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AbstractEvaluate the remnants of blasted alumina particles after cleaning by different protocols on intact, or resin coated dentine substrates, before or after aging. Seventy-eight mid-coronal dentine specimens were prepared. Six of them were kept intact as negative control (NC) group. At the same time, the other seventy-two were divided into three groups. They received three different dentine treatments: (1) sandblasted (S), (2) resin coated and blasted (RS), (3) resin coated, aged one week, and sand blasted (RAS). Subsequently, each group was cleaned via four sub-group protocols: (1) not cleaned, (2) air/water spray (A/W), (3) etched & A/W, and (4) water jet. Finally, five FE-SEM micrographs were taken from each tooth, and the number of remaining Al2O3 particles was counted on each picture. The numerical data were compared with each other using Two Way ANOVA and LSD post hoc tests (α = 0.05). Most Al2O3 particles were detected on uncleaned specimens, while all the other sub-groups displayed very few or no Al2O3 particles. Statistical analyses revealed that the dentine treatment and cleaning protocol significantly affected the remaining Al2O3 particles (p = 0.000 and 0.000, respectively). Moreover, the interaction of dentine treatment and cleaning protocol was statistically significant (p = 0.000). Cleaning protocols (A/W, etching, and water jet) could effectively remove the remnant of Al2O3 particles from the blasted dentine surface, either resin coated or not. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acid etching of La 3 Mn 2 O 7 for oxygen-deficient layered ε-MnO 2 nanosheets (H 2 SO 4 -LLM) • The unique structure of H 2 SO 4 -LLM boosts diffusion mass transfer ability of toluene. • Oxygen vacancy promotes gaseous oxygen utilization and lattice oxygen mobility. • H 2 SO 4 -LLM exhibits an excellent synergistic adsorption-catalytic oxidation effect. • H 2 SO 4 -LLM achieves T 90 at 196 °C and complete oxidation of toluene at 205 °C. Manganese dioxide (MnO 2) stands out as a promising catalyst for toluene degradation yet refining its synthesis for optimal efficiency poses a significant challenge. In this study, we presented an up-bottom synthesis approach for ε-MnO 2 by selectively removing inactive La ions from La 3 Mn 2 O 7 (LLM) through acid etching, yielding stacked nanosheets with enriched oxygen vacancies. The resulting H 2 SO 4 -LLM catalyst exhibited efficient synergistic adsorption-catalytic oxidation effects, attributed to its exceptional specific surface area (307.0 m2/g) and abundant acidic sites, achieving almost 90 % removal of 2000 mg/m3 toluene (T 90) at 196 ℃ and complete oxidation to CO 2 at 205 °C at a space velocity of 18000 mL/(g·h), outperforming most state-of-the-art catalysts for toluene removal. The study elucidates the role of lattice oxygen in catalyzing toluene oxidation and reveals the intricate interplay between oxygen adsorption, lattice oxygen mobility, and redox capability, paving the way for the development of robust catalysts for environmental remediation. [ABSTRACT FROM AUTHOR]

Background: Self-etching has been shown to be beneficial compared to the other resin sealants especially in pediatric practice. The present in-vivo study was designed to clinically evaluate the sealing ability and retention of the self-etching sealant compared to the conventional resin sealant. The aim was to evaluate and compare the retention and marginal integrity of the self-etch and acid etch sealant materials at three, six and twelve-month follow up. Methods: The study was designed as a double blinded, split mouth randomized controlled trial, . In total, 35 children (70 teeth) between 7 and 10 years of age formed part of the study. Group 1 received acid-etch sealant and Group 2 received self-etch sealants. The study participants and the investigator who performed the statistical analysis were blinded to the treatment allocation. All the samples were evaluated at 3, 6, and 12 months. The inter-group and intragroup comparison were carried out using the Chi-Square test and Friedman test with level of significance set at 5% and the P value less than 0.05. Results: Complete retention of sealants was observed in 34.5% of conventional acid etch (group 1) and 22.9% of self-etch samples (group 2) whereas complete loss of sealants were seen in 11.4% of group 1 and 20% of the group 2 samples and intergroup comparison of retention failure was non-significant (p=0.135). In total, 85.7% of the group 1 and 82.9% of the group 2 samples exhibited good marginal integrity with no clinical changes in the enamel around the margins but this was not statistically significant (p=0.5). Conclusions: Sealants with fewer procedural steps and those which provide adequate retention would be ideal for use in children. Thus, self-etch sealants have been found to be effective and efficient as a sealant in the present in-vivo study. Clinical Trials Registry, India registration: CTRI/2019/03/018343 (29/03/2019).

Background: Self-etching has been shown to be beneficial compared to the other resin sealants especially in pediatric practice. The present in-vivo study was designed to clinically evaluate the sealing ability and retention of the self-etching sealant compared to the conventional resin sealant. The aim was to evaluate and compare the retention and marginal integrity of the self-etch and acid etch sealant materials at three, six and twelve-month follow up. Methods: The study was designed as a double blinded, split mouth randomized controlled trial, . In total, 35 children (70 teeth) between 7 and 10 years of age formed part of the study. Group 1 received acid-etch sealant and Group 2 received self-etch sealants. The study participants and the investigator who performed the statistical analysis were blinded to the treatment allocation. All the samples were evaluated at 3, 6, and 12 months. The inter-group and intragroup comparison were carried out using the Chi-Square test and Friedman test with level of significance set at 5% and the P value less than 0.05. Results: Complete retention of sealants was observed in 34.5% of conventional acid etch (group 1) and 22.9% of self-etch samples (group 2) whereas complete loss of sealants were seen in 11.4% of group 1 and 20% of the group 2 samples and intergroup comparison of retention failure was non-significant (p=0.135). In total, 85.7% of the group 1 and 82.9% of the group 2 samples exhibited good marginal integrity with no clinical changes in the enamel around the margins but this was not statistically significant (p=0.5). Conclusions: Sealants with fewer procedural steps and those which provide adequate retention would be ideal for use in children. Thus, self-etch sealants have been found to be effective and efficient as a sealant in the present in-vivo study. Clinical Trials Registry, India registration: CTRI/2019/03/018343 (29/03/2019).

Background: Self-etching has been shown to be beneficial compared to the other resin sealants especially in pediatric practice. The present in-vivo study was designed to clinically evaluate the sealing ability and retention of the self-etching sealant compared to the conventional resin sealant. The aim was to evaluate and compare the retention and marginal integrity of the self-etch and acid etch sealant materials at three, six and twelve-month follow up. Methods: This was designed a randomized controlled trial, with double blind parallel, split-mouth design. In total, 35 children (70 teeth) between 7 and 10 years of age formed part of the study. Group 1 received acid-etch sealant and Group 2 received self-etch sealants. The study participants and the investigator who performed the statistical analysis were blinded to the treatment allocation. All the samples were evaluated at 3, 6, and 12 months. The inter-group and intragroup comparison were carried out using the Chi-Square test and Friedman test with level of significance set at 5% and the P value less than 0.05. Results: Complete retention of sealants was observed in 34.5% of conventional acid etch (group 1) and 22.9% of self-etch samples (group 2) whereas complete loss of sealants were seen in 11.4% of group 1 and 20% of the group 2 samples and intergroup comparison of retention failure was non-significant (p=0.135). In total, 85.7% of the group 1 and 82.9% of the group 2 samples exhibited good marginal integrity with no clinical changes in the enamel around the margins but this was not statistically significant (p=0.5). Conclusions: Sealants with fewer procedural steps and those which provide adequate retention would be ideal for use in children. Thus, self-etch sealants have been found to be effective and efficient as a sealant in the present in-vivo study. Clinical Trials Registry, India registration: CTRI/2019/03/018343 (29/03/2019).

Overview of the updated literature on the classification of adhesives systems and CAD/CAM materials with clinical guidelines to condition various surfaces for bonding to the tooth structure. Searches were conducted in MEDLINE, EMBASE, PubMed, Web of Science, Scopus, Cochrane Library, and Google Scholar using specific keywords. 240 papers were revised, 150 articles were excluded, and 90 were eligible for the review. Most studies concluded the essentiality of bonding E-max, zirconia, and hybrid materials to enhance fracture toughness and fatigue resistance. The success of ceramic bonding depends on the microstructure and surface treatment of the materials. The proper treatment of the intaglio starts with using alumina oxide or hydrofluoric acid. This initial treatment could be followed by monobond salinization, which improves the chemical adhesion. Zirconia-based ceramics have grown lately and become the most prescribed for posterior and anterior teeth. Zirconia can be bonded to the tooth structure using the APC concept and 10 MDP promoting primers. Three hundred adhesive resin systems are currently available in the market, and each is different in chemical composition and clinical bonding strength. Of the three hundred systems, the total-etch system remains the gold standard, especially on the enamel surface. The self-etch adhesive system is favorable on dentin due to lowering the postoperative sensitivity. A new generation of dentin adhesives, called universal or multi-mode adhesives. This system has become popular and can be used either as etch-and-rinse or self-etch adhesives. The chemistry of adhesive systems has changed across generations. The variation of dental tissue is the decisive factor in selecting adhesive systems, resin cement, and ceramic materials. Moreover, a reliable bonding strength necessitates a perfect surface treatment and bonding promoter for tooth and CAD/CAM materials. [ABSTRACT FROM AUTHOR]

Background: Self-etching has been shown to be beneficial compared to the other resin sealants especially in pediatric practice. The present in-vivo study was designed to clinically evaluate the sealing ability and retention of the self-etching sealant compared to the conventional resin sealant. The aim was to evaluate and compare the retention and marginal integrity of the self-etch and acid etch sealant materials at three, six and twelve-month follow up. Methods: The study was designed as a double blinded, split mouth randomized controlled trial, . In total, 35 children (70 teeth) between 7 and 10 years of age formed part of the study. Group 1 received acid-etch sealant and Group 2 received self-etch sealants. The study participants and the investigator who performed the statistical analysis were blinded to the treatment allocation. All the samples were evaluated at 3, 6, and 12 months. The inter-group and intragroup comparison were carried out using the Chi-Square test and Friedman test with level of significance set at 5% and the P value less than 0.05. Results: Complete retention of sealants was observed in 34.5% of conventional acid etch (group 1) and 22.9% of self-etch samples (group 2) whereas complete loss of sealants were seen in 11.4% of group 1 and 20% of the group 2 samples and intergroup comparison of retention failure was non-significant (p=0.135). In total, 85.7% of the group 1 and 82.9% of the group 2 samples exhibited good marginal integrity with no clinical changes in the enamel around the margins but this was not statistically significant (p=0.5). Conclusions: Sealants with fewer procedural steps and those which provide adequate retention would be ideal for use in children. Thus, self-etch sealants have been found to be effective and efficient as a sealant in the present in-vivo study. Clinical Trials Registry, India registration: CTRI/2019/03/018343 (29/03/2019).

Purpose: To determine whether or not re-etching of oxalate-treated dentin and enamel increases microshear bond strength (µSBS) and improves hybridization. Materials and Methods: Two single-bottle etch-and-rinse adhesives, SingleBond (3M/ESPE) and OptiBond S (Kerr), were bonded to deep occlusal dentin and enamel after perfusion under 20 mmHg simulated intrapulpal pressure. For each adhesive tested, the experimental groups were: G1: bonding according to manufacturer's instructions (control); G2: application of oxalate desensitizer (D/Sense Crystal, Centrix) to acid-etched substrate followed by 60 s water rinsing prior to bonding; G3: same as G2, but with a further 15-s re-etching with 35% phosphoric acid before bonding. The microshear bond strength (µSBS) to dentin and enamel was tested (n = 15); a scanning electron microscopic (SEM) analysis of surface topography (n = 2), interface (n = 2), and failure mode was also performed. The data were statistically analyzed using ANOVA and Tukey's tests at p ≤ 0.05. Results: In enamel, both adhesives showed no significant difference in µSBS among groups. In dentin, the highest statistically significant µSBS for both adhesives was recorded for G1, followed by G2, with the lowest values in G3. The predominant mode of failure was adhesive. SEM analysis of the topography after oxalate treatment revealed remnants of calcium oxalate crystals that were removed only from enamel surfaces after re-etching. SEM images of the interface revealed inadequate dentin hybridization in G2 and G3 compared to G1. Conclusion: Re-etching after oxalate treatment compromises bonding of single-bottle etch-and-rinse adhesives to dentin and provides no added benefit to enamel bonding. [ABSTRACT FROM AUTHOR]

Abstract The design of monolithic U Mo fuel elements fabricated from low-enriched uranium for use in high-power research reactors requires bonding of the fuel foil to either Al cladding or a Zr barrier layer. Processing of the U Mo ingot to final foil form has the potential to generate surface layers on the foil that differ from the bulk, metallic U Mo. The interfacial properties between the U Mo and Zr or Al cladding layers will then be determined by these surface layers. We use x-ray photoelectron spectroscopy, cross-sectional scanning electron microscopy, and atomic force microscopy to characterize the composition, oxidation state, and morphology of the surface layers that form after hot rolling and cold rolling depleted U–10 wt% Mo alloy (DU10Mo). A thick uranium nitride layer is observed after hot rolling, although its origin is likely from a previous processing step. The efficacy of acid etching in HNO 3 is compared to that of electropolishing in H 2 SO 4 to remove surface nitride and oxide layers, and both methods are found to be similarly effective. Both laboratory (low humidity) air exposure and longer rinse times in water are shown to promote the formation of surface oxide layers. Exposure of both acid-etched and electropolished DU10Mo foils to humid air (97% relative humidity) for six weeks results in formation of a thick oxide layer due to corrosion. The oxide layer on the acid-etched foil is thicker and more highly oxidized than the oxide layer that forms on the electropolished foil, and these differences in oxidation behavior are attributed to higher surface roughness on the acid-etched foil. In general, Mo is found to play a role as a sacrificial element, typically exhibiting a larger ratio of Mo6+/Mo4+ than U6+/U4+. This is unexpected, given the greater thermodynamic driving force to form U oxides than Mo oxides. Highlights • Surface characterization of monolithic U Mo fuel elements. • Efficacy of acid etching vs. electropolishing to remove surface oxide. • Characterized by x-ray photoelectron spectroscopy and scanning electron microscopy. • Surface roughness enhances oxidation in high humidity environment. [ABSTRACT FROM AUTHOR]

Background and Purpose: The objectives of the study were (1) to compare two techniques of sealant placement using Acid-etch technique and by using an Air abrasive technique, (2) to determine whether particular tooth locations are related to sealant loss or retention. Methodology: 30 children in age group 7-12 years were received sealant on non carious, non filled, occlusal, and buccal pit surfaces of both permanent first mandibular molars (36, 46) two in each subject of treatment groups: 1) Acid etch technique (Group A) and 2) Air abrasion without acid etch (Group B). A total of one hundred and twenty surfaces received sealants, and were evaluated at six months. Results: Rate of complete sealant retention at six months for occlusal surfaces were 89.29% for Acid etching and 78.57% for Air abrasion , and for buccal surface were 50% for Acid etching and 32.14% for Air abrasion. Conclusion: This study suggested that, rates of complete retention on the occlusal and buccal surfaces of both treatment groups were not significant. More research is needed to identify factors contributing to low retention rates on occlusal and buccal surfaces for Air abrasion technique.

Objective: To see whether there is an advantage to using a self-limiting phosphoric acid etchant versus a traditional 34% phosphoric acid etchant for bonding by measuring the depth of etch at multiple time intervals. Materials and Methods: A total of 25 bovine teeth were mounted and etched on the facial surface with two different etchants: standard 34% phosphoric acid and a self-limiting 35% phosphoric acid etchant at varied time intervals of 15, 30, 60, 90, and 120 seconds. Teeth were scanned using a three-dimensional laser confocal scanning microscope prior to etching and scanned again after etching to determine the depth of enamel etched compared to the baseline enamel surface prior to etching. Results: The 34% phosphoric acid etchant etched significantly deeper than the self-limiting etch. Etch times exceeding 30 seconds also etched significantly deeper for both types of etchant. Conclusion: The etch depth of the self-limiting etchant was consistently less than the standard etchant. Both types of etchant etched deeper after 30 seconds, but the depth of etch at 120 seconds was not different than at 60 seconds, indicating that both etchants are somewhat selflimiting in depth. Therefore, there is no advantage to using the self-limiting etchant. [ABSTRACT FROM AUTHOR]

Introduction: Bonding of orthodontic brackets to fluorosed enamel is a challenge for all dental clinicians. The objective of this study was to determine the success of bracket retention in patients with dental fluorosis using a different acid etch protocol. Methods: 12 patients with varying degrees of dental fluorosis were bonded in vivo with a split mouth design with one side of the arch treated with 37% phosphoric acid for 60 seconds and then bonded. The other side of the arch in all patients was pretreated with Opalustre (ultradent) containing 6.6 % hydrochloric acid and silicon carbide micro particles in a water-soluble paste for 45 seconds and then bonded. Results: Over a period of 12 months, 17 bond failures occurred in the side treated with 37% phosphoric acid and 7 bond failures occurred in the side treated with Opalustre containing hydrochloric acid and silicon carbide micro particles. An unpaired t test statistical analysis revealed p=.0108 which is statistically significant by conventional criteria, demonstrating the effectiveness of pretreatment of teeth with Opalustre for orthodontic bonding in cases of dental fluorosis. Conclusions: The rate of bond failure with 37% phosphoric acid is high in patients with dental fluorosis. The rate of bond failure is higher with pretreatment with phosphoric acid than with Opalustre, so Opalustre containing hydrochloric acid can be recommended for pretreatment of teeth with fluorosis for orthodontic bonding. The recommended acid etch protocol also saves chair side time of the orthodontist, improves success rate of the treatment and minimizes cost of the treatment by preventing recurrent bond failures.

Aims: To evaluate shear and tensile bond strengths of the bonded brackets to the enamel surfaces treated with acid and microetcher. Materials and methods: The sample include 30 intact extracted upper left first premolars, the teeth were collected from orthodontics clinic and private clinics. The sample was grouped into three groups (10 teeth for each group), which were: acid etched, microetched at 5mm distance, and microetched at 10mm distance.. Stainless steel brackets (Roth System) were bonded to the buccal enamel surfaces utilizing light cure composite (transbondTM XT) according to the manufacturer instructions. All the groups were thermocycled, the temperature range is 5 + 3 ºC to 50 + 3 ºC with a 30 seconds dwell time in each bath. The shear and tensile bond strengths of the bonded bracket were measured by using the shear and tensile Universal testing machine. The results were analyzed statistically; that include: Descriptive, ANOVA and Duncan’s testes at p≤ 0.05 significant level. Results: It was reveled that the shear and tensile bond strength values of the bonded brackets to enamel treated with the acid were greater significantly than that treated with microetcher. Conclusions: The acid agent is considered the most practical conditioner to the enamel to achieve strong shear and tensile bond strengths.

Background: Calcium silicate cements (CSCs), if used for pulp capping or furcation repair, are covered with a restoration. The role of different time intervals of the conditioning process used for final restorations for new CSCs has not been studied. The aim of this study was to evaluate the effects of acid etching on the compressive strengths of biodentine (BD), endosequence bioceramic root repair material-fast set putty (ERRM-FSP), and ProRoot mineral trioxide aggregate (PMTA) at 24 h or 7 days. Materials and Methods: A total of 144 specimens were prepared (48 per material). For each material, 12 specimens were subjected to acid etching at 24 h or 7 days. Compressive strengths were evaluated in accordance with ISO 9917-1:2007 recommendations. Specimens were crushed along their long axis using a universal testing machine. The maximum load required to fracture each specimen was recorded in megapascals. Compressive strengths were compared with the unetched control groups. Results: For all materials, the compressive strengths were significantly higher at day 7 than at 24 h. There were no statistically significant differences between the control and etched groups at 24 h or 7 days for the materials tested. Overall, the compressive strength was significantly lower for ERRM-FSP than for PMTA and BD. Conclusion: The acid-etching procedure did not affect the compressive strength of BD, ERRM-FSP, or PMTA. However, the postponement of the acid-etching procedure until 7 days after CSC placement is suggested to reduce the possibility of displacement. [ABSTRACT FROM AUTHOR]

We investigated the response of rat bone mesenchymal stem cells (BMSC) placed on the titanium-6aluminium-7niobiuim (Ti-6Al-7Nb) alloy modified by hydrofluoric acid etch combined with subsequent anodic oxidation. Pure titanium (Ti) discs and Ti-6Al-7Nb discs were treated by hydrofluoric acid etch and anodic oxidation, and polished pure Ti discs and Ti-6Al-7Nb discs without surface modification served as controls ( n = 35 in each group). Scanning electron microscopy, atomic force microscopy, and radiographic photoelectron spectroscopy assays were used to detect the properties of the samples’ surface. The morphology, adhesion, proliferation, and alkaline phosphatase activity of BMSC were examined using various techniques of microscopic and biological characterisation. The results showed that both Ti-6Al-7Nb samples and the pure Ti samples showed hierarchical micro/nanotopographies, and fluorine emerged on the surfaces of the samples after modification. The hierarchical micro/nanotopographies significantly increased the spreading, adhesion, and proliferation of BMSC and activity of alkaline phosphatase. In addition, modified samples of Ti-6Al-7Nb showed significantly higher alkaline phosphatase activity than modified pure Ti samples ( p < 0.05). The experiment successfully confirmed that Ti-6Al-7Nb alloy with hierarchical micro/nanotopographies treated by hydrofluoric acid etch and anodic oxidation possessed good biocompatibility, and may be a promising candidate for dental implants. [ABSTRACT FROM AUTHOR]

Background The aim of this study was to investigate the use of phosphoric acid as a surface treatment compared to traditional conditioning agents to dentine bonded with resin-modified glass ionomer ( RMGIC) adhesives. Methods Forty human molars were utilized in microtensile bond strength testing, while another 16 were used for evaluation of the bonded interface with scanning electron microscopy. Three RMGIC adhesives were evaluated: Fuji Bond LC ( GC Corp); Riva Bond LC ( SDI Ltd); and Ketac N100 (3M- ESPE). Surface treatments were 37% phosphoric acid (5 s) or 25-30% polyacrylic acid ( PAA) (10 s), or the manufacturer's method - Fuji Bond LC: Cavity Conditioner (20% PAA + 3% AlCl3 10 s) or Ketac N100 primer: Ketac Nano priming agent (15 s). Teeth were finished with 600-grit SiC paper, surfaces treated and bonded with RMGIC adhesive and stored in distilled water for 24 h then subjected to microtensile bond strength testing. Results Two-way analysis of variance ( ANOVA) revealed adhesion was affected by the 'type of RMGIC adhesive' and 'method of dentine surface treatment' (p < 0.05). The microtensile bond strength of Ketac N100 primer groups was lower than Fuji Bond LC and Riva Bond LC (p < 0.05). Conclusions For RMGIC adhesives a brief etch with phosphoric acid does not adversely effect short-term bond strengths, but is no better than traditional conditioning with PAA. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this in vitro study was to compare the shear bond strength of an airborne-particle abraded zirconia, an acid-etched zirconia (Piranha solution), an Alloy Primer treated zirconia, and a silaned zirconia to enamel, all bonded with a phosphate-methacrylate resin luting agent. Materials and Methods Seventy extracted intact human molars were collected, cleaned, and mounted in autopolymerizing acrylic resin, with the experimental surface of the teeth exposed. The specimens were randomly divided into seven groups of zirconia specimens (4 mm diameter, 2 mm thick). Group 1: Airborne-particle abrasion; group 2: Airborne-particle abrasion and Z-PRIME Plus; group 3: Airborne-particle abrasion and alloy primer; group 4: Piranha solution 7:1; group 5: Piranha solution 7:1 and Z-PRIME Plus; group 6: Piranha solution 7:1 and Alloy primer; group 7: CoJet and silane. All specimens were luted with a phosphate-methacrylate resin luting agent (Panavia F2.0) and stored in distilled water for 1 day, then thermocycled (5°C and 55°C) for 500 cycles and tested for shear bond strength (SBS), measured in MPa, with a universal testing machine at a 0.55 mm/min crosshead speed. All specimens were inspected under a scanning electron microscope to determine mode of failure. The mean values and standard deviations of all specimens were calculated for each group. A one-way ANOVA was performed, and multiple pairwise comparisons were then completed with post hoc Tukey test (alpha = 0.05). Results The airborne-particle abrasion and Z-PRIME Plus group resulted in a significantly higher SBS than the other groups (21.11 ± 6.32 MPa) ( p < 0.001). The CoJet and silane group (15.99 ± 8.92 MPa) and airborne-particle abrasion and alloy primer group (11.07 ± 4.34 MPa) showed high shear bond strength but not statistically significant from the airborne-particle abrasion group (14.23 ± 5.68 MPa). Failure mode was predominately mixed in groups 1, 2, 3, and 7 with islands of retained resin on the zirconia and enamel surfaces; however, groups 4, 5, and 6 showed mostly adhesive failures, which left the zirconia surface free of the adhesive materials. No cohesive failures of the substrates (ceramic, resin, or enamel) were observed. Conclusion Airborne-particle abrasion followed by the application of a zirconia primer produced the highest bond strength to enamel. Therefore, it can be recommended as a promising surface treatment method to achieve a durable bond to densely sintered zirconia ceramics. [ABSTRACT FROM AUTHOR]

This study evaluated the microleakage of brackets bonded by four different enamel etching techniques. Forty freshly extracted human premolars were divided randomly into four equal groups and received the following treatment: group 1, acid etching; group 2, self-etching primer (SEP); group 3, erbium:yttrium-aluminum-garnet (Er:YAG) laser etching; and group 4, erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser etching. After photopolymerization, the teeth were kept in distilled water for 1 month and then subjected to 500 thermal cycles. Then, the specimens were sealed with nail varnish, stained with 0.5% basic fuchsin for 24 h, sectioned, and examined under a stereomicroscope. In addition, they were scored for marginal microleakage at the adhesive-enamel and bracket-adhesive interfaces from the incisal and gingival margins. Statistical analyses consisted of the Kruskal-Wallis test and the Mann-Whitney U test with Bonferroni correction. Microleakage occurred between the adhesive-enamel and bracket-adhesive interfaces in all groups. For the adhesive-enamel surface, a significant difference was observed between group 1 and groups 2 (P = 0.011), 3 (P = 0.002), and 4 (P = 0.000) on the gingival side. Overall, significant differences were observed between group 1 and groups 3 (P = 0.003) and 4 (P = 0.000). In dental bonding procedures, acid etching was found to result in the least microleakage. Since etching with a laser decreases the risk of caries and is time-saving, it may serve as an alternative to acid etching. [ABSTRACT FROM AUTHOR]

Abstract: This study has examined the use of polyvinylphosphonic acid (PVPA) as a potential matrix metalloproteinase (MMP) inhibitor and how brief cross-linking of demineralized dentin matrix that did not affect its mechanical properties enhanced the anti-MMP activity of PVPA. The anti-MMP potential of five PVPA concentrations (100–3000μgml–1) was initially screened using a rhMMP-9 colorimetic assay. Demineralized dentin beams were treated with the same five concentrations of PVPA to collagen and then aged for 30days in a calcium- and zinc-containing medium. The changes in modulus of elasticity, loss of dry mass and dissolution of collagen peptides were measured via three-point bending, precision weighing and hydroxyproline assay, respectively. All tested PVPA concentrations were highly effective (P <0.05) in inhibiting MMP-9. Ageing in the incubation medium did not significantly alter the modulus of elasticity of the five PVPA treatment groups. Conversely, aged dentin beams from the control group exhibited a significant decline in their modulus of elasticity (P <0.05) over time. Mass loss from the dentin beams and the corresponding increase in hydroxyproline in the medium in the five PVPA treatment groups were significantly lower than for the control (P <0.05). PVPA is a potent inhibitor of endogenous MMP activities in demineralized dentin. It may be used as an alternative to chlorhexidine to prevent collagen degradation within hybrid layers to extend the longevity of resin–dentin bonds. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to determine the clinical performance of a two-step self-etch adhesive with and without additional enamel etching technique to advanced non-carious cervical sclerotic lesions. Methods: Twenty-two patients (mean age = 51.5) having at least two pairs of non-carious cervical erosion/attrition/abfraction lesions with incisal or occlusal margins in enamel and gingival margins in dentine/cementum were included in the study. The two-step self-etch adhesive (AdheSE; Ivoclar-Vivadent) was either applied following the self-etch approach on both enamel and dentine (AdheSE non-etch), or a similar application including additional acid-etching of the enamel cavity margins with 37% phosphoric acid (AdheSE etch). Resin composite Point 4 was used for all 104 restorations. Restorations were evaluated at baseline and at one year according to the modified United States Public Health Service (USPHS) criteria. Data were analysed by using McNemar’s test (p <0.05). Results: There were no significant differences in the marginal adaptation both at the cervical and enamel margins between AdheSE non-etch and AdheSE etch groups (p >0.05). At one year, marginal discolouration was evident in the AdheSE non-etch group but it was not statistically significant from the AdheSE etch group (p = 0.12). Postoperative sensitivity was 5% at baseline and reduced to 2% at one year. Conclusions: At one year, the two-step self-etch adhesive with and without additional enamel etching technique showed excellent clinical results to advanced non-carious cervical sclerotic lesions. [ABSTRACT FROM AUTHOR]

Abstract: This study describes a method for combining sandblast-acid etching and micro-arc oxidation to optimise titanium implant surfaces, and examines the effects of these surfaces on osteoblast response. Titanium discs were grouped as: micro-arc oxidised (MAO), sandblast-acid etched and micro-arc oxidised (MAO-SA), micro-arc oxidised and heated (MAO-HT), and untreated smooth surface. The combination of sandblast-acid etching and micro-arc oxidation in the MAO-SA group created an average surface roughness of 2.02±0.15μm compared to the untreated machined surface of 0.31±0.06μm. Scanning electron microscopy observations of the surface structures showed that the irregularly ordered valleys created by sandblast-acid etching remained after micro-arc oxidation and that micropores had also formed. These microstructures provided a better place for osteoblasts to spread compared with the other surfaces. In addition, our results indicated that adherent osteoblasts expressed greater alkaline phosphatase (ALP) activity and osteocalcin (OC) production on MAO-SA surfaces compared with MAO, MAO-HT, and smooth surfaces. The overall results clearly indicate that combining sandblast-acid etching and micro-arc oxidation techniques improves the titanium surface morphology and increases the roughness, which provides an optimal surface for cell differentiation and osseointegration. [Copyright &y& Elsevier]

Aim To evaluate the effect of acid-etch procedures on the compressive strength and surface microhardness of tooth-coloured mineral trioxide aggregate (MTA). Methodology White ProRoot MTA (Dentsply Tulsa Dental) was mixed and packed into cylindrical tubes of 4 mm in diameter and 6 mm in height. Three groups, each of 15 specimens were subjected to an acid-etch procedure either 4, 24 or 96 h after mixing. The compressive strength was measured and compared with unetched control groups. Differences between groups were analysed using the Kruskall–Wallis test. A further batch of cylindrical specimens of 6 mm in diameter and 12 mm in height were prepared for testing surface microhardness. Three groups of 15 specimens were subjected to the acid-etch procedure at either 4, 24 or 96 h following mixing. Data were subjected to one-wayanova. Changes in the surface microstructure before and after the acid-etch procedures were analysed using a scanning electron microscope (SEM). Results There was a general trend for the compressive strength and surface microhardness of specimens to increase with time. In terms of compressive strength, the increase was significant between 4 h and the other time periods for both experimental and control groups ( P < 0.0001); however, there was no significant difference between 24 and 96 h. The increase in surface microhardness was significant between 4, 24 and 96 h ( P < 0.0001). In addition, there was a significant difference between experimental and control groups at all time periods ( P < 0.0001). SEM examination revealed morphological differences between the intact and the etched MTA surfaces. Conclusions Acid-etch procedures affected the compressive strength and surface microhardness of ProRoot MTA. This indicates that it may be better to postpone restorative procedures for at least 96 h after mixing MTA. Etching created surface changes that might have the potential to enhance bonding of resinous materials. [ABSTRACT FROM AUTHOR]

Er-YAG laser irradiation has been claimed to improve the adhesive properties of dentin. We tested the hypothesis that dentin adhesion is affected by Er-YAG laser conditioning. Superficial or deep dentin from human molars was: (a) acid-etched with 35% H3PO4; (b) irradiated with an Er-YAG laser (KaVo) at 2 Hz and 180 mJ, with water-cooling; and (c) laser- and acid-etched. Single Bond (3M ESPE) and Z100 composite (3M ESPE) were bonded to the prepared surfaces. After storage, specimens were tested in shear to failure. Bonded interfaces were demineralized in EDTA and processed for transmission electron microscopy. Two-way ANOVA revealed that conditioning treatment and interaction between treatment and dentin depth significantly influenced shear bond strength results. Acid-etching alone yielded shear bond strength values that were significantly higher than those achieved with laser ablation alone, or in combination with acid-etching. The Er-YAG laser created a laser-modified layer that adversely affects adhesion to dentin, so it does not constitute an alternative bonding strategy to conventional acid etching. [ABSTRACT FROM AUTHOR]

Adhesives and composite technology have made composite resins and polyacid-modified resin-based composites (compomers) very popular as materials to restore primary and permanent anterior and posterior teeth. More conservative preparations can be performed that maintain more tooth structure due to the adhesive properties of the adhesives used with composites and compomers. Meticulous care in the placement of adhesives and, subsequently, resin-based composites and compomers is necessary to produce long-term satisfactory results. The purpose of this paper is to update the current status in regards to dentin-enamel adhesives in primary teeth. [ABSTRACT FROM AUTHOR]

Background: Self-etching has been shown to be beneficial compared to the other resin sealants especially in pediatric practice. The present in-vivo study was designed to clinically evaluate the sealing ability and retention of the self-etching sealant compared to the conventional resin sealant. The aim was to evaluate and compare the retention and marginal integrity of the self-etch and acid etch sealant materials at three, six and twelve-month follow up. Methods: The study was designed as a double blinded, split mouth randomized controlled trial, . In total, 35 children (70 teeth) between 7 and 10 years of age formed part of the study. Group 1 received acid-etch sealant and Group 2 received self-etch sealants. The study participants and the investigator who performed the statistical analysis were blinded to the treatment allocation. All the samples were evaluated at 3, 6, and 12 months. The inter-group and intragroup comparison were carried out using the Chi-Square test and Friedman test with level of significance set at 5% and the P value less than 0.05. Results: Complete retention of sealants was observed in 34.5% of conventional acid etch (group 1) and 22.9% of self-etch samples (group 2) whereas complete loss of sealants were seen in 11.4% of group 1 and 20% of the group 2 samples and intergroup comparison of retention failure was non-significant (p=0.135). In total, 85.7% of the group 1 and 82.9% of the group 2 samples exhibited good marginal integrity with no clinical changes in the enamel around the margins but this was not statistically significant (p=0.5). Conclusions: Sealants with fewer procedural steps and those which provide adequate retention would be ideal for use in children. Thus, self-etch sealants have been found to be effective and efficient as a sealant in the present in-vivo study. Clinical Trials Registry, India registration: CTRI/2019/03/018343 (29/03/2019)., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Gupta D et al.)

Background: Self-etching has been shown to be beneficial compared to the other resin sealants especially in pediatric practice. The present in-vivo study was designed to clinically evaluate the sealing ability and retention of the self-etching sealant compared to the conventional resin sealant. The aim was to evaluate and compare the retention and marginal integrity of the self-etch and acid etch sealant materials at three, six and twelve-month follow up. Methods: This was designed a randomized controlled trial, with double blind parallel, split-mouth design. In total, 35 children (70 teeth) between 7 and 10 years of age formed part of the study. Group 1 received acid-etch sealant and Group 2 received self-etch sealants. The study participants and the investigator who performed the statistical analysis were blinded to the treatment allocation. All the samples were evaluated at 3, 6, and 12 months. The inter-group and intragroup comparison were carried out using the Chi-Square test and Friedman test with level of significance set at 5% and the P value less than 0.05. Results: Complete retention of sealants was observed in 34.5% of conventional acid etch (group 1) and 22.9% of self-etch samples (group 2) whereas complete loss of sealants were seen in 11.4% of group 1 and 20% of the group 2 samples and intergroup comparison of retention failure was non-significant (p=0.135). In total, 85.7% of the group 1 and 82.9% of the group 2 samples exhibited good marginal integrity with no clinical changes in the enamel around the margins but this was not statistically significant (p=0.5). Conclusions: Sealants with fewer procedural steps and those which provide adequate retention would be ideal for use in children. Thus, self-etch sealants have been found to be effective and efficient as a sealant in the present in-vivo study. Clinical Trials Registry, India registration: CTRI/2019/03/018343 (29/03/2019)., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Gupta D et al.)

IRM has been shown to be superior to conventional ZnOE cements. This study is a biotechnical investigation of IRM's effect on the dental pulp with respect to its sealing capacity. Enamel-dentin test bodies with IRM fillings were used in the in vitro part, where insufficiencies in sealing were detected with compressed air. The in vivo part included 44 buccal cavities in intact premolars. In teeth in which the material effect of IRM was tested, the IRM fillings were sealed off from the saliva by acid etch and composite resin. The observation intervals were 1, 7 and 28 days. Histologic changes such as capillary dilatations and presence of inflammatory cells in the pulp adjacent to the dentinal tubules involved in the cavity preparation were registered. The in vitro test showed no leakage in five cases out of six. After extreme temperature cycling, the leakage was comparable with that of zinc-containing amalgam of traditional alloy. The pulpal changes were mild and mainly ascribed to the material effect of IRM, since no evidence was found of leakage of biologic importance. [ABSTRACT FROM AUTHOR]

Endodontically treated premolars were restored using 5 different methods. Copper rings were filled with commercial hard-setting cement and the teeth were placed into the cement up to the level of tile cemento-enamel junction. The teeth were grouped according to restorative method, mounted in an Instron TT machine and the buccal walls subjected to a slowly increasing compressive force until fracture occurred. The force of fracture of the walls of each tooth was recorded and the results in the various groups compared. All teeth fractured in a similar manner irrespective of the restorative method used. The resistance to fracture of the teeth increased significantly when MOD cavities in the teeth were acid etched prior to the restoration with a composite resin. The use of a bonding agent after acid etching did not further increase the resistance to fracture of the premolars restored with a resin. The acid etch composite resin technique was as effective in preventing fractures of the teeth when 2 mm of the resin was removed and replaced with an amalgam as when the entire cavities were filled with the resin material. [ABSTRACT FROM AUTHOR]

Endodontic treatment with subsequent restoration of 3 immature incisors with horizontal fractures in the cervical region is described. In I tooth the fracture occurred supragingivally, whereas in 2 others the fracture was such that the root margins were between 1 and 2 mm subosseous. In these teeth proper access to the roots was established by means of orthodontic extrusion and/or periodontal surgery. After endodontic treatment, the gutta-percha was removed from the root canals to a level 2 to 3 mm apically to the osseous crest. The root canal dentin was acid-etched and a post to retain a crown was cemented into the canal with a composite resin. The resin will then penetrate into the dentinal tubules of the root canal walls and strengthen the root to such a degree that it becomes restorable. Semipermanent composite resin crowns and, in one instance, a more permanent porcelain crown were used to restore the teeth. [ABSTRACT FROM AUTHOR]

Endodontically treated teeth were restored by 8 different methods. Copper rings were filled with commercial hard setting cement and the teeth were placed into the cement to the level of the cemento-enamel junction. The teeth were grouped according to restorative methods, mounted in an Instron T.T. machine and subjected to a slowly increasing compressive force until fracture occurred. The force of fracture for each tooth was recorded and the results in the various groups compared. All teeth fractured in a similar manner, irrespective of restorative method used. Preparation of a post space in the roots significantly weakened the teeth. Cementation of a steel parapost with zinc oxyphosphate cement did not significantly strengthen the teeth. Filling the post space and the access cavity with a composite resin following acid etching of the root canal and cavity walls strengthened the teeth more than other methods used to restore them. This finding may be of clinical importance, for instance in the restoration of endodontically treated young teeth with incomplete root formation and wide root canals. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of this study was to compare, in vitro, the shear bond strength of resin-modified glass ionomer (RMGI) bonded to an enamel surface prepared by either sandblasting with 50μm of aluminium oxide particles, deproteinization with 5.25% NaOCl, or by combining both techniques., Material and Methods: One hundred and fifty human premolars were cleaned and randomly divided into five groups. In group 1, the teeth were etched using 37% phosphoric acid and bonded with Transbond XT. In group 2, the teeth were etched using 37% phosphoric acid and bonded with Fuji Ortho LC. In group 3, the teeth were deproteinized with 5.25% NaOCl for one minute then etched with 37% phosphoric acid and bonded with Fuji Ortho LC. In group 4, the enamel was sandblasted with 50μm of aluminium oxide particles for 5seconds prior to etching and bonding with Fuji Ortho LC. In group 5, the teeth were both sandblasted with 50μm of aluminium oxide particles for 5seconds and deproteinized with 5.25% NaOCl for one minute prior to etching using 37% phosphoric acid and bonding with Fuji Ortho LC. The shear bond strength was tested using a universal testing machine with a crosshead speed of 1.0mm/min. The adhesive remnant index (ARI) index was also determined for each group., Results: The mean shear bond strengths were as follows: group 1: 11.33±2.60MPa, group 2: 8.14±2.09, group 3: 9.57±3.25MPa, group 4: 9.49±1.99MPa and group 5: 9.76±2.29MPa (P=0.0001)., Conclusion: The results show that pre-treating the enamel with either sandblasting, NaOCl, or both, could give a significantly higher shear bond strength than using RMGI with acid etch alone., (Copyright © 2017 CEO. Published by Elsevier Masson SAS. All rights reserved.)