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Non-Thermal Atmospheric Plasma:Can it Be Taken as a Common Solution for the Surface Treatment of Dental Materials?

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Plasma Science and Technology 2016年第4期18卷 417-423页

作者： Emre SEKER Mehmet Ali KILICARSLAN Serdar POLAT Emre OZKIR Suat PAT department of prosthodontics Faculty of DentistryEskisehir Osmangazi University department of prosthodontics Faculty of DentistryAnkara University department of prosthodontics Faculty of DentistryGazi University department of prosthodontics Faculty of DentistryAfyon Kocatepe University Faculty of Art and Science Eskisehir Osmangazi University

This study aimed to evaluate the surface roughness and wetting properties of various dental prosthetic materials after different durations of non-thermal atmospheric plasma（NTAP）*** hundred and sixty discs of titanium（Ti）（n：40）,cobalt chromium（Co-Cr）（n：40）,yttrium stabilized tetragonal zirconia polycrystals（Y-TZP）（n：40）and polymethylmethacrylate（PMMA）（n：40）materials were machined and smoothed with silicon carbide *** surface roughness was evaluated in a control group and in groups with different plasma exposure times [1-3-5 s].The average surface roughness（Ra）and contact angle（CA）measurements were recorded via an atomic force microscope（AFM）and tensiometer,*** changes were examined with a scanning electron microscope（SEM）.Data were analyzed with two-way analysis of variance（ANOVA）and the Tukey HSD test α=0.05）.According to the results,the NTAP surface treatment significantly affected the roughness and wettability properties（P 〈 0.05）.SEM images reveal that more grooves were present in the NTAP *** an increase in the NTAP application time,an apparent increment was observed for Ra,except in the PMMA group,and a remarkable reduction in CA was observed in all *** is concluded that the NTAP technology could enhance the roughening and wetting performance of various dental materials.

关键词： dental material atmospheric plasma surface treatment roughness contact angle

Influence of acrylamide monomer addition to the acrylic denture-base resins on mechanical and physical properties

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International Journal of Oral Science 2013年第4期5卷 229-235页

作者： Elif Aydogan Ayaz Rukiye Durkan department of prosthodontics Faculty of DentistryKaradeniz Technical University

The aim of the study was to evaluate the effect of adding acrylamide monomer （AAm） on the characterization, flexural strength, flexural modulus and thermal degradation temperature of poly（methyl methacrylate）（PMMA） denture-base resins. Specimens （n= 10） were fabricated from a conventional heat-activated QC-20 （Qc-） and a microwave heat-activated Acron MC （Ac-） PMMA resins. Powder/ liquid ratio followed the manufacturer＇s instructions for the control groups （Qc-c and Ac-c） and for the copolymer groups, the resins were prepared with 5% （-5）, 10% （- 10）, 15% （- 15） and 20% （-20） acrylamide contents, according to the molecular weight ratio, respectively. The flexural strength and flexural modulus were measured by a three-point bending test. The data obtained were statistically analyzed by Kruskal-Wallis test （a=O.05） to determine significant differences between the groups, The chemical structures of the resins were characterized by the nuclear magnetic resonance spectroscopy. Thermal stabilities were determined by thermogravimetric analysis （TGA） with a heating rate of 10 ~***-1 from 35 ~C to 600 ~C. Control groups from both acrylic resins showed the lowest flexural strength values. Qc-15 showed significant increase in the flexural strength when compared to Qc-c （P〈O.01）. Ac-10 and Ac-15 showed significance when compared to Ac-c （P〈O.01）. Acrylamide incorporation increased the elastic modulus in Qc-10, Qc-15 and Qc-20 when compared to Qc-c （P〈0.01）. Also significant increase was observed in Ac-10, Ac-15 and Ac-20 copolymer groups when compared to Ac-c （P〈0.01）. According to the 1H-nuclear magnetic resonance （NMR） results, acrylamide copolymerization was confirmed in the experimental groups. TGA results showed that the thermal stability of PMMA is increased by the insertion of AAm.

关键词： acrylamide denture resin nuclear magnetic resonance poly(methyl methacrylate) thermogravimetric analysis three-point bending test

Tooth wear against ceramic crowns in posterior region: a systematic literature review

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International Journal of Oral Science 2013年第4期5卷 183-190页

作者： Rim Hmaidouch Paul Weigl department of prosthodontics and Geriatric dentistry Johann Wolfgang Goethe University

The objective of this systematic review was to assess tooth wear against ceramic crowns in posterior region in vitro and in vivo. An electronic PubMed search was conducted to identify studies on tooth wear against ceramic crowns in posterior region. The selected studies were analyzed in regard to type of crowns, natural antagonist, measuring protocol and outcome. From a yield of 1 000 titles, 43 articles were selected for full-text analysis; finally, no in vitro and only five in vivo studies met the inclusion criteria. As there is heterogeneity in design, used measuring method, ceramics and analysis-form, a meta-analysis was not possible. Results of these studies are very controversial which makes a scientifically valid comparison impossible. This review indicated that some all-ceramic crowns are as wear friendly as metal-ceramic crowns. Up to now, it has been impossible to associate tooth wear with any specific causal agent. The role of ceramic surface treatment that might be responsible for the changing in rate of tooth wear seems undetermined as yet through clinical trials. The literature reveals that studies on this topic are subject to a substantial amount of bias. Therefore, additional clinical studies, properly designed to diminish bias, are warranted.

关键词： all-ceramic crowns tooth wear

Electrochemical behavior of dental implant system before and after clinical use

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中国有色金属学会会刊：英文版 2009年第4期19卷 846-851页

作者： Chae-Heon CHUNG Hee-Jung KIM Yong-Tae JEONG Mee-Kyoung SON Yong-Hoon JEONG Han-Cheol CHOE department of prosthodontics College of DentistryChosun University department of Dental Materials & Research Center of Nano-Interface Activation for Biomaterials College of DentistryChosun University

Electrochemical behavior of dental implant system before and after clinical use(in vivo and in vitro) was researched by using abutment and titanium *** simulate an oral environment,the samples of clinically used and non-used implant systems as a working electrode were exposed to artificial saliva at(36.5±1) ℃.Electrochemical tests were carried out using a *** electrochemical test,the corrosion morphology of each sample was investigated by FE-SEM and *** corrosion potential and pitting potential of clinically used implant system are lower than those of non-used implant system,and clinically used implant system exhibits a lower range of passivation,indicating a less degree of inherent resistance against chloride *** polarization resistance decreases in the case of clinically used implant system,whereas,Rp for clinically non-used implant system increases compared with clinically used implant system.

关键词：电化学行为种植制度临床应用使用制度临床使用电化学测试夹具系统腐蚀形态

Surface roughness of zirconia for full-contour crowns after clinically simulated grinding and polishing

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International Journal of Oral Science 2014年第4期6卷 241-246页

作者： Rim Hmaidouch Wolf-Dieter Mller Hans-Christoph Lauer Paul Weigl department of prosthodontics and Geriatric dentistry Faculty of Oral and Dental Medicine at Johann Wolfgang Goethe-University department of prosthodontics and Geriatric dentistry University of Medicine Charite department of Postgraduate Education Faculty of Oral and Dental Medicine at Johann Wolfgang Goethe-University

The aim of this study was to evaluate the effect of controlled intraoral grinding and polishing on the roughness of full-contour zirconia compared to classical veneered zirconia. Thirty bar-shaped zirconia specimens were fabricated and divided into two groups（n515）. Fifteen specimens（group 1） were glazed and 15 specimens（group 2） were veneered with feldspathic ceramic and then glazed. Prior to grinding,maximum roughness depth（Rmax） values were measured using a profilometer, 5 times per specimen. Simulated clinical grinding and polishing were performed on the specimens under water coolant for 15 s and 2 N pressure. For grinding, NTI diamonds burs with grain sizes of 20 mm, 10 mm, and 7.5 mm were used sequentially. The ground surfaces were polished using NTI kits with coarse, medium and fine polishers. After each step, Rmaxvalues were determined. Differences between groups were examined using one-way analysis of variance（ANOVA）. The roughness of group 1 was significantly lower than that of group 2. The roughness increased significantly after coarse grinding in both groups. The results after glazing were similar to those obtained after fine grinding for non-veneered zirconia. However, fine-ground veneered zirconia had significantly higher roughness than venerred, glazed zirconia. No significant difference was found between fine-polished and glazed zirconia, but after the fine polishing of veneered zirconia, the roughness was significantly higher than after *** can be concluded that for full-contour zirconia, fewer defects and lower roughness values resulted after grinding and polishing compared to veneered zirconia. After polishing zirconia, lower roughness values were achieved compared to glazing; more interesting was that the grinding of glazed zirconia using the NTI three-step system could deliver smooth surfaces comparable to untreated glazed zirconia surfaces.

关键词： full-contour zirconia grinding polishing roughness veneering porcelain

New Mini Dental Implant Attachments versus O-ring Attachment after Cyclic Aging: Analysis of Retention Strength and Gap Space

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2017年第3期37卷 419-424页

作者： Abdalbseet A Fatalla 宋珂曹颖光 department of prosthodontics and Implantology Tongji Hospital Tongji Medical College Huazhong University of Science and Technology department of prosthodontics College of Dentistry University of Baghdad

Overdenture as a treatment modality for both partially and fully edentulous patients is costeffective and less expensive. The purpose of the present study was to examine the newly fabricated attachments by comparing them with conventional O-ring attachment in vitro in terms of retention force and cyclic aging resistance. A total of 150 samples were prepared and divided into five groups according to the materials used(O-ring attachment, Deflex M10 XR, Deflex Classic SR, Deflex Acrilato FD, and flexible acrylic resin). The retention force of different attachments was measured by a mini dental implant after three subsequent aging(0, 63, and 126) cycles in the circumstances similar to the oral environment. The gap space between the head of the implant and the inner surface of the attachments was detected. Two-way analysis of variance(ANOVA) analysis with multiple comparisons test was applied for statistical analysis. The results showed that Deflex M10 XR had the highest retention force and the lowest gap space after cyclic aging; in addition, by comparing the relative force reduction, the lowest values were obtained in the O-ring attachment and the highest values in the flexible acrylic resin attachment. The retention force measured after cyclic aging for the Deflex M10 XR attachment was greatly improved when compared with the O-ring attachment and other types of attachment materials; in addition, the Deflex M10 XR attachment exhibited the minimum gap space between the inner surface and the mini dental implant head. In conclusion, Deflex M10 XR has the ability to withstand weathering conditions and retains its durable and retentive properties after aging when compared with other attachments.

关键词： mini dental implant O-ring attachment flexible acrylic resin deflex material

Antimicrobial properties of dental cements modified with zein-coated magnesium oxide nanoparticles

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Bioactive Materials 2022年第2期7卷 49-56页

作者： Ghada H.Naguib Hani M.Nassar Mohamed T.Hamed department of Restorative dentistry Faculty of DentistryKing Abdulaziz UniversityJeddahSaudi Arabia department of Oral Biology Faculty of DentistryCairo UniversityCairoEgypt department of Oral and Maxillofacial prosthodontics King Abdulaziz UniversityFaculty of DentistryJeddahSaudi Arabia department of Fixed prosthodontics Faculty of DentistryCairo UniversityCairoEgypt

The aim of this study was to test the antimicrobial properties of dental cements modified with magnesium oxide(MgO)***-modified MgO nanoparticles(zMgO)in concentrations(0.0,0.3,0.5,and 1.0%)were mixed with dental cements(Fuji II,Rely X Temp E,Ionoglass Cem,Es Temp NE,and System P link).Eight discs were fabricated from each zMgO-cement pair for a total of 32 specimens for each *** of the dental cements incorporating zMgO was done by X-ray Diffraction(XRD)and Field Emission Scanning Electron Microscopy(FESEM).The antimicrobial properties of the mixtures were tested using direct contact and agar diffusion assays against Streptococcus mutans,Staphylococcus aureus,Enterococcus faecalis,and Candida *** was analyzed using two-way analysis of variance and LSD post hoc test at 0.05 significance *** spectra showed sharp peaks of zMgO indicating its high crystalline nature,while the amorphous dental cements with zMgO had broad *** analysis showed a uniform distribution of the zMgO nanoparticles in the *** were significant inhibition zone values associated with all concentrations of zMgO-cement mixtures tested compared to controls(p<0.001)with a dose-response recorded only with Fuji *** density values were significantly lower in zMgO groups compared to controls for all *** effect was most prominent with Rely X against *** and *** cements containing zMgO showed significant antimicrobial properties that were dependent on the specific initial cement substrate.

关键词： Magnesium oxide nanoparticles Antimicrobial biomaterials Dental cement Nanocoatings

Comparison of the clinical efficacy of two different types of post systems which were restored with composite restorations

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World Journal of Clinical Cases 2018年第3期6卷 27-34页

作者： Buket Ayna Emrah Ayna Sema Celenk Emine Goncü Bacaran Berivan Dündar Yιlmaz Ìbrahim Halil Tacir Mehmet Cudi Tuncer department of Pedodontics Faculty of Dentistry Dicle University department of prosthodontics Faculty of Dentistry Dicle University department of Anatomy Faculty of Medicine Dicle University

AIM To compare the efficacy of resin composite restorations, retained with either polyethylene or zirconia-rich glass fiber posts. METHODS Sixty-two single rooted maxillary and mandibularcentral incisor teeth in forty-four patients (15 males and 29 females; age range 15-32 years) were restored either with an ultrahigh molecular weight polyethylene(UHMWP) fiber post (Bondable Reinforcement Ribbon, DENSE, Ribbond, Seattle, WA, United States) or a zircon-rich glass fiber post (Snowpost, Lot H 040; Carbotech, Ganges, France). Then, direct resin composite restoration (Clearfil AP-X, Kuraray) was performed for both post systems in tooth color suitable. Patients were recalled for routine inspections at 6 mo, 1, 2 and 3 *** The restorations were assessed during each recall evaluation according to predetermined clinical and radiographic criteria (periapical lesion; marginal leakage and integrity; color stability; surface stain and loss of retention of the post or the composite buildup material). The follow-up data showed no significant difference in these criteria between polyethylene fibre posts and zirconia-rich glass fibre *** The efficacy of resin composite restorations, retained with either polyethylene or zirconia-rich glass fiber posts were similar, suggesting that both types of fiber post can be used successfully to help retain resin composite restorations.

关键词： Polyethylene fiber Zircon-rich glass fiber Direct composite

Effect of restoration technique on resistance to fracture of endodontically treated anterior teeth with flared root canals

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The Journal of Biomedical Research 2019年第2期33卷 131-138页

作者： Sary S Borzangy Samah M Saker Walid A Al-Zordk department of Substitutive Dental Sciences College of Dentistry Taibah University department of Fixed prosthodontics Faculty of Dentistry Mansoura University

This study was designed to compare the impact of post and core systems on resistance to fracture of endodontically treated anterior teeth with flared root canals and to assess their fracture pattern. Sixty central incisors were cut horizontally 2 mm coronal to the cementoenamel junction(CEJ). After root canal therapy, teeth were assigned into 6 groups(n = 10 each) based on a post system and used as follows: Group C, non-flared root received size #1 glass fiber posts(Control); Group AP, flared root restored with anatomical post; Group RC, flared root restored with size #1 fiber post and cemented with thick layer of resin cement; Group CR, flared root restored with size #1 and reinforced with composite resin; Group CM, cast post-core; Group CP, CAD/CAM polymer-infiltrated ceramic post and *** post cementation, core build-up and crown insertion, the specimens were thermo-cycled up to 10,000 cycles(5 C/55 C; 30 seconds dwell time, 6 seconds transition time) and then statically loaded at 1 mm/minute crosshead speed using a universal testing machine. One-way ANOVA and Tukey HSD post hoc test(α= 0.05) were used for data analysis. Group C recorded significantly higher resistance to fracture values [(826.9±39.1) N] followed by group CP [(793.8±55.6) N] while group RC yielded the lowest fracture resistance values [(586.7±51.4) N]. The resistance to fracture of wide root canals can be enhanced by using one-piece CAM/CAM post and core as an alternative to the use of either glass fiber post, relined with composite resin increasing the thickness of luting cement or the use of cast post and core system. However, this was an in vitro investigation and further in vivo studies are necessary.

关键词： anatomical post customized post endodontically treated teeth flared root canal