Biomineralizing Dental Resin Empowered by Bioactive Amphiphilic

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Biomineralizing Dental Resin Empowered by Bioactive Amphiphilic Composite Nanoparticles Ailing Li, Yang Cui, Shan Gao, Qiuju Li, Liju Xu, Xiaohui Meng, Yanmei Dong, Xiaoling Liu, and Dong Qiu ACS Appl. Bio Mater., Just Accepted Manuscript • DOI: 10.1021/acsabm.9b00051 • Publication Date (Web): 29 Mar 2019 Downloaded from http://pubs.acs.org on March 29, 2019

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ACS Applied Bio Materials

Biomineralizing Dental Resin Empowered by Bioactive Amphiphilic Composite Nanoparticles Ailing Lia, Yang Cuiab, Shan Gaoc, Qiuju Lid, Liju Xu ab, Xiaohui Meng a,Yanmei Dongd, Xiaoling Liue, Dong Qiu*ab a

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China b University of Chinese Academy of Sciences, Beijing 100190, China c Orthopedic Department, Peking University Third Hospital, Beijing 100191, China d Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China. e University of Nottingham Ningbo China, Ningbo 315100, China

Abstract: Adhesive failure on account of resin contraction is one of the major reasons for dental restoration failure, which will lead to the exposure of dentinal tubules, and remineralization in saliva would provide a great solution for the above problem. In this study, bioactive amphiphilic raspberry-like composite nanoparticles were used as fillers for resin composites, which have good compatibility with the resin matrix and dispersed well in the matrix. Thus, the resin composites showed improved mechanical property and resistance to water sorption and solubility. Furthermore, the incorporation of bioactive nanoparticles endued the resin composites with bioactivity, forming apatite on resin composites upon reacting with artificial saliva (AS) within 7 days, inducing denser mineral precipitation on dentin surface and stimulating human dental pulp cells (hDPCs) attachment and proliferation. Therefore, these bioactive nanoparticle filled composite resin may offer great benefits for dental restoration.

Keywords: Dental restoration resin composites, Remineralization, Dentine, Bioactive composite nanoparticles

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1. INTRODUCTION Dental resin composites have been increasingly used as restorative materials for dental caries because of their excellent esthetics and improved performances.1-4 However, contraction of dental resin during the curing process often results in adhesive failure and leads to the exposure of the dentinal tubules, which is susceptible for microbe penetration and may eventually lead to secondary caries and failure of restoration.5-12 Sealing the exposed dentinal tubules through mineralization in saliva provides a great solution for the above problems. Therefore, it would be highly desirable for the dental resin composite to possess mineralization capability. Silicate based bioactive glasses (BG) have proven to induce hydroxyapatite (HA) precipitation in saliva under physiological conditions, for such reason, BG has been explored as a bioactive filler into dental resin in order to obtain biomineralizing restoration resins.13,14 However, BG fillers are hydrophilic and incompatible with the hydrophobic resin matrix; they tend to aggregate in resin matrix, which often leads to severe deterioration of resin mechanical properties.15 In tackling this problem, BG fillers were hydrophobically modified to bear better compatibility or even to form chemical bond with resin matrix.16-18 However, to induce HA formation, BG surface needs to directly contact with saliva, which limits the extent of hydrophobic modification, therefore, the improvement of their compatibility with resin matrix is marginal. Alterative strategy is needed to circumvent this dilemma. Raspberry-like composite structure with bioactive glass particles partially embedded in hydrophobic matrix resin may get around this dilemma (Scheme 1). Such structure allows the composite fillers to be well compatible with resin matrix through the hydrophobic regions and the direct contact of BG particles with saliva. As an example, the bioactive amphiphilic raspberry-like composite nanoparticles (BRPs) filled bone cement showed good mechanical properties and mineralization capacity.19 These BRPs may serve as excellent fillers for dental resin as well, thus to obtain biomineralizing restoration resin. With such design, the contradictory between glass-resin interfacial compatibility can be harmonized, and the exposed dentinal tubules can be sealed by the apatite formation (Scheme 1).


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Scheme 1. Schematic demonstration of the specific mix of BRP and Resin matrix and the subsequent in situ remineralization of HA 2. MATERIALS AND METHODS 2.1 Materials Triethylene glycol dimethacrylate (TEGDMA), Bisphenol A glycerolate dimethacrylate (bisGMA), 2-(dimethylamino) ethyl methacrylate (DMAEMA) and camphoroquinone (CQ) were obtained from Aldrich. Ludox silica TM40 (25 nm) was purchased from Sigma-Aldrich. Potassium persulfate (KPS) and 3-(Trimethoxysilyl) propyl methacrylate (TPM) were purchased from Alfa. Bioactive glasses (Bioglas®: Na2O-24.4 mol%, P2O5-2.6 mol%, CaO-26.9 mol%, SiO2-46.1 mol%) were purchased from Schott. BRPs were synthesized as previously reported: 19 a Ludox silica dispersion was stirred with TPM for 24 h, then initiated with KPS for the polymerization to obtain raspberry-like composite nanoparticles (RPs). And then the surfaces of the particles were modified with Ca2+ to synthesis bioactive amphiphilic raspberry-like composite nanoparticles (BRPs). The resultant products were purified by centrifugation and washing with water, then freeze-dried for further application. The morphology of the particles were examined by Transmission electron microscopy (TEM). The



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chemical conformation of BRP was shown in Figure S1 (Supporting information). In which, the surface hydrophilic bioactive domain (small particles extruded from the surface) promote hydroxyapatite (HA) formation when immersed in body fluids, and the hydrophobic polymer domain (center part) promote well compatibility with polymer matrix. . 2.2 Preparation of resin composites As shown in scheme 1, the monomers (TEGDMA-49.5wt%, Bis-GMA- 49.5wt%) and initiators (CQ-0.2wt%, DMAEMA-0.8wt%) were uniformly mixed using a stirrer at 60℃ for 1 h in a lightproof container (BT), and then the BRPs (33 wt%) were slowly added into the BT mixing in a rotation and revolution mixer (ARE-310, Thinky Mixer, Japan) for 2 min at 2000 rpm followed by 1 min at 2200 rpm to get BT/BRP samples. Bioglas® particles (BG, 33 wt%) which previously have been incorporated within the resin composites and proved to have high water sorption and solubility were added into the above BT for comparison (BT/BG).13 The unfilled resin (BT) also served as a control. Afterwards, the composites were poured into the rectangular (2 mm×2 mm×25 mm; or 6 mm×2 mm×3 mm) or circle (15 mm diameter; or 10 mm diameter; 1 mm thickness) TEFLON cylinder molds, and covered by glass slides. Then the sample was light-cured (600-800 mW/cm2) for 60 s on both sides (Bluephase N®, Ivoclar Vivadent). The sand paper with a grit number of 1000# was used to polish the samples. 2.3 Water solubility and water sorption Water solubility and water sorption of the resultant resin composite samples were determined following the ISO 4049-2009. Three discs (1 mm thickness, 15 mm diameter) of every sample (BT, BT/BG or BT/BRP) was placed in a 37℃ desiccator that contain allochroic silicagel to get a constant weight (m0). The samples were subsequently immersed in 20 mL pure water at 37℃. After 7 days immersion, the samples were dried and weighed (m1). The volume of the sample was defined as V (mm-3). The samples were then dried in a 37℃ desiccator that contain allochroic silicagel to get the final constant weight (m2). The max water solubility [(m0-m2)/V] and the water sorption [(m1-m2)/V] were calculated. Means and standard deviations for water solubility and water sorption (mg·mm-3) were calculated for each group. 2.4 In vitro apatite formation In vitro HA formation was determined by immersing 150 mg of resin composite discs in 100 mL


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of artificial saliva (AS) at 37℃. AS (pH 7.4) contain 50 mmol/L KCl, 1.5mmol/L CaCl2, 0.9 mmol/L KH2PO4 and 20 mmol/L Tris(Hydroxymethyl)aminomethane (Tris).14 After immersed in AS for 7 days and 14 days, the samples were washed with pure water for three times and left to dry in a desiccator. The apatite formation on the samples was evaluated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). 2.5 Degradation of dental resin Three discs (75 mg) were immersed in 50 mL of AS at 37℃ and stirred at 120 rpm, respectively. At every time points (1, 7, 14, 21 and 28 d), the discs were removed and dried under vacuum prior to weighing. To obtain the weight change rate, the initial weight (M0) and the weight remaining at time t (Mt) of each sample were measured to give a weight change %: weight (%) = Mt/M0×100%. The pH values of every extracts (BT, BT/BG and BT/BRP) were recorded after 0.5, 1, 3, 5 and 30 days immersion. 2.6 Mechanical testing Flexural strength (or modulus) of the resin composites were measured by the three-point bending test (crosshead speed 0.5 mm/min, span 20 mm) on Instron3365 (Instron Co., Canton, MA, USA) at 50±5 % relative humidity and 23±2℃conditions. Five rectangular bar (2 mm×2 mm×25 mm) of every sample were measured. The mean and standard deviation were reported. 2.7 Cell evaluation Preparation of resin composites extracts. Different resin composites (BT, BT/BG, BT/BRP) were sterilized under UV light for 12 h, then they were immersed in α-MEM that preheated to 37℃, and the extracting vehicle ratio was 1.25 cm2/mL in accordance with ISO 10993-12:2007. After 24 h under sterile conditions at 37℃, α-MEM was filtered, and the extracts were added with 10% fetal bovine serum (FBS) using as culture medium. Cell viability assays. As previously described methods, impacted third molars of patients aged 1925 years were chosen to isolate Human dental pulp cells (hDPCs).20 The hDPCs were cultured in a condition containing 5 % CO2 at 37℃. α-MEM added with 10% FBS was used as the culture medium. Cell viability was evaluated by a Cell Count Kit-8 (CCK-8, Beyotime, Jiangsu, China). The hDPCs were seeded on a 96-well culture plate at a density of 2×105 cells per well and cultured overnight. The culture medium of each well was replaced by different resin composite extracts. The hDPCs incubated in α-MEM without resin composite extract were chosen as control. They were incubated for 1, 3 and



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7 days. Then, 20 μL CCK-8 solution (per well) was added and incubated for 2 h at the condition of 5 % CO2 and 37℃, and the reacted reagent (100 μL) from each well was transferred to a 96-well plate, and a micro-plate spectrophotometer (MD, SpectraMax M2, USA) was used to determine the absorbance at 450 nm. Statistics were performed from six parallel replicates of each sample at each time point. Cell Morphology. The resin composite pellets (10 mm diameter, 1 mm thickness) were used for cell seeding. First, all the composites were disinfected with 70 % ethyl alcohol solution for 2 h, washing twice with PBS for 0.5 h, and then sterilizing under UV light for 4 h. Afterwards, the composite pellets were put into 48-well culture plate. hDPCs at a density of 2×105 cells per well was cultured in composites for 3 days. The adherent cells were fixed in 4 % paraformaldehyde for 0.5 h, then rinsing with PBS for 2 times. For morphological observations, the actin skeleton of the seeded cells was labeled by culturing with 200 μL of phalloidin-TRITC (1:400, Sigma) for 2 h. After rinsing with PBS, the cell nucleus were labeled in blue by Hoechst-33258（1:800, Sigma）for 0.5 h. Then the cell morphology test was evaluated by a confocal laser scanning microscopy (CLSM, TCS SP5, Leica, German). 2.8 Dentin Specimens Preparation In accordance with the ethical guidelines of the research ethics committee, ten caries-free human molars were used and stored in water at 4℃, using within 1 month after extraction. To reduce the tooth-effect variability, beams with the size of 5 mm×1 mm×1 mm were obtained from the mid-coronal dentin (total = 30) and distributed into 3 groups (n=10/group): 1) BT, 2) BT/BG, and 3) BT/BRP. Every dentin beam was demineralized in 10 % phosphoric acid solution for 12 h at 25℃, then contacting directly (only on one side) with cured resin (BT, BT/BG and BT/BRP) beams (6mm×3mm×2mm) using orthodontics rubber bands.21 The samples’ surfaces were observed by SEM. 2.9 Characterization TEM of resin composites was performed on a JEM 2200FS (JEOL, Japan, 200 kV). XRD spectra was collected on a Rigaku instrument (D/MAX 2500) with Cu Ka radiation (λ=0.154 nm) in the 2θ range 5-70ºwith a step size of 0.02º(200 mA, 40 kV). SEM of samples firstly were sputtered (SCD 500) with a thin layer of gold (Au), and then the surfaces were observed using JEOL-6700 instrument (5 kV). 2.10 Statistical analysis The significant differences between means in the measured data were evaluated using the one-


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way analysis of variance (ANOVA). All the experiment were repeated three times, and all the quantitative data are presented as mean ±standard deviation. 3 RESULTS AND DISCUSSION 3.1 Bioactive fillers for resin composites The morphology of BRPs are shown in Figure 1a. The diameters of BRPs are ~100nm. They have hydrophilic bioactive domain for hydroxyapatite (HA) formation when immersed in body fluids, and also have hydrophobic polymer domain to promote well compatibility with polymer matrix.

19

Therefore, they are expected to be used as fillers for remineralization property of resin composites. Micro-sized bioactive glasses (BG, 45S5) have remarkable HA formation capability when immersed in body fluids, and they have been widely used in dentine remineralization, such as tooth pastes and desensitizing pastes.22-24 And they have also been widely used as fillers for the study of resin-based dental materials, and it has been successfully proven that the materials based on BG could promote dentine remineralization.13 Thus, the BG particles will be used as comparison fillers in this paper, and the particles morphology is shown in Figure 1b. Resin composites of BT, BT/BG and BT/BRP were produced as shown in Figure 1c.

Figure 1. (a) TEM image of BRPs; (b) SEM image of BG; (c) optical photos of BT, BT/BG and BT/BRP; XRD spectra of different samples after immersed in AS for different times: (d) BT; (e)



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BT/BG; (f) BT/BRP (● hydroxyapatite, ○ calcium carbonate) In order to evaluate the in vitro apatite formation property of the composites BT, BT/BG and BT/BRP, they were immersed in AS solution for different times. Before immersion in AS, all the samples are totally amorphous (Figure 1d, e and f). After immersion in AS, no hydroxyapatite (HA) form for the BT samples, however, HA diffraction peaks appear for BT/BG and BT/BRP samples after 7 d immersion and then increase in magnitude with the increase of immersion time, confirming HA formation for these materials. And BT/BRP have similar apatite formation with BT/BG, which means that BRPs containing composites have similar bioactivity with BG containing composites. The apatite formation was further confirmed by SEM images (Figure 2). It can be seen that before immersed in AS, some micro-BG particles appeared on the surface of BT/BG composites (Figure 2b), and the BRPs particles dispersed well on the surface of BT/BRP composites (Figure 2c). After immersed in AS for 7 days, hemispherical or needle like apatite form on the surface of BT/BG and BT/BRP samples (Figure 2 e, f), however, no apatite form on the surface of BT sample, which are similar with the XRD results. In addition to that, many pores appear on the surface of the BT/BG samples after immersed in AS (Figure 2e). This may because the micro-BG fillers are hydrophilic and have insufficient compatibility with resin matrix, part of the particles in BT/BG composites may be released as particles.

Figure 2. The SEM image of different samples before and after immersed in AS: before immersion (0d): a-BT; b-BT/BG; c-BT/BRP; after immersion (7days): d-BT; e-BT/BG; f-BT/BRP. (The insets


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are higher magnifications, the arrows point to the BG particles) 3.2 Mechanical property Resin composites are clinically subjected to masticatory stresses, thus it is critical to have high flexural strength. As shown in Figure 3, the flexural strength of both BG and BRPs containing composites (BT/BG and BT/BRP) are significant lower than the BT composites, however, BT/BRP composites have significant higher flexural strength than BT/BG composites. And BT/BRP composites have the strongest flexural modulus comparing with BT and BT/BG composites. This means that BRPs containing composites have higher mechanical property than BG containing composites. In previously, BRPs have been found to have good compatibility with both water and methyl methacrylate (MMA), and dispersed well in PMMA cements.19 Because the resin composites have similar methacrylate based monomers for polymerization, the amphiphilic BRPs would have better compatibility with resin matrix; And also because BRPs particle size are much smaller than BG, thus further ensuring their improving mechanical property.

Figure 3. The flexural strength and modulus of BT, BT/BG and BT/BRP composites (statistical significance: **p < 0.01 vs. BT; #p< 0.01vs. BT/BG) 3.3 Water diffusion and degradation studies In accordance with ISO 4049-2009, dental restorative resins should have water solubility and sorption lower than 7.5μg·mm-3 and 40 μg·mm-3, respectively. The water solubility and sorption results of this study are presented in Figure 4a. It is shown that the water solubility and sorption of BT are 8.3 μg·mm-3 and 40.8 μg·mm-3, which are a little higher than the requirement of ISO standard and could be improved by adding different fillers.25 And the water solubility and sorption of BG containing composites are 127.8 μg·mm-3 and 119.4 μg·mm-3, which are significant higher than BT composites,



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thus they could not be used as fillers for restorative resin materials. This may because that BG particles have great hydrophilicity and could induce the incorporation of a great deal of water. And higher water solubility and sorption may reflect the minor gaps existence in the structure of resin composites. However, the water solubility and sorption of BRPs containing composites are 7.5 μg·mm-3 and 44.2 μg·mm-3, which are very similar with BT composites. This means that the BRPs as fillers didn’t have any effect on the water solubility and sorption of resin composites. Therefore, BRPs as fillers will not only have good apatite formation, but also improve the mechanical property and water solubility and sorption of resin composites. In future work，BRPs combining with other particles as fillers for resin composites would be further studied to meet the requirement of ISO 4049.

Figure 4 (a)Water sorption and water solubility of BT, BT/BRP and BT/BG composites (statistical significance: **p < 0.01 vs. BT); (b) Weight change of BT, BT/BRP and BT/BG composites as a function of soaking time in AS solution; (c) pH values of the materials as a function of soaking time in AS solution Artificial fluids may diffuse into the filler-matrix interface and induce a chemical reaction once absorbed by the fillers, and fillers release ions to the liquid evoking the bioactive processes for mineral precipitation and leading to a degradation behavior. An evaluation of the degradation behavior of the BT, BT/BG and BT/BRP composites were conducted through weight change upon reaction with AS solution, as shown in Figure 4b. The weight decrease a little for BT and BT/BRP composites (~3%, 4 weeks), however, the weight decreased rapidly for BT/BG composite at~11% at 4 weeks. This may because that BG micro particles have poor compatibility with resin matrix, and some of them leach out from the materials surface during the immersion in AS (Figure 2e), leading to the higher degradation rate for resin composites. In addition to that, hydrophilicity BG will release much higher ions in AS for mineral precipitation, further leading to the higher degradation rate. The little degradation rate of BT may be due to the unreacted monomers release. And the little degradation rate


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of BT/BRP may be due to the little surface ion release of resin composites for mineral precipitation. The pH value of the resin composites tested in this study are shown in Figure 4c. BT/BG composites induced an increase in the pH value of the storage solution (~7.5) at 1d, and which is higher than BT and BT/BRP composites. This may because the higher degradation rate of the BT/BG composites have higher ions release rate, such as Ca2+ and Na+, taking ion exchange with the H+ protons in media, then leading to the higher pH value. 3.4 Cell evaluation The resin composites in clinical may contact with human dental pulp, thus hDPCs were chosen to evaluate the cell proliferation and morphology. The proliferation of hDPCs cultured with BT, BT/BG and BT/BRP extracts for 1, 3 and 7 days is shown in Figure 5. At 1 day, hDPCs cultured with BT extracts show slightly reduction in cell proliferation, and hDPCs cultured with BT/BG and BT/BRP extracts showed significant reduction in cell proliferation comparing with the negative control respectively. At day 3, hDPCs proliferation cultured with BT extracts is similar with the control, however, both BT/BG and BT/BRP extracts had a significant descending cell proliferation, and BT/BG descend much more than BT/BRP extracts. At 7 days, hDPCs proliferation cultured with BT extracts reduce slightly, however, hDPCs have a well proliferation for BT/BG and BT/BRP extracts, and BT/BG have a significant reduction in cell proliferation comparing with the control, while the BT/BRP have a similar cell proliferation comparing with the control, which means that BT/BRP have a better cell proliferation than BT/BG samples. As a comparison with hDPCs, the fibroblasts (L929) were also used to estimate the cell viability of BT, BT/BG and BT/BRP, it was found that all the composites are biocompatible with both hDPCs and L929 cells (Figure S2, Supporting information).



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Figure 5 Cell viability of hDPCs treated with BT, BT/BG and BT/BRP extracts for 1d, 3d and 7d (statistical significance: *p < 0.05 vs. Control) The cell compatibility was also proven to be associated with the cell adhesion behaviors, relating to well-spread of cell adhesion and attachment of its filopodia to the materials surface.26, 27 Cell nuclei and actin cytoskeletons were labeled to observe the cell morphology of hDPCs cultured with BT, BT/BG and BT/BRP pellets respectively (Figure 6). It is shown that hDPCs cultured with BT/BG samples show few cell attachment, and BT/BRP and BT samples demonstrate a well cell attachment. And, BT/BRP samples show much better cell attachment with more cytoplasmic extensions and actin microfilament. The distinguished cell morphology and skeleton alignment on materials indicated a good biocompatibility with the material and an active extracellular matrix formation.28 Therefore, BT/BRP have much better biocompatibility than BT/BG samples, which may be due to the higher pH value of BT/BG composites in medium influencing the cell compatibility (Figure 4c).29


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Figure 6 Cell morphology observation of hDPCs treated with BT, BT/BRP and BT/BG samples for 3 days (actin filament-red, cell nuclei-blue) 3.5 Dentin remineralization Dentin remineralization was tested to see whether the resin composites could promote mineral precipitation, as shown in Figure 7. It is shown that no mineral precipitate onto the surface of the dentin for BT composites, however, the BT/BG and BT/BRP resin composites can promote the precipitation of mineral layer onto the surface of dentin, and the dentin tubules coverage rate of BT/BRP (~63%) is much higher than BT/BG (~32%). For BT/BG composites, the remineralization process may due to Si4+ release and a subsequent polycondensation forming a silica-rich layer (Si-gel), then combining with the released Ca2+ and PO43- ions to precipitate into an amorphous CaO-P2O5, and the further



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incorporation of Ca2+ and PO43- ions from AS helps much more mineral formation.14 And, some of micro particles similar with BG particle (Figure 1b) were found on the demineralized dentin surface (Figure 7), which may because of the poor compatibility of BG with resin matrix leading to the BG release as particles, further confirming the surface pore of resin composites after immersion in artificial fluids (Figure 2e). For BT/BRP composites, the remineralization process may because BRPs release Ca2+ ions into the artificial fluids, then combining with the various mineral ions (Ca2+ and PO43-) in AS to form mineral layer. The mineral layer for BT/BRP seemed to be much denser than BT/BG on the surface of demineralized dentin surface, which may be due to their well compatibility with resin matrix, and the mineral formation only derived from ions of BRPs and artificial fluids but not from particles leached out from composites.

Figure 7 The SEM image of dentine remineralization induced by the three composites (BT, BT/BG and BT/BRP) after immersed in AS for 30 days (the arrows point to the BG particles) In this study, BRPs containing resin composites could not only improve the water sorption and solubility, mechanical property and cell biocompatibility, but also could form mineral layer on the dentin surface, therefore BRP particles as fillers may have great potential for restorative materials. Future studies should focus on the depth of the remineralization. Further in vitro analyses should evaluate whether the BRPs used in this study may improve the biomechanical properties of elasticity and hardness of the resin composites, and finally improve the marginal adaptation between dentin and resin composites. 4 CONCLUSIONS In summary, it was concluded that BRPs containing resin composites have similar apatite formation with the BG containing resin composites as revealed by SEM and XRD results. However, BRPs containing resin composites have improved mechanical property and resistance to water sorption and solubility, due to their amphiphilic surface properties. BRPs containing resin composites also have


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better cell biocompatibility and remineralization ability on the surface of demineralized dentin. Therefore, BRPs may be potential fillers for dental resin composites.

ASSOCIATED CONTENT Supporting Information 1, Chemical conformation of BRP; 2, Cell viability of hDPCs and L929 treated with BT, BT/BG and BT/BRP extracts for 1d

AUTHOR INFORMATION Corresponding Author *E-mail: [email protected] (D.Q.). ORCID Dong Qiu: 0000-0001-6320-0913 Notes The authors declare no competing financial interest. ACKNOWLEDGMENTS This work was financially supported by NSFC (Project No. 51603210, 21704106 and 51773209), the National Basic Research Program (2017YFC1103300), and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB12020300). REFERENCES [1] Vouvoudi E. C.; Sideridou I. D. Effect of Food/Oral-Simulating Liquids on Dynamic Mechanical Thermal Properties of Dental Nanohybrid Light-Cured Resin Composites. Dent. Mater. 2013, 29, 842850. [2] Sideridou I. D.; Vouvoudi E. C.; Bourdouni K. A. Study of Physicochemical Properties of two Current Commercial Dental Self-Curing Resin Composites. J. Appl. Polym. Sci. 2012, 126, 367-374. [3] Vouvoudi E. C.; Sideridou I. D. Dynamic Mechanical Properties of Dental Nanofilled Light-cured Resin Composites: Effect of Food-Simulating Liquids. J. Mech. Behav. Biomed. 2012, 10, 87-96. [4] Vouvoudi E. C.; Achilias D. S.; Sideridou I. D. Dental Light-cured Nanocomposites Based on a Dimethacrylate Matrix: Thermal Degradation and Isoconversional Kinetic Analysis in N-2 Atmosphere. Thermochim. Acta 2015, 599, 63-72.



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Biomineralizing Dental Resin Empowered by Bioactive Amphiphilic

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