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Numerous systematic reviews (SRs) have produced conflicting findings on engine‐driven nickel–titanium reciprocating instruments (reciprocating instruments) since Yared's seminal study 15 years ago. This umbrella review analysed SRs examining the clinical and laboratory evidence regarding reciprocating instruments for root canal treatment. SRs that evaluated qualitatively and/or quantitatively the outcomes postoperative pain, oral health‐related quality of life (OHRQoL), shaping ability, debris extrusion, microbial load, endotoxins reduction, cyclic fatigue, file fracture, dentinal cracks and root canal filling removal were included. The AMSTAR 2 tool was used to evaluate SRs quality, while the ROBIS tool to assess risk of bias (RoB). Forty SRs were included. The SRs revealed predominantly 'high' RoB and 'critically low' quality. Most focused on technical outcomes, exhibiting significant methodological and statistical heterogeneity. Findings suggest comparable efficacy between reciprocating and rotary instruments. However, due to the scarcity of high‐quality evidence, future well‐designed studies and reviews considering core outcome measures are needed. [ABSTRACT FROM AUTHOR]

Purpose: To provide an overview of the in-vitro bond strength of universal adhesives to zirconia and analyze whether these adhesives are a reliable alternative to conventional zirconia primers. Materials and Methods: A systematic search was conducted in PubMed/Medline, Scopus, and ISI Web of Science databases up to August 2021. Investigations published in English, assessing resin-mediated bond to zirconia using universal adhesives compared to phosphate/silane-based primer or phosphate-based primer were included. After study selection and data extraction, risk of bias analysis was performed. Statistical analyses were performed using RevMan 5.4, with a random effects model, at a significance level of 0.05. Results: In total, 23 studies were included for qualitative and quantitative analysis. Universal adhesives showed higher bond strengths than did phosphate-based primers (p < 0.00001) to aged zirconia without airborne alumina-particle abrasion. Similar results were observed when the zirconia surface was airborne-particle abraded at baseline and after dynamic aging (p < 0.0001). When universal adhesives and phosphate-silane based primers were compared, similar bond strengths (p ≥ 0.001) were observed after surface abrasion, regardless of storage condition. Conclusion: The results showed that universal adhesives generate higher bond strengths when compared to conventional zirconia primers. [ABSTRACT FROM AUTHOR]

In this study, we investigate the antibacterial effect of silver atoms implanted into a thin surface layer of titanium at low energies using an alternative ion plating technology called Diversified Ion Plating. Silver atoms were incorporated into titanium samples using reactive low-voltage ion plating at 2 keV and 4 keV. Surface modifications and morphology were evaluated using wettability, profilometry measurements, and energy-dispersive spectroscopy. For a precise determination of the quantity and depth of implanted silver atoms on titanium surfaces, a combination of experimental techniques such as Rutherford Backscattering Spectrometry along with Monte Carlo simulations were utilized. To assess the antibacterial effects of the silver atoms incorporated into pure titanium surfaces, bacterial suspension immersion tests were performed with a standard strain of Staphylococcus aureus (ATCC 12600). The outcomes indicate that titanium surfaces implanted with silver atoms were more effective in inhibiting the growth of Staphylococcus aureus than pure titanium surfaces. Better results were found when the deposition was performed at 4 keV, indicating that a deeper implantation of silver, spanning a few nanometers, can result in a longer and more effective release of silver atoms. These findings suggest the potential for the development of new, cost-effective biomaterials, paving the way for improved implant materials in various health-related applications. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review and meta‐analysis aimed to evaluate the difference in the color stability of light‐cured and dual‐cured resin cements. Materials and Methods: Two separate reviewers used the PubMed, Scopus, Web of Science, Embase, and Scielo databases to execute the systematic review. For the analysis, studies that evaluated the color stability of dual‐cured and light‐cured resin cements over time were used. The random effects model was used in the meta‐analysis. Analyses of subgroups were carried out based on the aging technique. The methodological quality of each in vitro study was evaluated in accordance with the parameters of a prior systematic review. Results: From all databases, a total of 2223 articles were retrieved. Following the screening of titles and abstracts, 44 studies were selected for full text review, and a total of 27 articles were used for the qualitative analysis. Finally, 23 articles remained for the qualitative analysis. The majority of studies were labeled as having a medium risk of bias. The global analysis showed that the dual‐cure resin cements had considerably greater differences in the color change (p = 0.006). A high heterogeneity index (86%) was found in the analysis. Conclusions: The best available in vitro evidence suggests that dual‐polymerizing cement has higher color variation than light‐polymerized materials. To reduce the likelihood of color change after the luting of thin ceramic restorations, clinicians should employ light‐polymerizable resin cements. [ABSTRACT FROM AUTHOR]

Keywords: Nanocellulose; biological pretreatment; cellulase; eucalyptus; ; ; ; EN Nanocellulose biological pretreatment cellulase eucalyptus ZH 9363 9372 10 11/21/22 20221220 NES 221220 Introduction The global demand for cellulose nanofibers (CNF) and other cellulosic nanomaterials overcame 10,000 tons in 2018 and this demand is expected to increase to more than 70,000 tons by 2030 (Santmarti, Tammelin, and Lee [33]). In the present study, CNF were extracted from a bleached hardwood pulp using enzymatic hydrolysis as a pretreatment for subsequent mechanical fibrillation. In a comparison between unhydrolyzed pulps, that bleached pulp presented a higher crystallinity index than the unbleached one, which indicates that the bleaching sequence applied by our supplier partly removed some amorphous components, like hemicelluloses and lignin (De Campos et al. [10]). In general, compared to the unhydrolyzed CNF, it is clear that the CNF extracted from the unbleached pulp presented smaller decreases in diameter (around 75%) than those from bleached pulp, which showed decreases of almost 65%. [Extracted from the article]

Flexible and wearable electrochemical biosensors are considered a non-invasive tool for monitoring biological substances, thus attracting attention due to the simple assembly, fast response, ultra-sensitivity, and low cost. Among the substances detected by electrochemical methods, ascorbic acid (AA) stands out, as its presence in the body promotes adequate physiological functions of the immune, central nervous, and circulatory systems, thus preventing and treating various diseases. Herein, this work focuses on the use of nanostructured NdNiO3 compounds in an alternative flexible biosensor for AA detection by electrochemical sensing. Here, 1D nanostructures of NdNiO3 were obtained by wet pore filling of a mesoporous aluminum oxide template. To the best of our knowledge, no electrochemical biosensors using NdNiO3 nanotubes supported onto GO flexible electrodes have been reported for AA or other bioanalyte detection. Next, an electrochemical biosensor for AA was built using a laser-induced graphene (GO) electrode and two different NdNiO3 (NNO) nanotubes, one with an external diameter of 20 nm (NNO20) and the other with 100 nm (NNO100). The size effect and Ni3+/Ni2+ ratio influence on the sensing properties can be verified through electrochemical characterization. The GO/NNO20 and GO/NNO100 biosensors presented a detection range of 30 to 1100 μmol L-1, but the minimum detectable limit (3.8 μmol L-1) and sensitivity (0.031 μA μM-1 cm-2) are significantly better for the GO/NNO100 device. These outstanding results make both devices competitive with other AA devices listed in the literature. We also simulated the biosensors' real application and verified that these biosensors could detect AA in synthetic sweat and under application of mechanical deformations. Thus, the GO/NNO biosensors showed a promising alternative to the development of real-time monitoring, POC devices, and flexible wearable electrochemical devices to use in AA detection. Future works should address the potential to detect other bioanalytes. [ABSTRACT FROM AUTHOR]

To evaluate the ability of different esthetic archwires to retain oral biofilms in vitro. Seven different brands of coated orthodontic archwires were tested: two epoxy coated, two polytetrafluoroethylene coated, two rhodium coated, and one silver plus polymer coated. Conventional uncoated metallic archwires were used as controls. Streptococus mutans adherence to archwires was quantified by colony count following 24 hours of biolfilm growth, and total wire-associated biofilm was measured using a crystal violet staining assay. For both tests, two conditions were used: 0% sucrose and 3% sucrose. For statistical analysis, P <.05 was considered as statistically significant. For S. mutans colony forming units per biofilm, there were no statistically significant differences among the various archwires (P =.795 for 0% sucrose; P =.905 for 3% sucrose). Regarding total biofilm formed on archwires in the 3% sucrose condition, there were statistically significant differences in crystal violet staining only for the comparison between Niti Micro Dental White and Copper Ni-Ti wires (P <.05). The clinical use of esthetic-coated orthodontic wires may be considered to have similar risks as uncoated archwires for biofilm retention. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the whiteness index (WID) and surface roughness (Ra) of bovine enamel after simulated tooth brushing with different commercial and experimental whitening dentifrices. Materials and Methods: Cylindrical enamel bovine specimens were acid etched, stained, and divided in nine groups (n = 8): Colgate® Optic White®, Crest® Baking Soda and Peroxide, Arm and Hammer® Advanced White™ Extreme Whitening, Rembrandt® Deeply White® + Peroxide, Close up® White Attraction Natural Glow, Hinode Prowhite, and experimental dentifrice containing papain (PP), bromelain (PB), or papain and bromelain (PPB). Ra and WID were obtained initially and after 600, 1200, and 3,600 cycles of simulated tooth brushing. Data were analyzed using two‐way analysis of variance test (α = 0.05). Results: Ra was significantly influenced by both dentifrice (p = 0.043) and period of tooth‐brushing simulation (p < 0.001). Except for PP and PPB, all groups showed a statistically significant increase in Ra after simulated tooth brushing. After staining and brushing, none of the materials tested increased the initial WID. Conclusions: The effect of commercial whitening dentifrices may be related to their high abrasiveness. Experimental formulations tested provided a similar effect without undesired wear of enamel. Whitening dentifrices only act through an abrasive effect rather than bleaching the tooth structures. When used, special care must be taken for avoid undesired wear of enamel. Experimental dentifrices provided similar removal of extrinsic stains without undesired abrasiveness; however, this effect may be due to the use of less aggressive abrasives in their formulations. [ABSTRACT FROM AUTHOR]

This study investigated the impact of 'storage condition' and 'period of storage' on selected physico-mechanical properties and fracture reliability of a resin-based composite (RBC). Specimens, prepared from a nanofilled RBC (Filtek Z350 XT; 3M ESPE), underwent tests for degree of conversion (DC), flexural strength (σ), flexural modulus (E), and hardness. The specimens were initially grouped into dry storage at 37°C or wet storage in distilled water at 37°C. Subsequently, they were further divided into four subgroups based on the period of storage: 6, 24, 72, or 168 hours. Specimens tested immediately after preparation served as control. Data analysis employed two-way ANOVA and Weibull analysis (α = 5%). Compared to the control, an increase in DC was observed only after 72 hours of dry storage; σ showed higher values after both dry and wet storage, regardless of the storage period (except for the group wet-stored for 168 hours); E increased with dry storage for at least 24 hours or wet storage for 72 hours; and hardness increased after dry storage for at least 24 hours or wet storage for up to 72 hours. The Weibull modulus remained unchanged under any of the distinct storage conditions. Dry storage resulted in greater characteristic strength than the control, whereas wet storage contributed to higher strength values only at shorter periods (up to 24 hours). Overall, the inherent properties of RBCs with a similar composition to that tested in this study may change with varying storage conditions and periods.

Purpose: To provide an overview of the in-vitro bond strength of universal adhesives to zirconia and analyze whether these adhesives are a reliable alternative to conventional zirconia primers., Materials and Methods: A systematic search was conducted in PubMed/Medline, Scopus, and ISI Web of Science databases up to August 2021. Investigations published in English, assessing resin-mediated bond to zirconia using universal adhesives compared to phosphate/silane-based primer or phosphate-based primer were included. After study selection and data extraction, risk of bias analysis was performed. Statistical analyses were performed using RevMan 5.4, with a random effects model, at a significance level of 0.05., Results: In total, 23 studies were included for qualitative and quantitative analysis. Universal adhesives showed higher bond strengths than did phosphate-based primers (p < 0.00001) to aged zirconia without airborne alumina-particle abrasion. Similar results were observed when the zirconia surface was airborne-particle abraded at baseline and after dynamic aging (p < 0.0001). When universal adhesives and phosphate-silane based primers were compared, similar bond strengths (p ≥ 0.001) were observed after surface abrasion, regardless of storage condition., Conclusion: The results showed that universal adhesives generate higher bond strengths when compared to conventional zirconia primers.