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Safari S, Mirzapour A, Sadrmohammadi R. Evaluation of Retention and Fracture Strength of All Ceramic Crowns with Three Different Esthetic Cast Post-Core Systems. Int J Dent 2023; 2023:6664894. [PMID: 37811527 PMCID: PMC10560107 DOI: 10.1155/2023/6664894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/06/2023] [Accepted: 09/10/2023] [Indexed: 10/10/2023] Open
Abstract
Purpose This study investigates the fracture and retention strength of all-ceramic crowns with modified composite resin and ceramic cores compared to conventional casted post and core systems. Materials and Methods A prepared human central tooth was initially scanned to design and 3D print the post and core. Subsequently, 40 bovine teeth were adjusted to accommodate the fabricated post and cores. They were then divided into four groups of 10 each: group 1 comprised cast cores without cover (control group), group 2 involved cast cores reduced and replaced with IPS Empress material (IPS group), group 3 consisted of cast cores covered with opaque composite (composite group), and group 4 included cast cores covered with opaque ceramic (ceramic group). Zirconia crowns were cemented onto all samples. After an aging process, pull-off and fracture strength tests were conducted. Fracture strength was determined by applying a compressive force at an angle of 135° to the tooth's longitudinal axis until the fracture occurred. For retention strength assessment, a universal testing machine with a 10 mm/min crosshead speed was employed. The resulting data underwent statistical analysis utilizing two-way analysis of variance (ANOVA) and Mann-Whitney U tests. Results The analysis revealed no significant difference in fracture strength among the groups (P-value = 0.997). However, the retention strength of the control and IPS groups was significantly higher than that of the other groups. Conclusion There were no discernible distinctions among the three study methods regarding fracture strength. Nonetheless, the retention strength of the IPS group resembled that of the control group, surpassing that of the composite and ceramic groups.
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Affiliation(s)
- Sina Safari
- Student Research Committee and Department of Prosthodontics, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran
| | | | - Roya Sadrmohammadi
- Department of Prosthodontics, School of Dentistry, Kerman University of Medical Sciences, Kerman, Iran
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Heidari N, Amawi R, Seweryniak P, Bakitian F, Vult von Steyern P. Fracture Resistance and Fracture Behaviour of Monolithic Multi-Layered Translucent Zirconia Fixed Dental Prostheses with Different Placing Strategies of Connector: An in vitro Study. Clin Cosmet Investig Dent 2022; 14:61-69. [PMID: 35345450 PMCID: PMC8957397 DOI: 10.2147/ccide.s344941] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 02/03/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose To evaluate the effect of different placing strategies performed in the connector area on fracture resistance and fracture behaviour of monolithic multi-layered translucent zirconia fixed dental prostheses (FDPs). Materials and Methods Thirty 3-unit monolithic FDPs were produced and divided into three groups (n = 10) based on the different strategies for placing the connector area of FDPs in multi-layered zirconia blank with varying contents of yttria ranging from 4 to 5 mol%. The groups were as follows: FDPs with connectors placed in dentin layer with 4 mol% yttria content, FDPs with connectors placed in gradient layer, and FDPs with connectors placed in translucent layer with 5 mol% yttria content. A final group (n = 10) of conventional monolithic zirconia with a monolayer of yttria content (4 mol%) has been used as a control group. The specimens were artificially aged using thermocycling and pre-loading procedures and subsequently loaded to fracture using a universal testing machine. Fracture loads and fracture behaviour were analyzed using one-way ANOVA and Fisher’s exact tests and statistically evaluated (p ≤ 0.05). Results There were no significant differences in fracture loads among the groups based on the placing strategies of the connector area of the FDPs in the multi-layered translucent zirconia blank (p > 0.05). There was no significant difference in fracture loads between monolithic multi-layered translucent zirconia and conventional monolithic translucent zirconia materials (p > 0.05). Fracture behaviour of FDPs with connector area placed in translucent layer differed significantly compared to FDPs with connector area placed in dentin layer and FDPs in control group (p = 0.004). Conclusion The placing strategies of the connector used in the computer aided design and manufacturing procedures do not considerably affect fracture resistance of monolithic FDPs made of multi-layered translucent zirconia. Monolithic FDPs made of multi-layered translucent zirconia show comparable strength to FDPs made of conventional translucent zirconia, but with different fracture behaviour.
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Affiliation(s)
- Nada Heidari
- Department of Materials Science and Technology, Malmö University, Malmö, Sweden
| | - Rasha Amawi
- Department of Materials Science and Technology, Malmö University, Malmö, Sweden
| | | | - Fahad Bakitian
- Department of Restorative Dentistry, Umm Al-Qura University, Makkah, Saudi Arabia
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Vahnström M, Johansson PH, Svanborg P, Stenport VF. Comparison of porcelain veneer fracture in implant-supported fixed full-arch prostheses with a framework of either titanium, cobalt-chromium, or zirconia: An in vitro study. Clin Exp Dent Res 2022; 8:544-551. [PMID: 35313086 PMCID: PMC9033539 DOI: 10.1002/cre2.558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 11/30/2022] Open
Abstract
Objectives The aim of this study was to compare porcelain veneer strength on screw‐retained implant‐supported fixed full‐arch prostheses with a framework of either milled titanium (Ti), cobalt–chromium (CoCr), and yttria‐stabilized zirconia (Y‐TZP) in an in vitro loading model. Materials and Methods Fifteen screw‐retained maxillary implant‐supported full‐arch prostheses (FDP), five each of Ti, CoCr, and Y‐TZP frameworks with porcelain veneers were included. All FDPs were subjected to thermocycling before loading until fracture of the veneer. The load was applied at the distal fossa of the occlusal area of the pontic replacing 24. Fracture loads were analyzed, and the fracture quality was assessed. Statistical analysis on the fracture load was performed using Kruskal–Wallis test. The statistical significance was set at p < .05. Results There was no statistical significance found between the groups regarding fracture load. The highest and lowest load was seen within the CoCr FDP, varying between 340 and 1484 N. Different types of fracture appearances were seen. The Y‐TZP FDPs had a higher number of fractures locally in the loaded area while CoCr and Ti more often showed cracks in the anterior region, at a distance from the loaded area. Conclusions Within the limitations of this study, the conclusion was that framework material may affect the fracture behavior of maxillary full‐arch bridges; however, there were no differences in veneer fracture strength when frameworks of Ti, CoCr, or Y‐TZP were compared.
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Affiliation(s)
- Märta Vahnström
- The Brånemark Clinic, Public Health Service, Region of Västra Götaland, Gothenburg, Sweden
| | - Petra H Johansson
- Department of Prostodontics/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
| | - Per Svanborg
- Department of Prostodontics/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
| | - Victoria F Stenport
- Department of Prostodontics/Dental Materials Science, Institute of Odontology, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
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Lima JMC, Costa AKF, Anami LC, Souza KB, Silva NRD, Marinho RMDM, Borges ALS, Bottino MA, Özcan M, Souza ROA. CAD-FEA modeling and fracture resistance of bilayer zirconia crowns manufactured by the rapid layer technology. Braz Dent J 2021; 32:44-55. [PMID: 34755789 DOI: 10.1590/0103-6440202104163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 03/29/2021] [Indexed: 11/21/2022] Open
Abstract
In the RLT (Rapid Layer Technology), veneering ceramic and framework are fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and then cemented to obtain the restoration. This study aimed to evaluate the effect of the thickness of veneering ceramic manufactured by the RLT technique on the fracture resistance (FR) of bilayer crowns with zirconia frameworks. Twenty zirconia frameworks and twenty feldspathic posterior crowns with two different veneering ceramic occlusal thicknesses (1mm=TF1; 2mm=TF2) were manufactured using CAD/CAM system. The specimens were luted to an epoxy resin abutment with resin cement and mechanically cycled (200N and 4.5×105 Pa, 37°C, 2×106 cycles, 3Hz). The FR test was performed (10kN, 0.5mm/min), and the specimens were analyzed in a stereomicroscope. For the stress analysis (finite element analysis, FEA), a 10kN load was equal to the in vitro test, and the principal stress was evaluated. The FR data were analyzed by Student's t-test and Weibull's analysis. The thickness influenced the FR of bilayer crowns. The FR was higher in the TF2 than in the TF1 group. The TF2 group presented the highest characteristic strength compared to the group TF1. The predominant type of failure was delamination. The FEA showed higher stress concentrations below the loading application point at the veneering cement interface in the 1-mm-thick model. The bilayer crowns manufactured using the approach of 2mm of veneering ceramic promoted higher FR compared to the group with 1mm veneering ceramic. Also, the FEA showed that the veneer ceramic thickness has an effect on stress distribution in zirconia-based bilayer crowns.
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Affiliation(s)
- Julia Magalhães Costa Lima
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Anna Karina Figueiredo Costa
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Lilian Costa Anami
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Karina Barbosa Souza
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Nathalia Ramos da Silva
- Department of Dentistry, Division of Prosthodontics, Federal University of Rio Grande do Norte, Natal, RN, Brazil
| | - Renata Marques de Melo Marinho
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Alexandre Luis Souto Borges
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Marco Antonio Bottino
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology (ICT), São Paulo State University(UNESP/FOSJC), São José dos Campos, SP, Brazil
| | - Mutlu Özcan
- Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, University of Zurich, Zurich, Switzerland
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Alsubaiy EF, Chaturvedi S, Qutub OA, Mously HA, Zarbah MA, Haralur SB, Bhagat TV. Novel CAD-CAM zirconia coping design to enhance the aesthetics and strength for anterior PLZ crowns. Technol Health Care 2021; 29:1161-1171. [PMID: 33998567 DOI: 10.3233/thc-202782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The aesthetics and strength of anterior porcelain layered zirconia (PLZ) crowns are mainly affected by the zirconia (Zr) coping design. There is a need for a modified design to enhance aesthetics with strength. OBJECTIVES The purpose of this study was to compare the fracture resistance of anterior PLZ crowns having modified CAD-CAM Zr coping designs (in terms of thickness and marginal collar designs) with standard Zr copings. METHODS Fifty PLZ crowns were fabricated and divided into two groups: Gr 1: Standard Zr Coping (SZC) (control gr) with 0.5 mm thickness (Facial-F, Mesial-M, Distal-D, incisal-I, and Palatal-P) without a collar; Gr 2: Collar Zr Coping (CZC) (test gr) with 2.5 mm collar height on M, D, P and 0.2 mm F and variable facial wall thickness. Subgroups: Gr 2a: (CZC-0.5 mm) facial wall thickness 0.5 mm; Gr 2b: (CZC-0.4 mm) facial wall thickness 0.4 mm; Gr 2c: (CZC-0.3 mm) facial wall thickness 0.3 mm; Gr 2d: (CZC-0.2 mm) facial wall thickness 0.2 mm. The fracture load was determined and analysed using One-way ANOVA and Dunnet test. RESULTS The minimum fracture load was 927.36 ± 127.80 N observed for Gr 2c (CZC at 0.3 mm) while the maximum fracture load was 1373.61 ± 146.54 N observed for Gr 2a (CZC at 0.5 mm). A highly significant difference in mean fracture load among various Zr coping groups (p< 0.001) was determined. CONCLUSIONS Novel Zr coping design for anterior PLZ crowns can provide better aesthetics with strength. Reducing the thickness of Zr coping in the aesthetic zone to 0.2 mm and providing a modified collar design (2.5 mm collar height on M, D, P, and 0.2 mm F) would provide strength without jeopardizing aesthetics.
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Affiliation(s)
- Ebrahim Fihaid Alsubaiy
- Department of Prosthetic Dentistry, College of Dentistry, King Khalid University, Abha, Saudi Arabia
| | - Saurabh Chaturvedi
- Department of Prosthetic Dentistry, College of Dentistry, King Khalid University, Abha, Saudi Arabia
| | - Osama A Qutub
- Oral and Maxillofacial Prosthodontics Department, College of Dentistry, King Abdulaziz University, Saudi Arabia
| | - Hisham Abdullah Mously
- Oral and Maxillofacial Prosthodontics Department, College of Dentistry, King Abdulaziz University, Saudi Arabia
| | - Mohammad Abdullah Zarbah
- Department of Prosthetic Dentistry, College of Dentistry, King Khalid University, Abha, Saudi Arabia
| | - Satheesh B Haralur
- Department of Prosthetic Dentistry, College of Dentistry, King Khalid University, Abha, Saudi Arabia
| | - Tushar V Bhagat
- College of Dentistry, Prince Sattam bin Abdulaziz University, AlKharj, Saudi Arabia
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Bakitian F, Papia E, Larsson C, Vult von Steyern P. Evaluation of Stress Distribution in Tooth-Supported Fixed Dental Prostheses Made of Translucent Zirconia with Variations in Framework Designs: A Three-Dimensional Finite Element Analysis. J Prosthodont 2020; 29:315-322. [PMID: 31971307 DOI: 10.1111/jopr.13146] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2020] [Indexed: 11/29/2022] Open
Abstract
PURPOSE To evaluate the influence of the framework designs on the stress distribution within tooth-supported partially veneered fixed dental prostheses (FDPs) made of translucent zirconia under simulated loads using a three-dimensional finite element analysis (3D-FEA). MATERIAL AND METHODS For a linear 3D-FEA, simplified 3D solid models of prepared abutment teeth (first premolar and first molar) with different 3-unit FDPs were created. The models with different FDP designs-monolithic zirconia (control); semi-monolithic zirconia with 0.3 mm veneer thickness (SM0.3); semi-monolithic zirconia with 0.5 mm veneer thickness (SM0.5); semi-monolithic zirconia with 0.5 mm veneer thickness supported with cap design (SMC), and semi-monolithic zirconia with 0.5 mm veneer thickness supported with wave design (SMW)-were analyzed using 3D-FEA. The elastic properties of the components (bone, dentine, cement, translucent zirconia, and veneering porcelain) were obtained from the published data for FEA. Simulated static loading forces (300 N) were applied at 10° oblique direction over six points in the occlusal surfaces of the FDPs. Maximum principal stress, shear stress, and safety factor were calculated and analyzed among the different models. RESULTS Semi-monolithic with cap design showed the smallest maximum principal stress levels in the veneering porcelain compared to all other models (SM0.3, SM0.5, SMW). The SM0.3 had lower maximum principal stress levels in the veneering porcelain compared to SM0.5. Regarding stresses in the zirconia framework, all models had comparable results in maximum principal tensile stresses, except SMW had a lower value. Maximum principal stress levels were located in the veneer component of SM0.3, SM0.5, and SMW, whereas, such levels were observed in the cervical areas of the zirconia frameworks of SMC and control. The SM0.3 had the highest maximum shear stress levels at the zirconia-veneer interface, while SMW had the lowest shear values. The 3D-FEA models with different FDP designs showed different minimum safety factor levels. CONCLUSIONS Framework and veneer designs play a significant role in the stress distribution of the partially veneered zirconia FDPs under loading. The FDPs with zirconia frameworks with cap design minimize the maximum principal tensile stress in the veneering porcelain. The FDPs with 0.3-mm-veneering porcelain show low maximum principal tensile stress in the veneering porcelain, but highest maximum shear stress at the zirconia-veneer interface. The FDPs with wave design of zirconia frameworks minimize the maximum shear stress considerably.
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Affiliation(s)
- Fahad Bakitian
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden.,Department of Restorative Dentistry, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Evaggelia Papia
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Christel Larsson
- Department of Prosthodontics, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Per Vult von Steyern
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden
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Bakitian F, Seweryniak P, Papia E, Larsson C, Vult von Steyern P. Effect of different semimonolithic designs on fracture resistance and fracture mode of translucent and high-translucent zirconia crowns. Clin Cosmet Investig Dent 2018; 10:51-60. [PMID: 29628778 PMCID: PMC5878660 DOI: 10.2147/ccide.s157118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose The aim of this study was to describe different designs of semimonolithic crowns made of translucent and high-translucent zirconia materials and to evaluate the effect on fracture resistance and fracture mode. Methods One hundred crowns with different designs were produced and divided into five groups (n=20): monolithic (M), partially veneered monolithic (semimonolithic) with 0.3 mm buccal veneer (SM0.3), semimonolithic with 0.5 mm buccal veneer (SM0.5), semimonolithic with 0.5 mm buccal veneer supported by wave design (SMW), and semimonolithic with 0.5 mm buccal veneer supported by occlusal cap design (SMC). Each group was divided into two subgroups (n=10) according to the materials used, translucent and high-translucent zirconia. All crowns underwent artificial aging before loading until fracture. Fracture mode analysis was performed. Fracture loads and fracture modes were analyzed using two-way ANOVA and Fisher's exact probability tests (P≤0.05). Results SM0.3 design showed highest fracture loads with no significant difference compared to M and SMW designs (P>0.05). SM0.5 design showed lower fracture loads compared to SMW and SWC designs. Crowns made of translucent zirconia showed higher fracture loads compared to those made of high-translucent zirconia. M, SM0.3, and all but one of the SMC crowns showed complete fractures with significant differences in fracture mode compared to SMW and SM0.5 crowns with cohesive veneer fractures (P≤0.05). Conclusion Translucent and high-translucent zirconia crowns might be used in combination with 0.3 mm microcoating porcelain layer with semimonolithic design to enhance the esthetic properties of restorations without significantly decreasing fracture resistance of the crowns. If 0.5 mm porcelain layer is needed for a semimonolithic crown, wave design or cap design might be used to increase fracture resistance. In both cases, fracture resistance gained is likely to be clinically sufficient as the registered fracture loads were high in relation to expected loads under clinical use.
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Affiliation(s)
- Fahad Bakitian
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden.,Department of Restorative Dentistry, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi Arabia
| | | | - Evaggelia Papia
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Christel Larsson
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Per Vult von Steyern
- Department of Materials Science and Technology, Faculty of Odontology, Malmö University, Malmö, Sweden
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Jang YS, Noh HR, Lee MH, Lim MJ, Bae TS. Effect of Lithium Disilicate Reinforced Liner Treatment on Bond and Fracture Strengths of Bilayered Zirconia All-Ceramic Crown. MATERIALS 2018; 11:ma11010077. [PMID: 29303973 PMCID: PMC5793575 DOI: 10.3390/ma11010077] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 12/22/2017] [Accepted: 01/03/2018] [Indexed: 11/23/2022]
Abstract
This study was performed to evaluate the effect of a lithium-disilicate spray-liner application on both the bond strength between zirconia cores and heat-pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of all-ceramic zirconia crowns. A lithium-disilicate reinforced liner was applied on the surface of a zirconia core and lithium-disilicate glass-ceramic was veneered on zirconia through heat press forming. Microtensile and crown fracture tests were conducted in order to evaluate, respectively, the bonding strength between the zirconia cores and heat pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of bilayered zirconia all-ceramic crowns. The role of lithium-disilicate spray-liner at the interface between zirconia and lithium-disilicate glass-ceramic veneers was investigated through surface and cross-sectional analyses. We confirmed that both the mean bonding strength between the zirconia ceramics and lithium-disilicate glass-ceramic veneers and the fracture strength of the liner-treated groups were significantly higher than those of the untreated groups, which resulted, on the one hand, from the chemical bonding at the interface of the zirconia and lithium-disilicate liner, and, on the other, from the existence of a microgap in the group not treated with liner.
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Affiliation(s)
- Yong-Seok Jang
- Department of Dental Biomaterials, Institute of Biodegradable Materials, BK21 Plus Program, School of Dentistry, Chonbuk National University, Jeonju 54896, Korea.
| | - Hyeong-Rok Noh
- Department of Dental Biomaterials, Institute of Biodegradable Materials, BK21 Plus Program, School of Dentistry, Chonbuk National University, Jeonju 54896, Korea.
| | - Min-Ho Lee
- Department of Dental Biomaterials, Institute of Biodegradable Materials, BK21 Plus Program, School of Dentistry, Chonbuk National University, Jeonju 54896, Korea.
| | - Myung-Jin Lim
- Department of Conservative Dentistry, School of Dentistry, Chonbuk National University, Jeonju 54896, Korea.
| | - Tae-Sung Bae
- Department of Dental Biomaterials, Institute of Biodegradable Materials, BK21 Plus Program, School of Dentistry, Chonbuk National University, Jeonju 54896, Korea.
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