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1.
ENAMEL MATRIX DERIVATIVE (EMDOGAIN®) FOR PERIODONTAL TISSUE REGENERATION IN INTRABONY DEFECTS (Cochrane Review). In: THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS, ISSUE 4, 2005.Esposito M, Grusovin MG, Coulthard P, Worthington H

Background

Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth-supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG), and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development.

Objectives

The objectives were to test whether EMD is effective, and to compare EMD versus GTR and various BG procedures for the treatment of intrabony defects.

Search strategy

We searched the Cochrane OHG Trials Register, Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE. Several journals were hand searched. No language restrictions were applied. Authors of randomized controlled clinical trials (RCTs) who were identified, personal contacts, and the manufacturer were contacted to identify unpublished trials. The most recent search was May 2005.

Selection criteria

Selected studies were RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR, and various BG procedures with at least 1 year of follow-up. The outcome measures considered were tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, esthetics, and adverse events. The following time points were to be evaluated: 1, 5, and 10 years.

Data collection & analysis

Screening of eligible studies, assessment of the methodological quality of the trials, and data extraction were conducted in duplicate and independently by 2 authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CI). It was decided not to investigate heterogeneity, but a sensitivity analysis for the risk of bias of the trials was performed.

Main results

Ten trials were included out of 29 potentially eligible trials. No included trial presented data after 5 years of follow-up, therefore all data refer to the 1-year time point. A meta-analysis including 8 trials showed that EMD-treated sites displayed statistically significant PAL improvements (mean difference 1.2 mm, 95% CI 0.7 to 1.7) and PPD reduction (0.8 mm, 95% CI 0.5 to 1.0) when compared to placebo or control treated sites, although a high degree of heterogeneity was found. Significantly more sites had less than 2 mm PAL gain in the control group, with RR 0.48 (95% CI 0.29 to 0.80). Approximately 6 patients needed to be treated (NNT) to have 1 patient gaining 2 mm or more PAL over the control group, based on a prevalence in the control group of 35%. No differences in tooth loss or esthetic appearance as judged by the patients were observed. When evaluating the only 2 trials at a low risk of bias in a sensitivity analysis, the effect size for PAL was 0.6 mm, which was less than 1.2 mm for the overall result. Comparing EMD with GTR (5 trials), GTR showed a statistically significant increase of REC (0.4 mm) and significantly more postoperative complications. No trials were found comparing EMD with BG.

Reviewers' conclusions

One year after its application, EMD significantly improved PAL levels (1.2 mm) and PPD reduction (0.8 mm) when compared to a placebo or control, however, the high degree of heterogeneity observed among trials suggests that results have to be interpreted with great caution. In addition, a sensitivity analysis indicated that the overall treatment effect might be overestimated. The actual clinical advantages of using EMD are unknown. With the exception of significantly more postoperative complications in the GTR group, there was no evidence of clinically important differences between GTR and EMD.

Abstract

INTERVENTIONS FOR REPLACING MISSING TEETH: DENTAL IMPLANTS IN ZYGOMATIC BONE FOR THE REHABILITATION OF THE SEVERELY DEFICIENT EDENTULOUS MAXILLA (Cochrane Review). In: THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS, ISSUE 4, 2005.Esposito M, Worthington HV, Coulthard P

Background

Dental implants are used for replacing missing teeth. Placing dental implants is limited by the presence of adequate bone volume permitting their anchorage. Several bone-augmentation procedures have been developed to solve this problem. Zygomatic implants are long screw-shaped implants developed as a partial or complete alternative to bone augmentation procedures for the severely atrophic maxilla. One to 3 zygomatic implants can be inserted through the posterior alveolar crest and maxillary sinus to engage the body of the zygomatic bone. A couple of conventional dental implants are also needed in the frontal region of the maxilla to stabilize the prosthesis. The potential main advantages of zygomatic implants could be that in some situations bone grafting may not be needed and a fixed denture could be fitted sooner. Another specific indication for using zygomatic implants could be the need for maxillary reconstruction after maxillectomy in cancer patients.

Objectives

The objective was to test the hypothesis of no difference in outcomes between zygomatic implants with and without bone-augmenting procedures in comparison with conventional dental implants in augmented bone for severely resorbed maxillae.

Search strategy

We searched the Cochrane Oral Health Group's Trial Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and EMBASE. We hand searched several dental journals. No language restrictions were applied. Personal contacts and all known zygomatic implant manufacturers were contacted to identify unpublished trials. The most recent search was May 2005.

Selection criteria

Studies selected were randomized controlled clinical trials (RCTs) that included patients with severely resorbed maxillae who could not be rehabilitated with conventional dental implants and were treated with zygomatic implants with and without bone grafts versus patients treated with conventional dental implants in conjunction with bone-augmentation procedures having a follow-up of at least 1 year. Outcome measures considered were prosthesis and implant failures, side effects, patient satisfaction, and cost-effectiveness.

Data collection & analysis

Screening of eligible studies, assessment of the methodological quality of trials, and data extraction were to be conducted in duplicate and independently by 2 authors. Results were to be expressed as random-effects models using weighted mean differences for continuous outcomes and risk ratio for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated including both clinical and methodological factors.

Main results

No RCTs or controlled clinical trials (CCTs) were identified.

Reviewers' conclusions

There is the need for RCTs in this area to assess whether zygomatic implants offer some advantages over alternative bone-augmentation techniques for treating atrophic maxillae.  相似文献   
2.
目的:探讨肺隔离症的手术治疗方法和效果。方法回顾性分析该院在2003年3月-2014年3月间收治的17例肺隔离症患者的临床资料。结果①该组17例患者中,术前确诊者13例;术中确诊4例;②采用肺叶切除术对患者进行治疗,全部痊愈,无1例死亡;③术后并发症的发生率为17.64豫(3/17),经对症处理后均缓解;④术后随访6个月~10年,复查X线胸片和CT,结果显示均正常。结论肺隔离症是临床中比较少见的肺先天性畸形,临床表现无特异性,易发生误诊和漏诊,临床中以肺叶切除术治疗为主,效果良好,值得临床推广。  相似文献   
3.
隐性高血压病人中心动脉压及增强指数   总被引:6,自引:0,他引:6  
目的探讨“隐性高血压”与中心动脉压及动脉硬化的关系。方法采用脉搏波分析仪记录89例临床诊断为血压正常(偶测血压<140/90 mm Hg)及75例高血压(偶测血压≥140/90 mm Hg或正在服用降压药物者)患者的桡动脉脉搏波,经计算机自动转换为相应的中心动脉脉搏波,并分析中心动脉压力及反映全身动脉硬化的增强指数(AIx)。结果小样本人群中,隐性高血压的患病率为15.7%。与血压正常(偶测血压<140/90 mm Hg及白昼动态血压<135/85 mm Hg)组相比,隐性高血压组的血浆总胆固醇及低密度脂蛋白胆固醇浓度、饮酒的比例显著增高;中心动脉收缩压、舒张压、收缩末期压及中心动脉增强压分别增加14.8 mm Hg(CI5.6~24.0 mm Hg)、9.1 mm Hg(CI3.1~15.1 mm Hg)、14.0mm Hg(CI5.8~22.2)及4.2(CI0.6~7.8 mm Hg),增强指数增加11.9%(CI2.8%~20.9%)。虽然隐性高血压组的偶测血压显著低于高血压组,经年龄、性别及身高调整后,两组的白昼动态血压、中心动脉收缩压、舒张压、增强压及增强指数均无显著差异。结论隐性高血压患者的中心动脉压力及增强指数升高,提示动脉顺应性下降,动脉硬化。这些血液动力学的改变可能增加心血管病危险,对其进行评价有助于偶测血压正常者的危险分层。  相似文献   
4.
5.
6.
目的 分析普通窄带成像(NBI)内镜下结直肠增生性息肉与腺瘤腺管及微血管特征的差异,评价NBI的鉴别诊断价值.方法 将普通内镜下诊断结直肠息肉、病理检查证实为增生性息肉或腺瘤者纳入研究并进行NBI内镜检查.将腺管形态参照改良的工藤分型法分为A型和B型.将微血管形态分为3型,无微血管判为Ⅰ型,微血管沿腺管开口排列、粗细均匀判为Ⅱ型,微血管粗细不均、排列紊乱判为Ⅲ型.比较增生性息肉和腺瘤NBI图像中腺管形态和微血管形态特征的差异,同时对无放大NBI图像观察者间的一致性进行评价.结果 共87例患者的107个息肉(腺瘤73个、增生性息肉34个)进行普通NBI内镜检查.腺瘤组息肉最大径和表面分叶者比例明显高于增生性息肉组(P值分别=0.0023和0.0047).腺瘤组中B型腺管形态[86.3%(63/73)]及Ⅱ或Ⅲ型微血管形态[82.2%(60/73)]者较多.以B型腺管形态、Ⅱ型或Ⅲ型微血管中任一特征诊断腺瘤的敏感度、特异度、准确率分别为97.3%、82.4%、92.5%.以B型腺管形态联合Ⅱ型或Ⅲ型微血管诊断腺瘤的敏感度、特异度、准确率分别为71.2%、91.2%、77.6%.观察者间一致性评价平均Kappa值为0.761.结论 普通NBI内镜下结直肠腺瘤和增生性息肉的微血管特征和腺管特征存在差异,依据以上两方面可在NBI内镜下实时初步鉴别腺瘤和增生性息肉.  相似文献   
7.
Behind the multiple arguments for and against the use of premedication, sedative drugs in children is a noble principle that of minimizing psychological trauma related to anesthesia and surgery. However, several confounding factors make it very difficult to reach didactic evidence-based conclusions. One of the key confounding issues is that the nature of expectations and responses for both parent and child vary greatly in different environments around the world. Studies applicable to one culture and to one hospital system (albeit multicultural) may not apply elsewhere. Moreover, the study of hospital-related distress begins at the start of the patient's journey and ends long after hospital discharge; it cannot be focused completely on just the moment of anesthetic induction. Taking an example from actual practice experience, the trauma caused by the actual giving of a premedication to a child who absolutely does not want it and may struggle may not be recorded in a study but could form a significant component of overall effect and later psychological pathology. Clearly, attitudes by health professionals and parents to the practice of routine pediatric premedication, vary considerably, often provoking strong opinions. In this pro–con article we highlight two very different approaches to premedication. It is hoped that this helps the reader to critically re-evaluate a practice, which was universal historically and now in many centers is more selective.  相似文献   
8.
9.
The aim of this trial was to compare the efficacy of combinationantithrombotic therapy with a prostacyclin-sparing aspirin plusanticoagulation versus conventional aspirin plus anticoagulation,when added to antianginal therapy, in patients with unstableangina or non-Q wave myocardial infarction already being treatedwith aspirin. In a double-blind (for the aspirin) study, 144prior aspirin users were randomized; 72 patients received controiled-release,prostacyclin-sparing aspirin 75 mg daily plus anticoagulation(intravenous heparin followed by warfarin to maintain the internationalnormalized ratio at 2–3), and 72 patients received conventionalaspirin 75 mg daily plus the same anticoagulation. Controlled-releaseaspirin was formulated to preserve endothelial cell prostacyclinsynthesis. Trial therapy was begun by 13.2 ± 12.3 h ofqualifying pain, and continued for 12 weeks. The frequency of recurrent angina with electrocardiographicchanges, myocardial infarction, or death, was analysed by intentionto treat. At 12 weeks, events were  相似文献   
10.
The relation of central haemodynamic changes to subsequent mortalityand peak enzyme activity was investigated in 190 patients withacute myocardial infarction. The mean delay time from onsetof symptoms to the haemodynamic study was 7.2 hours. Major exclusioncriteria were heart rate < 65beats min–1, systolicblood pressure < 105 mmHg and lung rales to a distance of> 10 cm above the lung bases. Nine patients (4.7%) died within15 days and 16 patients (8.4%) within 90 days after the infarction.Compared to survivors, non-survivors were characterized by baselinedepression of cardiac index, stroke volume index and left ventricularstroke work index, while pulmonary capillary wedge pressureand peripheral resistance were increased. However, a wide overlapbetween survivors and non-survivors makes the predictive valuelow in the individual patient. Peak serum aspartate aminotransferase (S-ASAT) activity wasweakly related to baseline pulmonary capillary wedge pressure(r = 0.28; P< 0.001) and stroke volume index (r = –0.22;P7lt;0.01). The correlation to pulmonary capillary wedge pressurewas only found in anterior (r = 0.34) infarcts. Peak serum lactatedehydrogenase (LD1) was not correlated with baseline haemodynamics.  相似文献   
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