恒牙初期安氏Ⅱ^1错He不同骨面型颅底形态变化的头影测量分析

目的：探讨安氏Ⅱ^1错He不同骨面型的颅底形态特征。方法：选取恒牙初期的正常He和Ⅱ^1错He均角型、高角型、低角型的X线头颅侧位片各30张，男女各半，通过X线头影测量分析，比较Ⅱ^1错He3种骨面型和正常He的颅底形态变化。结果：Ⅱ^1错He3种骨面型均表现为颅基底角(Ba-SE-FMS)增大，高角组尤其表现在颅前基底角(FMS-SE-PM)增大，均角组、低角组颅中基底角(Ba-SE-PM)增加更为明显。Ⅱ^1错He颅底的有效垂直高度从低角组、均角组、高角组依次减小。结论：颅基底角可能更准确反映颅底的曲度，体现Ⅱ^1错He不同骨面型形成的机制。     

安氏Ⅱ1类错(牙合)不同骨面型的牙颌垂直向形态特征分析

目的：探讨安氏Ⅱ^1类错[牙合]不同骨面型牙颌垂直向形态特征。方法：选取恒牙初期的正常[牙合]Ⅱ^1类错[牙合]均角型、高角型、低角型的X线头颅侧位片各30张，男女各半，进行X线头影测量分析，通过多组间单因素方差分析及两两比较，明确Ⅱ^1类错[牙合]3种骨面型和正常[牙合]的牙颌垂直向形态变化。结果：（1）所有Ⅱ^1类错[牙合]总体上颌复合体的前部相对于后部垂直向发育过度。均角组上颌复合体整体相对发育过度，颅底-下颌支复合体发育不足：高角组上颌复合体前部发育过度，后部和颅底-下颌支复合体发育不足；均角组和高角组下颌有后下旋转的趋势。低角组颅底-下颌支复合体的垂直生长相对于上颌复合体的后部发育过度，上颌复合体前部发育正常。下颌有前上旋转的趋势。Ⅱ^1类错[牙合]L6的垂直高度降低，U6远中倾斜。高角组、均角组U6垂直高度未增加，功能[牙合]平面（FOP）前下倾斜．高角组U6及功能[牙合]平面倾斜的程度最大；低角组U6垂直高度降低，远中倾斜程度最小，功能[牙合]平面未见异常。结论：Ⅱ^1类错[牙合]不同骨面型牙颌形态表现出不同的垂直向特征，治疗时垂直向控制应采取不同的措施。     

恒牙初期安氏Ⅱ~1错不同骨面型颅底形态变化的头影测量分析

目的:探讨安氏Ⅱ1错牙合不同骨面型的颅底形态特征。方法:选取恒牙初期的正常牙合和Ⅱ1错牙合均角型、高角型、低角型的X线头颅侧位片各30张,男女各半,通过X线头影测量分析,比较Ⅱ1错牙合3种骨面型和正常牙合的颅底形态变化。结果:Ⅱ1错牙合3种骨面型均表现为颅基底角(Ba-SE-FMS)增大,高角组尤其表现在颅前基底角(FMS-SE-PM)增大,均角组、低角组颅中基底角(Ba-SE-PM)增加更为明显。Ⅱ1错牙合颅底的有效垂直高度从低角组、均角组、高角组依次减小。结论:颅基底角可能更准确反映颅底的曲度,体现Ⅱ1错牙合不同骨面型形成的机制。     

安氏Ⅱ~1类错不同骨面型的牙颌垂直向形态特征分析

目的:探讨安氏Ⅱ1类错牙合不同骨面型牙颌垂直向形态特征。方法:选取恒牙初期的正常牙合,Ⅱ1类错牙合均角型、高角型、低角型的X线头颅侧位片各30张,男女各半,进行X线头影测量分析,通过多组间单因素方差分析及两两比较,明确Ⅱ1类错牙合3种骨面型和正常牙合的牙颌垂直向形态变化。结果:(1)所有Ⅱ1类错牙合总体上颌复合体的前部相对于后部垂直向发育过度。均角组上颌复合体整体相对发育过度,颅底一下颌支复合体发育不足;高角组上颌复合体前部发育过度,后部和颅底-下颌支复合体发育不足;均角组和高角组下颌有后下旋转的趋势。低角组颅底一下颌支复合体的垂直生长相对于上颌复合体的后部发育过度,上颌复合体前部发育正常。下颌有前上旋转的趋势。(2)Ⅱ1类错牙合L6的垂直高度降低,U6远中倾斜。高角组、均角组U6垂直高度未增加,功能牙合平面(FOP)前下倾斜,高角组U6及功能牙合平面倾斜的程度最大;低角组U6垂直高度降低,远中倾斜程度最小,功能牙合平面未见异常。结论:Ⅱ1类错牙合不同骨面型牙颌形态表现出不同的垂直向特征,治疗时垂直向控制应采取不同的措施。     

恒牙初期安氏Ⅱ1错(牙合)不同骨面型颅底形态变化的头影测量分析

目的:探讨安氏Ⅱ1错(牙合)不同骨面型的颅底形态特征.方法:选取恒牙初期的正常(牙合)和Ⅱ1错(牙合)均角型、高角型、低角型的X线头颅侧位片各30张,男女各半,通过X线头影测量分析,比较Ⅱ1错(牙合)3种骨面型和正常(牙合)的颅底形态变化.结果:Ⅱ1错(牙合)3种骨面型均表现为颅基底角(Ba-SE-FMS)增大,高角组尤其表现在颅前基底角(FMS-SE-PM)增大,均角组、低角组颅中基底角(Ba-SE-PM)增加更为明显.Ⅱ1错(牙合)颅底的有效垂直高度从低角组、均角组、高角组依次减小.结论:颅基底角可能更准确反映颅底的曲度,体现Ⅱ1错(牙合)不同骨面型形成的机制.     

不同垂直骨面型安氏Ⅱ1类错(牙合)的软组织侧貌特征

目的：探讨安氏Ⅱ^1错（牙合）不同垂直骨面型患者软组织的侧貌特征。方法：随机选取安氏Ⅱ^1类错（牙合）低角型、均角型、高角型女性成年患者各28例，共84例，年龄18～23岁，平均20-3岁。选取矫治前X线头颅侧位片，进行头影测量，采用SPSS12．0统计软件包进行单因素方差分析和独立样本t检验。结果：一系列指标随着面高的增加呈现出有规律的变化趋势。侧貌突度及上、下唇突度依次明显增大，而面下部深度逐渐由过深变浅，同时上下唇弧的弧度由大变小、弧形由深变浅、由过于弯曲趋于过直立，尤其是低角组颏唇沟过凹陷而高角组过平坦。结论：垂直骨面型对安氏Ⅱ^1类错（牙合）的软组织侧貌特征尤其是唇颏部形态有着显著影响。     

Ⅰ类洞型设计的力学模型实验及二变量回归分析研究

目的 :对洞型设计中深度和宽度的关系进行研究 ,分析预备体抗力值的变化趋势。方法 :采用力学模型对设计洞型进行静态力学加载实验 ,并进行二变量回归分析研究。结果 :修复前 ,深度、宽度增加 ,都可使牙折的发生率增加 ,宽度为主要因素。修复后 ,随着修复体宽度增加 (即洞型宽度增加 ) ,载荷主要由修复体直接承担 ,咬合力通过修复体均匀传递到牙齿及牙周支持组织 ;修复体加大后 ,如载荷大部分直接作用在修复体上 ,可减轻了局部牙体组织承受的载荷。通过二元回归分析得出了回归方程和回归曲线。结论 :牙齿修复前后的折裂与洞型深度和宽度有关。通过二元回归分析得出洞型修复前后宽度、深度变化导致的预备体的抗力值变化趋势。回归方程为 :修复前 :Y =15 93 .3 17-5 1.178X1-79.489X2 　修复后 :Y =180 2 .92 8-192 .461X1 2 2 5 .12 8X2 。     

成人高低角骨面型横向颅面结构的比较研究

目的 比较成人高低角骨面型横向颅面结构的差异。方法 37例年龄在18～22岁之间的高低角骨面型成人为研究对象，拍摄后前位X线片，使用Winceph 8．0头影测量分析与图像数据管理系统，选取了29个测量项目进行头影测量分析。结果 高低角骨面型颅面宽度差别不大；低角骨面型牙弓较宽，高角骨面型牙弓较窄；面中部和髁突的开张程度低角骨面型较大；全面高、上面高和下面高与面宽之比高角骨面型大于低角骨面型。结论 成人高低角骨面型面部特征区别明显，高角骨面型面型窄长，低角骨面型面型短宽；面部的比例关系与线距的绝对值相比，能够更好地反映高低角骨面型的面部特征。     

高低角型男孩颅面部软组织侧貌水平向生长变化的纵向研究

目的：探讨高低角型男孩颅面部软组织侧貌在水平方向的生长变化。方法：根据Bjork前颅基底稳定结构重迭法,头影测量20名男孩在自然头势状态下9、12、15和18岁的X线头颅定位侧位片,然后,统计分析颅面部软组织侧貌Ga、N′、Nasal、Sn、A′、Ls、Li、B′、Pg及Gn各点至垂直平面(Pr-VER)的水平向距离变化以及上下唇至美学平面(E—line)的垂直距离变化。结果：1)高低角型男孩在9～18岁期间额部、鼻根部及唇部与鼻尖的水平距离随年龄增加而增加,而颏部与鼻尖水平距离虽有增加,但在某些阶段其距离反而缩短。2)高角型男孩Ga、N′、Nasal、Pg及Gn点到Pr水平距离其各阶段各测量值明显大于低角型,可唇部表现则不同,高角型唇部比低角型表现为更为前突。3)高角型颏部向前生长移动幅度小于低角型,而唇部向前生长幅度明显大于低角型。相对于美学平面,低角型上下唇在9～18岁期间后退幅度明显大于高角型。结论：高低角型男孩颅面部软组织侧貌生长变化存在显著差异,其主要区别在于唇部及颏部。这对正畸临床诊断与治疗具有借鉴作用。     

成人高低角骨面型颅面结构的比较研究

目的　比较成人高低角骨面型颅面硬组织结构的差异。方法　对37名成人样本(高角17例、低角 20例)的53项硬组织X线头影测量指标进行测量和比较分析。结果　颅部结构中,高角组蝶鞍角(N-S-Ar)和颅底角(N-S-Ba)明显小于低角组(P<0·01)。上颌结构中,两组间腭平面倾斜度(SN-PP,FH-PP)、上颌骨相对颅底的前后位置(S-Ptm)没有明显差异,高角组上颌骨体长度(Ptm-A)小于低角组,相对于颅骨和上颌骨的平面倾斜度(SN- OP,FH-OP,PP-OP)大于低角组,高角组下颌骨体长度(Go-Po)和升支倾斜度(FH-RP)的均值小于低角组,但未发现两组间有统计学差异,同时,下颌升支高度(Co-Go)、Po-NB距及下颌颏联合厚度(klhhd)明显小于低角组。下颌平面角 (SN-MP,FH-MP,PP-MP)、关节角(S-Ar-Go)、下颌角(Ar-Go-Me)、SUM及Y轴角大于低角组。两组间前上面高(N- ANS)没有明显差异;高角组前面高(N-Me)、后上面高(S-Co)、前下面高(ANS-Me)大于低角组,后面高(S-Go)小于低角组;同时面高指数(FHI,S-Go/N-Me)、前上面高与全面高比(N-ANS/N-Me)及前上面高与前下面高比(N-ANS/ANS- Me)均小于低角组,前下面高与全面高比(ANS-Me/N-Me)大于低角组。结论　成人高低角骨面型之间颅面结构存在较大差异,特别在面下1/3。     

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.     

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.     

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.     

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.     

颌骨动静脉畸形的栓塞治疗

目的：总结直接穿刺结合经血管内介入栓塞治疗颌骨动静脉静脉畸形的经验。方法：收治凳骨动静脉畸形患者6例,均进行了介入栓塞治疗。采用的栓塞材料为附凝血棉纤毛的螺圈,聚乙烯醇泡沫微粒和二氰基丙烯酸对丁酯。数字减影颈动脉造影在PHILIPSV300下完成。结果6例颌骨动静脉畸形患者中4,例急性出血得到了快速、有效控制,1例慢性渗血的右下 骨动静脉畸形患者,介入栓塞治疗,拔除松动的右下凳第一磨牙,有效地控制了出血,另1例伴局部软组织搏动性膨隆的上凳骨动静脉畸形患者,介入治疗后膨隆的搏动性得到明显改善,栓塞治疗后分别随访3－24个月,均未发现有口腔内渗血或出血。随访的X线片上,病灶区可见新骨形成。结论：局部穿刺结合经血管内介入栓塞治疗颌骨动静畸形是一种安全、有效的治疗方法。     

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。     

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.     

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。     

鼻测量法的进展

唇裂术后继发畸形是指唇裂修复术后,仍遗留或继发于手术操作和生长发育变化而表现出来的一类畸形[1]。包括唇畸形、鼻畸形和颌骨畸形。其修复较原发性唇裂修复更复杂,更灵活多变。而导致其修复复杂性的一个重要原因即是局部组织结构复杂变异和缺乏可靠的三维测量手段[2],鼻畸形     

口底癌34例临床分析

目的探讨口底癌的临床特性、治疗方法及预后。方法对我院自1992—2002年住院治疗的34例口底癌患者进行回顾性分析。结果34例口底癌患者中,男28例(82.4%),女6例(17.6%),男女比为4.7∶1,平均发病年龄58岁。发病部位:前口底22例(64.7%),后口底12例(35.3%)。淋巴结转移率41.2%。单纯手术组、化疗加手术组、放疗加手术组、化疗加手术加放疗组的5年生存率分别为45.5%、60.0%、50.0%、62.5%。结论口底癌以中老年患者好发,男性居多。易发生淋巴结转移,综合疗法疗效较好。