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Background: Coronal restoration of endodontically treated teeth (ETT) with mesio-occluso-distal (MOD) cavities is of a great importance in long-term success of the treatment. This study evaluated the effect of fiber reinforcement on the fracture resistance (FR) of ETT restored with flowable or paste bulk (PB)-fill composite resin compared to conventional composite (CC) resin., Materials and Methods: In this in vitro experimental study, eighty maxillary premolars were divided into eight groups ( n = 10). The first group was left intact (G 1 ) and the other groups received MOD cavities along with endodontic treatment. G 2 : Remained unrestored while the other experimental groups were restored with three types of composite resin with or without fiber insertion. G 3 : CC resin, G 4 : PB fill, G 5 : Flowable bulk fill (FB). G 6 : Fiber + CC, G 7 : Fiber + PB, and G 8 : Fiber + FB. FR was tested at crosshead speed of 1 mm/min and recorded in Newton. Data were analyzed using one-way analysis of variance and Tukey's tests at significance level of P < 0.05., Results: G 1 and G2 revealed the highest and the lowest FR, respectively. The mean FR of the testing groups in Newton was as follows: G 1 = 1204.8 A , G 2 = 352.1 C , G 3 = 579.6 BD , G 4 = 596.7 BD , G 5 = 624.9 BDE , G 6 = 858.3 E , G 7 = 529.6 CB , and G 8 = 802.5 DE . Different uppercase letters indicate the significant difference between the groups., Conclusion: The effect of fiber insertion on FR depended on the type of composite resin; the highest reinforcing effect was obtained in the CC resin + fiber, followed by bulk-fill flowable + fiber, and flowable bulk (FB)-fill composite resin. The strength of the former was significantly higher than the conventional and PB fill with and without fiber., Competing Interests: The authors of this manuscript declare that they have no conflicts of interest, real or perceived, financial or non-financial in this article., (Copyright: © 2021 Dental Research Journal.)

Aim: To assess the effect of acid‐etching duration time on the compressive strength, microstructure and shear bond strength of All‐Bond Universal adhesive to MTA‐Angelus (AMTA), and Biodentine (BD). Methodology: Forty‐eight cylindrical specimens (4 mm in diameter, 6 mm in height) of AMTA in four groups and 48 specimens of BD in four groups (n = 12) were prepared and stored for 72 h. The control groups were unetched whilst the three experimental groups were acid‐etched for 5, 10 and 15 s, respectively, followed by compressive strength testing. The effect of the various acid‐etching times on surface micromorphology was evaluated under a scanning electron microscope. Similar groups were bonded using All‐Bond Universal and Aelite Flo and shear bond strength was tested. Data were analysed using two‐way ANOVA and Tukey tests. Results: 10‐s and 15‐s acid‐etching reduced the compressive strength of AMTA and BD (P < 0.001), while 5‐s etching did not (P ≤ 0.86). In all the groups, BD had greater compressive strength compared to AMTA. Contrary to BD, the three etched AMTA groups had significantly higher shear bond strength compared to the control group (P < 0.001), with no significant differences between them. The etched groups of AMTA had shear bond strengths comparable to all the BD groups. Scanning electron microscope observations indicated variable surface morphologies such as remnant crystals and cracking/eroding in all our groups of AMTA; though these differences were less prominent for BD. Conclusions: Shortening the acid‐etching time to 5 s resulted in a beneficial effect in terms of resin bonding for AMTA while preventing the detrimental effect of 10‐s and 15‐s etching on the compressive strength of AMTA and BD. However, the three etching times had no effect on resin–BD bond. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of the application sequence of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste (MI paste) on shear bond strength (SBS) of 2 etch-and-rinse resin cements to dentin., Materials and Methods: Sixty extracted human maxillary premolars were cut to expose the mid-coronal dentin surfaces. The teeth were randomly divided into 6 groups (n = 10), based on the resin cement used and CPP-ACP application. In groups 1-3, Excite DSC/Variolink II and in groups 2-4, One-Step Plus/Duolink was bonded to dentin. There were 3 groups for each cement as follows: with no treatment as a control; 3-minute application of CPP-ACP before acid etching (CPP-ACP/Etching); 3-minute application of CPP-ACP after acid etching (Etching/CPP-ACP). After storage in distilled water at 37°C for 24 hours, SBS test was performed. Data were analyzed with 2-way ANOVA and post-hoc Tukey test (α = 0.05)., Results: CPP-ACP application on the dentin before and after acid etching significantly decreased the SBS of OS/Duolink (13.60 and 14.71 MPa, respectively vs. control; 21.21 MPa, p < 0.001); however, it did not influence the SBS of Excite DSC/Variolink II (25.14 MPa) before acid etching (27.37 MPa) or after acid etching (26.41 MPa, p > 0.388). The application sequence of CPP-ACP did not influence the SBS of etch-and-rinse resin cements evaluated., Conclusion: CPP-ACP applications may lower the SBS in some etch-and-rinse resin cements, and timing of applications makes no difference., (© 2019 by the American College of Prosthodontists.)

Purpose: To see whether applying four different liners under short fiber-reinforced composite (SFRC), everX Posterior, compared to conventional composite resin, Z250, affected their strengthening property in premolar MOD cavities., Materials and Methods: Mesio-occluso-distal (MOD) cavities were prepared in 120 sound maxillary premolars divided into 10 groups (n = 12) in terms of two composite resin types and 4 liners or no liner. For each composite resin, in 5 groups no liner, resin-modified glass ionomer (RMGI), conventional flowable composite (COFL), self-adhesive flowable composite resin (SAFL), and self-adhesive resin cement (SARC) were applied prior to restoring incrementally. After water storage and thermocycling, static fracture resistance was tested. Data (in Newtons) were analyzed using two-way ANOVA (α = 0.05)., Results: Fracture resistance was significantly affected by composite resin type (p = 0.02), but not by the liner (p > 0.05). The interaction of the two factors was not statistically significant (p > 0.05). SFRC exhibited higher fracture strength (1470 ± 200 N) compared to conventional composite resin (1350 ± 290), irrespective of the application of liners. Application of SARC and SAFL liners led to a higher number of restorable fractures for both composite resins., Conclusions: The four liners can be used without interfering with the higher efficacy of SFRC, compared to conventional composite resins, to improve the fracture strength of premolar MOD cavities., (© 2018 by the American College of Prosthodontists.)

This study evaluated the effect of fiber inserts combined with composite resins on enamel and dentin margin microleakage. The fiber inserts were used with high- (x-tra fil) and low-viscosity (x-tra base) bulk-fill composite resins and as well as conventional composite resins (Grandio and Grandio Flow). In 96 sound, recently extracted molars, 2 standardized Class II cavities were prepared. The teeth were randomly divided into 8 groups of 12 teeth each, based on composite resin type and presence or absence of fiber inserts: groups 1 and 2, x-tra fil with and without fiber inserts, respectively; groups 3 and 4, x-tra base with and without fiber inserts; groups 5 and 6, Grandio with and without fiber inserts; and groups 7 and 8, Grandio Flow liner (gingival floor)/Grandio (remainder of cavity) with and without fiber inserts. In all the groups, a 2-step etch-and-rinse adhesive was used. The specimens were processed in a dye penetration technique to determine microleakage percentages. Data were analyzed with analysis of variance, Tukey, and t tests. There was significantly less leakage at the enamel margins than the dentin margins. Fiber reinforcement significantly decreased enamel microleakage in all the groups, with no significant differences among the groups. Concerning dentin microleakage, there were no significant differences among the 4 groups without fiber inserts, while a significant difference was detected in groups 2 (x-tra fil plus fiber) and 8 (Grandio Flow plus fiber/Grandio). Fibers significantly improved dentin sealing in groups 2 and 8. These findings suggest that a fiber insert reinforcing bulk-fill and conventional composite resins might improve enamel sealing in shallow Class II cavi-ties. The effect of fiber reinforcement on the dentin margins of deep cavities depended on the viscosity of the composite resins; fiber reinforcement was effective for flowable bulk-fill and conventional composite resin restorations., Competing Interests: Disclaimer: The authors report no conflicts of interest pertaining to the products or companies discussed in this article.

This study investigated the microleakage of Class II composite restorations with composite resin liners. Standardized box cavities were prepared on the mesial and distal surfaces of 84 extracted intact human molars. Proximal margins were located in enamel (occlusal) and 1.0 mm apical to the cementoenamel junction (gingival). The teeth were randomly divided into 6 groups (n = 28 cavities) and restored with Filtek Z350 nanohybrid composite resin (FZ). The test groups were lined with a conventional flowable composite resin, Premise Flowable (PF), or 1 of 2 self-adhesive composites (SACs): Vertise Flow (VF) or Clearfil SA luting cement (CSA) with or without their respective self-etching adhesives: Optibond All-in-One (OB) or Clearfil SE Bond (CSE). The adhesive/lining procedure was performed as follows: OB/FZ (control), OB/PF/FZ, VF/FZ, OB/VF/FZ, CSA/FZ, or CSE/CSA/FZ. Microleakage was evaluated at the occlusal and gingival margins using a dye penetration technique and quantitative assessment. Kruskal-Wallis and Mann-Whitney U tests were used to analyze the data at the significance level of α = 0.05. None of the restorative techniques was capable of preventing microleakage completely. The greatest amount of microleakage was detected in the VF/FZ and CSA/FZ groups at both margins (P < 0.02). Among the groups placed with a bonding agent, OB/VF/FZ showed significantly greater values of microleakage at the occlusal margins than did OB/FZ, OB/PF/FZ, and CSE/CSA/FZ (P < 0.05). At the gingival margins, the OB/PF/FZ group exhibited the least leakage compared with the OB/VF/FZ and CSE/CSA/FZ groups (P < 0.001). The results indicated that the additional application of bonding agents improved the marginal sealing of SACs in Class II composite restorations., Competing Interests: Disclaimer: The authors have no financial, economic, commercial, or professional interests related to topics presented in this article.

Aim: The objective of this study was to investigate the cytotoxic effects of new nanohybrid composite, giomer, conventional and resin modified and silver reinforced glass ionomer cements and compare the biocompatibility of these dental materials in cell culture., Study Design: Five cylindrical specimens were made of each material, using a mold (2mm. thick and 5 mm in diameter). For HGF, cells were cultured in RPMI-1640 medium. After attaining 80% confluence, cells were treated with different doses of five tested materials for 24h. Then cell cytotoxicity was assessed using MTT assay. The data were analyzed using Kruskal-Wallis and Dunn test., Results: The materials evaluated on HGF cells, showed significantly more cytotoxicity in silver reinforced glass ionomer but nanohybrid composite shows mild cytotoxic effect. However, giomer shows no significant cytotoxicity and conventional and resin modified glass ionomer enhance cell proliferation., Conclusions: Silver reinforced glass ionomer induced a significant high cytotoxic effect over a wide range of concentration. Therefore, higher attention should be focused on this restorative dental material, which should be chosen for further investigations.

Statement of the Problem: Sufficient adhesion between silorane/methacrylate-based composites and methacrylate impregnated glass fiber increases the benefits of fibers and enhances the mechanical and clinical performance of both composites., Purpose: The aim of this study was to evaluate the compatibility of silorane and methacrylate-based composites with pre-impregnated glass fiber by using flexural strength (FS) test., Materials and Method: A total of 60 bar specimens were prepared in a split mold (25×2×2 mm) in 6 groups (n=10). In groups 1 and 4 (control), silorane-based (Filtek P90) and nanohybrid (Filtek Z350) composites were placed into the mold and photopolymerized with a high-intensity curing unit. In groups 2 and 5, pre-impregnated glass fiber was first placed into the mold and after two minutes of curing, the mold was filled with respective composites. Prior to filling the mold in groups 3 and 6, an intermediate adhesive layer was applied to the glass fiber. The specimens were stored in distilled water for 24 hours and then their flexural strength was measured by 3 point bending test, using universal testing machine at the crosshead speed of 1 mm/min. Two-way ANOVA and post-hoc test were used for analyzing the data (p< 0.05)., Results: A significant difference was observed between the groups (p< 0.05). The highest FS was registered for combination of Z350 composite, impregnated glass fiber, and application of intermediate adhesive layer .The lowest FS was obtained in Filtek P90 alone. Cohesive failure in composite was the predominant failure in all groups, except group 5 in which adhesive failure between the composite and fiber was exclusively observed., Conclusion: Significant improvement in FS was achieved for both composites with glass fiber. Additional application of intermediate adhesive layer before composite build up seems to increase FS. Nanohybrid composite showed higher FS than silorane-based composite.

Aim: This study evaluated the simultaneous effect of extended etching time and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing paste application on shear bond strength (SBS) of etch-and-rinse adhesive to caries-affected-dentin (CAD)., Materials and Methods: Fifty human third molars were used; 10 normal in group 1 and 40 caries-affected teeth in groups 2 to 5. In the CAD groups, teeth were randomly assigned into four groups (n = 10). In groups 2 and 4, phosphoric acid etching for 15 and 45 seconds was used and in groups 3 and 5, after 15 or 45 seconds etching respectively, CPP-ACP containing paste (MI paste) was applied for 3 minutes. After rinsing, single bond adhesive system and Z250 composite were used for resin composite build-up in all groups. After storage, SBS test was measured at cross head speed of 0.5 mm/min. Data were analyzed using one/two-way ANOVA and Tukey HSD test (α = 0.05)., Results: Normal dentin groups showed the highest SBS among different groups. There was a statistically significant difference between different etching times in CAD groups (p < 0.05), but there were no significant differences between SBS of SB adhesive to CAD with or without CPP-ACP pretreated in both etching times. Most of the failure modes were adhesive except in groups 1 and 5 which cohesive failure in composite was also observed., Conclusion: The results of our study indicated that extended etching time up to 45 seconds could enhance the SBS of CAD and approach nearly to SBS of normal dentin. Moreover, MI paste pretreatment had not significant effect on SBS of etch-and-rinse adhesive in CAD., Clinical Significance: Simultaneous application of extended etching time and CPP-ACP containing paste may be a suggested method in increasing the SBS of adhesive to CAD.

Statement of the Problem: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) increases the mineral content of tooth structure. This may enhance the chemical bonding of glass ionomer cements (GIC) and marginal sealing of their restorations., Purpose: The aim of this study was to evaluate the effect of CPP-ACP paste pretreatment on the microleakage of three types of GIC., Materials and Method: In this study, 72 Class V cavities were prepared on the buccal and lingual surfaces of molars with occlusal margins in enamel and gingival margins in root. The cavities were divided into 6 groups. Cavities in group 1 and 2 were restored with Fuji II, group 3 and 4 with Fuji II LC, and group 5 and 6 with Ketac N100 with respect to the manufacturers' instructions. In groups 2, 4 and 6, CPP-ACP containing paste (MI paste) was placed into the cavities for 3 minutes before being filled with GIC. The teeth were thermocycled, stained with dye, sectioned, and scored for microleakage under stereomicroscope. Kruskall-Wallis and Chi-Square tests were used to analyze the data., Result: There were no statistically significant differences between the control and the CPP-ACP pretreatment groups in enamel and dentin margins. In pairwise comparisons, there were no significant differences between the control and the experimental groups in enamel margin, and in dentin margins of G1 and 2, G5 and 6; however, a significant differences was detected in dentin margins between G3 and 4 (p= 0.041)., Conclusion: CPP-ACP paste pretreatment did not affect the microleakage of Fuji II and Ketac N100 in enamel or dentin, but decreased the microleakage in dentine margins of Fuji II LC when cavity conditioner was applied before surface treatment.

Background: Elimination of water entrapment in hybrid layer during bonding procedure would increase bonding durability., Aims: This study evaluated the effect of oxalate desensitizer (OX) pretreatment on bond strength of three one-bottle adhesives to ethylene-diamine tetra acetic acid (EDTA)-conditioned dentin under dry bonding., Materials and Methods: Three adhesive systems, One-Step Plus (OS), Optibond Solo Plus (OP) and Adper Single Bond (SB) were bonded on dentin surfaces under four bonding conditions: (1) Wet-bonding on acid-etched dentin, (2) wet bonding on EDTA-conditioned dentin, (3) dry bonding on EDTA-conditioned dentin, (4) dry bonding associated with OX on the EDTA-conditioned dentin. After storage and thermo cycling, shear bond strength test was performed. Data were analyzed using two-way analysis of variance and Tukey tests., Results: Wet bonding with EDTA or acid etching showed similar bond strength for test adhesives. Dry bonding with EDTA significantly decreased the bond strength of OS, but it had no effect on the bonding of OP and SB. OX application in the forth bonding condition, in comparison with the third condition, had a negative effect on the bond strength of OP, but not influence on OS and SB., Conclusions: The use of an OX on EDTA-conditioned dentin compromised the bonding efficacy of OS and OP under dry bonding but compatible for SB.

Purpose: This study investigated whether the tubular occluding effect of oxalate desensitizer (OX) during adhesive cementation improved bonding of a self-etch and two etch-and-rinse resin cements to dentin after 6 months., Methods: A flat dentin surface was prepared on 120 extracted premolars, which were randomly divided into six groups of 20 teeth each according to the adhesive resin cement system used: ED primer II/Panavia F2.0, Excite DSC (Ex DSC)/Variolink II, and One-Step Plus (OS Plus)/Duolink, with or without OX (BisBlock) application. After cementation of an indirect composite rod, two subgroups (n=10) were tested after 24 h and 6 months of water storage plus thermocycling, and shear bond strengths were recorded in MPa., Results: Statistical tests showed that although oxalate had a borderline significant negative effect on initial bonding of ED primer II/Panavia F2.0, it significantly improved bonding durability (p<0.05). OX severely compromised the initial bond strength of Ex DSC/Variolink II (p<0.001) but had no effect on the reduction in bonding after aging. OX was compatible with OS Plus/Duolink and did not affect the loss of bonding strength after 6 months (p>0.05)., Conclusion: Combining an oxalate desensitizer with three types of resin cements had different effects on bond strength to dentin after aging, depending on the interaction of oxalate with the adhesive system associated to the resin cement., (Copyright © 2011 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.)

Purpose: This study evaluated the effect of resin coating and chlorhexidine (CH) on microleakage of two resin cements (Panavia F2.0, Nexus 2) after water storage., Materials and Methods: Class V cavities were prepared on the facial and lingual surfaces of 120 intact human molars with gingival margins placed 1 mm below the cementoenamel junction. Indirect composite inlays were fabricated. The specimens were randomly assigned into six groups (n = 40). Indirect composite inlays (Gradia) were cemented as follows: Group 1 (control): inlays were cemented with Panavia F2.0 according to the manufacturer's instructions. Group 2: the ED-primed (ED Primer, Kuraray Dental, Tokyo, Japan) dentin was coated with a resin layer before cementation of the inlays with Panavia F2.0. Group 3: a 2% CH solution was applied before bonding with Panavia F2.0. Group 4: after CH application, the primed dentin was coated with a resin layer before cementation with Panavia F2.0. Group 5: (control) after applying Optibond Solo Plus, the inlays were cemented with Nexus 2. Group 6: after etching, CH was applied, and cementation was performed similarly to group 5. Half the specimens in each group were stored in distilled water for 24 hours, while the other half were stored in distilled water for 6 months. After storage, the teeth were placed in 1% methylene blue dye for 24 hours, sectioned, and evaluated under a 20× stereomicroscope. Dye penetration was scored using 0 to 3 criteria. Data were analyzed using nonparametric tests., Results: Resin coating of ED primer for Panavia F2.0 significantly reduced microleakage at the gingival margins after 6 months (p < 0.05). CH application in Panavia F2.0 did not lead to a significant difference in the microleakage at both margins, after 24 hours and 6 months (p > 0.05). The application of CH showed significantly less microleakage than that of the control group at the gingival margins of Nexus 2 after 6 months. In general, gingival margins showed more microleakage than occlusal margins., Conclusion: An additional resin layer applied to a self-etch cement can improve long-term dentinal sealing for indirect restorations, while CH cannot; however, CH reduces gingival microleakage in an etch-and-rinse cement after aging., (© 2011 by The American College of Prosthodontists.)

Objective: Evaluating the effect of resin coating and chlorhexidine on microleakage of two resin cements after water storage., Materials and Methods: Standardized class V cavities were prepared on facial and lingual surfaces of one hundred twenty intact human molars with gingival margins placed 1 mm below the cemento-enamel junction. Indirect composite inlays were fabricated and the specimens were randomly assigned into 6 groups. In Groups 1 to 4, inlays were cemented with Panavia F2.0 cement. G1: according to the manufacturer's instruction. G2: with light cured resin on the ED primer. G3: chlorhexidine application before priming. G4: with chlorhexidine application before priming and light cured resin on primer. G5: inlays were cemented with Nexus 2 resin cement. G6: chlorhexidine application after etching. Each group was divided into two subgroups based on the 24-hour and 6-month water storage time. After preparation for microleakage test, the teeth were sectioned and evaluated at both margins under a 20× stereomicroscope. Dye penetration was scored using 0-3 criteria. The data was analyzed using Kruskal-Wallis and complementary Dunn tests., Results: There was significantly less leakage in G2 and G4 than the Panavia F2.0 control group at gingival margins after 6 months (P<0.05). There was no significant differences in leakage between G1 and G3 at both margins after 24 hours and 6 months storage. After 6 months, G6 revealed significantly less leakage than G5 at gingival margins (P=0.033). In general, gingival margins showed more leakage than occlusal margins., Conclusion: Additionally, resin coating in self-etch (Panavia F2.0) and chlorhexidine application in etch-rinse (Nexus) resin cement reduced microleakage at gingival margins after storage.

Objective: This study investigated the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on the shear bond strength (SBS) of a universal adhesive in self-etch mode to demineralized dentin. Methods: Seventy-five dentin specimens were randomly divided into five groups (n=15) as follows: Group 1, intact dentin; Group 2, demineralized dentin receiving no remineralization agent; and Groups 3-5, demineralized dentin receiving CPP-ACP for 30, 90, and 180 seconds, respectively. All groups were bonded by Adper Single Bond Universal adhesive in self-etch mode. After 24 hours, the SBS test was conducted, and failure modes were recorded. The data were analyzed by one-way ANOVA, Tukey post-hoc test, and chi-square test at the significance level of P<0.05. Results: The highest and lowest mean SBS values were observed in groups 1 (intact dentin: 29.58 ± 8.13 MPa) and 2 (demineralized dentin: 13.41 ± 4.85 MPa), respectively. ANOVA revealed a significant difference in SBS among the groups (P< 0.001). A pairwise comparison revealed that the SBS of demineralized groups (groups 2-5) was significantly lower than that of the intact samples (P< 0.05). Group 5, with CPP-ACP, applied for 180 seconds, showed a significantly higher SBS (20.74 ± 4.54 MPa) compared to group 2 (P< 0.05). Conclusions: Applying CPP-ACP paste for three minutes can increase the bond strength of the universal adhesive in self-etch mode to demineralized dentin, whereas shorter application times are not effective. [ABSTRACT FROM AUTHOR]

To establish an acid-etching protocol for Biodentine and Cimmo DTA, evaluating compressive strength, bond strength, surface morphology in scanning electron microscope and failure modes after different etching times. Two test specimens were prepared for each cement and divided into four groups (n = 12) according to the acid-etching time (0, 5, 10 and 15 s). Compressive strength was tested using a universal testing machine, while bond strength was evaluated after bonding with Filtek Bulk Flow resin using Universal ESPE Single Bond adhesive. Failures were classified as surface-adhesive, cement-cohesive, resin-cohesive and mixed. Biodentine showed significantly higher compressive strength than Cimmo DTA (p < 0.001), regardless of acid etch time (p < 0.001). Different acid-etching strategies are required for Biodentine and Cimmo DTA, with Biodentine requiring selective etching and Cimmo DTA requiring a full 15-s etch to optimise bond strength properties., (© 2024 Australian Society of Endodontology Inc.)

Composite resin is universally used for posterior teeth restorations. Fibers have been suggested for the mechanical improvement of the restorations. This study assessed the fracture resistance of class II fiber-reinforced composite restorations and compared it with the fracture resistance of three control groups: (1) healthy teeth, (2) non-fiber-reinforced restorations and (3) unrestored cavities. A search was performed using PubMed, Web of Science and Google Scholar from 15 May to 12 June 2023. Only in vitro studies from the last 10 years were included for this systematic analysis. This study was registered in the PROSPERO database, it followed PRISMA guidelines and the risk of bias was assessed using the QUIN tool. Fracture resistance median values, in Newtons (N), were calculated for the experimental and control groups (95% confidence interval). For pairwise comparison, nonparametric tests (p < 0.05) were applied. Twenty-four in vitro studies met the inclusion criteria. The fracture resistance of the experimental group was 976.0 N and differed (p < 0.05) from all controls. The experimental group showed lower values of fracture resistance than healthy teeth (1459.9 N; p = 0.048) but higher values than non-fiber-reinforced restorations (771.0 N; p = 0.008) and unrestored cavities (386.6 N; p < 0.001). In vitro systematic outcomes evidenced that glass and/or polyethylene fibers improved the fracture resistance of composite restorations. [ABSTRACT FROM AUTHOR]

Background: To assess the shear bond strength (SBS) of four calcium silicate-based cements (CSCs) to composite resin using a universal adhesive in self-etch (SE) and etch-and-rinse (ER) modes and to evaluate surface microstructure and chemical composition of CSCs after acid-etching., Methods: In total, 30 specimens of each cement, Biodentine (BD), mineral trioxide aggregate (MTA) Angelus (MTA-A), ProRoot MTA (MTA-P) and MTA Repair HP (MTA-HP), were prepared and assigned into 2 groups (n = 15) according to universal adhesive (Clearfil Universal Bond Quick) applied in SE and ER mode. After composite resin (Clearfil Majesty Esthetic) was applied, the SBS was measured. Scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) analysis was used to evaluate the changes in surface structure and elemental composition., Results: MTA-P demonstrated significantly higher SBS than all CSCs, except for MTA-HP in the SE mode. The ER mode exhibited significantly higher SBS compared to the SE mode for MTA-P and MTA-A. Acid-etching caused morphological differences and affected elemental distribution., Conclusions: MTA-P may be a more suitable pulp capping material due to its superior SBS compared to BD and MTA-A. The application of a universal adhesive in ER mode may be suggested to increase the SBS of MTA-P and MTA-A to composite resin., (© 2023 Australian Dental Association.)

Objectives. This study aimed to compare the fracture resistance (FR) of severely damaged primary anterior teeth restored with five different post and core systems. Materials and Methods. This in vitro, experimental study evaluated 60 extracted primary maxillary central incisors. The teeth were horizontally sectioned at 1 mm above their cementoenamel junction (CEJ), underwent pulpectomy, and their root canals were filled with Metapex paste. After post space preparation and sealing of root fillings with light-cure glass ionomer (1 mm thickness), the teeth were randomly assigned to five groups (n = 12) of (1) glass fiber post and everX composite (reinforced with short fibers), (2) glass fiber post and bulk-fill composite, (3) everX composite post and core, (4) bulk-fill composite post and core, and (5) Filtek conventional composite post and core. The teeth underwent 5,000 thermal cycles between 5°C and 55°C, and their FR was measured in a universal testing machine (0.5 mm/min, 148°). The mode of failure was also determined. Data were analyzed by ANOVA and Tukey's test at 0.05 level of significance. Results. The FR was the highest in fiber post and everX composite, and the lowest in Z250 conventional composite post and core group (P < 0.001). The FR of fiber post and everX composite group was significantly higher than that of everX composite post and core (P = 0.04), bulk-fill composite post and core (P = 0.001), and Z250 composite post and core (P < 0.001) groups. The frequency of repairable fractures was the highest in glass fiber post plus everX composite (91.66%) and the lowest in Filtek conventional post and core group (66.66%) (P > 0.05). Conclusion. Within the limitations of this in vitro study, the results showed that restoration of severely damaged primary maxillary central incisors with glass fiber post and everX composite reinforced with short fibers enhanced their FR, and increased the chance of reparability in case of restoration fracture. This technique may be recommended for the restoration of primary anterior teeth since it is simple and saves time. [ABSTRACT FROM AUTHOR]

Objective: Due to the importance of the effect of water on the structure of composites, in the present systematic review, the effect of water on the flexural and shear strength of silorane and methacrylate-based composites was investigated. Method: Research articles published in English and Farsi were searched using the relevant terms in PubMed, Web of Science Core, POPLINE, EMBASE, Scopus, CINAHL, PsycINFO, International Bibliography of Social Science, and DoPHER databases. In the initial search, 2345 records were obtained. At the next stage, 1482 records were deleted due to duplication, and all articles that did not meet the inclusion criteria or were inappropriate due to indirect relevance to the topic (739 records) were removed. Then, the full-text of 124 articles was reviewed. Finally, 7 studies that met all inclusion criteria were selected for this review study. Results: Based on the inclusion criteria, 7 studies were selected and examined in more detail. In 3 papers, only one composite (methacrylatebased) was investigated. In all but one of these studies, following water uptake over time, a reduction in the shear or flexural strength of the composites was reported. In four other articles, the effect of water on shear or flexural strength in both types of silorane and methacrylate-based composites was investigated. Examination of the results of these papers showed that although they indicated a reduction in mechanical forces for both composites, the rate of reduction was higher for methacrylate-based composites compared to silorane-based composites. Conclusion: Although there was a decrease in shear or flexural strength of both types of composites, silorane-based composites demonstrated a lower rate of reduction in these forces compared to methacrylate-based composites. Therefore, it can be concluded that following water absorption, the mechanical properties of silorane-base composites change less than methacrylate-based composites. [ABSTRACT FROM AUTHOR]

A review article has been conducted including the main research results and comments referring to flowable dental polymeric materials. To begin with, the synthesis and composition of this category of composites is discussed, revealing the major components of the commercial products in terms of chemistry and proportion. Later, the polymerization characteristics are unfolded regarding the reaction time and rate, volumetric shrinkage and depth of cure for both photocurable and self-curable composites. To continue, some perspectives of the pre-treatment or accompanying processes that a clinician may follow to enhance the materials' performance are described. Fluidity is certainly associated with the progress of polymerization and the in-depth conversion of monomers to a polymeric network. Last, the aspects of radiopacity and translucency are commented on, showing that all flowable polymeric composites satisfy the radiography rule, while the masking ability depends on the fillers' properties and specimen thickness. The reviewing article is addressed to all field scientists and practitioners dealing with flowable dental composites studies or applications. [ABSTRACT FROM AUTHOR]

Introduction: Despite the incredible popularity of dental composites, their application is associated with several difficulties, one of the most important of which is the microleakage phenomenon. Incorporation of silver nanoparticles in composites exerts antibacterial effects; nonetheless, the impact of silver nanoparticles on microleakage has not yet been studied. This research conducted to assess the effect of silver nanoparticles application as a precursor on the microleakage of composite-filled clV cavities using two different approaches of universal bond application. Methods: Sixty non-carious human molars were collected, and clV cavities were provided on the buccal surfaces. The samples were categorized to 4 groups (n=15 in each group) and were restored using four different methods. After placement in 2% basic fuchsin solution for 24 h, permeability was determined between the cavity wall and restorative material in the gingival and occlusal margins. Thereafter, one sample of each group was selected. After preparation, the specimens were analyzed using backscattered electron scanning electron microscopy. Finally, the cytotoxicity was assessed by the Methylthiazolyl- tetrazolium (MTT) assay. Results: In both gingival and occlusal margins, if the silver nanoparticles were used, microleakage significantly decreased (P≤0.001). The addition of silver nanoparticles had no adverse effect on human gingival fibroblasts (HGF) cell viability. Conclusion: It seems that the use of silver nanoparticles in the total-etch method can improve phosphoric acid penetration into dentinal tubules, increases the depth of etching, and promotes the bond quality. [ABSTRACT FROM AUTHOR]

Background: Due to their minimally invasive high-quality adhesive, aesthetic and mechanical qualities, composite resins are the most frequently used materials in modern restorative dentistry. However, polymerization shrinkage and cytotoxicity are still unresolved drawbacks associated with these biomaterials. Purpose: The present study aimed to assess the cytotoxicity of some restorative resin-based materials on gingival mesenchymal stromal cells (gMSCs), assuming that no differences in their behavior will be highlighted. Material and methods: The cytotoxicity of the tested materials was evaluated by comparing the behavior of gMSCs cultured in normal conditions and in association with disc-shaped material samples indirectly through functionality tests (colony-forming unit-fibroblast assay, migratory potential) and directly through the MTT assay. The results were statistically analyzed with the ANOVA test and Tukey's Honest Significant Difference test. Results: According to the MTT assay, there are no statistically significant differences regarding the viability of gMSCs cultured in normal conditions or in the presence of resin-based material samples. On the other hand, the present study identified a significantly reduced number of colonies formed by the gMSCs cultured in association with BF and B discs, compared to that of gMSCs cultured in normal conditions. Also, the migratory potential was significantly lower for control gMSCs when compared to ZE-gMSCs and significantly higher for ZE-gMSCs when compared to BF-gMSCs or BFL-gMSCs. Conclusions: The results of the present study highlight a possible risk of cytotoxicity when using resin based-materials in dental practice, but they cannot be directly extrapolated to in vivo situations. [ABSTRACT FROM AUTHOR]

Introduction: This study was conducted to evaluate and compare the effect of using three adhesive systems on the shear bond strength between composite resin and fresh amalgam. Materials and Methods: Amalgam samples were assigned into three groups according to the adhesive systems being used prior to the composite resin application. Group A (n= 10): universal self-etch bonding system (Single Bond Universal Adhesive, 3M, Neuss, Germany) was applied and light cured. Group B (n=10): universal self-etch bonding was applied and light cured, followed by a thin layer of nanohybrid flowable composite (Tetric N-Flow, Ivoclar Vivadent, Liechtenstein), then light cured. Group C (n=10): self-adhesive dual-cure luting resin cement (Calibra Universal, Dentsply Sirona, Charlotte, NC) was applied in equal quantity for each sample over amalgam surface. Composite resin was then applied by plastic instrument in a single increment to the height of the hole (2 mm), then celluloid strip was placed and light cured. After thermocycling, a shear bond test was performed. Results: Resin luting cement interface showed the higher significant bond strength, followed by universal bonding agent - flowable composite interface. The universal bonding interface group yielded the lowest results. Conclusion: The application of self-adhesive dual-cure luting resin cement resulted in significant increase in bond strength between composite resin and fresh amalgam. [ABSTRACT FROM AUTHOR]

Introduction: Metal nanoparticles may apply to the cavity walls as acceptable antibacterial agents. The present work was conducted to assess the effect of silver nanoparticles (NPs) on the resin cements Shear Bond Strength (SBS) using one self-etch and one etch and rinse resin cement. Materials & Methods: Sixty intact noncarious extracted, human third molars were selected. All teeth were cut out in the middle of dentin thickness. Resin cement samples were randomly assigned to five groups: (A) Duolink cement without any further surface treatment; (B) Duolink cement with silver NPs (0.5%) dentin surface treatment after acid etching and before the One Step Plus (OSP) adhesive system; (C) Duolink cement with silver NPs (0.5%) dentin surface treatment before acid etching and OSP; (D) Panavia F2.0 cement without any further surface treatment; and (E) Panavia F2.0 cement with silver NPs (0.5%) dentin surface treatment. SBS was assessed by using universal testing machine. Then, human gingival fibroblasts (HGF) cells were treated with tested materials. The biocompatibility of resin cement was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. Results: The maximum and minimum of the SBS at the presence of silver NPs were observed in group E (15.81±0.91, P-value<0.01) and group B (12.01±0.15, P-value <0.05), respectively. In comparison with the controls, the resin cements incorporated with 0, 0.2% and 0.5% silver NPs, 20.34%, 22.00% and 22.67% for Panavia F2.0 and 36.84%, 37.34% and 38.17% for Duolink flow - decreased in total cell number, respectively (P-value<0.01). Conclusion: These findings demonstrated that Panavia F2.0 cement with silver NPs dentin surface treatment showed satisfactory result in the SBS compared to Panavia F2.0 cement without any further surface treatment. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to investigate the influence of the operator's experience on the microleakage of two universal adhesives applied in self‐etch (SE) and etch‐and‐rinse (E&R) modes. Materials and methods: Two class V cavities were prepared on the buccal and lingual surfaces of 112 caries‐free extracted human molars and were divided into eight groups based on the combination of the factors "adhesive system" (Tetric N‐Bond Universal Adhesive [TNU]; Scotchbond Universal Adhesive [SBU]), "adhesive strategy" (SE or E&R), and "the operators performing the procedures" (specialists in operative dentistry or intern students). After 24 h of water storage and thermocycling, the marginal microleakage was evaluated using the dye penetration technique and the data were analyzed. Results: In the SE mode, microleakage at the enamel margin for both adhesives was higher in the student group than in the specialist group (p values < 0.05). The operator's skill did not affect the microleakage scores of both adhesives applied in the E&R mode at the dentin and enamel margins or in the SE mode at the dentin margins (p > 0.05). The microleakage score was significantly higher at the dentin margins than the enamel margins for both universal adhesives applied in the E&R mode (p values <0.05). Conclusion: The microleakage values of the universal adhesives applied in the SE mode at the enamel margins were affected by the operator's skill. However, the operator's experience did not affect the microleakage scores of the two universal adhesives applied in the E&R mode at the enamel and dentin margins or in the SE mode at the dentin margins. [ABSTRACT FROM AUTHOR]

The objectives of this study were to examine cytotoxic and genotoxic damage in human BJ fibroblasts caused by three pesticides used worldwide by trypan blue dye exclusion assays and to measure the relative level of phosphorylated histone H2A.X by flow cytometry at different concentrations. Captan-based fungicide and methyl thiophanate-based fungicide (100 and 1000 µΜ) showed immediate cytotoxic effects; furthermore, after 24 h, captan-based fungicide, chlorothalonil-based fungicide and methyl thiophanate-based fungicide caused cytotoxic effects in the concentration ranges of 40–100 µM, 30–100 µM and 150–1000 µM, respectively. All fungicides generated DNA damage in the treated cells by activating ATM and H2A.X sensor proteins. The three fungicides tested generated DNA double-stranded breaks and showed cytotoxicity at concentrations 33, 34, and 5 times lower (captan, chlorothalonil and thiophanate-methyl respectively) than those used in the field, as recommended by the manufacturers. [ABSTRACT FROM AUTHOR]

Introduction: Microleakage is an important property that has been used in assessing the success of any restorative material used in restoring a tooth. Immediate application of a surface coating agent is suggested to protect glass-ionomer cement against moisture contamination and dehydration during early setting. Aim: To compare marginal microleakage of two different Glass Ionomer Cement (GIC)- Conventional GIC and Resin Modified GIC in primary anterior teeth using three surface coating materials. Materials and Methods: An in-vitro study was conducted between January 2014 to October 2017 on freshly extracted 40 anterior primary teeth which were randomly assigned into two main groups (Fuji II GIC and Fuji II LC GIC) with four subgroups (control-no surface coating, A=GC Fují Varnish II, B=GC G-Coat Plus, C=Icon). A standardised Class V cavity preparation was prepared on the labial surface of each tooth. Specimens were coated with two layers of nail varnish, leaving a 1 mm window around the cavity margins and placed in a solution of Methylene blue Dye for 24 hour at 37°C. The teeth were sectioned longitudinally in a bucco-lingual direction of the restorations and evaluated under stereomicroscope to check extent of dye penetration. The results were analysed by ANOVA and Tukey's post-hoc test (p=0.05). Results: It was found that maximum microleakage was seen in group 1 (Fuji II GIC) as compared to group 2 (Fuji II LC GIC) and it was non-significant (p=0.53). Ascending order for mean microleakage for Group 1 was as follows: Control >GC Fuji Varnish >Icon DMG >GC G-Coat and for Group 2: Control >GC Fuji Varnish >Icon DMG >GC G Coat. Icon when compared with Gc coat and Varnish also showed non-significant (p=0.137) difference in Group 2. Conclusion: All three different surface coatings can seal glass ionomer restorations. GC G-Coat Plus has the least microleakage on Resin-Modified GIC (RMGIC) compared to the other surface coatings. This would aid the clinicians to make appropriate decision regarding the choice of material to be used for restoration and coating in anterior primary teeth. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the fracture strength and marginal adaptation of MOD cavities restored with Cention N, bonded Cention N, and resin composite, as well as to investigate the effect of cavity preparation volume on those properties. In this experimental study, 120 human maxillary premolars were randomly divided into six groups according to the type of restoration and cavity volume (n = 20): (I) conservative MOD restored with Cention N, (II) conservative MOD restored with bonded Cention N, (III) conservative MOD restored with Z250 resin composite, (IV) extended MOD restored with Cention N, (V) extended MOD restored with bonded Cention N, and (VI) extended MOD restored with Z250 resin composite. Fracture strength (MPa) was tested using a universal testing machine. To investigate marginal adaptation, polyvinyl-siloxane impressions were taken and poured with epoxy resin. Resin replicas were examined by SEM (×400) for marginal adaptation. ANOVA tests, Tukey's test, and independent t-test were used to analyze data (P ≤ 0.05). Among conservative restorations, the fracture strength of bonded Cention N was significantly greater than that of Cention N (P = 0.001), while in the extended preparations, there was no significant difference between fracture strengths of different types of restorations (P = 0.579). In terms of marginal adaptation, there was no significant difference between different types of conservative restorations (P = 0.232). However, in extended preparations, composite showed significantly lower marginal adaptation than Cention N and bonded Cention N (P = 0.004 and P = 0.045, respectively). Conservative preparations showed significantly greater fracture strength and marginal adaptation compared to extended ones in groups restored with composite. The volume of cavity preparation was shown to be effective in the materials fracture strength and marginal adaptation. Cention N showed promising results in terms of fracture strength and marginal adaptation. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to evaluate the effect of proanthocyanidin (PA) and casein phosphopeptide‐amorphous calcium phosphate (CPP‐ACP) paste on the micro‐shear bond strength (μSBS) durability of an etch‐and‐rinse adhesive to caries‐affected dentin (CAD). Materials and methods: The occlusal surfaces of 80 human molars with occlusal caries were ground to expose flat dentin surfaces with CAD. Then, they were randomly divided into four groups (n = 20) according to the CAD pretreatment. The study groups included no pretreatment, pretreatment with CPP‐ACP for 3 min, pretreatment with PA for 1 min, and pretreatment with PA for 1 min followed by CPP‐ACP for 3 min before adhesive application. After restoring the specimens with composite resin, μSBS testing was performed for half of the bonded surfaces in each group after 24 h and the other half was tested after 6 months of water storage and failure mode analysis was performed. Results: The PA group was associated with a higher μSBS than the control and CPP‐ACP groups after 24 hours (p < 0.05). No significant difference was observed regarding the μSBS of the control and the other groups after 24 h (p > 0.05). No significant difference was observed regarding the μSBS of the PA and PA + CPP‐ACP groups (p > 0.05). The μSBS of the 6‐month specimens was significantly lower than those of the 24‐h specimens for all the groups (p < 0.05) except for the PA group which did not exhibit a significant difference between the two times (p > 0.05). The most common type of failure was mixed failure. Conclusion: PA pretreatment could stabilize the CAD‐resin interface and protect degradation over time. The same effect was not observed for CPP‐ACP or PA + CPP‐ACP. [ABSTRACT FROM AUTHOR]

Background: Restoration of endodontically treated premolar is in high risk for biomechanical failure, and often presents with subgingival margins. Proximal box elevation (PBE) has been used to relocate subgingival cavity outlines. Objective: To evaluate the influence of PBE on fracture resistance and gingival microleakage of premolars with endodontic access cavities following ceramic endocrown. Methods: Eighty sound maxillary premolars with standardized Class II cavities on mesial surfaces were randomly assigned to four groups (n = 20 in each group). Groups E1, E2 and E3, with proximal margins located in dentin/cementum, 2 mm below the cemento-enamel junction (CEJ), simulated subgingival location. Group E4 (supragingival group), with proximal margins located in enamel, 1 mm above the CEJ, was used as the positive control. For margin elevation of the proximal cavities, bulk-fill Smart Dentin Replacement (SDR), a visible light cured resin composite, was applied in group E1, and conventional resin composite (3M Z350 XT, a light-activated composite) was placed in group E2. Group E3 was only treated with a ceramic crown and served as the negative control. In all groups, computer-aided design (CAD) ceramic endocrowns were adhesively inserted, and fracture resistance, failure mode and microleakage were evaluated. Results: A higher fracture resistance value was observed in PBE groups E1 and E2, regardless of the materials used (P = 0.038, and 0.010, respectively, vs E3), and fracture resistance in group E1 was higher than that in group E2. In teeth without PBE, the percentage of catastrophic failures reached 70%. Compared to group E3, a lower frequency distribution of microleakage was detected in supragingival group E4 (P = 0.031). No increased percentage of microleakage was observed in groups treated with PBE. Conclusion: For endodontically treated maxillary premolars restored with ceramic endocrowns, PBE increases fracture resistance but not microleakage. [ABSTRACT FROM AUTHOR]

Aim: This study assesses the effect of matrix metalloproteinases on microtensile bond strength (μTBS) of an etch‐and‐rinse adhesive system. Methods: This in vitro study evaluated 88 extracted premolars. The teeth were sectioned to expose dentin and were then randomly divided into four groups (n = 22). In group 1 (control), dentin surface was etched, and Adper Single Bond 2 was applied. In groups 2–4, dentin surface was etched and chlorhexidine (CHX), 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC), and dimethyl sulfoxide (DMSO) were applied on the surfaces, respectively, and blotted dry. Next, Adper Single Bond 2 was applied and all teeth were built up with Z350 composite. In each group, half the samples immediately and the other half after 10,000 thermal cycles underwent μTBS test. Data were analyzed using ANOVA and Tukey's test (α =.05). Results: In thermocycled samples, maximum μTBS was noted in CHX group followed by DMSO, EDC, and control group (p <.001). The thermocycled μTBS of composite to dentin was significantly higher in CHX group compared with EDC, DMSO, and control groups (p <.001) but was not significantly different in EDC and DMSO groups (p =.498). Conclusion: The thermocycled μTBS obtained by the application of CHX, EDC, and DMSO was significantly higher compared with the value to the control group. [ABSTRACT FROM AUTHOR]

Aim: The purpose of this study was to compare translucency values and flexural strength of composite resin materials reinforced with two different fibers. Materials and Methods: In this study, two direct composites (Clearfil Majesty Esthetic and Posterior) and an indirect composite (Tescera) used with a non-fiber control group and two fiber-reinforced (EverStick glass fiber and Ribbond polyethylene fiber) composite groups. Thirty specimens were obtained from the entire composites with dimensions of 25×2×2mm³. Translucency parameter values of the specimens were obtained using a spectrophotometer. The flexural strength (MPa) of the specimens was then determined by a three-point bending test at a rate of 1 mm/min until fracture occurred in the specimen using a universal tester. Data were analyzed by Two Way ANOVA and Tukey HSD multiple comparison test (α=0.05). Results: Ribbond group showed similar translucency parameter values with the control group in all composite materials, but the EverStick group showed significantly lower than the control group (p <0.001). The highest mean flexural strength values were seen in the Clearfil Majesty Posterior control group, while the lowest values were seen in the Clearfil Majesty Esthetic Ribbond group. The mean flexural strength values of the control groups for each composite were found statistically significantly higher than the fiber groups. Conclusion: The fiber addition to composite resins may affect the optical and mechanical properties of the restoration. This effect varies depending on the structural properties of composite resin and fiber. This situation should be taken into consideration in the restoration. [ABSTRACT FROM AUTHOR]

An important factor for successful composite restorations is the development of sealed enamel and dentin margins. The efficacy of self-adhering flowable composite in improving marginal adaptation or reducing microleakage is not fully understood. Also the performance of self-adhering flowable composite at different clinical situations was not proofed. The purpose of this review was to evaluate existing evidence to verify the ability of self-adhering composite to provide durable sealed composite restorations and to summarize available evidences as permanent restorative material based on the results of original scientific full-length papers from peer-reviewed journals listed in PubMed from January 2005 to January 2020. The current literature describes promising results of using a self-adhering composite as alternative of conventional resin composite. However, none of the published results describe an application technique or materials of choice that achieved a homogeneous and tight marginal seal. Also available data from clinical researches did not provide solid recommendations to use it as an option for specific clinical situations. Self-adhering composite restorations can be used as alternative to flowable composite. Also, the results of these studies will help guide new studies that can provide insights regarding important factors and effects related to the performance of these new materials. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of Er:YAG etching on topography, microstructure, compressive strength, and shear bond strength (SBS) of All-Bond Universal adhesive to mineral trioxide aggregate-Angelus (AMTA) and Biodentine (BD). Methods and materials: Sixty cylindrical specimens of each cement (AMTA and BD) in five groups were prepared and stored for 72 h. The control groups were non-etched, and four other groups were acid-etched and laser-etched with a pulse energy of 60, 80, or 100 mJ, followed by compressive strength testing. Surface micromorphology and topography were evaluated. Similar groups were bonded using All-Bond Universal with self-etch and etch-and-rinse (acid-etch) approaches, and laser-etch 60, 80, and 100 mJ, and SBS was tested. Data were analyzed using two-way and one-way ANOVA and the Bonferroni post hoc tests (α = 0.05). Results: BD had a significantly higher compressive strength and SBS (except for laser-etch 100) compared to AMTA, regardless of the etching method (p < 0.001). Acid etching and laser etching 100 of both cements and laser etching 80 of BD alone produced a significantly lower compressive strength than that for the other groups. Contrary to BD, for AMTA, all the treatments significantly increased SBS compared to that of the self-etch group. Conclusions: Etching of AMTA was needed for stronger bonding; laser etching with 60 or 80 mJ without compromising compressive strength was recommended. Etching not only did not improve bonding ability of BD, but it also negatively affected the strength of BD. Clinical relevance: To achieve successful combined calcium silicate cement-resin material restoration, an adequate bond between the materials is mandatory. This might be provided with the ultramild adhesive through laser etching without compromising compressive strength, depending on cement composition and laser energy level used. [ABSTRACT FROM AUTHOR]

Background. Due to the effect of pre-heating on the degree of conversion of composite resins and the possible effect on cytotoxicity, the effect of pre-heating of bulk-fill composite resins was investigated on cytotoxicity in this study. Methods. In this study, three different types of composite resin were used, including Tetric N-Ceram Bulk-Fil, Xtrafil, and Xtrabase. From each composite resin, 10 cylindrical samples (5 mm in diameter and 4 mm in height) were prepared, with five samples preheated to 68°C, and the other five samples polymerized at room temperature (25°C). Twenty-four hours after polymerization, cytotoxicity was assessed by MTT assay on human fibroblasts. Statistical analysis of data was carried out with two-way ANOVA and Sidak Post-Hoc. The significance level of the test was determined at 0.05. Results. There was no statistically significant difference between the mean percentage of cytotoxicity in terms of pre-heating (P>0.05), but the cytotoxicity of the studied composite resins was significantly different (P<0.001). The cytotoxicity of Tetric N-Ceram Bulk-fil composite resin was higher than that of the two other composite resins. Conclusion. Pre-heating of bulk-fill composite resin did not affect their cytotoxicity. In addition, the cytotoxicity of different bulk-fill composite resins was not the same. [ABSTRACT FROM AUTHOR]

Introduction: The association of adhesive systems and desensitising agents could influence the values of the bond strength. That is because these desensitising agents cause the obliteration of the tubular holes and minimise the movement of the dentin fluids, promoted by environmental stimulus that tends to cause hydrolysis at the base of the hybrid layer over time. Aim: To evaluate the microtensile bond strength of total-etch (Single Bond II, SB, 3M ESPE, USA) and self-etch (Clearfil SE Bond, SE, Kuraray, Japan) adhesive systems in dentin conditioned after the application of oxalate-based and fluoride-based desensitising agents. Materials and Methods: Discs obtained from human molars were used, which had its occlusal enamel removed to expose flat surfaces of dentin. Six groups were formed, according to the materials used: G1 (control)- hybridization with SB; G2- desensitizer based on oxalate (BisBlock, BB) and SB; G3- desensitizer based on fluoride (Aqua Prep F, AF) and SB; G4 (control)- hybridization with SE; G5- BB and SE; G6- AF and SE. On these surfaces, blocks of composite resin Filtek Z350 of 5 mm high were prepared to obtain sticks of (1x1x10 mm). The samples were stored in deionized water at 37°C for 24h and submitted to microtensile mechanical trial at 1mm/min speed till the fracture. The results were statistically analysed by one-way ANOVA followed by Tukey's post hoc test (p<0.05). results: The mean values of bond strength of the studied groups in MPa (SD) were as follows: G2: 46.48 (4.02), G3: 44.87 (4.68), G5: 39.02 (4.72), G4: 36.95 (3.57), G1: 36.66 (3.42), G6: 32.71 (3.41) which did not show statistically significant differences (p>0.05). Regarding the fractures analysis, the mixed type prevailed. The fracture was on the base region of the hybrid layer for the total- etch adhesive system, and at the top of the hybrid layer for the self-etch system. conclusion: There is no significant difference in bond strength between the combined use of desensitizers with total-etch and self-etch adhesive systems on human dentine. [ABSTRACT FROM AUTHOR]

Background and Objective: Glass ionomer cements (GICs) are the most commonly used restorative material in pediatric dentistry. They have numerous advantages; however, they show some marginal microleakage at the restoration-tooth interface. Various conditioning agents have been tested for alteration or dissolution of smear layer which has been attributed to the occurrence of microleakage; however, very limited studies have been done using primary teeth.Aims: To evaluate and compare the effect of 10% polyacrylic acid and 17% EDTA on marginal microleakage of high-viscosity GIC.Settings and Design: Experimental, in vitro study.Methodology: Class V cavities of standardized dimensions were prepared on 60 primary anterior teeth and were randomly divided into three groups. Except Group I, the cavities of Groups II and III were conditioned with 10% polyacrylic acid and 17% EDTA, respectively. All the 60 teeth were then restored with high-viscosity GIC. The samples were thermocycled and immersed in methylene blue solution for 24 h. The teeth were removed from the stain, rinsed, and sectioned buccolingually and were observed under stereomicroscope at 30× to score the marginal microleakage.Statistical Analysis Used: Kruskal-Wallis test followed by Mann-Whitney post hoc analysis were used to compare the mean marginal leakage scores between the three study groups.Results: Statistical significance difference was found between all the three groups (P < 0.05). The mean marginal microleakage score was maximum for Group I (control group; 3.00), whereas it was the least for Group II (1.30) where 10% polyacrylic was used for conditioning the cavity surface.Conclusion: Among the study groups, none of them was completely devoid of microleakage in all its samples. 10% polyacrylic acid emerged as a better conditioning agent when compared with 17% EDTA in altering or removing the smear layer thereby resulting in better adhesion. [ABSTRACT FROM AUTHOR]

This article presents an important topic in the field of dental medicine. Reconstruction of the contact point in the lateral interdental area is obtained using a large number of type techniques, with different materials and instruments. The centripetal build up technique involves the initial restoration of the proximal absent wall, thus transforming the second-class cavity into a first-class cavity, followed by it's restoration. This technique provide a correct, appropriate contact point and an easy restoration of the occlusal morphology. [ABSTRACT FROM AUTHOR]