Orthodontic Brackets Research Articles

Shear Bond Strength of Orthodontic Brackets Bonded with Thermo-Cured Glass-Based Materials-An In Vitro Study.

The results of orthodontic therapy largely depend, among other factors, on the preparation of the tooth enamel itself and the choice of material used to bond orthodontic brackets. The aim of this in vitro study was to determine the shear bond strength (SBS) and adhesive remnant index (ARI) score of thermo-cured glass-ionomers on different pretreated enamel, in comparison with the commonly used composite cement. Three commercially available nano-ionomer or highly viscous glass-ionomer cements (EQUIA Forte® Fil, EQUIA Fil, Ketac Universal) and two types of compo-sites (Heliosit Orthodontic, ConTec Go!) were investigated in this study. The research involved two hundred human premolars. The teeth were cleaned and polished, then randomly divided into five groups according to the enamel preparation method and the type of material. The enamel was treated in three different ways: polyacrylic acid, phosphoric acid, 5% NaOCl + etching with phosphoric acid, and a control group without treatment. Glass-ionomer cement was thermo-cured with heat from a polymerization unit during setting. Statistical analysis was performed using a Chi-square test and one-way ANOVA for independent samples. Spearman's Rho correlation coefficient was used to examine the relationship. Regardless of the material type, the results indicated that the weakest bond between the bracket and tooth enamel was found in samples without enamel pretreatment. The majority of the materials stayed on the brackets in samples without enamel preparation, according to ARI scores. The study's findings demonstrated that the strength of the adhesion between the bracket and enamel is greatly influenced by enamel etching and glass-ionomer thermo-curing. Clinical investigations would be required to validate the outcomes.

Use of Electropolishing in Orthodontic Appliances: An Option to Reduce the Risk of Metal Hypersensitivity.

Electropolishing is a common treatment in the industry; however, how it behaves in the mouth and what benefits it can bring over metal dental attachments have not yet been established. Thus, the aim of this study was to determine the levels of corrosion, the released metal ions, and the changes in structural composition in metallic orthodontic appliances following electropolishing treatment. This study included 56 orthodontic brackets and 28 archwires. The samples were subjected to a pH cycle to simulate an oral environment. Using UV-Vis spectrophotometry, the release of metallic particles was evaluated, and using scanning electron microscopy, the structural and composition changes were evaluated. Groups were compared using Student's t-tests with a value of p ≤ 0.05. The cyclical pH solutions showed variations between groups and days (1, 3, 5, 7 and 15), reaching the highest acidification in the self-ligating brackets; the absorbance between solutions did not differ significantly. As seen from the SEM results, the experimental group showed minor irregularities compared with the control groups. The experimental brackets decreased in iron and increased in chromium after electropolishing, while for the NiTi archwires, they decreased in nickel. Therefore, electropolishing treatments in metallic orthodontic attachments improve their surface structure and corrosion resistance could reduce the risk of metal hypersensitivity, mainly from nickel.

Effect of Different Primers on the Shear Bond Strength of Orthodontic Brackets Bonded to Reinforced Polyetheretherketone (PEEK) Substrate.

This in vitro study assessed the effect of different primers on the shear bond strength (SBS) and adhesive remnant index (ARI) of orthodontic brackets bonded to reinforced polyetheretherketone (PEEK) substrate. A total of 40 specimens were randomly distributed to two groups based on the primer used for orthodontic bonding: group 1 (control)-Transbond XT adhesive with Visio.link primer and group 2 (test)-orthodontic adhesive (Transbond XT) with traditional orthodontic primer. After bonding, specimens were thermocycled followed by SBS testing and ARI scoring of debonded specimens. Data were analyzed using the unpaired independent t-test and the Chi-square test. Group 1 specimens showed significantly higher SBS values (21.38 ± 1.48 MPa) compared to group 2 specimens (18.63 ± 1.29 MPa) (p < 0.0001). Adhesive remnant index scores showed no significant variations in bond failure modes and distributions between groups. The SBS obtained by the tested primers exceeded the clinically recommended value. Consequently, there is a comparable clinical application for both tested primers in orthodontic bonding, especially the traditional orthodontic primer, where the availability of Visio.link in clinical practice is not ensured.

Comparative Evaluation of the Effect of Different Types of Bleaching Dentifrices on Shear Bond Strength of Orthodontic Metal Brackets Bonded by Conventional Composite to Human Teeth: An In Vitro Study.

This study aims to evaluate and compare the effect of different types of bleaching dentifrices on the shear bond strength of orthodontic metal brackets bonded by light-cured composite adhesive to human teeth. Forty-five human premolar teeth were randomly divided into three groups, receiving the following treatments: Group 1 (control group; teeth in this group were not bleached), Group 2 (teeth in this group were treated with active oxygen bleaching dentifrice), and Group 3 (teeth in this group were treated with peroxide bleaching dentifrice). Orthodontic brackets were bonded using a light-cured composite adhesive. A universal measuring device was used to assess the shear bond strength with a crosshead speed of 0.5 mm/min. One-way ANOVA, post hoc Tukey tests, and an independent t-test were used to analyse the data. There was a highly significant difference (p≤0.001) in the mean shear bond strength of orthodontic brackets bonded to untreated teeth as compared to teeth treated with bleaching dentifrice. There was no significant difference in the mean shear bond strength of orthodontic brackets bonded to teeth treated with peroxide bleaching dentifrice or active oxygen bleaching dentifrice. There was a significant reduction in the mean shear bond strength of orthodontic metal brackets when bonded to human teeth treated with bleaching dentifrices.

Evaluation of mechanical properties of nanoparticle-coated orthodontic brackets and wires

Evaluation of mechanical properties of nanoparticle-coated orthodontic brackets and wires

Enamel demineralization around Orthodontic brackets bonded with new bioactive composite (in-vitro study)

Enamel demineralization around Orthodontic brackets bonded with new bioactive composite (in-vitro study)

An Analysis Comparing the Precision of Stainless- Steel Orthodontic Brackets with 0.022-Inch Slots Offered by Various Manufacturers

An Analysis Comparing the Precision of Stainless- Steel Orthodontic Brackets with 0.022-Inch Slots Offered by Various Manufacturers

Performance of two laser motion modes versus conventional orthodontic ceramic brackets debonding technique on enamel surface topography.

The risk of enamel deterioration that frequently coexists with debonding of orthodontic teeth brackets elevates the mandate for finding an optimum approach for debonding them without harmful effects. This in-vitro study is intended to compare the effects of two different laser modes (scanning and circular) and a conventional method on the enamel surface after debonding orthodontic brackets. 66 extracted premolars were assigned into 3 groups. After that, light-cure composite resin was used to attach the ceramic brackets to the teeth. Amongst the test groups, Group I: specimens that were debonded using conventional debonding using pliers; Group 2: specimens that were debonded using Er, Cr: YSGG laser applications using the circular motion method; and Group 3: specimens that were debonded using Er, Cr: YSGG laser applications using the scanning motion method. Adhesive Remnant Index (ARI) assessment, intra-pulpal temperature increase, enamel surface roughness after polishing, and assessment of the microstructure of enamel were carried out with scanning electron microscopy. The gathered information was examined statistically. The conventional debonding method had a significantly higher proportion of adhesive remnant index (ARI) scores of 2 and 3 in comparison to the circular (p < .004) and scanning laser groups (p < .001). There was no significant difference in ARI scores between the circular and scanning laser groups (p > .05). Moreover, the circular and scanning laser debonding methods resulted in a significantly higher proportion of Enamel Surface Roughness (ESR) scores of 0 and a lower proportion of ESR scores of 3 compared to the conventional technique group (p < .001). However, there was no significant difference in ESR scores between the circular and scanning laser methods (p = .945). Lastly, the average intra-pulpal temperature was significantly higher in the circular laser group (1.9 ± 0.5 ) compared to the scanning laser group (0.9 ± 0.2) with p < .001. Er, Cr: YSGG laser irradiation is a tool that shows promise for debonding ceramic brackets with minimal harm to the enamel surface. The scanning laser technique is more desirable due to the lower intra-pulpal temperature increase.

Reduction of surface treatment time by combination of citric acid and ascorbic acid while restoring shear bond strength of metal brackets bonded to bleached enamel: a pilot study

BackgroundTo investigate the effect of a 50% ascorbic acid with 50% citric acid solution on the immediate shear bond strength (SBS) of metallic brackets after tooth bleaching. The enamel etching pattern and the required quantity of these combined acids as antioxidants following 35% hydrogen peroxide (HP) bleaching were also determined.MethodsThe stability of the solution at room temperature was assessed at various time intervals. Fifty teeth were randomly divided into five groups: non-bleached (G1), bleached then acid etched (G2), bleached followed by a 10-minute treatment with 10% sodium ascorbate and acid etched (G3), 5-minute treatment with 50% ascorbic acid (G4), and 5-minute treatment with a combination of 50% ascorbic acid and 50% citric acid (G5). Groups G2, G3, G4 and G5 were bleached by 35% HP gel for a total of 32 min. Acid etching in groups G1, G2, and G3 was performed using 37% phosphoric acid (Ormco®, Orange, CA, USA) for 15 s. In all groups, metal brackets were immediately bonded using Transbond™ XT primer and Transbond™ PLUS adhesive, with light curing for 40 s. The SBS was tested with a universal testing machine, and statistical analysis was conducted using one-way ANOVA followed by Tukey’s HSD test. The level of significance was set at p < 0.05 for all statistical tests.ResultsStability tests demonstrated that the combined acids remained effective for up to 21 days. Group G5 significantly increased the SBS of bleached teeth to the level of G1 (p < 0.05), while G3 did not achieve the same increase in SBS (p > 0.05). SEM analysis revealed enamel etching patterns similar to those of both control groups (G1 and G2). Kinetic studies at 6 min indicated that the antioxidation in G5 reacted 0.2 mmole lower than in G3 and G4.Conclusion5-minute application of the combined acids enhanced the SBS of bleached teeth comparable to unbleached teeth. The combined acids remain stable over two weeks, presenting a time-efficient, single-step solution for antioxidant application and enamel etching in orthodontic bracket bonding.

Evaluation of the Biocompatibility of Orthodontic Brackets and Wires: An In-Vitro Study.

Orthodontic treatment involves the use of various materials, including brackets and wires, which come into direct contact with oral tissues. Biocompatibility of these materials is crucial to ensure patient safety and treatment success. This study aims to evaluate the biocompatibility of orthodontic brackets and wires through an in-vitro investigation. Orthodontic brackets and wires commonly used in clinical practice were selected for this study. A series of in-vitro tests were conducted to assess the biocompatibility of these materials. Cell culture assays were performed to evaluate cytotoxicity, cell proliferation, and inflammatory response. In addition, scanning electron microscopy (SEM) was used to examine the surface characteristics of the materials. The cytotoxicity assays revealed minimal adverse effects on cell viability, with cell viability percentages ranging from 90% to 95% for all materials tested. Cell proliferation assays demonstrated similar rates of cell growth on the surfaces of both brackets and wires. SEM analysis indicated smooth surfaces with minimal irregularities, suggesting favorable biocompatibility. The findings of this in-vitro study suggest that the orthodontic brackets and wires examined exhibit satisfactory biocompatibility characteristics. Minimal cytotoxicity and favorable cell proliferation indicate that these materials are well suited for use in orthodontic treatment. Further clinical studies are warranted to validate these findings and ensure the safety and efficacy of orthodontic appliances in patient care.

Immediate orthodontic treatment after regeneration of periodontal intrabony defects: A long-term retrospective study

Background/purposeOrthodontic movement is often necessary for periodontally compromised patients to enhance esthetics, function, and long-term occlusal stability. However, the impact of orthodontic treatment immediately following the regeneration of intrabony defects on periodontal healing remains a topic of debate. The objective of this long-term case series study was to test the hypothesis that orthodontic treatment performed immediately after regenerative procedures for periodontal intrabony defects did not adversely affect periodontal healing. Materials and methodsThis case series study involved nine periodontally compromised subjects with a total of 17 intra-bony defects. Orthodontic brackets were applied immediately before surgery. Flaps were raised, and diseased roots were debrided. All intra-bony defects were filled with alloplastic bone grafts and covered with resorbable membranes, except for one defect treated with Emdogain. All patients initiated orthodontic treatment immediately after periodontal regenerative surgery. Clinical parameters, including probing depth, attachment level, and bone fill, were assessed at baseline and during final maintenance therapy. ResultsThe mean follow-up duration was 12.8 years. None of the 17 surgically regenerated teeth were lost. The mean reduction in probing depth was 3.94 mm (95% confidence level, 3.19–4.68; P < 0.001), with a mean clinical attachment gain of 3.47 mm (95% confidence level, 2.90–4.03; P < 0.001). The mean radiographic bone fill was 4.89 mm (P < 0.001). ConclusionBased on the findings of this long-term case study, it can be concluded that immediate orthodontic treatment does not adversely affect the maturation process of periodontal regeneration outcomes and can be maintained for more than ten years.

Investigation of mechanical properties, remineralization, antibacterial effect, and cellular toxicity of composite orthodontic adhesive combined with silver-containing nanostructured bioactive glass

BackgroundThe formation of white spots, which represent early carious lesions, is a major issue with fixed orthodontics. The addition of remineralizing agents to orthodontic adhesives may prevent the formation of white spots. The aim of this study was to produce a composite orthodontic adhesive combined with nano-bioactive glass-silver (nBG@Ag) for bracket bonding to enamel and to investigate its cytotoxicity, antimicrobial activity, remineralization capability, and bond strength.MethodsnBG@Ag was synthesized using the sol-gel method, and characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy with an attenuated total reflectance attachment (ATR-FTIR). The cytotoxicity test (MTT) and antimicrobial activity of adhesives containing 1%, 3%, and 5% (wt/wt) nBG@Ag were evaluated, and the shear bond strength of the adhesives was measured using a universal testing machine. Remineralization was assessed through microhardness testing with a Vickers microhardness tester and scanning electron microscopy (SEM). Statistical analyses were conducted using the Shapiro-Wilk test, Levene test, one-way ANOVA, Robust-Welch test, Tukey HSD method, and two-way ANOVA.ResultsThe biocompatibility of the adhesives was found to be high, as confirmed by the lack of significant differences in the cytotoxicity between the sample and control groups. Discs made from composites containing nBG@Ag exhibited a significant reduction in the growth of Streptococcus mutans (p < 0.05), and the antibacterial activity increased with higher percentages of nBG@Ag. The shear bond strength of the adhesives decreased significantly (p < 0.001) after the addition of nanoparticles, but it remained above the recommended value. The addition of nBG@Ag showed improvement in the microhardness of the teeth, although the differences in microhardness between the study groups were not statistically significant. The formation of hydroxyapatite deposits on the tooth surface was confirmed through SEM and energy-dispersive X-ray spectroscopy (EDX).ConclusionAdding nBG@Ag to orthodontic adhesives can be an effective approach to enhance antimicrobial activity and reduce enamel demineralization around the orthodontic brackets, without compromising biocompatibility and bond strength.

ИСПОЛЬЗОВАНИЕ ЦИФРОВЫХ ТЕХНОЛОГИЙ ПРИ РЕАБИЛИТАЦИИ ПАЦИЕНТОВ С ПЕРВИЧНОЙ АДЕНТИЕЙ

Abstract. Introduction. Number of patients with hypodontia has increased at orthodontic appointments. According to different authors, the frequency of tooth rudiments absence ranges from 2 % to 16.5 %. The highest rank is held by maxillary lateral incisors hypodontia. Due the increased patients’ aesthetic requirements, it is a difficult task, especially with the alveolar ridge bone deficiency. Treatment of such patients requires a multidisciplinary approach and the use of digital technology. The aim of the study is to improve the treatment effectiveness for patients with hypodontia, using digital planning, surgical templates, intraoral scanning, and the CAD/CAM modelling of metal-free screw-retained crowns on dental implants. Materials and Methods. The clinical study was performed in the dental office PreziDent (Cheboksary) in 2018-2023. The total number of patients was 24 people (female), aged 16 to 34 years. There were two groups (n=12). The first group patients had their missing teeth replaced using dental implantation without using any digital technology. In the second group, those with the use of digital technologies. Gingival condition of the dentition defect area was assessed: Severity of stippling phenomenon degree, density gingival margin adherence to the structural materials, vacuum capillary resistance by Kulazhenko, and Mülleman-Cowell bleeding index. SPSS 13.0 software package was used for the statistical processing of the results obtained. Results and Discussion. The first stage of treatment included orthodontic treatment, bracket placement and canine distalization. Some patients were fitted with orthodontic miniscrews in the subclavicular region. After creating gaps for the future lateral incisors, a surgical template was fabricated and dental implants were placed. Four months after implantation, the bracket system was removed and the implant temporary crowns were placed; six months later, CAD/CAM digital metal-free prosthetics were placed. Not a single case of implant loss was detected. An algorithm framework was developed for managing patients with maxillary lateral incisor hypodontia. Conclusions. Using computer programs for planning dental implantation and in navigation surgery allows installing dental implants most accurately and making digital metal-free prosthetic constructions by computer-aided modelling and manufacturing. Thus, the risk of complications is reduced and an effective functional and aesthetic state of dentoalveolar system is achieved in patients with primary anodontia.

Efficacy of peptide-based enamel coatings in the prevention of demineralization using fixed orthodontic brackets in a rat model

White spot lesions (WSLs) represent a prominent pathology encountered during orthodontic treatment, originating from enamel demineralization induced by the accumulation of bacterial biofilms. The previously developed bioinspired enamel coating form of self-assembling antimicrobial peptide D-GL13K exhibited antimicrobial activity and enhanced acid impermeability, offering a potential solution to prevent demineralization. The primary aim of this investigation is to assess the invivo anti-demineralization properties and biocompatibility of the D-GL13K coating. A rat model was developed to assess the antimicrobial enamel coating during fixed orthodontic treatment. The anti-demineralization efficacy attributed to the D-GL13K coating was evaluated by employing optical coherence tomography, Vickers microhardness testing, and scanning electron microscopy. The biocompatibility of the D-GL13K coating was investigated through histologic observations of vital organs and tissues using hematoxylin and eosin. The D-GL13K coating demonstrated significant anti-demineralization effects, evidenced by reduced demineralization depth analyzed through optical coherence tomography and enhanced Vickers hardness than in the noncoated control group, showcasing the coating's potential to protect teeth from WSLs. Scanning electron microscopy analysis further elucidated the diminished enamel damage observed in the group treated with D-GL13K. Importantly, histologic examination of vital organs and tissues using hematoxylin and eosin staining revealed no overt disparities between the D-GL13K coated group and the noncoated control group. The D-GL13K enamel coating demonstrated promising anti-demineralization and biocompatibility properties in a rat model, thereby suggesting its potential for averting WSLs after orthodontic interventions. Further research in human clinical settings is needed to evaluate the coating's long-term efficacy.

Evolution of the Antibacterial and Cellular Viability Effects of Silica-Hydroxyapatite Conjugated High Cerium Oxide Nanoparticles on Orthodontic Brackets

Evolution of the Antibacterial and Cellular Viability Effects of Silica-Hydroxyapatite Conjugated High Cerium Oxide Nanoparticles on Orthodontic Brackets

Mechanical and physical properties of attachments employed in clear aligner treatments. A critical appraisal

Clear aligners have become a viable option for orthodontic treatment. Unlike conventional orthodontic brackets, aligners are not directly bonded to teeth and thus, have a different application of forces. Attachments are a type of auxiliary for aligner treatment that creates points in which pressure can be applied on the tooth surface, acting to transmit forces from the aligner tray to the teeth. Currently, there is no consensus on what material should be used to fabricate attachments and how they behave clinically. Material and methods: The present study is a critical appraisal of data already published on the subject up to now: from 1784 records initially screened, 11 reports were included, mostly in vitro studies and with variable methodology. Results: Surface wear of attachments can vary from 9,6% to 100%. Attachment loss is roughly the same for upper and lower arches, but posterior teeth tend to present more losses. Patient-related variables might account for more failures than operator and material-related failures, but it has been shown that conventional composites might present better resistance, aligner fitting, and less surface wear. Conclusion: Clinicians might expect some degree of attachment surface wear and losses. Patient orientation and use of conventional composites with high filler content might reduce such failures and improve treatment results.

Enamel surface roughness following debonding resin clean up using high speed air-turbine and electric handpieces. In vitro study

BackgroundHigh speed electric handpieces have recently been growing in popularity among dental professionals. Advantages include smoother surface preparation and increased cutting efficiency.AimThe primary objective was to compare enamel surface roughness following resin cleanup after bracket debonding using highspeed air turbine versus electric handpiece. The secondary objective was to record the time needed for resin-clean up.MethodForty deidentified freshly extracted human premolars were cleaned and sectioned at the cement-enamel junction. The crowns were embedded in acrylic blocks. Enamel surface roughness parameters (Ra, Rz, Rp and Rv) were measured using a stylus profilometer. Brackets were bonded using a light-cure orthodontic adhesive and stored in distilled water for 24 h. Following bracket debonding, the specimens were randomly divided into 2 groups: First group: resin clean-up was carried out using a 12-fluted carbide bur mounted on a high-speed air turbine; and second group: where an electric handpiece was used. Surface roughness parameters were measured following resin clean up and after polishing using pumice and a rubber cup. Time needed for resin clean-up was recorded. Differences in enamel surface roughness and time between groups were compared using repeated measures ANOVA and independent samples t-test, respectively at P ≤ 0.05.ResultsThe electric handpiece groups showed significantly higher values for Ra, Rz and Rp both following resin cleanup and polishing. Time taken for resin cleanup was significantly longer for the electric handpiece group.ConclusionConsidering both surface roughness and time, electric handpiece do not seem to add greater effectiveness or efficiency to resin cleanup following orthodontic bracket debonding.

Quantitative and qualitative analysis of metallic ion release of orthodontic brackets in three different pH conditions - An invitro study

BackgroundFluoridated mouth rinses improve anti-cariogenic environment but decrease oral pH below critical value, affecting orthodontic bracket surface topography and causing corrosive changes over prolonged use. This invitro study aimed to quantitatively and qualitatively assess the surface topography and metallic ion release of the stainless steel (SS) brackets at varying acidic and alkaline pH. Materials and methodsForty unused SS brackets were divided into four groups (Group A, B, C, D) and immersed for 48- hours in solutions of artificial saliva and sodium fluoride (0.2 %) mouth rinse at varying pH of 5.5,6.7,7 and 8. The surface morphologic changes were analyzed under scanning electron microscope (SEM) at 50×, 150×, and 500× magnification. The changes in slot area were scored using the customized scale. The Energy Dispersive Xray Spectroscopy Analysis (EDAX) was used to estimate the probed elements' atomic and weight percentage. ResultsThe mean score of the scale was 3.4 for the brackets immersed in the acidic solution which was statistically significant (p = 0.00)and for alkaline and neutral solutions (p = 0.00). Chromium was found to be significantly higher in the alkaline solution (p = 0.016) followed by the neutral solution. Carbon was found excess in acidic solution than the neutral and alkaline solution. ConclusionQuantitative and qualitative analysis of the ion release in stainless steel brackets using SEM and EDAX revealed the corrosive effect of fluoride ion causing maximum surface changes in acidic medium and chromium release in alkaline pH.

In-Vitro Investigation of the Shear Bond Strength of Different Orthodontic Adhesives to Enamel.

The shear bond strength (SBS) of orthodontic adhesives to enamel is a critical factor in the success of orthodontic treatment. Various adhesives are available in the market, each with different trade names and claimed properties that could influence their bond strength. Understanding these differences is essential for clinical decision-making. In this in-vitro study, 60 freshly extracted human premolars were collected and randomly divided into four groups: Group A (Adhesive X-Trade Name: BondPlus), Group B (Adhesive Y-Trade Name: OrthoBond), Group C (Adhesive Z-Trade Name: PowerBond), and Group D (Control). The enamel surfaces were cleaned, polished, and etched following standard protocols. Orthodontic brackets were bonded to the teeth using the respective adhesives according to the manufacturer's instructions. A universal testing machine was employed to measure the SBS, and the data were analyzed using ANOVA with post-hoc tests. The mean SBS values (MPa) were as follows: Group A = 15.2, Group B = 14.8, Group C = 16.5, and Group D (Control) =10.3. Statistical analysis revealed significant differences among the groups (P < 0.05). Post-hoc tests indicated that Group C exhibited significantly higher SBS compared to the other groups. Our findings suggest that among the orthodontic adhesives tested, PowerBond demonstrated superior shear bond strength to the enamel. However, further research is warranted to explore other aspects of adhesive performance and clinical implications.

Antibacterial, cytotoxic and mechanical properties of a orthodontic cement with phosphate nano-sized and phosphorylated chitosan: An in vitro study

ObjectivesEvaluate, in vitro, the effect of incorporating nano-sized sodium trimetaphosphate (TMPnano) and phosphorylated chitosan (Chi-Ph) into resin-modified glass ionomer cement (RMGIC) used for orthodontic bracket cementation, on mechanical, fluoride release, antimicrobial and cytotoxic properties. MethodsRMGIC was combined with Chi-Ph (0.25%/0.5%) and/or TMPnano (14%). The diametral compressive/tensile strength (DCS/TS), surface hardness (SH) and degree of conversion (%DC) were determined. For fluoride (F) release, samples were immersed in des/remineralizing solutions. Antimicrobial/antibiofilm activity was evaluated by the agar diffusion test and biofilm metabolism (XTT). Cytotoxicity in fibroblasts was assessed with the resazurin method. ResultsAfter 24 h, the RMGIC-14%TMPnano group showed a lower TS value (p < 0.001); after 7 days the RMGIC-14%TMPnano-0.25%Chi-Ph group showed the highest value (p < 0.001). For DCS, the RMGIC group (24 h) showed the highest value (p < 0.001); after 7 days, the highest value was observed for the RMGIC-14%TMPnano-0.25%Chi-Ph (p < 0.001). RMGIC-14%TMPnano, RMGIC-14%TMPnano-0.25%Chi-Ph, RMGIC-14%TMPnano-0.5%Chi-Ph showed higher and similar release of F (p > 0.001). In the SH, the RMGIC-0.25%Chi-Ph; RMGIC-0.5%Chi-Ph; RMGIC-14%TMPnano-0.5%Chi-Ph groups showed similar results after 7 days (p > 0.001). The RMGIC-14%TMPnano-0.25%Chi-Ph group showed a better effect on microbial/antibiofilm growth, and the highest efficacy on cell viability (p < 0.001). After 72 h, only the RMGIC-14%TMPnano-0.25%Chi-Ph group showed cell viability (p < 0.001). ConclusionThe RMGIC-14%TMPnano-0.25%Chi-Ph did not alter the physical-mechanical properties, was not toxic to fibroblasts and reduced the viability and metabolism of S. mutans. Clinical relevanceThe addition of phosphorylated chitosan and organic phosphate to RMGIC could provide an antibiofilm and remineralizing effect on the tooth enamel of orthodontic patients, who are prone to a high cariogenic challenge due to fluctuations in oral pH and progression of carious lesions.