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The field of tissue engineering has witnessed significant advancements in recent years, driven by the pursuit of innovative solutions to address the challenges of bone regeneration. In this study, we developed an electrospun composite scaffold for bone tissue engineering. The composite scaffold is made of a blend of poly(L‐lactide‐co‐ε‐caprolactone) (PLCL) and polyethylene glycol (PEG), with the incorporation of calcined and lyophilized silicate‐chlorinated bioactive glass (BG) particles. Our investigation involved a comprehensive characterization of the scaffold's physical, chemical, and mechanical properties, alongside an evaluation of its biological efficacy employing alveolar bone‐derived mesenchymal stem cells. The incorporation of PEG and BG resulted in elevated swelling ratios, consequently enhancing hydrophilicity. Thermal gravimetric analysis confirmed the efficient incorporation of BG, with the scaffolds demonstrating thermal stability up to 250°C. Mechanical testing revealed enhanced tensile strength and Young's modulus in the presence of BG; however, the elongation at break decreased. Cell viability assays demonstrated improved cytocompatibility, especially in the PLCL/PEG+BG group. Alizarin red staining indicated enhanced osteoinductive potential, and fluorescence analysis confirmed increased cell adhesion in the PLCL/PEG+BG group. Our findings suggest that the PLCL/PEG/BG composite scaffold holds promise as an advanced biomaterial for bone tissue engineering. [ABSTRACT FROM AUTHOR]

The evolutionary establishment of an internal biological clock is a primordial event tightly associated with a 24‐h period. Changes in the circadian rhythm can affect cellular functions, including proliferation, DNA repair and redox state. Even isolated organs, tissues and cells can maintain an autonomous circadian rhythm. These cell‐autonomous molecular mechanisms are driven by intracellular clock genes, such as BMAL1. Little is known about the role of core clock genes and epigenetic modifications in the skin. Our focus was to identify BMAL1‐driven epigenetic modifications associated with gene transcription by mapping the acetylation landscape of histones in epithelial cells responding to injury. We explored the role of BMAL1 in epidermal wound and tissue regeneration using a loss‐of‐function approach in vivo. We worked with BMAL1 knockout mice and a contraction‐resistance wound healing protocol, determining the histone modifications using specific antibodies to detect the acetylation levels of histones H3 and H4. We found significant differences in the acetylation levels of histones in both homeostatic and injured skin with deregulated BMAL1. The intact skin displayed varied acetylation levels of histones H3 and H4, including hyperacetylation of H3 Lys 9 (H3K9). The most pronounced changes were observed at the repair site, with notable alterations in the acetylation pattern of histone H4. These findings reveal the importance of histone modifications in response to injury and indicate that modulation of BMAL1 and its associated epigenetic events could be therapeutically harnessed to improve skin regeneration. [ABSTRACT FROM AUTHOR]

Background: The effects of ethylenediaminetetraacetic acid (EDTA) on regenerative endodontic procedures (REPs) are controversial, because, despite releasing growth factors from dentine, some studies show negative effects on cell behaviour. Objectives: The aim of the study was to investigate the influence of the use of EDTA in REP on the growth factors' release, cell behaviour and tissue regeneration. Methods: A systematic search was conducted (PubMed/Medline, Scopus, Cochrane Library, Web of Science, Embase, OpenGrey and reference lists) up to February 2021. Only in vivo and in vitro studies evaluating the effects of EDTA on the biological factors of dentine, pulp/periapical tissues and cell behaviour were eligible. Studies without a control group or available full text were excluded. The growth factors' release was the primary outcome. Risk of bias in the in vitro and in vivo studies was performed according to Joanna Briggs Institute's Checklist and SYRCLE's RoB tool, respectively. Results: Of the 1848 articles retrieved, 36 were selected. Amongst these, 32 were in vitro, three animal studies and one with both models. The EDTA concentrations ranged from 3% to 15%, at different times. Regarding growth factors' release (17 studies), 15 studies found significant transforming growth factor (TGF)‐β release after dentine conditioning with EDTA, and most found no influence on vascular endothelial growth factor release. Regarding cell behaviour (26 studies), eight studies showed no influence of EDTA‐treated dentine on cell viability, whereas, five, nine and six studies showed higher cell migration, adhesion and differentiation respectively. No influence of EDTA conditioning was observed in animal studies. In vitro studies had a low risk of bias, whereas animal studies had high risk of bias. Meta‐analysis was unfeasible. Discussion: This review found that EDTA increased TGF‐β release and improved cell activity. However, well‐designed histological analyses using immature teeth models are needed. Conclusions: High‐quality in vitro evidence suggests that EDTA‐treated dentine positively influences TGF‐β release, cell migration, attachment and differentiation; further research to evaluate its influence on tissue regeneration is necessary due to low methodological quality of the animal studies. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the following papers is to explore plausible alternative futures for dental education. The COVID‐19 pandemic, challenges emerging from racism in the US, and social unrest were the precipitating factors leading to this consideration of academic dentistry in approximately 5 years. Methods: In 2020–2021, five teams of six individual followed a seven‐step process to develop five different scenarios of dental education in 2026. Four of these scenarios are constructed by considering a range of uncertainties associated with economic sustainability and educational innovation. A fifth scenario describes the optimal case for dental education's role should another pandemic occur. Results: Each scenario is presented as a narrative in three parts: scenario highlights (summary), life in the scenario (fictional case), and scenario details (a description of significant factors within the envisioned future of the scenario). As a strategic tool, these scenarios will assist leaders, institutions, and stakeholders to anticipate and prepare for different futures, identify key indicators that a particular future is emerging, and guide decision‐making to create the most desirable future in a changing environment. Conclusion: Institutions are encouraged to incorporate these scenarios into their strategic and contingency planning efforts and to use them to generate dialogue during faculty development initiatives. This study provides institutions with a process and model they can follow to create scenarios at the institutional level. The final paper in this collection is a guide that provides ideas and instructions for using the scenarios in curricular and extracurricular activities with faculty members and students. [ABSTRACT FROM AUTHOR]

This study evaluated the biocompatibility of degradable polydioxanone (PDS) electrospun drug delivery systems (hereafter referred as matrices) containing metronidazole (MET) or ciprofloxacin (CIP) after subcutaneous implantation in rats. Sixty adult male rats were randomized into six groups: SHAM (sham surgery); PDS (antibiotic‐free matrix); 1MET (one 25 wt% MET matrix); 1CIP (one 25 wt% CIP matrix); 2MET (two 25 wt% MET matrices); and 2CIP (two 25 wt% CIP matrices). At 3 and 30 days, animals were assessed for inflammatory cell response (ICR), collagen fibers degradation, and oxidative profile (reactive oxygen species [ROS]; lipid peroxidation [LP]; and protein carbonyl [PC]). At 3 days, percentages of no/discrete ICR were 100, 93.3, 86.7, 76.7, 50, and 66.6 for SHAM, PDS, 1MET, 1CIP, 2MET, and 2CIP, respectively. At 30 days, percentages of no/discrete ICR were 100% for SHAM, PDS, 1MET, and 1CIP and 93.3% for 2MET and 2CIP. Between 3 and 30 days, SHAM, 1CIP, and 2CIP produced collagen, while 1MET and 2MET were unchanged. At 30 days, the collagen fiber means percentages for SHAM, PDS, 1MET, 1CIP, 2MET, and 2CIP were 63.7, 60.7, 56.6, 62.6, 51.8, and 61.7, respectively. Antibiotic‐eluting matrices showed similar or better oxidative behavior when compared to PDS, except for CIP‐eluting matrices, which showed higher levels of PC compared to SHAM or PDS at 30 days. Collectively, our findings indicate that antibiotic‐eluting matrices may be an attractive biocompatible drug delivery system to fight periodontopathogens. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B, 2019. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the fatigue failure load of distinct lithium disilicate restoration designs cemented on a chairside titanium base for maxillary anterior implant‐supported restorations. Materials and Methods: A left‐maxillary incisor restoration was virtually designed and sorted into 3 groups: (n = 10/group; CTD: lithium disilicate crowns cemented on custom‐milled titanium abutments; VMLD: monolithic full‐contour lithium disilicate crowns cemented on a chairside titanium‐base; VCLD: lithium disilicate crowns bonded to lithium disilicate customized anatomic structures and then cemented onto a chairside titanium base). The chairside titanium base was air‐abraded with aluminum oxide particles. Subsequently, the titanium base was steam‐cleaned and air‐dried. Then a thin coat of a silane agent was applied. The intaglio surface of the ceramic components was treated with 5% hydrofluoric acid (HF) etching gel, followed by silanization, and bonded with a resin cement. The specimens were fatigued at 20 Hz, starting with a 100 N load (5000× load pulses), followed by stepwise loading from 400 N up to 1400 N (200 N increments) at a maximum of 30,000 cycles each. The failure loads, number of cycles, and fracture analysis were recorded. The data were statistically analyzed using one‐way ANOVA, followed by pairwise comparisons (p < 0.05). Kaplan‐Meier survival plots and Weibull survival analyses were reported. Results: For catastrophic fatigue failure load and the total number of cycles for failure, VMLD (1260 N, 175,231 cycles) was significantly higher than VCLD (1080 N, 139,965 cycles) and CDT (1000 N, 133,185 cycles). VMLD had a higher Weibull modulus demonstrating greater structural reliability. Conclusion: VMLD had the best fatigue failure resistance when compared with the other two groups. [ABSTRACT FROM AUTHOR]

Evoked bleeding (EB) clinical procedure, comprising a disinfection step followed by periapical tissue laceration to induce the ingrowth of undifferentiated stem cells from the periodontal ligament and alveolar bone, is currently the only regenerative‐based therapeutic approach to treating pulp tissue necrosis in undeveloped (immature) permanent teeth approved in the United States. Yet, the disinfection step using antibiotic‐based pastes leads to cytotoxic, warranting a biocompatible strategy to promote root canal disinfection with no or minimal side‐effects to maximize the regenerative outcomes. The purpose of this investigation was to develop a tubular three‐dimensional (3D) triple antibiotic‐eluting construct for intracanal drug delivery. Morphological (scanning electron microscopy), chemical (Fourier transform infrared spectroscopy), and mechanical (tensile testing) characteristics of the polydioxanone‐based triple antibiotic‐eluting fibers were assessed. The antimicrobial properties of the tubular 3D constructs were determined in vitro and in vivo using an infected (Actinomyces naeslundii) dentin tooth slice model and a canine method of periapical disease, respectively. The in vitro data indicated significant antimicrobial activity and the ability to eliminate bacterial biofilm inside dentinal tubules. In vivo histological findings demonstrated that, using the EB procedure, the tubular 3D triple antibiotic‐eluting construct allowed the formation of an appropriate environment that led to apex closure and the ingrowth of a thin layer of osteodentin‐like tissue into the root canal. Taken together, these findings indicate that our novel drug delivery construct is a promising biocompatible disinfection strategy for immature permanent teeth with necrotic pulps. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1576–1586, 2019. [ABSTRACT FROM AUTHOR]

A commercially available three‐step (etch‐and‐rinse) adhesive was modified by adding chlorhexidine (CHX)‐loaded nanotubes (Halloysite®, HNT) at two concentrations (CHX10% and CHX20%). The experimental groups were: SBMP (unmodified adhesive, control), HNT (SBMP modified with HNT), CHX10 (SBMP modified with HNT loaded with CHX10%), and CHX20 (SBMP modified with HNT loaded with CHX20%). Changes in the degree of conversion (DC%), Knoop hardness (KHN), water sorption (WS), solubility (SL), antimicrobial activity, cytotoxicity, and anti‐matrix metalloproteinase [MMP‐1] activity (collagenase‐I) were evaluated. In regards to DC%, two‐way ANOVA followed by Tukey's post‐hoc test revealed that only the factor "adhesive" was statistically significant (p < 0.05). No significant differences were detected in DC% when 20 s light‐curing was used (p > 0.05). For Knoop microhardness, one‐way ANOVA followed by the Tukey's test showed statistically significant differences when comparing HNT (20.82 ± 1.65) and CHX20% (21.71 ± 2.83) with the SBMP and CHX10% groups. All adhesives presented similar WS and cytocompatibility. The CHX‐loaded nanotube‐modified adhesive released enough CHX to inhibit the growth of S. mutans and L. casei. Adhesive eluates were not able to effectively inhibit MMP‐1 activity. The evaluation of higher CHX concentrations might be necessary to provide an effective and predictable MMP inhibition. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res B Part B, 2018. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 868–875, 2019. [ABSTRACT FROM AUTHOR]

This study investigated the antimicrobial and osteogenic properties of titanium (Ti) disks superficially modified with tetracycline (TCH)-incorporated polymer nanofibers. The experiments were carried out in two phases. The first phase dealt with the synthesis and characterization (i.e., morphology, mechanical strength, drug release, antimicrobial activity, and cytocompatibility) of TCH-incorporated fibers. The second phase was dedicated to evaluating both the antimicrobial and murine-derived osteoprecursor cell (MC3T3-E1) response of Ti-modified with TCH-incorporated fibers. TCH was successfully incorporated into the submicron-sized and cytocompatible fibers. All TCH-incorporated mats presented significant antimicrobial activity against periodontal pathogens. The antimicrobial potential of the TCH-incorporated fibers-modified Ti was influenced by both the TCH concentration and bacteria tested. At days 5 and 7, a significant increase in MC3T3-E1 cell number was observed for TCH-incorporated nanofibers-modified Ti disks when compared to that of TCH-free nanofibers-modified Ti-disks and bare Ti. A significant increase in alkaline phosphatase (ALP) levels on the Ti disks modified with TCH-incorporated nanofiber on days 7 and 14 was seen, suggesting that the proposed surface promotes early osteogenic differentiation. Collectively, the data suggest that TCH-incorporated nanofibers could function as an antimicrobial surface modifier and osteogenic inducer for Ti dental implants. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2085-2092, 2017. [ABSTRACT FROM AUTHOR]

Purpose To evaluate the effects of simulated gastric juice on CAD/CAM resin composites by means of morphological and mechanical (i.e., hardness) evaluations. Materials and Methods Fourteen specimens of each resin composite (Lava Ultimate and Paradigm MZ100) were prepared according to the manufacturer's instructions. They were submitted to erosive challenges in a simulated gastric juice (pH = 1.2) solution for 6 and 24 hours. Vickers microhardness and surface roughness (Ra, Rq) evaluations were taken before (baseline) and after acid exposure. Morphological analysis was obtained using scanning electron microscopy (SEM). Statistical analysis was performed using two-way repeated measures ANOVA and Student-Newman-Keuls's test (α = 0.05). Results Paradigm MZ100 demonstrated higher microhardness than Lava Ultimate regardless of the storage time period ( p ≤ 0.001), and microhardness was not affected by the acidic challenge ( p = 0.58). After 6 hours of acid exposure, a significant decrease in Ra and Rq was seen for Paradigm MZ100 when compared to the baseline (Ra p = 0.032; Rq p = 0.013); however, for Lava Ultimate only Rq decreased ( p = 0.021), while Ra remained unchanged ( p = 0.38). After 24 hours of acid exposure, while Paradigm MZ100 exhibited no additional changes in surface roughness ( p ≥ 0.75), Lava Ultimate became rougher (Ra p = 0.041; Rq p = 0.014), as confirmed by SEM imaging. Conclusions The acidic scenario tested in the present study changed the surface roughness of the resin composites but not their Vickers microhardness. Moreover, both resin composites seem suitable for use under acidic scenarios, although Paradigm MZ100 showed enhanced stability compared to Lava Ultimate. [ABSTRACT FROM AUTHOR]

This study examined the effects of distinct hydrofluoric acid concentrations on the mechanical behavior of a lithium disilicate-based glass ceramic. Bar-shaped specimens were produced from ceramic blocks (e.max CAD, Ivoclar Vivadent). The specimens were polished, chamfered, and sonically cleaned in distilled water. The specimens were randomly divided into five groups ( n = 23). The HF1, HF3, HF5, and HF10 specimens were etched for 20 s with acid concentrations of 1%, 3%, 5%, and 10%, respectively, while the SC (control) sample was untreated. The etched surfaces were evaluated using a scanning electron microscope and an atomic force microscope. Finally, the roughness was measured, and 3-point bending flexural tests were performed. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey's test ( α = 0.05). The Weibull modulus and characteristic strength were also determined. No statistical difference in the roughness and flexural strength was determined among the groups. The structural reliabilities (Weilbull moduli) were similar for the tested groups; however, the characteristic strength of the HF1 specimen was greater than that of the HF10 specimen. Compared with the untreated ceramic, the surface roughness and flexural strength of the ceramic were unaffected upon etching, regardless of the acid concentration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 885-891, 2017. [ABSTRACT FROM AUTHOR]

Purpose Glass fibers were introduced to increase the fracture resistance of resin-based composites restorations; however, the poor polymerization between fibers and resin-based composite were sometimes noted and can cause debonding and failure. The purpose of this study was to investigate the effects of different polymerization methods as well as fiber types on the mechanical behavior of fiber-reinforced resin-based composites. Materials and Methods Seventy-five specimens were fabricated and divided into one control group and four experimental groups (n = 15), according to the type of glass fiber (strip or mesh) and polymerization methods (one- or two-step). A 0.2-mm-thick fiber layer was fabricated with different polymerization methods, on top of which a 1.8 mm resin-based composite layer was added to make a bar-shape specimen, followed by a final polymerization. Specimens were tested for flexural strength and flexural modulus. The failure modes of specimens were observed by scanning electron microscopy. Results The fiber types showed significant effect on the flexural strength of test specimens (F = 469.48, p < 0.05), but the polymerization methods had no significant effect (F = 0.05, p = 0.82). The interaction between these two variables was not significant (F = 1.73, p = 0.19). In addition, both fiber type (F = 9.71, p < 0.05) and polymerization method (F = 12.17, p < 0.05) affected the flexural modulus of test specimens; however, the interaction between these two variables was not significant (F = 0.40, p = 0.53). Conclusions The strip fibers showed better mechanical behavior than mesh fibers and were suggested for resin-based composites restorations reinforcement; however, different polymerization methods did not have a significant effect on the strength and failure mode of fiber-reinforced resin-based composites. [ABSTRACT FROM AUTHOR]

Purpose To determine the best method of cleaning saliva-contaminated zirconia in preparation for resin bonding. Material and Methods Flat blocks of zirconia were particle abraded with aluminum oxide and divided into eight groups (n = 10). Groups 1 to 4 were first treated with one coat of an MDP primer (Z-prime Plus) and groups 5 to 8 were left untreated. A thin coat of fresh whole saliva was painted on all specimens (except the control, group 1) and left in contact for 3 minutes. The specimens were then cleaned by rinsing with water for 20 seconds (groups 2 and 5), or cleaned with 35% phosphoric acid for 20 seconds and rinsed (groups 3 and 6), or cleaned with a zirconia cleaning solution (Ivoclean) for 20 seconds and rinsed (groups 4 and 7), or abraded with aluminum oxide particles and rinsed (group 5). Following the cleaning procedure, groups 5 to 8 were treated with one coat of Z-prime Plus. A 2.5 mm diameter tube was filled with composite (Z100), affixed to the zirconia surface, and light-cured. Specimens were stored in water (37°C for 24 hours) followed by thermocycling (5°C to 55°C for 10,000 cycles). Shear bond strength testing was performed at a crosshead speed of 1 mm/min. Bond strength values were compared to the control using a Dunnett's test (alpha = 0.05). Contact angles of the zirconia specimens with and without Z-prime Plus were measured with water using a goniometer. Results Groups 2, 5, and 8 were not significantly different from the control. Application of Z-prime made the zirconia surface more hydrophobic. Conclusions If salivary contamination occurs after MDP application, rinsing off the saliva with water will preserve bond strength. If salivary contamination occurs prior to MDP application, particle abrasion or cleaning with Ivoclean will preserve bond strength. [ABSTRACT FROM AUTHOR]

Composite fibrous electrospun membranes based on poly( dl-lactide) (PLA) and poly(ε-caprolactone) (PCL) were engineered to include borate bioactive glass (BBG) for the potential purposes of guided bone regeneration (GBR). The fibers were characterized using scanning and transmission electron microscopies, which respectively confirmed the submicron fibrous arrangement of the membranes and the successful incorporation of BBG particles. Selected mechanical properties of the membranes were evaluated using the suture pullout test. The addition of BBG at 10 wt % led to similar stiffness, but more importantly, it led to a significantly stronger (2.37 ± 0.51 N mm) membrane when compared with the commercially available Epiguide® (1.06 ± 0.24 N mm) under hydrated conditions. Stability (shrinkage) was determined after incubation in a phosphate buffer solution from 24 h up to 9 days. The dimensional stability of the PLA:PCL-based membranes with or without BBG incorporation (10.07-16.08%) was similar to that of Epiguide (14.28%). Cell proliferation assays demonstrated a higher rate of preosteoblasts proliferation on BBG-containing membranes (6.4-fold) over BBG-free membranes (4- to 5.8-fold) and EpiGuide (4.5-fold), following 7 days of in vitro culture. Collectively, our results demonstrated the ability to synthesize, via electrospinning, stable, polymer-based submicron fibrous BBG-containing membranes capable of sustaining osteoblastic attachment and proliferation-a promising attribute in GBR. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 594-605, 2016. [ABSTRACT FROM AUTHOR]

This study aimed to develop and evaluate resinbased experimental dental sealants containing electrospun nylon-6 (N6) and chitosan (CH) fibers in an attempt to improve the physicomechanical properties and provide an antibacterial protective effect, respectively. Electrospun N6 and CH mats were immersed into a resin mixture, lightcured, and then cryomilled to obtain micron-sized resinmodified fiber particles. Different levels of the novel cryomilled particles (i.e. 1, 2.5, and 5% relative to the resin mixture, % by weight) were used to prepare the N6- and CHcontaining sealants. A commercial sealant and the experimental resin mixture (unfilled) were used as controls. Flexural strength (FS), Vickers microhardness (VH), and agar diffusion tests were performed. The data were analyzed at the 5% significance level. No significant difference in fiber diameter of N6 (503 ± 31 nm) and CH (595 ± 38 nm) was observed. Upon cryomilling, the resin-modified CH and N6 mats led to the formation of irregularly-shaped particles, with an average diameter of 14.24 µm and 15.87 µm, respectively. CH-5% had significantly higher FS (115.3 ± 1.3 MPa) than all the other groups. CH-1% had significantly higher hardness values (38.3 ± 0.3 VHN) than all the other groups. Collectively, the results indicated that CH-containing sealants presented the highest FS and hardness; however, none of the CHcontaining sealants displayed antimicrobial properties. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study was to evaluate the influence of full-contour (Y-TZP) zirconia surface roughness (glazed vs. as-machined) on the wear behavior of glass-ceramics. Materials and Methods Thirty-two full contour Y-TZP (Diazir®) specimens (hereafter referred to as zirconia sliders) (ϕ = 2 mm, 1.5 mm in height) were fabricated using CAD/CAM and sintered according to the manufacturer's instructions. Zirconia sliders were embedded in brass holders using acrylic resin and then randomly assigned (n = 16) according to the surface treatment received, that is, as-machined or glazed. Glass-ceramic antagonists, Empress/EMP and e.max/EX, were cut into tabs (13 × 13 × 2 mm3), wet-finished, and similarly embedded in brass holders. Two-body pin-on-disk wear testing was performed at 1.2 Hz for 25,000 cycles under a 3 kg load. Noncontact profilometry was used to measure antagonist height (μm) and volume loss (mm3). Qualitative data of the zirconia testing surfaces and wear tracks were obtained using SEM. Statistics were performed using ANOVA with a significance level of 0.05. Results As-machined yielded significantly higher mean roughness values (Ra = 0.83 μm, Rq = 1.09 μm) than glazed zirconia (Ra = 0.53 μm, Rq = 0.78 μm). Regarding glass-ceramic antagonist loss, as-machined zirconia caused significantly less mean height and volume loss (68.4 μm, 7.6 mm3) for EMP than the glazed group (84.9 μm, 9.9 mm3), while no significant differences were found for EX. Moreover, EMP showed significantly lower mean height and volume loss than EX ( p < 0.0001). SEM revealed differences on wear characteristics between the glass-ceramics tested. Conclusion e.max wear was not affected by zirconia surface roughness; however, Empress wear was greater when opposing glazed zirconia. Overall, surface glazing on full-contour zirconia did not minimize glass-ceramic wear when compared with as-machined zirconia. [ABSTRACT FROM AUTHOR]

This investigation studied how the incorporation of a natural crosslinking agent, genipin (Gp), into the AlloDerm® (AD) rehydration protocol affects the biomechanical properties and the stability of the collagenous matrix. AD is a minimally processed, noncrosslinked, freeze‐dried collagen‐based graft. Samples were immersed in a saline solution for 5 min and then randomly assigned for further rehydration (30 min) into three groups, according to the crosslinking agent: G1‐control (saline), G2‐1 wt % genipin, and G3‐1 wt % glutaraldehyde. Gp crosslinking for a prolonged time of 6 h (G4) was also investigated. After washing (5 min), samples were mechanically tested wet in tension. G2 demonstrated a significantly higher ultimate tensile strength (UTS) and E relative to G1. However, G3 did not show a noteworthy increase in these properties. A significant enhancement in UTS was found when Gp exposure time was increased from 30 min to 6 h. FT‐IR revealed a protein backbone with no significant peak shifting for all samples due to crosslinking. However, a considerable decrease in ‐NH2 peak intensity occurred due to crosslinking reactions. Additionally, DSC analyses indicated an important shift in the denaturation temperature for crosslinked samples. SEM micrographs revealed no alterations in the native fibrous morphology after crosslinking. Simultaneous genipin incorporation during the rehydration protocol of AlloDerm significantly enhances its biomechanical properties. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010. [ABSTRACT FROM AUTHOR]

This article presents details of processing, characterization and in vitro as well as in vivo evaluations of powder metallurgy processed Ti‐13Nb‐13Zr samples with different levels of porosity. Sintered samples were characterized for density, crystalline phases (XRD), and microstructure (SEM and EDX). Samples sintered at 1000°C showed the highest porosity level (∼30%), featuring open and interconnected pores ranging from 50 to 100 μm in diameter but incomplete densification. In contrast, samples sintered at 1300 and 1500°C demonstrated high densification with 10% porosity level distributed in a homogeneous microstructure. The different sintering conditions used in this study demonstrated a coherent trend that is increase in temperature lead to higher sample densification, even though densification represents a drawback for bone ingrowth. Cytotoxicity tests did not reveal any toxic effects of the starting and processed materials on surviving cell percentage. After an 8‐week healing period in rabbit tibias, the implants were retrieved, processed for nondecalcified histological evaluation, and then assessed by backscattered electron images (BSEI‐SEM) and EDX. Bone growth into the microstructure was observed only in samples sintered at 1000°C. Overall, a close relation between newly formed bone and all processed samples was observed. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009 [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Discussion Conclusions Bibliometric analysis is a critical indicator of the influence and relevance of scientific papers, whilst also highlighting key contributors and gaps in knowledge in a scientific field.To update and analyse the 100 most‐cited papers in regenerative endodontics from 2019 to 2023.A search of the most‐cited recent papers focusing on regenerative endodontics using journals included in the category, ‘Dentistry, Oral Surgery & Medicine’, in the Clarivate Web of Science database from 2019 to 2023 was performed. Three researchers conducted the study selection and data extraction. Data extraction included publication title and year, authors, number and mean number of citations, institution, country and continent, study design, journal title, keywords and research topic. Citation counts were also collected in Google Scholar and Scopus databases. Graphical bibliometric networks were created using VOSviewer software.The number of citations of the 100 most‐cited articles ranged from 6 to 85. Most were published in 2020 (n = 48), principally in the Journal of Endodontics (47%), followed by International Endodontic Journal (13%), Journal of Dental Research (6%) and Dental Materials (6%). Laboratory study was the most common study design amongst the included papers (n = 47), followed by narrative reviews (n = 17) and observational studies (n = 16). The most frequent first author on the top three most‐cited papers was Hacer Aksel, whilst Adham A. Azim (n = 6; 89 citations) contributed most to the top 100 articles. The institution from which most articles originated was the University of Hong Kong (China) (n = 5; 81 citations), whereas the corresponding authors were predominantly from the United States of America (USA) (n = 31; 560 citations). The VOSviewer map of co‐authorship demonstrated research collaborative clusters. ‘Regenerative endodontics’ and ‘stem‐cells’ were the most employed keywords (37 and 36 occurrences respectively).The current study was designed not only to showcase the most influential papers in regenerative endodontics since 2019 but also to provide a better understanding of global research in this area over the last five years.This bibliometric analysis highlighted papers, authors, institutions and keywords in regenerative endodontics. The 100 most‐cited papers primarily consisted of laboratory studies published in the USA, focusing on evaluating biomaterials and scaffold design strategies in contact with stem cells. Clinical studies and systematic reviews representing higher levels of scientific evidence are currently not the most influential in the regenerative endodontic field. [ABSTRACT FROM AUTHOR]