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Objective: To analyse the bond quality in dentine post-ageing after salivary contamination and decontamination at different stages of dental adhesive application., Materials and Methods: A total of 1120 human dentine specimens were randomly allocated to 14 groups for four intervals (n = 20) to be treated with a self-etching (SE) and universal (U) adhesive. The saliva contamination and decontamination were implemented after surface preparation, after primer application (for SE) and after adhesive curing. The decontamination groups were either rinsed and air-dried or rinsed, air-dried and reapplied with adhesive. They were stored (37 °C, distilled water) for four intervals (1 week, 1 month, 3 months and 1 year) and subjected to shear bond strength (SBS) test at a crosshead speed of 0.5 mm/min., Result: One-way ANOVA with Tukey's test (α = 0.05) revealed significant reduction in SBS in all the groups in U adhesive compared with the control group at 1 week (p < 0.0001) and in SE when the contamination took place after primer application. However, decontamination improved the SBS in SE but not in U adhesive. The univariate analysis confirmed significant influences (p < 0.0001) seen by treatment procedure ([Formula: see text]=0.075), type of adhesive ([Formula: see text] = 0.328), ageing ([Formula: see text] = 0.13), experimental groups ([Formula: see text] = 0.518), and the stage of influence ([Formula: see text] = 0.60)., Conclusion: Saliva contamination is detrimental after primer application in SE but, decontamination regained the SBS and maintained it over time. In U adhesive, SBS deteriorated over time irrespective of the contamination., Clinical Relevance: Salivary contamination showed different influences on SBS at various stages of restoration with contemporary dental adhesives.

Objectives: The study aims analyzing if improved opacity in modern high-viscosity bulk-fill resin composites (BF-RBC) contradicts with the sufficiency of curing and to assess material's tolerance to less ideal curing conditions., Materials and Methods: Simulated large cavities (10 × 6) mm were filled in one increment with three BF-RBCs (Filtek One, FO; Tetric Evo Ceram Bulk Fill, TEC-BF; SonicFill2, SF2). One central and two peripheral (4 mm apart from the center) micromechanical property line-profiles (HV, Vickers hardness; Y HU , indentation modulus) were measured in 0.2-mm steps at 24 h post-polymerization (n = 6). Depth of cure (DOC) was calculated from the HV variation in depth. A scratch test (DOC scratch test ) estimated the tolerance in polymerization when simulating clinically relevant curing conditions (exposure distance up to 7 mm; centered and with a 3-mm offset placement of the LCU). Irradiance and spectral distribution of the used light curing unit (LCU) were assessed at various curing conditions., Results: DOC varied among 3.6 mm (SF2, peripheral) and 5.7 mm (FO, central). The BF-RBC influences DOC stronger (p < 0.001, ηP 2  = 0.616) than the width (p < 0.001, ηP 2  = 0.398). Significant lower DOC (t test) was measured peripheral compared to center in all materials. Y HU was more sensitive to the varied parameters as HV. DOC scratch test varied among 2.4 mm (SF2, 3-mm offset, exposure distance 7 mm) and 3.9 mm (FO, center, 0 mm)., Conclusions: Whether opacity competes with DOC is material dependent. BF-RBCs tolerate small variations in LCU's centricity better than variations in exposure distance., Clinical Relevance: The upper incremental thickness threshold of 4 or 5 mm was not reached in all BF-RBCs under simulated clinically relevant curing conditions.

Purpose: To investigate dentin bond strength of experimental composites based on a bis-GMA/TEG-DMA composite filled with a varying amount (0 to 40 wt%) of bioactive glass 45S5 (BG) at a total filler content of 70 wt%., Materials and Methods: Specimens for shear bond strength testing (diameter = 3.12 mm, height = 3 mm) were bonded to human dentin using a two-step self-etch adhesive and subjected to aging in water at 37°C for 1 week, 1 month, 3 months, 6 months, and 1 year. A total of 600 specimens were prepared (6 materials × 5 aging times × 20 specimens per experimental group). Bond strength was tested by loading specimens in a universal testing machine at a constant crosshead speed of 0.5 mm/min until fracture. Reliability analysis was performed using Weibull statistics., Results: Experimental composites with a low BG content (up to 5 wt%) showed dentin bond strength and reliability comparable to those of the commercial reference composite. A further increase in the BG amount diminished both bond strength and reliability. The bond strength decline was linearly dependent on the amount of BG when observed within each aging time. One-year aging in water caused no deterioration of bond strength, but diminished bond reliability. The reliability after 1-year aging was similar among all composites, including the commercial reference composite., Conclusion: The variation in BG amount diminished the bond strength and reliability in a dose-dependent manner.

Purpose: To review and critically analyze the literature concerning the influence of salivary contamination on the bond quality of adhesives used in restorative materials by comparing and contrasting the different adhesive materials., Methods: A detailed search on PUBMED, Cochrane Library, Google Scholar and Web of Science was carried out to identify publications on salivary contamination and dental adhesive materials, from 1990-2017 (March) which resulted in a total of 6,202 web-identified publications. After screening titles/abstracts and de-duplicating, 54 publications were selected that matched the requirements for this review. The condition for selection was English literature concerning the effect of salivary contamination on the adhesives used in restorative dentistry. The obtained articles were systematically evaluated., Results: Salivary contamination of adhesives during restorative procedures statistically (64.6%) showed an adverse effect on adhesives, occurring either at one or many stages of restoration. Methodological dissimilarities impeded the direct comparison of the selected studies. Nevertheless, the 2-step etch and rinse adhesives were relatively less vulnerable to salivary contamination than the others. 65% of the evaluated studies for decontamination achieved improved bonding when the contaminated surface was subjected to some kind of decontamination procedure. However, the duration and other specificities were not standard in all the evaluations and need further research to assess the course of action. It is necessary to do long term studies to evaluate the effectiveness of contaminated adhesive over time., Clinical Significance: Salivary contamination is a potential cause for poor bond quality of adhesive systems during restorative procedures and to provide a successful treatment, proper care must be taken to ensure the operating area is free from contamination. Understanding the properties of the materials and its constituents as well as considering measures to manage the potential vulnerabilities due to salivary contamination in the area of bonding might help a clinician to produce better results., Competing Interests: The authors declared no conflict of interest.

Objectives: The study aims to characterise the curing behaviour of a light-curing luting composite (Variolink® Aesthetic LC, Ivoclar Vivadent) polymerised at different exposure times (10 s, 20 s) through different ceramics (IPS Empress CAD and IPS e.max CAD, Ivoclar Vivadent) and ceramic thicknesses (no ceramic, 0.5, 1, 1.5 and 2 mm)., Material and Method: Curing units' (Bluephase Style, Ivoclar Vivadent) variation in irradiance delivered up to 10-mm exposure distance as well as the incident and transmitted irradiance and radiant exposure up to 6-mm ceramic thickness were assessed on a laboratory-grade spectrometer. A total of 216 (18 groups, n = 12) thin and flat luting composite specimens of 500-μm thickness were prepared and stored after curing in a saturated vapour atmosphere for 24 h at 37 °C. Micro-mechanical properties (Vickers hardness, HV and indentation modulus, Y HU ) were determined by means of an automatic micro-hardness indenter., Results: Within the study design, the radiant exposure received by the luting composite varied from 2.56 to 24.75 J/cm 2 , showing a high impact on the measured properties. Comparing the effect of the parameters exposure time, ceramic thickness and type, the highest influence on the micro-mechanical parameters was identified for exposure time, while this influence was stronger on HV (p < 0.001, η P 2  = 0.452) than on Y HU (p < 0.001, η P 2  = 0.178). The influence of ceramic type was significant but low (η P 2  = 0.161 on HV and 0.113 on Y HU ), while the influence of ceramic thickness was the lowest (η P 2  = 0.04 and 0.05, respectively)., Conclusions: Slightly higher irradiance values were transmitted through Empress CAD up to a ceramic thickness of 3 mm (p < 0.001), while being comparable with e.max for thicker slices. Differences in translucency between ceramics were reflected in the micro-mechanical properties of the luting composite., Clinical Relevance: The radiant exposure reaching the luting composite is determined by the incident irradiance, exposure time, ceramic type and ceramic thickness. At the analysed incident irradiance, exposure time was the most consistent parameter affecting the micro-mechanical properties of the luting composite, and this effect was strongly reflected in the more translucent ceramic Empress CAD. Within the curing conditions, an exposure time of 20 s is recommended.

Purpose: This study investigated the influence of several methodological details on the shear bond strength (SBS) testing of pit and fissure sealants. The following variables were considered: type of enamel surfaces, prismatic vs aprismatic enamel, etching time, and aging and shearing procedures., Materials and Methods: The surfaces of 180 healthy human third molars were divided into 4 different sections (mesial, distal, buccal, and oral). After tooth separation, the specimens were randomly allocated to the following groups: 1) enamel preparation: prismatic vs aprismatic; 2) etching: 30 s vs 60 s; 3) aging: 1 day or 3 months vs 5000 thermocycles; 4) shearing: notched-edge method (ISO 29022:2013) vs knife-edge method. After following each protocol, SBS was determined using a universal testing machine, followed by failure mode analysis. Data were analysed using Mann-Whitney U-tests and regression analyses., Results: In the aprismatic enamel group, the longer etching time resulted in slightly, not statistically significantly higher SBS. When aging sealants on aprismatic enamel with different procedures, significantly lower SBS was found for 5000 thermocycles. In the case of aprismatic enamel etched for 60 s and sheared with the notched-edge blade, there was no significant difference between the aging procedures. Failure mode analysis showed adhesive failures to be predominant. Simple linear regression revealed that all of the included factors significantly influenced SBS. In a multiple linear regression model, the variables "aprismatic enamel" and "distal surface" were associated with a higher SBS; "5000 thermocycles" reduced SBS significantly., Conclusion: Enamel grinding, aging method, and type of enamel surface significantly influenced the SBS.

Objective: Since bulk-fill (BF) resin composites should cure efficiently to a depth up to 4mm, the aim of the study was to determine the time-dependence of degree of conversion (DC) at that depth during 24h post-irradiation., Methods: Eight representative BF resin composites were studied [x-tra base (XTB), Venus Bulk Fill (VBF), Tetric EvoCeram Bulk Fill (TECBF), Sonic Fill (SF), Filtek Bulk Fill (FBF), everX Posterior (eXP), Beautifil-Bulk Flowable (BBF), Beautifil-Bulk Restorative (BBR)]. Specimens were fabricated in white Delrin moulds of 4mm height and 5mm internal diameter directly on an attenuated total reflectance (ATR) accessory attachment of an (FTIR) spectrometer (Nicolet iS50, Thermo Fisher, Madison, USA). Upper specimen surfaces were irradiated in situ for 20 s with an LED curing unit (Elipar S10 with average tip irradiance of 1200 mW/cm(2)). Spectra from the lower surface were recorded continuously in real-time for 5 min and then at 30 and 60 min and 24h post irradiation., Results: Mean ranges of DC4mm (%) of the materials at 4mm depth were 39-67; 48-75; 45-74; and 50-72 at 5, 30 and 60 min and 24h respectively. DCs for XTB, VBF, TECBF, FBF, BBR increased significantly 30 min after irradiation (p<0.05) and were not affected by subsequent time up to 24h (p>0.05). DC for SF was not affected by subsequent time after 5 min (p>0.05). For eXP and BBF, DC increased 24h after irradiation (p<0.05). The data were described by the superposition of two exponential functions characterising the gel phase (described by parameters a, b) and the glass phase (described by parameters c and d)., Significance: Post polymerization impact of bulk-fill composites is material dependent. Five materials exhibited their maximum DC4mm already 30 min after starting the irradiation while DC4mm for two materials optimized after 24h. BF materials were found to exhibit after 24h a DC between 50 and 72% at 4mm depth under the stated irradiation conditions., (Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Statement of Problem: Little information is available about the translucency of monolithic CAD/CAM materials., Purpose: The purpose of this study was to evaluate the translucency of restorative CAD/CAM materials and direct composite resins with respect to thickness and surface roughness., Materials and Methods: In total, 240 disk-shaped specimens (12×14×1 mm and 12×14×2 mm) of 3 different CAD/CAM glass ceramics (CELTRA Duo, IPS e.max CAD, IPS Empress CAD), a fine-structure feldspathic ceramic (VITA Mark II), a hybrid ceramic (VITA Enamic), a resin nanoceramic composite resin (LAVA Ultimate), an experimental (CAD/CAM nanohybrid composite resin), 2 interim materials (Telio CAD; VITA CAD-Temp), and 3 direct composite resins (Tetric EvoCeram; Filtek Supreme XTE; Tetric EvoCeram Bulk Fill) were fabricated (n=10). After 3 different surface pretreatments (polished, rough SiC P1200, or SiC P500), absolute translucency and surface roughness were measured using spectrophotometry and tactile profilometry. The influence of material type, thickness, and roughness on absolute translucency was analyzed using a multivariate analysis, 1-way ANOVA, and the Tukey HSD post hoc test (P<.05). Pearson correlations and statistical hypothesis tests were used to assess the results (P<.05)., Results: The effect of all tested parameters was significant among the materials (P<.05). The greatest influence on the measured translucency was thickness (partial eta squared ηP²=.988), closely followed by material (.982), and the pretreatment method (.835). The surface roughness was strongly influenced by the pretreatment method (.975) and type of material (.941)., Conclusion: Thickness and surface roughness are major factors affecting the absolute translucency of adhesively luted restorations., (Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objectives: This study aimed to assess the impact of curing conditions-exposure time, mode, energy density and exposure distance-on the efficiency of curing flowable bulk-fill resin-based composites (RBCs) at simulated clinical relevant filling depths., Materials and Methods: Four flowable bulk-fill RBCs were investigated by assessing in 200 μm steps the variation in micro-mechanical properties (Vickers hardness (HV) and indentation modulus (E)) within simulated 6-mm-deep fillings (n = 5), considering 16 different curing modes/conditions. The exposure duration was 5, 20 and 40 s in the standard power mode; 3, 4 and 8 s in the high power mode; and 3 and 6 s in the plasma mode. Besides, the curing unit was placed at 0 and 7 mm distance away from the specimen's surface. Measurements were performed after 24 h of storage in distilled water at 37 °C. The depth of cure (DOC) was calculated as the 80 % hardness drop-off. The curing unit's irradiance at exposure distances up to 10 mm was monitored for all irradiation modes in 1 mm steps by means of a laboratory-grade spectrometer., Results: Results were compared using one- and multiple way ANOVA and Tukey's honest significant difference (HSD) post hoc test (α = 0.05). A multivariate analysis (general linear model) assessed the effect strength of the parameters material, energy density reaching the specimen's surface (2.63 to 47.03 J/cm(2)), exposure distance and curing mode on HV, E and DOC. The effect of the parameter material was significant and strong on all measured properties (p < 0.05, partial eta-squared (η P (2)) = 0.683 for E, 0.724 for HV and 0.199 for DOC). Energy density exerted in all materials the strongest influence on the measured properties, while the influence of distance was strong on DOC and low or even not significant on HV and E., Conclusions: The susceptibility to variation in irradiance under the simulated clinical conditions was material dependent, while lower and upper energy density limits for curing the materials were defined., Clinical Relevance: Materials react differently to the supplied irradiance. An exposure time of 20 s at moderate irradiance is recommended for all materials. The highest mechanical properties were reached not at the specimens' surface, but in deeper layers (0.4 to 3.1 mm).

Statement of Problem: Dual-polymerized luting composite resin cements would benefit from enhanced irradiance transmitted through a ceramic restoration. A quantification of the amount of transmitted light through translucent zirconia is lacking., Purpose: The purpose of this study was to evaluate the amount of light (360 to 540 nm) passing through translucent and conventional zirconia and a glass ceramic with respect to material thickness and different polymerizing modes., Material and Methods: Six translucent and a conventional zirconia (negative control) and a glass ceramic (positive control) were considered. Ten specimens of each material and thickness (.5, 1, 1.5, 2, 2.5, 3 mm) were fabricated (n=480). Zirconia materials were sintered according to manufacturers' instructions. The irradiance passing the different ceramics and thicknesses was measured with a violet-blue LED polymerizing unit in 3 polymerizing modes (plasma, high, and standard power mode) with a USB4000 Spectrometer. The polymerizing unit was placed directly on the specimen's surface. Data were analyzed with one and multivariate analysis and the Pearson correlation analysis (α=.05)., Results: In all materials, the translucency and its rate decreased exponentially according to the specimen thickness. The highest influence on the measured irradiance passing through translucent zirconia was exerted by ceramic thickness (P<.05, partial eta squared [ηP²]=.998), closely followed by polymerizing mode (ηP²=.973), while the effect of the material (P=.03, ηP²=.06) and mean grain size (P=.029, ηP²=.027) was significant but low., Conclusions: Zirconia was less translucent than the glass ceramic, but the translucency decreased more slowly with material thickness, thus approaching the translucency of glass ceramics at a specimen thicknesses of 2.5 to 3 mm., (Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to quantify the blue light that passes through different incremental thicknesses of bulk fill in comparison to conventional resin-based composites (RBCs) and to relate it to the induced mechanical properties., Materials and Methods: Seven bulk fill, five nanohybrid and two flowable RBCs were analysed. Specimens (n = 5) of three incremental thicknesses (2, 4 and 6 mm) were cured from the top for 20 s, while at the bottom, a spectrometer monitored in real time the transmitted irradiance. Micro-mechanical properties (Vickers hardness, HV, and indentation modulus, E) were measured at the top and bottom after 24 h of storage in distilled water at 37 °C. Electron microscope images were taken for assessing the filler distribution and size., Results: Bulk fill RBCs (except SonicFill) were more translucent than conventional RBCs. Low-viscosity bulk fill materials showed the lowest mechanical properties. HV depends highly on the following parameters: material (ηp (2) = 0.952), incremental thickness (0.826), filler volume (0.747), filler weight (0.746) and transmitted irradiance (0.491). The bottom-to-top HV ratio (HVbt) was higher than 80 % in all materials in 2- and 4-mm increments (except for Premise), whereas in 6-mm increments, this is valid only in four bulk fill materials (Venus Bulk Fill, SDR, x-tra fil, Tetric EvoCeram Bulk Fill)., Conclusions: The depth of cure is dependent on the RBC's translucency. Low-viscosity bulk fill RBCs have lower mechanical properties than all other types of analysed materials. All bulk fill RBCs (except SonicFill) are more translucent for blue light than conventional RBCs., Significance: Although bulk fill RBCs are generally more translucent, the practitioner has to follow the manufacturer's recommendations on curing technique and maximum incremental thickness.

Objectives: The aim of this study was to assess the effect of different resin cement shades on the opacity and color difference of ceramics and to determine the polymerization efficiency of the resin cement at different shades after curing through ceramics., Methods: Two different ceramics (IPS e.max Press and IPS Empress(®)CAD, Ivoclar Vivadent) were used for this study. A light-cured veneer luting resin (Variolink Veneer, Ivoclar Vivadent) in four different shades of HV+1, HV+3, LV-1, and LV-3 was used for the colorimetric measurements. The color and spectral reflectance of the ceramics were measured according to the CIELab color scale relative to the standard illuminant D65 on a reflection spectrophotometer (ColorEye7000A, USA). Color differences (ΔE values) and the contrast ratios (CR) of the different groups of samples were calculated. In order to analyse the polymerization efficiency of the resin cements, the micromechanical properties of the resins were measured with an automatic microhardness indenter (Fisherscope H100C, Germany). The results were analysed using one-way ANOVA and Tukey's HSD post hoc tests (SPSS 18.0)., Results: The one-way ANOVA test showed that the values of ΔE and CR of the different specimen groups were significantly different (p<0.05). Group 1 (20.7 ± 0.5) (IPS-CAD without resin cement) exhibited the highest and group 10 (14.8 ± 0.5) (e.max:HV+3) exhibited the lowest ΔE value. Significant differences in the micromechanical properties were identified among the tested resin cements in different shades (p<0.05)., Conclusions: Resin cement shade is an important factor for the opacity of a restoration. Furthermore, the resin shade affects the micromechanical properties of the underlying resin cement., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

This study evaluated a new enzyme solution (SFC-V) for dentin caries removal, and obtained results were compared with Carisolv. Both solutions were used with a prototype plastic instrument - this being a modified technique for Carisolv. Five carious deciduous teeth were sectioned, and both treatments were applied alternately to each half. Micro-CT observations showed that both treatments resulted in removal of the outer demineralized dentin layer: 28.6% for SFC-V and 28.2% for Carisolv. As for the remaining demineralized dentin, thicknesses of 0.27 microm (SFC-V) and 0.31microm (Carisolv) were observed with no statistically significant differences. FE-SEM analysis revealed that the use of Carisolv resulted in a rougher surface; whereas after SFC-V enzymatic treatment, an organized dentin collagen network with open tubules and few signs of bacteria were observed. In summary, the experimental enzymatic solution and the modified Carisolv treatment removed comparable amounts of carious dentin but with differing resultant surface morphologies.