Tetric EvoCeram Research Articles

Proteomic Analysis of Fibroblasts Exposed to Resin Composite Release.

To investigate the potential effects of products released by a resin composite on the proteome of human gingival fibroblasts. Fifteen resin composite cylinders of a Bis-GMA-based resin composite (Tetric EvoCeram, Ivoclar) were made and placed in a culture medium for 24h. Then, 30mL of this medium was placed for 72h in contact with human gingival fibroblasts and a second control group consisted of cells placed in culture medium only. Afterward, cells were collected, washed, and their proteins extracted. Three two-dimensional electrophoresis were performed per condition. Image analysis of the gels was carried out to highlight the differential protein spots. These spots were then analyzed by an ESI/qTOF mass spectrometer. Finally, specific databases provided protein identification, their interactions, and the pathways where they are implicated. Delta2D software allowed the detection of 21 spots of different proteins. The MASCOT identified 28 proteins. Five proteins from four spots were upregulated, 23 proteins from 17 spots were downregulated. The UniProt database showed that all these proteins were involved in cellular architecture, structural modifications and quality control of proteins, cellular homeostasis, and metabolic pathways. The STRING database revealed the interactions between the regulated proteins. The GO enrichment analysis showed that 19 pathways were affected. The products released from the resin composite tested led to changes in the fibroblast proteome. Under the conditions of this study, resin composite released products can cause early adverse effects on cells, but without complete inhibition of their cellular functions.

Surface and bulk viscoelastic stability of solvent-stored bulk-fill resin-based composite

ObjectiveInvestigate the effect of solvent-storage on surface hardness and bulk creep of fast photo-cured bulk-fill resin-based composite (RBC) compared to conventionally irradiated bulk-fill RBCs. MethodsThree bulk-fill RBCs were studied: Tetric® PowerFill (fast photo-cured bulk-fill RBC) (TPF), Tetric EvoCeram® (EVO), and GrandioSO® x-tra (GSOx) (conventional). Disk-shaped specimens of clinically realistic thickness (4 mm) were prepared from each material for: Group A: surface measurements (18 mm diameter) and Group B: 4 mm diameter for bulk compressive creep measurements. Group A disks were light-cured from the upper ‘occlusal’ surface for either 3 s or 20 s according to the manufacturer’s recommendation. Martens hardness (HM) of both top and bottom surfaces of each specimen were measured. Group B: 4 × 4 mm cylindrical specimens were fully cured to measure bulk creep (CB). A 20 MPa static compressive stress was applied for 2 h, followed by 2 h of unloading. Strain deformation was recorded continuously for 4 h. Both Martens and bulk creep studies were performed under the following storage conditions at 37 °C: (i) dry at 24 h post curing (baseline), and (ii) after 7 and 30 d of storage in two different media: distilled water (DW) and 75 % ethanol/water (75 % E/W). ResultsAt baseline, HM for all materials ranged from 587 to 439 N/mm2 (top) and 398 to 342 N/mm2 (bottom). After 30 d of solvent-storage, more pronounced HM changes were observed, with the bottom surface being more affected. Normalised HM for TPF decreased by 44 % after 30 d in 75 % E/W. Maximum creep strain ranged from 1.1 % to 2.1 % at baseline, and after 30 d in 75 % E/W this increased from 1.9 % to 2.9 %. Depending on the material and storage condition, the percentage creep strain recovery after 30 d ranged between 65.2 % and 80 %. Increased filler loading in the bulk-fill RBCs decreased the creep strain magnitude and increased the surface hardness. SignificanceSolvent storage decreased the Martens hardness of both upper and lower surfaces and increased the bulk creep characteristics of bulk-fill RBCs. Nevertheless, there was a similar relative stability in surface hardness and viscoelastic stability of fast-cured PowerFill compared to conventionally irradiated RBCs.

Influence of Direct Coronal Restoration Materials on the Fracture Resistance of Endodontically Treated Premolars: An In Vitro Study.

(1) Background: The long-term survival of an endodontically treated tooth depends on a successful root canal treatment as well as an adequate definitive coronal restoration. This study aimed to evaluate the strength of endodontically treated premolars with mesial-occlusal-distal (MOD) cavity preparation restored with different direct coronal restoration materials but from the same manufacturer against fracture. (2) Methods: sixty intact premolars were selected and placed into five groups (n = 12): G1-intact teeth, G2-endodontic treatment and unrestored MOD cavities, G3-endodontic treatment and MOD cavities restored with Tetric PowerFlow and Tetric EvoCeram, G4-endodontic treatment and MOD cavities restored with Multicore Flow and Tetric EvoCeram, and G5-endodontic treatment and MOD cavities restored with Multicore Flow. The specimens were subjected to an axial compression load at a speed of 1.6 mm/min and optically inspected before and after with a stereomicroscope. For each premolars group, the following data were recorded: the compression resistance, the compressive strength, and the maximum force supported. The microstructure of the samples after the compression test was analyzed using scanning electron microscopy (SEM). (3) Results: statistical analysis (ANOVA and Tukey test) showed that there was a statistically significant difference between G1 and the other groups. Even though there was no statistically significant difference between the restored groups, a better mechanical behavior was registered within the G3. (4) Conclusions: this in vitro study indicated that none of the materials used can lead to a higher or at least similar fracture resistance as the intact teeth. The coronal restoration only with nano-hybrid composites may lead to a higher therapeutic benefit for the fracture-susceptible premolars.

Diversity of short-term DC outcomes in bulk-fill RBCs subjected to a 3 s high-irradiance protocol

ObjectivesTo determine the short-term (5 min) initial effects of a high-irradiance light-curing (LC) protocol on light transmission (LT%), radiant exposure (RE) and degree of conversion (DC%) of different bulk-fill resin-based composites (RBCs). Materials and methodsSix bulk-fill composites with different viscosities were investigated: OBF (One Bulk Fill, 3 M), EB (Estelite bulkfill,Tokuyama), PFill, PFlow, ECeram and EFlow (PowerFill, Poweflow, Tetric EvoCeram bulkfill, Tetric Evoflow bulkfill, Ivoclar), subjected to different LC protocols: one ultra-high-intensity (3 W/cm2 −3 s via PowerCure LCU) and two conventional (1.2 W/cm2 −10 s and 20 s via PowerCure and Elipar S10 LCUs). Specimens (n = 5) were polymerized within their molds (ϕ5 mm × 4 mm depth) to determine LT% and RE at 4 mm using a MARC-LC spectrometer. For real-time DC% measurements by FTIR, similar molds were utilized. Data were analyzed by one-way ANOVA and Tukey post-hoc tests at 5 % significance. ResultsRegardless of the applied LC protocols, OBF and low-viscosity RBCs (EB, PFlow and EFlow) had the lowest and highest LT%, RE, DC% and RPmax, respectively. RE results of all RBCs were in the same sequence: Elipar-20 s > PCure-10 s > PCure-3 s. DC% of PFill and PFlow displayed no significant difference between the applied LC protocols (p > 0.05). The polymerization kinetic in all materials was well described by an exponential sum function (r2 varied between 0.85 and 0.98), showing a faster polymerization with the PCure-3 s protocol. SignificanceThe measurement of LT% and DC% at 5 min gave an insight into the developing polymerization process. The initial response of these bulk-fill composite to a high-irradiation protocol varied depending on their composition and viscosity, being faster for low viscosity materials. Nevertheless, even though multiple resin composites are designed to be efficient during photopolymerization, care should be taken when selecting materials/curing protocol.

The Influence of Ionizing Radiation on the Morphological Structure of the Fluoride-Releasing Restorative Materials in Cancer Patients: An In Vitro Study

Radiotherapy plays a key role in the treatment of the early and advanced stages of head and neck cancer. To date, there is still no consensus on the effects of radiotherapy on the mechanical properties of fluoride-releasing restorative materials which can be used in patients undergoing radiotherapy with increased incidence of caries. The fluoride-releasing materials Equia Forte HT and Cention N were compared to the resin-based materials Tetric EvoCeram and Tetric Power Fill. Standard irradiation was performed with a linear accelerator. Vickers microhardness, mass, surface roughness and color were measured before and after irradiation. Cention N and Tetric PowerFill showed stability in the mass, while the surface roughness did not change in any of the examined groups. Resistance to microhardness change was shown by Cention N, Tetric PowerFill and Tetric EvoCeram, and the color change was significant in all groups (p < 0.05). It should be remembered that patients receiving head and neck radiation therapy may experience adverse effects from the treatment, including changes in the mechanical properties of the restorative materials. The obtained results suggest that Cention N can be used as a material in patients undergoing head and neck radiotherapy due to the mechanical stability and depo effect of fluoride release.

Esthetic comparison of two composites used for Invisalign's attachments bonding.

Esthetics is a factor of great importance for most patients undergoing treatment with Invisalign® aligners. When choosing a resin composite for the bonding of attachments required for the treatment, ideal characteristics such as low visibility and stain resistance of the material are essential to increase the overall perceived esthetics of the treatment. The objective of this article was to evaluate the esthetics of two resin composites used for attachment reproduction: the Transbond XT® from 3M® and the Tetric EvoCeram® from Ivoclar Vivadent®. An analytic, observational, longitudinal, and prospective study was done. Attachments were bonded on 51 patients, and a dental survey about esthetics was given 3 months after the bonding of attachments. The Student's t-test and 1-factor ANOVA tests were used, when the variables were normal, and the nonparametric alternative of the tests was used when they were not distributed normally. The results indicate that there are no statistically significant differences (p>.05) in the esthetic perception of attachments according to the type of composite used. Even if some differences are observed between the resins, both Transbond XT® and Tetric EvoCeram® can be considered for attachments bonding from an esthetical point of view. Key words:Clear aligner therapy/Dental bonding/Orthodontic appliance/Dental Esthetics.

The color-matching ability of single-shade universal composites in extracted human teeth.

To evaluate the color-match with extracted natural teeth of three single-shade universal composites, a group-shade universal composite, and a highly translucent-shade conventional composite. Twenty extracted human teeth were divided into light- and dark-shade groups (n = 10, LSG and DSG). A preparation was restored with the 3 single-shade universal composites, OMNICHROMA (OMC), Admira Fusion x-tra U (AFU), and Essentia U (ESU); a highly translucent-shade conventional composite, Tetric EvoCeram T (TEC-T); and two shades of a group-shade universal composite-Filtek Universal Restorative (FUR A1 and A4). Composites were photopolymerized, polished, and stored in water for 24 h. The ΔE00 value between the unprepared and restored surfaces was obtained using a spectrophotometer. Composite placement and measurements were repeated three times per tooth. Color differences were statistically analyzed with the within-between-subjects t-test and repeated-measures analysis of variance (ANOVA), followed by post hoc pairwise comparisons with a Bonferroni adjustment (α = 0.05). There were no statistically significant differences between OMC and FUR (A1 and A4). AFU and ESU showed significantly higher ΔE00 values than OMC and TEC-T (p < 0.05). Single-shade composites exhibited significantly higher ΔE00 values in the DSG than in the LSG except ESU (p < 0.05). None of the composites satisfied the criteria for an acceptable match (ΔE00 >1.8). OMC showed the same color matching ability as a group-shade universal composite. A highly translucent-shade conventional composite and OMC exhibited better color matching ability than other single-shade composites. Overall, single-shade universal composites performed better in lighter-shaded teeth. Single-shade universal composites have the potential to reduce chair time by eliminating shade selection in cavities with lighter-shade teeth. Highly translucent incisal conventional composites also may be used if the appropriate shade of composite is not available.

Monomer elution and shrinkage stress analysis of addition-fragmentation chain-transfer-modified resin composites in relation to the curing protocol

ObjectiveThe purpose was to compare the effects of rapid (3 s) and conventional (20 s) polymerization protocols (PP) of mono- and multichip LED curing units (LCU) on shrinkage stress (SS) and monomer elution (ME) in bulk-fill resin-based composites (RBC) with and without addition-fragmentation chain-transfer (AFCT) monomer. MethodsCylindrical (5x4mm) specimens were prepared from two RBCs containing different AFCT monomers (Filtek OneBulk-FOB; Tetric PowerFill-TPF) and one without (Tetric EvoCeram Bulk-TEC). After soaking for 3, 10, and 14 days (75 % ethanol), ME was quantified using standard monomers by High-Performance Liquid Chromatography. SS was measured from the start of polymerization to 5 min using a Materials Testing Machine. The radiant exitance of LCUs was measured using a spectrophotometer. ANOVA and Tukey's post-hoc test, multivariate analysis and partial eta-squared statistics were used to analyze the data (p < 0.05). ResultsAFCT-modification significantly decreased ME (p < 0.001). ME was reduced by half by day 10 and by one tenth by the end of the 14-day compared to the 3-day sampling. ME itself was dependent, whereas the percentage of monomers released was independent of the PP used (p > 0.05). FOB showed the lowest SS (p < 0.001), while there was no significant difference between TPF and TEC (p = 0.124). Both ME and SS were significantly influenced by material type and PP. SignificanceThe incorporation of the AFCT monomer reduced ME, but this was inversely related to a decrease in exposure time. SS values reduced by rapid PP in parallel with increasing ME values. The utilization of the AFCT molecule in conjunction with an appropriate resin-, initiator-system is of significant consequence for the kinetics of polymerization and the incorporation of monomers into the network.

Evaluation of the microleakage of new bioactive restorative materials: a comparative in-vitro study.

This in-vitro study aimes to compare the microleakage of different restorative materials namely EQUIA Forte (GC, Japan), Tetric Evoceram (Ivoclar Vivadent, Liechtenstein), and Activa BioACTIVE. A standardized class V cavity has been created on the buccal surface of 40 sound premolar teeth. The cavity had the following measurements: 3 mm buccolingual height, 2 mm axial depth, and 4 mm mesiodistal width. The gingival margin was 1mm below the cementoenamel junction, whereas the coronal margin was on the enamel with cavosurface margins were butt joints all around. Four groups of teeth were restored according to the restorative materials. Under a stereomicroscope, the dye penetration test was used to measure the microleakage after thermocycling of the teeth. Data were compared using Kruskal-Wallis H and Mann-Whitney U tests. Occlusal and gingival margins did not show statistically significant differences among the four groups, but an intragroup analysis revealed a significant difference. The type of restorative material did not appear to have a substantial impact on microleakage, according to the findings of the current investigation.

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.

Dental restorative materials and halitosis: a preliminary in-vitro study

Despite the widespread use of dental restorative materials, little information exists in the literature regarding their potential impact on bad breath. This in vitro study aims to fill this gap by investigating the influence of different restorative materials on the release of hydrogen sulfide (H2S). Thirteen diverse dental restorative materials, including composites, flowable composites, glass ionomer restorative materials, high-copper amalgam, and CAD–CAM blocks, were examined. Cellulose Sponge models were used as negative and positive control. All samples were prepared with a diameter of 5 mm and a height of 2 mm. Except for the negative control group, all samples were embedded into Allium cepa L., and the emitted H2S was measured using the Wintact W8802 hydrogen sulfide monitor. Surface roughness’s effect on emission was explored by roughening the surfaces of CAD–CAM material samples, and gas emission was measured again. The data were statistically analyzed using the Kruskal–Wallis test and DSCF pairwise comparison tests. Fiber-reinforced flowable composite (EverX Flow), amalgam (Nova 70-caps), and certain composite materials (IPS Empress Direct, Tetric Evoceram, Admira Fusion X-tra) released higher H2S concentrations compared to the negative control. The H2S release period lasted longer in the same materials mentioned above, along with G-aenial Universal Injectable. Indirectly used materials, such as GC Cerasmart, Vita Enamic, and Vita YZ HT, demonstrated significantly lower emissions compared to other direct restoratives. Importantly, the surface roughness of indirect materials did not significantly affect peak H2S concentrations or release times. The study reveals variations in H2S release among restorative materials, suggesting potential advantages of indirect restorative materials in reducing H2S-induced halitosis. This comprehensive understanding of the relationship between restorative materials and halitosis can empower both dental professionals and patients to make well-informed treatment choices. Notably, there is evidence supporting the enhanced performance of indirect restorative materials for individuals affected by halitosis.

Effect of polymerisation protocols on water sorption, solubility and hygroscopic expansion of fast-cure bulk-fill composite

ObjectiveThis study examines the effect of two light-curing protocols from a LED polywave light curing unit (LCU) on water sorption, solubility, and hygroscopic expansion of fast and conventional bulk-fill resin-based composites (RBCs) aged in distilled water for 120 d. MethodsThree bulk-fill RBCs materials were studied: Tetric PowerFill® (fast photo-polymerised composite) (TPF), Tetric EvoCeram bulk-fill (EVO), and GrandioSo x-tra bulk-fill (GSO) (conventional photo-polymerised composites). Specimens were prepared within a 3D-printed resin mold (8-mm diameter x 4-mm height) and light-cured from one side only with 2 modes of polywave LCU (Bluephase® PowerCure): 3 s mode and for 20 s in “Standard” mode. Water sorption and solubility were measured at fixed time intervals for 120 d of distilled water storage, then reconditioned to dry to measure desorption for 75 d, all at 37 ± 1 °C. Hygroscopic (volumetric) expansion was recorded at the same time intervals up to 120 d. Data were analysed through SPSS using Two-way ANOVA, One-way ANOVA, independent t-tests, and Tukey’s post-hoc correction tests (p < 0.05). ResultsTPF, when irradiated for 3 s demonstrated minimal water sorption (0.83%), solubility (1.01 μg/mm3), and least volumetric expansion (1.64%) compared to EVO and GSO. While EVO showed the highest water sorption (1.03%) and solubility (1.95 μg/mm3) at 3 s. GSO had the lowest sorption (0.67%) and (0.56%) in 3 s and 20 s protocols, respectively. Nevertheless, all the sorption and solubility data were within the ISO 4049 limits. SignificanceFor TPF, fast (3 s) polymerisation did not increase either water sorption or solubility, compared with 20 s irradiation. However, with the two comparative bulk-fill composites, fast cure increased water sorption by 15–25% and more than doubled solubility. These findings were consistent with the lesser volumetric expansions observed for Tetric PowerFill at both the fast and standard protocols, indicating its relative stability across polymerisation protocols.

Mechanical Properties of Direct Composite Resins and CAD/CAM Composite Blocks

The widespread application of CAD/CAM technology in contemporary dentistry led to the development of promising restorative materials, such as resin composite blocks (RCBs). Thus, the present study aims to evaluate the mechanical properties of RCBs, comparing this material to the direct composite resin from the same manufacturer. Samples retrieved from three CAD/CAM resin composite blocks (Tetric CAD (TC), Ivoclar Vivadent, Grandio blocs (GB), VOCO GmbH and Brilliant Crios (BC), Coltene/Whaledent) and four direct composite resins (Tetric EvoCeram (TEC), Ivoclar Vivadent, GrandioSO (GS), VOCO GmbH, Brilliant EverGlow Translucent (BET) and Universal Shade (BEU), Coltene/Whaledent) were submitted to three-point bending flexural test and Vickers microhardness test. The resulting data of the flexural strength were analyzed using one-way ANOVA considering Bonferroni correction for post hoc tests (α = 0.05). The flexural modulus and Vickers microhardness results were analyzed using Welch’s ANOVA considering Games–Howell correction for post hoc tests (α = 0.05). Regarding results, flexural strength and flexural modulus values ranged from 81.1 MPa (BEU) to 246.5 MPa (GB) and 10.6 GPa (BEU) to 20.3 GPa (GB), respectively. GS (121.2) and GB (136.2) groups were associated with the highest microhardness values. According to the post hoc tests, statistically significant differences in flexure strength were found in RCBs (BC, GB, and TC) compared to all direct composite resins. Flexural modulus and Vickers microhardness of RCBs (BC, GB, TC) were also significantly different from the direct composite resin (BET, BED, and TEC), except when comparing GS and GB for microhardness. In conclusion, differences between RCBs and direct composite resins were observed regarding flexural strength, flexural modulus, and microhardness, revealing that RCBs have enhanced mechanical properties compared to direct composite resins.

Effect of high irradiance and short exposure times on the depth of cure of six bulk-fill resin composites.

This study examined the effect of high irradiance and short exposure times on the depth of cure of six resin-based composites (RBCs). Bluephase PowerCure and the Valo X light-curing units (LCUs) were used to photocure bulk-fill RBCs for their recommended exposure times: Admira Fusion x-tra (AFX/20s), Aura Bulk Fill (ABF/20s), Filtek One Bulk Fill (FOB/20s), Opus Bulk Fill APS (OBF/30s), Tetric EvoCeram Bulk Fill (TEC/10s) and Tetric PowerFill (TPF/10s). In addition, all bulk-fill RBCs were tested for depth of cure with one short 3 s exposure time from the Bluephase PowerCure or the Valo X in the Xtra Power mode. The RBCs (n=10 per RBC) were inserted into a 4mm diameter metal mold and covered by a polyester strip before being photocured. After 24h of storage, uncured RBC was scraped away to determine the depth of cure of the RBCs. None of the RBCs achieved a 4mm depth of cure. The depth of cure of TEC and TPF was unaffected by the exposure times (recommended or short) when using the Valo X. The depth of cure of AFX/20s, AFX/Xtra Power, ABF/Xtra Power, FOB/Xtra Power, and OBF/30s RBCs was greater when using Valo X compared to the Bluephase PowerCure. It was concluded that short exposure times can reduce depth of cure and should only be used for some RBCs.

Comparison of Blue and Infrared Light Transmission Through Dental Tissues and Restorative Materials.

The depth of cure using blue-light photocuring units (BL) is limited by tooth structure and qualities of the restorative material through which the activating wavelength must pass. Recent developments incorporate an infrared (IR) activated upconversion (UC) fluorescence of a lining agent filled with nanocrystals of NaYF4 and doped with YB+3 and Tm+3 that emit both blue and violet light locally at the interface of the liner and restorative resin. The purpose of this study was to evaluate the BL and 975 nm infrared (IR) light power transmission through dental tissues and restorative materials. Power transmissions of the IR laser (975 nm) and a monowave blue-only light-curing unit (Bluephase 16i) through dental tissues (enamel, dentin, and enamel/dentin junction, or DEJ), eight (8) various dental resin composites, and eight (8) dental ceramics, each at four thicknesses (1, 2, 3 and 4 mm) were evaluated (n=5) using a thermopile sensor (PM10, Coherent Inc) connected to a laser power meter (Fieldmate, Coherent Inc). Power transmission values of each light source and restorative material were subjected to analysis of variance and Tukey test at a pre-set alpha of 0.05. A linear correlation (r=0.9884) between the supplied current and emitted IR power of the laser diode was found, showing no statistical power reduction with increased distances (collimated beam). For tooth tissues, the highest power transmissions for both light sources were observed using 1.0 mm enamel while the lowest values were found for 2.0 mm dentin and an association of 2.0 mm DEJ and 1.0 mm dentin. The only group where IR demonstrated significantly higher transmission when compared to BL was 1.0 mm enamel. For all resin composites and dental ceramics, increased thickness resulted in a reduction of IR power transmission (except for EverX Posterior fiber-reinforced composite and e.max HT ceramic). IR resulted in higher transmission through all resin composites, except for Tetric EvoCeram White. The highest BL transmission was observed for SDR Flow, at all thicknesses. Higher IR/BL ratios were observed for EverX Posterior, Herculite Ultra, and Lava Ultimate, while the lowest ratio was observed for Tetric EvoCeram White. Reduced translucency shades within the same material resulted in lower power ratio values, especially for BL transmission. Higher IR/BL ratios were observed for e.Max LT, VitaVM7 Base Dentin, and e.max CAD HT, while the lowest values were found for VitaVM7 Enamel and Paradigm C. IR power transmission through enamel was higher when compared to blue light, while no difference was observed for dentin. The power transmission of IR was higher than BL for resin composites, except for a high value and low chroma shade. Fiber-reinforced resin composite demonstrated the highest IR/BL power transmission ratio. A greater IR/BL ratio was observed for lower translucency ceramics when compared to high translucency.

Effect of Preheating on Microhardness, Degree of Conversion, and Depth of Cure of Various Bulk-Fill Composites

Background: This study aims to evaluate the effect of preheating on microhardness, degree of conversion, and depth of cure of bulk-fill composites (Tetric EvoCeram Bulk-Fill, SonicFill2) and a conventional composite (Tetric EvoCeram). Methods: Layers of Tetric EvoCeram (2 mm), Tetric EvoCeram Bulk-Fill (4 mm), and SonicFill2 (5 mm) were placed in 4-mm diameter molds and polymerized at room temperature or heated to 55oC for 10 s with a total number of 60 samples. Then, the top surfaces of samples were polished. 30 samples’ Vickers microhardness was measured from the top and bottom surfaces. The other 30 samples were pulverized into a fine powder, and the composites’ degree of conversion was measured with attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Obtained data were analyzed statistically with a significance level of p&amp;lt;0.05. Results: The degree of conversion of Tetric EvoCeram was higher than the minimum rate of clinically acceptable value, which is 55%, but the scores of Tetric EvoCeram Bulk-Fill and SonicFill2 were below the threshold. Preheating increased the degree of conversion of Tetric EvoCeram Bulk-Fill and SonicFill2. In addition, preheating did not affect depth of cure of SonicFill2 but decreased the rate of Tetric EvoCeram Bulk-Fill. Conclusion: The results showed that the effect of preheating on the degree of conversion and depth of cure varied according to the material. Keywords: Preheating, bulk-fill composite, degree of conversion, depth of cure, microhardness.

Microscopic Comparison of the effect of Three Polishing Systems on a Nanofiller Composite Resin

In restorative dentistry, selection of materials is decisive to obtain optimal aesthetic results, in the case of dental resins, the size characteristics and particle distribution of the different polishing systems, constitute a factor considerably influences the results. Objective: The purpose of the present research work was to compare three systems employed to polishing composite resin, documenting the results at the microscopic level, to identifying which of them showed better results concerning the roughness. Material and methods: Three polishing systems were evaluated: Soflex from 3M®, Optra Pol and Astrobrush from Ivoclar® Vivadent and Jiffy Hishine from Ultradent, employing the LSM 700 Confocal Microscopy System, also roughness was observed and registered on the surface of a nanofiller resin Tetric Evoceram Ivoclar® Vivadent inserted in stainless steel molds. Results: The roughness mean observed were as follows: 13.95μm for Soflex of 3M®, 13.45μm for Optra Pol of Ivoclar® and 8.05μm for Jiffy Hishine Ultradent. All data recorded in Microsoft Excel 2010 IBM STATISTICS, determinated statistical differences between the groups of Ultradent®. Conclusion: The lowest roughness corresponded to Ultradent with values of 8.01μm.

Effect of artificial aging on the stability of color match of Omnichroma composite resin

Purpose To evaluate the effect of artificial aging on the stability of color match between the teeth and Omnichroma composite resin compared to that in the teeth restored with Tetric EvoCeram nanohybrid composite resin. Materials and methods Twenty sound, freshly extracted human maxillary premolars were mounted in acrylic blocks. The baseline shade of the selected teeth was A2 as measured from the middle third of the buccal surface by spectrophotometer (Vita Easyshade Advance). Trapezoidal Class V cavity was prepared on the buccal surface of each tooth 0.5 mm coronal to CEJ. Cavity dimensions were width of 4 mm occlusally and 3 mm gingivally, 2 mm occluso-gingival length and 1.5 mm depth. A 45-degree bevel was placed on the occlusal cavity margin. Results Specimens were randomly divided into two equal groups (n = 10) representing the materials used to restore the cavities. Group I: Tetric EvoCeram while Group II: Omnichroma. Specimens were artificially aged by storage for 6 months in artificial neutral saliva in an incubator at 37 ± 5°C during which the saliva was replaced daily. Color measurements and ΔE values were recorded before cavity preparation representing the baseline tooth color to be used for detection of the initial color match between the tooth and restoration where their color was measured after storage in saline for 24 h. Conclusion At the end of the storage period, the color of both the teeth and the restorations was remeasured to detect the stability of color match between the restoration and the tooth due to storage.

Influence of Layer Thickness and Shade on the Transmission of Light through Contemporary Resin Composites.

Material-dependent parameters have an important impact on the efficiency of light polymerization. The present in vitro study aimed to investigate the influence of the increment thickness and shade of nano- and nanohybrid resin composites on the transmission of curing light. Three contemporary resin composites were evaluated: Tetric EvoCeram® (TEC); Venus Diamond® (VD); and Filtek Supreme XTE® (FS XTE). Light transmission (LT) was recorded in accordance with the sample thickness (0.5 to 2.7 mm) and the shade. Polymerized samples were irradiated for 10 s each using the high-power LED curing light Celalux 2 (1900 mW/cm2). LT was simultaneously recorded using the MARC Patient Simulator (MARC-PS). LT was strongly influenced by the composite layer thickness. For 0.5 mm-thick samples, a mean power density of 735 mW/cm2 was recorded at the bottom side. For the 2.7 mm samples, a mean power density of 107 mW/cm2 was measured. Only LT was markedly reduced in the case of darker shades. From A1 to A4, LT decreased by 39.3% for FS XTE and 50.8% for TEC. Dentin shades of FS XTE and TEC (A2, A4) showed the lowest LT. The thickness and shade of resin composite increments strongly influences the transmission of curing light. More precise information about these parameters should be included in the manufacture manual.

Clinical performance of a glass-hybrid system in comparison with a resin composite in two-surface class II restorations: a 5-year randomised multi-centre study

ObjectiveTo evaluate the 5-year clinical performance of a glass hybrid restorative system and a nano-hybrid resin composite in moderate to large two-surface class II cavities.Materials and methodsThis study was carried out by dental schools in Zagreb, Croatia; Izmir, Turkey; Belgrade, Serbia; and Milan, Italy. A total of 180 patients requiring two class-II two-surface restorations in the molars of the same jaw were recruited. The teeth were randomly restored with either a nano-hybrid resin composite (Tetric EvoCeram, Ivoclar Vivadent) or a glass-hybrid material (EQUIA Forte, GC). During the 5-year follow-up, two calibrated evaluators at each centre scored the restorations annually using the FDI-2 scoring system. The survival rates were calculated using the Kaplan–Meier method and compared using non-parametric matched pair tests (p < 0.05).ResultsThere were no statistically significant differences between the overall survival and success rates of the two types of restorations (p>0.05). The success rates (FDI-2 scores 1–3) for EQUIA Forte were 81.9% (average annual failure rate: 3.9%) and 90.7% for Tetric EvoCeram (average annual failure rate: 1.9%). The survival rates (FDI-2 scores 1–4) for EQUIA Forte and Tetric EvoCeram were 94.5% and 94.4%, respectively, with an average annual failure rate of 1.1%.ConclusionsIn terms of success and survival rates, both the glass-hybrid restorative system and the nano-hybrid resin composite have been shown to perform satisfactorily.Clinical relevanceThe results of this study indicate that EQUIA Forte can be one of the therapeutic options for moderate to large two-surface class II restorations of posterior teeth.