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Yu F, Xiang F, Zhao J, Lin N, Sun Z, Zheng Y. Clinical outcomes of self-glazed zirconia veneers produced by 3D gel deposition: a retrospective study. BMC Oral Health 2024; 24:457. [PMID: 38622649 PMCID: PMC11020188 DOI: 10.1186/s12903-024-04253-2] [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: 01/17/2024] [Accepted: 04/11/2024] [Indexed: 04/17/2024] Open
Abstract
BACKGROUND Self-glazed zirconia (SZ) restorations are made by a novel additive three-dimensional gel deposition approach, which are suitable for a straightforward completely digital workflow. SZ has recently been used as minimally invasive veneer, but its clinical outcomes have not been clarified yet. This study aimed to evaluate the preliminary clinical outcomes of SZ veneers compared with the widely used lithium disilicate glass-ceramic veneers made by either pressing (PG) or milling (MG) process. METHODS Fifty-six patients treated with SZ, PG, and MG veneers by 2 specialists between June 2018 and October 2022 were identified. Patients were recalled for follow-up at least 1 year after restoration. Clinical outcomes were assessed by 2 independent evaluators according to the modified United States Public Health Service (USPHS) criteria. Overall patient satisfaction was assessed using visual analogue scale (VAS), and analyzed by one-way ANOVA. Chi-square test was applied to compare the difference in the success and survival rates among the 3 groups. RESULTS A total of 51 patients restored with 45 SZ, 40 PG, and 41 MG veneers completed the study, with a patient dropout rate of 8.9%. Mean and standard deviation of follow-up period was 35.0 ± 14.7 months. All restorations performed well at baseline, except for 2 SZ veneers with mismatched color (rated Bravo). During follow-up, marginal discrepancy (rated Bravo) was found in 4 MG veneers and 1 PG veneer, and partially fractured (rated Charlie) was found in another 2 PG veneers. The survival rate of SZ, PG, and MG veneers was 100%, 95%, and 100%, with a success rate of 95.56%, 92.50%, and 90.24%, respectively, none of which were significantly different (p = 0.099 and 0.628, respectively). The mean VAS score of SZ, PG, and MG was 95.00 ± 1.57, 93.93 ± 2.40, and 94.89 ± 2.00 respectively, without significant difference (p > 0.05). CONCLUSION SZ veneers exhibited comparable preliminary clinical outcomes to PG and MG veneers, which could be considered as a feasible option for minimally invasive restorative treatment.
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Affiliation(s)
- Feifei Yu
- School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
- 903 Hospital People's Liberation Army, Hangzhou, Zhejiang, China
| | - Fangyue Xiang
- School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Jing Zhao
- School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Nengjie Lin
- School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Zhe Sun
- School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China
| | - Yuanna Zheng
- School/Hospital of Stomatology, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, China.
- Ningbo Dental Hospital/Ningbo Oral Health Research Institute, Ningbo, Zhejiang, China.
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Abdelhady WA, Metwally MF, Haggag KM. Effect of thermomechanical loading on fracture resistance and failure mode of new pressable zirconia-reinforced lithium disilicate onlay restoration. J Dent Res Dent Clin Dent Prospects 2024; 18:29-36. [PMID: 38881646 PMCID: PMC11179138 DOI: 10.34172/joddd.40843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 01/29/2024] [Indexed: 06/18/2024] Open
Abstract
Background Insufficient information exists regarding the fracture resistance and failure pattern of newly developed zirconia-reinforced lithium disilicate (ZL, Vita Ambria) onlays. This in vitro study compared the fracture resistance of two types of onlays: monolithic lithium disilicate (LD) and monolithic ZL. Methods Forty-eight ceramic onlay restorations were fabricated on epoxy dies using a maxillary first premolar model. The samples were divided into two main groups: LD and ZL. Half of each group was subjected to thermomechanical fatigue loading (TML) using a chewing simulator. All the samples were cemented with self-adhesive resin cement. Subsequently, they were loaded until failure in a universal testing machine, and the fracture patterns and resistance were recorded. Results Before TML, ZL demonstrated the highest statistically significant mean fracture resistance (499.76±34.14N) compared to LD (470.40±27.38N). After TML, ZL showed the highest non-statistically significant mean fracture resistance (429.27±131.42N), while LD's mean fracture resistance decreased (377.31±62.18N). Conclusion Monolithic zirconia-reinforced onlays demonstrated higher fracture resistance and a more favorable failure mode compared to LD. However, the impact of thermomechanical aging resulted in reduced fracture resistance for both materials, with a notable preference observed for ZL.
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Affiliation(s)
- Walid A Abdelhady
- Crown and Bridge Department, Faculty of Dental Medicine, Al Azhar University, Cairo, Egypt
| | - Mohamed F Metwally
- Crown and Bridge Department, Faculty of Dental Medicine, Al Azhar University, Cairo, Egypt
| | - Khaled M Haggag
- Crown and Bridge Department, Faculty of Dental Medicine, Al Azhar University, Cairo, Egypt
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Li R, Li W, Wang Y, Sun Y. Knife-edged crown fabricated by 3-dimensional gel deposition and soft milling. J Prosthet Dent 2023; 129:174-180. [PMID: 34052028 DOI: 10.1016/j.prosdent.2021.04.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 04/06/2021] [Accepted: 04/06/2021] [Indexed: 01/18/2023]
Abstract
STATEMENT OF PROBLEM Restorations with knife-edge margins are more prone to margin chipping during the manufacturing process. Three-dimensional gel deposition shows potential for fabricating zirconia restorations with good margin quality, but studies on its performance in fabricating knife-edged crowns are lacking. PURPOSE The purpose of this in vitro study was to compare the 3-dimensional trueness, surface morphology, and margin quality of self-glazed zirconia and soft-milled zirconia crowns with knife-edge margins. MATERIAL AND METHODS An abutment with a knife-edge finish line design was prepared and scanned with a laboratory scanner. Anatomic contour crowns were designed and fabricated by 3-dimensional gel deposition and soft milling (n=5). The crowns were digitalized, and the scan data were superimposed on the computer-aided design (CAD) data for 3-dimensional deviation analysis. Surface morphology and margin quality were characterized with microscopic examination. RESULTS The self-glazed zirconia crowns showed a smooth and glossy appearance. The soft-milled crowns showed traces left by the removal of support bars and numerous micropits of various sizes. In internal areas, no significant difference was found in root mean square values between the 2 groups (P>.05). For the external surface, self-glazed zirconia showed statistically lower root mean square values than the soft-milled crowns (P<.05). When observed at ×5 magnification, all the self-glazed zirconia crowns showed smooth edges with no defects, whereas small or large margin defects were found in the soft-milled crowns. When characterized at ×200 magnification, minor margin flaws were observed in the self-glazed zirconia crowns. More and larger margin defects were found in the soft-milled crowns. CONCLUSIONS Three-dimensional gel deposition forms a smoother and more homogeneous surface than soft milling. Knife-edged self-glazed zirconia crowns have good dimensional accuracy and margin quality.
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Affiliation(s)
- Rong Li
- Doctoral student, Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology, National Clinical Research Center for Oral Disease, Beijing, PR China
| | - Weiwei Li
- Postdoctor, Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology & National Clinical Research Center for Oral Disease, Beijing, PR China
| | - Yong Wang
- Professor, Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology & National Clinical Research Center for Oral Disease, Beijing, PR China
| | - Yuchun Sun
- Professor, Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology & National Clinical Research Center for Oral Disease, Beijing, PR China.
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Mancuso E, Mazzitelli C, Maravic T, Pitta J, Mengozzi A, Comba A, Baldi A, Scotti N, Mazzoni A, Fehmer V, Sailer I, Breschi L. The influence of finishing lines and margin location on enamel and dentin removal for indirect partial restorations: A micro-CT quantitative evaluation. J Dent 2022; 127:104334. [PMID: 36257512 DOI: 10.1016/j.jdent.2022.104334] [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: 04/29/2022] [Revised: 10/11/2022] [Accepted: 10/14/2022] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVES This in vitro research aimed to quantitatively evaluate the enamel and dentin tissue removal and the residual adhesion surface area (RAS) after different margin designs and locations for indirect partial restorations (IPR). METHODS A human molar was scanned using a Micro-CT and the STL file obtained was used to 3D-print 50 resin-tooth replicas. IPR standardized preparations were performed. The specimens were randomly assigned to 5 groups (n = 10), according to preparation and margin location to the dental equator (DE): 1) Rounded shoulder above the DE (SA); 2) Hollow chamfer above the DE (CA); 3) Butt joint above the DE (BJ); 4) Rounded shoulder below the DE (SB); 5) Chamfer below the DE (CB). Then, the tooth replicas were scanned and each STL file was aligned and superimposed to the original STL model file. Data of enamel and dentin volume removal and RAS were assessed and statistically analyzed (one-way ANOVA and Kruskal-Wallis tests for the two dental substrates respectively). Significance was set at p<0.05. RESULTS Differences in dental tissue reductions were related to the margin location. Above the equator, SA, CA, and BJ performed comparably (p>0.05). Below the equator, CB was significantly more conservative in enamel reduction than SB (p<0.05) and showed the highest enamel adhesive surface exposure among the tested preparations (p<0.05). CONCLUSIONS When the preparation margin is placed above DE, BJ determines a greater exposure of dentin, reducing the adhesive surface in enamel. Below DE, SB seems to be more aggressive in terms of tissue removal compared to CB. CLINICAL SIGNIFICANCE The results of this in vitro study suggest that in teeth requiring partial restoration with the margin below the dental equator, a chamfer preparation would be more conservative than a shoulder preparation. When above the equator, preparations with flat designs would expose more dentine providing a worse substrate for adhesion.
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Affiliation(s)
- Edoardo Mancuso
- Department of Biomedical and Neuromotor Science (DIBINEM), Alma Mater University of Bologna, via S. Vitale 59, 40125 Bologna, Italy
| | - Claudia Mazzitelli
- Department of Biomedical and Neuromotor Science (DIBINEM), Alma Mater University of Bologna, via S. Vitale 59, 40125 Bologna, Italy
| | - Tatjana Maravic
- Department of Biomedical and Neuromotor Science (DIBINEM), Alma Mater University of Bologna, via S. Vitale 59, 40125 Bologna, Italy
| | - João Pitta
- Division of Fixed Prosthodontics and Biomaterials, University Clinics for Dental Medicine, University of Geneva, Geneva, Switzerland
| | - Alessandro Mengozzi
- Department of Biomedical and Neuromotor Science (DIBINEM), Alma Mater University of Bologna, via S. Vitale 59, 40125 Bologna, Italy
| | - Allegra Comba
- Department of Surgical Sciences, Dental School Lingotto, University of Turin, Via Nizza 230, 10126 Turin, Italy
| | - Andrea Baldi
- Department of Surgical Sciences, Dental School Lingotto, University of Turin, Via Nizza 230, 10126 Turin, Italy
| | - Nicola Scotti
- Department of Surgical Sciences, Dental School Lingotto, University of Turin, Via Nizza 230, 10126 Turin, Italy
| | - Annalisa Mazzoni
- Department of Biomedical and Neuromotor Science (DIBINEM), Alma Mater University of Bologna, via S. Vitale 59, 40125 Bologna, Italy
| | - Vincent Fehmer
- 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
| | - Lorenzo Breschi
- Department of Biomedical and Neuromotor Science (DIBINEM), Alma Mater University of Bologna, via S. Vitale 59, 40125 Bologna, Italy.
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3-D Surface Morphological Characterization of CAD/CAM Milled Dental Zirconia: An In Vitro Study of the Effect of Post-Fabrication Processes. MATERIALS 2022; 15:ma15134685. [PMID: 35806812 PMCID: PMC9268120 DOI: 10.3390/ma15134685] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/06/2022] [Accepted: 06/18/2022] [Indexed: 02/04/2023]
Abstract
Objective: To investigate the effect on zirconia surface of the post-fabrication surface treatments on the morphological characteristics and mechanical properties of CAD/CAM milled dental zirconia specimens as well as to identify the critical parameters in the measurement of oral retention under in vitro circumstances. Method: The zirconia specimens (N = 20, n = 4) were subjected to CAD/CAM milling and divided into five groups. The specifications were: Group G1—sintered; Group G2—sintered followed by a polishing process; Group G3—sintered followed by polishing and sandblasting with alumina particles Al2O3 (110 µm); Group G4—sintered followed by sandblasting; Group G5—sintered followed by sandblasting with polishing as the end process. All the groups were subjected to Fretting wear tests, 3-D surface roughness measurements, and Vickers’s Micro hardness tests. Investigation of the phase transformation using XRD, and surface feature examination using SEM were also carried out. Additionally, one-way ANOVA, Tukey, and Pearson correlations were statistically analysed. Results: The fabrication processes had a significant effect on the performance of zirconia specimens in all the groups (p > 0.05). Specimens that underwent polishing as the last process exhibited lower surface roughness. The monoclinic phase of zirconia was observed in all the specimens before and after wear except for those in the G2 and G5 groups, where polishing was the end process. In G5, the post-wear surface properties revealed lower surface roughness and hardness. Further, the SEM and 3-D topography show grooves as seen by the dale void volume (Vvv) values; shallow valley depth (Svk); micro craters; and wear track. Conclusion: Specimens in G5 that were subjected to multistep post-fabrication process, namely sandblasting followed by polishing, yielded better results when compared to those in the other groups (G1, G2, G3, and G4). G5 with an interlayer of alumina is recommended for clinical applications due to its enhanced surface properties, mechanical properties, and low wear.
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Drancourt N, Nicolas E, Veyrune JL, Bessadet M. Comprehensive CAD/CAM Prosthetic Rehabilitation Management in a Young Patient with Agenesis: A Case Report. Healthcare (Basel) 2022; 10:healthcare10020382. [PMID: 35206996 PMCID: PMC8871914 DOI: 10.3390/healthcare10020382] [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: 01/25/2022] [Revised: 02/14/2022] [Accepted: 02/15/2022] [Indexed: 02/05/2023] Open
Abstract
With the advancement in ceramic restorations bonded to the tooth structure, the treatment has become a practicable and conservative option to restore teeth with shape alteration owing to the high demand for aesthetics, with minimum tooth preparation. This article describes the case of a 25-year-old man who was dissatisfied with his smile. After an assessment of the clinical situation, a decision was made to place a full-mouth prosthodontic rehabilitation (monolithic lithium disilicate glass-ceramic, IPS E-max CAD) with minimal tooth preparation, which figures as a conservative full-coverage approach. The restoration of an aesthetic smile resulted in the patient’s satisfaction. Bonding of all monolithic veenerlay and crowns onto minimally prepared teeth figures as conservative treatment in cases of hypodontia.
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Affiliation(s)
- Noémie Drancourt
- Centre de Recherche en Odontologie Clinique (CROC), Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (E.N.); (J.-L.V.); (M.B.)
- Service d’Odontologie, CHU Clermont-Ferrand, 63003 Clermont-Ferrand, France
- Correspondence:
| | - Emmanuel Nicolas
- Centre de Recherche en Odontologie Clinique (CROC), Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (E.N.); (J.-L.V.); (M.B.)
- Service d’Odontologie, CHU Clermont-Ferrand, 63003 Clermont-Ferrand, France
| | - Jean-Luc Veyrune
- Centre de Recherche en Odontologie Clinique (CROC), Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (E.N.); (J.-L.V.); (M.B.)
- Service d’Odontologie, CHU Clermont-Ferrand, 63003 Clermont-Ferrand, France
| | - Marion Bessadet
- Centre de Recherche en Odontologie Clinique (CROC), Université Clermont Auvergne, 63000 Clermont-Ferrand, France; (E.N.); (J.-L.V.); (M.B.)
- Service d’Odontologie, CHU Clermont-Ferrand, 63003 Clermont-Ferrand, France
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Yu P, Xiong Y, Zhao P, Yu H, Arola D, Gao S. Ceramic Inlay Bonded Interfaces in Minimally Invasive Preparations: Damage and Contributing Mechanisms in Sliding Contact. Oper Dent 2021; 47:E1-E11. [PMID: 34843621 DOI: 10.2341/20-144-l] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2021] [Indexed: 11/23/2022]
Abstract
BACKGROUND In the preparation of inlay cavities, a choice must be made between conventional standard and minimally invasive preparation designs; in the long run, this choice can affect the integrity of the bonded interface. PURPOSE To evaluate the effect of minimally invasive cavity preparation designs on the extent and contributing mechanisms of damage to ceramic inlay bonded interfaces. METHODS AND MATERIALS Tooth blocks with 90°, 120° and 75° marginal angles were prepared, representing tooth cavities with conventional standard and minimally invasive preparations with large divergence and convergence angles and bonded to monolithic ceramic (IPS e.max CAD). Vickers indentations were placed at various distances from the bonded interface. The indentation morphology and crack length were observed. Reciprocating wear tests were performed on the bonded interface with a 20-newton (N) vertical load. The wear depth and wear-scar morphology were characterized after increments of cyclic sliding contact. RESULTS The 120° group exhibited longer indentation cracks in the ceramic, whereas the 75° group showed larger indentations in the enamel when compared to the 90° group (p<0.001). Consistent with the weaker edge crack resistance, the 120° group experienced the greatest wear (p=0.008), and the wear depth in the enamel of the 75° group exceeded that of the 90° group (p<0.001) in the early stage (5×102 cycles). However, no significant difference in the wear depth (p>0.147) and morphology were found at the later wear stage among the three groups. CONCLUSION Within the limitations of this study, minimally invasive preparations with 120° and 75° marginal angles can result in early sever damage at the ceramic inlay bonded interface but show comparable wear behaviors to the conventional 90° group at the later stage.
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Affiliation(s)
- P Yu
- Ping Yu, PhD, DDS, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Y Xiong
- Yuhuan Xiong, MD, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - P Zhao
- Peng Zhao, MD, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - H Yu
- Haiyang Yu, PhD, DDS, professor, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - D Arola
- Dwayne Arola, PhD, professor, Department of Materials Science and Engineering, Department of Oral Health Sciences, Department of Restorative Dentistry, University of Washington, Seattle, WA, USA
| | - S Gao
- *Shanshan Gao, PhD, DDS, associate professor, State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Baldissara P, Koci B, Monaco C, Scotti N, Breschi L, Ciocca L. Fatigue failure and success rate of lithium disilicate table-tops as a function of cement thickness. J Prosthodont Res 2021; 65:528-534. [PMID: 34108297 DOI: 10.2186/jpr.jpr_d_20_00220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
PURPOSE Under thin, partial coverage restoration the proper cement thickness to be clinically employed still remains an issue. The aim of this study was to determine the failure and success rates of simplified lithium disilicate occlusal veneers as a function of cement thickness. The null hypothesis was that cement thickness has no effect on the fatigue resistance. METHODS Sound human molars were severed in a plane parallel to the occlusal surface to create a flat dentin surface surrounded by enamel edges. Forty-five occlusal veneers 1.0 mm thick (IPS e.max CAD LT) were luted to the teeth with Multilink Automix resin cement, creating 3 experimental groups (n=15) with cement thicknesses of 50, 100, and 200 µm. The restorations were fatigue-cycled using a ball mill machine containing zirconia and stainless steel spheres. Twelve 60 min cycles were performed. Survival statistics were applied to "failure" and "success" events, comparing the three groups using a log-rank Mantel-Cox test and a log-rank test for trends (alpha = 0.05). RESULTS The failure and success rates were not significantly influenced by cement thickness (P = 0.137 and P = 0.872, respectively); thus, the null hypothesis was accepted. However, when log-rank test for trends was applied to failure events, the tendency to have less failures with increasing thicknesses was found statistically significant (P = 0.047). CONCLUSIONS The cement thickness within the range adopted here did not have a significant effect on the failure or success rate of lithium disilicate occlusal veneers when exposed to randomized impact stresses generating fatigue phenomena.
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Affiliation(s)
- Paolo Baldissara
- Section of Prosthodontics, Department of Biomedical and Neuromotor Science, Alma Mater Studiorum University of Bologna
| | - Brunilda Koci
- Faculty of Dental Sciences, Aldent University, Tirana
| | - Carlo Monaco
- Department of Biomedical and Neuromotor Science, Alma Mater Studiorum University of Bologna
| | - Nicola Scotti
- Department of Surgical Sciences, University of Turin
| | - Lorenzo Breschi
- Section of Prosthodontics, Department of Biomedical and Neuromotor Science, Alma Mater Studiorum University of Bologna
| | - Leonardo Ciocca
- Section of Prosthodontics, Department of Biomedical and Neuromotor Science, Alma Mater Studiorum University of Bologna
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Li R, Chen H, Wang Y, Sun Y. Performance of stereolithography and milling in fabricating monolithic zirconia crowns with different finish line designs. J Mech Behav Biomed Mater 2020; 115:104255. [PMID: 33340775 DOI: 10.1016/j.jmbbm.2020.104255] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 10/22/2022]
Abstract
Subtractive manufacturing has become the dominant method in fabricating zirconia dental restorations while additive manufacturing is emerging as a potential alternative. The aim of this in vitro study was to investigate the performance of stereolithography (SLA) and milling in fabricating monolithic zirconia crowns with different finish line designs. Full-contour crowns with three finish lines (chamfer, rounded shoulder, knife-edge) were designed and fabricated by SLA and milling. Fabrication accuracy was accessed by 3D deviation analysis and margin quality was characterized under microscopes. The obtained root mean square value was significantly influenced by finish line design (P < 0.05) but not by fabrication method (P>0.05). However, the color-difference map showed crowns fabricated by SLA and milling had different error distribution in external surfaces. SLA-printed crowns exhibited margins of rounded line angle and without small flaws, although large chippings were found in knife-edged crowns. In milling group, crowns showed margins of sharp line angle and with separate chippings. More and larger margin chippings were found in knife-edged crowns by milling. The results indicate that SLA and milling can fabricate monolithic zirconia crowns of comparable accuracy and knife-edged crowns are prone to large margin chippings by either of the two manufacturing methods.
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Affiliation(s)
- Rong Li
- Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology, National Clinical Research Center for Oral Disease, Beijing, 100081, China
| | - Hu Chen
- Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology, National Clinical Research Center for Oral Disease, Beijing, 100081, China
| | - Yong Wang
- Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology, National Clinical Research Center for Oral Disease, Beijing, 100081, China
| | - Yuchun Sun
- Center of Digital Dentistry, Department of Prosthodontics, Peking University School and Hospital of Stomatology, National Engineering Laboratory for Digital and Material Technology of Stomatology, Research Center of Engineering and Technology for Digital Dentistry of Ministry of Health, Beijing Key Laboratory of Digital Stomatology, National Clinical Research Center for Oral Disease, Beijing, 100081, China.
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