Filtek Bulk Fill Research Articles

The effect of a bleaching agent on the pigment removal and the bond strength of bulk-fill resin composites: an in vitro study

Abstract Introduction In order to simplify the technique, reduce the time required for direct adhesive restorations, bulk-fill resin composites have been developed be applied in bulk placement up to 4 mm increments. Objective Evaluating the color change (ΔE) and the microtensile bond strength (μTBS) of bulk fill resin composites (BFRC) to dentin after the immersion in regular beverages and the application of bleaching systems. Method Forty-five human molar teeth were randomly distributed in three groups according to the filling material (n=15): Filtek Bulk Fill, Tetric N Ceram Bulk Fill and Filtek Z100. The restored teeth were immersed in coffee, wine and distilled water (n=5) for 72 hours. The color parameters were measured using a spectrophotometer, having as basis the CIE L*a*b*, before and after tooth staining and application of bleaching processes. Subsequently, the teeth were sectioned to obtain the specimens for the microtensile testing. The ΔE values were analyzed applying the Kruskal-Wallis and the Wilcoxon tests, and the μTBS values were analyzed applying the ANOVA and the Bonferroni tests (p<0.05). Result There were no significant differences in the ∆E values when comparing the BFRCs to the conventional resin composite (CRC) in most of the experimental groups. The ∆E values did not present significant differences before and after the application of bleaching processes for all the tested resin composites. The BFRCs presented higher μTBS values than the CRC after exposure to distilled water, wine and bleaching agent. Conclusion The studied BFRCs presented similar color stability to the CRC. The BFRCs presented higher bond strength to the dentin than the CTC in most of the evaluated conditions. The bleaching agent was not effective in whitening the stained restored teeth.

Comparative Study Regarding the Compressive Strength of Different Composite Resins Used for Direct Restorations

The aim of this study was to evaluate and to compare the compression behavior under identical mechanical tests, of three different composite resins, by determining Young�s modulus for compression, ultimate compressive strength and ultimate compressive strain. The studied materials were: Filtek Z250 Universal Restorative, Filtek Z550 and Filtek Bulk Fill Posterior Restorative (3M ESPE, St. Paul, MN, USA). Fifteen cylindrical samples, having 6 mm in height and 5 mm in diameter, were made from each material, using plastic molds. The samples were subjected to quantitative analysis of the compression behavior after mechanical tests. The fractured fragments of the samples were subjected to qualitative surface evaluation by scanning electron microscopy. Results were statistically analyzed using one-way analysis of variance (ANOVA) with Tukey�s post hoc test. Filtek Z250 had the lowest value of Young�s modulus for compression and the results were statistically significant (p[0.05) when compared to Filtek Bulk Fill Posterior Restorative and Filtek Z550. There were no statistically significant differences between all three materials regarding ultimate compressive strength (p]0.05). The lowest value for ultimate compressive strain was recorded for Filtek Bulk Fill.

Original and Repair Bulk Fracture Resistance of Particle Filler and Short Fiber-Reinforced Composites.

This study aimed to evaluate the original (OR) and repair (RR) fracture resistance of a semi-interpenetrating polymer network (semi-IPN)-based short fiber-reinforced composite compared to dimethacrylate-based composite materials by means of the V-notch test. Circular specimens (5×2 mm) with a centrally machined 90° V-shaped notch were prepared. Four bulk fill (Filtek Bulk Fill, Venus Bulk Fill, TetricEvo Ceram Bulk Fill, SDR), three microfilled hybrid (GC-Anterior, GC-Posterior, Z250), one nanofilled (SupremeXTE), and two short fiber-reinforced (Alert, everX Posterior) composites were selected. EverX Posterior was the semi-IPN material. Specimens (n=12/group) were either dry or water stored for 7 and 30 days, respectively, at 37°C and then loaded in two-point load until fracture. One-half of each tested specimen was used for the repair procedure. Repairing surfaces were diamond-bur ground, etched, and treated with silane containing universal adhesive (Scotchbond Universal) before repair. Three-way analysis of variance revealed a significant statistical difference between the groups ( p<0.05). The fracture resistance of dry-stored groups was greater than that of water-stored groups. The highest OR was observed for dry-stored Alert (23.4 N/mm), which significantly deteriorated in water (17.4 N/mm) ( p<0.05). The highest RR was observed for everX Posterior (20.0 N/mm), which did not deteriorate in water significantly (19.0 N/mm) ( p>0.05). The everX Posterior preserved the specimens' integrity at the final fracture load (ductile fracture), whereas all other materials fractured into two halves at the interface (adhesive failure). The only material that provided enhanced repair strength that was close to the original cohesive strength of the material was everX Posterior. The endurance of repaired restorations can be improved by using semi-IPN-based filling material.

Dynamic and Static Flexural Appraisal of Resin-based Composites: Comparison of the ISO and Mini-flexural Tests

The objective of this study was to determine the influence of specimen dimension and conditioning medium on the dynamic and static flexural properties of resin-based composites (RBCs). One conventional (Filtek Z350) and two bulk-fill RBCs (Filtek Bulk-fill and Beautifil-Bulk Restorative) were evaluated. Bar-shaped specimens with dimensions 25 × 2 × 2 mm (ISO flexural [IFT]) or 12 × 2 × 2 mm (mini-flexural [MFT]) were fabricated using customized stainless-steel molds, finished, measured, randomly divided into two groups, and conditioned in air or artificial saliva (SAGF) for seven days at 37°C. The specimens (n=10) were then subjected to dynamic and static three-point flexural testing. Data for storage modulus, loss modulus, loss tangent, flexural strength, and modulus were computed and subjected to t-test, analysis of variance/Tukey test, and Pearson correlation at a significance level of α = 0.05. For both IFT and MFT, significant differences in dynamic and static flexural properties were more prevalent between materials after storage in saliva. For both conditioning mediums, the strongest correlation between IFT and MFT was observed for flexural strength. While significant positive correlations were observed for all flexural properties with saliva, no significant correlations were detected for loss tangent and flexural modulus with air. For both IFT and MFT, storage in saliva appeared to be more discriminative than storage in air. As moderate to strong positive relationships exist between IFT and MFT for dynamic and static flexural properties, the mini-flexural test holds promise as a replacement for the ISO 4049 in view of its clinical relevance and greater efficiency.

Effect of fiber incorporation on the contraction stress of composite materials.

This study aimed to assess the effects of fiber incorporation on the contraction stress (CS), time to gelation (TG), and temperature rise (TR) features of two experimental resin-based composites (RBCs) in comparison to those of bulk-fill RBCs and conventional RBCs in simulated, clinically relevant cavities. CS over 300s, TG and TR were assessed by a stress-strain analyzer (SSA T80) in two cavity configurations (2 × 4 × 4mm3/4 × 4 × 4mm3/configuration value [Formula: see text] and [Formula: see text]) for two experimental RBCs, eight bulk-fill RBCs (EverX Posterior, Filtek Bulk Fill, SDR, SonicFill, Tetric EvoCeram Bulk Fill, Venus Bulk Fill, X-tra base, and X-tra Fill) and one RBC (Filtek Supreme XTE) by light curing (1200mW/cm2) (n = 10). The experimental materials used were based on EverX Posterior with modifications made to the fiber and filler content. Statistical analyses were performed via ANOVA; multiple pair-wise comparisons were performed via Tukey's test, and homogeneous subsets were identified ("multcomp" package, R). CS values ranged from 1.00 to 4.07MPa (2 × 4 × 4mm3) and from 0.97 to 2.49MPa (4 × 4 × 4mm3); TG values ranged from 1.31 to 4.05s (2 × 4 × 4mm3) and from 1.39 to 3.84s (4 × 4 × 4mm3). SDR values showed lowest stress values in both cavity configurations. The experimental composite with fibers presented significantly higher stress values than did the experimental composite without fibers. Bulk-fill RBCs showed lower levels of stress than did conventional RBCs. The incorporation of fibers had no positive impact on the CS and TG. Appropriate material selection may be essential to clinical success because certain RBCs exhibit higher CS, TG, and TR values.

Investigation of Two- and Three-Body Wear Resistance on Flowable Bulk-Fill and Resin-Based Composites

The purpose of the present study was to investigate two and three-body wear resistance and hardness of eighth kinds of modern bulk-fill and resin-based composite materials — Grandio, Estelite Flow, Filtek bulk-fill, Charisma, Clearfil, Ultimate, Quadrant, and G-aenial. All samples were kept in distilled water for one week, and their Vickers hardness was determined before two- and three-body wear tests. The mean volume loss of all specimens after the wear tests was determined by the 3D profilometry. In addition, a random specimen was selected from each test group and scanning electron microscope images were taken for an analysis of wear tracks. The surface morphology of the Clearfil and Ultimate composite materials was damaged severely, whereas Grandio and Charisma had a very smooth surface after two-body wear tests. The lowest mean volume loss was measured in micro-fill Grandio two-body and three-body wear tests. The Filtek bulk-fill and resinbased composites showed similar two- and three-body wear behavior. For the composite materials considered, correlations between the filler volume loss, Vickers hardness, and two- and three-body wear resistances were found to be insignificant.

The degree of conversion and class II cavity microleakage of different bulk fill composites placed with different restorative techniques

ObjectivesThe current study aimed to investigate the degree of conversion and microleakage of bulk fill composites placed using different restorative techniques. Materials and methodsFour types of resin composites were used: Incrementally-placed Filtek Z350 XT (INC), Filtek Bulk Fill Posterior Restorative (B), Filtek Bulk Fill Flowable (F), 3M ESPE, United States, and SonicFill (SON), Kerr, United States. For the degree of conversion (DC) test, five cylindrical samples were prepared for each group (5 mm diameter and 5 mm depth) (n = 5). Five groups, representing different material-technique combinations, were investigated: Group (INC) in which the incremental technique was used for packing Z350 composite (control), Group (B) in which Filtek Bulk Fill Posterior Restorative was placed as a one 5 mm deep increment, Group (FB-1C) in which Filtek Bulk Fill Flowable was used to fill 2 mm in the base of the mold followed by 3 mm Filtek Bulk Fill Posterior Restorative on top of it then both materials were cured simultaneously, Group (FB-2C) in which 2 mm of Filtek Bulk Fill Flowable was placed at the base of the mold and cured then the rest of the mold was filled with Filtek Bulk Fill Posterior Restorative followed by a final cure, and finally Group (SON) in which SonicFill composite was placed as a one 5 mm increment. The DC of both top and bottom surfaces of each sample was measured using Fourier-transform infrared spectroscopy-Attenuated Total Reflectance (FTIR-ATR). Forty-five extracted human premolars were used for the microleakage assessment. One or two class II slot cavities, with standardized dimensions, were prepared in each tooth. Each of the five investigated groups was represented by 11 cavities (n = 11). The cavities were filled using the same composite material-technique combinations used for the DC test. The restored teeth were thermocycled then immersed in 2% methylene blue solution for 24 h at 37 °C. Dye penetration was assessed by examining longitudinal mesio-distal sections through the restored teeth using a stereomicroscope at 25× magnification. The microleakage was scored using predetermined scoring criteria. The results were statistically analyzed. ResultsThe (INC) group showed significantly higher DC for the top surface than all bulk fill groups. No significant difference was found between the (INC), (FB-1C) and (FB-2C) groups regarding the DC of the bottom surface and the three groups had the highest DC while the (SON) group had the lowest DC values. Comparing the top and bottom surfaces of each single group, only the (FB-1C) and (FB-2C) groups showed a significant difference. No significant difference was found between the microleakage scores of the five investigated groups. ConclusionsConventional incrementally-placed composite has a higher DC compared to all bulk fill types regardless of the technique used for the bulk fill composite. The sonic-activated composite exhibits lower DC of the bottom composite surface than all other bulk fill composites. Regarding the microleakage, bulk fill composites, used with any of their possible techniques, do not perform any inferior compared to incremental composites.

Linear polymerization shrinkage of Bulk Fill resins

Abstract Objective: the objective of the present study was to analyze the polymerization shrinkage gap of different composite resins. Methods: four commercial brands (n=5) were tested: Z350 (3M/ESPE); Filtek Bulk Fill (3M/ESPE); Surefill (Dentsply); Xtra Base (Voco). Increments of composite resins were inserted into a circular metal matrix of 7 mm internal diameter and 4 mm high and pressed by two glass plates supported on polyester strips. After photoactivation with a Optilight Plus device (Gnatus), with light intensity of 1000 ± 10mW/cm2, the test samples were polished and 24h later, taken to the scanning electron microscope for analysis of the polymerization shrinkage gap, measured at 4 points in the sample (3, 6, 9, and 12 o’clock). The data were analyzed by analysis of variance (Anova one-way). Results: the highest mean of polymerization shrinkage gap was observed for Filtek Z350 (3M/ESPE), while the lowest mean of gap was found for Xtra Base (Voco) brand, with significant differences between the groups. Conclusion: the inorganic filler content and different associations in the organic matrices interfered expressively in the polymerization shrinkage gap. Keywords: Composite resins. Bulk Fill resins. Polymerization shrinkage.

One-year clinical evaluation of bulk-fill flowable vs. regular nanofilled composite in non-carious cervical lesions

The aim of this double-blind, randomized trial was to evaluate the 1-year clinical performance of a bulk-fill flowable and a regular nanofilled composite in non-carious cervical lesions (NCCLs). Twenty-two subjects with at least two NCCLs were enrolled in the study. A total of 89 restorations were performed by a single operator using Filtek Supreme (FS) Ultra Universal or Filtek Bulk (FB) Fill Flowable. A universal adhesive (Scotchbond™ Universal Adhesive) was used with a self-etching approach in dentin. The restorations were evaluated by two independent and previously calibrated examiners at baseline (7days), 6months and 1year, according to the USPHS modified criteria. Mann-Whitney U test was used to analyze the differences between composites and Wilcoxon signed rank test for comparisons between the baseline and follow-ups (α = 5%). One restoration was considered clinically unacceptable due to loss of retention after 6months in the FS group. FS presented statistically high scores for surface roughness when compared to FB after 1year (p < 0.05), but both were considered clinically acceptable. After 1year, the frequency of clinically unacceptable rates was 3.3% for anatomical form in the FB group, 1.1% for retention in the FS group, and 2.2% for marginal adaptation in both groups. All restorations, in both groups, presented score 0 over the 1-year period for marginal staining, postoperative sensitivity, and secondary caries. Both composite resins showed acceptable clinical performances for the restoration of NCCLs after 1year. Both bulk-fill flowable and regular nanofilled composites showed good clinical performances for the restoration of NCCLs after 1year.

Effect of light curing units on the polymerization of bulk fill resin-based composites

ObjectiveTo determine the potential effect of four different light curing units (LCUs) on the curing profile of two bulk fill resin-based composites (RBCs). MethodsFour LCUs (Bluephase 20i, Celalux 3, Elipar DeepCure-S and Valo Grand) were used to light cure two RBCs (Filtek Bulk Fill Posterior Restorative and Tetric EvoCeram Bulk Fill). The effective tip diameter, radiant power, radiant emittance, emission spectrum and light beam profile of the LCUs were measured. Knoop microhardness was measured at the top and bottom surfaces of RBC specimens that were 12-mm in diameter and 4-mm deep (n=5). The distribution of the spectral radiant power that was delivered to the surface of the specimen and the light transmission through the 4-mm thick specimens was measured using an integrating sphere. Two-way ANOVA and Tukey tests (α=0.05) were applied. ResultsThe Valo Grand produced the most homogeneous microhardness across the surfaces of the RBCs (p>0.05). When the Celalux 3, Bluephase 20i and Elipar DeepCure-S lights were used, the center of the specimens achieved greater hardness values compared to their outer regions (p<0.05). Approximately 10% of the radiant power delivered to the top reached the bottom of the specimen, although almost no violet light passed through 4mm of either RBC. A positive correlation was observed between the radiant exposure and microhardness. SignificanceThe characteristics of the LCUs influenced the photoactivation of the RBCs. The use of a wide tip with a homogeneous light distribution is preferred when light curing RBCs using a bulk curing technique.

Impact of dietary solvents on flexural properties of bulk-fill composites

ObjectiveThis study investigated the effect of dietary solvents on flexural strength and modulus of bulk-fill composites. Materials and methodsOne conventional composite (Filtek Z350 [FZ]), two bulk-fill composites (Filtek Bulk-fill [FB] and Tetric N Ceram [TN]) and a bulk-fill giomer (Beautifil-Bulk Restorative [BB]) were evaluated. Specimens (12 × 2 × 2 mm) were fabricated using customized stainless steel molds. Specimens were light-cured, removed from their molds, finished, measured and randomly divided into six groups. The groups (n = 10) were conditioned in the following mediums for 7 days at 37 °C: air (control), artificial saliva (SAGF), distilled water, 0.02 N citric acid, heptane, 50% ethanol–water solution. After conditioning, the specimens were rinsed, blotted dry, measured and subjected to flexural testing using a universal testing machine. Representative SEM images of the intact surfaces were obtained to appraise the degradation mechanism by dietary solvents. Data was subjected to statistical analysis using ANOVA/Tukey’s tests at significance level p < 0.05. ResultsSignificant differences in flexural properties were observed between materials and conditioning mediums. The highest flexural properties were usually obtained with conditioning in air (control) or heptane. Exposure to aqueous solutions generally reduced flexural properties of bulk-fill composites. ConclusionThe effect of dietary solvents on flexural properties of bulk-fill composites was material and medium dependent.

Influence of whitening dentifrices and mechanical brushing on color change and surface roughness of bulk fill resins

Abstract: The use of whitening dentifrices during oral hygiene may cause surface modifications such as color change (ΔE) and increase surface roughness (Ra) of composite resin. Aim: This study aimed to evaluate the effect of whitening dentifrices and mechanical brushing on color change and surface roughness of Bulk Fill (Filtek Bulk Fill - F) and (Aura Bulk Fill - A) composite resins. Materials and methods: Sixty cylindrical specimens were fabricated of each composite resin. After initial color evaluations (Konica Minolta CM-700d), with D65 standard illuminant, and the surface roughness (Surfcorder SE 1700, Kosalab), the specimens were assigned (n=10) according to the whitening dentifrice used: True White (T), Colgate Total 12 Professional Whitening (D), Luminous White Advanced (L). Specimens were submitted to mechanical brushing (10,000 cycles); new color and surface roughness evaluations were taken. Data were analyzed by ANOVA, Duncan test and Dunnet test were used to identify differences between groups (α=5%). Results: The results showed that the tooth brushing time promoted a significant increase in ΔE of the FT group. The FD group exhibited intermediate values of ΔE and was similar to all groups tested. There was a significant increase in the surface roughness of the AD and AT groups after the mechanical tooth brushing. Conclusion: The results showed no significant changes were observed in surface roughness for F groups after toothbrushing. It be concluded that the color change and surface roughness of the composite resins after toothbrushing are dependent on the interaction between the composition of the composite resin and the characteristics of the dentifrice.

COLOR, TRANSLUCENCY AND MASKING ABILITY OF A RECENTLY DEVELOPED BULK-FILL RESIN COMPOSITE

Objectives: To evaluate the color, translucency and masking ability of a newly developed bulk-fill resin composite with enhanced opacity. Materials and Methods: A3 shade composite discs (n=20/material) (Filtek bulk-fill; FB and Filtek bulk-fill One; FBOne) were prepared at 2 and 4 mm thickness (n=10/thickness). Three different backgrounds (white tile, black tile, and C4 shade porcelain) and the intrinsic color for each material were used to determine the translucency parameter (between white and black backgrounds), and to simulate oral cavity darkness (between the black background and the intrinsic color of resin composite), and the discolored tooth structure (between C4 shade porcelain and the intrinsic color of resin composite). Additionally, the chroma coordinates were measured for 2 mm thickness on the different backgrounds. Data were analyzed by Mann-Whitney U test, and Wilcoxon test as a post hoc for multiple comparisons (p< .05). Results: A clinically perceptible color difference (Δ E* > 1.74) was recorded between FB and FBOne. FBOne showed significantly higher TP values (p 2.7). FBOne showed a clinically acceptable (2 mm, ΔE* < 2.7) and un-perceptible threshold (4 mm, ΔE* < 1.74) for masking the discolored tooth substrate. Conclusions: FBOne is a promising bulk-fill resin composite showing an appropriate masking ability of the discolored tooth structure without interfering with its translucency

Viscoelastic Properties of Contemporary Bulk-fill Restoratives: A Dynamic-mechanical Analysis.

This study investigated the viscoelastic properties of contemporary bulk-fill restoratives in distilled water and artificial saliva using dynamic mechanical analysis. The materials evaluated included a conventional composite (Filtek Z350), two bulk-fill composites (Filtek Bulk-fill and Tetric N Ceram), a bulk-fill giomer (Beautifil-Bulk Restorative), and two novel reinforced glass ionomer cements (Zirconomer [ZR] and Equia Forte [EQ]). The glass ionomer materials were also assessed with and without resin coating (Equia Forte Coat). Test specimens 12 × 2 × 2 mm of the various materials were fabricated using customized stainless-steel molds. After light polymerization/initial set, the specimens were removed from the molds, finished, measured, and conditioned in distilled water or artificial saliva at 37°C for seven days. The materials (n=10) were then subjected to dynamic mechanical testing in flexure mode at 37°C and a frequency of 0.1 to 10 Hz. Storage modulus, loss modulus, and loss tangent data were subjected to normality testing and statistical analysis using one-way analysis of variance/Dunnett's test and t-test at a significance level of p < 0.05. Mean storage modulus ranged from 3.16 ± 0.25 to 8.98 ± 0.44 GPa, while mean loss modulus ranged from 0.24 ± 0.03 to 0.65 ± 0.12 GPa for distilled water and artificial saliva. Values for loss tangent ranged from 45.7 ± 7.33 to 134.2 ± 12.36 (10-3). Significant differences in storage/loss modulus and loss tangent were observed between the various bulk-fill restoratives and two conditioning mediums. Storage modulus was significantly improved when EQ and ZR was not coated with resin.

Influence of Polishing System on the Surface Roughness of Flowable and Regular-Viscosity Bulk Fill Composites.

This study evaluated the influence of polishing protocols on the surface roughness of flowable and regular bulk fill composites. Five bulk fill composites were tested: SureFil SDR Flow (SDR), Tetric EvoFlow Bulk fill (TEF), Filtek Bulk Fill Flowable (FIF), Tetric EvoCeram Bulk Fill (TEC), and Filtek Bulk Fill Posterior (FIP). Two polishing protocols were tested: Sof-Lex and Astropol. Astropol created a smoother surface for FIP (P < .05); however, the polishing protocol did not influence surface roughness on TEC (P > .05). SDR, TEF, and FIF exhibited rougher surfaces when polished. Sof-Lex created rougher surfaces for bulk fill composites. It was concluded that surface roughness was related to material composition rather than the polishing system.

The effect of Er:YAG laser and bulk filled composite type on marginal adaptation of class II cavities: an SEM analysis study

Purpose: To evaluate the effect of cavity preparation method (Er:YAG laser or diamond bur) and bulk-filled composite material type on marginal adaptation mesial occlusal (MO) class II cavities. Materials and Methods: Two-surface box cavities (4-mm proximal depth and 5-mm occlusal width) were prepared on 60 human mandibular molar teeth. Cavities were prepared using Er:YAG laser or diamond burs in an air-turbine hand-piece. All cavities were applied Single Bond Universal dentin bonding agent. The cavities were further subdivided into three subgroups according to the restorative material used; two bulk-filled composites [Filtek Bulk Fill Posterior (3M ESPE) and SonicFill 2 (Kerr)] and one traditional composite material Filtek Ultimate Universal Restorative (3M ESPE). Restorations were evaluated using scanning electron microscopy at ×200 magnification for their adaptation to the approximal margins of the tooth. Results were analyzed using the two-way ANOVA and Tukey Post Hoc Test (p < 0.05). Results: A total of 900 SEM figures were obtained from all groups. Filtek Bulk Fill Posterior, SonicFill 2, and Filtek Ultimate Universal Restorative exhibited statistically similar gapped margins. However, the lowest scores of gapped margins were observed with SonicFill 2 (4.22%). Conclusions: Completely gap-free margins were not obtained with any of the tested materials. Bulk-fill composite materials showed similar marginal adapatation compared with standard composite. Marginal adaptation of Er:YAG laser prepared cavities was more irregular and had more gaps, but was statistically similar to diamond bur-prepared cavities.

The effects of irradiance and exposure time on the surface roughness of bulk-fill composite resin restorative materials.

Objectives:To evaluate the surface roughness of 4 different bulk-fill resin-based composites cured using different irradiance levels.Methods:This in vitro study was performed in February 2017 to August 2017 at the College of Dentistry, King Saud University. Twenty-four specimens were prepared from each of the bulk-fill materials [Tetric N-Ceram (TNC), SonicFill (SF), Smart Dentin Replacement (SDR), and Filtek Bulk-Fill (FB)] using a brass metal mold, resulting in a total of 96 specimens, cured using a Bluephase N light curing unit. Half of the total number of specimens (N=48) were cured using high-power irradiance (1200 mW/cm2) for 20 seconds, while the remaining half (N=48) were cured using low power irradiance (650 mW/cm2) for 40 seconds. After 24 hours, baseline surface roughness of each specimen was analyzed using a profilometer, then polished using Sof-lex abrasive disks, and the surface roughness of all groups was assessed.Results:Post-polished SonicFill cured at high irradiance had the highest mean surface roughness (0.23±0.03), whereas pre-polished Smart Dentin Replacement (0.11±0.01) and SonicFill (0.11±0.02) cured at low irradiance had the lowest mean surface roughness.Conclusion:High curing irradiance (1,200 mW/cm2) had no positive influence on the surface roughness of Filtek Bulk Fill and Tetric N-Ceram bulk-fill RBCs compared with lower curing irradiance (650 mW/cm2). However, the difference of curing irradiance significantly affected the surface roughness in SDR and sonic fill RBCs.

Comparative evaluation of marginal seal integrity of three bulk-fill composite materials in Class II cavities: An In vitro study

Aim: The aim of this study is to compare marginal sealing of three different bulk-fill composite restorations of Class II cavities under in vitro conditions. Materials and Methods: Thirty human extracted pre-molars were divided into three groups of 10 each. Class II cavities were prepared and restored using Filtek Bulk Fill (Group I), Tetric N-Ceram Bulk Fill (Group II) and X-tra Fil Bulk Fill (Group III) composite materials. Depth of dye penetration along the lateral walls of each specimen was evaluated under stereomicroscope, and marginal gap was evaluated under scanning electron microscope. Statistical Analysis Used: In a one-way ANOVA study, statistical analysis will be done using non-parametric, Kruskal–Wallis rank-sum analysis and Chi-square test for categorical data. For all statistical analysis, probability levels of P < 0.05 will be considered statistically significant. Results: Stereomicroscopy showed no dye penetration in 90%, 70% and 30% of restorations in Groups I, II and III, respectively. The mean width of marginal gap (μm) was 1.691, 3.076 and 4.546 in Groups I, II and III, respectively. Conclusions: Under the limitation of in vitro study, Filtek Bulk Fill composite material showed least microleakage and better marginal adaptation.

Effect of Composite Polymerization Stress and Placement Technique on Dentin Micropermeability of Class I Restorations.

To investigate the effect of polymerization stress and insertion technique on dentin micropermeability of composites placed under pulpal pressure. One high-viscosity conventional (HC; Filtek Supreme Ultra; 3M Oral), one low-viscosity conventional (LC; Filtek Supreme Ultra Flowable; 3M Oral), one high-viscosity bulk fill (HBF; Filtek Bulk Fill Restorative; 3M Oral), and one low-viscosity bulk fill (LBF; Filtek Bulk Fill Flowable; 3M Oral) composite were evaluated. Polymerization stress was measured with materials bonded to acrylic rods in a universal testing machine (n = 5). Class I preparations were made in extracted molars, in which tooth roots were removed and the pulpal chambers cleaned. Preparations were coupled to a hydraulic device to simulate pulpal pressure during composite placement (n = 5). Conventional composites were placed in two horizontal increments, while bulk fill materials were placed in one, single increment. Fluid flow rate (µl/min) and dentin micropermeability (%) were monitored. The restoration interface was observed under confocal laser scanning microscopy. LC and LBF presented statistically significant higher polymerization stress than HC and HBF. Fluid flow rate and dentin micropermeability did not differ among the groups. However, different patterns of fluid infiltration and interface integrity were observed. HC and HBF presented well-sealed surrounding margins with small gaps along the pulpal wall, while HBF demonstrated more cracks in the adhesive layer. LC and LBF restorations had larger gaps along all bonded interfaces. No difference in polymerization stress was found when conventional and bulk fill composites with similar viscosities were compared. Neither polymerization stress or placement technique demonstrated a significant effect on dentin micropermeability. The incremental placement technique using a conventional, high-viscosity composite exhibited qualitatively better marginal integrity.

Effect of Water Sorption and Solubility on Color Stability of Bulk-Fill Resin Composite

The objective of this study is to compare the bulk-fill resin composite to a conventional one, as regards; water sorption, solubility, and their effect on color stability. This study was conducted using two types of composites: Bulk-fill composite (Filtek Bulk-Fill) and nanohybrid composite for control (Filtek Z250 XT). Specimens were prepared using a ring mold, 10 from each material. Specimens were desiccated, then weighed in a digital balance until a stable mass was acquired. For water sorption test, specimens were immersed in distilled water and placed in a lightproof incubator at 37 ± 1°C and the mass was measured weekly for 8 weeks. For solubility test, specimens were desiccated again in the desiccator until a stable mass was achieved. A spectropho-tometer was used to record the baseline color measurements prior to water immersion and weekly for 8 weeks. Bulk-fill composite showed higher water sorption value and lower water solubility values compared with that of the conventional one. No statistically significant difference was found for water sorption (p = 0.104) or water solubility (p = 0.098) between groups. The mean ΔE was lower in bulk-fill than conventional composite, and results showed a statistically significant difference (p = 0.009). Bulk-fill resin composite yielded better color stability and similar water sorption and solubility values. Bulk-fill resin composite can be used in esthetically concerned patients.