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991.
Creative approaches to tooth maintenance often include tooth resection and retention of one or more of the roots. Although this procedure is reasonably successful, failure of supportive endodontic, periodontic, and restorative management of the retained roots can jeopardize a successful outcome. The following is a case report evaluating multiple aetiologies contributing to root resection failure.  相似文献   
992.
Following extraction of a symptomatic mandibular premolar which had been subjected to two periradicular surgical procedures, significant apical healing was identified histologically. The implications of these findings are discussed in relation to contemporary advocated treatment regimens, case assessment, and interpretation for success and failure.  相似文献   
993.
目的:探讨口腔龈下菌斑中血链球菌、中间普氏菌与冠心病的关系。方法:检查与记录60例研究对象(冠心病组与对照组各30例)的牙龈指数(GI)、菌斑指数(PLI)、牙周袋探诊深度(PD)。应用生化法检测两组研究对象龈下菌斑中的血链球菌数,并用定性随机引物酶链反应法对两组研究对象龈下菌斑中的中间普氏菌进行了鉴定。结果:冠心病组的PD、PLI和龈下菌斑中的血链球菌数及中间普氏菌检出率明显高于对照组(P(0.05)。结论:冠心病组的牙周健康状况相对更差,与冠心病有关的口腔细菌除血链球菌外,龈下菌斑中的中间普氏菌也与冠心病的发病关系密切。  相似文献   
994.
Background: The aim of this study was to evaluate the cardiovascular effects of maxillary infiltration using 2% lidocaine with 1:100 000 adrenaline, 4% articaine with 1:200 000 adrenaline, and 4% articaine with 1:100 000 adrenaline in different stages during restorative dental procedures. Methods: Twenty healthy patients randomly received 1.8 mL of the three local anaesthetics. Systolic blood pressure, average blood pressure, diastolic blood pressure, and heart rate were evaluated by the oscillometric and photoplethysmograph methods in seven stages during the appointment. Results: Statistical analysis by ANOVA and Tukey tests of cardiovascular parameters did not show significant differences between the anaesthetic associations. There were significant differences for the parameters among different clinical stages. Conclusions: The variation of cardiovascular parameters was similar for lidocaine and articaine with both adrenaline concentrations and showed no advantage of one drug over the other. Cardiovascular parameters were influenced by the stages of the dental procedures, which showed the effect of anxiety during restorative dental treatment.  相似文献   
995.
透明质酸在慢性牙周炎治疗中的作用   总被引:3,自引:0,他引:3       下载免费PDF全文
目的 观察局部应用外源性透明质酸(HA)对慢性牙周炎的临床疗效。方法 采用口内自身对照的研究方法。选择20例慢性牙周炎患者的患牙306颗,其中150颗患牙为对照组,156颗为实验组。对照组患牙仅作洁刮治和根面平整(SRP)。实验组患牙在行SRP后,龈下辅助给予0·2%透明质酸凝胶。观察两组患牙的菌斑指数、龈沟液流速、龈沟出血指数、牙周探诊深度和临床附着水平等临床指标的动态变化。结果 对照组和实验组患牙的各临床指标在治疗后均显著改善,实验组患牙龈沟液流速的下降显著快于对照组(P=0·001),但其余临床指标两组间的差异无显著性。结论 本研究未发现HA结合SRP对治疗慢性牙周炎在牙周组织修复再生中有促进作用; HA能迅速减轻牙周组织的炎症反应。  相似文献   
996.
三种根管预备器械预备弯曲根管的临床研究   总被引:2,自引:0,他引:2  
目的 比较三种根管预备器械预备后牙弯曲根管的临床情况 ,从而评价镍钛机动根管预备器械的临床应用前景。方法 研究对象为年轻下颌第一恒磨牙 30例 ,分别采用手动不锈钢器械、手动镍钛器械和机动镍钛器械进行根管预备 ,治疗前后分别拍摄可高度重叠的X线片 ,通过计算机扫描和放大比较根管拉直情况以及根尖孔敞开、台阶和侧穿的发生率。并记录各组的操作时间和器械折断发生率。结果 对于低度弯曲的根管 ,不锈钢组比镍钛组更易造成根管拉直 (P <0 .0 1)。对于高度弯曲的根管来说 ,不锈钢组与镍钛组 ,相差更为明显 (P <0 .0 1)。治疗失败在各组均有发生 ,操作时间机动组比手动组要快 (P <0 .0 1)。结论 机动镍钛根管预备器械具有良好的临床应用前景  相似文献   
997.
BACKGROUND: The authors assessed the utilization of oral health care professionals (OHCPs) as a resource for identifying patients who were unaware of their increased risk of developing cardiovascular disease (CVD). METHODS: OHCPs administered a CVD risk-screening questionnaire, measured blood pressure and tested cholesterol levels, high-density lipoprotein levels and hemoglobin A1c (HgA1c) levels using "finger-stick" blood testing in 100 patients treated in a dental school clinic who were unaware of their CVD risk status. The authors determined the prevalence of specific risk factors (that is, smoking and abnormal levels of systolic blood pressure, lipids, body mass index and HgA1c) and calculated Framingham 10-year coronary heart disease (CHD) risk scores. RESULTS: Seventeen percent of the 100 patients (35 percent of men, 5 percent of women) had an increased global risk of experiencing a CHD event within 10 years (Framingham risk score>10 percent). Seventy-three percent of participants had one or more risk factors and 31 percent had two or more risk factors present. More men than women had low levels of high-density lipoprotein (45 percent [18/40] of men versus 3.3 percent [2/60] of women; P<.0001). The mean Framingham CHD risk score increased with increasing risk factor burden. CONCLUSIONS: OHCPs identified patients with an increased CHD risk who could benefit from primary prevention activities. A substantial proportion of study patients who were unaware of their risk status were at an increased risk of experiencing a CHD event within 10 years. OHCPs could contribute to public health CHD control efforts.  相似文献   
998.
OBJECTIVE: To investigate the fracture strength and pattern of failure of teeth with weakened roots reconstructed by different procedures. METHODS: In an in vitro study root posts were placed in 50 endodontically treated canines, divided into 5 groups (n=10) as follows: cast metallic post; glass fibre post with smaller diameter than the root canal; glass fibre post with smaller diameter than the root canal + glass fibre strips; glass fibre post with smaller diameter than the root canal + accessory glass fibre posts; anatomical post (glass fibre post with smaller diameter than the root canal, relined with low viscosity composite resin). Posts were luted with resin cement and the coronal portion of posts was constructed with composite resin. Metallic crowns were cemented on the posts. Specimens were submitted to compressive load in a universal testing machine. Fracture strength values of each group were compared. RESULTS: Fracture strength values were for Groups 1-5 respectively: 1087.06; 745.69; 775.41; 920.64; 876.12kgf, with significant differences between Groups 1 and 2 and between Groups 1 and 3 (p<0.05). Observed patterns of fracture were: Group 1 - 100% of roots fractured; Groups 2 and 4 - variable fracture modes; Group 3 - 60% of fractures occurred in the cervical root third; Group 5 - 50% of failures occurred in the coronal portion of the post. CONCLUSIONS: The fracture strength of teeth with cast metallic posts, teeth with anatomical posts or teeth with glass fibre posts combined with accessory posts was similar. All teeth restored with cast metallic posts presented fractures and were unfavourable to maintenance of the remaining tooth structure. Teeth with fibre posts (Groups 2 to 5) presented variable fracture modes; however, the maximum percentage of unfavourable fractures was 30%.  相似文献   
999.
ABSTRACT

Objective: The aim of this study was to correlate degree of depression, somatization, and chronic pain in asymptomatic women with clinical findings, using Research Diagnostic Criteria/Temporomandibular disorders (RDC/TMD).

Methods: A total of 200 female participants, ages 18–65, filled out a standard RDC/TMD axis II form for the assessment of chronic pain, disability, depression, and non-specific physical symptoms and underwent clinical examination of the temporomandibular joint. Correlation of clinical findings (axis I) and axis II assessment was performed using Spearman’s correlation test, with significance set at p < 0.05.

Results: There was a significant correlation between depression scores (p < 0.04), chronic pain (p < 0.001), and non-specific physical symptoms without questions about pain (p = 0.008).

Discussion: The highest scores on the Graded Chronic Pain Scale were observed in patients with arthralgia, while patients with myofascial pain scored higher on depression and somatization tests.  相似文献   
1000.
Abstract This study investigated levels of hyaluronan and chondroitin-4-sulphate in the crevicular fluid of patients with chronic adult periodontitis at diseased and healthy sites before and after treatment. The relationship between clinical diagnostic parameters and levels of glycosaminoglycans in gingival crevicular fluid were also analysed. Within each patient. 4 sites either mesial or distal and on single rooted teeth were classified as diseased or healthy using a modified gingival index, pocket depth and attachment loss. Crevicular fluid was collected from each site using glass micropipettes and analysed for glycosaminoglycan content by cellulose acetate electrophoresis. Significantly higher levels of chondroitin-4-sulphate were detected at diseased sites prior to treatment correlating with increased pocket depth or attachment levels. Following a period of treatment consisting of oral hygiene instruction and root planing, the patients were reassessed for their response to treatment by measuring the modified gingival index, pocket depth, attachment loss and levels of glycosaminoglycans. Analysis of glycosaminoglycan levels at diseased sites that demonstrated a poor response to treatment also demonstrated significantly higher levels of chondroitin-4-sulphate than those sites that responded well to treatment. Hyaluronan levels were less significantly associated with clinically succesful treatment. This study confirmed the use of the sulphated glycosaminoglycan chondroitin-4–sulphate as a potential diagnostic aid of periodontal tissue destruction; however, further longitudinal studies are required to assess their performance.  相似文献   
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