颊侧髓角（4.68±0.57）mm。结论第一前磨牙的颊侧髓角较高,接近牙冠的中1/3,颈部髓室近远中壁薄,在牙体预备时特别注意邻面中1/3偏颊侧区域,避免意外穿髓。     

颌第一前磨牙三根管1例

1 病例报告 患者男,50岁,主诉右上后牙冷热刺激痛1个月余,临床检查发现右侧上颌第一前磨牙颊侧牙颈部深龋洞,探痛(+),冷热刺激痛,叩痛(±),无松动,牙龈、牙冠形态正常,诊断为14慢性牙髓炎,拟行牙髓失活加根管治疗术.根管预备时发现该牙共有颊侧2个、腭侧1个共3个根管,根管型为3-3-3;舌侧根管较为粗大且直,颊侧二根管细弯但尚通畅,电子根尖定位仪确定工作长度分别为:腭根20.0 mm ,近颊根18.0 mm,远颊根18.2 mm,常规根管预备后一次法根管充填,治疗后无明显根充反应,症状消失无不适. 2 讨论     

前牙、前磨牙开髓位置的探讨

临床上经常见到前牙和前磨牙因深龋或重度楔形缺损而致唇颊面颈部严重缺损,引起牙髓坏死,并发尖周炎.对这类患牙进行根管治疗术时,开髓位置的选择是一个棘手的问题.如按常用的在患牙舌(腭)侧或合面开髓,就破坏较多健康牙体组织或导致牙颈部折裂.现在多年实践中摸索出从唇颊面中央开髓进路的方法,顺利完成根管治疗术和牙体修复.     

上颌第一前磨牙三根三根管1例

患者,女,16岁,因正畸治疗需要,设计拔除4颗第一前磨牙。在拔上颌第一前磨牙时感觉牙脱位困难,拔除后发现该牙有三个牙根,颊侧2个根,腭侧1个根,其中近颊根与远颊根部分融合,且每个牙根都有独立的根管,属单根单根管型（图1）。     

纤维桩对穿髓型楔状缺损抗折性修复的临床对比观察

目的：针对穿髓型楔状缺损牙颈部抗力薄弱易折断的潜在隐患,评价不同修复术式对牙颈部抗折性能的临床效果。方法：临床随机选择穿髓型楔状缺损患者48例,（牙合）面完整,男性20例,女性28例,年龄45-73岁。其中第一前磨牙28例（上颌19例,下颌9例）,第二前磨牙9例（上颌6例,下颌3例）;尖牙11例（上颌8例,下颌3例）。在（牙合）面开髓根管治疗后,将所有患者随机分为A、 B两组各24颗牙,以2种术式分别进行修复。 A组：（牙合）面及楔状缺损处以Filtek Z350 XT纳米树脂完成修复; B组：根管纤维桩粘固后（牙合）面及楔状缺损处以Filtek Z350 XT纳米树脂完成修复。结果：临床观察2年, A组出现6例颈部折断, B组未出现颈部折断,经卡方检验连续校正公式计算,χ^2=4.68, P〈0.05,说明是否使用纤维桩修复与牙颈部折断间有统计学差异,使用纤维桩可增强牙颈部抗折断力。结论：在穿髓型楔状缺损根管内粘固玻璃纤维桩的一端,再以复合树脂将纤维桩的另一端与牙冠粘接,使纤维桩、树脂、整个牙齿（冠与根）三者整合为一体,不但增强了颊颈部修复体的固位,更提高了牙颈部的抗折性能,是一种合理、微创的牙颈部抗折修复形式,较好地体现了整体修复理念。     

左上颌第二磨牙2根管1例

男42岁,因左上颌后牙胀痛来我科就诊。检查:27远中邻面龋,近髓,未探及露髓孔,冷热刺激(-),牙髓活力检测(-),叩痛( )。诊断为27根尖周炎,采用根管治疗术。在开髓、探查根管口时发现远中颊侧根管口不明显,X线牙片显示该牙只有颊侧与腭侧二个根管。上颌第二磨牙多为近中颊、远中颊     

上颌第一前磨牙髓腔形态的影像学研究

目的:利用RVG(radio visio graphy)数字化X线成像系统测量上颌第一前磨牙髓腔解剖形态的相关数值,为临床诊断、治疗提供重要参考依据。方法:收集拔除的上颌第一前磨牙70颗,牙齿发育完全、根尖完整,用RVG数字成像系统分别拍摄近远中向数字X线片,在图像上测量髓腔形态的相关数值。结果:上颌第一前磨牙颈部髓室的颊腭向厚度(4.34±0.49)mm,颊尖至颊侧髓角之间的距离(5.84±0.58)mm,腭尖至腭侧髓角之间的距离(5.95±0.56)mm;牙尖至髓顶的距离(7.62±0.75)mm,牙尖至髓底的距离(10.38±1.44)mm;髓室高度(2.98±0.98)mm;髓顶至根分叉的距离(7.67±1.79)mm,髓底至根分叉的距离(4.59±1.48)mm。2根管口之间的距离(3.22±0.76)mm,2根管根中1/2之间的距离(3.71±1.43)mm,2根尖孔之间的距离(3.91±2.23)mm。结论:提供成人上颌第一前磨牙髓腔解剖的形态特征,为临床诊断和治疗时参考。     

上颌第一前磨牙根管颊舌向弯曲情况的研究

目的研究上颌第一前磨牙根管颊舌向的弯曲情况。方法选择100个上颌第一前磨牙为研究对象,开髓并充分暴露根管口后,将1个K型锉插入根管内直至根尖孔处。利用数字成像系统（RVG）拍摄每个牙的近远中向影像,采用Schneider法测量根管的弯曲角度,计算弯曲半径和弯曲部分长度。结果1）100颗上颌第一前磨牙共有176个根管,88个根管存在颊舌向弯曲,其中53个位于根尖1/3;21个根管存在“S”形弯曲,其第一弯曲多见于根中1/3,第二弯曲均见于根尖1/3处。2）颊腭侧根管弯曲情况无统计学差异（P>0.05）,但“S”形根管第二弯曲的弯曲情况更为复杂。3）弯曲角度与弯曲半径无相关关系（r=0.002,P>0.05）,但与弯曲部分长度呈正相关关系（r=0.489,P<0.01）。结论上颌第一前磨牙根管颊舌向弯曲发生率较高,其中“S”形根管的弯曲情况更为复杂。     

Evidence of the validity of a model of determinants of quality of restorative dental care

A model describing the relationship between self-reported quality of restorative dentistry and dentist characteristics for 119 Montana general dentists is presented. The best predictors formed a significant model explaining 22% of the variance of the quality measure. Results are contrasted with a previous estimation of the model for 102 Washington general practitioners. Evidence for the external validity of the model is presented.     

不同剂型玻璃离子水门汀溶解性比较研究

目的:研究、比较不同剂型玻璃离子水门汀的溶解性和表面微观形态改变,为临床使用提供依据.方法:将3M树脂加强型玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(水粉剂型)及GC玻璃离子水门汀(双糊剂型)分别在人工唾液中浸泡30 d,冷热循环15000次,烘干测重,比较前后质量变化,计算溶解率,并用扫描电镜观察表面微观改变.结果:不同剂型的玻璃离子水门汀溶解率由高到低分别为3M树脂加强型玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(双糊剂型).3种玻璃离子水门汀经浸泡溶解后,SEM扫描表面微观形态可观察到GE玻璃离子水门汀(双糊剂型)表面形态改变较少,其他2组玻璃离子水门汀表面微观改变较多.结论:双糊剂型玻璃离子水门汀理化性能及溶解率均低于传统水粉剂型,是未来临床修复治疗的的良好选择.     

Design of clinical trials of traditional therapies of periodontitis

The present paper on the design of clinical trials of periodontal therapy first addresses the issue of the etiology of periodontal disease. It is suggested that most if not all forms of destructive periodontal disease are caused by microorganisms and that there are different forms of disease with different microbial etiologies. The progressive nature of destructive periodontal disease is subsequently discussed and it is emphasized that, in a given patient, periodontal sites which show signs of inflammation and attachment loss may not over a period of several months and years show further sign of attachment loss. The present methods of assessing periodontal disease do not allow us to discriminate between potentially active and inactive sites in untreated patients. The significance and variability of indicators of periodontal disease such as bleeding on probing, probing pocket depth and probing attachment level measurements are discussed. The errors inherent in the various measurements are analyzed and suggestions are presented describing how alterations in any of the above parameters could be identified and presented in a clinical trial. Of concern for the statistical analysis of clinical data of periodontal disease is the definition of the "experimental unit". For a number of years, the "experimental unit" in periodontal trials was the patient. It is clear, however, that different sites within the same individual show different patterns of disease progression and lesion morphology and often respond differently to periodontal therapy. Statistical analyses must consequently be designed which recognize differences in site-to-site infection and lesion morphology within a common host. Until such analyses are available, the investigator should be wary of pooling data within the same individual, since such pooling may obscure meaningful alternatives which may take place in individual periodontal sites. Some goals of periodontal therapy are subsequently identified. 4 goals are discussed more in detail, namely: to establish conditions which will allow the patient to maintain a dentition without further breakdown of the periodontium; to reduce pocket depth to establish an anatomy in the dentogingival region which with proper maintainance care will prevent the re-establishment of the subgingival infection; to gain attachment as a result of treatment; to assess the effect of a certain chemotherapeutic agent on periodontal disease.     

Evaluation of efficacy of chemiluminescence for diagnosis of leukoplakia

ObjectiveLeukoplakia is the most common potentially malignant disorder preceding oral cancer. Chemiluminescence has been developed as an adjunct to conventional examination for the diagnosis of these potentially malignant disorders. This study was conducted to assess the efficacy of chemiluminescence in the diagnosis of leukoplakia and to compare the results with histopathological examination.Study designA total of 50 patients with leukoplakia were included from the outpatients attending the Department of Oral Medicine and Radiology, Dental Hospital, Bengaluru, Karnataka, India. These patients were subjected to conventional oral examination followed by chemiluminescent examination with Vizilite (Zila, Fort Collins, CO, USA) and biopsy for histopathological confirmation.ResultsThe sensitivity, specificity, positive predictive value, and negative predictive value of chemiluminescence were 93.75%, 55.56%, 78.95%, and 83.3%, respectively. The overall accuracy of chemiluminescence was 80%. A statistically significant association was observed between histopathology results and chemiluminescence results.ConclusionAlthough it is an easy, safe, minimal time consuming, and noninvasive technique, it has only adjunctive utility and it does not replace biopsy for the diagnosis of leukoplakia.     

《口腔医学》杂志2007年度有关信息的分析

目的通过对《口腔医学》2007年全年文献的回顾和分析,了解我国口腔临床医学的研究现状。方法阅读2007年《口腔医学》全年的文献,对各种信息进行了分类汇总,根据设计类型对临床一次性文献进行了分类,并对其中的试验性研究文章进行质量分析。结果《口腔医学》2007年全年的一次性文献274篇,基础和临床文献分别为108和166篇,以临床文献为主(60.58%)。在临床研究文献中,属于观察性、分析性和试验性的文献分别为97、9和60篇,观察性文献所占比例为36.14%,高于以往的报道。60篇观察性文献中,全都设有对照;统计方法应用得当者44篇;真正做到随机、盲法的分别只有4和2篇。结论我国口腔临床方面的研究水平近年来提高明显,但设计的科学性方面有待提高。     

正畸患者切牙影像失真发生情况分析

目的研究正畸患者曲面体层片上的切牙影像失真发生情况，并分析其原因。 方法从中山大学附属口腔医院放射科影像数据库中选取500例正畸患者的曲面体层片和头影测量侧位片，所有曲面体层片均采用咬合杆投照，分别从切牙牙体影像放大、缩小、牙根变短、根尖模糊等评价指标分析上下颌切牙影像失真的发生情况，在头影测量侧位片上测量中切牙根尖-对颌切牙切缘的距离，探讨切牙影像失真发生的原因。采用SPSS 19.0统计软件对所得数据进行统计学检验。 结果500例患者中，切牙牙体影像正常者共417例，切牙牙体影像失真者共83例，影像失真发生率16.6%，其中切牙牙体影像放大17例、牙体影像缩小0例、牙根变短30例，牙根影像变短伴模糊36例。影像失真患者的根尖-切缘距离大于影像正常的患者，差异有统计学意义（F = 5 187.18，P = 0）；影像失真患者的覆盖值大于影像正常的患者，差异有统计学意义（F>477，P = 0）。 结论严重牙颌面畸形如反 、深覆盖是导致曲面体层片的切牙影像失真的主要原因之一。     

口腔医学专业本科毕业生就业现状的调查分析和教育思考

目的研究口腔医学专业的教学如何面向市场,推出令用人单位满意的人才。方法采用问卷调查的方法对浙江省内有代表性的19家包含口腔医疗服务单位进行了调查,同时进行大学生就业心态调查问卷调查。结果医学生的就业心态出现多元化;毕业生不再一味追求高学历,更多的人选择了先就业后进修的道路。大多数用人单位着眼于提高医务人员的服务水平和质量,对毕业生的综合素质有了更高的要求。结论学校要尽力拓宽毕学生的就业渠道,提供更多的就业信息,树立面向基层的观念。     

Experimental evidence of formation of imines in the course of reduction of hydrazones

The reduction of hydrazones is generally suggested to proceed through a reductive cleavage of the nitrogen–nitrogen bond followed by a reduction of the carbon–nitrogen bond. This sequence of reduction processes is here supported for fluorenone (V) and benzophenone (VI) hydrazones as well as by a comparison of the reduction of fluorenone and benzophenone hydrazonium ions (I,III) with corresponding imines (II,IV). Another proof of the presence of imines as intermediates is the splitting of four-electron waves of hydrazones V and VI and hydrazonium ions I and VIII into two waves at pH < 2. This has been interpreted as due to differences in slopes dE_1/2/dpH and pK_a-values of protonated hydrazine derivatives on one side and corresponding imines on the other. In this pH-range imines formed in reductions of VI and VIII are reduced in a single two-electron wave, those of I and V in two one-electron steps. Fluorenone imine (II) is sufficiently stable to allow recording of time-independent current–voltage curves between pH 6 and 11. In this pH-range the imine (II) is reduced in two one-electron steps. Benzophenone imine (IV) has been found stable between pH 4.6 and 12. At pH 4.6–8 the reduction of the imine IV takes place in a single two-electron step, at pH 8–12 in two one-electron steps. Final proof of the initial cleavage of the N–N bond is presented by comparison with the reduction of nitrones.     

正常青年Monson球面半径的测量研究

目的测量正常青年Monson球面半径。方法选择60名(男30名,女30名)正常青年制取全口印模,应用立体摄影成像的原理与方法对Monson球面半径进行测量和统计学处理。结果Monson球面的半径平均为10.173 cm,大于理论值10.160 cm,差异有显著性(P<0.01);男、女性球面半径差异无显著性。结论本实验所得到的数据可作为全口义齿修复中记录颌位关系的一个参量。