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Celebrating the centenary of calcium hydroxide (CH), the aim of this study was to analyze the 100 most-cited papers on this biomaterial. The bibliometric analysis was conducted in the Web of Science Core Collection (WoS-CC) database. Title, authorship information, study design, year, journal, number of citations, CH use, and fields of Dentistry were extracted. The number of citations in the WoS-CC, Scopus, and Google Scholar databases was cross-matched with the Spearman correlation. From the 1,596 papers identified, a list was compiled with the 100 most-cited papers. The number of citations in WoS-CC ranged from 78 to 384 (mean: 131.4). The main CH uses were: intracanal dressing (61%), and pulp protection (29%). The fields of Dentistry with most studies on CH were Endodontics (62%) and Operative Dentistry (30%). The most frequent study design was laboratory studies (44%). Three hundred and thirty-five authors from 29 countries were identified. The United States of America (USA) was the leading country with 23 articles. Dag Ørstavik was the author with the most papers and citations (9 papers; 1,118 citations). Most papers were published between 1991 and 2015 and in the Journal of Endodontics (38%). A very strong positive correlation was observed among the number of citations in the databases. The 100 most-cited papers were published mainly by European journals or from USA, with laboratory and multifaceted interventional designs. The present study celebrated the centenary of CH, highlighting the role and importance of this biomaterial in Dentistry. Celebrando el centenario del hidróxido de calcio (HC), el objetivo de este estudio fue analizar los 100 artículos más citados sobre este biomaterial. Análisis bibliométrico se realizó en la base de datos Web of Science Core Collection (WoS-CC). Se extrajo título, información de autoría, diseño del estudio, año, revista, número de citas, uso de HC y áreas de la Odontología. Se cruzó número de citas en las bases de datos WoS-CC, Scopus y Google Scholar con la correlación de Spearman. De los 1.596 artículos identificados, se compiló una lista de los 100 artículos más citados. El número de citas en WoS-CC osciló entre 78 y 384 (media: 131,4). Los principales usos del HC fueron: medicación intracanal (61%) y protección pulpar (29%). Las áreas de la Odontología con más estudios sobre HC fueron Endodoncia (62%) y Odontología Restaurativa (30%). El diseño de estudio más frecuente fue el de laboratorio (44%). Se identificaron 335 autores de 29 países. Estados Unidos fue el país líder con 23 artículos. Dag Ørstavik fue el autor con más artículos y citas (9 artículos; 1118 citas). La mayoría de los artículos se publicaron entre 1991 y 2015 en el Journal of Endodontics (38%). Se observó una correlación positiva muy fuerte entre el número de citas en las bases de datos. Los 100 artículos más citados fueron publicados principalmente por revistas europeas o estadounidenses, con diseños de laboratorio e intervenciones multifacéticas. El presente estudio conmemoró el centenario del HC, destacando el papel y la importancia de este biomaterial dental. Celebrando o centenário do hidróxido de cálcio (HC), o objetivo desse estudo foi analisar os 100 artigos mais citados sobre esse biomaterial. A análise bibliométrica foi realizada na base de dados Web of Science Core Collection (WoS-CC). Título, informações sobre autoria, desenho do estudo, ano, periódico, número de citações, uso do HC e áreas da Odontologia foram extraídos. O número de citações nas bases de dados WoS-CC, Scopus e Google Scholar foi cruzado com a correlação de Spearman. Dos 1.596 artigos identificados, foi compilada uma lista com os 100 artigos mais citados. O número de citações no WoS-CC variou de 78 a 384 (média: 131,4). Os principais usos do HC foram: medicação intracanal (61%) e proteção pulpar (29%). As áreas da Odontologia com mais estudos sobre HC foram Endodontia (62%) e Dentística (30%). O desenho de estudo mais frequente foi laboratorial (44%). Trezentos e trinta e cinco autores de 29 países foram identificados. Os Estados Unidos da América (EUA) foram o país líder com 23 artigos. Dag Ørstavik foi o autor com mais artigos e citações (9 artigos; 1.118 citações). A maioria dos artigos foi publicada entre 1991 e 2015 e no Journal of Endodontics (38%). Foi observada uma correlação positiva muito forte entre o número de citações nas bases de dados. Os 100 artigos mais citados foram publicados principalmente por periódicos europeus ou dos EUA, com desenhos laboratoriais e de intervenções multifacetadas. O presente estudo comemorou o centenário do HC, destacando o papel e a importância deste biomaterial odontológico.

Agradecimentos: This study was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (Capes – Finance Code 001 and grants #A043-2013 and #1777/2014), by grants # 2011/19924-2, 2012/04870-7 and 2012/05903 of the São Paulo Research Foundation (Fapesp) and by grant #OAICE047-2017 of the University of Costa Rica Abstract: The purpose of this study was to describe the synthesis, characterization, and functionalization of b-NaYF4:30%Yb/0.5%Tm upconverting nanocrystals for use as nanofillers in a dental adhesive and microscopically evaluate the interface between the particles and a commercial adhesive. The upconverting nanoparticles were synthesized and purified by thermal decomposition, and their chemical composition determined by energy dispersive X-Ray spectroscopy. The crystalline structure was characterized using X-Ray diffraction and morphology and size were observed with scanning and transmission electron microscopy. Upconverting emission was evaluated by spectrophotometry irradiating the particles with a 975 nm diode laser. Particles were functionalized with polyacrylic acid and the success was confirmed by measurement of Zeta Potential and transmission electron microscopy. The results of X-ray diffraction found a pure hexagonal phase crystalline pattern. Scanning electron microscopy showed uniform dispersion of hexagonal-shaped particles of approximately 150 nm. Upconversion emission was observed in 344 nm, 361 nm, 450 nm, 474nm, 646 nm, 803 nm. Functionalization success was confirmed by formation of a stable aqueous colloid with a Zeta potential of -29.5mV and the absence of voids in the particle-adhesive interface on the transmission electron microscopy images. The reported synthesis and functionalization process produced upconverting nanoparticles emitting photons within the blue spectral region (450 nm and 474 nm) COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP Aberto

The purpose of this study was to describe the synthesis, characterization, and functionalization of b-NaYF4:30%Yb/0.5%Tm upconverting nanocrystals for use as nanofillers in a dental adhesive and microscopically evaluate the interface between the particles and a commercial adhesive. The upconverting nanoparticles were synthesized and purified by thermal decomposition, and their chemical composition determined by energy dispersive X-Ray spectroscopy. The crystalline structure was characterized using X-Ray diffraction and morphology and size were observed with scanning and transmission electron microscopy. Upconverting emission was evaluated by spectrophotometry irradiating the particles with a 975 nm diode laser. Particles were functionalized with polyacrylic acid and the success was confirmed by measurement of Zeta Potential and transmission electron microscopy. The results of X-ray diffraction found a pure hexagonal phase crystalline pattern. Scanning electron microscopy showed uniform dispersion of hexagonal-shaped particles of approximately 150 nm. Upconversion emission was observed in 344 nm, 361 nm, 450 nm, 474nm, 646 nm, 803 nm. Functionalization success was confirmed by formation of a stable aqueous colloid with a Zeta potential of −29.5mV and the absence of voids in the particle-adhesive interface on the transmission electron microscopy images. The reported synthesis and functionalization process produced upconverting nanoparticles emitting photons within the blue spectral region (450 nm and 474 nm).

Objective: To evaluate the remineralizing potential of a hydrocolloid-based, controlled fluoride-releasing system added to dentifrice formulas. Material and Methods: Sixty-five human enamel blocks were prepared and the surface microhardness (SH0) values were determined. The artificial caries lesions were induced and the demineralization surface microhardness (SH1) was evaluated. The blocks were randomly allocated into five groups (n = 13): (1) 100-TGF (100% NaF with Tara gum added); (2) 50-TGF (50% free NaF + 50% NaF with Tara gum added); (3) 100% TG (100% Tara gum without fluoride); (4) 100% NaF (positive control); and (5) placebo (without Tara gum and NaF). The blocks were submitted to 7 days pH cycling and treated with dentifrice slurries twice a day. Finally, surface hardness (SH2) was assessed and the percentage of surface hardness recovery (%SMHR) was calculated. Analysis of variance (ANOVA) followed by Bonferroni test was used for statistical analysis . Results: A positive %SMHR was found in the 100% NaF (5.07) and 50-TGF (0.64) groups, while the 100-TGF (-1.38), 100% TG (-3.88) and placebo (-0.52) did not undergo remineralization. Statistically significant differences were observed between 100% NaF and all the groups except for 50-TGF (p

The contribution of epigenetic mechanisms as a potential treatment model has been observed in cancer and autoimmune/inflammatory diseases. This review aims to put forward the epigenetic mechanisms as a promising strategy in implant surface functionalization and modification of biomaterials, to promote better osseointegration and bone regeneration, and could be applicable for alveolar bone regeneration and osseointegration in the future. Materials and Methods: Electronic and manual searches of the literature in PubMed, MEDLINE, and EMBASE were conducted, using a specific search strategy limited to publications in the last 5 years to identify preclinical studies in order to address the following focused questions: (i) Which, if any, are the epigenetic mechanisms used to functionalize implant surfaces to achieve better osseointegration? (ii) Which, if any, are the epigenetic mechanisms used to functionalize biomaterials to achieve better bone regeneration? Results: Findings from several studies have emphasized the role of miRNAs in functionalizing implants surfaces and biomaterials to promote osseointegration and bone regeneration, respectively. However, there are scarce data on the role of DNA methylation and histone modifications for these specific applications, despite being commonly applied in cancer research. Conclusions: Studies over the past few years have demonstrated that biomaterials are immunomodulatory rather than inert materials. In this context, epigenetics can act as next generation of advanced treatment tools for future regenerative techniques. Yet, there is a need to evaluate the efficacy/cost effectiveness of these techniques in comparison to current standards of care.

Three-dimensional (3D) printing, or additive manufacturing, is now a widely used tool in pre-operative planning, surgical teaching and simulator training. However, 3D printing technology that produces models with accurate haptic feedback, biomechanics and visuals for the training surgeon is not currently available. Challenges and opportunities in creating such surgical models will be discussed in this review paper. Surgery requires proper tissue handling as well as knowledge of relevant anatomy. To prepare doctors properly, training models need to take into account the biomechanical properties of the anatomical structures that will be manipulated in any given operation. This review summarises and evaluates the current biomechanical literature as it relates to human tissues and correlates the impact of this knowledge on developing high fidelity 3D printed surgical training models. We conclude that, currently, a printer technology has not yet been developed which can replicate many of the critical qualities of human tissue. Advances in 3D printing technology will be required to allow the printing of multi-material products to achieve the mechanical properties required.

Electronic skin, a kind of flexible electronic device and system inspired by human skin, has emerged as a promising candidate for wearable personal healthcare applications. Wearable electronic devices with skin-like properties will provide platforms for continuous and real-time monitoring of human physiological signals such as tissue pressure, body motion, temperature, metabolites, electrolyte balance, and disease-related biomarkers. Transdermal drug delivery devices can also be integrated into electronic skin to enhance its non-invasive, real-time dynamic therapy functions. This review summarizes the recent progress in electronic skin devices for applications in human health monitoring and therapy systems as well as several potential mass production technologies such as inkjet printing and 3D printing. The opportunities and challenges in broadening the applications of electronic skin devices in practical healthcare are also discussed.

The development of synthetic ways to fabricate nanosized materials with a well-defined shape, narrow-sized distribution, and high stability is of great importance to a rapidly developing area of nanotechnology. Here, we report an unusual reaction between amorphous two-line ferrihydrite and concentrated sulfuric or other mineral and organic acids. Instead of the expected dissolution, we observed the formation of new narrow-distributed brick-red nanoparticles (NPs) of hematite. Different acids produce similar nanoparticles according to scanning (SEM) and transmission electron microscopy (TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD), infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (EDX). The reaction demonstrates new possibilities for the synthesis of acid-resistant iron oxide nanoparticles and shows a novel pathway for the reaction of iron hydroxide with concentrated acids. The biomedical potential of the fabricated nanoparticles is demonstrated by the functionalization of the particles with polymers, fluorescent labels, and antibodies. Three different applications are demonstrated: i) specific targeting of the red blood cells, e.g., for red blood cell (RBC)-hitchhiking, ii) cancer cell targeting in vitro, iii) infrared ex vivo bioimaging. This novel synthesis route may be useful for the development of iron oxide materials for such specificity-demanding applications such as nanosensors, imaging, and therapy.

Objectives To investigate whether a different implant geometry with the same potential contact surface area (PCSA) affects the principal stress and strains in bone. Material and methods Three-dimensional finite-element models were created with a single endosseous implant embedded in bone. The irregular (IR) dental root-analog implant and regular (R) cylindrical implant with the same PCSA 350 mm were modeled, keeping the size of the thinnest implant wall 0.8 mm, and the thinnest bone wall 1 mm. The regular or irregular abutments were either 4.5 mm lower than the platform of the implants or 5 mm higher than the platform of the implants, both with the taper 1.44°. A 100 N vertical or 100 N vertical/50 N horizontal occlusal loading was applied. The biomechanical behaviors of periimplant bone were recorded. Results The IR implant design experienced lower periimplant stress and strain under oblique loading than that of R implant design. In the IR implant design, comparable stress in bone, implant, and abutment were found under 100 N vertical loading or 100 N vertical/50 N horizontal loading. In the R implant design, much higher stress in bone, implant, and abutment were found under 100 N vertical/50 N horizontal loading than that under 100 N vertical loading. Conclusion Irregular dental root-analog implant is a biomechanically favorable design principle for decreasing periimplant stress and strain under oblique loading.

Objective: To evaluate in vitro the antimicrobial effect of Listerine-green tea mouthwash on Streptococcus mutans (SM) in comparison with 0.12% Chlorhexidine (CHX) and Listerine-Zero. Material and Methods: The sensitivity and growth inhibition of SM bacterial species were evaluated and compared between Listerine-green tea, 0.12% CHX and Listerine-Zero mouthwashes. Sixty plates containing SM colonies were prepared in three groups (n=20), and growth inhibition zones were measured using the disk diffusion agar test in mm. Data were analyzed with SPSS 21. One-way ANOVA was used to compare the efficacy of the three mouthwashes tested. Post hoc Tukey tests were used for two-by-two comparisons. Statistical significance was defined at P

Dental biofilm is formed onto dental surfaces covered by a layer of specific salivary proteins and peptides named acquired enamel pellicle (AEP). It was previously demonstrated that the statherin- and histatin-derived engineered salivary peptides DR9-DR9 and DR9-RR14 were able to reduce enamel demineralization and displayed antimicrobial activity against Streptococcus mutans, respectively. However, these studies were carried under experimental conditions that did not mimic caries development induced by biofilm and sucrose exposure, the most cariogenic dietary sugar. In this thesis we assessed the effect of the engineered salivary peptides on 1) the adherence of S. mutans to hydroxyapatite (HAp), and 2) the reduction of enamel demineralization, using a validated S. mutans cariogenic biofilm model. We hypothesized that DR9-DR9 and DR9-RR14 would reduce S. mutans adherence and the cariogenicity of the biofilms, protecting enamel against demineralization. To test this hypothesis, we conducted two in vitro studies. In the first study, hydroxyapatite discs were treated with the peptides to induce AEP formation and then inoculated with S. mutans to quantify adhered bacteria, and to evaluate the total bacterial proteomes after adhesion periods of 2 h, 4 h, and 8 h. In the second study, a validated in vitro cariogenic S. mutans biofilm model was used to test the effect of DR9-DR9 and DR9-RR14 on enamel demineralization under two conditions 1) adsorbed onto the enamel surface forming the AEP, and 2) used to treat the biofilms 2x/day. Biofilms were grown for 144 h and the effect of the peptides on enamel demineralization, biomass, and total and extracellular matrix bacterial proteomes were evaluated. Results showed that DR9-DR9 reduced S. mutans adherence to HAp, but DR9-DR9 and DR9-RR14 did not have a significant effect on the development of the cariogenic biofilms formed. The engineered peptides did not modulate the bacterial proteome, neither when adhered to AEP nor when used to treat the biofilms during their formation. However, DR9-DR9 and DR9-RR14 significantly reduced enamel demineralization, suggesting that they control caries development by a physicochemical mechanism. The combinatory effect of reducing bacteria adhesion and limiting the mineral loss from the dental structure under high cariogenic challenge, suggests that the engineered peptides DR9-DR9 and DR9-RR14 represent a new translational approach for the prevention/treatment of dental caries.

This study evaluated the influence of activation modes, on Diametral Tensile Strength (DTS) of dual cured resin cements subjected to a Mechanical Fatigue test (MF). Four dual-cured resin cements (RelyX UNICEM [U], RelyX ARC [A], ENFORCE [E] and Nexus 2 [N]) were activated by three different curing modes as follows: Self-Curing (SC), Dual Cure activation with photoactivation executed directly (DC) and Dual Cure activation with Photoactivation Through Porcelain (DCTP). After 24 hours, half of the sample was subjected to 30.000 fatigue cycles at 1 Hz frequency and 12 N load. Then, all specimens were subjected to DTS test in Instron Universal Testing Machine and data were analyzed by three-way ANOVA and Tukey’s Test (5%). The results of DTS test means (MPa) and standard deviation, for each cement factor activated by SC, DC and DCTP was respectively: U (28.12 ± 5.29; 37.44 ± 6.49 and 40.10 ± 4.39), A (49.68 ± 8.42; 55.12 ± 5.16 and 63.43 ± 6.92), E (49.12 ± 3.89; 56.42 ± 8.88 and 56.96 ± 6.45) and N (61.89 ± 11.21; 59.26 ± 9.47 and 62.56 ± 10.93). Turkey’s test indicated that DC is related to the highest DTS values; Nexus 2 DTS remained the same independently of activation mode and that the Porcelain disk interposition enhanced DTS only for RelyX ARC the ANOVA statistical test indicated that MF didn’t alter the DTS values for all experimental groups. MF results clinical implication is that all cements tested exhibited, in an immediate loading, good cross linked bonds quality.

Bacterial cellulose (BC) is a nanocellulose form produced by some nonpathogenic bacteria. BC presents unique physical, chemical, and biological properties that make it a very versatile material and has found application in several fields, namely in food industry, cosmetics, and biomedicine. This review overviews the latest state-of-the-art usage of BC on three important areas of the biomedical field, namely delivery systems, wound dressing and healing materials, and tissue engineering for regenerative medicine. BC will be reviewed as a promising biopolymer for the design and development of innovative materials for the mentioned applications. Overall, BC is shown to be an effective and versatile carrier for delivery systems, a safe and multicustomizable patch or graft for wound dressing and healing applications, and a material that can be further tuned to better adjust for each tissue engineering application, by using different methods.

In recent years, naturally biodegradable polyhydroxyalkanoate (PHA) monopolymers have become focus of public attentions due to their good biocompatibility. However, due to its poor mechanical properties, high production costs, and limited functionality, its applications in materials, energy, and biomedical applications are greatly limited. In recent years, researchers have found that PHA copolymers have better thermal properties, mechanical processability, and physicochemical properties relative to their homopolymers. This review summarizes the synthesis of PHA copolymers by the latest biosynthetic and chemical modification methods. The modified PHA copolymer could greatly reduce the production cost with elevated mechanical or physicochemical properties, which can further meet the practical needs of various fields. This review further summarizes the broad applications of modified PHA copolymers in biomedical applications, which might shred lights on their commercial applications.