An <i>in Vitro</i>Study of Microleakage Comparing Total-Etch with Bonding Resin and Self-Etch Adhesive Luting Cements for All-Ceramic Crowns

Aim: The aim of the study was to assess the dye leakage present following cementation of all-ceramic crowns with 7 currently used cements to compare total-etch (TE) with dentine bonding agent (DBA) and self-etch (SE) systems. Methods: Forty-two Authentic? crowns were fabricated and cemented onto extracted human teeth using 7 currently available cements (2 two-stage adhesives (TE + DBA): Panavia 21 Kuraray;Paracore, Coltene Whaledent and 5 all-in-one adhesives (SE): MaxCem Kerr;Panavia F2.0 Kuraray;RelyX Unicem 3MEspe;seT SDI). Following storage in water and thermal cycling, the teeth were exposed to dye, sectioned and examined under confocal microscopy. Leakage was determined by two blinded examiners and scoring was carried out on a scale of 0 - 8 per tooth (0 = no leakage, 8 complete leakage across the section). One overall reading was obtained per tooth with 6 teeth per material. Results: The results showed a wide range of scores between the different cements. Only a few specimens which used TE + DBA showed slight marginal leakage: Paracore (mean score 0 ± 0) and Panavia 21 (0.3 ± 0.5). The majority of specimens using SE showed leakage: RelyX Unicem (0.8 ± 0.8), SmartCem (1.7 ± 2.1), MaxCem (3.2 ± 1.7), Panavia F2.0 (4.5 ± 2.4) then seT (5.2 ± 2.5). Statistical analysis was carried out showing that Paracore and Panavia 21 were significantly less prone to leakage than MaxCem, (P = 0.002) and seT (P < 0.001). Conclusion: In conclusion, the choice of luting cement is important in reducing dye leakage. This study strongly favours the use of a TE with separate adhesive system placed prior to the composite luting resin.

Influence of Abutment Material on the Stress of Implant-supported All-ceramic Single Crown

In order to investigate the influence of abutment material on the stress of implant-supported all-ceramic single crown, a 3D finite element model of implant-supported mandibular first premolar was computed by COSMOS/M 2.85 software. Alumina, zirconia, and titanium were used as abutment materials respectively. Vertical 600 N and horizontal 225 N load was applied on the occlusal surface. The results show that the stress distribution of implant-supported single crown was similar for different abutment materials. Maximum stresses within the crown were higher when titanium abutment was used. Maximum stress of titanium abutment was lower than that of ceramic abutment. Within the screw and fixture, maximum stresses had no difference under vertical loading but higher as titanium abutment was used under horizontal loading. There was no difference of maximum stress within the bone when different abutment materials were used. The present findings indicate that the abutment material had no influence on the stress distribution of implant-supported all- ceramic single crown but maximum stress when the titanium abutment was lower than that of ceramic abutment.

Interfacial engineering through lead binding using crown ethers in perovskite solar cells

In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-guest complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications.

Influence of Different Luting Agents on the Stress Distributions of Implant-supported All-ceramic Single Crown

The purpose of this study was to investigate the influence of different luting agents on the stress distribution within the crown, abutment and peri-implant bone of implant-supported all-ceramic single crown. A three-dimensional finite element model of an implant-supported single crown for the first premolar of mandible was created by COSMOS 2.85. Resin-modified glass ionomer and two different resin adhesives were used to cement the crown and abutment. Vertical 600 N and horizontal 225 N loads were applied to stimulate the condition of chewing. The stress distributions within the all-ceramic crown, abutment and peri-implant bone were analyzed. The experimental results show that the stress distributions of all-ceramic crown, abutment, implant and peri-implant bone were similar when different luting agents were used. The result of present study indicated that luting agents had no influence on the stress distributions of implant-supported all-ceramic single crown.

Developing nonlinear additive tree crown width models based on decomposed competition index and tree variables

Crown development is closely related to the biomass and growth rate of the tree and its width(CW)is an important covariable in growth and yield models and in forest management.To date,various CW models have been proposed.However,limited studies have explicitly focused on additive and inherent correlation of crown components and total CW as well as the influence of competition on crown radius from the corresponding direction.In this study,two model systems were used,i.e.,aggregation method system(AMS)and disaggregation method system(DMS),to develop crown width additive model systems.For calculating spatially explicit competition index(CI),four neighbor tree selection methods were evaluated.CI was decomposed into four cardinal directions and added into the model systems.Results show that the power model form was more proper for our data to fit CW growth.For each crown radius and total CW,height to the diameter at breast height(HDR)and basal area of trees larger than the subject tree(BAL)significantly contributed to the increase of prediction accuracy.The 3-m fixed radius was optimal among the four neighborhoods selection ways.After adding decomposed competition Hegyi index into model systems AMS and DMS,the prediction accuracy improved.Of the model systems evaluated,AMS based on decomposed CI provided the best performance as well as the inherent correlation and additivity properties.Our study highlighted the importance of decomposed CI in tree CW modelling for additive model systems.This study focused on methodology and could be applied to other species or stands.

The Effect of Alumina Content on Fracture Property of All-ceramics Zirconia

The purpose of the present study was to evaluate the effect ofA1203 content on the fracture property of all-ceramics ZrO2. To improve the all-ceramics ZrO2 restoration mechanics properity ,96 samples containing 0,5,10 and 15 wt% of A1203 particles were prepared by cold isostatic pressing （200 MPa） and 1 550 ℃ sintered .The phase was analyzed by X-ray diffraction analysis and the bulk densities of the samples were made using Archimedes principle. Samples were randomly divided into four groups. In each group, 24 specimens were prepared so that the angle between notch and specimen＇s long axis is 90° and 60°. Notch depths were 1 mm for all samples. Samples were loaded with three-point bending method. 90° cut samples were used to measure fracture toughness while 60°cut samples were used to observe fracture curve by taking points on the fracture extension path under microscope, plotting points on coordinates, generating fitting curve by software ＂Origin＂, and analyzing the microstructure of the specimen fracture surfaces by scanning electron microscopy （SEM）.The results show that the increment ofA1203 has insignificant effect on the densification of all-ceramic ZrO2.XRD analysis shows that the specimen is comprised of t-ZrO2 and a- A1203 before fracture while fracture surface is m-ZrO2, t-ZrO2 and a-A1203. ZrO2 containing 10% A1203 has the optimum mechanical properties and unconspicuous crack propagation and distribution. The observations may provide a reference for the materials selection, shaoe design, and production orocess of all-ceramic crown and bridge.

Insightful Understanding of the Role of the Mechanical Properties in Defining the Reliability of All-Ceramic Dental Restorations: A Review

Since the last two decades, restorative dentistry has been witnessing an increased acceptance of the use of the well-known all-ceramic materials for the fabrication of single dental restorations, such as inlays, onlays, crowns, anterior and posterior fixed partial dentures (PFPDs). These restorations certainly offer the potential for better biocompatibility coupled with superior aesthetic qualities, especially when compared with the conventional prostheses made from porcelain that is fused with metal ceramic restorations. However, brittleness and extreme sensitivity of all-ceramic materials to micro-like defects or cracks that are inherently present, or may grow, in their microstructure during different laboratory fabrication steps, during necessary clinical adjustments, or from post-placement chewing activity, remain major shortcomings of these dental restorations. In fact, many researchers are of the opinion that the improved mechanical properties can significantly improve the lifetime of all-ceramic restorations and result in enhanced reliability. Therefore, efforts of researchers, as well as manufacturers, have been directed towards the improvement of the mechanical properties in order to overcome such limitations. This article reviews the characterization of the most important mechanical properties that can delineate the behavior of all-ceramic dental materials upon loading. These include fracture mechanics, the brittle nature of ceramics, the relationship between microstructural features and fracture behavior, sources of cracks and flaws that may initiate a fracture and the effect of different fabrication procedures and/or clinical adjustments on the mechanical behavior of dental ceramics are also reviewed and discussed.

Prediction of tree crown width in natural mixed forests using deep learning algorithm

Crown width(CW)is one of the most important tree metrics,but obtaining CW data is laborious and timeconsuming,particularly in natural forests.The Deep Learning(DL)algorithm has been proposed as an alternative to traditional regression,but its performance in predicting CW in natural mixed forests is unclear.The aims of this study were to develop DL models for predicting tree CW of natural spruce-fir-broadleaf mixed forests in northeastern China,to analyse the contribution of tree size,tree species,site quality,stand structure,and competition to tree CW prediction,and to compare DL models with nonlinear mixed effects(NLME)models for their reliability.An amount of total 10,086 individual trees in 192 subplots were employed in this study.The results indicated that all deep neural network(DNN)models were free of overfitting and statistically stable within 10-fold cross-validation,and the best DNN model could explain 69%of the CW variation with no significant heteroskedasticity.In addition to diameter at breast height,stand structure,tree species,and competition showed significant effects on CW.The NLME model(R^(2)=0.63)outperformed the DNN model(R^(2)=0.54)in predicting CW when the six input variables were consistent,but the results were the opposite when the DNN model(R^(2)=0.69)included all 22 input variables.These results demonstrated the great potential of DL in tree CW prediction.

Replacement of Unesthetic Posterior Metal Crowns with Monolithic Zirconia Crowns: A Case Report

Advances in metal-free materials and the popularization of Computer-Aided Design and Manufacturing (CAD/CAM) have led to the wide clinical use of all-ceramic crowns for esthetic restorations. A 72-year-old woman presented to our hospital with unesthetic restorations on the right upper and lower posterior teeth. Intraoral examination revealed poorly fitting metal crown margins. Defective prostheses were removed, and provisional restorations were provided to stabilize the mandibular position. Optical impressions and the maxillomandibular relationship were recorded using an intraoral scanner, and monolithic zirconia crowns were fabricated using CAD/CAM technology for complete veneer crown restorative treatment. Occlusal examination revealed an improvement in occlusal force distribution at initial examination (right side: 33.5%, left side: 66.5%) after placement of the zirconia crowns (right side: 54.9%, left side: 45.1%). Occlusal force and occlusal force distribution area also showed an increasing trend. The Oral Health Impact Profile short form (OHIP-14) score decreased from 7 points at initial examination to 0 points after prosthodontic treatment. Appropriate diagnosis and treatment planning contributed to the increased occlusal force and balanced occlusal force distribution. Therefore, the present case indicates the potential of monolithic zirconia crowns to achieve both esthetic and stable functional outcomes.

Changes in concentrations and transcripts of plant hormones in wheat seedling roots in response to Fusarium crown rot

Fusarium crown rot(FCR) is a soilborne disease causing severe yield losses in many wheat-growing areas of the world. Diseased plants show browning and necrosis of roots and stems causing white heads at maturity. Little is known about the molecular processes employed by wheat roots to respond to the disease. We characterized morphological, transcriptional and hormonal changes in wheat seedling roots following challenge with Fusarium pseudograminearum(Fp), the main pathogen of FCR. The pathogen inhibited root development to various extents depending on plants' resistance level. Many genes responsive to FCR infection in wheat roots were enriched in plant hormone pathways. The contents of compounds involved in biosynthesis and metabolism of jasmonic acid, salicylic acid, cytokinin and auxin were drastically changed in roots at five days post-inoculation. Presoaking seeds in methyl jasmonate for 24 h promoted FCR resistance, whereas presoaking with cytokinin 6-benzylaminopurine made plants more susceptible. Overexpression of TaOPR3, a gene involved in jasmonic acid biosynthesis, enhanced plant resistance as well as root and shoot growth during infection.

Assessment of Cork Oak Decline Using Digital Multispectral Imagery in Relation with in Situ Crown Condition

Cork oak in Maamora forest is experiencing the dieback phenomenon. The evaluation of the latter in this forest has gained the importance over time and with the solicitation of managers to objectify its phytosanitary situation. Aiming at prioritizing management actions, remote sensing seems to be an effective tool to inquire about stands’ health conditions and their evolution. To this end, this study aims at mapping and validating health status of cork oak stands in Maamora. Sentinel 2 images in 2015 and 2020 were processed to calculate the differential normalized difference water index (NDWI), revealing vegetation moisture variation caused by drought. A statistical method based on thresholds was used to map cork oak dieback stands, those with no changes and those recovered. Results have shown that 54.63% of cork oak in Maamora forest have not changed in terms of phytosanitary situation between 2015 and 2020, 31.10% of oak stands are afflicted by a slight decline and 12.97% by a severe decline. Areas with slight or strong recovery remain minimal and represent 1.04% and 0.25% respectively. Ground data indicated that the map generated displayed a good distinction between stands severely and slightly declined with a global accuracy of 66.66%. Therefore, further research elaborating an advanced vegetation index reflecting the various factors of dieback would be of much importance.

Li^(+)-ion bound crown ether functionalization enables dual promotion of dynamics and thermodynamics for ambient ammonia synthesis

Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous efforts devoted to electrocatalysts themselves,they still fail to tackle the above two challenges simultaneously.Herein,we employ a heterogeneous catalyst adlayer-composed of crown ethers associated with Li^(+)ions-to achieve the dual promotion of dynamics and thermodynamics for ambient ammonia synthesis.Dynamically,the bound Li^(+)ions interact with the strong quadrupole moment of nitrogen,and trigger considerable reactant flux toward the catalyst.Thermodynamically,Li^(+)associated with the oxygen of crown ether achieves a higher density of states at the Fermi level for the catalyst,enabling effortless electron transfer from the catalysts to nitrogen and thus greatly reducing the activation barrier.As expected,the proof-of-concept system achieves an ammonia yield rate of 168.5μg h^(-1)mg^(-1)and a Faradaic efficiency of 75.3%at-0.3 V vs.RHE.This system-level approach opens up pathways for tackling the two key challenges that have limited the field of ammonia synthesis.

Wave Force on the Crown Wall of Rubble Mound Breakwaters at Intermediate Depths

Rubble mound breakwaters with a crown wall are a common coastal engineering structure.The wave force on crown walls is an important parameter for the practice engineering design.Particularly,the wave force on crown walls under intermediate depths has been studied through physical model tests and numerical simulations.In this study,a three-dimensional numerical wave flume was developed to investigate monochromatic wave interactions in a rubble mound breakwater with a crown wall.Armor blocks were modeled in detail.The Navier-Stokes equations for two-phase incompressible flows,combined with shear stress transport k-ωturbulence model and volume of fluid method for tracking the free surface,were solved.A set of laboratory experiments were performed to validate the adopted model.Subsequently,a series of numerical simulations were implemented to examine the impacts of different hydrodynamic parameters(including wave height,incident wave period,and water depth)and the berm width on the wave force of the crown wall.Finally,a comparison of the experimental results and Martin method shows that the latter method is not suitable for this experimental scope.New empirical formulas are proposed to predict the wave force on crown walls under intermediate depth.The results can provide a basis for the design of crown wall of rubble mound breakwaters at intermediate depths.

Third-Order Nonlinear Optical Responses of Bis(15-crown-5)-stilbenes Binding to One-or Two-Alkali Metal Cation(Li^(+),Na^(+)and K^(+))

Bis(15-crown-5)-stilbenes containing crown ether parts have been widely used in a variety of chemical applications,such as cation detectors,because of their ability to selectively bind to alkali metal cations,Bis(15-crown-5)-stilbenes and its derivatives with complexation of one-or two-alkali metal cation(Li^(+),Na^(+)and K^(+))have been theoretically investigat-ed by quantum chemistry methods.The coordination of alkali cations results in partial shrinkage of crown ethers,which directly affected natural distribution analysis charges and molecular orbital energy levels.The number of alkali metal ions has significant effects on absorption spectra and mean second hyperpolarizability.When one alkali metal ion was added to the anticonformer of bis(15-crown-5)-stilbene,the absorption spectra were obvious-ly redshifted and the mean second hyperpolarizability values were slightly increased;while two alkali metal ions were added to bis(15-crown-5)-stilbene,the absorption spectra were ob-viously blue shifted and the mean second hyperpolarizability values decreased.On the other hand,as the radius of the alkali ions increased,the mean second hyperpolarizability values of the compounds increased gradually.It is indicated that the mean second hyperpolarizability value is sensitive to the number and radius of the alkali metal cations,thus the third order nonlinear optical response can be used as a signal to detect the number and type of alkali met-al ions.

生物活性陶瓷iRoot BP Plus^(■)在儿童年轻恒前牙复杂冠折牙髓切断术中的应用

目的:观察生物活性陶瓷材料iRoot BP Plus^(■)(Innovative BioCeramix Inc,Vancouver,BC,Canada)在儿童年轻恒前牙复杂冠折牙髓切断术中的应用,并对其预后进行分析,为该术式的更广泛应用提供临床参考。方法:收集2017年3月至2022年9月因恒前牙复杂冠折就诊于北京大学口腔医院急诊科,行以生物活性陶瓷iRoot BP Plus^(■)为盖髓剂的牙髓切断术患者。根据患者术前根尖片和初诊病历显示为年轻恒牙者,纳入97颗年轻恒牙进行研究。收集患者初诊及复查时的临床及影像学检查资料,临床检查包括根尖孔形成情况、松动度、牙冠颜色、牙髓活力测试(冷测)、有无脓肿和瘘管,影像学检查包括根周膜连续性、根尖周低密度影像、复诊时盖髓剂下方牙本质桥形成情况、髓腔及根管钙化情况,并对上述结果进行分析。结果:最终纳入有复诊记录的64例患者共75颗患牙,其中男性37例(57.8%),女性27例(42.2%),就诊时平均年龄为9.1岁,平均随访时长19.3个月。采用iRoot BP Plus^(■)盖髓的牙髓切断术后6个月成功率为96.0%,术后1年成功率为94.7%。术后复查2年以上者共23例,累计失败6例。成功率在患牙就诊时距外伤的时间是否超过24 h组中(P=0.61)以及是否松动组中(P=0.28)的差异无统计学意义。结论:对无移位性损伤的年轻恒牙复杂冠折患牙,采用iRoot BP Plus^(■)盖髓的牙髓切断术1年成功率很高,该术式具备广泛推广价值。

金冠豆角籽粒淀粉组成及性质研究

为了明确金冠豆角淀粉的基本性质,本文以提取盐溶蛋白后剩余的金冠豆角籽粒豆渣为原料,采用水提法提取淀粉,观察淀粉颗粒形态,测定其组成、粒径、理化性质及体外抗消化特性。结果表明,金冠豆角籽粒淀粉中直链淀粉和支链淀粉的含量分别为47.39%和52.07%,淀粉的颗粒形态与豌豆淀粉类似,呈卵圆形或球型,颗粒表面光滑完整,粒径为75.10μm。金冠豆角籽粒淀粉的峰值粘度(212.20 RVU)、衰减值(68.50 RVU)较低,但回生值(96.80 RVU)高于玉米淀粉;金冠豆角籽粒淀粉糊化的起始温度(T_(0))、峰值温度(T_(p))显著高于豌豆淀粉(P<0.05)。金冠豆角籽粒淀粉的凝沉值在90 min时接近80%,凝沉速度显著高于玉米淀粉,透光率介于豌豆淀粉和玉米淀粉之间,持水性(WHC)和持油性(OHC)值分别为1.08和1.00 g/g,凝胶硬度小,属于易凝沉淀粉,其抗性淀粉(RS)含量为68.43%,高于玉米淀粉和豌豆淀粉(P<0.05),具有良好的抗消化特性。

种衣剂防治小麦茎基腐病效果的评价

茎基腐病已成为黄淮小麦主产区最具破坏性的土传病害之一,对我国粮食安全供给构成严重威胁。目前抗茎基腐病主栽品种稀少,生产上主要依赖于化学农药措施。药剂拌种可以有效防治茎基腐病。综合评价现有的种衣剂对小麦茎基腐病的防治及增产效果,以期为合理用药提供依据。采取高感茎基腐病小麦品种郑麦1354为研究对象,播种前种子包衣晾干,利用高致病力茎基腐病菌株PY20-20培养小米菌谷,连续2个小麦生长季利用进行人工接种病圃,包衣种子和接种菌谷等重量混合播种,分别于小麦拔节期和乳熟期记载处理小区植株发病情况,调查9种种衣剂处理后不同生育期的病情指数(disease index,DI),成熟收获后测定小区实际产量,结合小麦产量相关性状,比较种衣剂防病增产作用。结果表明:种衣剂处理后拔节期茎基腐病DI值均小于1.0,显著小于空白对照(5.07),防治效果为85.09%~100%,其中33 g·L^(-1)咯菌·噻虫胺、9%苯甲·吡虫啉和35 g·L^(-1)精甲霜灵·咯菌腈的防效达到为97%~100%。在乳熟期,种衣剂处理后茎基腐病DI平均值低于15,显著小于空白对照(81.55),其中35 g·L^(-1)精甲霜灵·咯菌腈和9%苯甲·吡虫啉防效较好,平均防效分别达到92%和95%,而且分别增产39.62%和36.31%。综合而言,采用种衣剂35 g·L^(-1)精甲霜灵·咯菌腈和9%苯甲·吡虫啉防治小麦茎基腐病效果好且增产效果显著,具有较好的应用前景。

前牙高透氧化锆全瓷冠修复单颗前牙缺损的美学效果分析

目的:探究高透氧化锆全瓷冠修复单颗前牙缺损的美学效果。方法:选取2018年1月-2020年10月笔者医院收治的单颗前牙缺损患者80例(共80颗患牙),按随机数表法分为观察组(高透氧化锆全瓷冠修复)和对照组(钴铬烤瓷冠修复),每组40例(40颗患牙),比较两组的修复效果,修复前、修复后1个月的牙周指标及龈沟液指标[碱性磷酸酶(Alkaline phosphatase,ALP)、白介素6(Interleukin-6,IL-6)、白介素8(Interleukin-8,IL-8)]水平,对比两组修复后1年的满意度及并发症发生情况。结果:修复后1年,两组颜色对比、边缘着色、解剖外形、边缘密合度、龋齿等修复效果评估观察组均高于对照组(P<0.05)。修复后1个月,两组牙周探诊深度、菌斑指数、出血指数均升高,但观察组低于对照组(均P<0.05);两组龈沟液ALP、IL-6、IL-8水平均降低,且观察组均低于对照组(均P<0.05)。修复后1年,观察组修复总满意度高于对照组(P<0.05);修复后1年期间,两组均未发生牙体腐蚀,疼痛、牙龈炎、根折发生率差异无统计学意义,观察组并发症总发生率低于对照组(P<0.05)。结论:采用高透氧化锆全瓷冠修复单颗前牙缺损的美学效果较好,可减轻牙周组织炎症,值得临床推广应用。

二氧化锆全瓷冠修复前牙的效果及对局部炎症状态的影响

目的:探究及观察二氧化锆全瓷冠修复前牙的效果及对局部炎症状态的影响。方法:选取2019年1月—2021年1月深圳市龙岗区妇幼保健院口腔科的100例需进行前牙冠修复的患者为研究对象,根据随机数字表法分为对照组(镍铬合金烤瓷冠组)和观察组(二氧化锆全瓷冠组),每组50例。比较两组的修复效果(颜色匹配度、完整度及边缘密合度)、不良情况发生率、局部炎症状态指标[龈沟液炎症因子白介素-1β(IL-1β)及白介素-6(IL-6)、炎症介质前列腺素E2(PGE2)]、炎症趋化因子[调节活化正常T细胞表达和分泌因子(RANTES)]、患者满意度。结果:观察组的颜色匹配度、完整度及边缘密合度均显著优于对照组,不良情况发生率显著低于对照组,差异均有统计学意义(P<0.05)。治疗前,两组的局部炎症状态指标比较,差异均无统计学意义(P>0.05);治疗后3、6个月,观察组的局部炎症状态指标均显著优于对照组,患者满意度显著高于对照组,差异均有统计学意义(P<0.05)。结论:二氧化锆全瓷冠修复前牙的效果较好,且可有效控制患者的局部炎症状态,更受患者认可。

氧化锆全冠的临床应用原则及新进展

氧化锆全冠在口腔修复领域得到了广泛的应用。传统氧化锆机械性能佳,但半透性较差,透明氧化锆的出现大大提高了氧化锆的美学性能。但在临床中,应对影响全锆冠美学修复效果的因素进行综合考量,选择最合适的全锆冠修复体,同时临床医师需要根据患者实际情况合理设计牙体预备量以及预备方式。在氧化锆的临床粘接过程中,要对基牙和修复体做好表面处理,选择合适的粘接剂以获得良好的粘接强度和美观性。