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Albergaria LS, Scotti CK, Mondelli RFL, Vega HA, Faggion CM, Bombonatti JFS, Velo MMDAC. Effect of nanofibers as reinforcement on resin-based dental materials: A systematic review of in vitro studies. JAPANESE DENTAL SCIENCE REVIEW 2023; 59:239-252. [PMID: 37593731 PMCID: PMC10429726 DOI: 10.1016/j.jdsr.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 04/16/2023] [Accepted: 07/12/2023] [Indexed: 08/19/2023] Open
Abstract
This systematic review provides an update on the effect of nanofibers as reinforcement on resin-based dental materials. A bibliographic search was conducted in MEDLINEPubMed, Embase, Web of Science, Scopus, BVS (LILACS, BBO e IBECS), Cochrane, LIVIVO, and gray literature (BDTD) to identify relevant articles up to May 2021. In vitro studies that evaluated and compared the mechanical properties of nanofibers resin-based composite materials, were eligible. No publication year or language restriction was applied, and methodological quality was assessed using two methods. In a total of 6100 potentially eligible studies, 81 were selected for full-text analysis and 35 were included for qualitative analysis. Of the 35 included studies, a total of 29 studies evaluated the flexural strength (FS) of the materials. These groups were distinguished according to the resin-based materials tested and nanofiber types. Most of the studies evaluated materials composed of glass fibers and demonstrated higher values of FS when compared to resin-based materials without nanofibers. The incorporation of nanofibers into resin-based dental materials improved the mechanical properties compared to resin-based materials without nanofibers, suggesting better performance of these materials in high-stressbearing application areas. Further clinical studies are required to confirm the efficacy of resin-based materials with nanofibers.
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Affiliation(s)
- Laís Santos Albergaria
- Department of Operative Dentistry, Endodontics, and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Cassiana Koch Scotti
- Department of Operative Dentistry, Endodontics, and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Rafael Francisco Lia Mondelli
- Department of Operative Dentistry, Endodontics, and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Heber Arbildo Vega
- Faculty of Dentistry, Department of General Dentistry, San Martín de Porres University, Chiclayo, Peru
- Faculty of Human Medicine, Department of Human Medicine, San Martín de Porres University, Chiclayo, Peru
| | - Clovis Mariano Faggion
- Department of Periodontology and Operative Dentistry, Faculty of Dentistry, University Hospital Münster, Münster, Germany
| | - Juliana Fraga Soares Bombonatti
- Department of Operative Dentistry, Endodontics, and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
| | - Marilia Mattar de Amoêdo Campos Velo
- Department of Operative Dentistry, Endodontics, and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, São Paulo, Brazil
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Zhang X, Zhang Y, Li Y, Wang X, Zhang X. Restorative Dental Resin Functionalized with Calcium Methacrylate with a Hydroxyapatite Remineralization Capacity. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6497. [PMID: 37834635 PMCID: PMC10573481 DOI: 10.3390/ma16196497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/24/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023]
Abstract
The ability of dental materials to induce the mineralization of enamel like hydroxyapatite (HA) is of great importance. In this article, a novel kind of dental restorative material characterized by a mineralization ability was fabricated by photopolymerization. Calcium methacrylate (CMA) was introduced into the classical bisphenol A-glycidyl methacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) dental resin formulation. This functional dental resin (BTCM) was calcium-rich and can be prepared simply by one-step photopolymerization. The influence of CMA on the photopolymerization kinetics, the dental resin's mechanical properties, and its capacity to induce dynamic in situ HA mineralization were examined. Real-time FTIR, compression modulus, scanning electron microscopy, X-ray spectroscopy, MTT assay, and cell attachment test were carried out. The obtained data were analyzed for statistical significance using analysis of variance (ANOVA). Double bond conversion could be completed in less than 300 s, while the compression modulus of BTCM decreased with the increase in CMA content (30 wt%, 40 wt%, and 50 wt%). After being soaked in Ca(NO3)2 and Na2HPO4 solutions alternatively, dense HA crystals were found on the surface of the dental resin which contained CMA. The amount of HA increased with the increase in CMA content. The MTT results indicated that BTCM possesses good biocompatibility, while the cell adhesion and proliferation investigation demonstrated that L929 cells can adhere and proliferate well on the surface of BTM. Thus, our approach provides a straightforward, cost-effective, and environmentally friendly solution that has the potential for immediate clinical use.
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Affiliation(s)
- Xin Zhang
- College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, China
| | - Yuxuan Zhang
- FuYang Sineva Materials Technology Co., Ltd., Beijing 100176, China;
| | - Ying Li
- College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, China
| | - Xiaoming Wang
- Shuozhou Comprehensive Inspection and Testing Center, Shuozhou 036000, China
| | - Xueqin Zhang
- College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, China
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Torkian P, Mortazavi Najafabadi S, Ghashang M, Grzelczyk D. Glass-Ceramic Fillers Based on Zinc Oxide-Silica Systems for Dental Composite Resins: Effect on Mechanical Properties. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6268. [PMID: 37763546 PMCID: PMC10533065 DOI: 10.3390/ma16186268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/11/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023]
Abstract
The potential of glass ceramics as applicable materials in various fields including fillers for dental restorations is our guide to present a new procedure for improvements of the mechanical properties of dental composites. This work aims to use Zn2SiO4 and SiO2-ZnO nano-materials as fillers to improve the mechanical properties of Bis-GMA/TEGDMA mixed dental resins. Zn2SiO4 and SiO2-ZnO samples were prepared and characterized by using XRD, FE-SEM, EDX, and FT-IR techniques. The XRD pattern of the SiO2-ZnO sample shows that ZnO crystallized in a hexagonal phase, while the SiO2 phase was amorphous. Similarly, the Zn2SiO4 sample crystallized in a rhombohedral crystal system. The prepared samples were used as fillers for the improvement of the mechanical properties of Bis-GMA/TEGDMA mixed dental resins. Five samples of dental composites composed of Bis-GMA/TEGDMA mixed resins were filled with 2, 5, 8, 10, and 15 wt% of SiO2-ZnO, and similarly, five samples were filled with Zn2SiO4 samples (2, 5, 8, 10, and 15 wt%). All of the 10 samples (A1-A10) were characterized by using different techniques including FT-IR, FE-SEM, EDX, and TGA analyses. According to the TGA analysis, all samples were thermally stable up to 200 °C, and the thermal stability increased with the filler percent. Next, the mechanical properties of the samples including the flexural strength (FS), flexural modulus (FM), diameter tensile strength (DTS), and compressive strength (CS) were investigated. The obtained results revealed that the samples filled with 8 wt% of SiO2-ZnO and 10 wt% of Zn2SiO4 had higher FS values of 123.4 and 136.6 MPa, respectively. Moreover, 8 wt% of both fillers displayed higher values of the FM, DTS, and CS parameters. These values were 8.6 GPa, 34.2 MPa, and 183.8 MPa for SiO2-ZnO and 11.3 GPa, 41.2 MPa, and 190.5 MPa for the Zn2SiO4 filler. Inexpensive silica-based materials enhance polymeric mechanics. Silica-metal oxide nanocomposites improve dental composite properties effectively.
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Affiliation(s)
- Peyman Torkian
- Department of Manufacturing, Faculty of Mechanical Engineering, Babol Noshirvani University of Technology, Babol 47148-71167, Iran
| | - SayedMohsen Mortazavi Najafabadi
- Department of Automation, Biomechanics and Mechatronics, Lodz University of Technology, 1/15 Stefanowski Street, 90-537 Lodz, Poland
| | - Majid Ghashang
- Department of Chemistry, Najafabad Branch, Islamic Azad University, Najafabad 15847-43311, Iran
| | - Dariusz Grzelczyk
- Department of Automation, Biomechanics and Mechatronics, Lodz University of Technology, 1/15 Stefanowski Street, 90-537 Lodz, Poland
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Velo MMDAC, Nascimento TRDL, Obeid AT, Brondino NCM, Mondelli RFL. Evaluation of contact angle and mechanical properties of resin monomers filled with graphene oxide nanofibers. Braz Dent J 2023; 34:127-134. [PMID: 37909635 PMCID: PMC10642268 DOI: 10.1590/0103-6440202305299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 07/24/2023] [Indexed: 11/03/2023] Open
Abstract
This in vitro study synthesized hybrid nanofibers embedded in graphene oxide (GO) and incorporated them into experimental resin composite monomers to evaluate their physical-mechanical properties. Inorganic-organic hybrid nanofibers were produced with precursor solutions of 1% wt. GO-filled Poly (d,l-lactide, PLA) fibers and scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) characterized the morphology and chemical composition of the spun fibers. Resin composite monomers were developed and a total of 5% nanofibers were incorporated into the experimental materials. Three groups were developed: G1 (control resin monomers), G2 (resin monomers/PLA nanofibers), and G3 (resin monomers/inorganic-organic hybrid nanofibers). Contact angle (n=3), flexural strength (n=22), elastic modulus (n=22), and Knoop hardness (n=6) were evaluated. The mean of the three indentations was obtained for each sample. The normality of data was assessed by QQ Plot with simulated envelopes and analyzed by Welch's method (p<0.05). Overall, SEM images showed the regular shape of nanofibers but were non-aligned. Compositional analysis from EDS (n=6) revealed the presence of carbon and oxygen (present in GO composition) and Si from the functionalization process. The results of contact angle (°) and hardness (Kg/mm2) for each group were as follow, respectively: G1 (59.65±2.90; 37.48±1.86a), G2 (67.99±3.93; 50.56±1.03b) and G3 (62.52±7.40; 67.83±1.01c). The group G3 showed the highest Knoop hardness values (67.83 kg/mm2), and the flexural strength of all groups was adversely affected. The experimental resin composite composed of hybrid nanofibers with GO presented increased hardness values and hydrophilic behavior.
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Affiliation(s)
- Marilia Mattar de Amoêdo Campos Velo
- Department of Chemistry, Research and Extension Center for Fuels and Materials Laboratory (NPELACOM), Federal University of Paraiba, João Pessoa, Paraíba, Brazil
| | | | - Alyssa Teixeira Obeid
- Department of Chemistry, Research and Extension Center for Fuels and Materials Laboratory (NPELACOM), Federal University of Paraiba, João Pessoa, Paraíba, Brazil
| | | | - Rafael Francisco Lia Mondelli
- Department of Chemistry, Research and Extension Center for Fuels and Materials Laboratory (NPELACOM), Federal University of Paraiba, João Pessoa, Paraíba, Brazil
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Alrahlah A, Khan R, Al-Odayni AB, Saeed WS, Bautista LS, Haider S, De Vera MAT, Alshabib A. Fabrication of Novel Pre-Polymerized BisGMA/Silica Nanocomposites: Physio-Mechanical Considerations. J Funct Biomater 2023; 14:323. [PMID: 37367287 DOI: 10.3390/jfb14060323] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/11/2023] [Accepted: 06/15/2023] [Indexed: 06/28/2023] Open
Abstract
Resin composite mimics tooth tissues both in structure and properties, and thus, they can withstand high biting force and the harsh environmental conditions of the mouth. Various inorganic nano- and micro-fillers are commonly used to enhance these composites' properties. In this study, we adopted a novel approach by using pre-polymerized bisphenol A-glycidyl methacrylate (BisGMA) ground particles (XL-BisGMA) as fillers in a BisGMA/triethylene glycol dimethacrylate (TEGDMA) resin system in combination with SiO2 nanoparticles. The BisGMA/TEGDMA/SiO2 mixture was filled with various concentrations of XL-BisGMA (0, 2.5, 5, and 10 wt.%). The XL-BisGMA added composites were evaluated for viscosity, degree of conversion (DC), microhardness, and thermal properties. The results demonstrated that the addition of a lower concentration of XL-BisGMA particles (2.5 wt.%) significantly reduced (p ≤ 0.05) the complex viscosity from 374.6 (Pa·s) to 170.84. (Pa·s). Similarly, DC was also increased significantly (p ≤ 0.05) by the addition of 2.5 wt.% XL-BisGMA, with the pristine composite showing a DC of (62.19 ± 3.2%) increased to (69.10 ± 3.4%). Moreover, the decomposition temperature has been increased from 410 °C for the pristine composite (BT-SB0) to 450 °C for the composite with 10 wt.% of XL-BisGMA (BT-SB10). The microhardness has also been significantly reduced (p ≤ 0.05) from 47.44 HV for the pristine composite (BT-SB0) to 29.91 HV for the composite with 2.5 wt.% of XL-BisGMA (BT-SB2.5). These results suggest that a XL-BisGMA could be used to a certain percentage as a promising filler in combination with inorganic fillers to enhance the DC and flow properties of the corresponding resin-based dental composites.
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Affiliation(s)
- Ali Alrahlah
- Restorative Dental Sciences Department, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | - Rawaiz Khan
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | - Abdel-Basit Al-Odayni
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | - Waseem Sharaf Saeed
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | - Leonel S Bautista
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
| | - Sajjad Haider
- Department of Chemical Engineering, College of Engineering, King Saud University, Riyadh 11421, Saudi Arabia
| | | | - Abdulrahman Alshabib
- Restorative Dental Sciences Department, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
- Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia
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De Angelis F, Vadini M, Buonvivere M, Valerio A, Di Cosola M, Piattelli A, Biferi V, D’Arcangelo C. In Vitro Mechanical Properties of a Novel Graphene-Reinforced PMMA-Based Dental Restorative Material. Polymers (Basel) 2023; 15:polym15030622. [PMID: 36771922 PMCID: PMC9919729 DOI: 10.3390/polym15030622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 01/15/2023] [Accepted: 01/20/2023] [Indexed: 01/27/2023] Open
Abstract
Recent studies suggest that the incorporation of graphene in resin-based dental materials might enhance their mechanical properties and even decrease their degree of contraction during polymerization. The present study aimed at comparing the three-point flexural strength (FS), the compressive strength (CS), and the Vickers hardness (VH) of a CAD/CAM poly-methylmethacrylate (PMMA)-based resin, a recently introduced graphene-reinforced CAD/CAM PMMA-based resin (G-PMMA), and a conventional dental bis-acryl composite resin (BACR). No significant differences (p > 0.05) were detected among the materials in terms of flexural strength. On the other hand, a mean flexural modulus value of 9920.1 MPa was recorded in BACR group, significantly higher compared to the flexural modulus detected for G-PMMA (2670.2 MPa) and for conventional PMMA (2505.3) (p < 0.05). In terms of compressive modulus (MPa) and compressive strength (MPa), BACR was significantly stiffer than PMMA and G-PMMA. Concerning VH measurements, a significantly increased hardness emerged comparing the BACR group (VH 98.19) to both PMMA and G-PMMA groups (VH 34.16 and 34.26, respectively). Based on the finding of the present study, the graphene-reinforced (PMMA)-based polymer herein tested was not superior to the conventional PMMA and seemed not able to be considered as an alternative material for permanent restorations, at least in terms of hardness and mechanical response to compressive stress. More research on the mechanical/biological properties of G-PMMAs (and on graphene as a filler) seems still necessary to better clarify their potential as dental restorative materials.
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Affiliation(s)
- Francesco De Angelis
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, University of Chieti, 66100 Chieti, Italy
- Correspondence: ; Tel.: +39-(0)85-4549652
| | - Mirco Vadini
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, University of Chieti, 66100 Chieti, Italy
| | - Matteo Buonvivere
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, University of Chieti, 66100 Chieti, Italy
| | - Antonio Valerio
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, University of Chieti, 66100 Chieti, Italy
| | - Michele Di Cosola
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Adriano Piattelli
- School of Dentistry, Saint Camillus International University of Health and Medical Sciences, Via di Sant’Alessandro 8, 00131 Rome, Italy
| | - Virginia Biferi
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, University of Chieti, 66100 Chieti, Italy
| | - Camillo D’Arcangelo
- Unit of Restorative Dentistry and Endodontics, Department of Medical, Oral and Biotechnological Sciences, University of Chieti, 66100 Chieti, Italy
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Qin L, Yao S, Meng W, Zhang J, Shi R, Zhou C, Wu J. Novel antibacterial dental resin containing silanized hydroxyapatite nanofibers with remineralization capability. Dent Mater 2022; 38:1989-2002. [DOI: 10.1016/j.dental.2022.11.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 11/23/2022]
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Impact of Nanoparticles Additions on the Strength of Dental Composite Resin. Int J Biomater 2022; 2022:1165431. [PMID: 35845474 PMCID: PMC9277218 DOI: 10.1155/2022/1165431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 04/09/2022] [Accepted: 06/16/2022] [Indexed: 11/17/2022] Open
Abstract
Objective This study aimed to evaluate the effect of nanoparticles, zirconium dioxide (ZrO2), titanium dioxide (TiO2), and silicon dioxide (SiO2), on flexural strength (FS), hardness, and wear resistance of light cured dental composite resin. Materials and Methods 210 rectangular and disc-shaped composite resin specimens were fabricated with dimensions (25 × 2 × 2 ± 0.03 mm) and (6×4 ± 0.03 mm) for FS, hardness, and wear resistance, respectively (70/test). Specimens of each test were divided according to nanofillers into four groups, unmodified as control, ZrO2 (Z), TiO2 (T), and SiO2 (S) groups; each one was further subdivided into two subgroups according to nanoparticles concentration, 3wt.% and 7wt.% (Z3, Z7, T3, T7, S3, and S7), 10 specimens of each subgroup. A3-point bending test and Vickers hardness test were used for FS and hardness measurements, respectively. Wear resistance was evaluated by the differences in surface roughness of tested specimens before and after wear test. Two-way and 1-way ANOVA and Bonferroni's post hoc tests were done for data analysis (α = 0.05). Results Two-way ANOVA for FS and wear resistance showed that there was a significant interaction between type of nanoparticles and concentration of nanoparticles (p < 0.001) while two-way ANOVA for hardness showed that both type of nanoparticles and concentration of nanoparticles had a significant effect (p < 0.001), while the effect of their interaction was not statistically significant (p=0.142). 1-way-ANOVA test showed significant increase in FS and wear resistance for all tested groups (p < 0.001 and p < 0.001, respectively) except T7 and S7. Also, there was a significant enhancement in hardness for all tested groups (p < 0.001). Conclusion Modification of light cured composite resin with certain amounts of nanoparticles (3% and 7% of ZrO2 and 3% of TiO2 and SiO2) can be beneficial in improving flexural strength and wear resistance while hardness of composite resin was increased with all NPs additions.
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9
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Wang QQ, Wu LP, Zhang S, Tao Y, Li YZ, Zhou QL, Zheng SL, Cao CY, Zhou Z, Li QL. Assembly of Ultralong Hydroxyapatite Nanowires into Enamel-like Materials. J Dent Res 2022; 101:1181-1189. [PMID: 35708455 DOI: 10.1177/00220345221098334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
To develop dental restorative materials with enamel-like structures, ultralong hydroxyapatite (HA) nanowires were synthesized by a hydrothermal method, followed by functionalization with 3-methacryloxypropyltrimethoxysilane (KH-570). The mixture of HA nanowires, KH-570, and light initiator was stirred and centrifuged. The precipitate was vacuum filtered to remove excessive KH-570 and then pressured under cold isostatic pressing (10 MPa × 24 h). Finally, the block was polymerized by lighting. Scanning electron microscopy and transmission electron microscopy showed that HA nanowires with aspect ratios >1,000 were assembled into enamel rod-like microstructures and evenly dispersed in the polymerized KH-570 silane matrix to form enamel-like structures. Thermogravimetric analysis demonstrated that the content of HA nanowires reached 72 wt% in the composite. The enamel-like composite showed a similar hardness, frictional property, and acid-etching property to those of enamel and a comparable or even better diametral tensile strength and compressive strength than some commercial composite resins in mechanical tests in vitro. In addition, the enamel-like composite had good cytocompatibility. Such enamel-like composites may have the potential to be used in biomimetic tooth restorations in the future.
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Affiliation(s)
- Q Q Wang
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - L P Wu
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - S Zhang
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Y Tao
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Y Z Li
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Q L Zhou
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - S L Zheng
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - C Y Cao
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
| | - Z Zhou
- School of Dentistry, University of Detroit Mercy, Detroit, MI, USA
| | - Q L Li
- Key Laboratory of Oral Diseases Research of Anhui Province, College and Hospital of Stomatology, Anhui Medical University, Hefei, China
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Malekhoseini Z, Rezvani MB, Niakan M, Atai M, Bassir MM, Alizade HS, Siabani S. Effect of zinc oxide nanoparticles on physical and antimicrobial properties of resin-modified glass ionomer cement. Dent Res J (Isfahan) 2021; 18:73. [PMID: 34760064 PMCID: PMC8543101 DOI: 10.4103/1735-3327.326646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 01/05/2021] [Accepted: 03/17/2021] [Indexed: 12/03/2022] Open
Abstract
Background: To improve the limitations, many modifications in the resin-modified glass ionomer (RMGI) composition have been proposed. In this study, we evaluated the effect of different concentrations of zinc oxide (ZnO) nanoparticles incorporated into RMGI cement on its physical and antimicrobial properties. Materials and Methods: In this in vitro study, ZnO nanoparticles with 0–4 wt.% concentrations were incorporated into RMGI. The following tests were carried out: (a) Antibacterial activity against Streptococcus mutans tested by disc diffusion method, (b) mechanical behavior assessment by measuring flexural strength (FS) and flexural modulus (FM), (c) micro-shear bond strength (μ-SBS), and (d) fluoride and zinc release. Data were analyzed using the statistical tests of ANOVA, t-test, and Tukey's HSD post hoc in SPSS V22. The level of significancy was 0.05. Results: In the disc diffusion method, specimens with 2 wt.% ZnO nanoparticles showed the highest antimicrobial efficacy (P < 0.05). After 1 month of water storage, no significant difference was observed in FS and FM of the samples (P > 0.05). In 2 wt.% ZnO nanoparticles group, μSBS increased in the first 7 days but decreased by 17% after one month, which showed a significant difference with that of the control group. The fluoride release did no change in the ZnO nanoparticle-containing group compared with the control group at all time intervals. Conclusion: Incorporation of 2 wt.% ZnO nanoparticles into the RMGI cement adds antimicrobial activity to the cement without sacrificing FS and fluoride release properties, while decreased μSBS.
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Affiliation(s)
- Zahra Malekhoseini
- Department of Operative Dentistry, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | | | - Mohammad Niakan
- Department of Microbiology, Faculty of Medicine, Shahed University, Tehran, Iran
| | - Mohammad Atai
- Department of Polymer Science, Iran Polymer and Petrochemical Institute, Tehran, Iran
| | | | | | - Saba Siabani
- Department of Operative Dentistry, School of Dentistry, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Amin F, Rahman S, Khurshid Z, Zafar MS, Sefat F, Kumar N. Effect of Nanostructures on the Properties of Glass Ionomer Dental Restoratives/Cements: A Comprehensive Narrative Review. MATERIALS (BASEL, SWITZERLAND) 2021; 14:6260. [PMID: 34771787 PMCID: PMC8584882 DOI: 10.3390/ma14216260] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/14/2021] [Accepted: 10/15/2021] [Indexed: 12/16/2022]
Abstract
Overall perspective of nanotechnology and reinforcement of dental biomaterials by nanoparticles has been reported in the literature. However, the literature regarding the reinforcement of dental biomaterials after incorporating various nanostructures is sparse. The present review addresses current developments of glass ionomer cements (GICs) after incorporating various metallic, polymeric, inorganic and carbon-based nanostructures. In addition, types, applications, and implications of various nanostructures incorporated in GICs are discussed. Most of the attempts by researchers are based on the laboratory-based studies; hence, it warrants long-term clinical trials to aid the development of suitable materials for the load bearing posterior dentition. Nevertheless, a few meaningful conclusions are drawn from this substantial piece of work; they are as follows: (1) most of the nanostructures are likely to enhance the mechanical strength of GICs; (2) certain nanostructures improve the antibacterial activity of GICs against the cariogenic bacteria; (3) clinical translation of these promising outcomes are completely missing, and (4) the nanostructured modified GICs could perform better than their conventional counterparts in the load bearing posterior dentition.
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Affiliation(s)
- Faiza Amin
- Science of Dental Materials Department, Dow Dental College, Dow University of Health Sciences, Karachi 74200, Pakistan;
| | - Sehrish Rahman
- Science of Dental Materials Department, Dr. Ishrat Ul Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, Karachi 74200, Pakistan; (S.R.); (N.K.)
| | - Zohaib Khurshid
- Department of Prosthodontics and Dental Implantology, College of Dentistry, King Faisal University, Al-Ahsa 31982, Saudi Arabia
| | - Muhammad Sohail Zafar
- Department of Restorative Dentistry, College of Dentistry, Taibah University, Al Madinah, Al Munawwarah 41311, Saudi Arabia;
- Department of Dental Materials, Islamic International Dental College, Riphah International University, Islamabad 44000, Pakistan
| | - Farshid Sefat
- Department of Biomedical and Electronics Engineering, School of Engineering, University of Bradford, Bradford BD7 1DP, UK;
| | - Naresh Kumar
- Science of Dental Materials Department, Dr. Ishrat Ul Ebad Khan Institute of Oral Health Sciences, Dow University of Health Sciences, Karachi 74200, Pakistan; (S.R.); (N.K.)
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Liu J, Zhang H, Sun H, Liu Y, Liu W, Su B, Li S. The Development of Filler Morphology in Dental Resin Composites: A Review. MATERIALS (BASEL, SWITZERLAND) 2021; 14:5612. [PMID: 34640020 PMCID: PMC8509641 DOI: 10.3390/ma14195612] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 11/17/2022]
Abstract
Dental resin composites (DRCs) with diverse fillers added are widely-used restorative materials to repair tooth defects. The addition of fillers brings an improvement in the mechanical properties of DRCs. In the past decade, diverse fillers have emerged. However, the change of emerging fillers mainly focuses on the chemical composition, while the morphologic characteristics changes are often ignored. The fillers with new morphologies not only have the advantages of traditional fillers (particles, fibrous filler, etc.), but also endow some additional functional characteristics (stronger bonding ability to resin matrix, polymerization resistance, and wear resistance, drug release control ability, etc.). Moreover, some new morphologies are closely related to the improvement of traditional fillers, porous filler vs. glass particles, core-sheath fibrous vs. fibrous, etc. Some other new morphology fillers are combinations of traditional fillers, UHA vs. HA particles and fibrous, tetrapod-like whisker vs. whisker and fibrous filler, mesoporous silica vs. porous and silica particles. In this review, we give an overall description and a preliminary summary of the fillers, as well as our perspectives on the future direction of the development of novel fillers for next-generation DRCs.
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Affiliation(s)
- Jiani Liu
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi’an 710032, China; (J.L.); (H.Z.); (Y.L.); (W.L.)
- The Affiliated Hospital of Stomatology, School of Stomatology, Zhejiang University School of Medicine, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou 310006, China
| | - Hao Zhang
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi’an 710032, China; (J.L.); (H.Z.); (Y.L.); (W.L.)
| | - Huijun Sun
- Bristol Dental School, University of Bristol, Lower Maudlin Street, Bristol BS1 2LY, UK; (H.S.); (B.S.)
| | - Yanru Liu
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi’an 710032, China; (J.L.); (H.Z.); (Y.L.); (W.L.)
| | - Wenlin Liu
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi’an 710032, China; (J.L.); (H.Z.); (Y.L.); (W.L.)
| | - Bo Su
- Bristol Dental School, University of Bristol, Lower Maudlin Street, Bristol BS1 2LY, UK; (H.S.); (B.S.)
| | - Shibao Li
- State Key Laboratory of Military Stomatology and National Clinical Research Center for Oral Diseases, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi’an 710032, China; (J.L.); (H.Z.); (Y.L.); (W.L.)
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Chong YT, Tan CSH, Liu LY, Liu J, Teng CP, Wang F. Enhanced dispersion of hydroxyapatite whisker in orthopedics
3D
printing resin with improved mechanical performance. J Appl Polym Sci 2021. [DOI: 10.1002/app.50811] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Yi Ting Chong
- Polymer Composites Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Singapore Singapore
| | - Clara S. H. Tan
- Department of Chemistry National University of Singapore Singapore Singapore
| | - Li Ying Liu
- Department of Chemistry National University of Singapore Singapore Singapore
| | - Jinyan Liu
- National Engineering Research Center for Healthcare Devices Guangdong Key Lab of Medical Electronic Instruments and Polymer Material Products, Guangdong Institute of Medical Instruments Guangzhou China
| | - Choon Peng Teng
- Polymer Composites Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Singapore Singapore
| | - FuKe Wang
- Polymer Composites Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Singapore Singapore
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Amiri P, Talebi Z, Semnani D, Bagheri R, Fashandi H. Improved performance of Bis-GMA dental composites reinforced with surface-modified PAN nanofibers. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2021; 32:82. [PMID: 34191135 PMCID: PMC8245374 DOI: 10.1007/s10856-021-06557-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/07/2021] [Indexed: 06/13/2023]
Abstract
In the present work, polyacrylonitrile (PAN) nanofibers reinforced dental composites were investigated to achieve the improved interfacial adhesion between the PAN nanofiber and resin matrix using surface modification of nanofibers. PAN nanofibers mat were prepared by electrospinning and then, surface treated with the activated bisphenol A glycidyl methacrylate (Bis-GMA)/triethyleneglycol dimethacrylate (TEGDMA) (50/50 mass ratio) dental resin followed by photo-curing. Also, the treated nanofibers mat was milled into a powder to achieve the uniform distribution of nanofibers in the matrix resin. The reinforced dental composite were prepared by mixing the various mass fraction of the powder (0.5-15 wt%) with the Bis-GMA/TEGDMA dental monomers. The effect of weight ratio of surface-modified nanofibers to blend resin on the chemical structure, morphology, compression and flexural properties, color and polymerization shrinkage of dental composites was evaluated. The results showed that using surface-treated nanofibers with content of 5 wt% enhanced the compression strength, flexural strength, flexural modulus and work of rupture of the resultant dental composite by factors of 23%, 7%, 80%, and 145%, respectively, comparing to the unreinforced neat resin. Also, the polymerization shrinkage reduces by 37%. These significant improved properties of the dental composite could be due to the semi-interpenetration network formation between surface-modified nanofibers and resin matrix and well distribution of nanofibers in the dental resin. Further increasing the nanofiber content led to poor mechanical properties of obtained dental composites. The results also, revealed that the color of resin composite could be whiter using modified PAN nanofibers as the filler.
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Affiliation(s)
- Parisa Amiri
- Department of Textile Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Zahra Talebi
- Department of Textile Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran.
| | - Dariush Semnani
- Department of Textile Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Rouhollah Bagheri
- Department of Chemical Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
| | - Hossein Fashandi
- Department of Textile Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran
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Ritto FP, da Silva EM, Borges ALS, Borges MAP, Sampaio-Filho HR. Fabrication and characterization of low-shrinkage dental composites containing montmorillonite nanoclay. Odontology 2021; 110:35-43. [PMID: 34156565 DOI: 10.1007/s10266-021-00629-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 06/14/2021] [Indexed: 11/25/2022]
Abstract
Dental composites are aesthetic materials widely used in Dentistry for replacing hard dental tissues lost due to caries or traumas. The aim of this study was to fabricate low-shrinkage dental composite charged with nanoclay fillers (montmorillonite Cloisite®-MMT) and evaluate their cytotoxicity and physicomechanical properties. Four dental composites were produced from the same organic matrix: Bis-GMA/TEGDMA (30 wt.%). The filler system was constituted of BaSi, SiO2, and MMT in the following concentrations (wt.%): 93.8/6.2/0, 89.1/5.9/5, 86.7/5.8/7.5, and 84.4/5.6/10 (E0: 0; E5: 5%; E7.5: 7.5%; E10: 10% of MMT nanoclays). The following properties were tested: in vitro cytotoxicity, flexural strength, elastic modulus, volumetric shrinkage, water sorption, water solubility, and hygroscopic expansion. Scanning electron microscopy was used to characterize composites' topography. Data were analyzed by one-way ANOVA and Tukey's HSD post hoc test (p < 0.05). MMT nanoclays did not affect the cytotoxicity. E5 and E7.5 groups showed a significant decrease in polymerization shrinkage while maintained the overall physicomechanical properties. The inclusion of 5 and 7.5 wt.% of MMT nanoclays allowed the fabrication of dental composites with low cytotoxicity and low polymerization shrinkage, without jeopardizing the overall behaviour of their physicomechanical properties (flexural strength, elastic modulus, water sorption, water solubility, and hygroscopic expansion). These aspects suggest that the usage of MMT nanoclays could be an effective strategy to formulate new dental composites with clinical applicability.
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Affiliation(s)
- Fernanda Pitta Ritto
- Department of Operative Dentistry, College of Dentistry, Oklahoma University, Oklahoma, USA
| | - Eduardo Moreira da Silva
- Analytical Laboratory of Restorative Biomaterials-LABiom-R, Faculdade de Odontologia, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil
| | - Alexandre Luiz Souto Borges
- Department of Dental Materials and Prosthodontics, School of Dentistry, São Paulo State University-UNESP, São Jose Dos Campos, SP, Brazil
| | - Márcio Antônio Paraizo Borges
- Department of Operative Dentistry, IOPUC, Rua Marquês de São Vicente, 389-Gávea, Rio de Janeiro, RJ, 22451-047, Brazil.
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Sun G, Huang Y, Li D, Fan Q, Xu J, Shao J. Blue Light Induced Photopolymerization and Cross-Linking Kinetics of Poly(acrylamide) Hydrogels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:11676-11684. [PMID: 32969661 DOI: 10.1021/acs.langmuir.0c02560] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Blue light induced photopolymerization and photo-cross-linking kinetics of acrylamide (AM), with camphorquinone/diphenyl iodonium hexafluorophosphate (CQ/DPI) as photoinitiators, were investigated. The effects of a number of parameters, including mass fraction of CQ, DPI, and AM (wCQ, wDPI, and wAM) and light intensity (I), on photopolymerization efficiency and photogelation process were systematically studied by photo-differential scanning calorimetry (DSC) and photo-rheometry. Photo-DSC indicated that the maximum photopolymerization rate (Rp, max) was proportional to wCQ0.5, wDPI0.5, I0.5, and wAM, while Photo-Rheometry showed linear relationships between gel time tgel and wCQ and I, respectively, and power law relationships between tgel and wDPI and wAM, respectively. In addition, both peak cross-linking rate Rc,max, and delay time td, which were both linearly proportional to wCQ0.5, wDPI0.5, and I0.5, showed power law relationships with wAM. Furthermore, exponential patterns were observed between all these factors, wCQ, wDPI, wAM, and I and plateau modulus G'∞. Combining such correlations obtained from experimental data, an empirical model was established describing the projected mechanical properties of poly(acrylamide) hydrogels from blue light initiated photopolymerization and photo-cross-linking.
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Affiliation(s)
- Guangdong Sun
- Engineering Research Center for Eco-Dyeing and Finishing of Textiles, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | - Yi Huang
- Engineering Research Center for Eco-Dyeing and Finishing of Textiles, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
| | - Dapeng Li
- Department of Bioengineering, University of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, United States
| | - Qinguo Fan
- Department of Bioengineering, University of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, United States
| | - Jin Xu
- Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, P. R. China
| | - Jianzhong Shao
- Engineering Research Center for Eco-Dyeing and Finishing of Textiles, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou 310018, P. R. China
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Non-silicate nanoparticles for improved nanohybrid resin composites. Dent Mater 2020; 36:1314-1321. [PMID: 32758374 DOI: 10.1016/j.dental.2020.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 07/11/2020] [Accepted: 07/11/2020] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Zirconia and alumina nanoparticles were coated with a silica-rich layer (ALSI and ZRSI) and used to prepare experimental nanohybrid resin composites, which were characterized and compared to a control commercial resin composite (Filtek Z350 XT). METHODS Silica nanoparticles with sizes compatible to ALSI (Aerosil 150) and ZRSI (Aerosil OX 50) were tested as references. The volume of nanoparticles was equivalent across the composites, which also had consistent content of glass microparticles. CC conversion, viscosity, depth of cure, surface topography, hardness, opacity, radio-opacity, and edge chipping resistance (ReA) were tested after 24 h. Flexural strength (σf) and fracture toughness (KIC) were also tested after 15 K thermal cycles. Data were analyzed using one-way or two-way ANOVA and Tukey's test (α = 0.05). RESULTS ALSI and ZRSI yielded resin composites with lower viscosity and more irregular nanoagglomerates compared to nanosilica-based composites. CC conversion and depth of cure were lower for ZRSI composite, which had higher opacity, radio-opacity, and hardness. ReA was higher for ALSI composite. Composites with ALSI and ZRSI showed stable σf after aging, whereas the control and Aerosil 150 resin composites showed significant degradation. The commercial and nanosilica-based composites showed up to 42% reduction in KIC after aging, whereas resin composites with ZRSI and ALSI showed a more stable KIC. SIGNIFICANCE ALSI and ZRSI generated nanohybrid resin composites with improved and/or more stable physical properties compared with nanosilica-based and commercial composites. This study suggests that changing the composition of nanofillers is a simple method to enhance the performance of nanohybrid composites.
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Encalada-Alayola JJ, Veranes-Pantoja Y, Uribe-Calderón JA, Cauich-Rodríguez JV, Cervantes-Uc JM. Effect of Type and Concentration of Nanoclay on the Mechanical and Physicochemical Properties of Bis-GMA/TTEGDMA Dental Resins. Polymers (Basel) 2020; 12:E601. [PMID: 32155803 PMCID: PMC7182935 DOI: 10.3390/polym12030601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 02/27/2020] [Accepted: 03/03/2020] [Indexed: 11/22/2022] Open
Abstract
Bis-GMA/TTEGDMA-based resin composites were prepared with two different types of nanoclays: an organically modified laminar clay (Cloisite® 30B, montmorillonite, MMT) and a microfibrous clay (palygorskite, PLG). Their physicochemical and mechanical properties were then determined. Both MMT and PLG nanoclays were added into monomer mixture (1:1 ratio) at different loading levels (0, 2, 4, 6, 8 and 10 wt.%), and the resulting composites were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA) and mechanical testing (bending and compressive properties). Thermal properties, depth of cure and water absorption were not greatly affected by the type of nanoclay, while the mechanical properties of dental resin composites depended on both the variety and concentration of nanoclay. In this regard, composites containing MMT displayed higher mechanical strength (both flexural and compression) than those resins prepared with PLG due to a poor nanoclay dispersion as revealed by SEM. Solubility of the composites was dependent not only on nanoclay-type but also the mineral concentration. Dental composites fulfilled the minimum depth cure and solubility criteria set by the ISO 4049 standard. In contrast, the minimum bending strength (50 MPa) established by the international standard was only satisfied by the dental resins containing MMT. Based on these results, composites containing either MMT or PLG (at low filler contents) are potentially suitable for use in dental restorative resins, although those prepared with MMT displayed better results.
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Affiliation(s)
- J. J. Encalada-Alayola
- Centro de Investigación Científica de Yucatán, A.C. Unidad de Materiales, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo C.P. Mérida 97205, Mexico; (J.J.E.-A.); (J.A.U.-C.); (J.V.C.-R.)
| | - Y. Veranes-Pantoja
- Centro de Biomateriales, Universidad de La Habana, Avenida Universidad, s/n, e/G y Ronda, C.P. La Habana 10600, Cuba;
| | - J. A. Uribe-Calderón
- Centro de Investigación Científica de Yucatán, A.C. Unidad de Materiales, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo C.P. Mérida 97205, Mexico; (J.J.E.-A.); (J.A.U.-C.); (J.V.C.-R.)
| | - J. V. Cauich-Rodríguez
- Centro de Investigación Científica de Yucatán, A.C. Unidad de Materiales, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo C.P. Mérida 97205, Mexico; (J.J.E.-A.); (J.A.U.-C.); (J.V.C.-R.)
| | - J. M. Cervantes-Uc
- Centro de Investigación Científica de Yucatán, A.C. Unidad de Materiales, Calle 43 No. 130 x 32 y 34, Col. Chuburná de Hidalgo C.P. Mérida 97205, Mexico; (J.J.E.-A.); (J.A.U.-C.); (J.V.C.-R.)
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Pratap B, Gupta RK, Bhardwaj B, Nag M. Modeling based experimental investigation on polymerization shrinkage and micro-hardness of nano alumina filled resin based dental material. J Mech Behav Biomed Mater 2019; 99:86-92. [DOI: 10.1016/j.jmbbm.2019.06.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/18/2019] [Accepted: 06/26/2019] [Indexed: 10/26/2022]
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Khosravani MR. Mechanical behavior of restorative dental composites under various loading conditions. J Mech Behav Biomed Mater 2019; 93:151-157. [PMID: 30798181 DOI: 10.1016/j.jmbbm.2019.02.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 02/07/2019] [Accepted: 02/11/2019] [Indexed: 12/12/2022]
Abstract
Mechanical engineering and its scientific principles constitute an essential core in medical science. Currently, different composite resins are widely used as restorative dental materials. However, their lack of adequate strength and toughness has led to research that is aimed at improving the mechanical properties of dental composites. In the present study, the behavior of three different dental materials is investigated under static and dynamic loading conditions. In the experimental tests, a split Hopkinson pressure bar is utilized which corresponds to the most commonly used experimental setup for examining material behavior under a high rate of loading. The examined dental composites experience impacts during their service life and also during car accidents or sport injuries. Hence, in the study, impact loading is modeled in an experiment. A series of compression tests is conducted from low to high strain rates up to 40s-1, and the dynamic elastic moduli of three different dental composites are measured. Furthermore, studies on the compressed surface of the dental composite specimens are performed to improve the analysis with respect to the hardness of the materials. The responses of the examined composites to dynamic loadings verify the impact resistance of the materials. The results indicate the load-carrying capabilities of the dental composites. These results can be used for materials development and existing computational models.
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Makvandi P, Jamaledin R, Jabbari M, Nikfarjam N, Borzacchiello A. Antibacterial quaternary ammonium compounds in dental materials: A systematic review. Dent Mater 2018; 34:851-867. [PMID: 29678327 DOI: 10.1016/j.dental.2018.03.014] [Citation(s) in RCA: 172] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 03/20/2018] [Accepted: 03/23/2018] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Quaternary ammonium compounds (QACs) represent one of the most effective classes of disinfectant agents in dental materials and resin nanocomposites. This reviews aims to give a wide overview on the research in the field of antibacterial QACs in dental materials and nanocomposites. METHOD An introduction to dental materials components as well as the microorganisms and methods of evaluation for the antimicrobial assays are presented. Then, the properties and synthesis route of QACs, as monomer and filler, are shown. Finally, antimicrobial monomers and fillers, specifically those contain quaternary ammonium salts (QASs), in dental materials are reviewed. RESULTS QACs have been used as monomer and micro/nanofiller in restorative dentistry. They possess one or more methacrylate functional groups to participate in polymerization reactions. QACs with multiple methacrylate groups can also be used as crosslinking agents. Furthermore, QACs with chain length from ∼12 to 16 have higher antimicrobial activity in cured dental resins. In general, increasing the chain length leads to a threshold value (critical point) and then it causes decrease in the antimicrobial activity. SIGNIFICANCE The current state of the art of dental materials and resin nanocomposites includes a wide variety of antimicrobial materials. Among them, QACs presents low cytotoxicity and excellent long-term antimicrobial activity without leaching out over time.
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Affiliation(s)
- Pooyan Makvandi
- Institute for Polymers, Composites and Biomaterials (IPCB), National Research Council (CNR), Naples, Italy; Institute for Advanced Studies in Basic Sciences, Zanjan, Iran.
| | - Rezvan Jamaledin
- Center for Advanced Biomaterials for Health Care, Istituto Italiano di Tecnologia (IIT@CRIB), Napels, Italy
| | - Mostafa Jabbari
- Swedish Centre for Resource Recovery, University of Borås, Borås SE-50190, Sweden
| | | | - Assunta Borzacchiello
- Institute for Polymers, Composites and Biomaterials (IPCB), National Research Council (CNR), Naples, Italy.
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Saleh Mohammadnia M, Hemmati S, Ghasemi N. Preparation of Reinforced poly (BisGMA-UDMA) Graphene-Based Nanocomposites Via Moderate in Situ SET-LRP. JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY 2017. [DOI: 10.1080/10601325.2017.1387487] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
| | - Salar Hemmati
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nahid Ghasemi
- Department of Chemistry, Sciences Faculty, Arak Branch, Islamic Azad University, Arak, Iran
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M* M, ME B. Fractography and Mechanical Properties of Urethane Dimethacrylate Dental Composites Reinforced with Glass Nanoparticles. JOURNAL OF DENTAL BIOMATERIALS 2016; 3:327-334. [PMID: 28959761 PMCID: PMC5608046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
STATEMENT OF PROBLEM Dental resin composites are becoming prevalent in restorative dentistry and have almost replaced amalgam nowadays. Consequently, their mechanical properties and durability are critical. OBJECTIVES The aim of this study was to produce Pyrex glass nano-particles by wet milling process and use them as reinforcement in dental resins for anterior restorations and then examination of fractographic properties of these composites. MATERIALS AND METHODS The glass nano-particles were achieved via wet milling. The surface of the particles was modified with 3-(Trimethoxysilyl) propyl methacrylate (γ-MPTMS) silane in order to improve their surface. Fourier transform infra-red (FTIR) analysis showed that the silane groups provided double bonds to the surface of the particles and prevented agglomeration. Then, the composite resins were made with different weight percentages of Pyrex glass. The mechanical properties of samples flexural test were evaluated. The required energy for fracture of the specimens was achieved via this test. The fracture surfaces of the samples were analyzed using a scanning electron microscope (SEM) in order to explain the mechanisms of fracture. RESULTS The results and analysis showed that increasing the glass nano-particles mass fraction had a great effect on mechanical properties of the composites due to the mechanisms of crack propagation and crack deflection as well as preventing void formation. The effective energy dissipation mechanisms such as crack pinning and deflection, was observed in SEM micrographs. CONCLUSIONS Void formation in the low filler content composite is one of the mechanisms to decrease the energy required for fracture of these composites and eventually weaken them.
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Lung CYK, Sarfraz Z, Habib A, Khan AS, Matinlinna JP. Effect of silanization of hydroxyapatite fillers on physical and mechanical properties of a bis-GMA based resin composite. J Mech Behav Biomed Mater 2016; 54:283-94. [DOI: 10.1016/j.jmbbm.2015.09.033] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Revised: 09/22/2015] [Accepted: 09/29/2015] [Indexed: 10/22/2022]
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Okoronkwo EA, Imoisili PE, Olubayode SA, Olusunle SOO. Development of Silica Nanoparticle from Corn Cob Ash. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/anp.2016.52015] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Okulus Z, Buchwald T, Voelkel A. Characterization of light-cured, dental-resin-based biocomposites. J Appl Polym Sci 2015. [DOI: 10.1002/app.42812] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Zuzanna Okulus
- Institute of Chemical Technology and Engineering; Poznań University of Technology; ul. Berdychowo 4 60-965 Poznań Poland
| | - Tomasz Buchwald
- Faculty of Technical Physics; Poznań University of Technology; ul. Piotrowo 3 60-965 Poznań Poland
| | - Adam Voelkel
- Institute of Chemical Technology and Engineering; Poznań University of Technology; ul. Berdychowo 4 60-965 Poznań Poland
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Zuo KH, Lu LM, Zeng YP. The mechanical properties of β-Si 3N 4whiskers-reinforced dental resin composites. J Appl Polym Sci 2014. [DOI: 10.1002/app.40692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kai-Hui Zuo
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Shanghai 200050 China
| | - Li-Min Lu
- Systems Design Engineering; University of Waterloo; City of Waterloo Canada
| | - Yu-Ping Zeng
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure; Shanghai Institute of Ceramics; Shanghai 200050 China
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Li X, Liu W, Sun L, Aifantis KE, Yu B, Fan Y, Feng Q, Cui F, Watari F. Resin composites reinforced by nanoscaled fibers or tubes for dental regeneration. BIOMED RESEARCH INTERNATIONAL 2014; 2014:542958. [PMID: 24982894 PMCID: PMC4058202 DOI: 10.1155/2014/542958] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Accepted: 03/04/2014] [Indexed: 12/20/2022]
Abstract
It has been stated clearly that nanofillers could make an enhancement on the mechanical performances of dental composites. In order to address current shortage of traditional dental composites, fillers in forms of nanofibers or nanotubes are broadly regarded as ideal candidates to greatly increase mechanical performances of dental composites with low content of fillers. In this review, the efforts using nanofibers and nanotubes to reinforce mechanical performances of dental composites, including polymeric nanofibers, metallic nanofibers or nanotubes, and inorganic nanofibers or nanotubes, as well as their researches related, are demonstrated in sequence. The first purpose of current paper was to confirm the enhancement of nanofibers or nanotubes' reinforcement on the mechanical performances of dental restorative composite. The second purpose was to make a general description about the reinforcement mechanism of nanofibers and nanotubes, especially, the impact of formation of interphase boundary interaction and nanofibers themselves on the advanced mechanical behaviors of the dental composites. By means of the formation of interface interaction and poststretching nanofibers, reinforced effect of dental composites by sorts of nanofibers/nanotubes has been successfully obtained.
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Affiliation(s)
- Xiaoming Li
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Wei Liu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Lianwen Sun
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | | | - Bo Yu
- Department of Orthopedics, Zhujiang Hospital of Southern Medical University, Guangzhou 510282, China
| | - Yubo Fan
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Qingling Feng
- State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084, China
| | - Fuzhai Cui
- State Key Laboratory of New Ceramics and Fine Processing, Tsinghua University, Beijing 100084, China
| | - Fumio Watari
- Department of Biomedical Materials and Engineering, Graduate School of Dental Medicine, Hokkaido University, Sapporo 060-8586, Japan
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Jun SK, Kim DA, Goo HJ, Lee HH. Investigation of the correlation between the different mechanical properties of resin composites. Dent Mater J 2014; 32:48-57. [PMID: 23370870 DOI: 10.4012/dmj.2012-178] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aim of this study was to investigate the relationship between the different mechanical properties with the filler fraction of various resin composites. Mechanical properties of eighteen different resin composites were investigated in this study; flexural strength (FS), flexural modulus (FM), fracture toughness (FT), compressive strength (CS), diametral tensile strength (DTS), Barcol hardness (BH), Vickers hardness (HV), and Knoop hardness (HK). The mean values of mechanical properties and the filler fractions (V(f )) obtained from the literature and the manufacturer were analyzed using Pearson's correlation test at p<0.01. The relationships were compared with the data retrieved from previous studies. Strong correlations between Vf and BH/HV/HK and V(f) and FM were evident in the results of the present study and these results were supported by the retrieved data from previous studies. The other relationships between mechanical properties, such as that between FS and FM and between CS and HV were not significant.
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Affiliation(s)
- Soo-Kyung Jun
- Department of Oral Health, Graduate School of Dankook University, Cheonan, Korea
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Timpe N, Fullriede H, Borchers L, Stiesch M, Behrens P, Menzel H. Nanoporous silica nanoparticles with spherical and anisotropic shape as fillers in dental composite materials. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/bnm-2014-0010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe objective of this study was to test whether nanoporous silica nanoparticles can be employed as fillers in dental composite materials to improve their mechanical properties. These nanoporous silica nanoparticles were synthesized using sol-gel methods, in part modified by silanization, and thoroughly characterized. The nanoporous nanoparticles were added to dental resins to form nanocomposites (resins impregnated with nanoparticles) and hybrid composites (containing in addition conventional microfillers). The incorporation of these nanoporous nanoparticles in dental resins or composites was characterized by investigation of the complex viscosity and double bond conversion as well as by determination of flexural strength and Young’s modulus. The dispersion of the nanofillers was examined by SEM and EDX imaging of fracture surfaces. Incorporation of small contents (1–3 wt%) of unmodified nanoporous particles leads to improved mechanical properties. However, the incorporation of larger contents results in particle agglomeration and declining mechanical properties. This effect is less pronounced when the surface of the particles is modified with methacrylate residues, resulting in a lower agglomeration tendency and a more homogeneous filler dispersion. Surface properties and, concomitantly, dispersibility of the nanoparticles have a strong influence on mechanical properties. But the incorporation of nanoporous instead of solid nanoparticles into dental composite materials is indeed a possibility to improve the mechanical behavior. However, modification of the surface is necessary and the key to achieving uniform dispersion and, thereby, improving mechanical properties.
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Kumar N. Inconsistency in the strength testing of dental resin-based composites among researchers. Pak J Med Sci 2013; 29:205-10. [PMID: 24353541 PMCID: PMC3809204 DOI: 10.12669/pjms.291.2922] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 11/03/2012] [Accepted: 11/05/2012] [Indexed: 11/25/2022] Open
Abstract
The aims of this paper were to review the current strength testing methods of the dental resin-based composites (RBCs) and to explore the inconsistencies with regard to strength testing among researchers. Data selection/extraction: An outline of the most relevant aspects of RBCs was created, and a subsequent literature search for articles published during last four decades (1970-2010) was conducted using the databases, namely PubMed, Science Direct and ISI Web of Knowledge. Conclusion: The literature review highlighted a lack of consensus among researchers regarding the reliability of ISO recommended three-point flexure strength testing method. Several investigators have used Weibull statistics for the analysis of RBCs strength data, however their applicability might be questioned as many RBCs contain greater resin content and may exhibit sufficient viscous deformation prior to brittle failure. In addition, variability in the selection of cross-head speed and mould material for strength testing was evident which may lead to variation in the strength data and render the interpretation difficult among researchers.
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Affiliation(s)
- Naresh Kumar
- Dr. Naresh Kumar, PhD, Assistant Professor, Science of Dental Materials Department, Institute of Dentistry, Liaquat University of Medical & Health Sciences, Jamshoro, Pakistan
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Jain S, Jain AP, Jain S, Gupta ON, Vaidya A. WITHDRAWN: Nanotechnology: An emerging area in the field of dentistry. J Dent Sci 2013. [DOI: 10.1016/j.jds.2013.08.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Cheng L, Zhou X, Zhong H, Deng X, Cai Q, Yang X. NaF-loaded core-shell PAN-PMMA nanofibers as reinforcements for Bis-GMA/TEGDMA restorative resins. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013; 34:262-9. [PMID: 24268258 DOI: 10.1016/j.msec.2013.09.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Revised: 08/30/2013] [Accepted: 09/18/2013] [Indexed: 10/26/2022]
Abstract
A kind of core-shell nanofibers containing sodium fluoride (NaF) was produced and used as reinforcing materials for dimethacrylate-based dental restorative resins in this study. The core-shell nanofibers were prepared by coaxial-electrospinning with polyacrylonitrile (PAN) and poly(methyl methacrylate) (PMMA) solutions as core and shell fluids, respectively. The produced PAN-PMMA nanofibers varied in fiber diameter and the thickness of PMMA shell depending on electrospinning parameters. NaF-loaded nanofibers were obtained by incorporating NaF nanocrystals into the core fluid at two loadings (0.8 or 1.0wt.%). Embedment of NaF nanocrystals into the PAN core did not damage the core-shell structure. The addition of PAN-PMMA nanofibers into Bis-GMA/TEGDMA clearly showed the reinforcement due to the good interfacial adhesion between fibers and resin. The flexural strength (Fs) and flexural modulus (Ey) of the composites decreased slightly as the thickness of PMMA shell increasing. Sustained fluoride releases with minor initial burst release were achieved from NaF-loaded core-shell nanofibers and the corresponding composites, which was quite different from the case of embedding NaF nanocrystals into the dental resin directly. The study demonstrated that NaF-loaded PAN-PMMA core-shell nanofibers were not only able to improve the mechanical properties of restorative resin, but also able to provide sustained fluoride release to help in preventing secondary caries.
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Affiliation(s)
- Liyuan Cheng
- Beijing Laboratory of Biomedical Materials, State Key Laboratory of Organic-inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, PR China
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Houshyar A, Khavandi AR, Javadpour J, Samani S, Naimi-Jamal MR, Atai M. Enhancement of mechanical properties of experimental composite by Fuller's earth nanofibers for cervical restoration. J Biomed Mater Res B Appl Biomater 2013; 101:911-8. [DOI: 10.1002/jbm.b.32896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 11/26/2012] [Accepted: 12/11/2012] [Indexed: 11/10/2022]
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Lu LM, Zuo KH, Zeng YP. Fabrication and properties of surface-modified β-Si3N4whiskers reinforced dental resin composites. J Appl Polym Sci 2012. [DOI: 10.1002/app.38125] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Habekost LV, Camacho GB, Lima GS, Ogliari FA, Cubas GB, Moraes RR. Nanoparticle loading level and properties of experimental hybrid resin luting agents. J Prosthodont 2012; 21:540-5. [PMID: 22672507 DOI: 10.1111/j.1532-849x.2012.00867.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
PURPOSE This study investigated the influence of nanoparticle loading level on properties of experimental hybrid resin luting agents. MATERIALS AND METHODS Silanated 2-μm barium borosilicate glass microparticles and 7-nm silica nanoparticles were used. Five materials were obtained by loading a photocurable Bis-GMA/TEGDMA co-monomer with a total mass fraction of 60% inorganic fillers. The mass fraction of nanoparticles was set at 0% (control), 1% (G1), 2.5% (G2.5), 5% (G5), or 10% (G10). The properties evaluated were flexural strength (σ) and modulus (E(f) ), Knoop hardness number (KHN), and film thickness (FT). Dispersion/interaction of the particles with the resin phase was assessed by scanning electron microscopy (SEM). Data were submitted to statistical analysis (5%). RESULTS For σ, G1 > G2.5 = G5 = G10, and control > G10. For E(f) , G2.5 > control = G1 > G5 > G10. For KHN, G5 = G10 > control = G1 = G2.5. For FT, G10 = G5 > control = G1, and G10 > G2.5. Incorporation of nanoparticles was associated with observation of clusters in the SEM analysis. The clusters were more frequent for higher nanoparticle loadings. CONCLUSION Modest incorporation of nanoparticles may improve the properties of resin luting materials. Nanofiller mass fractions above 2.5% should, however, be avoided because they may be detrimental to the properties of the resin luting agents.
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Affiliation(s)
- Luciano V Habekost
- School of Dentistry, Federal University of Pelotas, Rua Goncalves Chaves 457, Pelotas, Brazil
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Chen L, Yu Q, Wang Y, Li H. BisGMA/TEGDMA dental composite containing high aspect-ratio hydroxyapatite nanofibers. Dent Mater 2011; 27:1187-95. [PMID: 21937098 DOI: 10.1016/j.dental.2011.08.403] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Revised: 05/23/2011] [Accepted: 08/25/2011] [Indexed: 11/17/2022]
Abstract
OBJECTIVES The objectives of this study are to investigate the properties of high aspect-ratio hydroxyapatite (HAP) nanofibers and the reinforcing effect of such fibers on bisphenol A glycidyl methacrylate (BisGMA)/triethylene glycol dimethacrylate (TEGDMA) dental resins (without silica microparticle filler) and dental composites (with silica microparticle filler) with various mass fractions (loading rates). METHODS HAP nanofibers were synthesized using a wet-chemical method and characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and thermal gravimetric analysis (TGA). Biaxial flexural strength (BFS) of the HAP nanofibers reinforced dental resins without any microsized filler and dental composites with silica microparticle filler was tested and analysis of variance (ANOVA) was used for the statistically analysis of acquired data. The morphology of fracture surface of tested dental composite samples was examined by SEM. RESULTS The HAP nanofibers with aspect-ratios of 600 to 800 can be successfully fabricated with a simple wet-chemical method in aqueous solution. Impregnation of small mass fractions of the HAP nanofibers (5 wt% or 10 wt%) into the BisGMA/TEGDMA dental resins or impregnation of small mass fractions of the HAP nanofibers (2 wt% or 3 wt%) into the dental composites can substantially improve the biaxial flexural strength of the resulting dental resins and composites. A percolation threshold of HAP nanofibers, beyond which more nanofibers will no longer further increase the mechanical properties of dental composites containing HAP nanofibers, was observed for the dental composites with or without silica microparticle filler. Our mechanical testing and fractographic analysis indicated that the relatively good dispersion of HAP nanofibers at low mass fraction is the key reason for the significantly improved biaxial flexural strength, while higher mass fraction of HAP nanofibers tends to lead to bundles that cannot effectively reinforce the dental resins or composites and may even serve as defects and thus degrade the resulting dental resin and composite mechanical properties. SIGNIFICANCE The incorporation of small mass fraction of HAP nanofibers with good dispersion can improve the mechanical property of dental resins and dental composites.
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Affiliation(s)
- Liang Chen
- Department of Mechanical and Aerospace Engineering, University of Missouri-Columbia, Columbia, MO 65211, United States
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Garoushi S, Lassila LVJ, Vallittu PK. Influence of nanometer scale particulate fillers on some properties of microfilled composite resin. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:1645-1651. [PMID: 21611793 DOI: 10.1007/s10856-011-4352-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Accepted: 05/16/2011] [Indexed: 05/30/2023]
Abstract
The aim of this study was to evaluate the effect of different weight fractions of nanometer sized particulate filler on properties of microfilled composite resin. Composite resin was prepared by mixing 33 wt% of resin matrix to the 67 wt% of silane treated microfine silica particulate fillers with various fractions of nanometer sized fillers (0, 10, 15, 20, 30 wt%) using a high speed mixing machine. Test specimens made of the composites were tested with a three-point bending test with a speed of 1.0 mm/min until fracture. Surface microhardess (Vicker's microhardness) was also determined. The volumetric shrinkage in percent was calculated as a buoyancy change in distilled water by means of the Archimedes principle. The degree of monomer conversion (DC%) of the experimental composites containing different nanofiller fractions was measured using FTIR spectroscopy. Surface roughness (Ra) was determined using a surface profilometer. Nanowear measurements were carried out using a nanoindentation device. The water uptake of specimens was also measured. Parameters were statistically analysed by ANOVA (P < 0.05). The group without nanofillers showed the highest flexural strength and modulus, DC% and Ra value. The group with 30% nanofillers had the highest water uptake and volumetric shrinkage. No significant difference was found in Vicker's microhardness and the nanowear of the composites. The plain microfilled composite demonstrated superior properties compared to the composites loaded with nanofillers with the exception of surface roughness.
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Affiliation(s)
- Sufyan Garoushi
- Department of Biomaterials Science, Institute of Dentistry and BioCity Turku Biomaterials Research Program, University of Turku, Turku, Finland.
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Cramer N, Stansbury J, Bowman C. Recent advances and developments in composite dental restorative materials. J Dent Res 2011; 90:402-16. [PMID: 20924063 PMCID: PMC3144137 DOI: 10.1177/0022034510381263] [Citation(s) in RCA: 354] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 07/01/2010] [Accepted: 07/15/2010] [Indexed: 11/16/2022] Open
Abstract
Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material properties. These materials are presently limited by shrinkage and polymerization-induced shrinkage stress, limited toughness, the presence of unreacted monomer that remains following the polymerization, and several other factors. Fortunately, these materials have been the focus of a great deal of research in recent years with the goal of improving restoration performance by changing the initiation system, monomers, and fillers and their coupling agents, and by developing novel polymerization strategies. Here, we review the general characteristics of the polymerization reaction and recent approaches that have been taken to improve composite restorative performance.
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Affiliation(s)
- N.B. Cramer
- Dept. of Chemical & Biological Engineering, University of Colorado, UCB 424, Boulder, CO 80309, USA
| | - J.W. Stansbury
- Dept. of Chemical & Biological Engineering, University of Colorado, UCB 424, Boulder, CO 80309, USA
- Dept. of Craniofacial Biology, School of Dental Medicine, University of Colorado Denver, Aurora, CO 80045, USA
| | - C.N. Bowman
- Dept. of Chemical & Biological Engineering, University of Colorado, UCB 424, Boulder, CO 80309, USA
- Dept. of Craniofacial Biology, School of Dental Medicine, University of Colorado Denver, Aurora, CO 80045, USA
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Control of polymerization shrinkage and stress in nanogel-modified monomer and composite materials. Dent Mater 2011; 27:509-19. [PMID: 21388669 DOI: 10.1016/j.dental.2011.01.006] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 12/02/2010] [Accepted: 01/17/2011] [Indexed: 11/21/2022]
Abstract
OBJECTIVES This study demonstrates the effects of nano-scale prepolymer particles as additives to model dental monomer and composite formulations. METHODS Discrete nanogel particles were prepared by solution photopolymerization of isobornyl methacrylate and urethane dimethacrylate in the presence of a chain transfer agent, which also provided a means to attach reactive groups to the prepolymer. Nanogel was added to triethylene glycol dimethacrylate (TEGDMA) in increments between 5 and 40 wt% with resin viscosity, reaction kinetics, shrinkage, mechanical properties, stress and optical properties evaluated. Maximum loading of barium glass filler was determined as a function of nanogel content and composites with varied nanogel content but uniform filler loading were compared in terms of consistency, conversion, shrinkage and mechanical properties. RESULTS High conversion, high molecular weight internally crosslinked and cyclized nanogel prepolymer was efficiently prepared and redispersed into TEGDMA with an exponential rise in viscosity accompanying nanogel content. Nanogel addition at any level produced no deleterious effects on reaction kinetics, conversion or mechanical properties, as long as reactive nanogels were used. A reduction in polymerization shrinkage and stress was achieved in proportion to nanogel content. Even at high nanogel concentrations, the maximum loading of glass filler was only marginally reduced relative to the control and high strength composite materials with low shrinkage were obtained. SIGNIFICANCE The use of reactive nanogels offers a versatile platform from which resin and composite handling properties can be adjusted while the polymerization shrinkage and stress development that challenge the adhesive bonding of dental restoratives are controllably reduced.
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Abstract
Nanotechnology, or nanoscience, refers to the research and development of an applied science at the atomic, molecular, or macromolecular levels (i.e. molecular engineering, manufacturing). The prefix "nano" is defined as a unit of measurement in which the characteristic dimension is one billionth of a unit. Although the nanoscale is small in size, its potential is vast. As nanotechnology expands in other fields, clinicians, scientists, and manufacturers are working to discover the uses and advances in biomedical sciences. Applications of nanotechnology in medical and dental fields have only approached the horizon with opportunities and possibilities for the future that can only be limited by our imagination. This paper provides an early glimpse of nanotechnology applications in medicine and dentistry to illustrate their potentially far-reaching impacts on clinical practice. It also narrates the safety issues concerning nanotechnology applications.
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Affiliation(s)
- Jyoti Gupta
- Department of Periodontics, Dr H.S.J. Institute of Dental Sciences and Research, Chandigarh, India
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Durrani OK, Bashir U, Arshad N. Fabrication and evaluation of Bis-GMA/TEGDMA resin with various amounts of silane-coated silica for orthodontic use. Eur J Orthod 2011; 34:62-6. [PMID: 21292732 DOI: 10.1093/ejo/cjq159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The objective of this research was to fabricate a composite with an optimum filler level in a bisphenol-A-glycidyldimethacrylate (Bis-GMA) triethylene glycidal dimethacrylate (TEGDMA) resin for bonding of metallic orthodontic brackets to achieve the best handling characteristics with optimum bond strength and without compromising the mechanical properties of the adhesive. One-hundred and sixty extracted human premolars free of any detectable pathology or buccal surface alterations were collected and divided into four groups. In group 1 (control), the teeth were bonded with stainless steel brackets using Transbond XT. In groups 2, 3, and 4, the teeth were bonded with metal brackets using a Bis-GMA/TEGDMA resin with 80, 60, and 20 per cent by weight silane-coated silica of a spherical shape with a mean size of 0.01 μm. Shear bond strength (SBS) of the composites was determined and the adhesive remnant index (ARI) and enamel fracture post-debonding were assessed. According to one-way analysis of variance and Tukey's honestly significant difference (HSD) multiple comparison tests, the SBS of group 4 (10.54 MPa) was considerably less than that of groups 1 (26.1 MPa), 2 (25.5 MPa), and 3 (24.6 MPa). Chi-square analysis revealed that there was an insignificant difference in the incidence of enamel fracture between groups 1 and 2, while a significant difference was present between groups 1 and 2 and 3 and 4. An insignificant difference was also observed in the location of the adhesive failure between the four groups. While all the bonding adhesives tested can be safely used for bonding of brackets, 60 per cent filled Bis-GMA/TEGDMA was superior clinically due to its ease of handling and superior bond strength.
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Affiliation(s)
- Owais Khalid Durrani
- Department of Orthodontics, Riphah International University, Islamabad, Pakistan.
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Biodegradable Nanofibers-Reinforced Microfibrous Composite Scaffolds for Bone Tissue Engineering. Tissue Eng Part A 2010; 16:3599-609. [DOI: 10.1089/ten.tea.2009.0779] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Xu X, Guo G, Fan Y. Fabrication and characterization of dense zirconia and zirconia-silica ceramic nanofibers. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2010; 10:5672-9. [PMID: 21133090 PMCID: PMC3181101 DOI: 10.1166/jnn.2010.2441] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The objective of this study was to prepare dense zirconia-yttria (ZY), zirconia-silica (ZS) and zirconia-yttria-silica (ZYS) nanofibers as reinforcing elements for dental composites. Zirconium (IV) propoxide, yttrium nitrate hexahydrate, and tetraethyl orthosilicate (TEOS) were used as precursors for the preparation of zirconia, yttria, and silica sols. A small amount (1-1.5 wt%) of polyethylene oxide (PEO) was used as a carry polymer. The sols were preheated at 70 degrees C before electrospinning and their viscosity was measured with a viscometer at different heating time. The gel point was determined by viscosity-time (eta-t) curve. The ZY, ZS and ZYS gel nanofibers were prepared using a special reactive electrospinning device under the conditions near the gel point. The as-prepared gel nanofibers had diameters between 200 and 400 nm. Dense (nonporous) ceramic nanofibers of zirconia-yttria (96/4), zirconia-silica (80/20) and zirconia-yttria-silica (76.8/3.2/20) with diameter of 100-300 nm were obtained by subsequent calcinations at different temperatures. The gel and ceramic nanofibers obtained were characterized by scanning electron microscope (SEM), high-resolution field-emission scanning electron microscope (FE-SEM), thermogravimetric analyzer (TGA), differential scanning calorimeter (DSC), Fourier transform infrared spectrometer (FT-IR), and X-ray diffraction (XRD). SEM micrograph revealed that ceramic ZY nanofibers had grained structure, while ceramic ZS and ZYS nanofibers had smooth surfaces, both showing no visible porosity under FE-SEM. Complete removal of the polymer PEO was confirmed by TGA/DSC and FT-IR. The formation of tetragonal phase of zirconia and amorphous silica was proved by XRD. In conclusion, dense zirconia-based ceramic nanofibers can be fabricated using the new reactive sol-gel electrospinning technology with minimum organic polymer additives.
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Affiliation(s)
- Xiaoming Xu
- Department of Comprehensive Dentistry and Biomaterials, Louisiana State University Health Science Center, School of Dentistry, Box 137, 1100 Florida Avenue, New Orleans, LA 70119, USA
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Xu HHK, Weir MD, Sun L, Moreau JL, Takagi S, Chow LC, Antonucci JM. Strong nanocomposites with Ca, PO(4), and F release for caries inhibition. J Dent Res 2010; 89:19-28. [PMID: 19948941 DOI: 10.1177/0022034509351969] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
This article reviews recent studies on: (1) the synthesis of novel calcium phosphate and calcium fluoride nanoparticles and their incorporation into dental resins to develop nanocomposites; (2) the effects of key microstructural parameters on Ca, PO(4), and F ion release from nanocomposites, including the effects of nanofiller volume fraction, particle size, and silanization; and (3) mechanical properties of nanocomposites, including water-aging effects, flexural strength, fracture toughness, and three-body wear. This article demonstrates that a major advantage of using the new nanoparticles is that high levels of Ca, PO(4), and F release can be achieved at low filler levels in the resin, because of the high surface areas of the nanoparticles. This leaves room in the resin for substantial reinforcement fillers. The combination of releasing nanofillers with stable and strong reinforcing fillers is promising to yield a nanocomposite with both stress-bearing and caries-inhibiting capabilities, a combination not yet available in current materials.
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Affiliation(s)
- H H K Xu
- Department of Endodontics, Prosthodontics and Operative Dentistry, University of Maryland Dental School, 650 West Baltimore Street, Baltimore, MD 21201, USA.
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Lassila LVJ, Garoushi S, Tanner J, Vallittu PK, Söderling E. Adherence of Streptococcus mutans to Fiber-Reinforced Filling Composite and Conventional Restorative Materials. Open Dent J 2009; 3:227-32. [PMID: 20148170 PMCID: PMC2817876 DOI: 10.2174/1874210600903010227] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Revised: 04/04/2009] [Accepted: 09/04/2009] [Indexed: 11/22/2022] Open
Abstract
Objectives. The aim was to investigate the adhesion of Streptococcus mutans (S. mutans) to a short glass fibers reinforced semi-IPN polymer matrix composite resin. The effect of surface roughness on adhesion was also studied. For comparison, different commercial restorative materials were also evaluated. Materials and Methods. Experimental composite FC resin was prepared by mixing 22.5 wt% of short E-glass fibers, 22.5 wt% of IPN-resin and 55 wt% of silane treated silica fillers using high speed mixing machine. Three direct composite resins (Z250, Grandio and Nulite), resin-modified glass ionomers (Fuji II LC), amalgam (ANA 2000), fiber-reinforced composite (FRC) (everStick and Ribbond), and pre-fabricated ceramic filling insert (Cerana class 1) were tested in this study. Enamel and dentin were used as controls. The specimens (n=3/group) with or without saliva were incubated in a suspension of S. mutans allowing initial adhesion to occur. For the enumeration of cells on the disc surfaces as colony forming units (CFU) the vials with the microbe samples were thoroughly Vortex-treated and after serial dilutions grown anaerobically for 2 days at +37°C on Mitis salivarius agars (Difco) containing bacitracin. Bacterial adhesion was also evaluated by using scanning electron microscopy. Surface roughness (Ra) of the materials was also determined using a surface profilometer. All results were statistically analyzed with one-way analysis of variance (ANOVA). Results. Composite FC resin and other commercial restorative materials showed similar adhesion of S. mutans, while adhesion to dentin and enamel was significantly higher (p<0.05). Surface roughness had no effect on bacterial adhesion. Saliva coating significantly decreased the adhesion for all materials (p<0.05). Composite FC resin had a significantly higher Ra value than control groups (p<0.05). Conclusions. Short fiber-reinforced composite with semi-IPN polymer matrix revealed similar S. mutans adhesion than commercial restorative materials.
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Affiliation(s)
- Lippo V J Lassila
- Department of Prosthetic Dentistry & Biomaterials Science, Institute of Dentistry, University of Turku, Turku, Finland
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Saunders SA. Current practicality of nanotechnology in dentistry. Part 1: Focus on nanocomposite restoratives and biomimetics. Clin Cosmet Investig Dent 2009; 1:47-61. [PMID: 23674905 PMCID: PMC3652345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
First described in 1959 by physicist Richard P Feynman, who saw it as an unavoidable development in the progress of science, nanotechnology has been part of mainstream scientific theory with potential medical and dental applications since the early 1990s. Nanoparticles, nanospheres, nanorods, nanotubes, nanofibers, dendrimers and other nanostructures have been studied for various applications to biologic tissues and systems. While many layers of nanotechnologic capability have been envisioned for oral health in the last decade (eg, oral hygiene maintenance, local anesthesia, even whole-tooth replacement), few of these applications have been developed. Part 1 of a three-part series reviews the current clinical utility of nanotechnology's most tangible contribution to dentistry to date: the restoration of tooth structure with nanocomposites. Characterized by filler-particle sizes of ≤100 nm, these materials can offer esthetic and strength advantages over conventional microfilled and hybrid resin-based composite (RBC) systems, primarily in terms of smoothness, polishability and precision of shade characterization, plus flexural strength and microhardness similar to those of the better-performing posterior RBCs. Available comparative data for nanocomposites and organically-modified ceramic (Ormocer(®)) restoratives are also reviewed. Finally, plausible "next-phase" trends in current nanorestorative research are judiciously examined, including 1) calcium-, phosphate-, and fluoride-ion-releasing nanocomposites for anticaries applications and 2) restorative systems based on biomimetic emulation of the nanomolecular assembly processes inherent in dental enamel formation using nanorods, nanospheres, and recombinant amelogenins.
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Affiliation(s)
- Scott A Saunders
- Correspondence: Scott A Saunders, Principal, MirrorMonitor Creativity, 1014 Andrew Way, Royersford, PA 19468-3134, USA, Tel +1 610 948 2001, Fax +1 610 948 2001, Email
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Buruiana T, Buruiana EC, Melinte V, Colceriu A, Moldovan M. Urethane dimethacrylate oligomers for dental composite matrix: Synthesis and properties. POLYM ENG SCI 2009. [DOI: 10.1002/pen.21351] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Buruiana T, Melinte V, Stroea L, Buruiana EC. Urethane Dimethacrylates with Carboxylic Groups as Potential Dental Monomers. Synthesis and Properties. Polym J 2009. [DOI: 10.1295/polymj.pj2009131] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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