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J. König A. Rühling H. Schlemme T. Kocher C. Schwahn H. C. Plagmann 《European journal of dental education》2002,6(4):169-175
The influence of systematic dummy-head training with Periopolishe (PP, group A) and Gracey instruments (GRA, group B) on the effectiveness of root debridement was evaluated by Rühling et al., 2002 (9). Their results indicate that independent of the instrument used, untrained operators were only able to debride root surfaces at low levels of effectiveness. It was possible to increase effectiveness to a high level through systematic training in both groups. The aim of the present study was to assess the role of operator motivation and self-assessment on scaling effectiveness. Before baseline, operators were asked to answer a questionnaire rating the expectation of the instrument performance. Four groups of inexperienced operators (n = 11 each) received 10 weeks dummy-head training. In groups A (GRA) and B (PP), training was combined with a motivational programme. Groups C (GRA) and D (PP) received the same training, but no additional motivational programme. In a dummy-head, 10 test teeth were debrided and operators were asked to estimate their effectiveness of debridement at each test day. Effectiveness was calculated as percentage of debrided root area on 10 test teeth at different time points with an image analysis programme (NIH Image) and ANOVA. Two groups were compared using the Mann-Whitney U-test (unpaired) and the Wilcoxon signed ranks test (paired). Motivated groups (A and B) reached about 25% higher debridement results (p < 0.001) and were able to estimate their effectiveness more precisely compared to groups C and D. In the low motivation groups (C and D), overestimation of more than 20% was evident (p < 0.001). The questionnaires revealed underestimation of the GRA instruments and overestimation of PP instruments. Operator motivation and self-assessment greatly influence learning of effective root debridement. 相似文献
64.
Relationship between the gastric myoelectric and mechanical activity in the genesis of ulcers in indomethacin-insulin-treated rats 总被引:2,自引:0,他引:2
We have proposed that gastric contractile activity mechanically induces ulcers in the nonsteroid antiinflammatory drug (NSAID)-treated rat. This study examines first the relationship between number (dose) of peristaltic contractions applied to the mucosa and the ulcer score. Second, it examines the relative roles of: altered gastric myoelectrical activity (MEA) resulting from indomethacin (Indo) pretreatment, insulin-induced gastric peristalsis, and a combination of the two in the generation of mucosal lesions. Third, it examines the effect of exogenous prostaglandin on the Indo-altered MEA and relates it to ulcerogenesis. Indo pretreatment increased gastric tone and MEA. In such animals, the dose of peristaltic contractions applied to the gastric wall was related to the ulcer score in a dose-dependent manner. Exogenous prostaglandin (PG) reversed the MEA effect of Indo and reduced ulceration. It is postulated that an altered smooth muscle state secondary to inhibition of prostaglandin synthesis (PG-S) renders the mucosa vulnerable to injury by peristaltic action.This study was supported by the Fast Foundation. 相似文献
65.
G. Bassotti F. Sietchiping Nzepa G. de Roberto M. J. Fischer A. Morelli 《Digestive and liver disease》2004,36(1):78-81
Selective serotonin reuptake inhibitors are frequently employed to treat depression. However, although rarely, coagulation abnormalities have been described following the use of these compounds, and these effects appear to be enhanced by simultaneous use of nonsteroidal anti-inflammatory drugs. We describe a case of reversible symptomatic duodenal compression caused by a retroperitoneal hematoma after ingestion of sertraline and nimesulide. 相似文献
66.
神经根慢性嵌压损伤的动物模型建立 总被引:3,自引:0,他引:3
目的:建立一种由自身骨性增生造成神经根慢性嵌压损伤的动物模型,为相关实验提供造模方法一方法:30只健康家猫,手术显露右侧C7、C8和L5、L6冲经根及其椎问孔内口,用牙髓钻破坏椎间孔周围骨皮质后,将“V”形松质骨块沿骨壁嵌于神经根通道的骨性管道内及侧隐窝后方,左侧做正常对照。在造模术前和术后第2、4、8、12、24周行磁刺激运动诱发电位(MEP)检测,每次随机选6只,4~5只行影像学检查,以确定神经根通道的狭窄程度和神经根受压状态,6只均做病理组织学检查和椎间孔截面积测量。结果:术后早期实验侧肢体出现行为异常:而后有不同程度肌萎缩;后期部分肢体远端出现溃疡。影像学检查随着嵌压时间延长.实验侧椎间孔骨痂增多,狭窄加重。神经根受压变形,椎间孔骨性截面积8周后明显减小,与对照侧比较有显著性差异。术后2周,神经根组织学检查主要表现为神经束膜、内膜的水肿。髓鞘肿胀;4周后发生节段性脱髓鞘:8周时神经轴突增粗、断裂,远端瓦勒氏变性;12周后变性冲经结构崩解、吸收,形成空洞:24周时整个神经干纤维化。术后4周时实验侧MEP开始出现潜伏期延长;8周时伴有波形分化不清;12周波幅明显下降:24周MEP的引出困难,部分电位消失。结论:采用椎问孔内自体松质骨植入,造成神经根慢性嵌压性损伤模型成功率高,操作简单,适用于脊柱各个节段,其损伤部位和形式与临床更为接近。 相似文献
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68.
压迫及非压迫因素在实验性神经根性疼痛中的作用 总被引:6,自引:0,他引:6
目的:探讨压迫及非压迫因素在实验性椎间盘源性神经根性疼痛中的作用。方法:取大鼠白体脊椎关节突修剪后放置在L5神经根下.造成对L5神经根的直接压迫(压迫组);取大鼠白体尾椎椎间盘组织无压迫下放置在L5神经根表面(非压迫组):同时设立对照组。术后不同时间点测定各组大鼠后足底机械刺激疼痛阈值的变化。结果:压迫组与非压迫组大鼠后足底均产生了一个长时程机械刺激疼痛阈值的降低;与压迫组相比.非压迫组大鼠术后1天就开始出现了疼痛阈值降低(P〈0.05),明显早于压迫组大鼠,并且疼痛阈值降低更加显著:而压迫组大鼠术后1周时才出现明显的疼痛阈值降低(P〈0.05)。对照组大鼠疼痛阈值没有发生明显的改变。结论:尽管压迫和非压迫因素都参与椎间盘源性神经根性疼痛的发生.但二者作用的时间不同+在椎间盘突出的早期阶段非压迫因素可能在疼痛中起着重要的作用:随后压迫因素可能逐渐成为致痛的主因。 相似文献
69.
The antimicrobial effects of a saturated calcium hydroxide solution, and in combination with 10% and 20% detergent, were evaluated on Streptococcus faecalis. Strepto-coccus sanguis, Streptococcus mutans, Streptococcus salivarius, Neisseria sp., diphlheroid, Staphylococcus aureus, Lactobacillus sp., Staphylococcus epidermidis, Bacillus suhtilis and Candida albicans. The saturated calcium hydroxide solution was effective against only four of the 11 microorganisms studied over a 60-min exposure time. The calcium hydroxide solutions con-taining detergent killed all 11 test organisms over a 30-min exposure time. This difference was statistically significant (P<0.01). No statistically significant difference in antimicrobial action was found between the 10% and 20% detergent calcium hydroxide solutions (F>0.01). However, the low surface tension (46.5 × 10?3 Nm?1) and high pH (10.8) of the calcium hydroxide solution with 20% detergent establish it as the more effective solution. 相似文献
70.
从34例牙髓根管感染中共分离出厌氧菌118株,经菌属分类依次为消化链球菌属,拟杆菌属,梭杆菌属,放线菌属,韦荣氏球菌属和珠网菌属,其中前3属为77株,分离率为65.3%,这一结果显示该3属细菌与极管感染有密切关系,是牙髓根管感染的优势菌。 相似文献