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121.
感官分析法和便携式硫化物检测仪检测口臭的相关性研究 总被引:2,自引:0,他引:2
目的比较感官分析法(鼻测法)和便携式硫化物检测仪(商品名Halimeter)检测口臭之间的准确性和一致性。方法首先对2名嗅辨员进行嗅觉检测试验,以确定其进行感官分析评分的资质。选择86例符合试验条件的受试者,分别用感官分析法评价口臭程度,硫化物检测仪检测口腔挥发性硫化物(VSC)含量,使用SPSS11.0软件分析鼻测法得分均值和VSC水平的关系。结果2名嗅辨员一致性良好,Kappa值达到0.568,P<0.01。鼻测法得分均值与Halimeter检测所得硫化物峰值之间相关系数r=0.538,P<0.01;与硫化物稳定值之间相关系数r=0.546,P<0.01。结论鼻测法得分和Halimeter检测的口腔VSC含量之间存在显著相关关系,提示Halimeter可在一定程度上作为鼻测法的辅助手段,用以检测口臭。 相似文献
122.
纯钛表面快速沉积羟基磷灰石涂层的实验研究 总被引:1,自引:0,他引:1
目的探讨在纯钛种植体表面快速沉积羟基磷灰石涂层的新方法。方法20片纯钛片均分为A、B两组。A组用H2SO54与HCI混合液酸蚀;B组用H2SO4与HCI混合液酸蚀,再用5mol/L NaOH溶液60℃处理24h后,600℃热处理1h。然后两组试件同时置于仿生液A液和B液中各1天。场发射扫描电子显微镜观察分析涂层的形貌。结果两组试件表面均可沉积致密的羟基磷灰石涂层,涂层由1—3μm的小球组成。X射线衍射分析证实其为碳酸化的羟基磷灰石。结论在纯钛表面可以快速沉积碳酸化的羟基磷灰石。 相似文献
123.
Brackett MG Li N Brackett WW Sword RJ Qi YP Niu LN Pucci CR Dib A Pashley DH Tay FR 《Journal of dentistry》2011,39(3):238-248
Objectives
The lack of durability in resin-dentine bonds led to the use of chlorhexidine as MMP-inhibitor to prevent the degradation of hybrid layers. Biomimetic remineralisation is a concept-proven approach in preventing the degradation of resin-dentine bonds. The purpose of this study is to examine the integrity of aged resin-dentine interfaces created with a nanofiller-containing etch-and-rinse adhesive after the application of these two approaches.Methods
The more established MMP-inhibition approach was examined using a parallel in vivo and in vitro ageing design to facilitate comparison with the biomimetic remineralisation approach using an in vitro ageing design. Specimens bonded without chlorhexidine exhibited extensive degradation of the hybrid layer after 12 months of in vivo ageing.Results
Dissolution of nanofillers could be seen within a water-rich zone within the adhesive layer. Although specimens bonded with chlorhexidine exhibited intact hybrid layers, water-rich regions remained in those hybrid layers and degradation of nanofillers occurred within the adhesive layer. Specimens subjected to in vitro biomimetic remineralisation followed by in vitro ageing demonstrated intrafibrillar collagen remineralisation within hybrid layers and deposition of mineral nanocrystals in nanovoids within the adhesive.Conclusions
The impact was realized by understanding the lack of an inherent mechanism to remove water from resin-dentine interfaces as the critical barrier to progress in bonding with the etch-and-rinse technique. The experimental biomimetic remineralisation strategy offers a creative solution for incorporating a progressive hydration mechanism to achieve this goal, which warrants its translation into a clinically applicable technique. 相似文献124.
125.
目的:新型钛合金Ti-24Nb-4Zr-7.9Sn(TNZS)经过阳极氧化(anodic oxidation,AD)技术处理后,分析其表面的人成骨样MG63细胞骨保护素(osteoprotegerin,OPG)、细胞核因子-κB受体活化因子配体(RANKL)基因表达水平.方法:将人成骨样MG63细胞接种于Ti-6Al-4V、TNZS、AD-TNZS表面,采用半定量RT-PCR法检测OPG、RANKL mRNA的表达量.结果:人成骨样MG63细胞在AD-TNZS表面的OPGm RNA表达量有所提高,而RANKL mRNA的表达量3组材料间无明显差异.结论:阳极氧化处理的TNZS钛合金可能通过影响骨保护素、细胞核因子-κB受体活化因子配体调节成骨细胞、破骨细胞的平衡,从而促进种植体植入后的骨重建. 相似文献
126.
小剂量地塞米松预防根管治疗期间慢性尖周炎急性发作的临床研究 总被引:3,自引:0,他引:3
目的 探讨小剂量地塞米松对根管治疗期间慢性尖周炎急性发作的预防作用。方法 90倒下前磨牙慢性尖周炎患者以年龄性别分层,随机化配对分成A、B、C三组:A组每日口服地塞米松1.5mg,每日2次;B组每日口服地塞米松1.5mg,每日1次;C组为空白对照。分别于根管预备后6、24、48小时记录VAS评分。结果 A、B组与C组VAS评分经方差分析,差异具有高度统计学意义。A、B组VAS评分均值t检验差异无统计学意义。结论每日口服地塞米松1.5mg可有效预防根管治疗期间慢性尖周炎急性发作。 相似文献
127.
目的:研究不同年龄阶段健康成人的刺激性全唾液流速及唾液一氧化氮含量的变化。方法:将97例健康成人分成4个年龄组,分别为青龄组(20~39岁)、中龄组(40~59岁)、老龄组(60~79岁)、长寿组(80岁以上)。在上午8:00~10:00空腹,以2.5ml/L洗必太漱口,以20ml/L柠檬酸刺激舌背前1/3,以双蒸水漱口后采集全唾液5min,记录样本容量,并计算其流速。用硝酸还原酶法检测唾液中NO浓度,并计算其唾液中NO的单位时间含量。结果:(1)青龄组刺激性全唾液流速高于中龄组、老龄组、长寿组(P<0.05);中龄组、老龄组、长寿组之间唾液流速无显著性差异(P>0.05);(2)不同年龄组间两两比较,刺激性全唾液NO浓度无显著性差异(P>0.05);青龄组NO单位时间含量显著高于中龄组、老龄组和长寿组(P<0.05),中龄组、老龄组、长寿组之间的NO单位时间含量无显著性差异(P>0.05)。结论:(1)中老年人群的刺激性全唾液流速显著低于青年人群;(2)随年龄增长,健康成人刺激性全唾液中的NO浓度未发生明显变化,但其单位时间含量呈降低趋势。 相似文献
128.
129.
正畸儿童龋病的口腔综合防治 总被引:4,自引:0,他引:4
目的:观察口腔综合防治措施对正畸儿童龋病的作用。方法:以56名12-16岁的正畸患者为观察对象,观察矫治前、矫治后半年及1年的龋指数、变形链球菌计数、乳酸杆菌计数的改变。实验组采用口腔综合保健措施。结果:实验组的变形链球菌计数、乳酸杆菌计数明显低于对照组,差异有显著性;实验组无新龋发生,对照组龋均比实验组有所上升,但两组之间无统计学上的差异。结论:正畸治疗患者龋病通过口腔综合防治措施是可以治疗和预防的。 相似文献
130.
Prospective evaluation of implants connected to teeth 总被引:1,自引:0,他引:1
Block MS Lirette D Gardiner D Li L Finger IM Hochstedler J Evans G Kent JN Misiek DJ Mendez AJ Guerra L Larsen H Wood W Worthington P 《The International journal of oral & maxillofacial implants》2002,17(4):473-487
PURPOSE: This prospective clinical trial examined the effect on teeth and implants when rigidly or non-rigidly connected in a cross-arch model. MATERIALS AND METHODS: Thirty patients received 2 implants, 1 on each side of the mandible, and were restored with 3-unit fixed partial dentures connected either rigidly or non-rigidly to an abutment tooth. Patients were followed for at least 5 years post-restoration. RESULTS: Repeated-measures analysis revealed no significant difference in crestal bone loss at implants (rigid versus non-rigid methods). An overall significant difference (P < .001) was found comparing methods for teeth. Paired t tests revealed no significant differences in crestal bone levels for implants or teeth at the 5-year recall. Kaplan-Meier methods and the Cox proportional hazards model showed no differences between attachment methods with regard to success based on survival and bone loss criteria. During the 5-year recall period, 1 implant (rigid side) was removed. Four implants developed bone loss greater than 2 mm during the course of this trial. One tooth on the rigid side and 2 teeth on the non-rigid side had greater than 2 mm of crestal bone loss and were removed secondary to fractures. In all, 5 abutment teeth were removed, all of which had been treated with root canal therapy and fractured at the interface of the post within the tooth. There was no clear relationship of tooth fracture to attachment. Repeated-measures analysis of mobility values revealed no significant changes over the time course of this study, and paired t tests revealed no statistically significant differences between implants for mobility. Repeated-measures analysis and paired t tests for probing depth revealed no significant changes over the time course of this study. There were no significant differences in soft tissue indices for either attachment method. The percentage of patients who had measurable intrusion was 66% for the non-rigid group, and 44% for the rigid group; 25% of the non-rigid teeth had greater than 0.5 mm intrusion, compared with 12.5% for the rigid group. For the 2 time periods evaluated, there was no significant increase in intrusion over time. The non-rigid-side implant required more nonscheduled visits to treat problems than the rigid implant and the teeth. Discussion: Most patients were treated successfully with rigid or non-rigid attachment of implants to teeth. CONCLUSION: The high incidence of intrusion and non-scheduled patient visits suggest that alternative treatments without connecting implants to teeth may be indicated. 相似文献