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Elshenawy EA, El-Ebiary MA, Kenawy ER, El-Olimy GA. Modification of glass-ionomer cement properties by quaternized chitosan-coated nanoparticles. Odontology 2023; 111:328-341. [PMID: 36070157 PMCID: PMC10020264 DOI: 10.1007/s10266-022-00738-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 08/24/2022] [Indexed: 10/14/2022]
Abstract
Glass ionomers (GICs), because of their qualities, are in a good position to be modified to resist masticatory stresses as permanent posterior restoration and prevent recurrent caries. The purpose of the present study was to evaluate the effect of adding quaternized chitosan-coated mesoporous silica nanoparticles (HTCC@MSNs) to conventional GIC on its mechanical properties, antimicrobial activity and fluoride release and the effect of 1- and 3-month water aging on the studied properties. HTCC@MSNs was synthesized, added to commercially available conventional GIC at 1%, 3%, and 5% by weight forming three experimental groups and compared with plain GIC as a control group. Flexural strength, modulus, Vickers microhardness and wear volumes were evaluated. Antibacterial activity was tested against Streptococcus mutans and fluoride release in de-ionized water was measured. All properties were evaluated before and after one- and three-month aging (n = 10 specimens per test/per time). Two-way ANOVA was used for statistical analysis. Characterization confirmed successful preparation of HTCC@MSNs. The flexural strength, modulus, hardness and wear resistance of the GICs improved significantly by adding 1-3% HTCC@MSNs, while 5% HTCC@MSNs group showed no significant difference compared to control group. Bacterial inhibition zones and fluoride release increased proportionally to the amount of filler added. Mechanical properties were improved by artificial aging. Fluoride release values, and bacterial inhibition zones decreased with aging for all groups. HTCC@MSNs as a filler with the optimized proportion provides strengthening and antibacterial effect. In addition, aging is an important factor to be considered in evaluating experimental fillers.
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Affiliation(s)
- Enas A Elshenawy
- Dental Biomaterials Department, Faculty of Dentistry, Tanta University, Tanta, 31773, Egypt.
| | - Manal Ahmed El-Ebiary
- Dental Biomaterials Department, Faculty of Dentistry, Tanta University, Tanta, 31773, Egypt
| | - El-Refaie Kenawy
- Chemistry Department, Faculty of Science, Tanta University, Tanta, 31111, Egypt
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de Lima Navarro MF, Pascotto RC, Borges AFS, Soares CJ, Raggio DP, Rios D, Bresciani E, Molina GF, Ngo HC, Miletić I, Frencken J, Wang L, Menezes-Silva R, Puppin-Rontani RM, de Carvalho RM, Gurgan S, Leal SC, Tüzüner T, Fagundes TC, Nicholson JW, Sidhu SK. Consensus on glass-ionomer cement thresholds for restorative indications. J Dent 2021; 107:103609. [PMID: 33610589 DOI: 10.1016/j.jdent.2021.103609] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 02/14/2021] [Accepted: 02/15/2021] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVE The aim of this paper is to present the results of a consensus meeting on the threshold property requirements for the clinical use of conventional glass-ionomer cements (GICs) for restorative indications. METHODS Twenty-one experts on GICs evaluated the results of tests on mechanical and optical properties of 18 different brands of restorative GICs: Bioglass R [B], Chemfil Rock [CR], Equia Forte [EF], Gold Label 2 [GL2], Gold Label 9 [GL9], Glass Ionomer Cement II [GI], Ionglass [IG], Ion Z [IZ], Ionomaster [IM], Ionofil Plus [IP], Ionostar Plus [IS], Ketac Molar Easymix [KM], Magic Glass [MG], Maxxion R [MA], Riva Self Cure [R], Vidrion R [V], Vitro Fil [VF] and Vitro Molar [VM]. All experiments were carried out by a team of researchers from Brazil and England following strict protocols, under the same laboratory conditions throughout, and maintaining data integrity. RESULTS There was consensus on: determining as primary properties of the material: compressive strength, microhardness, acid erosion and fluoride release, and as secondary properties: contrast ratio and translucency parameter, in order to rank the materials. Seven brands were below the thresholds for restorative indications: IZ, IM, IG, MA, VF, B and MG. CONCLUSIONS Based on the primary properties adopted as being essential for restorative indications, the conventional restorative GICs that met the thresholds and could be considered suitable as long-term restorative materials were: EF, GI, GL9, KM, IP, GL2, IS, CR, V, VM and R. A decision-making process to select the best GIC must also include results from clinical trials. CLINICAL SIGNIFICANCE This study provides a ranking of GICs that could be considered suitable as long-term restorative materials based on their main properties.
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Affiliation(s)
- Maria Fidela de Lima Navarro
- Department of Restorative Dentistry, Bauru School of Dentistry, University of São Paulo, Alameda Dr. Octávio Pinheiro Brisolla, 9-75 - Jardim Brasil, 17012-901, Bauru, Brazil.
| | - Renata Corrêa Pascotto
- Department of Restorative Dentistry, State University of Maringá, Av. Colombo, 5790 - Jd. Universitário, 87020-900, Maringá, Brazil
| | - Ana Flávia Sanches Borges
- Department of Restorative Dentistry, Bauru School of Dentistry, University of São Paulo, Alameda Dr. Octávio Pinheiro Brisolla, 9-75 - Jardim Brasil, 17012-901, Bauru, Brazil
| | - Carlos José Soares
- Department of Restorative Dentistry, Federal University of Uberlândia, Av. João Naves de Ávila, 2121 - Santa Mônica, 38408-100, Uberlândia, Brazil
| | - Daniela Prócida Raggio
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes, 2227 - Butantã, 05508-000, São Paulo, Brazil
| | - Daniela Rios
- Department of Restorative Dentistry, Bauru School of Dentistry, University of São Paulo, Alameda Dr. Octávio Pinheiro Brisolla, 9-75 - Jardim Brasil, 17012-901, Bauru, Brazil
| | - Eduardo Bresciani
- Institute of Science and Technology, State University of São Paulo, Av. Eng. Francisco José Longo, 777 - Jardim São Dimas, 12245-00, São José dos Campos, Brazil
| | | | - Hien Chi Ngo
- Dean and Head of School/Director of OHCWA, The University of Western Australia, 512, 17 Monash Avenue, Nedlands, WA 6009, Australia
| | - Ivana Miletić
- School of Dental Medicine, University of Zagreb, Gundulićeva ul. 5, 10000, Zagreb, Croatia
| | - Jo Frencken
- Department of Dentistry, Radboud University Medical Centre, Philips van Leydenlaan 25, 6525 EX, Nijmegen, the Netherlands
| | - Linda Wang
- Department of Restorative Dentistry, Bauru School of Dentistry, University of São Paulo, Alameda Dr. Octávio Pinheiro Brisolla, 9-75 - Jardim Brasil, 17012-901, Bauru, Brazil
| | - Rafael Menezes-Silva
- Department of Restorative Dentistry, Bauru School of Dentistry, University of São Paulo, Alameda Dr. Octávio Pinheiro Brisolla, 9-75 - Jardim Brasil, 17012-901, Bauru, Brazil
| | | | | | - Sevil Gurgan
- Department of Restorative Dentistry, Hacettepe University, 06800, Ankara, Turkey
| | | | | | - Ticiane Cestari Fagundes
- Araçatuba School of Dentistry, State University of São Paulo, Rua José Bonifácio, 1193, 16015-050, Araçatuba, Brazil
| | - John William Nicholson
- Bluefield Centre for Biomaterials, Unit 34, 67-68 Hatton Garden, Holborn, London EC1N 8JY, England, United Kingdom
| | - Sharanbir Kaur Sidhu
- Queen Mary University of London, Mile End Rd, Bethnal Green, London E1 4NS, England, United Kingdom
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Noori AJ, Kareem FA. The effect of magnesium oxide nanoparticles on the antibacterial and antibiofilm properties of glass-ionomer cement. Heliyon 2019; 5:e02568. [PMID: 31667407 PMCID: PMC6812241 DOI: 10.1016/j.heliyon.2019.e02568] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/17/2019] [Accepted: 09/30/2019] [Indexed: 10/28/2022] Open
Abstract
Objectives This study examined the antibacterial and antibiofilm properties of conventional glass-ionomer cement (GIC) modified by the addition of magnesium oxide (MgO) nanoparticles. Materials and methods MgO nanoparticles were characterised by XRD, FTIR, and SEM analysis and tested for its activity against Streptococcus mutans and Streptococcus sobrinus. MgO nanoparticles were incorporated into GIC powder (Ketac Molar Easymix) at different concentrations and the antibacterial and antibiofilm activity was evaluated using agar disk diffusion and biofilm-CFU counting assays. ANOVA and Tukey's post hoc tests were used for the analysis, and the level of significance was set at p < 0.05. Results MgO nanoparticles showed antibacterial activity against both microorganisms (MIC = 500 μg/ml and MBC = 1000 μg/ml). A significant difference in the zones of inhibition was detected (p < 0.005). The effect was evident in the 2.5% MgO nanoparticle modified GIC while the CFU counting biofilm assay showed the effect of the added nanoparticles from 1% with a significant difference between the tested material groups (p < 0.005). Conclusions The MgO nanoparticle modified GIC showed effective antibacterial and antibiofilm activity against two cariogenic microorganisms and could be considered for further development as a biocompatible antibacterial dental restorative cement.
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Affiliation(s)
- Arass Jalal Noori
- Department of Pedodontics, Orthodontics and Preventive Dentistry, College of Dentistry, University of Sulaimani, Sulaymaniyah, 46001, Iraq
| | - Fadil Abdullah Kareem
- Department of Pedodontics, Orthodontics and Preventive Dentistry, College of Dentistry, University of Sulaimani, Sulaymaniyah, 46001, Iraq
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Zilberman U, Hassan J, Leiboviz-Haviv S. Molar incisor hypomineralization and pre-eruptive intracoronal lesions in dentistry-diagnosis and treatment planning. World J Stomatol 2019; 7:20-27. [DOI: 10.5321/wjs.v7.i2.20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/14/2019] [Accepted: 01/28/2019] [Indexed: 02/06/2023] Open
Abstract
The aim of this study is to report the diagnostic features, prevalence, mineral content, clinical significance and treatment options of molar incisor hypomineralization (MIH) and pre-eruptive intracoronal lesions (PEIR), in order to minimize miss-treatment of primary and permanent teeth in young children. MIH was defined as the occurrence of hypomineralization of one up to four permanent first molars from a systemic origin and frequently associated with affected incisors. PEIR are lesions that are located in the occlusal portion of the crown of unerupted permanent or primary teeth. The prevalence of MIH was reported between 2.5%-40% in the permanent first molars and 0%-21.8% in primary second molars. PEIR was observed in 2%-8% of children, mainly in mandibular second premolars and second and third permanent molars. A number of possible causes for MIH were mentioned, including environmental changes, diet and genetics in prenatal and postnatal periods, but all are questionable. In PEIR, the resorption of the intracoronal dentine begins only after crown development is complete and is caused by giant cells resembling osteoclast observed histologically on the dentine surface close to the pulp. The mineral content in MIH is reduced in comparison to normal enamel and dependent on the severity of the lesion. In PEIR the resorbed surface of enamel showed less mineral content. The hypomineralized enamel in MIH is not suitable for restorations with amalgam or composite materials, and the best material should be based on remineralization material like glass-ionomers. Similar, the resorbed dentin surface in PEIR should be covered by the biocompatible and re-mineralizing glass-ionomer cement.
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Affiliation(s)
- Uri Zilberman
- Pediatric Dental Clinic, Barzilai Medical University Center, Ashkelon 7830604, Israel
| | - Jomanna Hassan
- Pediatric Dental Clinic, Barzilai Medical University Center, Ashkelon 7830604, Israel
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de Oliveira BMB, Agostini IE, Baesso ML, Menezes-Silva R, Borges AFS, Navarro MFL, Nicholson JW, Sidhu SK, Pascotto RC. Influence of external energy sources on the dynamic setting process of glass-ionomer cements. Dent Mater 2019; 35:450-456. [PMID: 30709613 DOI: 10.1016/j.dental.2019.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 11/02/2018] [Accepted: 01/03/2019] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To evaluate the influence of external energy sources on the dynamic setting process of glass-ionomer restorative materials. METHODS Eighteen brands of GIC were studied: Bioglass R (Biodinâmica; G1), Chemfil Rock (Dentsply; G2), Equia Forte (GC; G3), Gold Label 2 (GC; G4), Gold Label 9 (GC; G5), Glass Ionomer Cement Type II - (Shofu; G6), Ionglass R (Maquira; G7), Ion Z (FGM; G8), Ionomaster (Wilcos; G9), Ionofil Plus (Voco; G10), Ionostar Plus (Voco; G11), Ketac Molar easymix (3M ESPE; G12), Magic Glass R (Vigodent; G13), Maxxion R (FGM; G14), Riva Self Cure (SDI; G15), Vidrion R (SS White; G16), Vitro Fil R (Nova DFL; G17) and Vitro Molar (Nova DFL; G18). LED, halogen light or ultrasound (n=20 for each set) applied for 30s was used to activate setting, and a control group of each material was allowed to set without activation. Samples were analyzed by FTIR spectroscopy using the ratio of intensities of bands at 1637cm-1 (carboxylate) and 1720cm-1 (carbonyl) as a function of time. Means and standard deviations were subjected to ANOVA and Tukey tests (p<0.05). RESULTS All three activation modes significantly reduced the time at which the carboxylate content became stable in G2, G4, G5, G6, G8, G10, G14, G16, G17 and G18. By contrast, in G1, G7, G12 and G15 no activation source had any significant effect (p>0.05). SIGNIFICANCE External activation sources, namely LED, halogen light and ultrasound, typically but not always increase the setting rate of restorative GICs.
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Affiliation(s)
- Bruna M B de Oliveira
- Department of Dentistry, State University of Maringa, Av. Mandacaru 1550, 87080-000 Maringá, PR, Brazil
| | - Izabelle E Agostini
- Department of Dentistry, State University of Maringa, Av. Mandacaru 1550, 87080-000 Maringá, PR, Brazil
| | - Mauro L Baesso
- Department of Physics, State University of Maringa, Av. Colombo 5790, 87020-900 Maringá, PR, Brazil
| | - Rafael Menezes-Silva
- Department of Operative Dentistry, Endondontics and Dental Materials, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901 Bauru, SP, Brazil
| | - Ana Flávia S Borges
- Department of Operative Dentistry, Endondontics and Dental Materials, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901 Bauru, SP, Brazil
| | - Maria Fidela L Navarro
- Department of Operative Dentistry, Endondontics and Dental Materials, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901 Bauru, SP, Brazil
| | - John W Nicholson
- Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK
| | - Sharanbir K Sidhu
- Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK
| | - Renata C Pascotto
- Department of Dentistry, State University of Maringa, Av. Mandacaru 1550, 87080-000 Maringá, PR, Brazil.
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Menezes-Silva R, de Oliveira BMB, Fernandes PHM, Shimohara LY, Pereira FV, Borges AFS, Buzalaf MAR, Pascotto RC, Sidhu SK, de Lima Navarro MF. Effects of the reinforced cellulose nanocrystals on glass-ionomer cements. Dent Mater 2019; 35:564-573. [PMID: 30711272 DOI: 10.1016/j.dental.2019.01.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/31/2018] [Accepted: 01/11/2019] [Indexed: 10/27/2022]
Abstract
OBJECTIVE Glass-ionomer cements (GICs) modified with cellulose nanocrystals (CNs) were characterized and evaluated for compressive strength (CS), diametral tensile strength (DTS) and fluoride release (F-). METHODS Commercially available GICs (Maxxion, Vidrion R, Vitro Molar, Ketac Molar Easy Mix and Fuji Gold Label 9) were reinforced with CNs (0.2% by weight). The microstructure of CNs and of CN-modified GICs were evaluated by transmission electron microscopy (TEM) and by scanning electron microscopy (SEM) while chemical characterization was by Fourier transform infrared spectroscopy (FTIR). Ten specimens each of the unmodified (control) and CN-modified materials (test materials) were prepared for CS and DTS testing. For the fluoride release evaluation, separate specimens (n=10) of each test and control material were made. The results obtained were submitted to the t-test (p<0.05). RESULTS The CN reinforcement significantly improved the mechanical properties and significantly increased the F- release of all GICs (p<0.05). The GICs with CNs showed a fibrillar aggregate of nanoparticles interspersed in the matrix. The compounds with CNs showed a higher amount of C compared to the controls due to the organic nature of the CNs. It was not possible to identify by FTIR any chemical bond difference in the compounds formed when nanofibers were inserted in the GICs. SIGNIFICANCE Modification of GICs with CNs appears to produce promising restorative materials.
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Affiliation(s)
- Rafael Menezes-Silva
- Department of Dental Materials, Endodontics and Operative Dentistry, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901, Bauru, SP, Brazil.
| | | | - Paulo Henrique Martins Fernandes
- Department of Dental Materials, Endodontics and Operative Dentistry, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901, Bauru, SP, Brazil
| | - Lívia Yukari Shimohara
- Department of Dental Materials, Endodontics and Operative Dentistry, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901, Bauru, SP, Brazil
| | - Fabiano Vargas Pereira
- Department of Chemistry, Federal University of Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, MG, Brazil
| | - Ana Flávia Sanches Borges
- Department of Dental Materials, Endodontics and Operative Dentistry, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901, Bauru, SP, Brazil
| | - Marília Afonso Rabelo Buzalaf
- Department of Biological Sciences, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901, Bauru, SP, Brazil
| | - Renata Corrêa Pascotto
- Department of Dentistry, State University of Maringa, Av. Mandacaru, 1550, 87080-000, Maringá, PR, Brazil
| | - Sharanbir K Sidhu
- Institute of Dentistry, Barts & The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London, E1 2AD, UK
| | - Maria Fidela de Lima Navarro
- Department of Dental Materials, Endodontics and Operative Dentistry, Bauru School of Dentistry-FOB-USP, Al. Octávio Pinheiro Brisolla, 9-75, 17012-901, Bauru, SP, Brazil
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Webman M, Mulki E, Roldan R, Arevalo O, Roberts JF, Garcia-Godoy F. A Retrospective Study of the 3-Year Survival Rate of Resin-Modified Glass-Ionomer Cement Class II Restorations in Primary Molars. J Clin Pediatr Dent 2016; 40:8-13. [PMID: 26696100 DOI: 10.17796/1053-4628-40.1.8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To determine the three-year survival rate of Class II resin-modified glass-ionomer cement (RMGIC), Vitremer, restorations in primary molars and to compare these results with measurements of survival of Class II restorations of standard restorative materials. STUDY DESIGN Data on Class II restorations placed in primary molars during a six-year period were collected through a chart review and radiographic evaluation in the office of a board-certified pediatric dentist. A radiograph showing that the restoration was intact was required at least 3 years after placement to qualify as successful. If no radiograph existed, the restoration was excluded. If the restoration was not found to be intact radiographically or was charted as having been replaced before three years it was recorded as a failure. The results of this study were then compared to other standard restorative materials using normalized annual failure rates. RESULTS Of the 1,231 Class II resinmodified glass-ionomer cement restorations placed over six years 427 met the inclusion criteria. There was a 97.42% survival rate for a 3-year period equivalent to an annual failure rate of 0.86%. CONCLUSIONS A novel approach comparing materials showed that in this study Vitremer compared very favorably to previously published success rates of other standard restorative materials (amalgam, composite, stainless steel crown, compomer) and other RMGIC studies.
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Caldeira EM, Izquierdo ADM, Giacomet F, Sant'Anna EF, Ruellas ACDO. The influence of protective varnish on the integrity of orthodontic cements. Dental Press J Orthod 2013; 18:45-50. [PMID: 24351149 DOI: 10.1590/s2176-94512013000600008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE The aim of the present study was to assess the influence of saliva contamination over the structural strength and integrity of conventional glass-ionomer cements used for cementing orthodontic bands in the absence and presence of a surface-protecting varnish. METHODS 48 samples were prepared by inserting 3 types of glass-ionomer cements into standardized metallic matrixes with 10 mm of diameter and 2 mm of depth. The cements used were: Meron (VOCO), Ketac-Cem (3M ESPE) and Vidrion C (DFL), all of which comprised groups A, B and C, respectively. Subgroups A1, B1 and C1 comprised samples with no surface protection, whereas subgroups A2, B2 and C2 comprised samples of which surface was coated with Cavitine varnish (SS White), after cement manipulation and application, in order to protect the cement applied. All samples were stored in artificial saliva for 24 hours at 37°C. A Vickers diamond micro-durometer was used to produce indentations on the non-treated group (non-varnished) and the treated group (varnished). RESULTS Varnished materials had significantly higher microhardness values in comparison to non-varnished materials. Ketac-Cem had the highest microhardness value among the varnished materials. CONCLUSIONS Varnish application is necessary to preserve the cement and avoid enamel decalcification. Glass-ionomer cements should be protected in order to fully keep their properties, thus contributing to dental health during orthodontic treatment.
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