Tetric N-Ceram Bulk Fill Research Articles

Dureza superficial y resistencia a la compresión de materiales de restauración para dientes posteriores

Objective: To compare the in vitro surface hardness and compressive strength of three direct restorative materials for posterior teeth. Methodology: This is a cross-sectional comparative experimental in vitro study. The sample consisted of 60 cylinders divided into three groups of 20 samples: Tetric N-Ceram Bulk Fill resin, Alkasite Cention-N, and Giomer Beautifil II, which were prepared using a Teflon matrix that served as a mold to prepare cylinders with the restorative materials according to ISO 4049 standards. Surface hardness was measured using the Vickers hardness tester, while compressive strength was determined with the Universal Testing Machine, measured in Megapascals. Results: The obtained values for surface hardness showed that Beautifil II had the highest average with 66.36 Vickers, while Cention-N obtained 48.54 Vickers, and Tetric N-Ceram Bulk Fill 48.22 Vickers. Regarding compressive strength, the highest average was for Tetric N-Ceram Bulk Fill with 217.35 Megapascals, followed by Beautifil II with 195.83 Megapascals, and Cention-N with 187.55 Megapascals. Conclusion: Giomer Beautifil II presented the highest surface hardness, while Tetric N-Ceram Bulk Fill resin achieved the highest compressive strength. Conversely, Alkasite Cention-N obtained the lowest values for both mechanical properties.

Frecuencia de cepillado y uso de pasta dental con flúor en niños de 0 a 3 años de la parroquia hermano miguel del cantón cuenca

Objective: Oral hygiene in children aged 0 to 3 years is essential to prevent dental caries and promote healthy habits. Materials and methods: This was a quantitative, descriptive, observational and cross-sectional study. The sample consisted of 240 children aged 0 to 3 years. The information was collected through a questionnaire validated and approved by experts in the area. This instrument consisted of 16 questions about affiliation, type of oral hygiene input, frequency of tooth brushing and type of toothpaste that the father uses on the child. Data was processed by the statistical software SPSS in its version 26. Results: TMost of the sample was made up of girls (51.7%). The most reported frequency of tooth brushing was twice a day (48.8%). The most used fluoride toothpaste is 1000-1100 PPM (35.8%). 40% of one-year-old children use the amount of toothpaste equivalent to 1 grain of raw rice. The most common daily brushing was twice a day (54.8%) in households with incomes below $400. Conclusion: Most of the children aged 0-3 years in the Hermano Miguel Parish brush their teeth twice a day and use fluoride toothpaste of 1000-1100 PPM. Conclusion: Giomer Beautifil II presented the highest surface hardness, while Tetric N-Ceram Bulk Fill resin achieved the highest compressive strength. Conversely, Alkasite Cention-N obtained the lowest values for both mechanical properties.

Surface Roughness and Color Stability of Conventional and Bulk-Fill Resin Composite with S-PRG Fillers After Coffee Exposure: An in-vitro Study.

This study aimed to evaluate the in vitro effects of coffee exposure on the color and roughness of conventional and bulk-fill resin composites, with and without surface pre-reacted glass-ionomer (S-PRG) filler. Forty-eight cylindrical samples (Ø6 mm × 2 mm) were prepared and categorized as follows (n = 12 per group): conventional nano-hybrid (Tetric N-Ceram, Ivoclar); nano-hybrid with S-PRG filler (Beautifil II, Shofu); bulk-fill (Tetric N-Ceram Bulk Fill, Ivoclar); and bulk-fill with S-PRG filler (Beautifil Bulk Restorative, Shofu). The samples were assessed for surface roughness (Ra, μm), color coordinates (CIE Lab), and overall color change (ΔEab, ΔE00). Measurements were taken at baseline and after 7 days of coffee immersion (pH = 4.95). Data were analyzed using generalized linear models, Kruskal-Wallis, Dunn, and paired Wilcoxon tests (α = 0.05). After the coffee exposure, all resin composites exhibited a significant decrease in L* (towards black), an increase in a* (towards red), an increase in b* (towards yellow), and a higher Vita color score (p < 0.05). Tetric N-Ceram demonstrated the lowest roughness values post-exposure; however, a significant increase in roughness over time was observed only for Tetric N-Ceram Bulk Fill (p < 0.05). For ΔEab, Beautifil Bulk Restorative and Tetric N-Ceram showed higher values compared to Beautifil II. For ΔE00, a significant difference was noted between Beautifil Bulk Restorative and Beautifil II (p < 0.05). Resin composites with S-PRG fillers exhibited similar pigmentation dynamics to conventional composite but showed greater surface roughness after exposure to coffee. Considering the S-PRG materials, the bulk-fill version is more susceptible to staining.

Physical and Mechanical Properties of Bulk-fill Resin Composites Submitted to Additional Polymerization for Use in Semi-direct Restorations.

Physical and mechanical properties of high-viscosity bulk-fill resin composites submitted to additional polymerization for semi-direct use were evaluated. Filtek Z350 XT, Aura Bulk Fill, Beautifil Bulk Restorative, Filtek One Bulk Fill Restorative, and Tetric N-Ceram Bulk Fill were submitted to additional polymerization to evaluate sorption, solubility, surface microhardness, surface roughness before and after simulated brushing, color stability after coffee staining, flexural strength, elastic modulus, and modulus of resilience. Filtek Z350 XT and Filtek One Bulk Fill Restorative showed higher sorption values, while Aura Bulk Fill showed higher solubility (p<0.0001). Microhardness values were significantly higher for Filtek Z350 XT (p<0.0001). Roughness increased after wear for all resins (p<0.05). All resins exhibited staining, with significantly higher ΔEab, ΔE00, and ΔWID values observed for Beautifil Bulk Restorative (p<0.0001). Flexural strength values were higher for Filtek Z350 XT and Filtek One Bulk Fill Restorative in comparison with the others (p<0.0001). Filtek One Bulk-Fill had higher elastic modulus and modulus of resilience values (p<0.0001). Physical and mechanical properties varied according to the composition. None of the bulk-fill resins showed surface microhardness and roughness properties after brushing similar to or superior to those of the conventional type. Color stability after staining depended on resin composition, with Beautifil Bulk Restorative showing more intense staining.

Comparative evaluation of microleakage in Class II cavities restored with snowplow technique using flowable or preheated packable bulk-fill composite resin as gingival increment by dye extraction method: An in vitro study.

One of the undesirable characteristics of dental composite resin is the polymerization shrinkage and the associated microleakage. The snowplow technique of placement and the preheating of the composite resins are methods to minimize microleakage. The aim of this study was to comparatively evaluate microleakage in Class II cavities restored with snowplow technique using either preheated packable or flowable bulk-fill composite resin. Fifty sound first molars were selected. Class II mesio-occlusal box preparations were made. The test specimens were randomly divided into two groups. Group 1: Tetric N-Flow Bulk Fill and Tetric N-Ceram Bulk Fill co-cured in snowplow technique. Group 2: Tetric N-Ceram Bulk Fill preheated to 60°C and Tetric N-Ceram Bulk Fill co-cured in snowplow technique. Restored teeth were processed for dye extraction. Mann-Whitney U-test was applied to compare the microleakage between the groups. Results indicate that specimens in Group 2 showed lower microleakage (median 0.041750) when compared to specimens in Group 1 (median 0.059400). The results imply that the preheated packable bulk-fill composite resin showed less microleakage as compared to flowable composite while restoring Class II cavities by the snowplow technique.

The Impact of Modeling Liquids on Surface Roughness and Color Properties of Bulkfill Resin Composites After Simulated Tooth Brushing: An in Vitro Study. Part I.

To evaluate the effect of different modeling agents on color changes, surface roughness, and translucency parameters over time in Bulkfill resin composites. Sixty specimens were prepared using three Bulkfill resin composites (Tetric N-Ceram Bulkfill, Filtek One Bulkfill and Opus Bulkfill) and three modeling agents (Wetting Resin, Optibond FL and Ambar APS). All specimens were subjected to a simulated tooth-brushing (Baseline, 50.000 cycles, 100.000 cycles), and surface roughness was measured at each interval. Surface topography was evaluated. The translucency parameter and color changes were assessed after 24-h, 7-, 14- and 30-day immersion in water, wine, and coffee. Data was analyzed using ANOVA and Bonferroni test. All specimens increased roughness after simulated tooth-brushing (p < 0.05). Wetting Resin decreased roughness on Tetric N-Ceram Bulkfill (p < 0.05). The translucency parameter remained unaltered for all groups. All groups changed color after 30-days of immersion in wine and coffee (p < 0.05). Ambar APS and Wetting Resin on Tetric N-Ceram Bulkfill showed higher color changes when immersed in coffee (p < 0.05). The use of modeling agents does not jeopardize translucency properties but may affect surface roughness and color properties of Bulkfill resin composites depending on their composition. The findings of this study suggest that surface roughness and color properties are affected by the differences in the composition between modeling agents and Bulkfill resins composites.

The 24 months clinical evaluation of class II bulk fill composite restorations

Background: Resin Composite materials are widely used in daily clinical dentistry because of their moderate cost compared with ceramics, easy placement, adequate esthetics, ability to bond with enamel and dentine, and physico-chemical properties. Bulkfill composite materials were introduced to reduce chairside time. These materials have properties such as optimal bond strength, decreased polymerization shrinkage, and reduced cuspal deflection. This in-vivo study compared the clinical performance of three different class II resin composite restorations. Methods: Seventy-one patients (41 females and 30 males) aged 20–43 years with at least three approximal caries were included in the present study. Two hundred twenty-three teeth with approximal caries were restored with two bulk-fill composites (Tetric-N Ceram Bulk fill [TEC], Filtek Bulk Fill [FB]) and a posterior resin composite (Gradia Direct Posterior [GDP]). Two experienced dentists clinically evaluated the restorations with a 5x magnification loupe using the modified United States Public Health Service (USPHS) criteria at baseline and at 24 months. Results: The chi-square test was performed for statistical analysis. The cumulative retention rate for all restorations at 24 months was 90.5%. Retention loss was observed for three TEC (6.1%), four FB (8.2), and seven GDP (14%) restorations. There was no statistically significant difference among the three resin composite restoration groups in color match, marginal adaptation, surface roughness, marginal discoloration, anatomical form, and secondary caries criteria (P&gt;0.05). Conclusion: Bulk-fill composite restorations in class II slot cavities have the same clinical results as traditional posterior composite restorations.

Effect of a 3-second Off-label Exposure on the Depth of Cure of Eight Resin-based Composites.

This study evaluated the depth of cure (DoC) of eight resin-based composites (RBCs) photocured using one multipeak light-curing unit (LCU) on the standard output setting for the manufacturer's RBC recommended exposure time and at a higher irradiance for 3 seconds. Three conventional RBCs: Tetric EvoCeram (Evo), Tetric N-Ceram (Cer), Tetric Prime (Pri); and five bulk-fill: Tetric N-Ceram Bulk Fill (CerBF), Opus Bulk Fill APS (OpusBF), Opus Bulk Fill Flow APS (OpusF), Tetric PowerFill (PFill) and Tetric PowerFlow (PFlow) were examined. Only PFill and PFlow are formulated to be photocured in 3 seconds. The RBCs were packed into a metal mold and photocured using a Bluephase PowerCure LCU for the RBC manufacturer's recommended exposure time on the standard mode and using the 3-second high irradiance mode. After photocuring, the specimens were immersed in a solvent for 1 hour. The length of the remaining RBC was measured and divided by 2. Data were analyzed using two-way analysis of variance (ANOVA) followed by the Tukey post hoc multiple comparison test (α=0.05). There was no significant difference in the DoC values for PFill and PFlow when photocured using the 3-second high irradiance protocol compared to the lower irradiance standard mode protocol. All other RBCs had significantly lower DoC values (p<0.001) when photocured off-label using the 3-second high irradiance mode. Of the eight RBCs tested, only PFill and PFlow achieved the same DoC when the high irradiance 3-second curing method was used compared to when their longer lower irradiance protocol was used.

Effect of Polywave and Monowave Light Curing Units on the Microtensile Bond Strength and Failure Types of Different Bulk-Fill Resin Composites: An in vitro Study.

This study aimed to evaluate the effects of polywave and monowave light-emitting diode curing units on the microtensile bond strength and failure types of three bulk-fill resin composites. This in vitro experimental study was performed on 180 microbars obtained from human third molars and were distributed into 12 groups according to the type of bulk-fill resin composite and the light-curing unit. Third molars were restored using Filtek One Bulk Fill Restorative, Tetric® N-Ceram Bulk Fill, and Opus Bulk Fill resin composites was light-cured with Elipar Deep Cure L and Valo in three modes: standard, high power, and extra power. Subsequently, microtensile analysis was carried out with a universal testing machine and the type of failure with an optical stereomicroscope. For statistical analysis, the Kruskal-Wallis H-test was used, with the Bonferroni post hoc test and Fisher's exact test, considering a significance of p<0.05. There were significant differences in the microtensile bond strength between the Filtek One Bulk Fill restorative and Opus Bulk-Fill (p = 0.042) when light was cured with the polywave unit at standard power. On the other hand, the Filtek One Bulk Fill Restorative and Opus Bulk Fill resins showed significant differences in microtensile bond strength when light was cured with the monowave unit compared with the polywave unit (p<0.05). The presence of alternative photoinitiator systems that are more reactive than camphorquinone produced higher microtensile bond strength in Tetric N-Ceram Bulk Fill and Opus Bulk Fill resins when light-cured with a high and standard polywave unit, respectively, compared to Filtek One Bulk Fill resins. Finally, Tetric N-Ceram Bulk Fill and Opus Bulk Fill resins had the highest percentage of mixed failures, while Filtek One Bulk Fill resin had adhesive failures, which was related to its lower microtensile bond strength.

Polymerization efficiency of different bulk-fill resin composites cured by monowave and polywave light-curing units: a comparative study.

The objective was to evaluate the polymerization efficiency of different bulk-fill resin-based composites cured by monowave and polywave light-curing units, by assessment of the degree of conversion and Vickers microhardness at different depths. Two commercially available bulk-fill resin-based composites were used: Filtek One Bulk Fill Restorative (3M ESPE) and Tetric N-Ceram Bulk Fill (Ivoclar Vivadent). The light-curing units utilized were two LED light-curing units: a monowave LED light-curing unit (BlueLEX LD-105, Monitex) and a polywave LED light-curing unit (Twin Wave GT-2000, Monitex). For each test, 20 cylindrical specimens (4 mm diameter, 4 mm thickness) were prepared from each bulk-fill resin-based composite using a split Teflon mold. Ten specimens were light-cured by the monowave light-curing unit and the other ten were light-cured by the polywave light-curing unit according to the manufacturer's recommendations. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) was used to assess the degree of conversion, and a Vickers microhardness tester was used to assess Vickers microhardness. Statistical analysis was performed using three-way ANOVA and Tukey post-hoc tests (P < .05). The degree of conversion and Vickers microhardness in bulk-fill resin-based composites containing only camphorquinone as photoinitiator were similar when cured with either monowave or polywave light-curing units. However, bulk-fill resin-based composites containing a combination of photoinitiators exhibited significantly higher degree of conversion and Vickers microhardness when cured with a polywave light-curing unit. Although all groups showed statistically significant differences between the top and bottom surfaces regarding degree of conversion and Vickers microhardness, all of them showed bottom/top ratios > 80% regarding degree of conversion and Vickers microhardness. The polywave light-curing unit enhanced the polymerization efficiency of bulk-fill resin-based composites especially when the latter contained a combination of photoinitiators, but does not prevent the use of a monowave light-curing unit.

Two-year clinical performance of dual- and light-cure bulk-fill resin composites in Class ӀӀ restorations: a randomized clinical trial

ObjectiveThis study aimed to compare the clinical performance of dual- and light-cure bulk-fill resin composites (BFRCs) in Class ӀӀ restorations after 2 years.Materials and methodsA double-blinded, prospective, randomized clinical trial (RCT) was conducted following the CONSORT (Consolidated Standard of Reporting Trials) guidelines. Forty patients were enrolled in the study. Each patient received three compound Class ӀӀ restorations. One dual-cure (Fill-Up; Coltene Waledent AG) and two light-cure (QuiXfil; Dentsply, and Tetric N-Ceram Bulk Fill; Ivoclar Vivadent) BFRCs were used for 120 Class ӀӀ restorations. A universal adhesive (ONE COAT 7 UNIVERSAL; Coltene Waledent AG) was used with all restorations. Restorations were clinically evaluated after 1 week (baseline), 6 months, 12 months, 18 months, and finally after 24 months using the FDI World Dental Federation (FDI) criteria. The Kruskal–Wallis test was used for comparison between BFRCs groups at baseline and at each recall period, and the Wilcoxon signed-rank test was used for comparing different follow-up times of each BFRC to baseline. The level of significance was set at p < 0.05.ResultsAll BFRCs restorations showed only minor changes and revealed no statistically significant differences between their clinical performance for all evaluated parameters at all recall periods; also, there was no statistically significant difference between all recall periods and baseline for all evaluated parameters.ConclusionThe two-year clinical performance of dual-cure BFRC was comparable to light-cure BFRCs in Class ӀӀ restorations.Clinical relevanceDual- and light-cure BFRCs showed excellent clinical performance in Class ӀӀ restorations after a 2-year clinical follow-up.

Evaluation of fracture resistance of maxillary premolars of different geometrical cavities restored with different composite resins incorporated with chitosan nanoparticles.

Composites with 0.2% chitosan nanoparticles (CSN) are used recently; however, this combination needs to be studied in different cavity designs. The aim of the study was to compare the fracture resistance of maxillary premolars with different cavity geometries restored with different types of composite resins incorporated with 0.2% CSN. About 130 extracted human single-rooted maxillary premolars were embedded in acrylic molds 2 mm below cementoenamel junction, divided into five groups for cavity preparations of standardized dimensions. Group 1: (control) intact teeth (n = 10), Group 2: Class I cavities (n = 40), Group 3: Class II mesio-occlusal (MO) (n = 40), Group 4: Class II mesio-occluso-distal (MOD) (n = 40). Groups 2, 3, and 4 were subdivided into four subgroups for composite restoration; A: Neo spectra ST-Universal (NST); B: Tetric N-Ceram Bulk-fill (TNC); C: NST + CSN; and D: TNC + CSN and tested for fracture resistance using universal testing machine. One-way analysis of variance and post hoc Tukey's tests were used for data analysis (P ≤ 0.05). In all groups, the highest fracture resistance was found in MOD cavities, followed by MO and least in Class I cavities. Subgroup D (TNC with CSN) showed the highest fracture resistance in all groups (P ≤ 0.05). Tetric N-Ceramic bulk fill with 0.25% CSN showed high fracture resistance in cavities with different geometries.

Influence of Light-Curing Time and Increment Thickness on the Properties of Bulk Fill Composite Resins With Distinct Application Systems.

The objective of this study was to evaluate the influence of light-curing time and increment thickness on the microhardness and degree of conversion (DC) of bulk fill composite resins with different application systems. Translucency parameter (TP) was also measured. Specimens of resin composites were prepared in a circular matrix using a single increment with different thicknesses (2, 4, and 6 mm) and light-cured with distinct times (10, 20, and 40 s). The materials tested (n = 5 pergroup) were Filtek One (FO) bulk fill, Tetric N-Ceram (TC) bulk fill, SonicFill 3 (SF), VisCalor (VC) bulk. After 24 h, Knoop microhardness (KN) was measured, and the bottom/top ratio (B/Tratio) was calculated. The DC was measured using Fourier transformed infrared (FTIR) spectroscopy. The TP was assessed in additional specimens with 1 mm thick (n = 5). The data were statistically analyzed with analysis of variance (ANOVA) and Tukey's tests (5%). Significant differences were observed for all factors, for both B/Tratio and DC (p < 0.05). The higher increment thickness and the lower curing times resulted in lower B/Tratio and DC means. The VC and TC resins exhibited the overall higher B/Tratio, and the highest TP. SF presented the lowest values of B/Tratio and DC, with compromised polymerization at 6 mm depth. TP (means ± SD) were FO (12.85 ± 1.0)1, SF (15.62 ± 0.73)2, TC (20.32 ± 0.49)3, and VC (20.53 ± 0.73)3. We concluded that the greater the thickness of the increment, the lower the DC. Higher light curing times resulted on increased DC of the tested composites. The higher translucent materials VC and TC showed the greater B/Tratio; and FO resin exhibited the higher DC values.

Influence of compressive forces and aging through thermocycling on the strength of mono incremental dental composite resins

Understanding dental composite resins' physical and mechanical properties is vital for advancing dental materials science, enhancing durability, and improving patient care. The present study aims to quantitatively investigate the impact of compressive forces and thermocycling aging on the strength of mono incremental dental composite resins, focusing on three materials: 3M Filtek One Bulk Fill, Opus Bulk Fill APS A2 from FGM, and Tetric N-Ceram Bulk Fill VIA from Ivoclar Vivadent. Using a mixed quasi-experimental approach, 84 samples were divided into a control group and an experimental group, comprising 14 samples of each material. The samples underwent a thermocycling process involving temperature cycles between 5°C, 37°C, and 55°C, totaling 10,800 cycles, simulating one year of aging. Subsequently, compressive strength tests were conducted using a universal press to identify the fracture point of the material and calculate its strength. Our results reveal differences in the material before and after thermocycling; however, these differences were not statistically significant concerning strength. Thus, it is concluded that one year of thermocycling aging does not induce substantial changes in the resin that would compromise its strength. Future research should consider extended thermocycling tests spanning multiple years to pinpoint the potential onset of issues affecting material strength durability. Keywords: compressive strength, dental composite resins, thermocycling, aging, mono incremental.

5-year clinical performance of posterior bulk-filled resin composite restorations: A double-blind randomized controlled trial

ObjectivesThe aim of this double-blind, and randomized controlled clinical trial was to evaluate the 5-year clinical performance of posterior resin composite restorations placed with the incremental filling technique [IF] or the bulk-fill technique [BF]. Two different adhesive systems were used: etch-&-rinse (ER) or self-etch (SE). MethodsPosterior dental teeth of 72 participants (n = 236), with a cavity depth of at least 3 mm, were randomly divided into four groups. Restorations were applied with either Tetric N-Bond or Tetric N-Bond SE. The composite resin Tetric N-Ceram Bulk-Fill was placed either with IF or BF. Restorations were evaluated using FDI criteria at baseline and after 1, 2, 3, 4, and 5 years. Statistical analysis was performed using the Wilcoxon Signed rank test (a=0.05). ResultsTwo hundred and four restorations were evaluated after 5 years. Eleven restorations were considered 'failed', ten due to fracture (4 IF and 6 BF) and one due to secondary caries (IF). The annual failure rate was 1.2% for BF and 1% for IF (p = 0.35). When comparing BF and IF, no significant differences were found for any of the parameters evaluated (p > 0.05). Regarding the adhesive systems, 44 and 51 restorations showed minor problems in terms of marginal adaptation and staining, with significantly more marginal discoloration when the self-etch adhesive was used (p = 0.002). SignificanceThe bulk-fill restorative technique showed good clinical behavior compared to the incremental filling technique, especially when using an etch-&-rinse adhesive, after 5 years of clinical evaluation.

Cuspal Deflection and Marginal Integrity of Class II Cavities Restored with Bulk-fill Resin Composites

Objective: This laboratory study aims to assess the cuspal deflection, adaptation, and marginal sealing of premolars restored with bulk-fill resin composites. Methods: Fourty-four premolars received class II preparations (distal and mesial boxes located 1 mm above and 1 mm below the cementoenamel junction, respectively). The teeth were distributed into four groups according to the resin composite used for restoration (n=11): G1 (control): Filtek Z250 XT; G2: Filtek Bulk-Fill; G3: Tetric N-Ceram Bulk-Fill; G4: Aura Bulk-Fill. A digital micrometer was used to measure the cuspal deflection before and after the restorative procedures. Replicas in epoxy resin of the restored teeth were achieved before and after thermal cycles. The cervical margins were observed by SEM at 200x magnification to obtain the percentage of continuous margins (%CM). After thermal cycles, the samples were immersed in a silver nitrate solution, and the microleakage was analyzed in the cervical margins. Results: ANOVA showed no significant differences in the cuspal deflection and %CM among the resin composites. Student’s t-test showed a significant decrease in the %CM after thermal cycles for all resin composites at the cervical margin in dentin. There was higher microleakage at the dentin margin for all the resin composites. Conclusion: Bulk-fill resin composites had comparable behavior to a conventional composite in regard to the cuspal deflection, adaptation, and marginal sealing parameters.

Cuspal Deflection and Marginal Integrity of Class II Cavities Restored with Bulk-fill Resin Composites

Objective: This laboratory study aims to assess the cuspal deflection, adaptation, and marginal sealing of premolars restored with bulk-fill resin composites. Methods: Fourty-four premolars received class II preparations (distal and mesial boxes located 1 mm above and 1 mm below the cementoenamel junction, respectively). The teeth were distributed into four groups according to the resin composite used for restoration (n=11): G1 (control): Filtek Z250 XT; G2: Filtek Bulk-Fill; G3: Tetric N-Ceram Bulk-Fill; G4: Aura Bulk-Fill. A digital micrometer was used to measure the cuspal deflection before and after the restorative procedures. Replicas in epoxy resin of the restored teeth were achieved before and after thermal cycles. The cervical margins were observed by SEM at 200x magnification to obtain the percentage of continuous margins (%CM). After thermal cycles, the samples were immersed in a silver nitrate solution, and the microleakage was analyzed in the cervical margins. Results: ANOVA showed no significant differences in the cuspal deflection and %CM among the resin composites. Student’s t-test showed a significant decrease in the %CM after thermal cycles for all resin composites at the cervical margin in dentin. There was higher microleakage at the dentin margin for all the resin composites. Conclusion: Bulk-fill resin composites had comparable behavior to conventional composites in regard to the cuspal deflection, adaptation, and marginal sealing parameters.

An In-depth Analysis of the Effects of Preheating Three Different Composite Resin Systems at Two Different Temperatures on Their Microhardness

Abstract Background: Composite restorations often have inferior physical properties compared to natural enamel and dentin, leading to early failure. Preheating the traditional composite before its placement and curing seems to enhance all its physical characteristics magically. The objective of the current research was to assess the impact of preheating on the surface microhardness of commonly used composite resin materials, specifically FILTEK P60, FILTEK Z250XT, and Tetric-N-Ceram Bulk fill. Materials and Methods: The resin composite tubes were either left at the ambient room temperature (24°C ± 1°C) or preheated in a commercial preheating device to 50°C and 60°C for 40 min. By inserting uncured preheated composite resin into class II Mseio-Occluso-Distal (MOD) cavities with specifications of 2 ± 0.3 mm axial height, 2 ± 0.3 mm pulpal depth, parallel proximal walls with a 3 ± 0.3 mm buccolingual width, 1.5 ± 0.3 mm gingival width, and an occlusal isthmus width equal to one-third of the intercuspal distance from composite resin tubes, a total of 99 class II MOD cavities on premolars were established. Each specimen’s Vicker’s hardness number (VHN) was determined. The gathered information was examined utilizing a two-way ANOVA and Tukey’s post hoc test with a significance threshold of 0.05. Results: When preheated to the temperatures of 50°C and 60°C, a remarkable rise in the mean Vickers hardness numbers (VHNs) of all the resin composites compared to those maintained at the room temperature (P &lt; 0.05) was seen. The mean VHNs at the room temperature for FILTEK P60, FILTEK Z250XT, and Tetric-N-Ceram were 47.27 ± 9.08, 59.63 ± 1.56, and 75.69 ± 0.80, respectively, with a significant variation between all of them (P &lt; 0.05). The mean VHNs were, respectively, 108.45 ± 2.42, 103.45 ± 1.29, and 113.00 ± 4.35 at 50°C, with a significant variation between them all. At 60°C, the mean VHNs were, respectively, 121.09 ± 1.30, 128.00 ± 0.89, and 135.00 ± 2.04, with a significant variation between all of them (P &lt; 0.05). Conclusion: The surface microhardness of all investigated composite resins was greatly increased by preheating, with Tetric N-Ceram Bulk Fill showing the greatest value at a preheating temperature of 60°C.

Evaluation of the Microhardness of Different Types of Bulk Fill Resins

The constant search for the ideal restorative material causes the new formulations to aim for an increase of 4 to 5 mm, getting an improvement of its mechanical properties, for example, the organic and inorganic matrix of other materials. With this, the objective of the present study was to evaluate the microhardness of different brands of bulk fill resin. In order to perform the research, 30 specimens were prepared, with group 1 with 10 specimens of the conventional composite resin Opallis (FGM). Group 2 with 10 specimens of Oppus Bulk Fill composite resin (FGM). And group 3 with 10 specimens of the Tetric N-Ceram Bulk fill resin (Ivoclar Vivadent), all made from a preset silicon matrix. Each group was photopolymerized on the upper surface at the time indicated by the manufacturer, stored in an oven with distilled water under 37 ° C for 24 hours. After this period, they were measured with a digital caliper and submitted to the Vickers microhardness test at 5 random points on the upper surface. The values recorded by the microdurometer were taken to the statistical analysis using ANOVA test with Tukey post-test, in which it showed a statistical difference between Bulk fill Tetric N-Ceram (Ivoclar Vivadent) and Opallis (FGM) with p value&lt;0.001, and a statistical difference between Bulk Fill Tetric N-Ceram (Ivoclar Vivadent) and Opus Bulk Fill (FGM) with a p value of 0.001. There was no difference between Opallis and Opus Bulk fill (FGM). It was concluded that Bulk Fill Tetric N- Ceram resin (Ivoclar Vivadent) obtained a lower microhardness when compared to Opallis (FGM) and Opus Bulk Fill (FGM) resins.

A Laboratory Study of the Effect of pH on Solubility of Bulk-Fill and Conventional Composites

Aim: Factors such as the low pH of acidic foods and beverages can affect long-term clinical success of restorative materials in the oral cavity. The aim of this study was to compare the solubility of Bulk-fill and Conventional Nano-Hybrid Resin Based Composites (RBCs) in different solutions. Material and Methods: A total of 60 cylindrical specimens were prepared from two RBCs (Tetric N-Ceram, Tetric N-Ceram Bulk-fill) and their constant weight was measured. The specimens were divided into six groups ( N = 10) in accordance with RBC type and pH solution (solution 1, 2, 3 with pH = 2.5, 5, 7, respectively), and were immersed in desired solutions for 30 days. Then they were weighed again and solubility levels of the specimens were calculated according to ISO 4049. Data were analysed by two-way ANOVA. The test power was considered at 80%. Results: The type of RBC had no significant effect on solubility; while the effect of PH was significant. Solution 1 caused significantly the highest solubility. No statistically significant differences were found among other groups. Conclusions: Considering the limitations of the laboratory investigations, it was concluded that solubility rate of Bulk-fill and Conventional RBCs was higher in solutions with lower pH. There was no difference among the RBCs. However, the solubility rates of all groups are within the clinically normal range.