带环式Herbst矫治器的支抗改良及应用比较

目的　针对传统带环支抗式Herbst矫治器使用中带环易断裂的原因 ,提出改良设计 ,比较传统和改良支抗设计治疗中带环断裂情况。方法　记录 6例传统支抗设计 ,7例改良支抗设计患者矫治过程中带环断裂情况。结果　传统支抗的Herbst矫治器 ,上颌磨牙和下颌第一双尖牙的带环最易受损 ,尤以下颌第一双尖牙为甚。增加颊侧连接丝后的改良支抗 ,带环断裂情况明显改善。结论　改良带环支抗设计制作简单 ,临床效果满意     

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目的    探讨改良式Herbst 矫治器矫治安氏Ⅱ类下颌后缩伴上牙弓狭窄患者的临床疗效。方法    2004—2009年在南昌大学口腔医院正畸科采用改良式Herbst矫治器治疗11例安氏Ⅱ类下颌后缩伴上牙弓狭窄患者,通过矫治前后头影片的测量对比,分析该矫治器的疗效。结果    经改良式Herbst矫治器治疗6～8个月后,11例患者的下颌均明显前移,上下牙弓协调,下颌后缩面型显著改善。结论    改良式Herbst矫治器能有效地矫治安氏Ⅱ类下颌后缩伴上牙弓狭窄的患者。     

下颌前伸矫治器和Herbst矫治器治疗AngleⅡ类错的对比研究

目的 :比较下颌前伸矫治器 (MandibularProtractionAppliance ,MPA)和Herbst矫治器对AngleⅡ类错牙合的治疗效果。方法 :选择 2 6例AngleⅡ类错牙合病人 ,男 14例 ,女 12例 ,最大 13岁 ,最小 10岁。X线头影测量显示主要为下颌后缩及轻微上颌前突 ,手腕片显示为生长发育高峰期。将这些病人分成两组 ,一组用下颌前伸矫治器治疗 (MPA组 ) ,另一组用Herbst矫治器进行治疗 (HA组 )。功能矫治结束时 ,两组病例均摄X线头颅定位侧位片 ,由专人定点、测量 ,并进行统计学分析。结果 :X线头影测量结果显示两组病例中Co -Pg、Go -Pg及Co -Go均增大 ,其变化量经统计学检验差异无显著性意义 ,表明下颌前伸矫治器及Herbst矫治器均能促进下颌骨生长 ,尤其是下颌升支的生长 ;SNB、ANB、U1-L1、U1-NL及L1-MP的变化量经过统计学检验差异有显著性意义 ,说明下颌前伸矫治器和Herbst矫治器都能有效矫治AngleⅡ类错牙合颌骨矢状关系不调 ,尤其是前者更有效 ,而Herbst矫治器易引起支抗丢失 ,即易使上颌前牙舌向倾斜、下颌前牙唇倾。结论 :下颌前伸矫治器和Herbst矫治器治疗早期AngleⅡ类错牙合均可取得明显的骨胳改变 ,但前者治疗效果更好     

下颌前伸矫治器和Herbst矫治器治疗Angle Ⅱ类错牙合的对比研究

目的:比较下颌前伸矫治器(Mandibular Protraction Appliance,MPA)和Herbst矫治器对Angle Ⅱ类错牙合的治疗效果.方法:选择26例Angle Ⅱ类错牙合病人,男14例,女12例,最大13岁,最小10岁.X线头影测量显示主要为下颌后缩及轻微上颌前突,手腕片显示为生长发育高峰期.将这些病人分成两组,一组用下颌前伸矫治器治疗(MPA组),另一组用Herbst矫治器进行治疗(HA组).功能矫治结束时,两组病例均摄X线头颅定位侧位片,由专人定点、测量,并进行统计学分析.结果:X线头影测量结果显示两组病例中Co-Pg、Go-Pg及Co-Go均增大,其变化量经统计学检验差异无显著性意义,表明下颌前伸矫治器及Herbst矫治器均能促进下颌骨生长,尤其是下颌升支的生长;SNB、ANB、U1-L1、U1-NL及L1-MP的变化量经过统计学检验差异有显著性意义,说明下颌前伸矫治器和Herbst矫治器都能有效矫治Angle Ⅱ类错牙合颌骨矢状关系不调,尤其是前者更有效,而Herbst矫治器易引起支抗丢失,即易使上颌前牙舌向倾斜、下颌前牙唇倾.结论:下颌前伸矫治器和Herbst矫治器治疗早期Angle Ⅱ类错牙合均可取得明显的骨胳改变,但前者治疗效果更好.     

铸造技术在Herbst矫治器支抗部分的应用

Ｈｅｒｂｓｔ矫治器是美国正畸治疗中矫治Ａｎｇｌｅ’ｓⅡ类错的一种固定功能矫治器。它与其他功能矫治器的区别在于患者自己不能随意摘下矫治器 ,因而可以使下颌前移保持连续性 ,在行使咀嚼功能时也能发挥前移下颌的作用。目前国内已在一定范围应用 ,但常规Ｈｅｒｂｓｔ支抗部分有一定不足 :带环强度不够 ;支抗易丧失。我们采用铸造技术完成支抗部分 ,以克服Ｈｅｒｂｓｔ矫治器在临床应用中的缺陷。经临床应用效果满意 ,现介绍如下 :铸造预备 :首先将分牙圈置于第一双尖牙近中与第一恒磨牙远中 ,牙分好后取出分牙圈 ;然后取模、灌注人造…     

下颌前伸矫治器和Herbst矫治器治疗AngleⅡ类错He的对比研究

目的：比较下颌前伸矫治器(Mandibular Protraction Appliance，MPA)和Herbst矫治器对AngleⅡ类错He的治疗效果。方法：选择26例AngleⅡ类错He病人，男14例，女12例，最大13岁，最小10岁。X线头影测量显示主要为下颌后缩及轻微上颌前突，手腕片显示为生长发育高峰期。将这些病人分成两组，一组用下颌前伸矫治器治疗(MPA组)，另一组用Herbst矫治器进行治疗(HA组)。功能矫治结束时，两组病例均摄X线头颅定位侧位片，由专人定点、测量，并进行统计学分析。结果：X线头影测量结果显示两组病例中Co—Pg、Go—Pg及Co—Go均增大，其变化量经统计学检验差异无显著性意义，表明下颌前伸矫治器及Herbst矫治器均能促进下颌骨生长，尤其是下颌升支的生长；SNB、ANB、U1—L1、U1—NL及L1—MP的变化量经过统计学检验差异有显著性意义，说明下颌前伸矫治器和Herbst矫治器都能有效矫治AngleⅡ类错He颌骨矢状关系不调，尤其是前者更有效，而Herbst矫治器易引起支抗丢失，即易使上颌前牙舌向倾斜、下颌前牙唇倾。结论：下颌前伸矫治器和Herbst矫治器治疗早期AngleⅡ类错He均可取得明显的骨胳改变，但前者治疗效果更好。     

Herbst双期拔牙矫治对颞下颌关节位置影响的CBCT研究

目的:探讨Herbst双期拔牙矫治对颞下颌关节位置关系的影响.方法:纳入15例恒牙列早期安氏Ⅱ类错(牙合)下颌后缩患者,一期矫治采用Herbst矫治器,然后拔除每位患者的4个前磨牙;二期矫治采用edgewise固定矫治器.在Herbst矫治器矫治前两周(T1期)、Herbst矫治器初戴入矫治时(T2期)、Herbst矫治器拆除时(T3期)及二期固定矫治器拆除时(T4期)分别拍摄锥形束CT(cone beam computed tomography,CBCT).应用InvivoDental软件对CBCT图像进行三维重建,再对颞下颌关节间隙进行测量,并进行统计分析.结果:T1-T2-T3期,关节前间隙先减小后增大,关节上间隙、关节后间隙先增大后减小;T3-T4期,关节上、后间隙进一步减小,关节前间隙无明显变化;与T1期比,T4各关节间隙的变化均无明显差异.结论:髁突在关节窝中的位置在Herbst矫治开始时向前下移位,一期功能矫治结束时尤其双期矫治结束时几乎回到了治疗前的位置.     

Herbst矫治器与头帽肌激动器矫治骨性安氏Ⅱ类错的比较研究

目的对比研究头帽Activator与Herbst矫治器治疗骨性安氏Ⅱ类错的机理.方法应用Pancherz设计的Herbst矫治器及Van beek设计的Activator治疗Ⅱ类错 ,以X线头影测量方法评价疗效.结果头帽Activator对上颌生长抑制作用强于Herbst矫治器,而Herbst矫治器刺激下颌生长尤其是水平向生长效果优于头帽Activator;头帽Activator内收压入上前牙效果显著;而Herbst矫治器压低下前牙较为明显.结论头帽Activator更适于矫治上颌矢状及垂直向发育过度的Ⅱ类错 ,Herbst矫治器适于矫治下颌发育不足的Ⅱ类错 .     

Herbst双期拔牙矫治对颞下颌关节骨性结构影响的锥形束CT研究

目的 应用锥形束CT（CBCT）研究Herbst双期拔牙矫治对颞下颌关节骨性结构的影响。方法选取15例以下颌后缩为主要临床表现的恒牙列早期安氏Ⅱ类错牙合患者,采用Herbst双期拔牙矫治,在Herbst矫治器矫治前两周（T1期）、Herbst矫治器初戴入矫治时（T2期）、Herbst矫治器拆除时（T3期）及二期固定矫治器拆除时（T4期）时进行CBCT扫描,应用InvivoDental软件对CBCT图像进行三维重建和相关测量。结果1）14例患者（28侧颞下颌关节）在T3期出现髁突后上区外侧边缘高密度、内部区域低密度类似“新月形”的增生影像。2）T3-T2期、T4-T1期,髁突前后径平均增加了0.62、0.66mm（P<0.01）;髁突头高度平均增加了0.54、0.53mm（P<0.01）。结论Herbst功能矫治器能促进髁突发生生长改建。     

Herbst矫治器与头帽肌激动器矫治骨性安氏Ⅱ类错He的比较研究

目的对比研究头帽Activator与Herbst矫治器治疗骨性安氏Ⅱ类错的机理.方法应用Pancherz设计的Herbst矫治器及Vanbeek设计的Activator治疗Ⅱ类错,以X线头影测量方法评价疗效.结果头帽Activator对上颌生长抑制作用强于Herbst矫治器,而Herbst矫治器刺激下颌生长尤其是水平向生长效果优于头帽Activator;头帽Activator内收压入上前牙效果显著;而Herbst矫治器压低下前牙较为明显.结论头帽Activator更适于矫治上颌矢状及垂直向发育过度的Ⅱ类错,Herbst矫治器适于矫治下颌发育不足的Ⅱ类错.     

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.     

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.     

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。     

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