不同溶剂的酒石酸酸蚀对黏结强度影响的研究

目的观察用不同溶剂的酒石酸酸蚀牙釉质表面对黏结强度的影响。方法40颗前磨牙随机分为4组,分别用10%的酒石酸水溶液、10%酒石酸乙醇水溶液、10%酒石酸丙酮水溶液及37%磷酸酸蚀(对照组)前磨牙颊面牙釉质表面后,用京津釉质黏合剂黏结舌侧扣。通过电子万能实验机测量记录舌侧扣在轴向拉力作用下脱位的张力强度。结果用37%磷酸酸蚀、10%的酒石酸水溶液酸蚀、10%酒石酸乙醇水溶液酸蚀、10%酒石酸丙酮水溶液酸蚀牙釉质后,京津釉质黏合剂黏结舌侧扣脱位的张力强度分别为(4.12±1.11)MPa、(4.42±1.64)MPa、(2.57±0.75)MPa、(2.65±1.22)MPa,4者间有显著性差异(P<0.01)。结论不同溶剂的酒石酸酸蚀对黏结强度有一定的影响。     

Effects of Osseodensification on Immediate Implant Placement: Retrospective Analysis of 211 Implants

Osseodensification is a new method of bone instrumentation for dental implant placement that preserves bulk bone and increases primary implant stability, and may accelerate the implant rehabilitation treatment period and provide higher success and survival rates than conventional methods. The aim of this retrospective study was to evaluate and discuss results obtained on immediate implant placement with immediate and delayed loading protocols under Osseodensification bone instrumentation. This study included private practice patients that required dental implant rehabilitation, between February 2017 and October 2019. All implants were placed under Osseodensification and had to be in function for at least 12 months to be included on the study. A total of 211 implants were included in the study, with a 98.1% total survival rate (97.9% in the maxilla and 98.5% in the mandible). For immediate implants with immediate load, 99.2% survival rate was achieved, and 100% survival rate for immediate implant placement without immediate load cases. A total of four implants were lost during this period, and all of them were lost within two months after placement. Within the limitations of this study, it can be concluded that Osseodensification bone instrumentation provided similar or better results on survival rates than conventional bone instrumentation.     

酸蚀处理对新型自粘结树脂水门汀粘结强度的影响

目的:评价酸蚀处理对新型自粘结树脂水门汀Unicem与牙本质和牙釉质之间粘结强度的影响。方法:选取新鲜拔除的无龋坏人第三磨牙36个,制备颊侧牙本质粘结面和近、远中牙釉质粘结面,随机分为3组,每组12个牙,分别选用Unicem、磷酸酸蚀配合Unicem和Panavia F(对照组)进行粘结处理,分别测试牙本质、牙釉质粘结强度,并通过扫描电镜观察粘结界面。结果:在牙本质粘结强度上,Unicem组(12.84±2.29 MPa)与Panavia F组(14.93±3.73 MPa)之间无显著性差异(P>0.05),但均显著高于磷酸酸蚀配合Unicem组(9.12±1.54 MPa)(P<0.05);牙釉质粘结强度上,磷酸酸蚀配合Unicem组(17.24±7.62 MPa)和Panavia F组(17.99±3.66 MPa)无显著性差异(P>0.05),但均显著高于Unicem组(6.47±1.54MPa)(P<0.05)。结论:酸蚀处理可以显著提高自粘结树脂水门汀Unicem牙釉质粘结强度,却降低了牙本质粘结效果。     

浙江杭州西湖区儿童龋病发生情况及与父母受教育水平关系

目的 随访调查某地儿童龋病发生情况,并分析患龋率与父母受教育水平关系,为采取针对性预防措施提供参考依据.方法 采用随机整群分层抽样方法,选取2014年3月-2016年6月浙江杭州西湖区6～12岁1 260名学龄儿童为研究对象,检查龋病发生情况,并应用logistic回归分析患龋率与父母受教育水平关系.结果 1 260名...     

血液环境下Biodentine与MTA的颜色稳定性研究

目的 比较牙体牙髓治疗中常用的骨水泥材料Biodentine与三氧化矿物凝聚体(mineral trioxide ag-gregrate,MTA)在与血液接触条件下的颜色稳定性,并探讨其可能的变色原因.方法 制备直径5 mm、高3 mm的Biodentine和MTA圆盘,将每种材料的24个圆盘随机分配到去离子水组和脱纤...     

Rhombohedral Phase Formation in Yttria-Stabilized Zirconia Induced by Dental Technical Tools and Its Impact on Dental Applications

In the study the influence of different dental technical tools on the surface temperature and phase composition of fixed dental prostheses (FDPs) made of yttria-partially stabilized zirconia polycrystals (3Y-/4Y-/5Y-PSZ) was investigated. FDPs were fabricated by using computer-aided manufacturing (CAM). The FDPs were treated with a contra-angle handpiece equipped with different burs and polishers. The resulting surface temperatures were measured with a thermographic camera, and the resulting phase transformations were investigated by X-ray diffraction and quantified by Rietveld refinement. Processing with burs resulted in no phase transformation, but a preferred orientation shift. Using coarse polisher induced a phase transformation to the rhombohedral phase, while fine polishers produced no relevant phase transformations and no preferred orientation shift. Compared to the monoclinic phase (ca. 9% theoretical volume increase), which is associated with low-temperature degradation (LTD), the rhombohedral phase is much more voluminous (ca. 15% theoretical volume increase) and distorted and, therefore, has a greater degradation potential.     

Intrusion of overerupted molars with temporary anchorage devices before prosthetic reconstruction: A case report

Extraction of teeth without adequate prosthetic rehabilitation frequently can lead to overeruption of opposing teeth, which may cause occlusal disturbances and complicate dental restoration. Equilibration with consequent need of endodontic treatment, surgical intrusion or extraction are often indicated as a remedy in such cases. The article proposes a method of orthodontic intrusion with the use of temporary anchorage devices as a predictable and less invasive option. Important clinical aspects of molar intrusion with respect to surrounding anatomical structures are also discussed.     

Influence of Xenogeneic and Alloplastic Carriers for Bone Augmentation on Human Unrestricted Somatic Stem Cells

Alloplastic and xenogeneic bone grafting materials are frequently used for bone augmentation. The effect of these materials on precursor cells for bone augmentation is yet to be determined. The aim of this study was to ascertain, in vitro, how augmentation materials influence the growth rates and viability of human unrestricted somatic stem cells. The biocompatibility of two xenogeneic and one alloplastic bone graft was tested using human unrestricted somatic stem cells (USSCs). Proliferation, growth, survival and attachment of unrestricted somatic stem cells were monitored after 24 h, 48 h and 7 days. Furthermore, cell shape and morphology were evaluated by SEM. Scaffolds were assessed for their physical properties by Micro-CT imaging. USSCs showed distinct proliferation on the different carriers. Greatest proliferation was observed on the xenogeneic carriers along with improved viability of the cells. Pore sizes of the scaffolds varied significantly, with the xenogeneic materials providing greater pore sizes than the synthetic inorganic material. Unrestricted somatic stem cells in combination with a bovine collagenous bone block seem to be very compatible. A scaffold’s surface morphology, pore size and bioactive characteristics influence the proliferation, attachment and viability of USSCs.     

运用Demirjian法测量替牙早期前牙反合患者的牙龄研究

目的 评估Demirjian法测定天津地区儿童的牙龄的适用性.方法 运用Demirjian法测定天津地区替牙早期前牙反合患者治疗期间牙龄的变化量,并与实际年龄的变化量进行比较分析.结果 Demirjian法测定的牙龄变化量无论男性组还是女性组与实际年龄变化量均无显著性差异.结论 Demirjian法适用于中国天津地区替牙前期前牙反合患者牙龄的测定.     

肝移植术后早期口腔并发症及深部真菌感染的预防

目的:观察研究口腔内局部联合用药预防肝移植术后早期口腔感染及深部真菌感染的临床效果。方法:将162例肝移植术后患者随机分为观察组A(57例)、观察组B(62例)和对照组(43例),观察组A采用3%碳酸氢钠溶液和0.1%西吡氯铵含漱液局部联合进行口腔干预,观察组B采用5×104U/mL制霉菌素水混悬液和0.1%西吡氯铵含漱液局部联合进行口腔干预,对照组常规采用生理盐水进行口腔干预。观察并记录患者术后口腔并发症,并进行血浆(1-3)-β-D葡聚糖水平检测。结果:3组口腔并发症和(1-3)-β-D葡聚糖水平差异均有统计学意义(P<0.05或P<0.01),其中观察组A与对照组牙龈红肿发生率组间差异有统计学意义,观察组B与对照组口腔溃疡、霉菌感染发生率差异有统计学意义,观察组A和观察组B之间口腔并发症和(1-3)-β-D葡聚糖水平差异无统计学意义(P>0.05)。结论:采用0.1%西吡氯铵含漱液分别与3%碳酸氢钠溶液或5×104U/mL制霉菌素水混悬液联合应用进行口腔干预对预防肝移植术后早期口腔并发症及深部真菌感染有临床意义。