Methacrylate-based Composite Resins Research Articles

Bulk-Fill Ormocer versus Methacrylate-Based Resin Composite Restorative Systems: The Effect of Flowable Lining on Two-Year Clinical Performance in Class II Cavities

Bulk-Fill Ormocer versus Methacrylate-Based Resin Composite Restorative Systems: The Effect of Flowable Lining on Two-Year Clinical Performance in Class II Cavities

Effect of Composite Shade, Curing Time and Mode on Temperature Rise of Silorane and Methacrylate-Based Composite Resins

Effect of Composite Shade, Curing Time and Mode on Temperature Rise of Silorane and Methacrylate-Based Composite Resins

Effect of Shade and Light Curing Mode on the Degree of Conversion of Silorane-Based and Methacrylate-Based Resin Composites

Effect of Shade and Light Curing Mode on the Degree of Conversion of Silorane-Based and Methacrylate-Based Resin Composites

Effect of Different Surface Treatments on the Long-Term Repair Bond Strength of Aged Methacrylate-Based Resin Composite Restorations: A Systematic Review and Network Meta-analysis.

This systematic review and network meta-analysis is aimed at investigating the effect of common surface treatments on the long-term repair bond strength of aged resin composite restorations and to rank and compare these surface treatments. In vitro studies evaluating the methacrylate-based resin composites subjected to rigorous aging protocols before and after being repaired with a new composite were included. A frequentist network meta-analysis was carried out using a random effects model. P scores were used to rank the efficacy of the surface treatments. Also, the global and node-split inconsistencies were evaluated. Web of Science, PubMed/Medline, Scopus, and Embase databases were searched until July 07, 2022. Twenty-six studies were included in the meta-analysis. The results showed that the application of silane and a total-etch (shear MD 32.35 MPa, 95% CI: 18.25 to 46.40, P score 0.95; tensile MD 33.25 MPa, 95% CI: 25.07 to 41.44; P score 0.77) or a self-etch (shear MD 38.87 MPa, 95% CI: 21.60 to 56.14, P score 0.99; tensile MD 32.52 MPa, 95% CI: 23.74 to 41.29; P score 0.73) adhesion protocol subsequent to the roughening with diamond bur produced the highest (micro)tensile and (micro)shear bond strengths compared to diamond bur alone as the control group. There was no difference between self- and total-etch adhesive protocols. Mechanical surface treatments yielded greater bond strength when used alongside the chemical adhesive agents. Further, it is possible to achieve acceptable repair bond strength using common dental clinic equipment. Therefore, clinicians could consider repairing old resin composites rather than replacing them.

Release of leachable products from resinous compounds in the saliva of children with anterior open bite treated with spur.

To evaluate the release of bisphenol-A glycidyl methacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), bisphenol A (BPA), and phthalates of the composite resin used in the bonding of spurs applied in the treatment of children with anterior open bite and its effects on human keratinocytes. Saliva samples of 22 children were collected before spur attachment (baseline) and 30 minutes (min) and 24 hours (h) after spur bonding. Analysis was performed using high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (HPLC-MS/MS) and gas chromatography coupled to mass spectrometry (GC-MS). Standardized resin increments were added to three different dilutions of the cell culture medium. Keratinocytes (HaCaT) were cultivated in the conditioned media and evaluated for cell viability (MTT) and cell scratch assay. The levels of BisGMA (1.74±0.27 μg/mL), TEGDMA (2.29±0.36 μg/mL), and BPA (3.264±0.88 μg/L) in the saliva after 30 min, in comparison to baseline (0±0 μg/mL, 0±0 μg/mL, and 1.15±0.21 μg/L, respectively), presented higher numbers. After 24 h, the levels of the monomers were similar to the baseline. Phthalates showed no significant difference among groups. HaCat cells showed increased viability and reduced cell migration over time after exposure to methacrylate-based resin composites. Resin composites, used to attach spurs in children with anterior open bite during orthodontic treatment, release monomers after polymerization and can influence the behavior of human keratinocytes, even at very low concentrations. Orthodontists should be aware of the risks of the resinous compounds release and preventive procedures should be held to reduce patient exposure.

Can the type of preheated resin composite influence the microtensile bond strength of ceramic restoration to human dentin?

The aim of this study was to evaluate the effect of the type of preheated resin composite on the microtensile bond strength (µTBS) between dentin and feldspathic ceramic inlays. Thirty healthy human premolars received inlay preparations for feldspathic ceramic restorations and were then divided into three treatment groups according to the luting agent (n = 10): Conventional Resin Cement (RC), Preheated Nanofilled Methacrylate-Based Resin composite (MB), and Preheated Microhybrid Silorane-Based Resin composite (SB). The composite resin was preheated to 55 °C, considering the cementation group. After cementation, the sets were cut into slabs with a bonding area of 1 mm2 to be further submitted to the µTBS test (0.5 mm/min, and10 Kgf load cell). One-way ANOVA and Tukey test (p < .5) were performed to analyze the bond strength data (MPa). Failures were observed under a stereomicroscope and representative specimens were evaluated using a Scanning Electron Microscopy (SEM). ANOVA revealed that the type of luting agent utilized was significant (p = .001). Bond strength values for the RC (7.37 ± 1.27 MPa)A and MB (6.98 ± 1.96 MPa)A treatment groups were similar and greater than the SB (4.74 ± 1.65 MPa)B. Adhesive failures between the cementing agent and ceramic were prevalent for the treatment groups. The preheated nanofilled methacrylate resin-based composite technique can promote bond strength similar to resin cement, whereas preheated silorane-based resin composite as a luting agent should be seen with caution. Thus, we concluded that the type of luting agent has influenced the µTBS of feldspathic restoration to dentin.

Effect of degree of conversion of different resin composite monomers (methacrylate and silorane) on two caries-associated bacteria: “An in Vitro study”

Background and Objectives: The biological response of oral bacteria to dental restorative polymer composites is mediated by the release of unpolymerized residual monomers. The aims of the present study were first, evaluating the effect of composite elutes from methacrylate composite resins and silorane-based composites on two cariogenic bacterial pathogens: Streptococcus mutans and Lactobacillus acidophilus and second, determination of degree of conversion (DC) of standardized discs made from the low-shrinkage silorane-based composite (FiltekTM P90) resin and methacrylate-based composite resin (FiltekTM Z350XT nanocomposite, FiltekTM Z350 Flow) using Fourier transform infrared spectroscopy (FTIR). Materials and Methods: Thirty-six composite specimens were prepared for the agar diffusion test and dissolved in a solvent (dimethyl sulfoxide) to attain a suspension, which was used to assess the effect of the residual monomers from methacrylate composite resins and silorane-based composites on the growth of S. mutans and L. acidophilus. To avoid more dilutions of the specimens, the colonies of bacteria were counted by the naked eye. Thirty composite specimens of 2 mm × 6 mm were polymerized for DC test, and the DC was measured using FTIR, also for unpolymerized composite resin. Results: The growth of S. mutans bacteria was inhibited when cultured with Filtek Z350 Flow composite resin, while the growth of L. acidophilus bacteria was stimulated by the Filtek Silorane p90 and Filtek Z350 Flow composite resin. The DC test with the Filtek Silorane composite resin showed highest DC (58%), then the Filtek Z350XT (Nanocomposite) (42%) followed by the Filtek Z350 Flow (Flowable) showed lowest (35%). Conclusions: Our results demonstrate that composite filling materials have a versatile nature of effect on oral pathogenic bacteria, which could modulate their pathogenesis. Dentists may thus select the appropriate type of composite filling according to the caries susceptibility of patients.

Effect of fiber reinforcement on color stability and degree of polymerization of different composite resins

Aim: The aim of this in vitro study was to determine the effect of fiber-reinforcement on the color changes and degree of polymerization of two different composite resins. Materials and Methods: A bulk-fill composite resin and a methacrylate-based composite resin with A2 shade were used in this study. Three groups of specimens (control group with no reinforcements, polyethylene fiber-reinforced composite and glass fiber-reinforced composite groups) were prepared from each composite. The color change of the specimens with polymerization was measured. Then, to determine the degree of polymerization, the hardness ratios were calculated by measuring the bottom and top surface hardness of all specimens. The data were analyzed by analysis of variance, Duncan's multiple range tests, and Independent sample t-test. Results: Statistical analysis of variance presented the significance difference between composite and fiber for color change (P Conclusion: The addition of fiber may lead to color change and reduce the degree of polymerization of composite resins. The amount of change may differ depending on the structural properties of the composite resins and fiber.

Silane Coupling Agents are Beneficial for Resin Composite Repair: A Systematic Review and Meta-Analysis of In Vitro Studies.

To systematically review the literature to determine whether silane combined with adhesive application improves the repair bond strength of direct methacrylate-based resin composites in comparison to the use of an adhesive alone. The literature up to December 2019 was searched through PubMed/MEDLINE, Scopus, and Lilacs databases with no publication year or language limits. From 676 potentially eligible studies, 81 were selected for full-text analysis, and 19 were included in the systematic review. Two reviewers independently selected the studies, extracted data, and assessed the risk of bias. Meta-analyses were conducted using a random effects model to calculate pooled mean differences between adhesive- vs silane-plus-adhesive surface treatments (global meta-analysis) and considering subgroup analyses (immediate and aged repair bond strengths and type of silane - hydrolyzed or nonhydrolyzed). Statistical analyses were performed using RevMan5.3 at a significance level of 5%. Global meta-analysis showed that the use of silane prior to adhesive application produced significantly higher repair bond strengths (p=0.003). A higher mean difference (effect size: 7.30, 95% CI: 2.91-17.51) between groups was found when nonhydrolyzed silanes were used. The heterogeneity was high. Studies scored between medium and high risk of bias. An additional silane application step could increase the repair bond strength of methacrylate-based resin composites.

Effect of Light Intensity and Curing Time on Color Stability of a Methacrylate-Based Composite Resin Using an LED Light-Curing Unit

Background: Despite improvements in the optical properties of composite resins, their color stability is still a matter of discussion. This study sought to assess the effect of light intensity and curing time by a light-emitting diode (LED) light-curing unit on color stability of a methacrylate-based composite resin. Methods: In this in vitro study, 60 discs (8 × 2 mm) were fabricated of A2 shade of Z250 composite. Specimens were polished and divided into 4 groups (n=15) for curing for 20 or 40 seconds with a light intensity of 600 or 1200 mW/cm2 . After immersion in distilled water at 37°C for 24 hours, colorimetry was performed using a spectroradiometer. The specimens were then immersed in tea solution for 7 days (3 times a day, each time for one hour) and were subjected to colorimetry again. Color change (∆E) was calculated and analyzed using two-way ANOVA. Results: Significant color change was noted following an increase in curing time (P 0.05). The interaction effect of light intensity and curing time on color change was significant (P<0.05). Conclusions: Curing time is an important factor affecting the color stability of composite resin polymerized with LED light curing unit. On the other hand, increasing the light intensity over the standard threshold showed no significant effect.

Effect of Green Tea (Camellia sinensis) Solution on Color Change of Silorane- and Methacrylate-Based Composite Resins

Color change is an undesirable but avoidable effect in composite resin. Limited research has been conducted on the effect of green tea solution on silorane- and methacrylate-based composite resins. In this study, we used 30 silorane- and methacrylate-based composite resin disks (shade A3) (6 mm in diameter and 2 mm in thickness) prepared from Filtek P90 and Filtek Z250. Specimens were divided into six groups (n = 5), and each group was immersed in three green tea solutions at different concentrations (1%, 2%, and 3%) for 6 hours. Color assessment was performed with a spectrophotometer based on CIE*Lab theory, and results were subjected to statistical analysis using one-way ANOVA and independent t-test. Significant differences were observed in Δi* between the two composite disks after immersion in tea solutions (p < 0.05). Color change in silorane-based composite resin was higher than that in methacrylate-based resin; this color change was the highest when silorane-based composite resin was immersed in 3% green tea solution (ΔE = 3.85).

Silorane versus methacrylate composites: A comparative study of the micro-leakage

This in vitro study aimed to evaluate the micro-leakage at the occlusal and cervical margins in class II cavities in permanent molars restored with a low shrink silorane resin composite (Filtek P90) applied with or without etching and two methacrylate-based composite resins (valux plus and Amelogen® plus). Two standardised class II box cavities were prepared in proximal surfaces of 60 sound non-fluorotic permanent molars which were divided into three groups of 20 each according to the type of composite. Group I: silorane-based composite (Filtek P90) in the mesial cavity and methacrylate-based microhybrid composite (Adper single bond 2/valux plus) in the distal cavity, Group II: silorane-based composite in the mesial cavity and silorane-based composite with previous etching in the distal cavity, and Group III: silorane-based composite in the mesial cavity and methacrylate-based micro-hybrid composite (PQ1 /Amelogen plus) in the distal cavity. The samples underwent an artificial aging with thermocycling. Root apices were sealed with transparent orthodontic resin and coated with transparent varnish except 1 mm around the restoration. The specimens were immersed in 1% methylene blue solution at room temperature for 48 hour. The samples were sectioned longitudinally in the mesiodistal direction and evaluated under a stereomicroscope at 20X. Scoring was done according to the depth of methylene blue penetration into the cavities. Statistical analysis of the data was performed using SPSS 17.0 software. Silorane-based composite resin showed less micro-leakage than the methacrylate-based composites. Etching improved the sealing ability of silorane restorations. Silorane-based composite preceded by etching had less micro-leakage among the other materials used in this in vitro study. Keywords: Silorane, methacrylate based composite, sealing, micro-leakage, class II cavity

Comparison of the Shear Bond Strength of Silorane-Based Composite Resin and Methacrylate Based Composite Resin to MTA.

Background. Mineral trioxide aggregate (MTA) is a material that has recently gained popularity in the application of the vital pulp therapy. Along with the increasing use of MTA to this end, the permanent restoration material to be placed on MTA has become a significant issue. The aim of this in vitro study was to investigate the bond strength of the novel low-shrinkage silorane-based composite resin (SBC) to MTA. Methods. Twenty acrylic blocks filled with MTA were prepared for this study. SBC was the test group and methacrylate-based composite resin (MBC) was used as the control group. Shear bond strength test was performed to determine the bond strength. The surfaces of broken samples were evaluated under a stereomicroscope and grouped as adhesive, cohesive and mixed. Data were examined by statistical analysis. Results. Statistical analysis revealed that SBC exhibited higher shear bond strength than the control group. It was observed that most of the failures in the test group were of cohesive type within MTA. Conclusion. Based on the results, SBC showed higher shear bond strength than the control group; however, clinical follow-up is needed to evaluate the clinical success.

Effectiveness of the DHMAI monomer in the development of an antibacterial dental composite

ObjectiveDevelopment of antibacterial dental composites is the ultimate goal to decrease carious disease occurrence and increase the restoration longevity. For this purpose, the quaternary ammonium dimethyl-hexadecyl-methacryloxyethyl-ammonium iodide (DHMAI) and the methacryloyloxyethylphosphorylcholine (MPC) have been incorporated in experimental methacrylate-based composite resins. This aims to first investigate the effect of each alone and then their combined effect. MethodsSynthesized DHMAI and commercial MPC were added either alone or combined at different concentrations to experimental dental composite. Flexural strength (FS) and modulus (FM) were tested to select the optimal concentrations. Only selected composites were evaluated for Vickers hardness (HV) and the degree of conversion (DC) using fourier transform infrared spectroscopy analysis (FTIR-ATR). Antibacterial activity was assessed using tests on colony-forming unit (CFU), scanning electron microscopy (SEM) and Alamarblue assay to measure the metabolic activity. Streptococcus mutans biofilm was chosen to be grown on the composite surfaces during 96h at 37°C. ResultsIncorporation of 7.5% DHMAI in composite improved the degree of conversion and gave a strong antibacterial effect with a reduction of (∼98%) in CFU and (∼50%) of metabolic activity with acceptable mechanical properties. Addition of MPC to DHMAI affects mechanical properties of composites without providing a better antibacterial activity. SignificanceComposites with DHMAI greatly reduced S. mutans biofilm and improved the degree of conversion without scarifying the composites’ mechanical properties. DHMAI may have wide applicability to other dental materials in order to inhibit caries and improve the longevity of restorations.

Acoustic emission characteristics of methacrylate-based composite and silorane-based composite during dental restoration according to a variety of C-factor

Acoustic emission (AE) characteristics according to a variety of Configuration factor (C-factor) of methacrylate-based composite resin (Clearfil AP-X, Kuraray) and silorane-based composite resin (Filtek P90, 3M ESPE) during dental restoration were investigated in combination with the Finite element stress analysis (FESA). AE measurement results showed that most micro-cracks occurred within 1 min after the light irradiation started. As the C-factor increased, average cumulative AE hits and average cumulative AE energy increased. Those AE parameters for AP-X with high shrinkage strain were higher than P90 with low shrinkage strain. FESA results showed that the maximum shrinkage stress appeared at the resin/tooth interface on the specimen surface. The stress of AP-X was bigger than that of P90, which coincided with the AE behaviors with increasing C-factor.

Effect of water storage on flexural strength of silorane and methacrylate-based composite resins.

ObjectivesThis study assessed the effect of water storage on the flexural strength (FS) of low shrinkage composites.Materials and MethodsA total of 165 bar-shaped specimens (2 × 2 × 25 mm) were fabricated of 2 low shrinkage composites (Filtek P90 [3M ESPE], GC Kalore [GC International]) and a conventional methacrylate-based composite (Filtek Z250 [3M ESPE]). The specimens were subjected to 3-point bending test at 6 time intervals, namely: immediately after curing, at 24 hours, 1 week, 1 month, 6 months, and 1 year following storage in wet and dry conditions. The FS of the specimens were measured by applying compressive load at a crosshead speed of 1.0 mm/min. Data was analyzed using 3-way analysis of variance (ANOVA) and Tukey's test.ResultsThree-way ANOVA revealed significant interactions between time, type of composite, and storage condition (p = 0.001). Tukey's multiple comparison test revealed significant reductions in FS of all composites after 6 months and 1 year of storage in distilled water compared to dry condition.ConclusionsFiltek P90 showed the highest and GC Kalore showed the lowest FS after 1 year storage in distilled water. The immediate high strength of Filtek Z250 significantly decreased at 1 year and its final value was lower than that of Filtek P90.

The Silorane-based Resin Composites: A Review.

This article aims to review the research done on the silorane-based resin composites (SBRC) regarding polymerization shrinkage and contraction stresses and their ability to improve the shortcomings of the methacrylate-based resin composites (MRBC). Special attention is given to their physical and mechanical properties, bond strength, marginal adaptation, and cusp deflection. The clinical significance of this material is critically appraised with a focus on the ability of SBRC to strengthen the tooth structure as a direct restorative material. A search of English peer-reviewed dental literature (2003-2015) from PubMed and MEDLINE databases was conducted with the terms "low shrinkage" and "silorane composites." The list was screened, and 70 articles that were relevant to the objectives of this work were included.

Effect of Oxalic Acid–Based Desensitizing Agent on Cervical Restorations on Hypersensitive Teeth: A Triple-Blind Randomized Controlled Clinical Trial

To assess the effects of application of an oxalic acid-based desensitizing agent before restoration of noncarious cervical lesions (NCCLs) with either a silorane-based or a methacrylate-based composite resin on decreasing the absolute risk and intensity of dentin hypersensitivity over the course of a 1-year follow-up. NCCLs in 31 patients (age range 24-66 years) were selected and randomly divided into four groups (n = 31 in all groups). In the Z250 and P90 groups, the restorations were performed with a methacrylate-based composite resin (Filtek Z250) and a silorane-based composite resin (Silorane P90), respectively. In the Z250 + OA and P90 + OA groups, the same composite resins were used, but an oxalic acid-based desensitizing agent (Desenssiv, SSWhite) was first applied. All NCCLs were evaluated before restoration (BR) and at 30, 60, 90, 180, and 360 days after treatment. Teeth sensitivity to evaporative and tactile stimuli was measured by a visual analog scale (VAS). The results were analyzed with statistical tools including Wilcoxon and Friedman tests for within-group comparisons and ANOVA and Bonferroni post hoc tests for between-group comparisons (P < .05). Reduction in dentin hypersensitivity was observed for all treatment groups; however, these reductions were more pronounced when oxalic acid was applied before restoring the NCCL (P < .001). Complete elimination of pain was not achieved by any treatment modalities for the first 6 months; afterwards, in the groups that had received application of the oxalate-based desensitizing agent, the absolute risk of dentin hypersensitivity was significantly reduced (P < .01). The restoration of sensitive NCCLs with composite resins reduces dentin hypersensitivity. This reduction is more pronounced if an oxalic acid-based desensitizing agent is applied prior to the restoration. In addition, its application reduces the absolute risk of dentin hypersensitivity after 6 months of treatment.

Effect of Mouth Rinses on Surface Roughness of Two Methacrylate-Based and Siloraine-Based Composite Resins

Background: Various fluids in the oral environment can affect the surface roughness of resin composites. This in vitro study was conducted to determine the influence of the mouth rinses on surface roughness of two methacrylate-based resin (nanofilled and packable composite) and siloraine-based resin composites. Materials and methods : Disc-sh aped specimens (12 mm in diameter and 2mm in height) were prepared from three types of composite resin materials: Filtek™ Z350 XT, Filtek™ P60 and Filtek™ P90.Thirty specimens were prepared from each composite type and subdivided into three subgroups (n=10 ) according to the type of treatment solution: distilled water (control), Listerine (alcohol-containing), Sensodyne Pronamel (alcohol free fluoride- containing). Each subgroup was immersed in 20 ml of treatment solutions and incubated at 37°C for 24 hr and then subjected to surface roughness test by profilometer .The resulting data were statistically analyzed using ANOVA and LSD test at0.05 significance level. Results : The results of this study showed that both mouth rinses irrespective of the presence or absence of alcohol resulted in significant increase in the surface roughness of the tested resin composite materials compared to control with no significant difference between the two mouth rinses. Comparison among the three types of resin in each treatment solution showed that there was a statistically high significant difference in surface roughness between all subgroups Conclusion : Both alcohol-containing and alcohol-free fluoride containing mouth rinses cause highly significant increase in surface roughness of composite resins. Composite changes depended on the material itself rather than the mouth rinse solution used. Key word s : Composite resin, mouth rinses, siloraine, surfaces roughness.

Effect of Dental Bleaching on the Fracture Toughness of Silorane and Methacrylate-Based Composite Resins

Effect of Dental Bleaching on the Fracture Toughness of Silorane and Methacrylate-Based Composite Resins