非血管化游离骨移植同期种植骨活力的实验研究

目的观察非血管化骨移植同期种植的骨块在不同离体时间点植入体内后细胞活力及成骨情况.方法拔除狗前磨牙,口腔粘膜完全愈合后,截除长度3 cm的无牙下颌骨段,取不带血管和软组织的髂骨全层,植入直径2 mm带自攻螺纹的纯钛种植体2～3枚,分别在离体60、120分钟内植入下颌缺损区.术后4、8周取出植骨块,观察游离移植的非血管化骨块内细胞活力和新骨形成情况.结果非血管化游离骨移植同期种植恢复了下颌骨节段性缺损的连续性.游离骨块在离体60分钟植入体内4～8周为活骨块,可见到大量成活的骨细胞,并有数量不等的新骨形成.离体120分钟的游离骨块植入体内后4～8周为死骨块,其中未见成活骨细胞,部分骨块中见到破骨细胞.结论在以狗为对象的实验中,非血管化游离髂骨块移植同期种植可以修复长度3cm的下颌骨节段性缺损,植入体内骨块能否成活与其离体时间有关.     

离体时间对非血管化骨牙种植体骨结合影响的组织学观察

目的 :研究非血管化自体移植骨离体时间差异对非血管化骨 (Non VascularizedBoneGraft ,NVBG)牙种植体 (IMP)同期植入术中植骨块与种植体形成骨结合的影响。方法 :西安地区成年杂种狗 12只 ,随机分为 2组 ,分别拔除其一侧 4个前磨牙 ,6周后在下颌骨拔牙区制作长约 3cm中断性缺损 ,分别在NVBG离体后 40min以内和 80min以上行NVBG IMP同期植入术修复下颌骨缺损 ,术后 4周、12周、2 4周分别处死每组 2只动物 ,进行组织学观察。结果 :2 4周时 ,所有NVBG与种植体之间均形成了良好的骨结合 ;但 4周、12周时 ,NVBG离体时间在40min以内组新骨形成比离体时间在 80min以上组多 ,NVBG与种植体形成骨结合情况优于离体时间在 80min以上组。结论 :无论NVBG离体时间小于 40min还是大于 80min ,非血管化骨移植同期种植体植入最终均能形成良好的骨性结合 ,只是离体时间越长可能新骨形成和骨结合形成越慢     

非血管化游离骨移植中细胞活力的实验研究

目的 :探讨非血管化游离骨块中细胞存活能力及数量与离体时间的关系。方法 :取狗非血管化游离髂骨块 ,在离体 2 5～ 15 0min的不同时间点 ,消化骨块获得细胞 ,进行活细胞计数。对消化获得细胞体外培养2 4h后 ,再进行活细胞计数 ,分析细胞存活与离体时间的关系。结果 :在离体 2 5～ 15 0min时间内 ,骨块细胞的存活率从 91.96%降至 9.5 2 %。统计学检验 ,2 5min组与 70min以前组之间没有统计上的差别 ,P >0 .0 5 ;2 5min组与 70min及其以后组之间有明显差别 ,P <0 .0 1。培养 2 4h后 ,以上各时间点的细胞存活率则从88.73 %到 3 .88% ,组间差别与刚离体时相同 ,但 70min后的各组活细胞率明显下降。结论 :非血管化狗游离髂骨块的离体时间对其中的细胞存活有明显影响 ,离体 70min可能是其关键点 ;在非血管化游离骨移植中 ,尽量缩短骨块的离体时间 ,有利于保存更多的活细胞     

纯钛种植体与非血管化髂骨骨结合的组织学观察

目的：研究纯钛种植体和非血管化髂骨块的骨结合情况。方法：10只杂种犬被随机分成5组，分别切取两侧游离髂骨移植于对侧，移植骨内同时植入钛种植体，术后不同时间点取材，组织学观察。结果：3周时，移植骨以吸收和坏死为主，6周时有新骨形成，9周时新骨形成的数量增加，12周时移植的骨块成活，骨组织改建完成，植入的钛种植体和移植的髂骨块之间无软组织介入，标志种植体与移植骨之间骨结合完成。结论：在本实验条件下，钛种植体和非血管化髂骨块可以形成完全骨结合。     

高压氧影响游离植骨种植体骨整合的组织学研究

目的：探讨高压氧能否促进种植体在非血管化新鲜自体游离移植骨上形成骨整合。方法：选用４只杂种成年狗,随机分成２组,每组２只,在狗下颌骨下缘各截取４ｃｍ×１．５ｃｍ大小的方形骨块,完全游离后原位植入,在植骨块上种入２个ＨＡ种植体。实验组动物在术后第 ３天开始进行高压氧（ＨＢＯ）治疗（２４．２ ｋＰａ、１．５ｈ／ｄ、５ｄ／周,共 ４周）,术后１０周处死 ４只动物,取含种植体的骨块,脱钙后腊包埋、切片、ＨＥ染色、组织学观察。结果：ＨＢＯ组种植体在移植骨上形成骨整合,种植体周围的新骨呈连续的骨界面。非ＨＢＯ组种植体界面呈不连续的新骨界面。结论：羟基磷灰石涂层种植体可在非血管化自体游离移植骨上形成骨整合,ＨＢＯ可以促进骨结合的形成。     

受区骨膜对非血管化骨移植种植体与骨结合的作用

目的 探讨受区骨膜对非血管化骨移植种植体与骨结合的影响,为临床在非血管化骨移植 同期进行种植体植入提供依据。方法 在狗的双侧下颌骨下缘切取1.2cm×4.0cm大小的骨块原位再植,将 钛芯羟基磷灰石涂层(Ti-HA)圆柱形种植体植入移植骨块中,左侧去除骨膜为实验组,右侧为对照组。分 别于术后2周,1个月,2个月,4个月,6个月处死动物取材,进行X线摄片,组织学切片及扫描电镜观察。 结果 在各个时间点上,实验组和对照组的骨愈合情况及植种植体与骨结合情况相似无明显差异。结论 受区骨膜的存在与否对非血管化骨移植后骨的愈合及种植体与骨的结合无明显的影响。     

正畸微种植体植入早期骨改建中破骨细胞的观察

目的：观察微种植体植入早期破骨细胞的产生,探讨破骨细胞变化与骨改建的关系。方法：雄性新西兰兔20只随机分为4组,在胫骨近心端近骺板处植入微种植体1颗,分别于植入3、7、14、28 d后处死(每组5只)。HE染色观察微种植体周围骨组织的形态学变化,抗酒石酸酸性磷酸酶(TRAP)染色标记破骨细胞并作半定量分析。采用SPSS19.0软件包对数据进行统计学分析。结果：微种植体植入3 d后,种植体骨接触区可见大量红细胞、炎症细胞、间叶细胞和骨碎屑,无明显破骨细胞。7 d后,编织骨新生,呈颗粒状,破骨细胞位于骨陷窝中。14 d时,大量新生的编织骨呈网格状,破骨细胞增多,骨改建明显。28 d时,编织骨成片状,与层状骨相连,破骨细胞数目减少。TRAP染色半定量分析显示,破骨细胞数目在14 d时达到高峰,各时间点间均有显著差异(P<0.01)。结论：在正畸微种植体植入早期破骨细胞产生,在新骨生成的活跃阶段破骨细胞数目增多,提示破骨细胞参与微种植体周的骨改建过程。     

VEGF和TGF-β1促进非血管化骨移植同期种植骨结合的实验研究

目的:探讨外源性VEGF和TGF-β1对非血管化骨移植同期种植的影响。方法:选用实验犬24只(术前1个月拔除双侧下颌前磨牙),随机分为A、B 2组。选取左侧下颌骨造成2.5 cm全层骨缺损,植入同样大小的全层自体髂骨,钛板固定(髂骨块离体时间控制在20 min以内)。A组(12只)移植髂骨块内植入1枚钛种植体。B组(12只)将钛种植体与rhVEGF165和rhTGF-β1复合后再同法植入移植髂骨内。在所有实验犬的右侧下颌无牙区植入1枚种植体作为对照。术后1、2、4个月取材,行X线、组织学、显微CT观察和种植体骨结合力测试。结果:术后1、2个月B组种植体骨接触率较A组显著增高;对种植体周围骨小梁的显微CT分析表明,B组的成骨的作用较A组明显增强。术后4个月,A、B 2组BIC达到60%以上,种植体骨界面结合力接近220 N,已形成较好的骨结合。结论:VEGF和TGF-β1对NVBG同期种植体骨结合早期(术后1～2个月)有明显的促进作用。NVBG同期种植体在术后4个月可以进行上部义齿修复。     

血管化和非血管化骨移植种植体与骨结合的比较研究

本研究对骨结合式牙根种植体在血管化和非血管化骨移植中与骨结合过程进行了组织形态学观察和界面结合强度测试。结果表明:种植体在血管化骨移植中与骨的结合和与正常骨的结合相同。非血管化骨移植尽管发生“爬行替代”,但种植体仍能在种植后60天起,随着死骨的吸收,同长入的新骨产生有效的骨结合。种植后30天和60天,血管化骨移植的种植体—骨结合强度比非血管化骨移植的高,但到种植后90天和180天,两者强度相等,提示临床用非血管化骨移植修复下颌骨缺损的同时,可植入种植体以行功能性整复,但在进行上部结构修复的时间上,要比血管化骨移植适当延长。     

钛种植体—骨移植早期修复火器性下颌骨缺损的初步实验研究

从早期功能重建的角度出发,对钛种植体在血管化骨移植早期修复火器性下颌骨缺损中的应用进行了研究.初步结果表明:钛种植体应用于血管化骨移植早期修复火器性下颌骨缺损是可行的;钛种植体与血管化移植骨星骨性结合界面;游离骨移植不宜一期植入种植体。     

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.     

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     

下颌角骨折治疗后并发症的临床分析

目的研究下颌角骨折治疗后并发症,分析原因并提出预防方法。方法回顾分析我院206例下颌角骨折患者的治疗及并发症情况,分颌间固定组62例,内固定组120例,颅颌绷带组24例。结果治疗后发生的并发症有骨感染4例,医源性损伤2例,牙合干扰3例,错牙合畸形2例,颞下颌关节功能紊乱病2例。结论下颌角骨折的治疗应首选坚强内固定,应选择正确的手术方案,加强术前、术后抗感染治疗及术后肌功能训练,对骨折线上的阻生齿应尽可能保留,以减少并发症。     

过量氟对鼠牙釉质发育的影响

为了探讨过量氟对鼠牙釉质发育的影响，本研究以大白鼠为实验动物，观察氟中毒后鼠牙造袖器、造釉细胞和釉质的组织形态学变化，并利用生化方法，检测氟中毒后釉质分泌期和成熟期釉质蛋白含量的变化。结果显示分泌期造釉细胞有空泡形成，釉基质钙化不均。分泌期釉质蛋白含量来见明显改变（P＞005）。成熟期釉质蛋白含量增加（P＜0.01）。表明氟中毒对鼠牙釉质造釉细胞形成过程可产生损害性影响。