年轻恒前牙活髓切断术的临床疗效观察

目的 观察年轻恒前牙活髓切断术的临床疗效。方法 用活髓切断术治疗２０颗冠折露髓后３小时－１个月年轻恒前牙,术后追踪观察６个月－３年,结果 ２０颗年轻恒前牙有牙本质桥形成,牙根最终发育完成,其中仅１颗牙出现管腔钙化。结论 年轻恒牙活髓切断术适应证较宽,成功的关键在于掌握切髓的深度,使保留的牙髓正常,牙根发育程度及牙髓状况影响活髓切除术的疗效。     

儿童恒前牙切髓术后根髓组织学研究

目的：牙本质桥的形成是牙髓修复的特征，但至今人们对牙本质桥下方的牙髓组织是否健康仍有争议。本研究目的是观察儿童外伤冠折恒切牙切髓极后根髓的组织学特征，以证实牙髓修复后的牙髓组织变化状况。方法：对16例8－9岁儿童外伤冠折露髓的恒前牙行切髓术，氢氧化钙制剂覆盖牙髓断面，并在牙本质桥形成及根尖发育完成后不同时期行去髓术，将去除的根髓组织固定，常规组织学切片，显微镜观察。结果：术后12－24个月根尖发育完成，此时组织学观察可见牙本质桥下方的根髓组织无明显炎症。至36－48个月，牙髓组织逐渐出现退行性变，例如纤维性变和牙髓钙化等。结论：切髓术后2年内牙本质桥下方的根髓是正常的，而后牙髓逐渐出现退行性变，切髓术可作为儿童前牙冠折露髓的一种暂时治疗方法，当牙根发育完成时，则应采用去髓术。     

冠折恒前牙活髓切断术的临床疗效观察

年轻恒牙牙髓有很好的愈合潜力,保存活髓牙齿,使牙根继续发育并形成正常尖周组织十分有意义.本文对27个冠折恒前牙行活髓切断术,依据临床症状、牙本质桥形成、牙髓活力测试、根内和尖周病变以及牙根继续发育等标准评价,观察6个月至3年,绝大多数患牙有牙本质桥形成和牙根继续发育.     

年轻恒前牙冠折露髓活髓切断术的追踪观察

本研究对50例冠折恒前牙活髓切断术进行临床和X片观察。依据临床症状,牙髓电试反应,牙本质桥形成,根内和尖周病变以及牙根继续发育等标准评价。观察时间3～10年。长期观察结果表明,绝大多数患牙有硬组织桥形成和牙根继续发育,健康牙髓有很好的愈合潜力。然而,在牙根形成后2年可出现4种根内变化,其中管腔闭塞仅占4％。为避免管腔变化给修复带来的困难,选择适宜切髓部位和定期观察很重要。保存活髓牙齿,使牙根继续发育并形成正常尖周组织十分有意义。     

儿童恒前牙冠折后牙髓活力的保存方法

目的：探讨儿童恒前牙冠折后不同受损程度牙髓活力的保存方法。方法：采用三种方法对不同受损程度的72例98个冠折恒前牙牙髓进行处理，并定期复查。结果：对14个单纯性釉质折断牙牙髓随访2年，牙髓活力不受影响；对23个牙本质折断但未露髓患牙护髓后2年成功率为82.6%，对61个牙本质折断并露髓患牙采取活髓切断术，其2年成功率为81.9%。结论：对损伤程度不同的冠折牙牙髓应采取不同的治疗方法；活髓切除术不仅适用于年轻恒牙，对于牙根已形成但仍处于儿童暑期的恒前牙同样适用；牙本质桥的形成并不意味其下方的牙髓组织正常。     

年轻恒牙冠折临床处置技巧及疗效评估

目的：探讨年轻恒牙冠折的临床处理技巧及疗效。方法：对26例8～15岁患者32个年轻恒牙外伤冠折病例根据不同症状采取间接盖髓术、活髓切断术、根尖诱导术、根管治疗术等进行治疗,对治疗结果进行随访,观察术后1周、3周、6周、6个月的疗效。结果：术后1周观察,间接盖髓术组有1例,活髓切断术组有2例患牙发生自发性疼痛。术后6个月复查,间接盖髓术组成功7例,失败1例;活髓切断术组成功10例,失败2例;根尖诱导术组成功5例,失败2例;根管治疗术组成功5例,无失败病例。结论：对冠折未露髓的年轻恒牙应及时处理,防止细菌侵入造成牙髓感染;冠折露髓的年轻恒牙应根据患牙根尖发育情况采取活髓切断术、根尖诱导成形术、根管治疗术等不同的治疗方案,治疗完成后还应定期随访,如发现牙髓情况变化,要及时调整治疗方案,以利于牙齿的继续发育和后期修复。     

年轻恒前牙冠折露髓部分活髓切断术的疗效

目的研究年轻恒前牙冠折露髓部分活髓切断术的疗效。方法 120颗患牙中,有70颗采用部分活髓切断术,有50颗采用传统的活髓切断术,统计两组的成功率,并进行比较。结果部分活髓切断术和传统活髓切断术的成功率分别为91.7%和85.4%。结论部分活髓切断术是年轻恒牙冠折露髓一种理想的治疗方法,可以较长久的保存牙髓的活力,继续发挥其固有的功能,促进牙根的继续发育。     

活髓切断术治疗年轻恒前牙冠折露髓的疗效观察

在年轻恒牙外伤中,冠折露髓率高达33.98%[1]。此年龄段的恒前牙根尖大多未发育完成,因此,保存活髓,促进牙根的继续发育成为冠折露髓治疗的关键。作者对46个年轻恒前牙冠折露髓进行活髓切断术治疗与随访观察,现报道如下。     

儿童恒前牙冠折露髓切髓术的选择

儿童恒前牙外伤冠折露髓后的治疗，通常依据其牙髓外露程度、时间和牙根发育状态而采用盖髓术、切髓术或去髓术。盖髓术即在髓角外露处覆盖盖髓剂，并用即刻带环或树脂全冠维持盖髓剂，使髓角修复。切髓术即切除部分牙髓，于牙髓断面覆盖盖髓剂，保存根部牙髓活力，使牙根...     

Metapex糊剂用于年轻恒牙活髓切断术的临床研究

观察Metapex糊剂用于活髓切断术的临床疗效。方法：对因各种原因引起冠折露髓的年轻恒牙患者28例3l颗患牙行活髓切断术治疗,用Metapex糊剂作为活髓保存剂。术后对患牙进行定期随访观察。结果：26例患者29颗患牙均于1～3个月在x线片上观察到牙本质钙化桥的形成并持续增厚,牙根继续发育直至根尖孔闭合,整个过程约1．5～3．0年,无根内外吸收和根管钙化出现,成功率93．55％。结论：Metapex糊剂用于活髓切断术可取得较满意的疗效。     

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