超声根管预备对C形根管治疗的临床疗效观察

目的观察超声根管预备在C形根管治疗中的临床疗效。方法将178颗患牙随机分为2组,分别用手用K锉行逐步后退法根管预备和超声锉根管预备,冷侧压充填根管2年后观察其疗效。结果超声组明显优于手用K锉组。结论超声在根管预备方面有良好的疗效,应用于C形根管等复杂根管的治疗,省力、质量好。     

声波器械辅助镍钛根管器械预备老年人下颌第二磨牙C形根管的观察

目的：观察声波器械辅助镍钛根管器械预备老年人下颌第二磨牙C形根管的临床效果。方法：对133例老年人的140颗具有C形根管,诊断为慢性根尖周炎的下颌第二磨牙,随机分为二组：实验组,68颗,采用MM1500声波手机及其配套的Rispisonic锉针辅助镍钛旋转器械Hero642系统预备根管,对照组,72颗,镍钛旋转器械Hero642系统预备根管。两组均用氢氧化钙糊剂根管封药消毒后侧方加压法完成根管充填。对二组的根管预备并发症、根管治疗期间疼痛反应、根管充填质量进行比较。结果：实验组较对照组的疼痛反应轻且少,根管充填质量好于对照组,对照组根管预备并发症的总数相对较多。结论：声波器械辅助镍钛根管器械预备老年人慢性根尖周炎的下颌第二磨牙C形根管,可减轻减少疼痛反应,减少预备并发症,提高根管充填质量,具有临床应用价值。     

下颌第二磨牙C形根管预备方法的临床探讨

目的 探索预备下颌第二磨牙C形根管的有效方法.方法 对下颌第二磨牙C形根管初诊或根管再治疗的患牙,采用"拉网法"进行根管预备,完成根管充填后拍X线片检查充填效果.结果 C形根管的峡区被充分预备和成形,根充后峡区有均匀稀薄的X线阻射影像.结论 该根管预备方法能有效地预备C形根管的峡区,且不易发生根管侧穿.     

不锈钢K锉和镍钛K锉预备弯曲根管效果的比较研究

目的：比较手动不锈钢K锉与手动镍钛K锉预备弯曲根管的能力。方法：选取40个下颌磨牙近中颊侧弯曲根管，随机分为两组，每组20个根管。分别采用手动不锈钢K锉与手动镍钛K锉预备。采用双曝光技术比较两种器械预备弯曲根管后的根管偏移发生率。结果：两组根管偏移发生率存在显著性差异。结论：手动镍钛K锉能较好的维持根管原有形态。     

根管显微镜下下颌磨牙C形根管的临床分型与治疗

目的:探讨显微根管治疗技术对下颌磨牙C形根管系统的临床诊治疗效.方法:选择临床上需行根管治疗术且为C形根管的下颌磨牙79例,机用镍钛根管锉冠向下法预备主根管,显微镜下使用超声与K锉双敞法预备峡区,热牙胶垂直加压充填根管.记录根管分型、根管预备过程中并发症的情况,通过临床症状和体征、术前后X线片,半年随访X线片评价疗效.结果:C形根管系统中C1型较少见(12.66%);C2型发生率较高(62.02%),C2、C3型的近舌根管易超填(超填发生率:C2型4.08%;C3型15%).治疗过程中未发生器械折断、管壁侧穿等并发症,半年回访率为72.15%,随访病例中治疗成功率为91.3%.结论:C1、C2型具有较大的弧形带状根管,是临床治疗的难点;显微根管治疗术可以获得理想的疗效,值得临床推广使用.     

Protaper手动镍钛锉对老年人磨牙根管治疗期间急症发生率的影响

目的：评价ProTaper手动镍钛锉对老年人磨牙根管预备术后，根管治疗期间急症（EIAE）发生率的影响。方法：临床选取老年人磨牙108个，随机分为2组，分别采用ProTaper手动镍钛锉（实验组）和手动不锈钢K锉（对照组）进行根管预备，比较2组根管预备后，患牙EIAE发生的情况。结果：实验组在老年人磨牙根管预备后EIAE发生率为14．29％，对照组为32．69％，2组间差异有显著性（P〈0．05）。结论：应用ProTaper手动镍钛锉预备老年人磨牙根管，能够显著降低EIAE的发生。     

EDTA凝胶在钙化根管预备中的应用

目的：观察EDTA凝胶辅助K型锉和ProTaper手用镍钛锉在钙化阻塞根管预备中的临床效果。方法：选取根管细小钙化患牙68颗158个根管,随机分为两组,实验组EDTA凝胶辅助K型锉和ProTaper手用镍钛锉预备根管82个,对照组K型锉加ProTaper手用镍钛锉预备根管76个,根据临床检查和X线片比较两组根管预备效果。结果：实验组82个钙化根管有72个根管扩通,达到根管预备要求,成功率87．80％。对照组76个钙化根管有17个根管扩通,成功率22．37％,两者之间有显著差异。结论：EDTA凝胶辅助机械预备钙化根管可提高根管疏通率。     

不同器械根管预备效果的实验研究

目的：比较临床常用扩锉器械的根管清理效果。方法：将60个离体牙随机分为6组，分别为空白对照组、K型钻组、K型钻和锉组、K型钻和H型锉组、K型锉组和超声扩锉组，采用逐步后退法预备根管。扫描电镜观察根管内壁。结果：根管壁碎屑面积比较，K型锉组＞K型钻组＞K型钻和锉组＞空白对照组＞K型钻和H型锉组＞超声扩锉组，且前3组与其余各组之间具有显著性差异（P＜0．05），而后3者之间无显著性差异（P＞0．05）。结论：超声扩锉与K型钻和H型锉效果最好；K型钻与K型锉交替使用次之；单纯扩或锉不能有效进行根管清理。建议临床采用K型钻和H型锉交替预备根管。     

下颌第二磨牙C形根管的特点和临床治疗

目的探讨下颌第二磨牙C形根管的发生率、临床诊断和治疗方法。方法通过对152例下颌第二磨牙拍摄术前X线片和术中根管探查,按照Melton标准诊断C形根管;采用机用镍钛器械Hero642进行根管预备,次氯酸钠超声冲洗,热牙胶垂直加压技术充填根管。记录C形根管的发生率及临床特点,根据治疗前、中、后的X线片评价根管预备和充填的效果。结果下颌第二磨牙C形根管的发生率为32.2%,79.6%的C形根管患牙X线片表现为锥形融合牙根,20.4%表现为近、远中独立牙根;所有患牙均无根管内并发症发生,治疗效果好。结论下颌第二磨牙C形根管主要存在于融合牙根,根管探查结合X线片可诊断C形根管;机用镍钛器械预备根管、次氯酸钠超声冲洗和垂直加压技术充填根管可获得良好的治疗效果。     

三种方法预备下颌第二磨牙C形根管成形效果的比较

目的 评价3种常用根管预备方法对C形根管的成形效果,为临床治疗提供参考.方法 对临床拔除的具有C形根管的下颌第二恒磨牙60颗,应用改良Bramante技术,于距根尖2mm、5 mm和8mm处将牙根横断.选择手用不锈钢K锉逐步后退技术(Step-Back组)、逐步深入技术(Step-Down组)和机用旋转镍钛锉ProTaperTM系列冠向下预备技术(Crown-Down组)预备不同类型的C形根管,比较预备前后根管横截面形态的数码图像,对3种不同方法的成形效果进行评价.结果 3种方法预备离体下颌第二磨牙C形根管后均有遗漏.不锈钢K锉逐步后退技术和不锈钢K锉逐步深入技术分别在根冠部[遗漏面积百分比分别为(0.177±0.071)%、(0.068±0.074)%]和根尖部[遗漏面积百分比分别为(0.236±0.167)%、(0.295±0.171)%]遗漏较少(P＜0.05).CⅠ、CⅡ型遗漏出现在近远中多于颊舌侧,将其分为独立的2～3个根管预备可减少遗漏.不同方法预备根尖区的遗漏均显著高于根管中上部(P＜0.05).结论 早期开敞根管上段,将C形根管分为2～3个独立的根管进行预备,可以增进根管预备的成形效果.     

Variation in periodontal referral in 2 regions in theUK

This study investigated the periodontal referral patterns of general dental practitioners (GDPs) in Northern Ireland (NI) and North West England (NWE). A questionnaire dealing with periodontal referral was sent to all 520 GDPs registered in NI and to 274 GDPs in NWE. A usable return was made by 355 (68%) in NI and 189 (70%) in NWE. The NI dentists made significantly more periodontal referrals (median 5, range 0-80) in the year preceding the survey than those in NWE (median 2, range 0-50), p<0.001. Distance was the only factor significantly related to the referral rate in both regions with those who practised more than 25 miles from a specialist referring significantly fewer patients in both regions. In NI, there was a trend towards increased periodontal referral by GDPs who had attended more postgraduate courses; however, in NWE, this was not the case. The GDPs in NWE were significantly less likely than those in NI to refer patients with medical conditions. It is concluded that there is considerable variation in periodontal referral both within and between the 2 regions studied. It is further concluded that in many cases, non-disease factors, such as the accessibility of the specialist service, have powerful effects on the decisions made by dentists and patients in these regions (NI and NWE) in relation to periodontal referral. Much of the variance in referral in North West England, as in Northern Ireland, remains unexplained.     

云南省五岁儿童乳牙龋病调查分析

目的：了解云南省５岁儿童乳牙龋齿患病情况。方法：随机抽取云南省三个城市三个农村的２１３２名５岁常住儿童,采用第二次全国口腔健康流行病学调查标准调查龋齿患病情况。结果：云南省５岁儿童乳牙患龋率为７５．７５％,龋均为４．４４,充填率仅为６．５７％,仅占构成比的４．３９％。结论：云南省５岁儿童乳牙龋齿患病率高,充填率低。儿童龋病防治应注重两个方面：１．加强对家长和教师的幼儿口腔卫生保健知识及方法的宣传。     

Changes in cyclooxygenase metabolities in experimental periodontitis in Macaca mulatta

The four principal metabolites of cyclooxygenase (CO) were examined during the progression of experimental periodontitis in the rhesus monkey Macaca mulatta. Thirty-two monkeys were divided in four disease-matched groups. Three groups were treated with flurbiprofen, a potent CO inhibitor, at either 0.027, 0.27 or 7.1 mg/kg/day delivered systemically by a subcutaneously-implanted osmotic mini-pump. We have previously described the findings indicating that flurbiprofen treatment significantly retarded clinical attachment loss (ALOSS), redness and radiographic bone loss (BLOSS). This investigation focuses on the changes in CO metabolites which occur during disease progression of ligature-induced periodontitis and on the dose-response relationship of flurbiprofen, as it relates to disease inhibition and the suppression of ARA metabolites within the crevicular fluid (CF). In untreated animals there was a statistically significant 3-fold increase in CF levels of prostaglandin E2 (PGE2) and thromboxane B2 (TxB2) at 3 months, as compared to baseline, which positively correlated with increases in redness, bleeding, ALOSS and BLOSS. CF-PGE2 and TxB2 levels reached a 6-fold peak at 6 months and returned to baseline by 12 months. Flurbiprofen (Fb) prevented the 3-month rise in TxB2, but did not affect the increase in PGE2. At 6 months, Fb administration caused a dose-dependent inhibition of both PGE2 and TxB2. Probit analysis of the dose-response data revealed that the concentration of Fb which caused a 50% inhibition of CF-TxB2 level (the IC50 value for TxB2 synthesis) was approximately two logs lower than the IC50 value for PGE2 synthesis, i.e. TxA2-IC50 = 0.013 vs. PGE2-IC50 = 1.35 mg flurbiprofen/kg/d. The slopes of the PGE2 and TxB2 inhibition curves were identical, consistent with a similar mechanism or singular enzyme for the site of action of Fb inhibition of CO activity. However, the kinetics and sensitivity of Fb inhibition were significantly different for the CO activity responsible for TxB2 and PGE2 synthesis, perhaps due to different compartmentalization of CO within different cell types.     

Mast cells in masseter muscle in experimental bruxism in man

Three human subjects performed tooth grinding for 25 min, and after 20 h biopsies of the right and left masseter muscles were examined for their contents of mast cells. In comparison with specimens from a control group of three subjects, there was an increase of degranulating mast cells in muscles that had performed bruxism.