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1.
目的 比较龋蚀检知液Caries detector和10% 优碘对离体牙龋坏牙体组织的检测效果,为临床应用提供实验室依据。 方法 选择有龋坏的离体牙80颗,分为Caries detector组和10% 优碘组,每组各40颗,再按龋坏深度分为Caries detector浅龋组,Caries detector深龋组,10%优碘浅龋组及10%优碘深龋组,每组20颗。分别记录各离体牙原始质量为G1,使用挖匙去腐后,再次记录各离体牙质量为G2,分别涂布Caries detector与10%优碘,使用挖匙去腐后再次记录离体牙质量为G3。观察各组腐质去除情况,计算并比较各组腐质清除率。 结果  Caries detector或是10%优碘都有明显的染色效果,Caries detector的染色范围大于10%优碘,并且在清除染色牙本质后仍有不易移除的残留染剂在更深层的牙本质中。Caries detector浅龋组腐质清除率高于10%优碘浅龋组,差异有统计学意义(P<0.05); Caries detector深龋组染色后腐质清除率高于10%优碘深龋组,差异有统计学意义(P<0.001)。 结论 Caries detector在浅龋的腐质去除上有着卓越的染色效果,但是对于患有深龋的牙齿,建议使用10%的优碘,会有较好的效果。  相似文献   
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微创开髓(conservative endodontic access cavity,CEC)是微创根管治疗术的第一步,经CEC治疗后的患牙较大程度保留了牙尖嵴和颈周牙本质等牙体硬组织,对于减少患牙的牙体流失及增强远期疗效具有重要意义。CEC存在多种入路方式及相应的洞型。确定髓腔入路的方法包括X线片定位法、显微CT/锥形束CT定位法以及数字化导板定位法。其中,X线片、显微CT/锥形束CT定位法操作简便,临床较为常用;而较为复杂的根管系统,利用数字化导板可建立更精准的开髓通路,减少牙体硬组织不必要的丧失,但数字化导板定位价格较高,临床上并未得到广泛的应用。CEC的洞型包括微创开髓洞型、超保守微创开髓洞型、“Truss”洞型以及切端洞型。CEC洞型与传统开髓洞型的应力分析目前以万能力学试验机加载离体牙、有限元分析法及临床观察为主,大多数学者的研究显示保留较多牙体组织的CEC可提高牙齿的抗折强度,但二者之间的抗折能力仍存在争议,在达到牙髓治疗目的与最大限度保留牙体结构之间如何达到平衡,仍需进一步的探索。  相似文献   
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IntroductionThis study was designed to assess whether a dental caries management protocol combining a single application of 38% silver diamine fluoride (SDF) with comprehensive oral health education will successfully divert high-risk children from dental treatment under dental general anaesthesia (DGA), arrest active caries in primary teeth, and improve parent-reported child oral health–related quality of life (OHRQoL).MethodsChildren aged 2 to 10 years, who attended two public dental agencies in Victoria, Australia, and were unable to tolerate restorative treatments in the clinic setting, elected to participate in either a 38% SDF intervention protocol or, alternatively, referral for DGA. Follow-up examinations were completed at 6 months to assess caries progression, decayed missing filled tooth index, PUFA index (pulpal involvement, ulceration, fistula, abscess), DGA referral rates, and OHRQoL (Early Childhood Oral Health Impact Scale [ECOHIS]).ResultsOf the total sample, 89.5% of children (n = 102) [mean (SD) age, 4.1 (1.0) years] with 401 active carious lesions elected to participate in the 38% SDF protocol; 10.5% (n = 12) of parents opted for referral for treatment under DGA. The proportion of active caries subsequently arrested at follow-up (number of arrested lesions/number of lesions treated) was 0.78 (95% CI, 0.69 to 0.87). There was an 88% reduction in referrals for DGA in eligible children over the 6-month period. The 38% SDF intervention group showed a significant improvement in ECOHIS scores at follow-up (P < .001).DiscussionAdoption of the 38% SDF intervention protocol resulted in a significant reduction in the rate of preventable dental hospitalisations. Most parents opted against referral for DGA. Parent-reported OHRQoL for children improved significantly.  相似文献   
5.
牙外伤是口腔急诊常见的病症之一,及时准确的牙髓活力判断是正确治疗以利维持美学与功能的重要前提条件。文章通过对牙髓活力的生物学基础、牙髓活力测验方法及评价、外伤牙髓受损类型和牙髓活力特点分析,在国际牙外伤临床治疗指南的方向指导下,结合案例和经验,概括外伤牙活力与实施临床治疗方案的关系,为提高牙外伤的临床诊治思维、科学精准和个性化治疗设计提供支持,具有重要的应用价值。  相似文献   
6.
二甲双胍是目前治疗糖尿病的一线药物,除降血糖作用外,其还被发现有促成牙本质分化、促成骨分化、抗肿瘤、抗炎等作用。已有研究表明二甲双胍可以促进根尖周病变组织愈合,其机制可能与二甲双胍激活腺苷酸活化蛋白激酶促进成骨分化与诱导牙髓细胞分化有关。应用二甲双胍辅助治疗的牙周炎患者探诊深度、附着丧失水平以及探诊出血指数等临床指标明显改善,其可能是通过促进牙周膜干细胞的增殖、迁移和成骨分化发挥防治牙周炎的作用。二甲双胍已被证实可抑制肿瘤细胞生长增殖等,在防治口腔肿瘤如口腔鳞状细胞癌中有重要作用。然而,目前大部分的研究仍处于体外和动物试验阶段,二甲双胍防治口腔疾病的具体分子作用机制尚未阐明;临床试验停留在对临床指标的评价方面,需进一步开展大规模、长期、多中心、随机对照的临床试验。  相似文献   
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BackgroundSince the introduction of stemless anatomic total shoulder arthroplasty (TSA), many studies have been published on this specific group of TSA implants. The following study aimed to evaluate clinical and radiological short- to mid-term outcomes of the LIMA SMR stemless anatomical implant.MethodsWe prospectively evaluated the outcome of 53 TSAs in 52 patients, with a mean age of 58.45 years (range 47-78 years) at the time of implantation with a minimum follow-up of 2 years (range 24-47 months). All patients were physically and radiologically examined; the results were documented by the Constant-Murley Score and the Simple Shoulder Value.ResultsSignificant improvements from preoperative to latest follow-up were documented in Constant-Murley Score (29.0-75.84 pts; P < .001), active range of motion (abduction 84.7°-133.2°, flexion 95.3°-146.4°, and external rotation 12.7°-32.4°). The mean Simple Shoulder Value was 82.15% at the last follow-up. There was no complete loosening of the humeral component, but a lowering of bone mineral density (radiolucencies, RLL) was observed in anteroposterior or axially views—radiographs at the humeral component in 10.2% of the cases, most of them on the anteroposterior view at the calcar region. There was no statistical difference in the outcome of the patients with RLL compared with the ones without radiolucencies. Major complications or revisions did not occur.ConclusionThis study provides comparable improvement in functional, radiographic, and subjective mid-term results with other stemless anatomic implants.  相似文献   
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The aim of the study was to compare automated and manually conducted (slice-by-slice) virtual orbital wall reconstruction in terms of PSI design, manufacture, and clinical application for orbital fracture management.Patients with orbital wall fractures were evaluated for the potential for treatment with PSI, based on automated virtual wall reconstruction; these formed the main group. The surgical outcomes of these main-group patients' treatments were compared with those of the control group, which comprised patients randomly selected for this study, each of whom had the same orbital trauma patterns and were also managed with PSI. However, the control group patients were treated using ‘slice-by-slice’ virtual orbital reconstruction.Mean volume differences between the intact and reconstructed orbit were 0.65 ± 0.26 cm3 in the main group (n = 23) and 0.57 ± 0.23 cm3 in the control (n = 27; p = 0.837). In both groups, no cases of implant malposition or enophthalmos were detected after surgery. Orbital shape difference was similar for the main group and the control, at ?3.3 ± 3.5% and 3.25 ± 2.5%, respectively (p = 0.929). Diplopia was diagnosed at the 3-month follow-up in 13.0% of the main group and in 11.1% of the control (p = 0.651). The average times spent on computer-aided design (CAD) procedures, including segmentation, virtual orbital reconstruction, and PSI design, were 36.7 ± 6.9 min in the main group and 72.9 ± 7.7 min in the control group (p < 0.001).Within the limitations of the study it seems that PSI based on automated virtual reconstruction is a relevant alternative treatment option for orbital fractures because of its clinical efficacy that is similar to PSI based on a ‘slice-by-slice’ CAD protocol.  相似文献   
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