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Objective: To measure degree of conversion (DC) of a flowable composite, microtensile bond strength (MTBS) to dentine in the snow-plow technique with/without preheating and temperature in the preheated composite., Materials and Methods: For DC, snow-plow specimens of Filtek Ultimate Flowable (Flow) and Filtek Bulk Fill (Bulk) (3M) were prepared by light-curing composites simultaneously in standardized molds while in control groups light-curing was separate. DC of Flow was measured using micro-Raman spectroscopy. For MTBS, specimens were prepared on dentine of human extracted molars by simultaneous (snow-plow) or separate (control) light-curing. MTBS was measured using a universal testing machine after 24 h and 6 months. Data were analyzed using ANOVA with Tukey's post hoc (α = 0.05)., Results: Increased curing time significantly increased DC in snow-plow from 13.4% ± 11.6% (10 s) to 31.8% ± 4.4% (40 s) albeit significantly lower than controls (p < 0.05). Preheated Bulk improved conversion in snow-plow (44.3% ± 1.7%) and control (50.5% ± 2.6%) (p < 0.05). No significant differences occurred in MTBS between groups (p > 0.05). MTBS values ranged between 66.7 ± 8.4 MPa (snow-plow group&#95;21°C&#95;baseline) and 54.1 ± 15.8 MPa (control&#95;21°C&#95;long-term). Temperature in the preheated Bulk dropped to ~38°C after 30 s., Conclusions: Snow-plow technique, irrespective of preheating, resulted in lower DC of Flow than separate light-curing of composite increments. Snow-plow, irrespective of preheating, resulted in similar initial and long-term MTBS to dentine., Clinical Significance: Clinicians with preference for flowable composite liners in Class II restorations should be aware that the snow-plow technique of simultaneous light-curing of flowable and bulk-fill composite increments affects monomer-to-polymer conversion, albeit no effect on immediate, and long-term bonding to dentine was detected. Preheating sculptable bulk-fill composite improves conversion of the flowable liner in the snow-plow technique but has no detectable effect on bond strength to dentine., (© 2024 Wiley Periodicals LLC.)

This study aimed to (1) comparatively analyze properties of Sr- and Mg-substituted hydroxyapatite (HAP)-based dental inserts; (2) evaluate insert bonding to restorative materials, and (3) evaluate the effect of doped HAP inserts on fracture resistance (FR) of human molars with large occlusal restorations. By ion-doping with Sr or Mg, 3 insert types were obtained and characterized using XRD, SEM, Vickers hardness and fracture toughness. Shear bond strength (SBS) was determined between acid etched or unetched inserts and following materials: Maxcem cement (Kerr); Filtek Z250 (3M) bonded with Single Bond Universal (SBU; 3M) or Clearfil Universal (Cf; Kuraray). Modified Class I cavities were prepared in 16 intact molars and restored using insert + composite or composite only (control) (n = 8/group). FR of restored molars was determined by static load until fracture upon thermal cycling. Fracture toughness was similar between Sr/Mg-doped inserts (0.94-1.04 MPam -1/2 p = .429). Mg-doped inserts showed greater hardness (range 4.78-5.15 GPa) than Sr6 inserts (3.74 ± 0.31 GPa; p < .05). SBS for SBU and Cf adhesives (range 7.19-15.93 MPa) was higher than for Maxcem (range 3.07-5.95 MPa) (p < .05). There was no significant difference in FR between molars restored with insert-containing and control restorations (3.00 ± 0.30 kN and 3.22 ± 0.42 kN, respectively; p > .05). HAP-based inserts doped with Mg/Sr had different composition and mechanical properties. Adhesive bonding to inserts resulted in greater bond strength than cementation, which may be improved by insert acid-etching. Ion-doped HAP inserts did not affect FR of restored molars. In conclusion, HAP-based dental inserts may potentially replace dentin in large cavities, without affecting fracture resistance of restored teeth., (© 2023 Wiley Periodicals LLC.)

Article Title and Bibliographic Information: Bonding of Glass-Ionomer Cement and Adhesives to Silver Diamine Fluoride-treated Dentin: An Updated Systematic Review and Meta-Analysis. Fröhlich TT, Botton G, Rocha RO. J Adhes Dent. 2022;24(1):29-38., Source of Funding: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001., Type of Study/design: Systematic review with meta-analysis of data., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objectives: This systematic review and meta-analysis evaluated the effects of non-thermal atmospheric plasma (NTAP) treatment on dentin wetting and adhesive-dentin bond strength., Data/sources: This report followed the PRISMA 2020 statement. Two reviewers conducted literature search of MEDLINE, Web of Science and Scopus databases up to the end of November 2020. Included in vitro studies compared the effect of NTAP on treated dentin of non-carious, intact, extracted human third molar teeth with different control groups. Studies with no adequate methods, missing data, lack of control group, or those using animal teeth were excluded. The random effects model was used to summarize the treatment effect with standardized mean difference (SMD) and 95% CI. Risk of bias was assessed using the custom Cochrane Collaboration's tool., Study Selection/results: Seventeen studies met inclusion criteria. The effects on dentin wetting were reported in favor of NTAP (SMD -5.38; 95% CI [-6.97, -3.78]; p<0.00001; I2=81%). Regarding adhesive-dentin bond strength, statistically significant differences between the NTAP and control group were in favor of NTAP in the short-term (SMD 1.92; 95%CI [1.35, 2.50]; p<0.00001; I2=97%), and long-term (SMD 3.28; 95%CI [2.46, 4.09]; p<0.00001; I2=97%). A limitation of meta-analysis is moderate heterogeneity caused by methodological differences and lack of data, which was evaluated through risk of bias and sensitivity analysis., Conclusions: NTAP substantially improves dentin wetting and adhesive-dentin bond strength with 30 seconds exposure time and up to 10 mm tip-to-surface distances being sufficient for positive NTAP effects on bonding efficiency., Funding: ON172207 and III41008 from the Ministry of Education, Science and Technological Development, Republic of Serbia. NP is funded by MESTD grant number 451-03-68/2020-14/200024., Clinical Significance: This systematic review and meta-analysis substantiate potential applicability of NTAP treatment of dentin in improving adhesive bonding clinically. Further research should be based on the optimized parameters such as time and distance with additional refinement of NTAP power., (Copyright © 2021. Published by Elsevier Ltd.)

Objectives: The study aims to evaluate the effects of non-thermal atmospheric plasma (NTAP) treatments on dentin wetting and surface free energy (SFE) and compare the effects of NTAP treatment, etch-and-rinse, and self-etch protocols for application of universal adhesives., Materials and Methods: Mid-coronal dentin of intact third molars was used to measure contact angles of distilled water, ethylene-glycol, and diiodomethane and calculate SFE following different NTAP preset treatments (feeding gas consisting of pure He, He + 1% O 2 , He + 1.5% O 2 ), power input (1 or 3 W), and tip-to-surface distance (2, 4, or 8 mm). Contact angles of reference liquids and SFE of dentin following He + 1.5% O 2 at 3-W and 4-mm treatment was compared to phosphoric acid etching. Contact angles of Single Bond Universal (SBU; 3M ESPE) and Clearfil Universal Bond (CUB; Kuraray Noritake) were measured following NTAP, etch-and-rinse, and self-etch protocols., Results: NTAP significantly reduced contact angles of reference liquids and increased dentin SFE compared to untreated dentin (p < 0.05). O 2 intensified the effect of He NTAP (p < 0.05). NTAP and phosphoric acid increased dentin polarity and Lewis base surface characteristics. Phosphoric acid increased contact angles of adhesives compared to the self-etch protocol (p < 0.05). NTAP resulted in lower adhesive contact angles than phosphoric acid, the difference being statistically significant for CUB (p < 0.05). Compared to the self-etch protocol, NTAP slightly reduced CUB contact angle but not that of SBU (p > 0.05)., Conclusions: He NTAP with and without O 2 increased dentin wetting and SFE, surpassing the effect of phosphoric acid and lowering adhesive contact angles. NTAP produced no apparent micro-morphological changes on dentin surface comparable to acid etching., Clinical Significance: NTAP treatment of dentin prior to adhesive application increases dentin wetting and surface free energy facilitating better adhesive distribution on dentin surface compared to phosphoric acid etching and similar to the "self-etch" application protocol.

Objectives: The aim of this study was to test long-term microtensile bond strength (µTBS) of 2 universal adhesives applied to dentin following "total-etch" (TE) or "self-etch" (SE) protocols and aged by direct or indirect water exposure using simulated pulpal pressure., Materials and Methods: Single Bond Universal (SBU, 3M ESPE) or Ipera Bond (IP, Itena) were applied to mid-coronal dentin ("flat dentin") or Class I cavity ("cavity dentin") following TE or SE protocols in 112 extracted human third molars. Sixteen groups (n = 7 per group) were prepared, 8 groups for µTBS measurements after 24 hours, and further 8 groups for measurements after 6 months storage. "Cavity dentin" groups were subjected to simulated hydrostatic pulpal pressure of 15 cm H 2 O using a custom-made device before cutting 1 × 1 mm sticks while "flat dentin" groups were cut into sticks and directly exposed to deionized water., Results: Generally, the TE protocol resulted in highest µTBS values on flat dentin initially for both adhesives (general linear model, P < .05). Long-term storage resulted in significantly lower µTBS values for the TE protocol (P < .05) while the SE protocol showed comparable values after 6 months (P > .05). "Cavity dentin" with simulated pulpal pressure resulted in lower µTBS than "flat dentin" (P < .05). For both adhesives, µTBS was in the range of 19-42 MPa initially and 16-36 MPa after 6 months storage., Conclusions: µTBS to dentin of universal adhesives is more stable in the long term following the SE than TE protocol. Simulated pulpal pressure and cavity-type sample preparation may be recommended for µTBS testing as a more clinically relevant strategy., Clinical Significance: Microtensile bond strength to dentin of universal adhesives appears more stable following the "self-etch" than "total-etch" protocol after long-term degradation. More clinically relevant data may be obtained using simulated pulpal pressure and cavity-type sample preparation in the study design., (© 2018 Wiley Periodicals, Inc.)

Objectives: To compare the degree of conversion (DC) of adhesives initiated by diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) or a camphorquinone/tertiary amine system (CQ/Amine) as well as their 'immediate' micro-tensile bond strength (μTBS) to bur-cut dentine., Methods: DC of Scotchbond Universal ('SBU'; 3M ESPE), its experimental counterpart containing TPO as photo-initiator system, an experimental G-aenial Bond ('Ga-B'; GC) adhesive formulation, and an experimental LUB-102 adhesive formulation ('LUB', Kuraray Noritake), containing as photo-initiatior system either 2wt% CQ along with 2wt% tertiary amine ('SBU&#95;CQ/Amine'; 'Ga-B&#95;CQ/Amine'; 'LUB&#95;CQ/Amine'), or 2wt% TPO ('SBU&#95;TPO'; 'Ga-B&#95;TPO'; 'LUB&#95;TPO'), was determined using Fourier-transform infrared spectroscopy (FTIR), after being cured with a dual-wavelength light-curing unit (bluephase 20i, Ivoclar Vivadent). The same adhesive formulations were applied to bur-cut mid-coronal dentine of intact human molars, and subjected to a μTBS test after 1-week water storage. Besides being applied following a self-etch (SE) application mode, the adhesive formulations SBU&#95;CQ/Amine and SBU&#95;TPO were also applied following an etch-and-rinse (E&R) mode, this both for DS and μTBS measurement., Results: No significant difference in DC was found for any of the adhesive formulations, except for SBU&#95;CQ/Amine&#95;SE and SBU&#95;TPO&#95;SE. For both SBU formulations, a significantly higher DC was reached for the E&R than the SE approach. Regarding μTBS, no significant differences were recorded, except for the significantly higher μTBS measured for SBU&#95;CQ/Amine&#95;E&R and SBU&#95;TPO&#95;E&R., Conclusions: In self-etch adhesives, the photo-initiator TPO may be used instead of CQ/Amine. The curing and 'immediate' bonding efficiency depended on the application protocol (E&R versus SE), but not on the photo-initiator system., Clinical Significance: The photo-initiator TPO may be used in self-etch adhesives instead of CQ/Amine with similar curing and 'immediate' bonding efficiency., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Objectives: To determine the extent of the hybrid layer (HL) of the novel adhesive system (Silorane, 3M ESPE) compared to one-step and etch and rinse adhesive systems, using 2D confocal micro-Raman spectroscopy and SEM., Methods: Silorane adhesive system was compared to two one-step self-etch (G Bond, GC; AdheSE One, Ivoclar Vivadent) and etch and rinse (Excite, Ivoclar Vivadent) as controls. Adhesives were applied to human dentine, cured and sections prepared perpendicular to the flat adhesive-dentine surface. Two-dimensional micro-Raman mapping was performed over 20mumx20mum areas across the adhesive-dentine interface. SEM micrographs of the same specimens were obtained. One-way ANOVA (Tukey's post-test) was used to analyse the differences in HL thickness among the four adhesive systems and the paired t-test to compare the results obtained by micro-Raman and SEM for each adhesive., Results: Silorane adhesive system formed a HL of comparable thickness to methacrylate-based but thicker than the acrylamide-based one-step self-etch adhesives from SEM analysis. A gradual decrease in adhesive penetration was observed in all systems. A 1-mum zone, between the cured primer and bond was identified by Raman but not visualised on SEM. Compared to SEM, HL calculated from Raman data were always greater., Conclusions: Micro-Raman spectroscopy gives a more precise indication of dentine demineralisation and monomer infiltration and highlights the intermediate zone of approximately 1mum between Silorane primer and bond, not visible with SEM at x10,000 magnification. Giving as it does, a compilation of many linear scans it allows HL mean values to be calculated.

Unreacted monomers in adhesive systems may cause a reduction in material properties, an increase in the long-term instability of the restoration, and pulpal irritation. The degree of dentine demineralization, adhesive penetration, and the degree of conversion (DC) across the dentine-adhesive interface of self-etch adhesives were measured using micro-Raman spectroscopy. Two-step, self-etch AdheSE, one-step self-etch AdheSE One, and etch-and-rinse Excite (control) (Ivoclar Vivadent AG, Schaan, Liechtenstein) were studied. Nine human molars were allocated to three groups and a flat dentine surface was prepared. A smear layer was produced by grinding dentine with 600-grit silicone-carbide discs under water. After application and polymerization of the adhesive, teeth were sectioned to produce four 1-mm-thick slices per tooth for micro-Raman spectroscopy. There were statistically significant differences in the depth of dentine demineralization between all adhesives. The depth and degree of demineralization decreased in the order: Excite>AdheSE>AdheSE One. The mean +/- standard deviation (SD) values for DC within the adhesive layer were 85.2 +/- 2.9% (Excite), 81.4 +/- 4.2% (AdheSE), and 54.3 +/- 10.1% (AdheSE One), and within the hybrid layer were 55.2 +/- 22.5% (Excite), 65.1 +/- 16.9% (AdheSE), and 42.0 +/- 16.2% (AdheSE One). All systems showed a discrepancy between dentine demineralization and adhesive penetration. A significant amount of unreacted monomers were associated with all systems but particularly with the etch-and-rinse system.

Objectives: The purpose of this study was to evaluate how evaporation affects the shelf life of a one-bottle universal adhesive. Methods: Three different versions of Scotch-bond Universal (SBU, 3M ESPE, Seefeld, Germany) were prepared using a weight-loss technique. SBUO was left open to the air until maximal weight loss was obtained, whereas SBU50 was left open until 50% of evaporation occurred. In contrast, SBU100 was kept closed and was assumed to contain the maximum concentration of all ingredients. The degree of conversion (DC) was determined by using Fourier transform infrared spectroscopy on different substrates (on dentin or glass plate and mixed with dentin powder); ultimate mi-crotensile strength and microtensile bond strength to dentin were measured as well. Results: DC of the 100% solvent-containing adhesive (SBU100) was higher than that of the 50% (SBU50) and 0% (SBUO) solvent-containing adhesives for all substrates. DC of the adhesive applied onto glass and dehydrated dentin was higher than that applied onto dentin. Even though the ultimate microtensile strength of SBUO was much higher than that of SBU50 and SBU100, its bond strength to dentin was significantly lower. Conclusions: Evaporation of adhesive ingredients may jeopardize the shelf life of a one-bottle universal system by reducing the degree of conversion and impairing bond strength. However, negative effects only became evident after more than 50% evaporation. [ABSTRACT FROM AUTHOR]