1
|
Oh SE, Park JM, Kim JH, Shim JS, Park YB. Mechanical properties and crown accuracy of additively manufactured zirconia restorations. Dent Mater 2024:S0109-5641(24)00219-7. [PMID: 39060128 DOI: 10.1016/j.dental.2024.07.016] [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: 05/27/2024] [Revised: 07/19/2024] [Accepted: 07/23/2024] [Indexed: 07/28/2024]
Abstract
OBJECTIVES We evaluated the mechanical properties of zirconia restorations produced via additive manufacturing (AM) and the crown accuracy of zirconia crowns. METHODS Zirconia disks, bars, and crowns were manufactured via subtractive (CNC group) and additive manufacturing (AM group) techniques. Disk-shaped specimens in each group were autoclaved at 134 °C and 216 kPa for 5, 10, and 24 h. The phases of the specimens were analyzed using an X-ray diffractometer. The flexural strengths were measured via biaxial flexural tests. The morphologies were examined using a scanning electron microscope. The correlation between the m-phase fraction and biaxial flexural strength by autoclave time in each group was analyzed via linear mixed model and Pearson's correlation analysis. For each group, crown specimens were used to assess the marginal and internal gaps using the replica technique. Buccolingual and mesiodistal cross-sections were measured, and a repeated measures one-way ANOVA was performed. RESULTS Linear mixed model analysis indicated that for both groups, with an increase in the autoclave time, the flexural strength decreased, whereas the m-phase fraction increased. Pearson's correlation analysis revealed no correlation between the m-phase fraction and flexural strength for either group. A repeated measures one-way ANOVA was conducted on instrumented sections (buccal, lingual, mesial, and distal), revealing that the marginal and internal gaps of AM-produced zirconia crowns were less accurate than those of CNC-produced zirconia crowns. SIGNIFICANCE These findings suggest that additively produced zirconia restorations have mechanical properties comparable to those of conventionally produced ceramics and may be suitable for clinical applications.
Collapse
Affiliation(s)
- Sae-Eun Oh
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Ji-Man Park
- Department of Prosthodontics and Dental Research Institute, Seoul National University School of Dentistry, 101 Daehak-ro, Jongno-gu, Seoul 03080, Republic of Korea
| | - Jee-Hwan Kim
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - June-Sung Shim
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea
| | - Young-Bum Park
- Department of Prosthodontics, College of Dentistry, Yonsei University, Seoul 03722, Republic of Korea.
| |
Collapse
|
2
|
Yang J, Li H. Accuracy of CAD-CAM milling versus conventional lost-wax casting for single metal copings: A systematic review and meta-analysis. J Prosthet Dent 2024; 132:51-58. [PMID: 35788274 DOI: 10.1016/j.prosdent.2022.05.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/23/2022] [Accepted: 05/23/2022] [Indexed: 11/29/2022]
Abstract
STATEMENT OF PROBLEM Information comparing the marginal and internal adaptation of single metal copings fabricated via computer-aided design and computer-aided manufacturing (CAD-CAM) milling and lost-wax casting is insufficient. PURPOSE The purpose of this systematic review and meta-analysis was to compare the adaptation of single metal copings fabricated via CAD-CAM milling to that of copings fabricated via lost-wax casting and to identify factors that influenced their accuracy. MATERIAL AND METHODS Following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, Elsevier ScienceDirect, PubMed, Cochrane Library, SpringerLink, and Wiley online databases were searched to select qualified articles, which were assessed by the methodological items for nonrandomized studies (MINORS) criteria. The data on the mean absolute marginal gap, marginal gap, axial gap, occlusal gap, and internal gap values of single metal copings fabricated via CAD-CAM milling and lost-wax casting were extracted, and meta-analysis and meta-regression were used with R software (α=.05) and random-effects models to estimate differences and homogeneity between the 2 methods. RESULTS For the single metal copings, lost-wax casting and CAD-CAM milling led to similar marginal and internal accuracies, but lost-wax casting led to better absolute marginal gap values. For the cast copings, Ni-Cr alloy (92.8 μm) and noble alloy (51.5 μm) led to the largest and smallest marginal gaps, respectively, (P=.005). For milled copings, the noble alloy led to the smallest marginal gap (19.1 μm), and Co-Cr alloy to the largest (76.2 μm) (P=.012). Soft milling led to a more accurate marginal gap (41.4 μm) than hard milling (66.1 μm) (P=.04). CONCLUSIONS When CAD-CAM milling was used to fabricate single metal copings, no advantage in precision was found compared with lost-wax casting, and single metal copings cast from handmade conventional wax patterns had better marginal adaptation than those fabricated via CAD-CAM milling. Noble metal copings had improved marginal accuracy than base metal copings for both the casting and milling methods. Single copings fabricated via soft milling from unsintered metal blocks had more accurate marginal adaption than copings fabricated via hard milling.
Collapse
Affiliation(s)
- Jun Yang
- Lecturer, Department of Restorative Dentistry, Stomatological Hospital of Chongqing Medical University, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, PR China.
| | - Hainan Li
- Professor, School of Management Science and Engineering, Chongqing Technology and Business University, Chongqing, PR China
| |
Collapse
|
3
|
Abulhamael SM, Papathanasiou A, Kostagianni A, Jain S, Finkelman M, Mourão CF, Ali A. Evaluation of marginal and internal adaptation of veneers generated by the guided prosthetic tooth preparation system. J ESTHET RESTOR DENT 2024; 36:911-919. [PMID: 38407478 DOI: 10.1111/jerd.13210] [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: 09/27/2023] [Revised: 01/22/2024] [Accepted: 02/06/2024] [Indexed: 02/27/2024]
Abstract
OBJECTIVE This in vitro study aimed to assess and contrast the marginal and internal adaptation of all-ceramic prefabricated veneers manufactured via the FirstFit guided tooth preparation system against all-ceramic veneers produced using the chairside Computer-Aided Design/Computer Aided Manufacture (CAD/CAM) system following identical guided preparation protocols. MATERIALS AND METHODS Two main groups were included, with 16 lithium disilicate veneers per group. Four typodonts were used for the test (FirstFit) and control CAD/CAM groups. Intraoral scans created master casts and preparation guides. Guides performed preparations on typodont teeth (two central incisors and two lateral incisors). Prepared teeth were scanned (CEREC Omnicam) to design and mill CAD/CAM veneers. Marginal gap thickness and cement space thickness were measured using light microscopy at four locations: marginal, cervical internal, middle internal, and incisal internal. RESULTS No significant difference existed between groups for marginal adaptation (p = 0.058) or incisal internal adaptation (p = 0.076). The control group had significantly lower values for middle internal adaptation (p = 0.023) and cervical internal adaptation (p = 0.019). CONCLUSIONS Guided preparation evaluation showed no significant differences in marginal or incisal internal adaptation. The CAD/CAM group had significantly lower middle and cervical internal adaptation values.
Collapse
Affiliation(s)
- Shahad M Abulhamael
- Department of Prosthodontics, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
| | - Aikaterini Papathanasiou
- Department of Comprehensive Care, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
| | - Aikaterini Kostagianni
- Department of Prosthodontics, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
- Prosthodontist, Private Practice Los Altos, Los Altos, California, USA
| | - Shruti Jain
- Department of Public Health and Community Service, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
| | - Matthew Finkelman
- Department of Public Health and Community Service, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
| | - Carlos Fernando Mourão
- Department of Periodontology, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
| | - Ala Ali
- Department of Prosthodontics, Tufts University School of Dental Medicine, Boston, Massachusetts, USA
- Prosthodontics, Private Practice, Malden, Massachusetts, USA
| |
Collapse
|
4
|
Giti R, Farrahi P. Marginal fit of 3-unit implant-supported fixed partial dentures: Influence of pattern fabrication method and repeated porcelain firings. PLoS One 2024; 19:e0301799. [PMID: 38625846 PMCID: PMC11020902 DOI: 10.1371/journal.pone.0301799] [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: 01/08/2024] [Accepted: 03/23/2024] [Indexed: 04/18/2024] Open
Abstract
BACKGROUND Marginal fit significantly impacts the long-term success of dental restorations. Different pattern fabrication methods, including hand-waxing, milling, or 3D printing, may affect restorations accuracy. The effect of porcelain firing cycles on the marginal fit of metal-ceramic restorations remains controversial, with conflicting findings across studies. PURPOSE The aim was to evaluate the potential effects of multiple porcelain firings (3, 5, 7 cycles) as well as pattern fabrication method (conventional hand-waxing, milling, and 3D printing) on the marginal adaptation of 3-unit implant-supported metal-ceramic fixed partial dentures. It was hypothesized that neither the wax pattern fabrication method nor repeated ceramic firings would significantly affect the marginal adaptation of metal-ceramic crowns. METHODS In this in-vitro study, 30 Cobalt-Chromium alloy frameworks were fabricated based on pattern made through three techniques: conventional hand-waxing, CAD-CAM milling, and CAD-CAM 3D printing (n = 10 per group). Sixteen locations were marked on each abutment to measure the vertical marginal gap at four stages: before porcelain veneering and after 3, 5, and 7 firing cycles. The vertical marginal gap was measured using direct microscopic technique at ×80 magnification. Mean vertical marginal gap values were calculated and two-way ANOVA and Tukey's post hoc tests were used for inter-group comparisons (α = 0.05). RESULTS The 3D printing group showed significantly lower (P<0.001) mean vertical marginal gaps (60-76 μm) compared to the milling (77-115 μm) and conventional hand-waxing (102-110 μm) groups. The milling group exhibited a significant vertical gap increase after 3 firing cycles (P<0.001); while the conventional (P = 0.429) and 3D printing groups (P = 0.501) showed no significant changes after 7 firing cycles. Notably, the vertical marginal gap in all groups remained below the clinically acceptable threshold of 120 μm. CONCLUSION CAD-CAM 3D printing provided superior marginal fit compared to CAD-CAM milling and conventional hand-wax pattern fabrication methods. The impact of porcelain firing on the mean marginal gap was significant only in the milling group. All three fabrication techniques yielded clinically acceptable vertical marginal adaptation after repeated firings. Additive manufacturing holds promise to produce precise implant-supported prostheses.
Collapse
Affiliation(s)
- Rashin Giti
- Oral and Dental Diseases Research Center, Faculty of Dentistry, Shiraz University of Medical Sciences, Shiraz, Fars, Iran
- Department of Prosthodontics, Faculty of Dentistry, Shiraz University of Medical Sciences, Shiraz, Fars, Iran
| | - Pardis Farrahi
- Student Research Committee, Faculty of Dentistry, Shiraz University of Medical Sciences, Shiraz, Fars, Iran
| |
Collapse
|
5
|
Htat HL, Takaichi A, Kajima Y, Kittikundecha N, Kamijo S, Hanawa T, Wakabayashi N. Influence of stress-relieving heat treatments on the efficacy of Co-Cr-Mo-W alloy copings fabricated using selective laser melting. J Prosthodont Res 2024; 68:310-318. [PMID: 37438109 DOI: 10.2186/jpr.jpr_d_22_00283] [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: 07/14/2023]
Abstract
Purpose This study aimed to evaluate the influence of stress-relieving heat treatments on the metal-ceramic bond strength and fitness accuracy of selective laser melting (SLM)-fabricated Co-Cr alloy copings.Methods SLM-manufactured Co-Cr samples were stress-relieved at 750 (Ht-750) and 1150 °C (Ht-1150). The microstructure, surface roughness, metal-ceramic bond strength, marginal and internal fit, Vickers hardness, and residual stress were then compared with those of the non-heat-treated group (As-built). The results were analyzed using one-way ANOVA and post-hoc tests (Tukey's or Student's t test) (P = 0.05).Results The microstructure of the Ht-1150 samples had a brittle oxide layer and lower surface roughness, resulting in significantly lower bond strength values than those of the other groups. The As-built group exhibited significantly lower marginal gap values than the Ht-750 and Ht-1150 groups. Therefore, the post-heat treatments degraded the marginal fitness. The surface residual stress in all sample groups were compressive because of the sandblasting effect. The compressive stresses were larger in Ht-1150 than in As-built and Ht-750 owing to their low hardness values.Conclusions Stress-relief annealing porcelain-fused-to-metal single crowns does not improve bond strength and degrades fitness accuracy because additional post-heat treatments induce thermal distortion. These findings are expected to facilitate the direct application of As-built SLM single crowns in dentistry to minimize post-manufacturing costs and time.
Collapse
Affiliation(s)
- Hein Linn Htat
- Department of Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Atsushi Takaichi
- Department of Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yuka Kajima
- Department of Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Nuttaphon Kittikundecha
- Department of Conservative Dentistry and Prosthodontics, Faculty of Dentistry, Srinakharinwirot University, Bangkok, Thailand
| | - Shingo Kamijo
- Basic Oral Health Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takao Hanawa
- Department of Metallic Biomaterials, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Noriyuki Wakabayashi
- Department of Advanced Prosthodontics, Oral Health Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| |
Collapse
|
6
|
Daou EE, Salameh P. Does the choice of the measuring technique affect the comparison of fit between zirconia and cobalt-chromium prostheses? J Indian Prosthodont Soc 2024; 24:201-207. [PMID: 38650346 PMCID: PMC11129817 DOI: 10.4103/jips.jips_429_23] [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: 08/28/2023] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 04/25/2024] Open
Abstract
AIMS The objectives of the study were to compare the adaptation of presintered zirconia and cobalt- chromium prostheses using microcomputed tomography (μCT), scanning electron microscopy (SEM), and stereomicroscope (SM). MATERIALS AND METHODS Twenty-four fixed dental prostheses (FDPs) were fabricated on metal abutments, duplicated from maxillary first premolar and first molar prepared on a typodont model. Teeth were reduced to obtain chamfer of 1.2 mm and reduction occlusaly of 2 mm occlusal. Scanning of the abutments was done with random assignment to two groups receiving the FDPs made from soft-milled Co-Cr (n = 12) and zirconia (n = 12). Marginal and internal gaps were assessed using three evaluation techniques (X-ray microcomputer tomography, SEM, and stereomicroscopy). STATISTICAL ANALYSIS USED Comparison of the results was made using Levene and analysis of variance tests (α =0.05). RESULTS Irrespective of the material tested, statistical differences were found between the measuring techniques (P = 0.001 overall); the obtained mean gaps were for CT scan (92.60 ± 13.31), for SEM (101.92 ± 23.03), and for SM (113.44 ± 14.68): the multiple comparisons between techniques found a significant difference between CT and SM (P < 0.001), and SEM and SM (P = 0.025). When materials were compared within each measuring technique, Co-Cr showed lower values compared to zirconia in SEM (P < 0.001) and Stereo (P = 0.049); similar results were found in CT. CONCLUSIONS Results values differed with the chosen measuring technique. Co-Cr prostheses had a better fit than zirconia prostheses in SEM and Stereo. µCT showed comparable results to SEM, smaller than SM results.
Collapse
Affiliation(s)
- Elie E. Daou
- Department of Prosthodontics, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon
- Department of Fixed Prosthodontics, Faculty of Dentistry, Saint Joseph University, Beirut, Lebanon
| | - Pascale Salameh
- Department of Public Health, Faculty of Medical Sciences, Lebanese University, Beirut, Lebanon
| |
Collapse
|
7
|
Daou EE. Effect of lamination layer thickness and abutment preparation on the fit of Co-Cr multi-unit prostheses fabricated by additive manufacturing: An in vitro study. J Prosthet Dent 2024; 131:652-657. [PMID: 35430049 DOI: 10.1016/j.prosdent.2022.02.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 02/04/2022] [Accepted: 02/04/2022] [Indexed: 11/19/2022]
Abstract
STATEMENT OF PROBLEM Selective laser melting has been increasingly used in the fabrication of metal-ceramic prostheses. The lamination layer thickness may influence the fit of the restoration. However, data regarding its impact remain scarce. PURPOSE The purpose of this in vitro study was to evaluate the marginal and internal fit of cobalt-chromium (Co-Cr) 3-unit frameworks fabricated by additive manufacturing with different melting layer thicknesses on different abutments. MATERIAL AND METHODS The first right maxillary premolar and molar from a typodont were prepared with a circumferential 1.2-mm chamfer, 2-mm occlusal reduction, and total taper of 8 degrees to receive 3-unit fixed partial dentures. After framework design, the data were sent to a laser machine, and 30 specimens were fabricated from Co-Cr metal powder (Mediloy S-Co) by selective laser melting. Specimens were assigned to 3 groups (n=10) with different lamination layer thicknesses of 25 (L25), 50 (L50), and 100 (L100) μm. Marginal fit and internal fit were evaluated. Results were compared among layer thickness groups and abutments. Data were compared by using the Levene test, t test, and ANOVA (α=.05). RESULTS A statistical difference was found between different layer thickness groups (P=.016), but not between abutments (P=.429). On the abutment level, significant difference was found in the gap values for the molars (P=.049) between layer thickness groups, but not for the premolars (P=.126). Group L25 reported the smallest mean discrepancy values, and group L100 reported the highest, with statistical difference found between group L100 and groups L25 (P<.001) and L50 (P<.025), but not between groups L25 and L50 (P=.094). CONCLUSIONS The lamination layer thickness affected the adaptation of the metal frameworks. Framework fit did not significantly differ between abutments.
Collapse
Affiliation(s)
- Elie E Daou
- Assistant Professor, Department of Prosthodontics, School of Dentistry, Lebanese University, Beirut, Lebanon; Assistant Professor, Al-Ayen University, Nile Street, Nasiriyah.
| |
Collapse
|
8
|
Amalorpavam V, Chandramohan G, Soundar J, Shankar K, Missier MS, Hines AJ. Stereomicroscope-Based in Vitro Study Evaluating the Marginal and Internal Fit of PEEK and PEKK Crowns. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2024; 16:S1404-S1408. [PMID: 38882827 PMCID: PMC11174236 DOI: 10.4103/jpbs.jpbs_756_23] [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: 08/27/2023] [Revised: 08/27/2023] [Accepted: 10/03/2023] [Indexed: 06/18/2024] Open
Abstract
Purpose The aim of the in vitro study was to compare the internal merge and marginal perfection of polyetheretherketone (PEEK) and polyetherketoneketone (PEKK) crowns under a stereomicroscope. Methods All-ceramic preparation is done on the maxillary first premolar which is mounted on the wax block which was scanned using 3Shape scanner and duplicated into 30 acrylic CAD/CAM dies (n = 15) for the placement of PEEK and PEKK crowns. The YENADENT milling system was used to fabricate 15 samples from Group A PEEK crowns and to fabricate 15 samples from Group B PEKK crowns. According to the manufacturer's instructions, an equal amount of the dual-cure resin luting agent (Rely X U200 Self-Adhesive resin, 3M, Germany) was dispensed on the mixing pad before being mixed with cement and painted on the internal surfaces of the copings with the finger pressure crowns which were luted. The values were then analyzed using one-way ANOVA (post hoc) followed by Dunnett's t-test. Results Among those two groups, PEEK group materials showed the lowest mean value of (28.73.3 ± 4.01) for marginal fit and (26.72 ± 2.53) for internal gap, whereas PEKK group showed a mean value of (32.85 ± 4.63) and (33.06 ± 4.14), respectively. Conclusion Among these two groups, comparatively less marginal fit and internal adaptation is seen in PEKK when compared to the PEEK crowns. While the marginal fit and internal adaptation of both PEEK and PEKK copings were in acceptable clinical range.
Collapse
Affiliation(s)
- V Amalorpavam
- Assistant Professor, Department of Prosthodontics, Rajas Dental College and Hospital, Kavalkinaru, Tirunelveli, Tamil Nadu, India
| | - Giri Chandramohan
- Head of the Department and Professor, Department of Prosthodontics, Sree Mookambika Institute of Dental Sciences, Kulsekaram, Kanyakumari, India
| | - Joephin Soundar
- Assistant Professor, Department of Prosthodontics, Rajas Dental College and Hospital, Kavalkinaru, Tirunelveli, Tamil Nadu, India
| | - Kamala Shankar
- Associate Professor, Department of Prosthodontics, Chettinad Dental College, Chennai, India
| | - Mary Sheloni Missier
- Assistant Professor, Department of Orthodontics, Rajas Dental College and Hospital, Kavalkinaru, Tirunelveli, Tamil Nadu, India
| | - Allen Jim Hines
- Associate Professor, Department of Prosthodontics, Sree Mookambika Institute of Dental Sciences, Kavalkinaru, Tirunelveli, Tamil Nadu, India
| |
Collapse
|
9
|
Klimek L, Bułhak B, Śmielak B. A Comparison of the Structure and Selected Mechanical Properties of Cr/Co Alloys Obtained by Casting and Selective Laser Melting. J Funct Biomater 2024; 15:61. [PMID: 38535254 PMCID: PMC10970936 DOI: 10.3390/jfb15030061] [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: 12/29/2023] [Revised: 02/09/2024] [Accepted: 02/23/2024] [Indexed: 06/27/2024] Open
Abstract
Selective laser melting (SLM) technologies are becoming increasingly popular. The aim of the work is to compare the metallographic structure, hardness, and selected strength properties of alloys obtained by casting and by SLM, with a particular emphasis on fatigue strength. Twenty Cr/Co alloy bars were made by casting or SLM, and samples of appropriate dimensions were prepared for individual tests. The microstructures of the samples were tested by metallography, and then tested for hardness, impact strength, tensile strength, bending strength, and fatigue strength; they were also subjected to fracture after bending, tensile, fatigue, and impact tests, with the resulting fractures examined by scanning electron microscopy (SEM). Primary dendrites and small amounts of gas bubbles were present in the cast samples ground lengthwise. The SEM samples were more finer grained and uniform. Compared to the casting samples, the SLM samples demonstrated higher hardness, lower mean impact strength and higher tensile strength. The casting samples also displayed lower mean elongation values. The casting samples demonstrated slightly higher fatigue strength. The fractures of the casting samples showed an interdendritic character with clearly visible dendrites at the fracture, while those of the SLM samples were also intergranular, but finer grained. SLM generally results in better strength properties, while casting obtains slightly greater fatigue strength.
Collapse
Affiliation(s)
- Leszek Klimek
- Institute of Materials Science and Engineering, Lodz University of Technology, 90-924 Lodz, Poland;
| | - Barbara Bułhak
- Department of Dental Techniques, Medical University of Lodz, ul. Pomorska 251, 92-231 Lodz, Poland;
| | - Beata Śmielak
- Department of Prosthodontics, Medical University of Lodz, ul. Pomorska 251, 92-231 Lodz, Poland
| |
Collapse
|
10
|
Arslan S, Karagön M, Balkaya H, Köse B. A randomized clinical study evaluating the 30-month clinical performance of class II indirect restorations in endodontically treated teeth using ceramic, hybrid, and composite computer-aided design/computer-aided production blocks. JOURNAL OF CONSERVATIVE DENTISTRY AND ENDODONTICS 2024; 27:68-75. [PMID: 38389739 PMCID: PMC10880482 DOI: 10.4103/jcde.jcde_213_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 10/29/2023] [Accepted: 10/31/2023] [Indexed: 02/24/2024]
Abstract
Context Background In the literature, the information about which indirect material is the most appropriate for the restoration of endodontically treated teeth is insufficient. Therefore, studies evaluating the clinical performance of root canal-treated teeth will shed light on this issue for clinicians. Aim This clinical study aimed to evaluate the clinical performances of class II indirect restorations using ceramic, hybrid, and composite blocks to endodontically treated teeth. Materials and Methods A total of 60 indirect class II restorations were performed in 51 patients using Cerasmart (GC Dental Products Europe, Leuven, Belgium) composite, IPS e.max computer-aided design CAD (Ivoclar Vivadent, Schaan, Liechtenstein) ceramic, and Vita Enamic (Vita Zahnfabrik, Bad Sackingen, Germany) hybrid blocks. All the restored teeth had root canal treatment. The restorations were evaluated using modified FDI criteria for 30 months. Statistical Analysis Used The data were analyzed using Kruskal-Wallis analysis and Friedman two-way analysis of variance. Results A total of 53 restorations of the 60 restorations could be followed up at the end of 30 months. No statistically significant difference was observed between the groups after 30 months in terms of all criteria evaluated (P > 0.05). Conclusion Composite, ceramic, and hybrid blocks showed successful clinical performance in endodontically treated posterior teeth with large material loss.
Collapse
Affiliation(s)
- Soley Arslan
- Department of Restorative Dentistry, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| | - Mehmet Karagön
- Department of Restorative Dentistry, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| | - Hacer Balkaya
- Department of Restorative Dentistry, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| | - Burak Köse
- Department of Restorative Dentistry, Faculty of Dentistry, Erciyes University, Kayseri, Turkey
| |
Collapse
|
11
|
Yun Y, Kang H, Kim EC, Park S, Lee YS, Yun K. Fundamental Properties and Clinical Application of 3D-Printed Bioglass Porcelain Fused to Metal Dental Restoration. Int J Mol Sci 2023; 24:ijms24087203. [PMID: 37108364 PMCID: PMC10138347 DOI: 10.3390/ijms24087203] [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: 02/28/2023] [Revised: 03/29/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
The purpose of this study is to evaluate the mechanical properties and clinical fitness of 3D-printed bioglass porcelain fused to metal (PFM) dental crowns. To evaluate the mechanical properties, tensile strength, Vickers microhardness, shear bond strength, and surface roughness tests of the SLM printed Co-Cr alloy was conducted. A right mandibular 1st molar tooth was prepared for a single dental crown (n = 10). For a three-unit metal crown and bridge, the right mandibular first premolar and first molar were prepared. Bioglass porcelain was fired to fabricate PFM dental restorations. A clinical gap was observed and measured during each of the four times porcelain was fired. A statistical analysis was conducted. The SLM technique showed the largest statistically significant tensile strength and a 0.2% yield strength value. The milling technique had the lowest statistically significant compressive strength value. The shear bond strength and surface roughness showed no statistically significant difference between the fabricated method. There was a statistically significant change in marginal discrepancy according to the porcelain firing step. The casting technique showed the greatest statistically significant margin discrepancy value. The SLM method showed better fitness than the traditional casting method and showed better mechanical properties as a dental material.
Collapse
Affiliation(s)
- Yangan Yun
- Department of Prosthodontics, School of Dentistry, Chonnam National University, 33 Yongbongro, Bukgu, Gwangju 61186, Republic of Korea
| | - Hyeon Kang
- Department of Prosthodontics, School of Dentistry, Chonnam National University, 33 Yongbongro, Bukgu, Gwangju 61186, Republic of Korea
- Ace Dental Clinic, 56, Namak 3-ro, Samhyang-eup, Muan-gun 58567, Republic of Korea
| | - Eun-Chae Kim
- Department of Dental Laboratory Technology, Gwangju Health University, 73, Bungmun-daero 419beon-gil, Gwangsan-gu, Gwangju 62287, Republic of Korea
| | - Sangwon Park
- Department of Prosthodontics, School of Dentistry, Chonnam National University, 33 Yongbongro, Bukgu, Gwangju 61186, Republic of Korea
| | - Yong-Seok Lee
- Department of Mechanical Engineering, Myeongji University, Yongin 17058, Republic of Korea
| | - Kwidug Yun
- Department of Prosthodontics, School of Dentistry, Chonnam National University, 33 Yongbongro, Bukgu, Gwangju 61186, Republic of Korea
| |
Collapse
|
12
|
Mertsöz B, Ongun S, Ulusoy M. In-Vitro Investigation of Marginal Adaptation and Fracture Resistance of Resin Matrix Ceramic Endo-Crown Restorations. MATERIALS (BASEL, SWITZERLAND) 2023; 16:2059. [PMID: 36903174 PMCID: PMC10004208 DOI: 10.3390/ma16052059] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
The aim of this study was to evaluate the fracture resistance and marginal adaptation of endo-crown restorations produced from different resin-matrix ceramics (RMS) and the effects of these materials on marginal adaptation and fracture resistance. Three frasaco models were used by preparing (first) premolar teeth in three different margin preparations: butt-joint, heavy chamfer and shoulder. Each group was further divided into four subgroups according to the type of restorative material used: Ambarino High Class (AHC), Voco Grandio (VG), Brilliant Crios (BC) and Shofu (S) (n = 30). Master models were obtained using an extraoral scanner and fabricated with a milling machine. Marginal gap evaluation was performed with a silicon replica technique using a stereomicroscope. Replicas of the models (n = 120) were produced with epoxy resin. The fracture resistance of the restorations was recorded using a universal testing machine. The data were statistically analyzed using two-way ANOVA, and a t-test was applied for each group. Tukey's post-hoc test was performed to compare significant differences (p ≤ 0.05). The highest marginal gap was observed in VG, and the best marginal adaptation and the highest fracture resistance were found in BC. The lowest fracture resistance in Butt-joint preparation design was found in S. In addition, the lowest fracture resistance value in the heavy chamfer preparation design was found in AHC. The heavy shoulder preparation design displayed the highest fracture resistance values for all materials.
Collapse
Affiliation(s)
- Burak Mertsöz
- Department of Prosthodontics, Faculty of Dentistry, Near East University, Mersin 10, Lefkosa 99040, Turkey
| | - Salim Ongun
- Department of Prosthodontics, Faculty of Dentistry, Final International University, Nicosia 99010, Turkey
| | - Mutahhar Ulusoy
- Department of Prosthodontics, Faculty of Dentistry, Near East University, Mersin 10, Lefkosa 99040, Turkey
| |
Collapse
|
13
|
Daou EE, Baba NZ. The Effect of Firing Cycles on the Fit of Cobalt-Chromium Multiunit Prostheses Fabricated by Additive Manufacturing. J Prosthodont 2023; 32:71-76. [PMID: 35304798 DOI: 10.1111/jopr.13506] [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: 09/08/2021] [Accepted: 03/02/2022] [Indexed: 01/25/2023] Open
Abstract
PURPOSE The effect of annealing and firing cycle on the adaptation of cobalt-chromium (CoCr) restorations fabricated by additive manufacturing has been poorly documented. This study compared the marginal and internal fit of CoCr three-unit fixed dental prostheses before and after firing cycles. MATERIAL AND METHODS The first right maxillary premolar (MP) and molar (MM) on a typodont model, were prepared with a circumferential 1.2 mm chamfer, 2 mm occlusal reduction, and total taper of 8 degrees, to receive 3-unit fixed dental prostheses (FDP). After the framework design, 20 framework specimens were fabricated using CoCr metal powder by selective laser melting. The replica technique was used for marginal and internal fit measurements in mesiodistal and buccolingual planes. The specimens were submitted to an annealing process, and to ceramic firing protocol. Measurements were repeated after each firing cycle. The data were compared by using Levene test, t-test, and analysis of variance (ANOVA) (α = 0.05). RESULTS A significant difference was found in the total intaglio surface discrepancy between the 3 treatments. The annealing treatment induced a statistical difference in the discrepancy value compared to the as printed state (p = 0.028). A significant difference was detected between the initial manufacturing phase and the ceramic layering firing cycle (p = 0.003). CONCLUSIONS Firing cycles induced an alteration of the frameworks adaptation.
Collapse
Affiliation(s)
- Elie E Daou
- Department of Prosthodontics, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon.,Al-Ayen University, Nile Street, Nasiriyah
| | - Nadim Z Baba
- Advanced Specialty Education Program in Implant Dentistry, Loma Linda University, School of Dentistry, California, USA
| |
Collapse
|
14
|
Findrik Balogová A, Rajťúková V, Chromý Ľ, Somoš A, Ižaríková G, Hudák R. Biomechanical Testing of Two-Unit Bridges and a Comparison of Replacement Retention Depending on a Cementation Medium, Replacement Position, and Gap Size. J Funct Biomater 2022; 13:jfb13040286. [PMID: 36547547 PMCID: PMC9788551 DOI: 10.3390/jfb13040286] [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: 10/20/2022] [Revised: 11/21/2022] [Accepted: 12/04/2022] [Indexed: 12/13/2022] Open
Abstract
Dental replacements are placed between the abutment teeth. The exceptions are two-unit bridges, as they are supported by a single tooth prepared only on one side of the missing tooth. The presented study deals with an analysis of a pressure force action on two-unit bridges placed in the frontal part (20 samples), where the pressure action is lower, and in the distal part (20 samples), where the pressure action is higher. A CAD program by 3Shape was used for digital designing with two different gap settings, 10 μm (20 samples) and 30 μm (20 samples). Two-unit bridges were attached to the prepared tooth using two types of dental cement (20/20 samples), which were selected for their physical and bioactive properties. All two-unit bridges (a total of 80 samples) were fabricated from CoCr alloys on Mlab cusing R by applying the Selective Laser Melting (SLM) technology. Mechanical testing was performed using the Inspekt5 table blue. The obtained data were used to verify the hypotheses-a difference between both types of cement (A ≠ B), a difference between the frontal and distal two-unit bridges (F ≠ D) and a difference between the gap sizes (10 ≠ 30). To confirm the given theories, data were statistically evaluated using the F-test and subsequent t-tests. The resulting p-value was compared with the level of significance (α = 0.05). A statistical evaluation revealed a significant difference between the compared groups; however, no explicit correlation between the individual groups of specimens was identified.
Collapse
Affiliation(s)
- Alena Findrik Balogová
- Department of Biomedical Engineering and Measurement, Faculty of Mechanical Engineering, Technical University of Košice, 040 01 Košice, Slovakia
| | - Viktória Rajťúková
- Department of Biomedical Engineering and Measurement, Faculty of Mechanical Engineering, Technical University of Košice, 040 01 Košice, Slovakia
- Correspondence:
| | - Ľuboš Chromý
- Department of Biomedical Engineering and Measurement, Faculty of Mechanical Engineering, Technical University of Košice, 040 01 Košice, Slovakia
| | - Andrej Somoš
- Clinic of Pneumology and Phthisiology, L. Pasteur University Hospital Košice, 040 11 Košice, Slovakia
| | - Gabriela Ižaríková
- Department of Applied Mathematics and Informatics, Faculty of Mechanical Engineering, Technical University of Košice, 040 01 Košice, Slovakia
| | - Radovan Hudák
- Department of Biomedical Engineering and Measurement, Faculty of Mechanical Engineering, Technical University of Košice, 040 01 Košice, Slovakia
| |
Collapse
|
15
|
Dzięgielewski M, Regulska K, Korycki R, Klimek L. Analysis of Stress and Displacement Fields in Prosthetic Crowns Made of Zirconium Dioxide Using Numerical Approach of Homogenization Hypothesis. MATERIALS (BASEL, SWITZERLAND) 2022; 15:7716. [PMID: 36363304 PMCID: PMC9656074 DOI: 10.3390/ma15217716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
The main goal of this paper is to analyze the stress and displacement fields in prosthetic crowns made of zirconium dioxide using the numerical approach of homogenization hypothesis. The simple engineering model is developed and applied in case of vertical forces. The model is a three-dimensional simulation of molars subjected to crushing, mastication, and clenching. Two basic approaches are considered: the single prosthetic crown on a single molar, and the prosthetic bridge on two molars. The distributions of material parameters are determined for the rigid support and the elastic gum structure of the homogenized properties. The crown on a single molar is analyzed in respect of caries, which are represented by weak material parameters. Irrespective of the problem, the maximal stresses are always insignificant compared to the compressive strength for enamel, dentin, periodontium, and zirconium dioxide. In case of caries, the maximal stresses are located at the contact surface caries/crown, whereas the displacement was higher than the same parameter without caries. The stresses inside the prosthetic bridge on two molars were comparable for elastic and rigid support, and located at the same areas. The molar displacement for elastic gum was higher than for the rigid base, and additionally supplemented by the displacement of the supporting structure.
Collapse
Affiliation(s)
- Michał Dzięgielewski
- Department of Mechanical Engineering, Informatics and Chemistry of Polymer Materials, Lodz University of Technology, Żeromskiego 116, 90-924 Lodz, Poland
| | - Kinga Regulska
- Interdisciplinary Doctoral School, Lodz University of Technology, Żeromskiego 116, 90-924 Lodz, Poland
| | - Ryszard Korycki
- Department of Mechanical Engineering, Informatics and Chemistry of Polymer Materials, Lodz University of Technology, Żeromskiego 116, 90-924 Lodz, Poland
| | - Leszek Klimek
- Institute of Materials Science and Engineering, Lodz University of Technology, Żeromskiego 116, 90-924 Lodz, Poland
| |
Collapse
|
16
|
Addugala H, Venugopal VN, Rengasamy S, Yadalam PK, Albar NH, Alamoudi A, Bahammam SA, Zidane B, Bahammam HA, Bhandi S, Shrivastava D, Srivastava KC, Patil S. Marginal and Internal Gap of Metal Copings Fabricated Using Three Types of Resin Patterns with Subtractive and Additive Technology: An In Vitro Comparison. MATERIALS (BASEL, SWITZERLAND) 2022; 15:6397. [PMID: 36143710 PMCID: PMC9506594 DOI: 10.3390/ma15186397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Revised: 09/07/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
This study analyzes the evidence of the marginal discrepancy and internal adaptation of copings fabricated using three types of resin patterns with subtractive (milling) and additive technology (3D printing), as it is not widely reported. Working casts (n = 15) were scanned and patterns were completed using computer-aided designing (CAD). Resin patterns were fabricated using the designed data and divided into three groups according to the method of fabrication of patterns: subtractive technology-CAD milled polymethyl methacrylate resin (Group-PMMA), additive technology [digital light processing (DLP) technique]-acrylonitrile-butadiene-styrene (ABS) patterns (Group-ABS), and polylactic acid (PLA) patterns (Group-PLA). Resin patterns were casted with Cobalt-Chromium (Co-Cr) alloy (lost wax technique). Internal and marginal gaps of the metal copings were analyzed with the replica technique under optical microscope. The Kruskal-Wallis test was used to compare values among the groups, and post hoc multiple tests confirmed the specific differences within the groups. The median marginal gap was least for CAD milled resin patterns, followed by PLA printed resin patterns and ABS printed resin patterns. There were significant differences between Group-PMMA and Group-PLA and Group-ABS (p = 0.0001). There was no significant difference between Group-PLA and Group-ABS (p = 0.899). The median internal gap was least for metal copings fabricated from Group-PLA, followed by Group-ABS and Group-PMMA. The differences were not statistically significant (p = 0.638) for the internal gap. Full metal Co-Cr copings fabricated from the milled PMMA group had a better marginal fit, followed by the PLA and ABS printed groups. Copings fabricated with the PLA printed group had the best internal fit, though the values were statistically insignificant between the groups.
Collapse
Affiliation(s)
- Hemavardhini Addugala
- Department of Prosthodontics and Implantology, SRM Kattankulathur Dental College and Hospital, SRM Institute of Science and Technology, SRM Nagar, Chennai 603203, India
- Independent Researcher, Chennai 603203, India
| | - Vidyashree Nandini Venugopal
- Department of Prosthodontics and Implantology, SRM Kattankulathur Dental College and Hospital, SRM Institute of Science and Technology, SRM Nagar, Chennai 603203, India
| | - Surya Rengasamy
- Department of Prosthodontics and Implantology, SRM Kattankulathur Dental College and Hospital, SRM Institute of Science and Technology, SRM Nagar, Chennai 603203, India
| | - Pradeep Kumar Yadalam
- Department of Periodontics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai 602117, India
| | - Nassreen H. Albar
- Department of Restorative Dental Sciences, Division of Operative Dentistry, College of Dentistry, Jazan University, Jazan 45142, Saudi Arabia
| | - Ahmed Alamoudi
- Department of Oral Biology, King Abdulaziz University, P.O. Box 80209, Jeddah 21589, Saudi Arabia
| | - Sarah Ahmed Bahammam
- Department of Pediatric Dentistry and Orthodontics, College of Dentistry, Taibah University, P.O. Box 344, Medina 42353, Saudi Arabia
| | - Bassam Zidane
- Department of Restorative Dentistry, King Abdulaziz University, P.O. Box 80209, Jeddah 21589, Saudi Arabia
| | - Hammam Ahmed Bahammam
- Department of Pediatric Dentistry, College of Dentistry, King Abdulaziz University, P.O. Box 80209, Jeddah 21589, Saudi Arabia
| | - Shilpa Bhandi
- Department of Restorative Dental Sciences, Division of Operative Dentistry, College of Dentistry, Jazan University, Jazan 45142, Saudi Arabia
- Department of Cariology, Saveetha Dental College & Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai 600077, India
| | - Deepti Shrivastava
- Department of Preventive Dentistry, College of Dentistry, Jouf University, Sakaka 72388, Saudi Arabia
| | - Kumar Chandan Srivastava
- Department of Oral & Maxillofacial Surgery & Diagnostic Sciences, College of Dentistry, Jouf University, Sakaka 72345, Saudi Arabia
| | - Shankargouda Patil
- Department of Maxillofacial Surgery and Diagnostic Science, Division of Oral Pathology, College of Dentistry, Jazan University, Jazan 45142, Saudi Arabia
- Centre of Molecular Medicine and Diagnostics (COMManD), Saveetha Dental College & Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai 600077, India
| |
Collapse
|
17
|
Aydın N, Ekren O, Kocak EF, Ucar Y. Comparison of the Marginal and Internal Discrepancy of Metal-Ceramic Restorations Produced by Milling for Soft Metal, Direct Metal Laser Sintering and Casting Methods: An In Vitro Study. JOURNAL OF ADVANCED ORAL RESEARCH 2022. [DOI: 10.1177/23202068221103980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Aim: To evaluate the effect of ceramic firing cycles on the internal and marginal discrepancy of restorations fabricated using conventional lost wax casting (LW), direct metal laser sintering (DMLS), and milling for soft metal (MS). Materials and Methods: A total of 45 restorations were produced by LW, DMLS, and MS methods ( n = 15), according to the digital impression on the metal die representing the prepared first molar. The internal discrepancy (ID) was measured through the silicon weight method and the marginal discrepancy (MD) was measured using a light microscope. ID and MD measurements were repeated following the metal manufacturing, ceramic application, and glazing. Statistical analyses were conducted by means of two-way analysis of variance and Tukey-HSD ( α = 0.05) tests. Results: Statistically significant differences were found between the fabrication methods ( P ≤ 0.001) both for MD and ID. The mean MD values of the restorations were 31.4 ± 13.8 µm for MS, 20.8 ± 14.4 µm for LW, and 7.3 ± 6 µm for DMLS. A statistically significant increase was observed in the mean MD values of metal frameworks ( P ≤ 0.001) following ceramic and glaze applications. However, no statistically significant difference was found between the ceramic and the glaze applied stages ( P = .072). The mean ID values were 37 ± 5.7 mg for LW, 28 ± 6.1 mg for DMLS, and 21.6 ± 7.3 mg for MS. Unlike the manufacturing method, ceramic firing cycles had no effects on the ID ( P > 0.05). Conclusion: MS had the highest mean MD, but it had the lowest ID. The ceramic firing had a significantly negative effect only on MD.
Collapse
Affiliation(s)
- Nazlı Aydın
- Department of Prosthetic Dentistry, Faculty of Dentistry, Cukurova University, Balcali, Adana, Turkey
- Abdi Sutcu Vocational School of Health Services, Cukurova University, Balcali, Adana, Turkey
| | - Orhun Ekren
- Department of Prosthetic Dentistry, Faculty of Dentistry, Cukurova University, Balcali, Adana, Turkey
- Department of Advanced Materials and Nanotechnology, Institute of Natural and Applied Sciences, Cukurova University, Balcali, Adana, Turkey
| | - Elif Figen Kocak
- Department of Prosthetic Dentistry, Faculty of Dentistry, Cukurova University, Balcali, Adana, Turkey
- Abdi Sutcu Vocational School of Health Services, Cukurova University, Balcali, Adana, Turkey
| | - Yurdanur Ucar
- Private Dental Practice, Motto Oral and Dental Health Polyclinic, Antalya, Turkey
| |
Collapse
|
18
|
Comparison of four CAD-CAM guides for preparing guiding planes of removable partial dentures. Comput Biol Med 2022; 146:105564. [DOI: 10.1016/j.compbiomed.2022.105564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 11/18/2022]
|
19
|
Comparison of Microleakage in Nanocomposite and Amalgam as a Crown Foundation Material Luted with Different Luting Cements under CAD-CAM Milled Metal Crowns: An In Vitro Microscopic Study. Polymers (Basel) 2022; 14:polym14132609. [PMID: 35808655 PMCID: PMC9269321 DOI: 10.3390/polym14132609] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/16/2022] [Accepted: 06/23/2022] [Indexed: 02/04/2023] Open
Abstract
Microleakage is a persistent problem despite advancement in materials and techniques in fixed prosthodontics. This leads to the importance of sound crown foundation material and luting agents used to maintain the marginal seal. The literature is deficient with studies, comparing microleakage under various crown foundation materials and luting agents, especially with CAD-CAM (computer-aided design and computer-aided manufacturing) metal crowns. This study was aimed to compare microleakage in a nanocomposite/dentinal bonding agent and amalgam/cavity varnish as crown foundation materials luted with two different luting cements: resin-reinforced glass ionomer cement and self-adhesive resin cement, under both dry and contaminated conditions. A hundred intact, caries-free human molars were prepared to receive crown foundation material and extra coronal restorations. Amalgams with cavity varnish and nanocomposites with dentinal bonding agent in both ideal and contaminated conditions were used as crown foundation materials. After restoration, each sample was cemented with a CAD-CAM milled metal crown using two different luting agents—resin-reinforced glass ionomer cement and self-adhesive resin cements both in ideal and contaminated conditions. Cementation was followed by thermocycling of samples, immersion in erythrosine B dye, embedding in clear auto polymerizing acrylic resin and sectioning to evaluate microleakage using stereomicroscope. The mean microleakage between different luting cements on the experimental side of the facial surface was 137.64 μm and 211.01 μm for resin-reinforced GIC and for self-adhesive resin cement was 119.78 μm and 150.42 μm, under ideal and contaminated condition, respectively. There was a significant difference in mean micro-leakage between different crown foundation material and cement groups used in the study. The composites and amalgam, both when used as crown foundation material and luted with use of technically advanced CAD-CAM metal crown with self-adhesive resin cement (in both ideal or contaminated condition), showed less microleakage than in resin-reinforced glass ionomer cement. Overall, the self-adhesive resin cement showed comparatively reduced microleakage in all combinations with different crown foundations. Thus, this combination can be used in daily clinical practice to provide better protection from further decay.
Collapse
|
20
|
Almodalal MA, Morad ML, Hajeer MY, Harfouche M. Comparative Evaluation of Two Different Types of Abutments in Relation to Post-prosthetic Bone Resorption and Periodontal Pocket Depth: A Randomized Controlled Clinical Trial With a One-Year Follow-Up. Cureus 2022; 14:e25807. [PMID: 35698469 PMCID: PMC9185182 DOI: 10.7759/cureus.25807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2022] [Indexed: 11/05/2022] Open
|
21
|
Comparison of the Accuracy between Denture Bases Produced by Subtractive and Additive Manufacturing Methods: A Pilot Study. PROSTHESIS 2022. [DOI: 10.3390/prosthesis4020015] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Today, two different types of CAD-CAM fabrication methods for complete denture bases are available besides the conventional protocols: a subtractive milling process from a prepolymerized block of polymethylmethacrylate and an additive manufacturing process that built the denture base using a light-cured liquid in a VAT-polymerization process. The aim of this study was to evaluate and to compare the accuracy and precision of denture prosthetic bases made with subtractive and additive manufacturing technologies and to compare them with a denture base with the conventional method in muffle. From the results obtained, 3D printing dentures show a statistically significant higher accuracy than milled prosthetic bases. Milled prosthetic bases have similar accuracy than conventional fabricated dentures.
Collapse
|
22
|
Lim J, Bae EJ, Kim JH. Evaluation of internal fit of press ceramic and porous structured cobalt–chromium crown fabricated by additive manufacturing. Dent Res J (Isfahan) 2022. [DOI: 10.4103/1735-3327.353834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
|
23
|
Karapetyan AA, Ukhanov MM, Ryakhovsky AN. [Metal 3D printing in dentistry]. STOMATOLOGIIA 2022; 101:85-91. [PMID: 36268927 DOI: 10.17116/stomat202210105185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The article describes the use of 3D printing in dentistry, the principle of operation of 3D printers for metals, a review of comparative data on the quality and accuracy of the final product of 3D metal printing is carried out. Possibilities and prospects of using 3D metal printing in dentistry are indicated.
Collapse
Affiliation(s)
- A A Karapetyan
- Central Research Institute of Dental and Maxillofacial Surgery, Moscow, Russia
| | - M M Ukhanov
- Central Research Institute of Dental and Maxillofacial Surgery, Moscow, Russia
| | - A N Ryakhovsky
- Central Research Institute of Dental and Maxillofacial Surgery, Moscow, Russia
| |
Collapse
|
24
|
Amalorpavam V, Sreelal T, Chandramohan G, Jithin GN, Ponjayanthi, Kamalashankar. Comparison of Marginal Fit and Internal Adaptation of Copings Fabricated with Polyetheretherketone and Zirconia - An In vitro Study. J Pharm Bioallied Sci 2021; 13:S1199-S1205. [PMID: 35017956 PMCID: PMC8686888 DOI: 10.4103/jpbs.jpbs_328_21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 04/16/2021] [Accepted: 04/23/2021] [Indexed: 12/04/2022] Open
Abstract
Context: Purpose: The aim of this in vitro study was to evaluate and compare the Marginal fit and Internal adaptation of copings fabricated with polyetheretherketone (PEEK) and Zirconia luted with resin cements. Materials and Methods: Maxillary first premolar was prepared to receive all ceramic restoration. It was duplicated using addition silicon impression material for fabricating Cobalt–Chromium metal die, which is used as a master die. Using the master die, 30 heat cure acrylic samples were fabricated for the heat cure acrylic tooth models on which 15 PEEK and 15 zirconia copings were made. Self-adhesive resin cement is used for luting and 30 copings were luted. After 24 h, luted copings were having a disc of thickness 0.01 mm cutting at high speed using a Tooth cutting lathe for all the 30 samples. Field Scanning Electron Microscopic study analysis for evaluating marginal fit and internal adaptation of two groups were observed. The values were then analyzed using one-way ANOVA (post hoc) followed by Dunnet t-test. Results: Among those two groups, PEEK copings group materials showed the lowest mean value of (30.3 ± 5.1) for marginal gap, (29.1 ± 5.8) for internal gap whereas the zirconia copings group showed a mean value of (50.26 ± 16.02) and (32.8 ± 5.2) respectively. Conclusion: Among these two groups, comparatively less marginal fit and internal adaptation is seen in zirconia copings when compared to the PEEK copings. While the marginal fit and internal adaptation of both PEEK and zirconia copings were in the acceptable clinical range.
Collapse
Affiliation(s)
- V Amalorpavam
- Assistant Professor, Department of Prosthodontics, Rajas Dental College and Hospital, Kavalkinaru, Tirunelveli, India
| | - T Sreelal
- Former Professor and Head of the Department, Department of Prosthodontics, Sree Mookambika Institute of Dental Sciences, Kulasekaram, Kanya Kumari, India
| | - Giri Chandramohan
- Professor, Department of Prosthodontics, Sree Mookambika Institute of Dental Sciences, Kulasekaram, Kanya Kumari, India
| | - G N Jithin
- Consultant Prosthodontist and Private Practioner, Smile Care Multispeciality Dental Clinic, Parassala, Trivandrum, India
| | - Ponjayanthi
- Assistant Professor, Department of Prosthodontics, Vivekanadha Dental College for Women, Tiruchengode, India
| | - Kamalashankar
- Assistant Professor, Department of Prosthodontics, Chettinad Dental College, Chennai, India
| |
Collapse
|
25
|
Comparison of the internal fit of metal crowns fabricated by traditional casting, computer numerical control milling, and three-dimensional printing. PLoS One 2021; 16:e0257158. [PMID: 34529710 PMCID: PMC8445422 DOI: 10.1371/journal.pone.0257158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 08/20/2021] [Indexed: 11/30/2022] Open
Abstract
This experimental study aimed to compare the internal fit (marginal fit and internal discrepancy) of metal crowns fabricated by traditional casting and digital methods (computer numerically controlled (CNC) milling and three-dimensional [3D] printing). Thirty standard master abutment models were fabricated using a 3D printing technique with digital software. Metal crowns were fabricated by traditional casting, CNC milling, and 3D printing. The silicon replica method was used to measure the marginal and internal fit. A thin layer of low-viscosity polyvinyl siloxane material was placed inside each crown and on the die (like a seat) until the material was set. Replicas were examined at four reference points under a microscope: the central pit (M1), cusp tip (M2), axial wall (M3), and margin (M4). The measured data were analyzed using a one-way analysis of variance (ANOVA) to verify statistical significance, which was set at p < 0.05. In the traditional casting group, the minimum distance measured was at M3 (90.68 ± 14.4 μm) and the maximum distance measured was at M1 (145.12 ± 22 μm). In the milling group, the minimum distance measured was at M3 (71.85 ± 23.69 μm) and the maximum distance measured was at M1 (108.68 ± 10.52 μm). In the 3D printing group, the minimum distance measured was at M3 (100.59 ± 9.26 μm) and the maximum distance measured was at M1 (122.33 ± 7.66 μm). The mean discrepancy for the traditional casting, CNC milling, and 3D printing groups was 120.20, 92.15, and 111.85 μm, respectively, showing significant differences (P < 0.05). All three methods of metal crown fabrication, that is, traditional casting, CNC milling, and 3D printing, had values within the clinically acceptable range. The marginal and internal fit of the crown was far superior in the CNC milling method.
Collapse
|
26
|
Kayikci O, Ates SM. Comparison of marginal and internal fit of three-unit implant-supported fixed prosthetic substructures fabricated using CAD/CAM systems. Clin Oral Investig 2021; 26:1283-1291. [PMID: 34331593 DOI: 10.1007/s00784-021-04102-4] [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] [Received: 03/09/2021] [Accepted: 07/23/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVE This study compared the marginal and internal fit of implant-supported fixed dentures fabricated using CAD/CAM systems. MATERIALS AND METHODS A lower jaw model representing partial edentulism was produced. Two dental implants were inserted in the area of teeth 35 and 37, onto which cemented abutments were screwed. The model was scanned using a laboratory scanner and transferred to a design software program for substructure fabrication. Sixty substructures were fabricated out of each group for six substructure types (n = 10), cast Co-Cr (control), milling Co-Cr, laser sintering Co-Cr, titanium (Ti), zirconium, and polyetheretherketone (PEEK) substructures. The marginal and internal fit was evaluated using a silicone replica viewed under a stereomicroscope. The data were analyzed using the statistical package program for social sciences (SPSS, Chicago, IL, USA, v. 17) at a significance level of 0.05. Marginal and internal gaps were compared using the one-way ANOVA test and Tukey's post hoc test. The differences between abutment teeth were determined using the independent sample t-test. RESULTS There was a significant difference in the marginal gap between PEEK and Ti groups (p < 0.05) but no difference between other groups (p > 0.05). There was a significant difference in the internal gap between PEEK, laser sintering Co-Cr, and milling Co-Cr groups (p < 0.05) but no difference between other groups (p > 0.05). The PEEK group had a higher marginal gap than the Ti group and a higher internal gap than the DMLS Co-Cr group (p < 0.05). CONCLUSION All substructures have a marginal and internal fit within acceptable clinical limits. CLINICAL RELEVANCE This in vitro study suggests that materials and techniques used in CAD/CAM systems improve the fitting accuracy of implant-supported fixed restorations.
Collapse
Affiliation(s)
- Ozlem Kayikci
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey
| | - Sabit Melih Ates
- Department of Prosthodontics, Faculty of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey.
| |
Collapse
|
27
|
Schweiger J, Edelhoff D, Güth JF. 3D Printing in Digital Prosthetic Dentistry: An Overview of Recent Developments in Additive Manufacturing. J Clin Med 2021; 10:2010. [PMID: 34067212 PMCID: PMC8125828 DOI: 10.3390/jcm10092010] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/30/2021] [Accepted: 04/30/2021] [Indexed: 11/16/2022] Open
Abstract
Popular media now often present 3D printing as a widely employed technology for the production of dental prostheses. This article aims to show, based on factual information, to what extent 3D printing can be used in dental laboratories and dental practices at present. It attempts to present a rational evaluation of todays´ applications of 3D printing technology in the context of dental restorations. In addition, the article discusses future perspectives and examines the ongoing viability of traditional dental laboratory services and manufacturing processes. It also shows which expertise is needed for the digital additive manufacturing of dental restorations.
Collapse
Affiliation(s)
- Josef Schweiger
- Department of Prosthetic Dentistry, University Hospital, Ludwig-Maximilians University Munich, 80336 Munich, Germany;
| | - Daniel Edelhoff
- Department of Prosthetic Dentistry, University Hospital, Ludwig-Maximilians University Munich, 80336 Munich, Germany;
| | - Jan-Frederik Güth
- Poliklinik für Zahnärztliche Prothetik, Center for Dentistry and Oral Medicine (Carolinum), Goethe-University, 60596 Frankfurt am Main, Germany
| |
Collapse
|
28
|
Corrosion Resistance of Cr–Co Alloys Subjected to Porcelain Firing Heat Treatment—In Vitro Study. Processes (Basel) 2021. [DOI: 10.3390/pr9040636] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The procedure of ceramics fusion to cobalt–chromium (Co–Cr) base dental crowns affects their corrosion behavior and biological tolerance. This study’s purpose was to comparatively evaluate the effect of heat treatment (HT) applicable for dental ceramics firing on the corrosion properties among Co–Cr base alloys fabricated via different methods: casting (CST), milling soft metal and post sintering (MSM), and selective laser melting (SLM). All specimens were subjected to a heat treatment corresponding to a full firing schedule. The microstructure and elemental composition of oxidized surfaces were investigated by scanning electron microscopy and energy dispersive spectroscopy. Corrosion properties were examined by electrochemical potentiodynamic polarization tests. The values of jcorr, Ecorr, Rp, and breakdown potential Ebr were estimated. The oxide layers formed during the HT process corresponded to the composition of the original alloys’ structure. Among the thermal treated alloys, SLM showed the highest corrosion resistance, followed by the MSM and CST. This may be attributed to uniform distribution of alloying elements in homogenous structure and to the reduced porosity, which enhances corrosion resistance and decreases the risk of crevice corrosion. The overall corrosion behavior was strongly influenced by the segregation of alloying elements in the microstructure, thus, is directly determined by the manufacturing method.
Collapse
|
29
|
Song DB, Han MS, Kim SC, Ahn J, Im YW, Lee HH. Influence of Sequential CAD/CAM Milling on the Fitting Accuracy of Titanium Three-Unit Fixed Dental Prostheses. MATERIALS 2021; 14:ma14061401. [PMID: 33805802 PMCID: PMC7998422 DOI: 10.3390/ma14061401] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/08/2021] [Accepted: 03/10/2021] [Indexed: 12/02/2022]
Abstract
This study investigated the fitting accuracy of titanium alloy fixed dental prostheses (FDP) after sequential CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) fabrication. A three-unit FDP model connecting mandibular second premolars and molars was prepared and scanned to fabricate titanium FDPs by CAD/CAM milling. A total of six FDPs were sequentially milled in one titanium alloy disk using a new set of burs every time (n = 4). The fitting accuracy of FDPs was mesiodistally evaluated by a silicone replica technique and the measurement was triplicated at four different locations: MO (marginal opening), MG (marginal gap), AG (axial gap), and OG (occlusal gap). Data were statistically analyzed using ANOVA and Tukey’s HSD test. The fitting accuracy of PMMA (polymethyl methacrylate) FDPs milled using the worn or new bur were evaluated by the same procedure (n = 6). The mean dimensions of titanium FDP for all measuring positions, except for AG, were significantly increased from the third milling. However, no difference was noted between the first FDP and the second FDP milled with the same set of burs. Severe edge chippings were observed in all milling burs. Detrimental effects of the worn burs on the fitting accuracy were demonstrated in the CAD/CAM-milled PMMA FDP. The results recommend proper changing frequency of cutting burs to achieve the quality of fit and predictable outcomes for dental CAD/CAM prostheses.
Collapse
Affiliation(s)
- Doo-Bin Song
- Department of Biomaterials Science, College of Dentistry, Dankook University, 119 Dandaero, Cheonan 31116, Korea; (D.-B.S.); (J.A.)
- Department of Dental Laboratory Technology, Daejeon Health Institute of Technology, Daejeon 34504, Korea;
| | - Man-So Han
- Department of Dental Laboratory Technology, Daejeon Health Institute of Technology, Daejeon 34504, Korea;
| | - Si-Chul Kim
- Department of Dental Laboratory Technology, Chungbuk Health & Science University, Cheongju 28150, Korea;
| | - Junyong Ahn
- Department of Biomaterials Science, College of Dentistry, Dankook University, 119 Dandaero, Cheonan 31116, Korea; (D.-B.S.); (J.A.)
| | - Yong-Woon Im
- Department of Dental Laboratory, Kyungdong University, Wonju 26495, Korea;
| | - Hae-Hyoung Lee
- Department of Biomaterials Science, College of Dentistry, Dankook University, 119 Dandaero, Cheonan 31116, Korea; (D.-B.S.); (J.A.)
- Correspondence: ; Tel.: +82-41-550-1925
| |
Collapse
|
30
|
Wang C, Shi YF, Xie PJ, Wu JH. Accuracy of digital complete dentures: A systematic review of in vitro studies. J Prosthet Dent 2021; 125:249-256. [DOI: 10.1016/j.prosdent.2020.01.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/29/2020] [Accepted: 01/29/2020] [Indexed: 11/25/2022]
|
31
|
Daou EE. X-ray microtomographic evaluation of the absolute marginal fit of fixed prostheses made from soft Co-Cr and zirconia. J Prosthet Dent 2020; 127:289-294. [PMID: 33279157 DOI: 10.1016/j.prosdent.2020.07.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/23/2020] [Accepted: 07/23/2020] [Indexed: 11/30/2022]
Abstract
STATEMENT OF PROBLEM The absolute marginal fit of CAD-CAM presintered fixed partial dentures has been poorly documented. PURPOSE The purpose of this in vitro study was to evaluate the marginal fit of presintered cobalt-chromium (Co-Cr) and zirconia 3-unit fixed partial dentures by using X-ray microcomputed tomography (μCT). MATERIAL AND METHODS A metal model was prepared from a typodont to receive fixed partial dentures (N=12). The maxillary first premolar and first molar were prepared with a circumferential 1.2-mm chamfer and 2-mm occlusal reduction. The dies were scanned and assigned to 1 of 2 groups to receive the prostheses made of presintered Co-Cr or presintered zirconia (n=6). Each framework was seated on its model without load application. The abutments were scanned by using μCT. A circle with 10 diameters, with a step of 18 degrees, was projected at the center of the obtained image. Absolute marginal discrepancy and marginal gap mean values were measured, and overextended and underextended margins determined. The data were analyzed by using the Levene t test and ANOVA (α=.05). RESULTS No statistically significant difference was found in the marginal fit between the materials tested (P=.939). The mean values were 66 ±14 μm for Co-Cr and 61 ±12 μm for zirconia. The absolute marginal discrepancy mean value for the premolar was 69 ±12 μm and 41 ±9 μm for the molar (P<.001). Overextension was predominant for both materials tested, with a higher percentage reported for the zirconia group. CONCLUSIONS Presintered alloys presented clinically acceptable adaptation with a predominance of marginal overextensions.
Collapse
Affiliation(s)
- Elie E Daou
- Lecturer, Department of Prosthodontics Faculty of Dentistry, Faculty of Dental Medicine, Beirut, Lebanon.
| |
Collapse
|
32
|
Long-term clinical outcome of posterior metal-ceramic crowns fabricated with direct metal laser-sintering technology. J Prosthodont Res 2020; 64:354-357. [DOI: 10.1016/j.jpor.2019.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 07/08/2019] [Accepted: 10/07/2019] [Indexed: 11/23/2022]
|
33
|
Altintas MA, Akin H. Effect of repetitive firing on passive fit of metal substructure produced by the laser sintering in implant-supported fixed prosthesis. J Adv Prosthodont 2020; 12:167-172. [PMID: 32601536 PMCID: PMC7314632 DOI: 10.4047/jap.2020.12.3.167] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 03/07/2020] [Accepted: 03/20/2020] [Indexed: 12/02/2022] Open
Abstract
PURPOSE The aim of the present study was to investigate the passive fit of metal substructure after repetitive firing processes in implant-supposed prosthesis. MATERIALS AND METHODS Five implants (4 mm diameter and 10 mm length) were placed into the resin-based mandibular model and 1-piece of screw-retained metal substructure was produced with the direct metal laser sintering (DMSL) method using Co-Cr compound (n = 10). The distance between the marked points on the multiunit supports and the marginal end of the substructure was measured using a scanning electron microscope (SEM) at each stage (metal, opaque, dentin, and glaze). 15 measurements were taken from each prosthesis, and 150 measurements from 10 samples were obtained. In total, 600 measurements were carried out at 4 stages. One-way ANOVA test was used for statistical evaluation of the data. RESULTS When the obtained marginal range values were examined, differences between groups were found to be statistically significant (P<.001). The lowest values were found in the metal stage (172.4 ± 76.5 µm) and the highest values (238.03 ± 118.92 µm) were determined after glaze application. When the interval values for groups are compared with pairs, the differences between metal with dentin, metal with glaze, opaque with dentin, opaque with glaze, and dentin with glaze were found to be significant (P<.05), whereas the difference between opaque with metal was found to be insignificant (P=.992). CONCLUSION Passive fit of 1-piece designed implant-retained fixed prosthesis that is supported by multiple implants is negatively affected by repetitive firing processes.
Collapse
Affiliation(s)
- Musa Aykut Altintas
- Department of Prosthodontics, Faculty of Dentistry, Cumhuriyet University, Sivas, Turkey
| | - Hakan Akin
- Department of Prosthodontics, Faculty of Dentistry, Sakarya University, Sakarya, Turkey
| |
Collapse
|
34
|
Freifrau von Maltzahn N, Bernhard F, Kohorst P. Fitting accuracy of ceramic veneered Co-Cr crowns produced by different manufacturing processes. J Adv Prosthodont 2020; 12:100-106. [PMID: 32377323 PMCID: PMC7183853 DOI: 10.4047/jap.2020.12.2.100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 12/05/2022] Open
Abstract
PURPOSE The purpose of this in vitro study was to evaluate the fitting accuracy of single crowns made from a novel presintered Co-Cr alloy prepared with a computer-aided design and computer-aided manufacturing (CAD/CAM) technique, as compared with crowns manufactured by other digital and the conventional casting technique. Additionally, the influence of oxide layer on the fitting accuracy of specimens was tested. MATERIALS AND METHODS A total of 40 test specimens made from Co-Cr alloy were investigated according to the fitting accuracy using a replica technique. Four different methods processing different materials were used for the manufacture of the crown copings (milling of presintered (Ceramill Sintron-group_cer_sin) or rigid alloy (Tizian NEM-group_ti_nem), selective laser melting (Ceramill NPL-group_cer_npl), and casting (Girobond NB-group_gir_nb)). The specimens were adapted to a resin model and the outer surfaces were airborne-particle abraded with aluminum oxide. After the veneering process, the fitting accuracy (absolute marginal discrepancy and internal gap) was evaluated by the replica technique in 2 steps, before removing the oxide layer from the intaglio surface of the crowns, and after removing the layer with aluminum oxide airborne-particle abrasion. Statistical analysis was performed by multifactorial analysis of variance (ANOVA) (α=.05). RESULTS Mean absolute marginal discrepancy ranged between 20 µm (group_cer_npl for specimens of Ceramill NPL) and 43 µm (group_cer_sin for crowns of Ceramill Sintron) with the oxide layer and between 19 µm and 28 µm without the oxide layer. The internal gap varied between 33 µm (group_ti_nem for test samples of Tizian NEM) and 75 µm (group_gir_nb for the base material Girobond NB) with the oxide layer and between 30 µm and 76 µm without the oxide layer. The absolute marginal discrepancy and the internal gap were significantly influenced by the fabrication method used (P<.05). CONCLUSION Different manufacturing techniques had a significant influence on the fitting accuracy of single crowns made from Co-Cr alloys. However, all tested crowns showed a clinically acceptable absolute marginal discrepancy and internal gap with and without oxide layer and could be recommended under clinical considerations. Especially, the new system Ceramill Sintron showed acceptable values of fitting accuracy so it can be suggested in routine clinical work.
Collapse
|
35
|
Daou EE, Baba NZ. Evaluation of Marginal and Internal Fit of Presintered Co-Cr and Zirconia Three-Unit Fixed Dental Prosthesis Compared to Cast Co-Cr. J Prosthodont 2020; 29:792-799. [PMID: 32334442 DOI: 10.1111/jopr.13183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 11/30/2022] Open
Abstract
PURPOSE The precision of soft metal processing technologies is poorly documented. This study compared marginal and internal fit of presintered cobalt-chromium (Co-Cr) and zirconia three-unit fixed dental prostheses (FDPs) to cast Co-Cr. MATERIALS AND METHODS Three-unit FDPs were prepared on metal dies (N = 60) from typodont preparations of the maxillary right first premolar and molar. A standardized preparation of a metal-ceramic restoration was done on abutment teeth. The dies (N = 60) were scanned and divided into three groups (n = 20/group) to receive the FDP made of presintered Co-Cr (Ceramill Si), presintered zirconia (Ceramill Zi), and cast Co-Cr (Girobond NB). Each framework was seated on its specific cast. A replica technique was used for marginal and internal discrepancies measurements in mesiodistal and buccolingual planes. Data were analyzed using the Levene test, t-test, and analysis of variance (α = 0.05). RESULTS When the overall mean discrepancy values were compared in the mesiodistal plane, a significant difference was found between Ceramill Sintron and Ceramill Zi groups (p = 0.026). No significant difference was detected between Girobond NB and Ceramill Sintron groups and between Girobond NB and Ceramill Zi groups (p = 0.537 and p = 0.569, respectively). In the buccolingual plane, there was no significant difference in the overall mean discrepancy between the three groups: CS/CZ (p = 1.000), GI/CS (p = 0.51), and GI/CZ (p = 0.87). Significant differences at several measurement points were found at the inter or intramaterial level. The increase in discrepancy values between marginal and occlusal measurements was evident for the three groups. CONCLUSIONS Presintered three-unit FDPs fabricated from zirconia and Co-Cr exhibited internal and marginal discrepancy values similar to cast Co-Cr. A significant difference was reported between CS and CZ in mesiodistal planes. The axial and marginal differences in values for the three tested groups were below or around the 120 µm clinically acceptable threshold except for the occlusal area. When comparing first premolar to first molar, the internal and marginal discrepancies were similar with no apparent distortion of the framework after the sintering process.
Collapse
Affiliation(s)
- Elie E Daou
- Lecturer, Department of Prosthodontics, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon
| | - Nadim Z Baba
- Professor, Advanced Specialty Education Program in Implant Dentistry, School of Dentistry, Loma Linda University, Loma Linda, CA
| |
Collapse
|
36
|
Svanborg P. A systematic review on the accuracy of zirconia crowns and fixed dental prostheses. Biomater Investig Dent 2020; 7:9-15. [PMID: 32010901 PMCID: PMC6968690 DOI: 10.1080/26415275.2019.1708202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 12/17/2019] [Indexed: 11/20/2022] Open
Abstract
Purpose The aim of this study was to review the fit and assess the accuracy of tooth-supported single and multi-unit zirconia fixed dental prostheses. Background The fit of zirconia restorations has been reported in several studies, but the accuracy of the manufacturing process is seldom discussed or used when drawing conclusions on the fit. Materials and methods A literature search of articles published in PubMed between 2 March 2013 and 1 February 2018 was performed using clearly defined inclusion and exclusion criteria. 841 articles were found and 767 were excluded after screening the title and abstract. After full-text analysis another 60 articles were excluded which left 14 articles to be included for data extraction. Fit was the mean of distances reported in the studies and accuracy was the fit minus the pre-set spacer Results For marginal gap of single crowns and multi-unit FDPs combined, the fit was 83 μm and the accuracy was 59 μm. The internal gap fit was 111 μm and the accuracy 61 μm. For the total gap, the fit was 101 μm, and the accuracy of the zirconia restorations was 53 μm. Conclusions Within the limitations of the present systematic review the fit of zirconia single crowns and multi-unit FDPs may be regarded as clinically acceptable, and the accuracy of the manufacturing of zirconia is ∼60 μm for marginal, internal, and total gap. Also, digital impressions seem to be associated with a smaller gap value.
Collapse
Affiliation(s)
- Per Svanborg
- Department of Prosthodontics/Dental Materials Science, Institute of Odontology, The Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden
| |
Collapse
|
37
|
Koulivand S, Ghodsi S, Siadat H, Alikhasi M. A clinical comparison of digital and conventional impression techniques regarding finish line locations and impression time. J ESTHET RESTOR DENT 2019; 32:236-243. [PMID: 31565836 DOI: 10.1111/jerd.12527] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/10/2019] [Accepted: 08/25/2019] [Indexed: 11/28/2022]
Abstract
OBJECTIVE This study compared digital and conventional impression techniques regarding impression time, frequency of adjustments, and adaptation of cobalt-chromium (Co-Cr) copings with supragingival and subgingival finish lines. MATERIALS AND METHODS Thirty premolars prepared for single-unit metal-ceramic restorations with supragingival and subgingival finish lines (n = 15). Conventional impression and digital scan of prepared teeth were made. Using computer aided design/computer aided manufacturing (CAD/CAM) system the copings were produced by a milling machine from Co-Cr blocks and internal and marginal discrepancies were measured using silicone replica technique. Data were analyzed using repeated measures ANOVA and Mann-Whitney test (alpha = .05). RESULTS The impression technique had a significant effect on the magnitude of gap (P < .001). The internal and marginal gaps in the digital technique (49.43 μ and 60.07 μ, respectively) were significantly lower than the values in the conventional method (91.88 μ and 96.96 μ, respectively-P < .001). Finish line positions had no significant effect on the fit and marginal gap of copings (P = .54 and .243, respectively). The mean impression time (19':27″ in conventional technique and 10':31″ in digital technique) was significantly shorter (P < .001) and the mean frequency of adjustments (2.2 times for conventional and 1.3 times for digital technique) was significantly lower in the digital technique (P < .001). The gingival biotype (thick or thin) had no significant effect on marginal and internal fit (P = .052 and .319, respectively). CONCLUSION The digital technique was superior in terms of fit, impression time, and frequency of adjustments. Finish line positions had no significant effect on the fit of copings. CLINICAL SIGNIFICANCE Using intraoral scanner promotes the fits of restorations in supragingival and subgingival finish lines.
Collapse
Affiliation(s)
- Soudabeh Koulivand
- Prosthodontic Department, Dentistry School, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Safoura Ghodsi
- Prosthodontic Department, Dentistry School, Tehran University of Medical Science, Tehran, Iran
| | - Hakimeh Siadat
- Prosthodontic Department, Dentistry School, Tehran University of Medical Science, Tehran, Iran
| | - Marzieh Alikhasi
- Prosthodontic Department, Dentistry School, Tehran University of Medical Science, Tehran, Iran
| |
Collapse
|
38
|
Alikhasi M, Rohanian A, Ghodsi S, Kolde AM. Digital versus conventional techniques for pattern fabrication of implant-supported frameworks. Eur J Dent 2019; 12:71-76. [PMID: 29657528 PMCID: PMC5883480 DOI: 10.4103/ejd.ejd_314_17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Objective The aim of this experimental study was to compare retention of frameworks cast from wax patterns fabricated by three different methods. Materials and Methods Thirty-six implant analogs connected to one-piece abutments were divided randomly into three groups according to the wax pattern fabrication method (n = 12). Computer-aided design/computer-aided manufacturing (CAD/CAM) milling machine, three-dimensional printer, and conventional technique were used for fabrication of waxing patterns. All laboratory procedures were performed by an expert-reliable technician to eliminate intra-operator bias. The wax patterns were cast, finished, and seated on related abutment analogs. The number of adjustment times was recorded and analyzed by Kruskal-Wallis test. Frameworks were cemented on the corresponding analogs with zinc phosphate cement and tensile resistance test was used to measure retention value. Statistical Analysis Used One-way analysis of variance (ANOVA) and post hoc Tukey tests were used for statistical analysis. Level of significance was set at P < 0.05. Results The mean retentive values of 680.36 ± 21.93 N, 440.48 ± 85.98 N, and 407.23 ± 67.48 N were recorded for CAD/CAM, rapid prototyping, and conventional group, respectively. One-way ANOVA test revealed significant differences among the three groups (P < 0.001). The post hoc Tukey test showed significantly higher retention for CAD/CAM group (P < 0.001), while there was no significant difference between the two other groups (P = 0.54). CAD/CAM group required significantly more adjustments (P < 0.001). Conclusions CAD/CAM-fabricated wax patterns showed significantly higher retention for implant-supported cement-retained frameworks; this could be a valuable help when there are limitations in the retention of single-unit implant restorations.
Collapse
Affiliation(s)
- Marzieh Alikhasi
- Dental Research Center, Dentistry Research Institute and Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Ahmad Rohanian
- Dental Research Center, Dentistry Research Institute and Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Safoura Ghodsi
- Dental Research Center, Dentistry Research Institute and Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| | - Amin Mohammadpour Kolde
- Dental Student Research Center, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
39
|
Comparison of Overall Fit of Milled and Laser-Sintered CAD/CAM Crown Copings. Int J Dent 2019; 2019:7310175. [PMID: 31360167 PMCID: PMC6642757 DOI: 10.1155/2019/7310175] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 06/26/2019] [Indexed: 11/29/2022] Open
Abstract
Background and Aims The aim of this study was to investigate the effect of computer-aided design/computer-aided manufacturing (CAD/CAM) procedures on the overall fit of metal copings. Materials and Methods A standardized die was made in die stone of an upper right molar prepared for a full crown. The die was digitalized by an Identica Blue Light Scanner, and the coping substructure was designed using CAD software. Ten milled specimens and ten laser-sintered specimens were manufactured by Renishaw plc based on the generated file by the software. All twenty copings were digitized by the Identica scanner, and the data were superimposed with the original premanufacturing data file of the prepared full crown. Using the Geometric Modelling Library (GML) package, the fit discrepancies were displayed as colour maps showing discrepancies in three dimensions. Each map was made up of thousands of data points carrying numerical error values allowing detailed analyses. Results The milled group displayed a mean of fit discrepancies of 42.20 μm (SD 3.04 μm), while the laser-sintered group showed a mean of 42.24 μm fit discrepancies (SD 2.94 μm). Thus, a small difference of 0.04 μm between the two groups was detected. Conclusions The evaluated manufacturing systems can be used in dental practice as a small and insignificant discrepancy of fit between the two manufacturing methods was detected.
Collapse
|
40
|
Migita S, Sakashita K, Suyalatu. Osteoblast compatibility of 3D printed Co–Cr–Mo alloys with different building direction. BIOSURFACE AND BIOTRIBOLOGY 2019. [DOI: 10.1049/bsbt.2018.0043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Satoshi Migita
- Graduate School of Science and EngineeringYamagata University4‐3‐16 Jonan, YonezawaYamagataJapan
| | - Kosuke Sakashita
- Graduate School of Science and EngineeringYamagata University4‐3‐16 Jonan, YonezawaYamagataJapan
| | - Suyalatu
- NTT Data Engineering Systems Corporation AM Design Lab2‐6‐58 Senbahigashi, MinooOsakaJapan
| |
Collapse
|
41
|
Al Maaz A, Thompson GA, Drago C, An H, Berzins D. Effect of finish line design and metal alloy on the marginal and internal gaps of selective laser melting printed copings. J Prosthet Dent 2019; 122:143-151. [PMID: 30948295 DOI: 10.1016/j.prosdent.2019.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 02/07/2019] [Accepted: 02/07/2019] [Indexed: 10/27/2022]
Abstract
STATEMENT OF PROBLEM Selective laser melting (SLM) technology has been introduced for printing metal dental restorations from Co-Cr base alloys or Au-Pt high noble alloys. However, information regarding the fit of restorations fabricated by using this technique is limited. PURPOSE The purpose of this in vitro study was to determine the effect of 3 different finish line designs on the marginal and internal gaps of metal copings made from a base (Co-Cr), high noble (Au-Pd-Ag), and noble alloy (Co-Pd) by using the SLM technology. MATERIAL AND METHODS Three Ivorine right maxillary central incisors were prepared with a chamfer, deep chamfer, or shoulder finish line. The preparations were scanned by using a TRIOS scanner, and a total of 90 dies were printed using DPR 10 Resin (30×3 finish line designs). Ten SLM copings were fabricated for each margin design and metal alloy combination for a total of 90 copings (10×3 finish line designs×3 alloys). Copings were cemented onto dies using an autopolymerizing composite-resin luting material. All coping-die assemblies were sectioned buccolingually by using a low-speed diamond saw, and images were obtained by using an inverted bright field metallurgical microscope at ×100 magnification. Marginal and internal gaps were measured at 5 locations: buccal margin, midfacial, incisal, midlingual, and lingual margin. After gap measurements, representative specimens were embedded in autopolymerizing resin and prepared for metallographic examination. A 2-way multivariate analysis of variance (MANOVA) was conducted to determine the overall significance, followed by ANOVA for each dependent variable (α=.05). RESULTS The results indicated that alloy type and finish line had a significant influence on marginal gap of copings (P<.001). Relative to the internal gap, alloy type had a significant effect (P<.001), but the type of finish line had no statistically significant influence (P=.337). No statistically significant interactions occurred. Base alloys were printed with almost no observable porosity, whereas noble and high noble alloys exhibited hot tears and porosity. CONCLUSIONS Thefinish line type did not influence the internal gap between copings and dies, whereas the alloy type influenced the marginal gap between copings and dies. SLM-fabricated Co-Cr copings on teeth prepared with a deep chamfer finish line demonstrated the lowest marginal gap.
Collapse
Affiliation(s)
- Adel Al Maaz
- Resident, Graduate Prosthodontics, Marquette University School of Dentistry, Milwaukee, Wis
| | - Geoffrey A Thompson
- Associate Professor and Director, Graduate Prosthodontics, Marquette University School of Dentistry, Milwaukee, Wis.
| | - Carl Drago
- Assistant Professor, Graduate Prosthodontics, Marquette University School of Dentistry, Milwaukee, Wis
| | - Hongseok An
- Assistant Professor, Department of General Dental Sciences, Marquette University School of Dentistry, Milwaukee, Wis
| | - David Berzins
- Professor and Director, Graduate Dental Biomaterials, Department of General Dental Sciences, Marquette University School of Dentistry, Milwaukee, Wis
| |
Collapse
|
42
|
Izadi A, Vafaee F, Shishehian A, Roshanaei G, Fathi Afkari B. Evaluation of dimensional accuracy of dental bridges manufactured with conventional casting technique and CAD/CAM system with Ceramill Sintron blocks using CMM. J Dent Res Dent Clin Dent Prospects 2019; 12:264-271. [PMID: 30774792 PMCID: PMC6368946 DOI: 10.15171/joddd.2018.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 11/19/2018] [Indexed: 11/09/2022] Open
Abstract
Background. Recently, non-presintered chromium-cobalt (Cr-Co) blocks with the commercial name of Ceramill Sintron were introduced to the market. However, comprehensive studies on the dimensional accuracy and fit of multi-unit frameworks made of these blocks using the coordinate measuring machine (CMM) are lacking. This study aimed to assess and compare the dimensional changes and fit of conventional casting and milled frameworks using Ceramill Sintron.
Methods. A metal model was designed and scanned and 5-unit frameworks were fabricated using two techniques: (I) the conventional casting method (n=20): the wax model was designed, milled in the CAD/CAM machine, flasked and invested; (II) the milling method using Ceramill Sintron blocks (n=20): the wax patterns of group 1 were used; Ceramill Sintron blocks were milled and sintered. Measurements were made on the original reference model and the fabricated frameworks using the CMM in all the three spatial dimensions, and dimensional changes were recorded in a checklist. Data were analyzed with descriptive statistics, and the two groups were compared using one-way ANOVA and Tukey test (α=0.05).
Results. The fabricated frameworks in both groups showed significant dimensional changes in all the three dimensions. Comparison of dimensional changes between the two groups revealed no significant differences (P>0.05) except for transverse changes (arch) that were significantly greater in Ceramill Sintron frameworks (P<0.05).
Conclusion. The two manufacturing processes were the same regarding dimensional changes and the magnitude of marginal gaps and both processes resulted in significant dimensional changes in frameworks. Ceramill Sintron frameworks showed significantly greater transverse changes than the conventional frameworks.
Collapse
Affiliation(s)
- Alireza Izadi
- Department of Prosthodontic Dentistry, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Fariborz Vafaee
- Implant Research Center, Department of Prosthodontics, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Arash Shishehian
- Department of Prosthodontic Dentistry, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Ghodratollah Roshanaei
- Modeling of Noncommunicable Diseases Research Center, Department of Biostatistics and Epidemiology, Faculty of Public Health, Hamadan University
| | - Behzad Fathi Afkari
- Department of Prosthodontic Dentistry, Faculty of Dentistry, Hamadan University of Medical Sciences, Hamadan, Iran
| |
Collapse
|
43
|
Yildirim B, Paken G. Evaluation of the Marginal and Internal Fit of Implant-Supported Metal Copings Fabricated with 3 Different Techniques: An In Vitro Study. J Prosthodont 2019; 28:315-320. [PMID: 30667169 DOI: 10.1111/jopr.13022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2019] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To compare the marginal and internal fit of cobalt-chromium (Co-Cr) alloy copings fabricated by with lost wax technique (LW), computer-aided design and computer-aided manufacturing (CAD/CAM), and direct metal laser sintering (DMLS). MATERIALS AND METHODS Thirty-six tissue level, straight titanium abutments were screwed onto implant replicas. All specimens were embedded in acrylic resin and randomly divided into 3 subgroups according to the fabrication of metal coping: LW, CAD/CAM, and DMLS. In total, 36 (n = 12/group) Co-Cr implant-supported metal copings were prepared. Marginal, intermarginal, axial, and occlusal fits of each coping were measured using the silicone replica technique. The data were evaluated statistically using one-way ANOVA and Bonferioni post-hoc test (α = 0.05). RESULTS The CAD/CAM group showed significantly lower marginal fit than the LW group and DMLS groups (p < 0.001). The marginal fit of the LW group was not significantly different from the DMLS group (p = 0.721). No significant difference found among the fabrication methods in terms of intermarginal fit (p = 0.913). The CAD/CAM group showed lower axial fit than the LW group (p = 0.026), but there was no statistical difference between the DMLS group and the LW (p = 0.999) and CAD/CAM groups (p = 0.247). No significant differences found among the fabrication methods in terms of occlusal fit (p = 0.158). CONCLUSIONS The LW and DMLS groups showed better marginal fit compared to the CAD/CAM group; however, the CAD/CAM group was better than the LW group in terms of axial fit. All fabrication methods demonstrated similar intermarginal and occlusal fit.
Collapse
Affiliation(s)
- Bengisu Yildirim
- Department of Prosthodontics, Faculty of Dentistry, Usak University, Usak, Turkey
| | - Gamze Paken
- Department of Prosthodontics, Faculty of Dentistry, Usak University, Usak, Turkey
| |
Collapse
|
44
|
Pilo R, Agar-Zoizner S, Gelbard S, Levartovsky S. The Retentive Strength of Laser-Sintered Cobalt-Chromium-Based Crowns after Pretreatment with a Desensitizing Paste Containing 8% Arginine and Calcium Carbonate. Int J Mol Sci 2018; 19:ijms19124082. [PMID: 30562955 PMCID: PMC6321158 DOI: 10.3390/ijms19124082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 12/01/2018] [Accepted: 12/13/2018] [Indexed: 11/16/2022] Open
Abstract
The retention of laser-sintered cobalt-chromium (Co-Cr)-based crowns were examined after dentin pretreatment with desensitizing paste containing 8% arginine and calcium carbonate (DP-ACC). Forty lower first molars were prepared using a standardized protocol. The Co-Cr crowns were produced using selective laser melting. The teeth were either pretreated with the desensitizing paste or not pretreated. After one week, each group was cemented with glass ionomer cement (GIC) or zinc phosphate cement (ZPC). Surface areas of the teeth were measured before cementation. After aging, a universal testing machine was used to test the retentive strength of the cemented crown-tooth assemblies. The debonded surfaces of the teeth and crowns were examined at 2.7× magnification. Pretreating the dentin surfaces with the desensitizing paste before cementation with GIC or ZPC did not affect the retention of the Co-Cr crowns. The retention of the GIC group (6.04 ± 1.10 MPa) was significantly higher than that of the ZPC group (2.75 ± 1.25 MPa). The predominant failure mode for the ZPC and the nontreated GIC group was adhesive cement-dentin failure; for the treated GIC group, it was adhesive cement-crown failure. The desensitizing paste can be safely used to reduce post-cementation sensitivity without reducing the retentive strength of Co-Cr crowns cemented with GIC or ZPC.
Collapse
Affiliation(s)
- Raphael Pilo
- Department of Oral Rehabilitation, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel- Aviv University, Tel -Aviv 6997801, Israel.
| | - Sharon Agar-Zoizner
- Department of Oral Rehabilitation, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel- Aviv University, Tel -Aviv 6997801, Israel.
| | - Shaul Gelbard
- Department of Oral Rehabilitation, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel- Aviv University, Tel -Aviv 6997801, Israel.
| | - Shifra Levartovsky
- Department of Oral Rehabilitation, The Maurice and Gabriela Goldschleger School of Dental Medicine, Tel- Aviv University, Tel -Aviv 6997801, Israel.
| |
Collapse
|
45
|
Akçin ET, Güncü MB, Aktaş G, Aslan Y. Effect of manufacturing techniques on the marginal and internal fit of cobalt-chromium implant-supported multiunit frameworks. J Prosthet Dent 2018; 120:715-720. [DOI: 10.1016/j.prosdent.2018.02.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 02/19/2018] [Accepted: 02/19/2018] [Indexed: 11/24/2022]
|
46
|
Evaluation of the fit of metal copings fabricated using stereolithography. J Prosthet Dent 2018; 120:693-698. [DOI: 10.1016/j.prosdent.2018.01.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 01/19/2018] [Accepted: 01/19/2018] [Indexed: 11/18/2022]
|
47
|
Influence of repeated firings on marginal, axial, axio-occlusal, and occlusal fit of metal-ceramic restorations fabricated with different techniques. J Prosthet Dent 2018; 120:415-420. [DOI: 10.1016/j.prosdent.2017.11.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/22/2017] [Accepted: 11/22/2017] [Indexed: 01/04/2023]
|
48
|
Internal adaptation of cobalt-chromium posts fabricated by selective laser melting technology. J Prosthet Dent 2018; 121:455-460. [PMID: 30126687 DOI: 10.1016/j.prosdent.2018.03.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 03/07/2018] [Accepted: 03/08/2018] [Indexed: 11/24/2022]
Abstract
STATEMENT OF PROBLEM Selective laser melting (SLM) has become popular in prosthetic dentistry. However, only limited information is available for the internal adaptation of cobalt-chromium (Co-Cr) posts fabricated by SLM. PURPOSE The purpose of this in vitro study was to investigate the internal adaptation of Co-Cr metal posts fabricated by SLM technique. MATERIAL AND METHODS Thirty-six Co-Cr metal posts were fabricated by conventional casting, subtractive computer-aided design and computer-aided manufacturing (CAD-CAM), and additive CAD-CAM, by making an impression from a standardized model of a tooth with a single root canal. Posts and the dies were bonded with cement. Specimens were then sectioned horizontally by using a grinding and polishing machine, and 3 different cross-sections of each post were chosen to represent the apical, middle, and coronal regions. The areas of cement were photographed by using a stereomicroscope at an original magnification of ×32 and measured using image-measuring software. From each group, 1 specimen was randomly selected and observed by using scanning electron microscopy. One-way ANOVA and Tukey honestly significant difference test were performed to identify differences among groups with regard to internal adaptation (α=.05). RESULT The internal adaptation of the SLM group did not differ from that of the CAD-CAM milling group at 3 cross-section levels (P>.05). At the apical and coronal cross-section levels, the cement area of SLM group was smaller than that of the cast group (P<.05). However, at the middle cross-section level, the cement area of the cast group was significantly smaller than that of the SLM group (P<.05). Use of scanning electron microscopy showed both the SLM group and the CAD-CAM milling group exhibited homogeneous microstructures. However, the cast group showed a typical discontinuous dendritic solidification microstructure. CONCLUSIONS The internal adaptation of SLM was not inferior to that of the CAD-CAM milling group or the cast group. The SLM technique seems a promising choice for fabricating dental posts.
Collapse
|
49
|
Daou EE, Ounsi H, Özcan M, Al-Haj Husain N, Salameh Z. Marginal and internal fit of pre-sintered Co-Cr and zirconia 3-unit fixed dental prostheses as measured using microcomputed tomography. J Prosthet Dent 2018; 120:409-414. [PMID: 29724558 DOI: 10.1016/j.prosdent.2018.01.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 01/09/2018] [Accepted: 01/09/2018] [Indexed: 10/17/2022]
Abstract
STATEMENT OF PROBLEM Limited information is available on the precision of new metal processing technologies. PURPOSE The purpose of this in vitro study was to evaluate the marginal and internal fit of pre-sintered cobalt-chromium (Co-Cr) and zirconia 3-unit fixed dental prostheses using x-ray microcomputed tomography. MATERIAL AND METHODS Three-unit fixed dental prostheses were prepared on metal dies (N=12) using a typodont model from the maxillary first premolar to the first molar. A standardized preparation with a 1.2-mm chamfer (360 degrees) and a 2-mm occlusal reduction was prepared on abutment teeth. The dies were scanned and divided into 2 groups to receive the fixed dental prostheses (n=6) made of pre-sintered Co-Cr and pre-sintered zirconia. Each framework was seated on its cast, and marginal and internal discrepancies were measured at 9 points, starting from the most distal point from the pontic for the maxillary first premolar and the first molar (points 1-4, mesial; point 5, occlusal; points 6-9, distal) of each abutment tooth using microcomputed tomography. The data were analyzed using the Levene test, t test, and ANOVA (α=.05). RESULTS When overall mean discrepancy values were compared, no significant difference was observed between pre-sintered Co-Cr and pre-sintered zirconia (P=.085). Discrepancy values for points 1, 2, and 3 were significantly different for pre-sintered Co-Cr and pre-sintered zirconia, with the lowest mean values for point 1 and the highest for point 5. On the abutment tooth basis, for the maxillary first premolar and the first molar, a significant difference was found only in points 6 (P<.001) and 8 (P<.003) for both materials. When the discrepancies for the maxillary first premolar were considered for pre-sintered Co-Cr and pre-sintered zirconia, the mean values were significantly different only at points 1 (P<.001), 2 (P=.007), and 3 (P=.003) and were smaller for pre-sintered zirconia. For the tooth the first molar, a significant difference was observed at point 2 (P=.002) and point 3 (P=.008) for both materials, where the mean values were higher for pre-sintered Co-Cr than for pre-sintered zirconia. The pairwise comparison between points showed a significant difference between measurement points within each material (P<.05). The increase in values between points 1 and 5 was evident for both pre-sintered Co-Cr and pre-sintered zirconia materials. CONCLUSIONS Three-unit fixed dental prostheses made of pre-sintered Co-Cr or zirconia showed similar marginal and internal discrepancy values, with the highest discrepancy values at the occlusal region in both the first premolar and first molar.
Collapse
Affiliation(s)
- Elie E Daou
- Doctorate student, Department of Prosthodontics, Faculty of Dentistry, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon.
| | - Hani Ounsi
- Professor, Department of Prosthodontics, Faculty of Dentistry, Faculty of Dental Medicine, Lebanese University, Beirut, Lebanon
| | - Mutlu Özcan
- Professor, University of Zurich, Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Zurich, Switzerland
| | - Nadin Al-Haj Husain
- Dentist, University of Zurich, Dental Materials Unit, Center for Dental and Oral Medicine, Clinic for Fixed and Removable Prosthodontics and Dental Materials Science, Zurich, Switzerland
| | - Ziad Salameh
- Professor, Department of Research, Department of Prosthodontics, Faculty of Dentistry, Faculty of Dental Medicine, Beirut, Lebanon
| |
Collapse
|
50
|
Arnold C, Hey J, Schweyen R, Setz JM. Accuracy of CAD-CAM-fabricated removable partial dentures. J Prosthet Dent 2018; 119:586-592. [DOI: 10.1016/j.prosdent.2017.04.017] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 04/18/2017] [Accepted: 04/18/2017] [Indexed: 10/19/2022]
|