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991.
口外唇弓配合滑动直丝弓技术矫治双颌前突畸形   总被引:4,自引:0,他引:4  
目的:分析口外唇弓配合滑动直丝弓技术矫治双颌前突畸形的临床效果。方法:利用口外唇弓配合滑动直丝弓技术矫治非生长期双颌前突畸形患者12名,均拔除4个第一双尖牙,采用一步或两步滑动法关闭拔牙间隙。将矫治前后的头颅侧位定位片进行测量分析,结果进行配对t检验。结果:矫治后上下切牙明显内收,上下唇突度明显减小(P<0. 001),Z角增加(P<0. 01);而上下磨牙前移量较小,平均分别为2. 33mm和2. 61mm。结论:口外唇弓配合滑动直丝弓技术可相对高效简便地矫治双颌前突畸形,能较好地控制支抗,显著改善患者的侧貌。  相似文献   
992.
目的:研究靶控输注异丙酚复合吸入安氟醚在颌面部手术麻醉中的可行性及推广价值。方法:116例ASAⅠ~Ⅱ级口腔颌面部手术病人,随机分为靶控组和恒速组。常规静脉麻醉诱导后行气管内插管,维持期间机械通气,靶控组采用血浆靶控输注技术泵入异丙酚,同时复合吸入1%~2%安氟醚。恒速组采用速率为4~6mg·kg-1·mL-1输入异丙酚,同时吸入安氟醚。分别在诱导前、插管即刻、插管后5min、切皮时、缝皮、拔管前、拔管后几个时点记录BP,HR,SPO2和,并与诱导前进行统计学比较;记录入睡时间和苏醒时间,两组间进行比较。结果:与诱导前比较,在插管后5minSBP、DBP下降明显,MAP则无明显变化,两组相比,入睡时间无明显差异,苏醒时间靶控组明显短于恒速组。结论:靶控输注异丙酚联合应用吸入安氟醚,麻醉效果好,能预测病人的苏醒时间,清醒质量高,是一种经济实用的良好搭配。  相似文献   
993.
23例27个粗大根管的根管治疗及修复临床观察   总被引:1,自引:0,他引:1  
目的 :观察 2 3例 2 7个粗大根管的根管治疗及修复效果并总结治疗经验。方法 :对 2 7个根管未完全发育成形的残根、残冠进行根管治疗及修复 ,随访 2年观察治疗效果。结果 :2 7个粗大根管在根管治疗过程中 ,2 3个牙经化学根管预备后即产生良好的根充效果 ,3个牙仅作机械根管预备而未作化学预备的患牙首次根管治疗失败 ,采用化学预备重新根充效果良好 ,1个牙反复出现瘘管而拔除。自制牙胶尖未发生超充情况。修复后有 7个牙出现根折 ,其余均修复效果良好。结论 :利用化学方法对粗大根管进行预备是必须的 ,采用自制牙胶尖进行根管充填能形成良好的根尖封闭。修复的关键在于尽量保留牙体组织。牙颈部需形成“颈箍” ,肩台必须位于正常牙体组织上。  相似文献   
994.
OBJECTIVES: The objectives of the present study include investigation of the relationship between attitudes and desires with respect to oral health at initial office visit and compliance with supportive periodontal treatment (SPT) and identification of prognostic factors with respect to low-compliance with SPT. MATERIALS AND METHODS: Four hundred thirty-one patients were evaluated. Subjects completed a questionnaire concerning attitude and desire with respect to oral health and subjective symptoms prior to periodontal treatment. Survival probabilities of SPT were estimated by the Kaplan-Meier method and compared between answers for each item of the questionnaire via the Cox-Mantel test. Finally, a multivariate Cox proportional hazards regression model was constructed, which included age and gender. RESULTS: Greater than 95% of participants desired toothbrushing proficiency and lifelong retention of teeth at the initial office visit; however, the overall survival probabilities of SPT were only 52.7% after about 5 years. Patients exhibiting unfavourable attitudes toward oral health at the initial office visit, in comparison with those displaying favourable attitudes, exhibited greater tendency to abandon SPT. A Cox regression model revealed that lack of brushing on the gingival margin, non-use of an inter-dental brush or dental floss, non-use of fluoride toothpaste and frequent consumption of sugar-containing drinks were significant independent prognostic factors for low-compliance with SPT (p<0.05; Hazard ratios=2.27, 2.00, 2.56 and 2.06, respectively). CONCLUSIONS: Desire for satisfactory oral health is not related consistently to continuation of SPT. Unfavourable attitudes toward oral health were correlated to low-compliance with SPT. Clinicians may wish to establish methods for improvement of patient compliance employing behavioural approaches applicable to the attitudes of potential low-compliance individuals.  相似文献   
995.
目的 :探讨瓷与牙釉质粘结时不同瓷粘结系统与瓷表面处理方式的优化组合。方法 :以不同的瓷粘结系统和表面处理方式为影响因素 ,将瓷片分成 8组 ,分别与釉质粘结 ,测其剪切强度 ,统计分析所得数据 ,观察其断裂方式。结果 :处理组中以不喷砂磷酸酸蚀组的粘结强度最低 ,其余各组间无统计学差异。PanaviaF组剪切强度均值最高为 2 9.3 8MP ,邦多为 2 6.19MP。结论 :PanaviaF和邦多陶瓷粘结系统结合喷砂后磷酸酸蚀和HF酸蚀使用都可获得理想的粘结效果  相似文献   
996.
羟基磷灰石涂层热处理晶化工艺研究   总被引:13,自引:0,他引:13  
目的:通过热处理方法提高羟基磷灰石(HA)涂层的结晶度、使脱落的羟基得到恢复。方法:通过等离子喷涂和热处理试验,利用X射线衍射(XRD)和红外吸收光普分析等手段研究了热处理对羟基磷石涂层相组成的影响。结果:热处理可使涂层中的非晶相发生晶化,并使羟基得到恢复;随着热处理温度的提高,涂层的结晶度提高,α-TCP等热分解相逐步转变为羟基磷灰石。保温时间达到2小时后,延长保温时间并不能提高涂层的结晶工。结论:在大气环境下,涂层的最佳热处理工艺是在700℃下保温2小时。  相似文献   
997.
OBJECTIVE: To analyse whether developing countries have sufficient health dollars to treat existing diseases in general and dental caries in particular in their child population. METHODS: Assessments of the costs of treating existing and future caries by the conventional approach. Analysis of WHO dental databases and spreadsheet calculations of costs based upon population projections, prevalence and trends in patterns of caries. FINDINGS: Even though the caries levels are low and most of the disease occurs on the occlusal and the buccal/lingual surfaces, more than 90% of the dental caries remains untreated in Third World countries. Calculations reveal that to restore the permanent dentition of the child population of low-income nations using traditional amalgam restorative dentistry would cost between pounds 1,024 ($US1618) and pounds 2,224 ($US3513) per 1,000 children of mixed ages from 6 to 18 years. This exceeds the available resources for the provision of an essential public health care package for the children of 15 to 29 low-income countries. CONCLUSIONS: To treat caries with the traditional method of restorative dentistry is beyond the financial capabilities of the majority of low-income nations, as three-quarters of these countries do not even have sufficient resources to finance an essential package of health care services for their children.  相似文献   
998.
AIM: To study the presence, levels and molecular forms of matrix metalloproteinase (MMP) -8 (collage-nase-2) in pulpal and periapical inflammation, and the changes in MMP-8 levels in root-canal exudates during root-canal treatment. METHODOLOGY: Periapical exudate samples were collected from 11 necrotic teeth with radiographically verified periapical periodontitis during three root-canal treatment visits with interappointment calcium hydroxide (Ca(OH)2) medication. MMP-8 levels and molecular forms were analyzed with immunofluorescent assay (IFMA) and Western immunoblot. Inflamed pulp tissue and periapical granuloma tissue (n = 10 for both) were obtained from other patients and used for MMP-8 immunohistochemical (IHC) staining. RESULTS: The periapical exudate samples demonstrated marked differences in MMP-8 levels between the teeth in the first visit and significant decrease in MMP-8 levels during the root-canal treatment (P = 0.0107). One specimen failed to show a decrease in MMP-8 below 1000 ng mL(-1) a vertical root fracture was later diagnosed and the tooth extracted. IHC staining showed that in addition to PMN-leucocytes, macrophages and plasma cells produced MMP-8 in pulp and periapical granulomas. CONCLUSIONS: The findings demonstrate the presence of MMP-8 in the inflamed pulp and periapical tissue, indicating that MMP-8 has a role in pulpal and periapical inflammation, most likely participating in tissue extracellular matrix degradation. They further indicate that MMP analysis from periapical exudate could be used to indicate and monitor inflammatory activity and the success of treatment in teeth with periapical lesions.  相似文献   
999.
AIM: The objective of this study was to audit the quality of root canal treatment performed by undergraduate students on adult patients. METHODOLOGY: All root canal treatment completed by first and second clinical year undergraduates over a 12-month period were included in the study. The availability and readability of pretreatment, diagnostic length, try-in point and postoperative radiographs were noted for each case. All readable postoperative radiographs of primary treatments were examined for quality of the root filling, categorized as complete, incomplete apical, incomplete apical and lateral or not assessable. The distance from the radiographic apex of the root to the apical extent of each root filling was measured to 0.1 mm precision. RESULTS: Undergraduates performed primary treatment on 157 teeth. A postoperative radiograph was available in 97% of cases. A try-in point radiograph was unavailable in one-fifth of cases. Twenty-seven teeth (13%) were categorized as satisfactory in terms of both radiographic quality and distance of the root filling from the radiographic apex. CONCLUSIONS: Overall, the technical quality of root canal treatment completed by undergraduate students was poor.  相似文献   
1000.
The use of ITI implants for rehabilitation of the edentulous patient has shown predictable results not only in the standard sites but also in cases of advanced alveolar ridge atrophy. Preoperative analysis, including clinical and radiological evaluation, implant selection, and determination of implant number and distribution in the edentulous maxilla and mandible, is described in this article. The surgical procedures used in standard sites are presented, the benefits of a nonsubmerged surgical approach in these cases are emphasized, and a protocol for postoperative management is recommended. Augmentation procedures in advanced osseointegration surgery call for submerged ITI implants when a simultaneous approach is chosen. Several types of advanced implant surgery that can be used are described, including membrane technique, sinus lift procedures, vertical ridge augmentation with iliac bone grafts, and correction of sagittal jaw relationship.  相似文献   
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