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de Oliveira Limirio JPJ, Gomes JMDL, Santiago-Junior JF, Nagay BE, Pesqueira AA, Assunção WG, Alves-Rezende MCR, Pellizzer EP. Influence of ceramic crown design (translucent monolithic zirconia vs. bilayered) of implant-supported single crowns after mechanical cycling. J ESTHET RESTOR DENT 2024; 36:1326-1336. [PMID: 38665052 DOI: 10.1111/jerd.13237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 03/20/2024] [Accepted: 04/03/2024] [Indexed: 08/11/2024]
Abstract
OBJECTIVES This study aimed to assess the influence of translucent monolithic versus bilayered crowns and whether the use of a CoCr base abutments affects the fatigue and fracture resistance of screwed implant-supported single crowns with external connections under mechanical cycling. MATERIALS AND METHODS Fifty specimens were divided into groups: (1) metal-ceramic (MC) crown, (2) veneered zirconia crown (Zr), (3) veneered zirconia crown with a CoCr base abutment (ZrB), (4) monolithic translucent zirconia crown (MZr), and (5) monolithic translucent zirconia crown with a CoCr base abutment (MZrB). Specimens underwent mechanical cycling (5 × 106 cycles; 150 N) evaluating fatigue resistance (number of failures) and those that failed were subsequently subjected to fractographic analyses (stereomicroscope and scanning electron microscope) to evaluate failure location and area, and maximum fracture load was also measured. RESULTS The failure-related survival rate (100%) and maximum fracture resistance of the MZrB were significantly higher than those of MC and Zr (50%; p < 0.05). There were no significant differences in the failure rate and fracture resistance when a CoCr base abutment was used or not in the translucent monolithic Zr groups (p > 0.05;MZrB vs. MZr). Failure location, with MC crowns' fractures, noted at the screw area (p = 0.043), while all-ceramic crowns were mostly in the cuspid and to failure area, the Zr group had the largest mean (15.55 ± 9.17 mm2) among the groups, significant difference only when compared with MC (1.62 ± 0.81 mm2) (p = 0.025). CONCLUSIONS Translucent monolithic zirconia crowns exhibited significantly higher fatigue and fracture resistance compared with conventional MC and bilayered crowns. CLINICAL SIGNIFICANCE The appropriate choice of material and manufacturing technique is crucial for predicting the higher clinical performance of single crowns. Enhanced mechanical resistance in terms of fatigue and fracture resistance can be achieved by replacing MC and bilayered restorations with computer-aided design and computer-aided manufacturing monolithic zirconia.
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Affiliation(s)
| | - Jéssica Marcela de Luna Gomes
- Department of Dental Materials and Prosthodontics, Sao Paulo State University (UNESP), School of Dentistry, Araçatuba, São Paulo, Brazil
| | | | - Bruna Egumi Nagay
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil
| | - Aldiéris Alves Pesqueira
- Department of Dental Materials and Prosthodontics, Sao Paulo State University (UNESP), School of Dentistry, Araçatuba, São Paulo, Brazil
| | - Wirley Gonçalves Assunção
- Department of Dental Materials and Prosthodontics, Sao Paulo State University (UNESP), School of Dentistry, Araçatuba, São Paulo, Brazil
| | | | - Eduardo Piza Pellizzer
- Department of Dental Materials and Prosthodontics, Sao Paulo State University (UNESP), School of Dentistry, Araçatuba, São Paulo, Brazil
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Refaie A, Bourauel C, Elshazly T, Evers-Dietze B, Alhotan A, Aldesoki M. Trueness and precision of digital light processing fabricated 3D printed monolithic zirconia crowns. J Dent 2024; 148:105151. [PMID: 38909644 DOI: 10.1016/j.jdent.2024.105151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 06/18/2024] [Accepted: 06/21/2024] [Indexed: 06/25/2024] Open
Abstract
OBJECTIVES The present study aimed to evaluate the trueness and precision of monolithic zirconia crowns (MZCs) fabricated by 3D printing and milling techniques. METHODS A premolar crown was designed after scanning a prepared typodont. Twenty MZCs were fabricated using milling and 3D-printing techniques (n = 10). All the specimens were scanned with an industrial scanner, and the scanned data were analyzed using 3D measurement software to evaluate the trueness and precision of each group. Root mean square (RMS) deviations were measured and statistically analyzed (One-way ANOVA, Tukey's, p ≤ 0.05). RESULTS The trueness of the printed MZC group (140 ± 14 μm) showed a significantly higher RMS value compared to the milled MZCs (96 ± 27 μm,p < 0.001). At the same time, the precision of the milled MZCs (61 ± 17 μm) showed a significantly higher RMS value compared to that of the printed MZCs (31 ± 5 μm,p < 0.001). CONCLUSIONS The Fabrication techniques had a significant impact on the accuracy of the MZCs. Milled MZCs showed the highest trueness, while printed MZCs showed the highest precision. All the results were within the clinically acceptable error values. CLINICAL SIGNIFICANCE Although the trueness of the milled MZCs is higher, the manufacturing accuracy of the 3D-printed MZCs showed clinically acceptable results in terms of trueness and precision. However, additional clinical studies are recommended. Furthermore, the volumetric changes of the material should be considered.
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Affiliation(s)
- Ashraf Refaie
- Oral Technology, Dental School, University Hospital Bonn, Bonn, Germany; Department of Fixed Prosthodontics, Faculty of Dentistry, Fayoum University, Egypt.
| | | | - Tarek Elshazly
- Oral Technology, Dental School, University Hospital Bonn, Bonn, Germany
| | - Bernd Evers-Dietze
- Department of Electrical Engineering, Mechanical Engineering and Technical Journalism (EMT), Bonn-Rhein-Sieg University of Applied Sciences, Sankt Augustin, Germany
| | - Abdulaziz Alhotan
- Department of Dental Health, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Mostafa Aldesoki
- Oral Technology, Dental School, University Hospital Bonn, Bonn, Germany
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Strasding M, Marchand L, Merino E, Zarauz C, Pitta J. Material and abutment selection for CAD/CAM implant-supported fixed dental prostheses in partially edentulous patients - A narrative review. Clin Oral Implants Res 2024; 35:984-999. [PMID: 38864592 DOI: 10.1111/clr.14315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 05/15/2024] [Accepted: 05/27/2024] [Indexed: 06/13/2024]
Abstract
Restorative material selection has become increasingly challenging due to the speed of new developments in the field of dental material science. The present narrative review gives an overview of the current indications for implant abutments and restoration materials for provisional and definitive implant-supported fixed dental prostheses in partially edentulous patients. For single implant restorations, titanium base abutments for crowns are suggested as an alternative to the conventional stock- and customized abutments made out of metal or zirconia. They combine the mechanical stability of a metallic connection with the esthetic potential of ceramics. For multiple-unit restorations, conical titanium bases especially designed for bridges are recommended, to compensate for deviating implant insertion axes and angulations. Even though titanium base abutments with different geometries and heights are available, certain clinical scenarios still benefit from customized titanium abutments. Indications for the definitive material in fixed implant restorations depend on the region of tooth replacement. In the posterior (not esthetically critical) zone, ceramics such as zirconia (3-5-Ymol%) and lithium-disilicate are recommended to be used in a monolithic fashion. In the anterior sector, ceramic restorations may be buccally micro-veneered for an optimal esthetic appearance. Lithium-disilicate is only recommended for single-crowns, while zirconia (3-5-Ymol%) is also recommended for multiple-unit and cantilever restorations. Attention must be given to the specific mechanical properties of different types of zirconia, as some feature reduced mechanical strengths and are therefore not indicated for all regions and restoration span lengths. Metal-ceramics remain an option, especially for cantilever restorations.
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Affiliation(s)
- Malin Strasding
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Laurent Marchand
- Department of Prosthodontics, School of Dental Medicine, Tufts University, Boston, Massachusetts, USA
| | - Elizabeth Merino
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Cristina Zarauz
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - João Pitta
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
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Huang B, Chen M, Wang J, Zhang X. Advances in zirconia-based dental materials: Properties, classification, applications, and future prospects. J Dent 2024; 147:105111. [PMID: 38866229 DOI: 10.1016/j.jdent.2024.105111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 06/04/2024] [Accepted: 06/06/2024] [Indexed: 06/14/2024] Open
Abstract
OBJECTIVES Zirconia (ZrO2) ceramics are widely used in dental restorations due to their superior mechanical properties, durability, and ever-improving translucency. This review aims to explore the properties, classification, applications, and recent advancements of zirconia-based dental materials, highlighting their potential to revolutionize dental restoration techniques. STUDY SELECTION, DATA AND SOURCES The most recent literature available in scientific databases (PubMed and Web of Science) reporting advances of zirconia-based materials within the dental field is thoroughly examined and summarized, covering the major keywords "dental zirconia, classification, aesthetic, LTD, applications, manufacturing, surface treatments". CONCLUSIONS An exhaustive overview of the properties, classifications, and applications of dental zirconia was presented, alongside an exploration of future prospects and potential advances. This review highlighted the importance of addressing challenges such as low-temperature degradation resistance and optimizing the balance between mechanical strength and translucency. Also, innovative approaches to improve the performances of zirconia as dental material was discussed. CLINICAL SIGNIFICANCE This review provides a better understanding of zirconia-based dental biomaterials for dentists, helping them to make better choice when choosing a specific material to fabricate the restorations or to place the implant. Moreover, new generations of zirconia are still expected to make progress on key issues such as the long-term applications in dental materials while maintaining both damage resistance and aesthetic appeal, defining the directions for future research.
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Affiliation(s)
- Bo Huang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Mengbing Chen
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China
| | - Jian Wang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China.
| | - Xin Zhang
- State Key Laboratory of Oral Diseases & National Center for Stomatology & National Clinical Research Center for Oral Diseases & Department of Prosthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, Sichuan, China.
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Işisağ Ö, Pektaş N. Comparison of the fracture strengths of single-unit metal-ceramic and monolithic zirconium restorations in the molar region: a systematic review and meta-analysis. Odontology 2024; 112:751-760. [PMID: 38103151 DOI: 10.1007/s10266-023-00878-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 11/17/2023] [Indexed: 12/17/2023]
Abstract
Despite the success of monolithic zirconia restorations (MZ), metal-ceramic restorations (MC) are still considered the gold standard for fixed prosthetics in the posterior region. This systematic review and meta-analysis aimed to compare the fracture strengths of single-unit MC and MZ in the molar region. This review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA, 2020) statement. All articles were searched from the PubMed and Web of Science databases until November 18, 2022. All in vitro studies evaluating the fracture strengths of MC and MZ were also included. Statistical analysis was performed with the Comprehensive Meta-Analysis program, with a significance level of 0.05. Out of 753 studies, five were selected. The fracture strengths of MZ and MC did not show any statistically significant difference for both tooth (95% CI - 1.589: 2.118, p = 0.779, z = 0.280) and implant (95% CI - 2.215: 2.191, p = 0.992 z = - 0.010) supported restorations. However, different abutment materials (p < 0.001) and aging treatments (p < 0.001) in tooth-supported restorations displayed a significant statistical difference. Additionally, a significant difference was also observed in subgroup analysis considering different cements (p = 0.001) and load speeds (p = 0.001) in implant-supported restorations. Fracture strengths of MZ and MC did not show a significant statistical difference in implant or tooth-supported single-unit posterior restorations. MZ may be a suitable alternative to MC in single-unit posterior restorations. The results should be interpreted with caution, as the included studies were in vitro.
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Affiliation(s)
- Özer Işisağ
- Department of Prosthodontics, Faculty of Dentistry, Afyonkarahisar Health Sciences University, Inonu Boulevard No: 4, Afyonkarahisar, Turkey.
| | - Nur Pektaş
- Department of Prosthodontics, Faculty of Dentistry, Afyonkarahisar Health Sciences University, Inonu Boulevard No: 4, Afyonkarahisar, Turkey
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Rodrigues JVM, Demachkia AM, da Silva de Assis RAS, Gomes MM, Campos TMB, Dapieve KS, Valandro LF, de Melo RM. Fatigue and failure mode analyses of glass infiltrated 5Y-PSZ bonded onto dentin analogues. Sci Rep 2024; 14:13262. [PMID: 38858417 PMCID: PMC11164944 DOI: 10.1038/s41598-024-64110-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 06/05/2024] [Indexed: 06/12/2024] Open
Abstract
The purpose of this study was to evaluate the fatigue survival of 5Y-PSZ zirconia infiltrated with an experimental glass and bonded onto dentin analogues. Disc-shaped specimens of a 5Y-PSZ (Katana UTML Kuraray Noritake) were cemented onto dentin analogs (NEMA G10) and divided into four groups (n = 15): Zctrl Group (control, without infiltration); Zglz Group (Glaze, compression surface); Zinf-comp Group (Experimental Glass, compression surface); Zinf-tens Group (Experimental Glass, tension surface). Surface treatments were varied. Cyclic fatigue loading, oblique transillumination, stereomicroscope examination, and scanning electron microscopy were performed. Fatigue data were analyzed (failure load and number of cycles) using survival analysis (Kaplan-Meier and Log-Rank Mantel-Cox). There was no statistically significant difference in fatigue survival between the Zglz, Zctrl, and Zinf-comp groups. The Zinf-tens group presented a significantly higher failure load when compared to the other groups and exhibited a different failure mode. The experimental glass effectively infiltrated the zirconia, enhancing structural reliability, altering the failure mode, and improving load-bearing capacity over more cycles, particularly in the group where the glass was infiltrated into the tensile surface of the zirconia. Glass infiltration into 5Y-PSZ zirconia significantly enhanced structural reliability and the ability to withstand loads over an increased number of cycles. This approach has the potential to increase the durability of zirconia restorations, reducing the need for replacements and save time and resources, promoting efficiency in clinical practice.
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Affiliation(s)
- Jonas Vinicius Meireles Rodrigues
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), Av. Engenheiro Francisco José Longo, 777, Jardim São Dimas, São José dos Campos, São Paulo, 12245-000, Brazil
| | - Amir Mohidin Demachkia
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), Av. Engenheiro Francisco José Longo, 777, Jardim São Dimas, São José dos Campos, São Paulo, 12245-000, Brazil
| | - Rita Adriana Souza da Silva de Assis
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), Av. Engenheiro Francisco José Longo, 777, Jardim São Dimas, São José dos Campos, São Paulo, 12245-000, Brazil.
| | - Mariana Marques Gomes
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), Av. Engenheiro Francisco José Longo, 777, Jardim São Dimas, São José dos Campos, São Paulo, 12245-000, Brazil
| | - Tiago Moreira Bastos Campos
- Aeronautics Technological Institute (ITA), Praça Marechal Eduardo Gomes, 50, Vila das Acácias, São José dos Campos, São Paulo, 12228-900, Brazil
| | - Kiara Serafini Dapieve
- Post-Graduate Program in Oral Science, Faculty of Dentistry, Federal University of Santa Maria (UFSM), Av. Roraima, 1000, Cidade Universitária, Camobi, Santa Maria, Rio Grande do Sul, 97105-900, Brazil
| | - Luiz Felipe Valandro
- Post-Graduate Program in Oral Science, Faculty of Dentistry, Federal University of Santa Maria (UFSM), Av. Roraima, 1000, Cidade Universitária, Camobi, Santa Maria, Rio Grande do Sul, 97105-900, Brazil
| | - Renata Marques de Melo
- Department of Dental Materials and Prosthodontics, Institute of Science and Technology, São Paulo State University (UNESP), Av. Engenheiro Francisco José Longo, 777, Jardim São Dimas, São José dos Campos, São Paulo, 12245-000, Brazil
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Kobayashi T, Honda J, Kubochi K, Iwasaki T, Watanabe Y, Komine F. Influence of attaching mechanical retentive devices onto frameworks on fracture resistance of implant-supported zirconia crowns. Dent Mater J 2024; 43:359-366. [PMID: 38583996 DOI: 10.4012/dmj.2023-188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
This study investigated the fracture load of implant-supported zirconia crowns (IZCs), in which indirect composite resin or feldspathic porcelain was layered onto zirconia frameworks with mechanical retentive devices. Three different zirconia frameworks were assessed: attaching mechanical retentive devices on glaze and opaque porcelain materials (GL and OP groups, respectively), and no attaching mechanical retentive devices (ND group). The frameworks were layered using feldspathic porcelain (FP veneer) and indirect composite resin (IC veneer). Fracture load of the specimens was measured. In FP veneer, the GL group recorded the highest fracture load. In the IC veneer, the GL and OP groups had significantly higher fracture load than the ND group. The fracture resistance of IZCs can be enhanced by applying glaze material before attaching mechanical retentive devices for porcelain layering. The mechanical retentive devices effectively yielded mechanical interlocking between the zirconia frameworks and the IC veneer in GL and OP groups.
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Affiliation(s)
- Tatsuro Kobayashi
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Junichi Honda
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Kei Kubochi
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Taro Iwasaki
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Yusuke Watanabe
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Futoshi Komine
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
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Rues S, Herpel C, Ilani A, Schmitt C, Rammelsberg P, Schwindling FS. Effect of firing time and wall thickness on the biaxial flexural strength of 3D-printed zirconia. Dent Mater 2024; 40:484-492. [PMID: 38155019 DOI: 10.1016/j.dental.2023.12.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 12/13/2023] [Accepted: 12/19/2023] [Indexed: 12/30/2023]
Abstract
OBJECTIVES To evaluate the effect of accelerated firing on 3D-printed zirconia. METHODS To check if formulae provided by ISO 6872 can be extended to thin samples, finite element analyses were carried out in advance of fabricating 3-mol% yttria-stabilized tetragonal zirconia polycrystal discs by milling and by 3D-printing. Four groups (n = 38 each) of 3D-printed specimens were produced with two nominal thicknesses (0.6 mm and 1.2 mm) and two firing strategies (long: 51 h, accelerated: 14.5 h). In the milled group (thickness 1.2 mm, n = 30), a standard firing program (9.8 h) was selected. Biaxial flexural strength tests were applied and mean strength, characteristic strength, and Weibull modulus were calculated for each group. Differences were analyzed using Welch ANOVA and Dunnett-T3 post-hoc tests. RESULTS Maximum tensile stresses occurring during biaxial strength testing can be calculated according to ISO 6872 for thin samples with b > 0.3 mm. Variability of measured strengths values was smaller for milled zirconia compared with 3D-printed zirconia. The 1.2-mm-thick 3D-printed samples had significantly decreased strength after accelerated firing than after long firing. However, for the 0.6-mm-thick samples, comparable mean biaxial strength values of about 1000 MPa were measured for both firing protocols. SIGNIFICANCE At the moment, long fabrication time for zirconia restorations is a major drawback of 3D-printing when compared with milling technology. This investigation showed that the strength of 0.6-mm-thick zirconia discs fabricated by 3D-printing was not impaired by accelerated firing. Thus, overnight firing of thin-walled 3D-printed zirconia restorations could be possible.
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Affiliation(s)
- Stefan Rues
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany.
| | - Christopher Herpel
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Ali Ilani
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Clemens Schmitt
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany; Department of Prosthetic Dentistry, Medical University Innsbruck, Innsbruck, Austria
| | - Peter Rammelsberg
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Franz Sebastian Schwindling
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany; Department of Prosthetic Dentistry, Medical University Innsbruck, Innsbruck, Austria
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Wang L, Wang K, Sheng Y, Hao Z, Tang W, Dou R. The effect of phase contents on the properties of yttria stabilized zirconia dental materials fabricated by stereolithography-based additive manufacturing. J Mech Behav Biomed Mater 2024; 150:106313. [PMID: 38109815 DOI: 10.1016/j.jmbbm.2023.106313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/05/2023] [Accepted: 12/07/2023] [Indexed: 12/20/2023]
Abstract
The aim is to investigate the impact of phase contents on mechanical properties, translucency, and aging stability of additively manufactured yttria partially stabilized zirconia ceramics. For that purpose, we evaluated two PSZ materials. The first type was prepared utilizing commercially available 5 mol% yttria-stabilized zirconia(5Y-PSZ), while the second type, denoted as 3Y+8Y-PSZ ceramics, was fabricated by blending 3 mol% and 8 mol% yttria-stabilized zirconia powders. Compared to 5Y-PSZ (39.90 wt% tetragonal phases and c/a2 = 1.0141), 3Y+8Y-PSZ is characterized by a greater abundance of tetragonal phases (47.68 wt%), which display higher tetragonality (c/a2 = 1.0165) and lower yttrium oxide content (2.25mol%). As a result, the 3Y+8Y-PSZ demonstrates elevated strength (816.52 MPa) and toughness (4.32 MPa m1/2), accompanied by reduced translucency(CR:0.47) and it exhibits greater susceptibility to aging. The phase contents, yttrium oxide content, and lattice parameters in the tetragonal phase play a crucial role in determining the mechanical properties, translucency, and aging stability of PSZ ceramics.
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Affiliation(s)
- Li Wang
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, Jiangsu, China; Institute of Advanced Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
| | - Kang Wang
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, Jiangsu, China; Institute of Advanced Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Yang Sheng
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, Jiangsu, China; Institute of Advanced Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Zongdong Hao
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, Jiangsu, China; Institute of Advanced Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Weizhe Tang
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, Jiangsu, China; Institute of Advanced Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Rui Dou
- Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, School of Mechanical Engineering, Jiangnan University, Wuxi, 214122, Jiangsu, China; Institute of Advanced Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
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Campos TMB, Dos Santos C, Alves LMM, Benalcazar-Jalkh EB, Strazzi-Sahyon HB, Bergamo ETP, Tebcherani SM, Witek L, Coelho PG, Yamaguchi S, Thim GP, Bonfante EA. Minimally processed recycled yttria-stabilized tetragonal zirconia for dental applications: Effect of sintering temperature on glass infiltration. J Mech Behav Biomed Mater 2024; 150:106311. [PMID: 38128470 DOI: 10.1016/j.jmbbm.2023.106311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Revised: 12/03/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
This study aimed to develop a recycling process for the remnants of milled 3Y-TZP and enhance their properties using glass infiltration. 3Y-TZP powder was gathered from the vacuum system of CAD-CAM milling equipment, calcined and sieved (x < 75 μm). One hundred twenty discs were fabricated and pre-sintered at 1000 °C/h. These specimens were then divided into four groups, categorized by glass infiltration (non-infiltrated [Zr] or glass-infiltrated [Zr-G]) and sintering temperature (1450 °C [Zr-1450] or 1550 °C [Zr-1550]/2h). After sintering, the specimens were characterized by X-Ray Diffraction (XRD), relative density measurement, and scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). The biaxial flexural strength test was performed according to the ISO 6872 and followed by fractographic analysis. Subsequent results were analyzed using Weibull statistics. Relative density values of the sintered specimens from Zr-1450 and Zr-1550 groups were 86.7 ± 1.5% and 92.2 ± 1.7%, respectively. Particle size distribution revealed particles within the range of 0.1-100 μm. XRD analysis highlighted the presence of the ZrO2-tetragonal in both the Zr-1450 and Zr-1550 groups. Glass infiltration, however, led to the formation of the ZrO2-monoclinic of 9.84% (Zr-1450-G) and 18.34% (Zr-1550-G). SEM micrographs demonstrated similar microstructural characteristics for Zr-1450 and Zr-1550, whereas the glass-infiltrated groups exhibited comparable infiltration patterns. The highest characteristic strength was observed in the glass-infiltrated groups. Fractographic analyses suggested that fracture origins were related to defects on the tensile side, which propagated to the compression side of the samples. Both the sintering temperature and glass infiltration significantly influenced the mechanical properties of the 3Y-TZP recycled.
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Affiliation(s)
- Tiago Moreira Bastos Campos
- Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Bauru, SP, Brazil
| | - Claudinei Dos Santos
- Faculty of Technology, University of Rio de Janeiro State (UERJ - FAT), Resende, RJ, Brazil
| | - Larissa Marcia Martins Alves
- Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Bauru, SP, Brazil.
| | - Ernesto B Benalcazar-Jalkh
- Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Bauru, SP, Brazil
| | | | - Edmara T P Bergamo
- Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Bauru, SP, Brazil; Biomaterials Division, New York University College of Dentistry, New York, NY, USA
| | - Sérgio Mazurek Tebcherani
- Department of Production Engineering, Federal University of Technology, Paraná, Ponta Grossa, PR, Brazil
| | - Lukasz Witek
- Biomaterials Division, New York University College of Dentistry, New York, NY, USA; Department of Biomedical Engineering, NYU Tandon School of Engineering, New York University, Brooklyn, NY, USA
| | - Paulo G Coelho
- Division of Plastic Surgery, Department of Surgery, University of Miami Miller School of Medicine, Miami, FL, USA; Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Satoshi Yamaguchi
- Department of Dental Biomaterials, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan
| | - Gilmar P Thim
- Department of Physics, Aeronautics Technological Institute, São José Dos Campos, SP, Brazil
| | - Estevam A Bonfante
- Department of Prosthodontics and Periodontology, University of São Paulo - Bauru School of Dentistry, Bauru, SP, Brazil
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11
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Zhang M, Ho DKL, Pelekos G, Fok MR. Clinical performance of implant-supported single hybrid abutment crown restoration: A systematic review and meta-analysis. J Prosthodont Res 2024; 68:63-77. [PMID: 37316260 DOI: 10.2186/jpr.jpr_d_22_00279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
PURPOSE To investigate survival rates and technical and biological complications of one-piece screw-retained hybrid abutments in implant-supported single crowns (SCs). STUDY SELECTION An electronic search was performed on five databases for clinical studies involving implant-supported single hybrid abutment crowns constructed using titanium-base (Ti base) abutments, with at least 12 months of follow-up. The RoB 2, Robins-I, and JBI tools were used to assess the risk of bias for the different study types. Success, survival, and complication rates were calculated, and a meta-analysis was performed to obtain a pooled estimate. Peri-implant health parameters were extracted and analyzed. RESULTS 22 records (20 studies) were included in this analysis. Direct comparisons between screw-retained hybrid abutment SCs and cemented SCs showed no significant differences in the 1-year survival and success rates. For SCs using a hybrid abutment crown design, their 1-year survival rate was 100% (95% CI: 100%-100%, I2 = 0.0%, P = 0.984), and a success rate of 99% (95% CI: 97%-100%, I2 = 50.3%, P = 0.023) was calculated. No confounding variables significantly affected the estimates. The individual technical complication rate was low at 1-year follow-up. The estimated incidence of all types of complications in hybrid abutment SCs is less than 1%. CONCLUSIONS Within the limitations of this study, implant-supported SCs using a hybrid abutment crown design showed favorable short-term clinical outcomes. Additional well-designed clinical trials with at least a 5-year observation period are required to confirm their long-term clinical performance.
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Affiliation(s)
- Mengze Zhang
- Division of Periodontology and Implant Dentistry, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Dominic King Lun Ho
- Division of Periodontology and Implant Dentistry, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - George Pelekos
- Division of Periodontology and Implant Dentistry, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
| | - Melissa Rachel Fok
- Division of Periodontology and Implant Dentistry, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, China
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12
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Nokar K, Atri F, Nokar S. Comparative Evaluation of the Effect of Implant Crown Materials on Implant Components and Bone Stress Distribution: A 3D Finite Element Analysis. Int J Dent 2023; 2023:1896475. [PMID: 38130700 PMCID: PMC10735729 DOI: 10.1155/2023/1896475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 11/06/2023] [Accepted: 11/23/2023] [Indexed: 12/23/2023] Open
Abstract
Background Choosing implant crown materials for restoration remains challenging in clinical practice. This study assesses the impact of all-ceramic restoration instead of porcelain-fused-to-metal (PFM) restoration on the stress distribution within implant components and the surrounding bone. Methods Four 3D models of a mandibular second premolar were meticulously prepared. The study groups comprised zirconia, lithium disilicate, and zirconia lithium silicate monolithic ceramic crowns cemented onto a zirconia hybrid abutment. A PFM crown cemented onto a cementable abutment was chosen as the control group. A total vertical load of 583 N was applied to the occlusal contact areas. Stress distribution within the crown and implant components was analyzed using von Mises stress analysis. Principal stress analyses were employed to assess stress distribution in the peripheral bone. Results The PFM model exhibited the highest von Mises stress values for both the implant (428.7 MPa) and crown (79.7 MPa) compared to the other models. The all-ceramic models displayed the highest maximum von Mises stress within the abutment, approximately 335 MPa, compared to the PFM model. von Mises stresses of the abutment and implant in the all-ceramic models were 69% higher and 20% lower, respectively, than those in the PFM model. Screw stresses were relatively consistent across all groups. Principal stresses in spongy bone and minimum principal stress in cortical bone were consistent across all models. Conclusions All-ceramic restoration with a hybrid abutment, as opposed to traditional PFM restoration with a cementable abutment, does not adversely affect the implant and abutment screw and reduces crown stresses. Stresses within hybrid abutments were notably higher than those within cementable abutments. Spongy bone stresses remained unaffected by the type of crown or abutment.
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Affiliation(s)
- Kimia Nokar
- School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Faezeh Atri
- Department of Prosthodontics, School of Dentistry, Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Saied Nokar
- Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
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13
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Benalcázar-Jalkh EB, Bergamo ETP, Campos TMB, Coelho PG, Sailer I, Yamaguchi S, Alves LMM, Witek L, Tebcherani SM, Bonfante EA. A Narrative Review on Polycrystalline Ceramics for Dental Applications and Proposed Update of a Classification System. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7541. [PMID: 38138684 PMCID: PMC10744432 DOI: 10.3390/ma16247541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/07/2023] [Accepted: 11/25/2023] [Indexed: 12/24/2023]
Abstract
Dental zirconias have been broadly utilized in dentistry due to their high mechanical properties and biocompatibility. Although initially introduced in dentistry as an infrastructure material, the high rate of technical complications related to veneered porcelain has led to significant efforts to improve the optical properties of dental zirconias, allowing for its monolithic indication. Modifications in the composition, processing methods/parameters, and the increase in the yttrium content and cubic phase have been presented as viable options to improve zirconias' translucency. However, concerns regarding the hydrothermal stability of partially stabilized zirconia and the trade-off observed between optical and mechanical properties resulting from the increased cubic content remain issues of concern. While the significant developments in polycrystalline ceramics have led to a wide diversity of zirconia materials with different compositions, properties, and clinical indications, the implementation of strong, esthetic, and sufficiently stable materials for long-span fixed dental prostheses has not been completely achieved. Alternatives, including advanced polycrystalline composites, functionally graded structures, and nanosized zirconia, have been proposed as promising pathways to obtain high-strength, hydrothermally stable biomaterials. Considering the evolution of zirconia ceramics in dentistry, this manuscript aims to present a critical perspective as well as an update to previous classifications of dental restorative ceramics, focusing on polycrystalline ceramics, their properties, indications, and performance.
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Affiliation(s)
- Ernesto B. Benalcázar-Jalkh
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
| | - Edmara T. P. Bergamo
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
- Biomaterials Division, NYU Dentistry, New York, NY 10010, USA
- Department of Prosthodontics, NYU Dentistry, New York, NY 10010, USA
| | - Tiago M. B. Campos
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
| | - Paulo G. Coelho
- DeWitt Daughtry Family Department of Surgery, Division of Plastic Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Irena Sailer
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Satoshi Yamaguchi
- Department of Dental Biomaterials, Osaka University Graduate School of Dentistry, Suita 565-0871, Osaka, Japan;
| | - Larissa M. M. Alves
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
| | - Lukasz Witek
- Biomaterials Division, NYU Dentistry, New York, NY 10010, USA
- Department of Biomedical Engineering, NYU Tandon School of Engineering, New York University, Brooklyn, NY 11201, USA
- Hansjörg Wyss Department of Plastic Surgery, NYU Grossman School of Medicine, New York, NY 10017, USA
| | - Sérgio M. Tebcherani
- Department of Production Engineering, Federal University of Technology—Paraná, Av. Monteiro Lobato Km 04, Ponta Grossa 84016-210, PR, Brazil;
| | - Estevam A. Bonfante
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
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14
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Zumstein K, Waller T, Hämmerle CHF, Jung RE, Benic G, Mühlemann S. Clinical performance of monolithic zirconia crowns on titanium-zirconium reduced-diameter implants in the molar area: Interim data at three years of a randomized controlled trial. Clin Oral Implants Res 2023; 34:1354-1362. [PMID: 37668109 DOI: 10.1111/clr.14179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 08/10/2023] [Accepted: 08/23/2023] [Indexed: 09/06/2023]
Abstract
AIM The aim of the present study was (i) to evaluate the clinical performance of reduced-diameter implants placed in the molar area and (ii) to test whether monolithic zirconia implant-supported crowns lead to similar clinical outcomes compared to porcelain-fused-to-metal crowns. MATERIALS AND METHODS A total of 76 patients needing a single implant crown in the posterior region were recruited. All patients received a titanium-zirconium reduced-diameter implant (Straumann Roxolid, Tissue Level, Standard Plus, diameter 3.3 mm, regular neck) randomly allocated to receive either a (1) monolithic zirconia crown (test) or (2) porcelain-fused-to-metal crown (control). Implant survival, prosthetic outcomes, and patient-reported outcomes were assessed at crown delivery and after 3 years of follow-up. Marginal bone levels (MBL) as well as clinical parameters including probing depth (PD), bleeding on probing (BOP), and plaque levels (PCR) were also recorded. RESULTS A total of 59 patients were available at the 3-year follow-up; 32 patients with a monolithic zirconia crown (TEST) and 27 patients with a porcelain-fused-to-metal crown (CONTROL). 14 implants (11 implant fractures/3 aseptic losses) were lost leading to an estimated implant survival rate of 80% ± 5.1% (95% CI 70.8%-90.8%). Prosthetic complications were limited to the control group and involved minor chippings. CONCLUSIONS This type of reduced-diameter implant to support single implant molar crowns in the molar area cannot be recommended. Monolithic zirconia crowns appear to be a viable option in the posterior region showing similar prosthetic outcomes to porcelain-fused-to-metal crowns.
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Affiliation(s)
- K Zumstein
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - T Waller
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - C H F Hämmerle
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - R E Jung
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - G Benic
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - S Mühlemann
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
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Alghazzawi TF. A Comparison of Failure Loads for Polycrystalline Zirconia Ceramics with Varying Amounts of Yttria, Glass-Ceramics and Polymers in Two Different Test Conditions. Polymers (Basel) 2023; 15:4506. [PMID: 38231917 PMCID: PMC10708478 DOI: 10.3390/polym15234506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/14/2023] [Accepted: 11/21/2023] [Indexed: 01/19/2024] Open
Abstract
It is unclear how zirconia dental crowns with different yttria compositions will perform clinically, and how they will compare with crowns made of glass-ceramics and polymers. The present objective was to determine failure loads of crowns and discs made of glass ceramics or polymers as compared to yttria-partially stabilized zirconia (Y-PSZ) crowns and discs with varying yttria concentrations. Crowns of zirconia (Cercon XT, Katana UTML, BruxZir Anterior), glass ceramic (Celtra press, IPS e.max press, Lisi press), and polymeric materials (Trilor, Juvora, Pekkton) were fabricated and cemented to epoxy abutments. The total number of specimens was 135 for crowns and 135 for discs (n = 15 specimens per material type and design). A universal testing machine was used to perform compressive loading of crowns/discs to failure with a steel piston along the longitudinal axis of the abutments. Energy dispersive spectroscopy (EDS) was used to identify the yttria concentration for each zirconia brand. The data were analyzed using generalized linear models and regression analyses. The results revealed significant differences (p < 0.05) in mean failure loads for different crown materials: Trilor (6811 ± 960 N) > Juvora (5215 ± 151 N) > Cercon (4260 ± 520 N) = BruxZir (4186 ± 269 N) = e.max (3981 ± 384 N) > Katana (3195 ± 350 N) = Lisi (3173 ± 234 N) = Pekkton (3105 ± 398 N) > Celtra (2696 ± 393 N). The general linear model revealed significant differences (p < 0.05) in mean failure loads when comparing the different materials for the discs, i.e., Trilor (5456 ± 1748 N) > Juvora (4274 ± 869 N) > Pekkton (3771 ± 294 N) > Katana (2859 ± 527 N) > Cercon (2319 ± 342 N) = BuxZir (2250 ± 515 N) = e.max (2303 ± 721 N) = Lisi (2333 ± 535 N) > Celtra (1965 ± 659 N). EDS showed that the zirconia materials contained yttria at different concentrations (BruxZir = 5Y-PSZ, Cercon = 4Y-PSZ, Katana = 3Y-PSZ). The yttria concentration had a significant effect on the failure load of the Katana (3Y-PSZ) crowns, which revealed lower failure loads than the Cercon (4Y-PSZ) and BruxZir (5Y-PSZ) crowns, whose failure loads were comparable or higher than e.max glass ceramic. The failure load of the trilayer disc specimens did not correlate with the failure load of the respective crown specimens for the zirconia, glass-ceramic and polymeric materials.
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Affiliation(s)
- Tariq F. Alghazzawi
- Department of Substitutive Dental Sciences, Taibah University, Madinah 42353, Saudi Arabia;
- Department of Mechanical and Materials Engineering, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
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16
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Giugliano TS, Zhang Y, Janal MN, Lim CH, Smith RM, Choi M. In vitro comparison of physical characteristics of milled versus printed zirconia discs. J Prosthodont 2023:10.1111/jopr.13778. [PMID: 37776103 PMCID: PMC10980599 DOI: 10.1111/jopr.13778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/25/2023] [Accepted: 09/27/2023] [Indexed: 10/01/2023] Open
Abstract
PURPOSE The purpose of this study was to compare the dimensional accuracy, translucency, and biaxial flexural strength of milled zirconia (MZ) versus 3D-printed zirconia (PZ) discs. MATERIALS & METHODS A circular disc measuring 14.0 mm in diameter and 1.20 mm in thickness was designed using computer-aided design (CAD) software. The resulting standard tessellation language (STL) file was used both as a control and to fabricate 36 zirconia (3Y-TZP) disc specimens (n = 36): 18 were milled (group MZ) and 18 were 3D-printed (group PZ). The diameter and thickness of each disc were measured using a digital caliper. Translucency was evaluated using a calibrated dental colorimeter. The flexural strength was determined using the piston-on-three-ball biaxial flexure test. All measurements were done by one blinded examiner. The statistical significance level was set to α = 0.05. RESULTS The MZ discs had significantly more accurate dimensions than the PZ discs in both diameter and thickness when compared to the control CAD software-designed disc. The MZ discs exhibited significantly higher translucency (translucency parameter (TP) = 16.95 ±0.36 vs. 9.24 ±1.98) and biaxial flexural strength (996.16 ±137.37 MPa vs. 845.75 ±266.16 MPa) than the PZ discs. Finally, MZ possessed a significantly higher Weibull modulus relative to PZ. CONCLUSIONS The results showed that the milled specimens achieved better dimensional accuracy and were more translucent, stronger, and less prone to failure than printed specimens.
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Affiliation(s)
- Thomas S. Giugliano
- Department of Prosthodontics, New York University College of Dentistry, New York, NY
| | - Yu Zhang
- Laboratories for Microstructure Physics & Mechanics of Materials, Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA
| | - Malvin N. Janal
- Department of Epidemiology & Health Promotion, New York University College of Dentistry, New York, NY
| | - Chek Hai Lim
- Laboratories for Microstructure Physics & Mechanics of Materials, Department of Preventive and Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA
| | - Ruby M. Smith
- Post-Graduate Student, Department of Prosthodontics, New York University College of Dentistry, New York, NY
| | - Mijin Choi
- Department of Prosthodontics, New York University College of Dentistry, New York, NY
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17
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Mahat NS, Shetty NY, Kohli S, Jamayet NB, Patil P. Clinical outcomes of implant-supported and tooth-supported fixed prostheses fabricated from digital versus analogue impression: a systematic review and meta-analysis. Evid Based Dent 2023; 24:142. [PMID: 37369705 DOI: 10.1038/s41432-023-00904-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/15/2023] [Indexed: 06/29/2023]
Abstract
OBJECTIVE To analyze the clinical outcomes of implant-supported prostheses and tooth-supported fixed prostheses, fabricated from digital and conventional impression. MATERIALS AND METHODS The literature search was carried out on two electronic databases (PubMed and Cochrane Library). Randomized controlled trials (RCT) published from January 2011 to September 2022 were included. The bias risk was evaluated using Cochrane Risk of Bias Tool 2.0. Further screening was done for meta-analysis according to modified Newcastle-Ottawa scoring criteria. Forest plot was generated using a statistical method of inverse variance of random effect with 95% confidence interval. RESULTS A total of 8 randomized controlled trials were included for systematic review out of which four studies were based on tooth-supported fixed prosthesis and remaining four were based on implant-supported prosthesis. Further screening was conducted and three studies were eligible for meta-analysis. Tooth-supported fixed prosthesis fabricated from digital impression showed no significant difference in the marginal fit in any region measured, except for occlusal region where conventional impression showed more favorable marginal fit. Implant-supported prosthesis fabricated from digital impression showed survival rates ranging from 97.3 to 100% and there was no statistically significant difference in marginal bone loss (p = 0.14). CONCLUSION Implant-supported prostheses fabricated from digital and conventional impressions show no significant differences in their clinical outcomes. Tooth-supported fixed prostheses fabricated from digital impression have shown favorable findings in terms of marginal fit. Despite that, there is still lack of clinical trials with larger sample size and longer follow-up periods. Future studies that fulfill these two criteria are deemed necessary.
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Affiliation(s)
- Nur Safiani Mahat
- School of Dentistry, International Medical University, Kuala Lumpur, Malaysia
| | - Naresh Yedthare Shetty
- Associate Professor, Department of Clinical Sciences, Ajman University, Ajman, UAE
- Centre of Medical and Biomedical Allied Health Sciences Research, Deanship of Graduate Studies and Research, Ajman, UAE
| | - Shivani Kohli
- Senior Lecturer, Division of Restorative Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia.
| | - Nafij Bin Jamayet
- Senior Lecturer, Division of Restorative Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia
| | - Pravinkumar Patil
- Associate Professor, Division of Restorative Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia
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18
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Ioannidis A, Pala K, Strauss FJ, Hjerppe J, Jung RE, Joda T. Additively and subtractively manufactured implant-supported fixed dental prostheses: A systematic review. Clin Oral Implants Res 2023; 34 Suppl 26:50-63. [PMID: 37750533 DOI: 10.1111/clr.14085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/24/2023] [Accepted: 04/26/2023] [Indexed: 09/27/2023]
Abstract
AIM To compare and report on the performance of implant-supported fixed dental prostheses (iFDPs) fabricated using additive (AM) or subtractive (SM) manufacturing. METHODS An electronic search was conducted (Medline, Embase, Cochrane Central, Epistemonikos, clinical trials registries) with a focused PICO question: In partially edentulous patients with missing single (or multiple) teeth undergoing dental implant therapy (P), do AM iFDPs (I) compared to SM iFDPs (C) result in improved clinical performance (O)? Included were studies comparing AM to SM iFDPs (randomized clinical trials, prospective/retrospective clinical studies, case series, in vitro studies). RESULTS Of 2'184 citations, no clinical study met the inclusion criteria, whereas six in vitro studies proved to be eligible. Due to the lack of clinical studies and considerable heterogeneity across the studies, no meta-analysis could be performed. AM iFDPs were made of zirconia and polymers. For SM iFDPs, zirconia, lithium disilicate, resin-modified ceramics and different types of polymer-based materials were used. Performance was evaluated by assessing marginal and internal discrepancies and mechanical properties (fracture loads, bending moments). Three of the included studies examined the marginal and internal discrepancies of interim or definitive iFDPs, while four examined mechanical properties. Based on marginal and internal discrepancies as well as the mechanical properties of AM and SM iFDPs, the studies revealed inconclusive results. CONCLUSION Despite the development of AM and the comprehensive search, there is very limited data available on the performance of AM iFDPs and their comparison to SM techniques. Therefore, the clinical performance of iFDPs by AM remains to be elucidated.
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Affiliation(s)
- Alexis Ioannidis
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Kevser Pala
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Franz J Strauss
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Jenni Hjerppe
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Ronald E Jung
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Tim Joda
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
- Department of Reconstructive Dentistry, University Center for Dental Medicine Basel, University of Basel, Basel, Switzerland
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19
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Chantler JGM, Evans CDJ, Zitzmann NU, Derksen W. Clinical performance of single implant prostheses restored using titanium base abutments: A systematic review and meta-analysis. Clin Oral Implants Res 2023; 34 Suppl 26:64-85. [PMID: 37750524 DOI: 10.1111/clr.14128] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 06/16/2023] [Accepted: 06/21/2023] [Indexed: 09/27/2023]
Abstract
PURPOSE The aim of this review was to evaluate the survival rates of restorations utilizing titanium base abutments (TBA) for restoring single-unit implant prostheses. MATERIALS AND METHODS This review was conducted following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The focus question was: In patients who require the restoration of a single dental implant utilizing a titanium base abutment, what are the determining factors and outcomes relating to implant prosthesis prognosis and survival? A comprehensive search of databases (PubMed, EMBASE, and Cochrane Library) was conducted on 16 April 2023 and updated on 5 May 2023. Randomized clinical trials (RCT), retrospective studies and prospective studies, reporting on the use of TBA for single implant prostheses, were reviewed. A Cochrane collaboration risk of bias assessment analysis was performed for randomized clinical studies, and the Newcastle-Ottawa Scale tool was applied for non-randomized studies. A meta-analysis was performed on clinical trials reporting on survival rates of both TBA and other abutments. Other clinical studies, reporting on TBA only, were included for descriptive statistics. RESULTS The search provided 1159 titles after duplicates were removed. Six RCTs were included to perform a meta-analysis and compare the survival of the TBA to other abutments [OR 0.74; 95% CI: 0.21-2.63, heterogeneity; I2 0%; p = .99]. Twenty-three prospective and retrospective studies fulfilled the criteria and were included in the meta-analysis after 12 months of function. A total of 857 single implant-supported prostheses fabricated with a TBA were included. TBA abutments have an estimate 98.6% survival rate after 1 year in function (95% CI: 97.9%-99.4%). The mean follow-up period was 31.2 ± 16.9 months. CONCLUSIONS Single implant prosthesis restored with titanium base abutments showed favourable short-term survival rates.
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Affiliation(s)
| | | | - Nicola U Zitzmann
- Department of Reconstructive Dentistry, University of Basel, Basel, Switzerland
| | - Wiebe Derksen
- Department of Oral Implantology and Prosthetic Dentistry, Amsterdam, Netherlands
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Graf T, Schweiger J, Stimmelmayr M, Erdelt K, Schubert O, Güth JF. Influence of monolithic restorative materials on the implant-abutment interface of hybrid abutment crowns: An in vitro investigation. J Prosthodont Res 2023; 67:450-459. [PMID: 36517017 DOI: 10.2186/jpr.jpr_d_22_00115] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
Purpose This in vitro study aimed to investigate the long-term performance, stability, and fracture mode of monolithic hybrid abutment crowns, and the effect of different materials on the implant-abutment interface (IAI).Methods Eighty monolithic hybrid abutment crowns luted on titanium bases were manufactured from 3Y-TZP zirconia (ZY3), "Gradient Technology" zirconia (ZY35), 5Y-TZP zirconia (ZY5), lithium disilicate ceramic (LDS), zirconia-reinforced lithium silicate ceramic (ZLS), polymer-infiltrated ceramic network (MHY), polymethylmethacrylate (PMA), and 3D-printed hybrid composite (PHC) (n = 10 for each material). Eighty implants (Camlog Progressive-Line, diameter: 3.8 mm) were embedded in accordance with ISO standard 14801, and crowns were mounted. After artificial aging (1.2 × 106 cycles, 50 N, thermocycling), intact specimens were loaded 30° off-axis in a universal testing machine until failure.Results Seven specimens in the PHC group failed during artificial aging, and all the others survived. There were two subgroups based on the one-way analysis of variance and Dunnett's test (P < 0.05) of the mean fracture load values. The first comprised Z3Y, ZY35, Z5Y, and LDS, with mean fracture loads between 499.4 and 529.7 N, while the second included ZLS, MHY, and PMA, with values in the 346.2-416.0 N range. ZY3, ZY35, ZY5, and LDS exhibited irreversible, visible deformations of the implant shoulders with varying dimensions after load-to-fracture tests.Conclusions Crowns made of LDS, ZLS, MHY, and PMA may act as potential stress breakers, and prevent possible deformation at IAIs. Further clinical studies need to assess if these materials also withstand relevant loads in-vivo.
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Affiliation(s)
- Tobias Graf
- Department of Prosthodontics, Center for Dentistry and Oral Medicine (Carolinum), Goethe University Frankfurt am Main, Germany
| | - Josef Schweiger
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Germany
| | - Michael Stimmelmayr
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Germany
| | - Kurt Erdelt
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Germany
| | - Oliver Schubert
- Department of Prosthetic Dentistry, University Hospital, LMU Munich, Germany
| | - Jan-Frederik Güth
- Department of Prosthodontics, Center for Dentistry and Oral Medicine (Carolinum), Goethe University Frankfurt am Main, Germany
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Cao R, Chen B, Xu H, Fan Z. Clinical outcomes of titanium-zirconium alloy narrow-diameter implants for single-crown restorations: a systematic review and meta-analysis. Br J Oral Maxillofac Surg 2023; 61:403-410. [PMID: 37331853 DOI: 10.1016/j.bjoms.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 02/26/2023] [Accepted: 05/07/2023] [Indexed: 06/20/2023]
Abstract
Evidence is limited on whether titanium-zirconium alloy, narrow-diameter implants (Ti-Zr NDIs) have promising clinical outcomes when used to support single crowns. The purpose of this systematic review and meta-analysis was to evaluate clinical evidence, including survival rates, success rates, and marginal bone loss (MBL) on Ti-Zr NDIs that support single crowns. An extensive search was performed in the databases of PubMed/MEDLINE, Scopus, Embase, and the Cochrane Library for studies published in English up to April 2022. Only peer-reviewed clinical studies with at least 10 patients and a follow-up time of at least 12 months were included. Risk of bias in each study was assessed and data extraction was carried out independently by two reviewers. The outcome variables were survival rates, success rates, and MBL. The search returned 779 results. Eight studies were identified for qualitative analysis and seven for quantitative synthesis. Overall, a total of 256 Ti-Zr NDIs were included. Cumulative implant survival rates and success rates were 97.5% (95% confidence interval (CI): 94.5% to 98.9%) and 97.2% (95% CI: 94.2% to 98.7%), respectively, over a maximum follow-up period of 36 months, with no difference between Ti-Zr NDIs and commercial pure titanium (cpTi) implants. Cumulative mean (SD) MBL was 0.44 (0.04) mm (95% CI: 0.36 to 0.52) after one year. Meta-analysis of MBL indicated a mean difference of 0.02 mm (95% CI: -0.23 to 0.10), with no differences between Ti-Zr NDIs and cpTi implants. Short-term results of Ti-Zr NDIs for single-crown restorations are quite promising, although the number of published studies and follow-up periods are insufficient to determine the real benefit for single crowns. Long-term, follow-up clinical studies are needed to verify the excellent clinical performance of Ti-Zr NDIs.
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Affiliation(s)
- Rongkai Cao
- School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, PR China
| | - Beibei Chen
- School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, PR China
| | - Hui Xu
- School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, PR China
| | - Zhen Fan
- Department of Oral Implantology, School & Hospital of Stomatology, Tongji University, Shanghai Engineering Research Center of Tooth Restoration and Regeneration, Shanghai, PR China.
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Tajti P, Solyom E, Czumbel LM, Szabó B, Fazekas R, Németh O, Hermann P, Gerber G, Hegyi P, Mikulás K. Monolithic zirconia as a valid alternative to metal-ceramic for implant-supported single crowns in the posterior region: A systematic review and meta-analysis of randomized controlled trials. J Prosthet Dent 2023:S0022-3913(23)00336-0. [PMID: 37349158 DOI: 10.1016/j.prosdent.2023.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 06/24/2023]
Abstract
STATEMENT OF PROBLEM Technical complication rates of standard metal-ceramic implant-supported posterior restorations are relatively high. Whether monolithic zirconia crowns represent a more successful alternative is unclear. PURPOSE The purpose of this systematic review and meta-analysis was to compare the clinical outcomes of posterior monolithic zirconia and metal-ceramic implant-supported single crowns. MATERIAL AND METHODS A search was conducted in MEDLINE, Scopus, Embase, Web of Science, and CENTRAL databases for randomized controlled trials up to April 2023 with a follow-up time of at least 1 year. Restoration and implant survival and failure rates, marginal bone loss (MBL), bleeding on probing (BOP), and technical complications were analyzed by 2 reviewers. Statistical analyses were conducted using the R-statistics software program. The risk of bias was assessed by the Cochrane Risk of Bias Tool 2 (RoB 2), and the certainty of evidence by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. RESULTS A total of 11 out of 2030 records were identified by title and abstract, and 4 records were included after full-text analysis. The statistical analysis revealed no significant difference in MBL (MD -0.11, 95% CI: [-0.25; 0.03]), BOP (OR 0.66, 95% CI: [0.25; 1.77]), or implant failure (OR 1.30, 95% CI: [0.24; 7.08]). Monolithic zirconia presented significantly less chipping over 1 year (OR 0.17, 95% CI: [0.03; 0.99]). The chipping rate was 0% for monolithic zirconia and 7.61% for metal-ceramic. Based on a narrative review, the restoration survival rate was 97.5% in the monolithic zirconia group and 99.1% in the metal-ceramic group. CONCLUSIONS Monolithic zirconia showed favorable short-term survival rates and had significantly less chipping over 1 year. Regarding MBL, BOP, and failure rates, both restoration types presented similar results at the 1-year follow-up.
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Affiliation(s)
- Péter Tajti
- Resident, Department of Prosthodontics, Semmelweis University, Budapest, Hungary; PhD student, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Eleonora Solyom
- Clinical Specialist, Department of Periodontology, Semmelweis University, Budapest, Hungary; PhD student, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - László Márk Czumbel
- Resident, Department of Periodontology, Semmelweis University, Budapest, Hungary; Scientific Methodology Supervisor, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Bence Szabó
- Biostatistician, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Réka Fazekas
- Assistant Professor, Department of Conservative Dentistry, Semmelweis University, Budapest, Hungary; Supervisor, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Orsolya Németh
- Director, Associate Professor, Department of Community Dentistry, Semmelweis University, Budapest, Hungary; Supervisor, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Péter Hermann
- Director, Full Professor, Department of Prosthodontics, Semmelweis University, Budapest, Hungary; Supervisor, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Gábor Gerber
- Associate Professor, Department of Anatomy, Histology and Embryology, Semmelweis University, Budapest, Hungary; Supervisor, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary
| | - Péter Hegyi
- Strategic Director, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary; Strategic Director, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - Krisztina Mikulás
- Assistant Professor, Department of Prosthodontics, Semmelweis University, Budapest, Hungary; Supervisor, Centre for Translational Medicine, Semmelweis University, Budapest, Hungary.
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Rues S, Zehender N, Zenthöfer A, Bömicke W, Herpel C, Ilani A, Erber R, Roser C, Lux CJ, Rammelsberg P, Schwindling FS. Fit of anterior restorations made of 3D-printed and milled zirconia: An in-vitro study. J Dent 2023; 130:104415. [PMID: 36640843 DOI: 10.1016/j.jdent.2023.104415] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 12/23/2022] [Accepted: 01/10/2023] [Indexed: 01/13/2023] Open
Abstract
OBJECTIVES To evaluate the fit of zirconia veneers made by either 3D printing or milling. METHODS A typodont maxillary central incisor was prepared for a 0.5-mm-thick veneer and was reproduced 36 times from resin. Restorations were designed with a 20-µm-wide marginal and a 60-µm-wide internal cement gap, and were made from 3D-printed zirconia (LithaCon 3Y 210, Lithoz, n = 24) and milled zirconia (Cercon ht, DentsplySirona, n = 12). For milled zirconia, a drill compensation was needed to give the milling bur access to the intaglio surface. The restorations were cemented, cross-sectioned, and the cement gap size was analyzed by two raters. Inter-rater reliability was studied at 12 3D-printed veneers (intraclass correlation coefficient, ICC, mixed model, absolute agreement). Twelve remaining 3D-printed restorations were compared with 12 milled restorations regarding fit at three locations: marginally, labially, and at the incisal edge (Mann-Whitney U-tests, α<0.05). RESULTS Inter-rater reliability was excellent, with an ICC single-measure coefficient of 0.944 (95%-confidence interval: [0.907; 0.966]). Gap sizes (mean ± SD / maximum) were 55 ± 9 / 143 µm at the margins, 68 ± 14 / 130 µm labially, and 78 ± 19 / 176 µm at the incisor edge for 3D-printed veneers. For milled veneers, gap sizes were 44 ± 11 / 141 µm at the margins, 85 ± 19 / 171 µm labially, and 391 ± 26 / 477 µm at the incisor edge. At the margins, the milled veneers outperformed the 3D-printed restorations (p = 0.011). The cement gap at the incisor edge was significantly smaller after 3D printing (p < 0.001). CONCLUSIONS 3D-printed zirconia restorations showed clinically acceptable mean marginal gaps below 100 µm. Because drill compensation could be omitted with 3D printing, the fit at the sharp incisal edge was significantly tighter than with milling. CLINICAL SIGNIFICANCE The fit of 3D-printed ceramic anterior restorations meets clinical standards. In addition, 3D printing is associated with a greater geometrical freedom than milling. With regard to fit this feature allows tighter adaptation even after minimally invasive preparation.
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Affiliation(s)
- Stefan Rues
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Nathalie Zehender
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Andreas Zenthöfer
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Wolfgang Bömicke
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Christopher Herpel
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Ali Ilani
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Ralf Erber
- Department of Orthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Christoph Roser
- Department of Orthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Christopher J Lux
- Department of Orthodontics, Heidelberg University Hospital, Heidelberg, Germany
| | - Peter Rammelsberg
- Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany
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Kim W, Li XC, Bidra AS. Clinical outcomes of implant-supported monolithic zirconia crowns and fixed partial dentures: A systematic review. J Prosthodont 2023; 32:102-107. [PMID: 35929416 DOI: 10.1111/jopr.13575] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 07/25/2022] [Indexed: 11/30/2022] Open
Abstract
PURPOSE To determine the survival rates of implant-supported monolithic zirconia crowns and fixed partial dentures (FPD). MATERIAL AND METHODS An electronic search for articles in the English language literature published from January 1, 2001 to September 17, 2021 was performed using PubMed, Scopus, and CENTRAL search engines. After applying predetermined inclusion and exclusion criteria, the definitive list of selected articles was used for calculating the interval survival rate (ISR) and cumulative survival rate (CSR). Restoration failure in this study was defined as the fracture or compromise of any part of the ceramic restoration that required the removal or remake of the implant-supported restoration. RESULTS The electronic search resulted in 457 titles. The systematic application of inclusion and exclusion criteria resulted in 14 clinical studies that addressed the clinical outcomes of implant-supported monolithic zirconia crowns and fixed partial dentures. Of these, 3 were randomized controlled trials, 5 were prospective studies, and 6 were retrospective studies. Follow-up periods ranged from 1 to 5 years. Of the 644 implant-supported monolithic zirconia restorations computed in this systematic review, there was only 1 reported failure of the monolithic zirconia restorative material over a follow-up period of up to 5 years, for a cumulative survival rate of 99.84%. At the maximum follow-up interval of 5 years, the cumulative survival rate for monolithic zirconia single crowns was 100% and the cumulative survival rate for monolithic zirconia fixed partial dentures was 99.60%. CONCLUSIONS Implant-supported monolithic zirconia single crowns and fixed partial dentures have excellent short-term (<5 years) survival rates but the evidence for medium-term survival (>5 years) and beyond is lacking.
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Affiliation(s)
- Wanjin Kim
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
| | - Xiao Chun Li
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
| | - Avinash S Bidra
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT
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Lampl S, Gurunathan D, Krithikadatta J, Mehta D, Moodley D. Reasons for Failure of CAD/CAM Restorations in Clinical Studies: A Systematic Review and Meta-analysis. J Contemp Dent Pract 2023; 24:129-136. [PMID: 37272145 DOI: 10.5005/jp-journals-10024-3472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
AIM The systematic review presented herein was performed to descriptively analyze the causes for the failure of computer-aided design/computer-aided manufacture (CAD/CAM) restorations. The meta-analysis reported herein was performed to estimate long-term survival and success rates of CAD-CAM fabrications. MATERIALS AND METHODS Using the PICOS paradigm, a systematic search was carried out in the PubMed and Cochrane databases to identify randomized controlled trials (RCTs) and prospective observational studies reporting survival data for CAD/CAM restorations. After selecting studies with a predefined set of selection criteria, data from included prospective clinical studies and RCTs were used for a systematic review aimed at a descriptive analysis of factors associated with failure of CAD-CAM restorations. Data from the included prospective clinical studies were used for meta-analysis, wherein 5-year and 10-year survival and success rates were estimated using Poisson regression models. RESULTS The systematic review included data from 9 RCTs and 6 observational studies, which had a median follow-up of 36 months and 60 months, respectively. About 58 failures and 118 technical/ biological complications were noted in the included RCTs and 9 failures along with 58 technical/biological complications were noted in the prospective clinical studies. Poisson regression indicated an estimated 5-year and 10-year survival rates of 85.55-100 and 71-100, respectively. The estimated 5-year and 10-year success rates were 74.2-92.75 and 33.3-85.5, respectively. CONCLUSION Several technical and biological complications contribute to failure of CAD/CAM restorations. However, CAD/CAM restorations with routine chairside materials might have clinically meaningful success rates in the long term. CLINICAL SIGNIFICANCE The results presented herein indicate that optimal strategies for mitigation of biological and technical complications may augment the success of CAD/CAM fabrications in restorative dentistry. Studies aimed at identification of such strategies are needed to further enhance the long-term success rates of CAD/CAM restorations.
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Affiliation(s)
- Stephan Lampl
- Department of Paediatric Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India
| | - Deepa Gurunathan
- Department of Paediatric Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India, Phone: +91 9994619386, e-mail:
| | - Jogikalmat Krithikadatta
- Department of Paediatric Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India
| | - Deepak Mehta
- Department of Conservative Dentistry, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Chennai, India; Department of Operative Dentistry, Tohoku University Graduate School of Dentistry, Tohoku University, Sendai, Japan
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Lemos CAA, Verri FR, de Luna Gomes JM, Santiago Junior JF, Miyashita E, Mendonça G, Pellizzer EP. Survival and prosthetic complications of monolithic ceramic implant-supported single crowns and fixed partial dentures: A systematic review with meta-analysis. J Prosthet Dent 2022:S0022-3913(22)00736-3. [PMID: 36564291 DOI: 10.1016/j.prosdent.2022.11.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 11/15/2022] [Accepted: 11/15/2022] [Indexed: 12/24/2022]
Abstract
STATEMENT OF PROBLEM Monolithic ceramic implant-supported restorations have been used to rehabilitate partially edentulous patients. However, knowledge of the survival and prosthetic complications of single crowns (SCs) and fixed partial dentures (FPDs) is limited. PURPOSE The purpose of this systematic review with meta-analysis was to evaluate the clinical performance of monolithic ceramic implant-supported SCs and FPDs in terms of survival and prosthetic complication rates. MATERIAL AND METHODS The systematic review was registered on the prospective register of systematic reviews (PROSPERO) (CRD42017078568). Five electronic databases were independently searched by 2 authors for articles published until May 2022. In addition, a hand search was performed in the nonpeer-reviewed literature, specific journals, and reference lists of included articles. A single-arm meta-analysis was performed by using the R program. The risk of bias and quality were assessed using the Cochrane risk of bias tools and the Newcastle-Ottawa scale. RESULTS Twenty-eight studies were included in the quantitative synthesis. A total of 1298 monolithic ceramic implant-supported restorations (1116 SCs and 182 FPDs) were evaluated in 1193 participants, with a median observation time of 24 months (range: 12 to 72 months). Meta-analysis indicated the proportion of failures and prosthetic complication rates of 2% (95% confidence interval [CI]: 1% to 4%) for SCs. No difference was observed for monolithic zirconia and lithium disilicate SCs. In the FPDs, only monolithic zirconia was considered, with 1 failure reported totaling the proportion of failures of 0% (0% to 1%) and complication rates of 4% (0% to 12%). The most complications reported for both types of restorations were screw loosening, debonding, and minor chipping and were considered repairable. The included studies showed a low risk of bias and good quality. CONCLUSIONS The use of monolithic ceramic implant-supported SCs, independent of ceramic material, and monolithic zirconia implant-supported FPDs should be considered an effective and safe treatment option because of favorable short-term survival and low prosthetic complications. However, additional well-conducted studies with a longer-term follow-up and direct comparison between veneered restorations are recommended to reassess clinical performance.
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Affiliation(s)
- Cleidiel Aparecido Araujo Lemos
- Adjunct Professor, Department of Dentistry, Federal University of Juiz de Fora - Campus Governador Valadares (UFJF/GV), Governador Valadares, Minas Gerais, Brazil.
| | - Fellippo Ramos Verri
- Adjunct Professor, Departament of Dental Materials and Prosthodontics, São Paulo State Univeristy (UNESP), Araçatuba Dental School, Araçatuba, São Paulo, Brazil
| | | | - Joel Ferreira Santiago Junior
- Professor, Departament of Health Sciences, School of Dentistry, Centro Universitário Sagrado Coração-UNISAGRADO, Bauru, São Paulo, Brazil
| | - Eduardo Miyashita
- Titular Professor, Department of Dentistry, UNIP - Universidade Paulista, São Paulo, Brazil
| | - Gustavo Mendonça
- Clinical Associate Professor, Department of Biological and Material Sciences, School of Dentistry, University of Michigan, Ann Arbor, Mich
| | - Eduardo Piza Pellizzer
- Titular Professor, Department of Dental Materials and Prosthodontics, Sao Paulo State University (UNESP), Araçatuba, Brazil
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Abualsaud R, Alalawi H. Fit, Precision, and Trueness of 3D-Printed Zirconia Crowns Compared to Milled Counterparts. Dent J (Basel) 2022; 10:dj10110215. [PMID: 36421402 PMCID: PMC9689223 DOI: 10.3390/dj10110215] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/08/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022] Open
Abstract
Precise fit of a crown and accurate reproduction of the digital design are paramount for successful treatment outcomes and preservation of clinician and technician time. The study aimed to compare the internal fit, marginal adaptation, precision, and trueness of 3D-printed zirconia crowns compared to their milled counterpart. A total of 20 monolithic 3 mol% yttria stabilized-zirconia crowns (n = 10) were made using computer-assisted design (CAD) followed by additive (3D-printed) and subtractive (milled) manufacturing. Digital scanning of the master die with and without a fit checker followed by image superimposition, and analysis was performed to evaluate internal and marginal adaptation in four areas (occlusal, axial, marginal, and overall). ISO 12836:2015 standard was followed for precision and trueness evaluation. Statistical analysis was achieved using a t-test at α = 0.05. Internal fit and marginal adaptation revealed no significant difference between the two test groups (p > 0.05). The significant difference in trueness (p < 0.05) was found between the two groups in three areas (occlusal, axial, and internal). The best and worst trueness values were seen with 3D-printed crowns at occlusal (8.77 ± 0.89 µm) and Intaglio (23.90 ± 1.60 µm), respectively. The overall precision was statistically better (p < 0.05) in the 3D-printed crowns (9.59 ± 0.75 µm) than the milled (17.31 ± 3.39 µm). 3D-printed and milled zirconia crowns were comparable to each other in terms of internal fit and marginal adaptation. The trueness of the occlusal and axial surfaces of 3D-printed crowns was better, whereas the trueness of fitting surface of milled crowns was better. 3D-printed crowns provided a higher level of precision than milled crowns. Although the internal and marginal fit of both production techniques were comparable, 3D printing of zirconia produced more precise crowns.
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Abstract
Resin-bonded ceramic restorations are common treatment options. Clinical longevity of resin-bonded ceramic restorations depends on the quality and durability of the resin-ceramic bond. The type and composition of the specific ceramic determines the selection of the most effective bonding protocol. Such protocol typically includes a surface pretreatment step followed by application of a priming agent. Understanding of fundamental ceramic properties and chemical compositions enables the clinician to make proper material selection decisions for clinically successful and long-lasting restorations. Based on research accrued over the past decades, this article reviews and discusses current resin-bonding protocols to most commonly used dental ceramics.
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Affiliation(s)
- Markus B Blatz
- Department of Preventive and Restorative Sciences, University of Pennsylvania School of Dental Medicine, 240 South 40th Street, Philadelphia, PA 19104, USA.
| | - Julian Conejo
- Department of Preventive and Restorative Sciences, University of Pennsylvania School of Dental Medicine, 240 South 40th Street, Philadelphia, PA 19104, USA
| | - Amirah Alammar
- Sijam Medical Center, Northern Ring Road, Alghadeer District, Riyadh, Saudi Arabia
| | - Jose Ayub
- Department of Preventive and Restorative Sciences, University of Pennsylvania School of Dental Medicine, 240 South 40th Street, Philadelphia, PA 19104, USA
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Abduo J, Lau D. Proximal contact loss between implant prostheses and adjacent natural teeth: a qualitative systematic review of prevalence, influencing factors and implications. Heliyon 2022; 8:e10064. [PMID: 35992004 PMCID: PMC9382270 DOI: 10.1016/j.heliyon.2022.e10064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 03/13/2022] [Accepted: 07/19/2022] [Indexed: 11/05/2022] Open
Abstract
Objectives To evaluate the prevalence of proximal contact loss (PCL) between implant prostheses and natural teeth, and identify the risk factors and implications associated with PCL. Data/sources PubMed (MEDLINE), Google Scholar, Cochrane Library Database, Scopus, EMBASE, Open Grey, ScienceDirect, and Web of Science were electronically searched to retrieve clinical studies on PCL around implant prostheses up to September 2021. Study selection A total of 19 studies were eligible. The short-term studies (less than 2 years) revealed a PCL prevalence of 11–30%, the medium-term studies (2–5 years) indicated a PCL prevalence of 13–65%, and the long-term studies (more than 5 years) showed a PCL prevalence of 29–83.3%. The likely influencing factors were the duration of service and the mesial location of proximal contacts. Other factors, such as occlusion, vitality of adjacent teeth, implant location, patient age and splinting had a less obvious relation to PCL. The reported implications of PCL were food impaction and patient dissatisfaction. Bone loss, peri-implant inflammation, bleeding on probing and pocket depth had a less clear association with PCL. Conclusions PCL development between implant prostheses and natural teeth is frequent, inevitable and progressive. While the review identified several influencing factors and implications of PCL, future research is needed to outline the influence of prosthesis design on PCL and food impaction. Clinical significance Patients with implant prostheses should be informed about PCL likelihood and the risk of food impaction around implant prostheses. The proximal contact quality and its implications should be monitored during the review visits.
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de Araújo-Júnior ENS, Bergamo ETP, Bastos TMC, Benalcázar Jalkh EB, Lopes ACO, Monteiro KN, Cesar PF, Tognolo FC, Migliati R, Tanaka R, Bonfante EA. Ultra-translucent zirconia processing and aging effect on microstructural, optical, and mechanical properties. Dent Mater 2022; 38:587-600. [PMID: 35272865 DOI: 10.1016/j.dental.2022.02.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 12/15/2022]
Abstract
OBJECTIVES To evaluate the effect of the ceramic processing and aging method on the microstructure, optical, and mechanical properties of a third generation ultra-translucent zirconia, yttria partially stabilized zirconia (5Y-PSZ). METHODS In-house discs were obtained through uniaxial and isostatic pressing an ultra-translucent Y-PSZ powder and sintering at 1450 °C for 2 h. As control, a commercial disc was milled from pre-sintered blocks fabricated with the same 5Y-PSZ powder through isostatic pressing and sintered under the same protocol. Discs were allocated into three groups according to aging condition as immediate (non-aged) and aged using autoclave or hydrothermal reactor at 134ºC for 20 h at 2.2 bar. Crystalline content and microstructure were evaluated using X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Optical properties were determined using reflectance data to calculate the contrast ratio (CR) and translucency parameter (TP). Mechanical properties were assessed by Vickers hardness, fracture toughness and biaxial flexural strength tests. RESULTS XRD spectra revealed a prevalence of cubic (70%) and tetragonal (30%) phases, and the SEM images showed a dense fully crystalline ceramic matrix for both materials. Crystalline content and microstructure of the in-house and commercial 5Y-PSZs were not affected by aging. As-sintered 5Y-PSZs demonstrated similar CR (~0.6) and TP (~18) values, as well as Vickers hardness (~14 GPa) and fracture toughness (~3.8 Mpa.m1/2), with no significant alteration after both aging methods. In-house and commercial Y-PSZs Weibull moduli ranged from 3.0 to 5.3. 5Y-PSZ processing methods resulted in similar characteristic strength after sintering (592-618 Mpa). While commercial 5Y-PSZ showed no significant influence of aging on strength, hydrothermal reactor aging significantly decreased the in-house Y-PSZ characteristic strength (474 Mpa). Both 5Y-PSZs demonstrated high reliability up to 300-Mpa strength missions, with no detrimental effect of aging (88-100%). SIGNIFICANCE Irrespective of the processing method, ultra-translucent 5Y-PSZ showed high aging resistance and translucency stability, as well as strength corresponding to the indication up to short-span anterior prostheses.
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Affiliation(s)
- Everardo N S de Araújo-Júnior
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil.
| | - Edmara T P Bergamo
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Tiago M C Bastos
- Department of Physics, Technological Institute of Aeronautics, São José dos Campos, SP, Brazil
| | - Ernesto B Benalcázar Jalkh
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Adolfo C O Lopes
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Kelli N Monteiro
- Department of Biomaterial and Oral Biology, University of São Paulo, School of Dentistry, São Paulo, SP, Brazil
| | - Paulo F Cesar
- Department of Biomaterial and Oral Biology, University of São Paulo, School of Dentistry, São Paulo, SP, Brazil
| | - Fernanda C Tognolo
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Rafael Migliati
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Ricardo Tanaka
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
| | - Estevam A Bonfante
- Department of Prosthodontics and Periodontology, University of São Paulo, Bauru School of Dentistry, Bauru, SP, Brazil
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Zhang CN, Zhu Y, Zhang YJ, Jiang YH. Clinical esthetic comparison between monolithic high-translucency multilayer zirconia and traditional veneered zirconia for single implant restoration in maxillary esthetic areas: Prosthetic and patient-centered outcomes. J Dent Sci 2022; 17:1151-1159. [PMID: 35784115 PMCID: PMC9236935 DOI: 10.1016/j.jds.2022.01.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/14/2022] [Indexed: 11/19/2022] Open
Abstract
Background/purpose Clinical esthetic evidence for the performance of monolithic high-translucency multilayer zirconia is lacking. The aim of this study was to compare monolithic high-translucency multilayer zirconia with traditional veneered zirconia in clinical situation. Material and methods A total of 30 participants who were provided with both monolithic zirconia crowns (Group 1) and traditional veneered crowns (Group 2) for single implant restoration in maxillary esthetic areas were enrolled. Patients' subjective outcome (Visual Analog Scale, VAS) were recorded. Photos were taken and then evaluated by 9 evaluators with Pink and White Esthetic Score (WES). Wilcoxon signed rank test was used for comparison between Group 1 and Group 2 in VAS, WES and five variables in WES. Kendall's coefficient of concordance test was used to calculate inter-rater reliability of WES variables. Spearman correlation was used to analyze association between patients' outcome and evaluators' scores. Results There was no significant difference in patients' subjective outcome between monolithic zirconia and traditional veneered crowns: overall VAS were 9.0 (8.0–9.0) and 9.0 (8.5–9.5), respectively (P > 0.05). However, in professional view, significant difference between Group 1 and Group 2 in WES was observed: 7.5 (6.0–8.0) and 8.0 (6.5–8.5), respectively (P < 0.05). Kendall's test showed, among WES variables, translucency demonstrated the highest agreement. Professionally reported evaluations did not correlate with patient-reported outcomes (Spearman correlation were 0.246 and 0.224 for Group 1 and Group 2, respectively). Conclusion Within the limitation of this study, it can be concluded that monolithic high-translucency multilayer zirconia restoration might be a treatment modality.
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Affiliation(s)
- Chu-Nan Zhang
- Department of Implant Dentistry, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Yu Zhu
- Department of Implant Dentistry, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Yi-Jie Zhang
- Department of Implant Dentistry, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China
| | - Yin-Hua Jiang
- Department of Oral and Maxillofacial Implantology, Lishui People’s Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, Lishui, China
- Corresponding author. Department of Oral and Maxillofacial Implantology, Lishui People's Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, No. 15 Dazhong Road, Lishui, 323000, China. Fax: +86 0578 2187120.
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Donker VJJ, Raghoebar GM, Jensen‐Louwerse C, Vissink A, Meijer HJA. Monolithic zirconia single tooth implant‐supported restorations with
CAD
/
CAM
titanium abutments in the posterior region: A 1‐year prospective case series study. Clin Implant Dent Relat Res 2022; 24:125-132. [PMID: 35075756 PMCID: PMC9303442 DOI: 10.1111/cid.13069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/26/2021] [Indexed: 11/29/2022]
Abstract
Purpose To assess the clinical, radiographic, and patient‐reported outcome measures, including the success of screw‐retained monolithic zirconia implant‐supported restorations with CAD/CAM titanium abutments in the posterior region during a 1‐year follow‐up. Methods In a prospective case series, 50 molar sites in the posterior region of 46 patients with a minimum age of 18 years and sufficient bone volume and anatomical conditions for placing an implant (≥8 mm) and an anatomical restoration were included. Parallel‐walled implants with a conical connection were inserted in a two‐stage surgical procedure. Implant uncovering and healing abutment placement occurred 12 weeks after insertion. Two weeks after mucosa healing, a screw‐retained monolithic zirconia restoration with a CAD/CAM titanium abutment was placed. Clinical, radiographic, and patient‐reported outcome measures were collected at baseline before implant placement and then during the 1 month and 1 year follow‐ups. Results At the 1 year follow‐up, 49 restorations could be evaluated. The plaque accumulation, presence of calculus, bleeding tendency and peri‐implant inflammation indices were low, representing healthy peri‐implant conditions. The mean marginal bone level change between the 1 month and the 1 year follow‐up was −0.17 ± 0.46 mm. The mean patient satisfaction was high. The restoration success was, according to the modified USPHS criteria, 95.9%. Conclusion Monolithic zirconia implant‐supported restorations with CAD/CAM titanium abutments have very good clinical, radiographic and patient‐reported outcomes after 1 year in function.
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Affiliation(s)
- Vincent J. J. Donker
- Department of Oral and Maxillofacial Surgery University of Groningen, University Medical Center Groningen Groningen The Netherlands
| | - Gerry M. Raghoebar
- Department of Oral and Maxillofacial Surgery University of Groningen, University Medical Center Groningen Groningen The Netherlands
| | - Charlotte Jensen‐Louwerse
- Department of Implant Dentistry University of Groningen, University Medical Center Groningen Groningen The Netherlands
| | - Arjan Vissink
- Department of Oral and Maxillofacial Surgery University of Groningen, University Medical Center Groningen Groningen The Netherlands
| | - Henny J. A. Meijer
- Department of Oral and Maxillofacial Surgery University of Groningen, University Medical Center Groningen Groningen The Netherlands
- Department of Implant Dentistry University of Groningen, University Medical Center Groningen Groningen The Netherlands
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Alammar A, Blatz MB. The resin bond to high‐translucent zirconia—A systematic review. J ESTHET RESTOR DENT 2022; 34:117-135. [DOI: 10.1111/jerd.12876] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/20/2021] [Accepted: 12/31/2021] [Indexed: 02/01/2023]
Affiliation(s)
- Amirah Alammar
- Sijam Medical Center, Private Practice Riyadh Saudi Arabia
| | - Markus B. Blatz
- School of Dental Medicine, Department of Preventive and Restorative Sciences University of Pennsylvania Philadelphia Pennsylvania USA
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Pjetursson BE, Sailer I, Latyshev A, Rabel K, Kohal RJ, Karasan D. A systematic review and meta-analysis evaluating the survival, the failure, and the complication rates of veneered and monolithic all-ceramic implant-supported single crowns. Clin Oral Implants Res 2021; 32 Suppl 21:254-288. [PMID: 34642991 PMCID: PMC9293296 DOI: 10.1111/clr.13863] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/04/2021] [Indexed: 12/28/2022]
Abstract
Objective To assess the survival, failure, and complication rates of veneered and monolithic all‐ceramic implant‐supported single crowns (SCs). Methods Literature search was conducted in Medline (PubMed), Embase, and Cochrane Central Register of Controlled Trials until September 2020 for randomized, prospective, and retrospective clinical trials with follow‐up time of at least 1 year, evaluating the outcome of veneered and/or monolithic all‐ceramic SCs supported by titanium dental implants. Survival and complication rates were analyzed using robust Poisson's regression models. Results Forty‐nine RCTs and prospective studies reporting on 57 material cohorts were included. Meta‐analysis of the included studies indicated an estimated 3‐year survival rate of veneered‐reinforced glass‐ceramic implant‐supported SCs of 97.6% (95% CI: 87.0%–99.6%). The estimated 3‐year survival rates were 97.0% (95% CI: 94.0%–98.5%) for monolithic‐reinforced glass‐ceramic implant SCs, 96.9% (95% CI: 93.4%–98.6%) for veneered densely sintered alumina SCs, 96.3% (95% CI: 93.9%–97.7%) for veneered zirconia SCs, 96.1% (95% CI: 93.4%–97.8%) for monolithic zirconia SCs and only 36.3% (95% CI: 0.04%–87.7%) for resin‐matrix‐ceramic (RMC) SCs. With the exception of RMC SCs (p < 0.0001), the differences in survival rates between the materials did not reach statistical significance. Veneered SCs showed significantly (p = 0.017) higher annual ceramic chipping rates (1.65%) compared with monolithic SCs (0.39%). The location of the SCs, anterior vs. posterior, did not influence survival and chipping rates. Conclusions With the exception of RMC SCs, veneered and monolithic implant‐supported ceramic SCs showed favorable short‐term survival and complication rates. Significantly higher rates for ceramic chipping, however, were reported for veneered compared with monolithic ceramic SCs.
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Affiliation(s)
- Bjarni Elvar Pjetursson
- Department of Reconstructive Dentistry, Faculty of Odontology, University of Iceland, Reykjavik, Iceland.,Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Irena Sailer
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Andrey Latyshev
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland.,Department of Maxillofacial, Oral and Plastic Surgery, Faculty of Dentistry, Moscow State University of Medicine and Dentistry, Moscow, Russia
| | - Kerstin Rabel
- Department of Prosthetic Dentistry, Faculty of Medicine, Center for Dental Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Ralf-Joachim Kohal
- Department of Prosthetic Dentistry, Faculty of Medicine, Center for Dental Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Duygu Karasan
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
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Mühlemann S, Hjerppe J, Hämmerle CHF, Thoma DS. Production time, effectiveness and costs of additive and subtractive computer-aided manufacturing (CAM) of implant prostheses: A systematic review. Clin Oral Implants Res 2021; 32 Suppl 21:289-302. [PMID: 34642980 PMCID: PMC9293467 DOI: 10.1111/clr.13801] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 04/16/2021] [Accepted: 06/10/2021] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To systematically review the dental literature for clinical studies reporting on production time, effectiveness and/or costs of additive and subtractive computer-aided manufacturing (CAM) of implant prostheses. MATERIALS AND METHODS A systematic electronic search for clinical studies from 1990 until June 2020 was performed using the online databases Medline, Embase and Cochrane. Time required for the computer-aided design (CAD) process, the CAM process, and the delivery of the CAD-CAM prostheses were extracted. In addition, articles reporting on the effectiveness and the costs of both manufacturing technologies were included. RESULTS Nine clinical studies were included reporting on subtractive CAM (s-CAM; 8 studies) and additive CAM (a-CAM; 1 study). Eight studies reported on the s-CAM of prosthetic and auxiliary components for single implant crowns. One study applied a-CAM for the fabrication of an implant bar prototype. Time was provided for the CAD process of implant models (range 4.9-11.8 min), abutments (range 19.7-32.7 min) and crowns (range 11.1-37.6 min). The time for s-CAM of single implant crown components (abutment/crown) ranged between 8.2 and 25 min. Post-processing (e.g. sintering) was a time-consuming process (up to 530 min). At delivery, monolithic/veneered CAD-CAM implant crowns resulted in additional adjustments chairside (51%/93%) or labside (11%/19%). CONCLUSIONS No scientific evidence exists on production time, effectiveness and costs of digital workflows comparing s-CAM and a-CAM. For both technologies, post-processing may substantially contribute to the production time. Considering effectiveness, monolithic CAD-CAM implant crowns may be preferred compared to veneered CAD-CAM crowns.
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Affiliation(s)
- Sven Mühlemann
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Jenni Hjerppe
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Christoph H F Hämmerle
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
| | - Daniel S Thoma
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland
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Lerner H, Nagy K, Pranno N, Zarone F, Admakin O, Mangano F. Trueness and precision of 3D-printed versus milled monolithic zirconia crowns: An in vitro study. J Dent 2021; 113:103792. [PMID: 34481929 DOI: 10.1016/j.jdent.2021.103792] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 11/28/2022] Open
Abstract
PURPOSE To compare the trueness and precision of 3D-printed versus milled monolithic zirconia crowns (MZCs). METHODS A model of a maxilla with a prepared premolar was scanned with an industrial scanner (ATOSQ®, Gom) and an MZC was designed in computer-assisted-design (CAD) software (DentalCad®, Exocad). From that standard tessellation language (STL) file, 10 MZCs (test) were 3D-printed with a Lithography-based Ceramic Manufacturing (LCM) printer (CerafabS65®, Lithoz) and 10 MZCs (control) were milled using a 5-axis machine (DWX-52D®, DGShape). All MZCs were sintered and scanned with the aforementioned scanner. The surface data of each sample (overall crown, marginal area, occlusal surface) were superimposed to the original CAD file (ControlX®, Geomagic) to evaluate trueness: (90-10)/2, absolute average (ABS AVG) and root mean square (RMS) values were obtained for test and control groups (MathLab®, Mathworks) and used for analysis. Finally, the clinical precision (marginal adaptation, interproximal contacts) of test and control MZCs was investigated on a split-cast model printed (Solflex350®, Voco) from the CAD project, and compared. RESULTS The milled MZCs had a significantly higher trueness than the 3D-printed ones, overall [(90-10)/2 printed 37.8 µm vs milled 21.2 µm; ABS AVG printed 27.2 µm vs milled 15.1 µm; RMS printed 33.2 µm vs milled 20.5 µm; p = 0.000005], at the margins [(90-10)/2 printed 25.6 µm vs milled 12.4 µm; ABS AVG printed 17.8 µm vs milled 9.4 µm; RMS printed 22.8 µm vs milled 15.6 µm; p= 0.000011] and at the occlusal level [(90-10)/2 printed 50.4 µm vs milled 21.9 µm; ABS AVG printed 29.6 µm vs milled 14.7 µm; RMS printed 38.9 µm vs milled 22.5 µm; p = 0.000005]. However, with regard to precision, both test and control groups scored highly, with no significant difference either in the quality of interproximal contact points (p = 0.355) or marginal closure (p = 0.355). CONCLUSIONS Milled MZCs had a statistically higher trueness than 3D-printed ones; all crowns, however, showed high precision, compatible with the clinical use. CLINICAL SIGNIFICANCE Although milled MZCs remain more accurate than 3D-printed ones, the LCM technique seems able to guarantee the production of clinically precise zirconia crowns.
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Affiliation(s)
- Henriette Lerner
- Department of Oral Surgery, University of Szeged, Szeged, Hungary.
| | - Katalin Nagy
- Department of Oral Surgery, University of Szeged, Szeged, Hungary.
| | - Nicola Pranno
- Department of Oral and Maxillofacial Sciences, Sapienza University, Rome, Italy.
| | - Fernando Zarone
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, University Federico II, Naples, Italy.
| | - Oleg Admakin
- Department of Pediatric, Preventive Dentistry and Orthodontics, Sechenov First State Medical University, Moscow, Russia.
| | - Francesco Mangano
- Department of Pediatric, Preventive Dentistry and Orthodontics, Sechenov First State Medical University, Moscow, Russia.
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Matsushima K, Kubochi K, Komine F, Kimura F, Kobayashi T, Matsumura H. Bond strength between a veneering composite resin and zirconia frameworks with attached mechanical retentive devices. Dent Mater J 2021; 41:117-125. [PMID: 34483203 DOI: 10.4012/dmj.2021-141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effects of mechanical retentive devices and various surface treatments on the shear bond strength between a veneering composite resin and zirconia was investigated. Zirconia disks were classified into three surface-treatment groups: airborne-particle abrasion, overglazing, and overglazing with white alumina particles of three different grain sizes (50, 70, and 105 μm) attached onto zirconia disks (ZR-50, ZR-70, and ZR-105, respectively). They were further divided into four groups (n=44): unprimed, Clearfil Porcelain Bond Activator (CA), Clearfil Photo Bond (CB), and CA+CB. An indirect composite resin was bonded to zirconia specimens. Shear bond strengths were measured. For the ZR-70 and ZR-105 groups, the CB and CA+CB specimens exhibited higher bond strengths than the other two specimens after thermocycling. The ZR-70 and ZR-105 groups achieved micromechanical interlocking, and priming with a phosphate monomer (MDP) yielded stable bond strengths between the composite resin and zirconia with alumina particles attached as retentive devices.
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Affiliation(s)
- Keisuke Matsushima
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Kei Kubochi
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Futoshi Komine
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Fumiaki Kimura
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Tatsuro Kobayashi
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
| | - Hideo Matsumura
- Department of Fixed Prosthodontics, Nihon University School of Dentistry
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El-Ma'aita A, A Al-Rabab'ah M, Abu-Awwad M, Hattar S, Devlin H. Endocrowns Clinical Performance and Patient Satisfaction: A Randomized Clinical Trial of Three Monolithic Ceramic Restorations. J Prosthodont 2021; 31:30-37. [PMID: 34378269 DOI: 10.1111/jopr.13414] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2021] [Indexed: 01/16/2023] Open
Abstract
PURPOSE The purpose of this randomized, double-blind, clinical trial was to assess the survival of endocrowns made from three different monolithic ceramic materials, and to evaluate patient satisfaction. MATERIALS AND METHODS Fifty-three patients (sixty root canal treated molar teeth) were enrolled. Teeth were prepared to a flat butt-joint margin and randomly divided between three material groups: lithium disilicate-reinforced glass-ceramic, monolithic zirconia and polymer infiltrated hybrid ceramic. Predefined cementation protocols were used. Clinical assessment using modified United States Public Health Service (USPHS) criteria was carried out after two years by two independent clinicians blinded to the material used. Radiographic examination was conducted to check for the presence of caries, excess cement, and periapical infection. Statistical analysis was performed using the Kruskal Wallis and Wilcoxon signed-rank tests as well as the Kaplan-Meier survival estimate. RESULTS Forty-eight patients were available for assessment after 2 years (recall rate 90.6%). The overall Kaplan-Meier survival estimate among all groups was 90.9% with no statistically significant difference between the groups (p = 0.17). Three zirconia endocrowns debonded after 9, 10 and 13 months (82.4% survival rate), while 2 hybrid ceramic endocrowns chipped/fractured (89.5% survival rate). Lithium disilicate endocrowns had a 100% survival rate. The Kruskal Wallis test revealed no statistically significant difference between the groups in the USPHS criteria ratings and the radiographic assessment (P>0.05). Patient satisfaction ranged from 82.3% in the zirconia group to 100% in both the lithium disilicate and hybrid ceramic groups. CONCLUSIONS Endocrowns provide a predictable option for the restoration of endodontically treated molar teeth in the short term. Lithium disilicate-reinforced ceramic had fewer complications and required less intervention compared with zirconia and hybrid ceramics. Long-term follow-up is required to substantiate these study results.
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Affiliation(s)
| | | | | | - Susan Hattar
- School of Dentistry, University of Jordan, Amman, Jordan
| | - Hugh Devlin
- Division of Dentistry, The University of Manchester, Manchester, UK
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Sehovic E, Ioannidis A, Hämmerle CH, Özcan M, Mühlemann S. Effect of tooth brush abrasion on the color, gloss and surface roughness of internally and externally stained monolithic ceramic materials. J Prosthodont Res 2021; 66:303-311. [PMID: 34193746 DOI: 10.2186/jpr.jpr_d_20_00276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
PURPOSE To measure the durability of the color, change in surface roughness and gloss of stained monolithic ceramic materials subjected to artificial tooth brush abrasion. MATERIALS AND METHODS Standardized specimens were manufactured from pressable lithium-disilicate glass ceramic (PC; IPS e.max Press), machinable lithium-disilicate glass ceramic (MC; IPS e.max CAD), and zirconia (ZR; Zenostar). Ceramic staining was applied before (internal; in) and after crystallization/sintering (external; ex). Of each ceramic material, specimens without staining were prepared (no staining; no). Porcelain-fused-to-metal specimens served as control (PFM). Each group consisted of 15 specimens. Tooth brushing was simulated with tooth brushing strokes of 21.6 k, 43.2 k, and 64.8 k. Color, gloss and roughness were measured at baseline and after cycle intervals. Kruskal-Wallis and paired Post-hoc Conover tests were applied to detect statistical differences between treatment groups. Differences before and after aging were calculated by Wilcoxon signed rank test (α=0.05). RESULTS In all groups, color difference (∆E) was statistically significant after aging: no-PC (P<.001, 95% CI[0.14,0.84]), no-MC (P=.003, 95% CI[0.23,1.12]), no-ZR (P=.003, 95% CI [0.33,0.62]), in-MC (P=.003, 95% CI[0.35,0.73]), in-ZR (P=.003, 95% CI[0.09,0.32]), ex-PC (P=.003, 95% CI[0.54,0.98]), ex-MC (P<.001, 95% CI[0.23,1.26]), ex-ZR (P=.003, 95% CI[0.27,0.55]), and PFM (P=.002, 95% CI[0.22,0.34]). Aging increased surface roughness and decreased the gloss within all subgroups showing statistical significance. CONCLUSIONS Color, gloss and roughness of stained monolithic ceramic materials changed significantly by means of tooth brush abrasion in vitro. Color changes were below the threshold value for the detection by the human eye (∆E 1.8).
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Affiliation(s)
- Edis Sehovic
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich
| | - Alexis Ioannidis
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich
| | | | - Mutlu Özcan
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich
| | - Sven Mühlemann
- Clinic of Reconstructive Dentistry, Center of Dental Medicine, University of Zurich
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A straightforward technique for removing titanium bases from screw-retained monolithic implant-supported prostheses. J Prosthet Dent 2021; 128:837-838. [PMID: 34103149 DOI: 10.1016/j.prosdent.2021.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/06/2021] [Accepted: 05/07/2021] [Indexed: 11/23/2022]
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Effect of Ni-Cr Alloy Surface Abrasive Blasting on Its Wettability by Liquid Ceramics. MATERIALS 2021; 14:ma14082007. [PMID: 33923646 PMCID: PMC8073811 DOI: 10.3390/ma14082007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/14/2021] [Accepted: 04/15/2021] [Indexed: 11/17/2022]
Abstract
An adequate surface is essential in ensuring a solid bond between the metal and dental ceramics for metal framework wettability. This work is aimed at investigating the effect of variable abrasive blasting parameters on Ni-Cr alloy surface’s ability to be wetted with liquid ceramics at elevated temperatures. One-hundred and sixty-eight samples were divided into 12 groups (n = 14), which were sandblasted using variable parameters: type of abrasive (Al2O3 and SiC), the grain size of the abrasive (50, 110, and 250 µm), and processing pressure (400 and 600 kPa). After treatment, the samples were cleaned in an ultrasonic cleaner and dried under compressed air. Dental ceramics were applied to the prepared surfaces via drops, and the wettability was tested in a vacuum oven at temperatures in the range of 850–1000 °C. The results were statistically analyzed using ANOVA (α = 0.05). For all surfaces, the contact angles were less than 90° at temperatures below 875 °C. For Al2O3, the best wettability was observed for the smallest particles and, for SiC, the largest particles. The ability to wet the surface of a Ni-Cr alloy is related to its sandblasting properties, such as roughness or the percentage of embedded abrasive particles. It should not be the only factor determining the selection of abrasive blasting parameters when creating a prosthetic restoration.
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