Effect of zinc-doping in physicochemical properties of dental adhesives

Purpose: To evaluate changes in the physicochemical properties, water sorption (WS), solubility (SO), modulus of elasticity (E), ultimate tensile strength (UTS), and microhardness (MH) tests were undertaken in zinc-doped dental adhesives.Methods: Two bonding resins, Adper Single Bond Plus (SB) and Clearfil SE Bond (SEB), were zincdoped by mixing them with 5, 10 or 20wt% of ZnO powder, or with 1 or 2wt% ZnCl2. Resin disks were made of each adhesive blend for the evaluation of WS, SO, and MH, and dumbbell-shaped specimens were prepared for E and UTS testing.Results: An increase in WS and SO was observed for adhesives doped with ZnCl2. A reduction in WS was observed for the adhesive blends containing 10% or 20wt% ZnO, while the SO was not altered in any of the ZnO-doped adhesives. An increase in E values was observed only for the SB adhesive doped with ZnCl2. For SEB-blends, the incorporation of zinc compounds did not alter the E values. UTS values decreased when SEB was doped with ZnO. SBblends doped with 20wt% ZnO significantly increased their MH, and the addition of zinc to the SEB-blends augmented the MH values in all cases.This investigation was supported by grants CICOM/FEDER MAT2014-52036P and AUIP-JA 201

In vitro mechanical stimulation facilitates stress dissipation and sealing ability at the conventional glass ionomer cement-dentin interface.

Objective: The aim of this study was to evaluate the induced changes in the chemical and mechanical performance at the glass-ionomer cement-dentin interface after mechanical load application. Methods: A conventional glass-ionomer cement (GIC) (Ketac Bond), and a resin-modified glass-ionomer cement (RMGIC) (Vitrebond Plus) were used. Bonded interfaces were stored in simulated body fluid, and then tested or submitted to the mechanical loading challenge. Different loading waveforms were applied: No cycling, 24 h cycled in sine or loaded in sustained hold waveforms. The cement-dentin interface was evaluated using a nano-dynamic mechanical analysis, estimating the complex modulus and tan δ. Atomic Force Microscopy (AFM) imaging, Raman analysis and dye assisted confocal microscopy evaluation (CLSM) were also performed. Results: The complex modulus was lower and tan delta was higher at interfaces promoted with the GIC if compared to the RMGIC unloaded. The conventional GIC attained evident reduction of nanoleakage. Mechanical loading favored remineralization and promoted higher complex modulus and lower tan delta values at interfaces with RMGIC, where porosity, micropermeability and nanoleakage were more abundant. Conclusions: Mechanical stimuli diminished the resistance to deformation and increased the stored energy at the GIC-dentin interface. The conventional GIC induced less porosity and nanoleakage than RMGIC. The RMGIC increased nanoleakage at the porous interface, and dye sorption appeared within the cement. Both cements created amorphous and crystalline apatites at the interface depending on the type of mechanical loading.This work was supported by the Ministry of Economy and Competitiveness (MINECO) and European Regional Development Fund (FEDER) [Project MAT2017-85999-P]

Ex vivo detection and characterization of remineralized carious dentin, by nanoindentation and single point Raman spectroscopy, after amalgam restoration

The aim of this study was to assess the mechanical and chemical performance of sound and caries-affected dentin (CAD), after Zn-free vs containing amalgam restorations placement and thermocycling. Dentin surfaces were studied by Atomic Force Microscopy (AFM) analysis for surface morphological characterization (including fibril diameter assessment), nano-indentation (to measure nano-hardness-Hi and modulus of Young-Ei), and single point Raman spectroscopy for chemical analysis. Measurements were performed before amalgam placement, after amalgam removal, and after 3 months of thermocycling (100,000cy/5 ºC and 55 ºC). Restorations increased both Hi and Ei at intertubular dentin of CAD. The highest values of Hi were achieved at intertubular dentin after restoring with Zn-containing amalgams. Remineralization of dentin was attributed to the increase of both amorphous and crystalline new mineral, as lower degrees of crystal imperfections in junction with crystal disorders, and improvement in structural stability of collagen were found. Higher presence of minerals were also confirmed after the decrease of fluoridated apatite and the increase of the total water content. Proteoglycans, lipids, and proteins, augmented in both sound and CAD, providing support for the mineral growing. The increase of bands assigned to vibration of carbonate calcium phosphate contributed to a decrease of crystallinity.Project MAT2014-52036-P supported by the Ministry of Economy and Competitiveness (MINECO) and European Regional Development Fund (FEDER)

Self-etching Zinc-doped adhesives improve the potential of caries-affected dentin to be functionally remineralized

The aim of this study was to evaluate if mechanical cycling influences bioactivity at the resin-carious dentin interface after bonding with Zn-doped self-etching adhesives. Caries-affected dentin (CAD) surfaces were bonded with: Clearfil SE Bond (SEB), and 10 wt% ZnO nanoparticles or 2 wt% ZnCl2 were added into the SEB primer or bonding components. Bonded interfaces were stored during 24 h, and then tested or submitted to mechanical loading. Microtensile bond strength (MTBS) was assessed. Debonded dentin surfaces were studied by field emission scanning electron microscopy (FESEM). Remineralization of the bonded interfaces was evaluated through nanohardness (Hi) and Young’s modulus (Ei), Raman spectroscopy/cluster analysis, and Masson's trichrome staining technique. Load cycling increased the percentage of adhesive failures. New precipitation of minerals composed of zinc-base salts and multiple Zn-rich phosphate deposits were observed in samples infiltrated with the Zn-doped adhesives. At the hybrid layer, specimens treated with ZnO incorporated in the primer (SEB·P-ZnO), after load cycling, attained the highest Ei and Hi. Load cycling increased Ei at the bottom of the hybrid layer when both, SEB un-doped and SEB with ZnCl2 included in the bonding (SEB·Bd-ZnCl2), were used. ZnO incorporated in the primer promoted an increase in height of the phosphate and carbonate peaks, crystallinity, relative mineral concentration, and lower collagen crosslinking. ZnCl2 included in the bonding attained similar results, but relative mineral concentration decreased, associated to higher crosslinking and restricted collagen maturation. Staining techniques permitted to observe no signs of exposed protein at the resin-dentin interface after using SEB·PZnO.This work was supported by grant MINECO/FEDERMAT2014-52036-P

Analysis of the porosity and microhardness of glass ionomer cements

© 2018 by the author(s) with the first publication right granted to the journal. This manuscript version is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by/4.0/ This document is the Published version of a Published Work that appeared in final form in Materials Science. To access the final edited and published work see https://doi.org/10.5755/j02.ms.28198Glass ionomer cements (GICs) are currently the first-choice materials in minimally invasive dentistry and are widely used in paediatric dentistry. The objective of this study was to evaluate the influence of viscosity and mixing on porosity and the relationship between the porosity and microhardness of GICs. Nine GICs were used: EQUIA® Forte Fil, Ionostar®Plus, 3MTMKetacTM Universal AplicapTM, Riva Light Cure HV®, Riva Silver®, Riva Protect®, VitremerTM, VitrebondTM Plus and Activa BioActive RestorativeTM. Samples were prepared from each material and images were obtained by scanning electron microscopy (SEM). Using software, the number and diameter of pores, area, and percentage of area they occupied were measured. After SEM analysis, the samples were used to make surface microhardness (SMH) measurements. Ionostar® Plus, EQUIA® Forte Fil and Riva Light Cure HV® had the highest number of pores. Riva Protect® had the largest pores and the highest percentage of pore-occupied area, while Activa BioActive RestorativeTM and VitrebondTM Plus had a smaller pore size and a smaller percentage by area. Riva Silver® and EQUIA® Forte Fil showed the highest microhardness values and VitrebondTM Plus and VitremerTM the lowest. In conclusion, when the cement viscosity is low, the type of mixture determines the degree of porosity, but has less influence when viscosity is high. There was no correlation between microhardness and the porosity of GICs

Functional and molecular structural analysis of dentine interfaces promoted by a Zn-doped self-etching adhesive and an in vitro load cycling model

The aim of this study was to evaluate if mechanical cycling influences bioactivity and bond strength of resin–dentine interface after bonding with Zn-doped self-etching adhesives. Sound dentine surfaces were bonded with Clearfil SE Bond (SEB), 10 wt% ZnO microparticles or 2 wt% ZnCl2 were added into the SEB primer (P) or bonding (Bd) for Zn-doping. Bonded interfaces were stored in simulated body fluid (24 h), and then tested or submitted to mechanical loading. Microtensile bond strength testing was performed. Debonded dentine surfaces were studied by scanning electron microscopy. Remineralisation of the bonded interfaces was assessed by nano-indentation, Raman spectroscopy, and Masson׳s trichrome staining. Load cycling (LC) increased the percentage of adhesive failures in all groups. LC increased the Young׳s modulus (Ei) at the hybrid layer (HL) when SEB, SEB·P-ZnO and SEB·P-ZnCl2 were applied, but decreased when both ZnO and ZnCl2 were incorporated into the bonding. Ei was higher when Zn compounds were incorporated into the primer (SEB·P). ZnO promoted an increase, and ZnCl2 a decrease, of both the relative presence of minerals and crystallinity, after LC. LC increased collagen crosslinking with both SEB·P-ZnO and SEB·P-ZnCl2. The ratios which reflect the nature of collagen increased, in general, at both HL and BHL after LC, confirming recovery, better organisation, improved structural differences and collagen quality. After loading, trichrome staining reflected a deeper demineralised dentine fringe when Zn-doped compounds were incorporated into SEB·Bd. Multiple Zn-rich phosphate deposits and salt formations were detected. Mineral precipitates nucleated in multilayered platforms or globular formations on peritubular and intertubular dentine.This work was supported by grant MINECO/FEDER MAT2011-24551 and MAT2014-52036-P

Orthodontic and dentofacial orthopedic treatments in patients with ectodermal dysplasia: a systematic review

© The Author(s) 2022. This manuscript version is made available under the CC-BY 4.0 license http://creativecommons.org/licenses/by/4.0/ This document is the Published version of a Published Work that appeared in final form in Orphanet Journal of Rare Diseases. To access the final edited and published work see https://doi.org/10.1186/s13023-022-02533-0Objective The objective of this systematic review was to determine the orthodontic and dentofacial orthopedic treatments carried out in patients with ectodermal dysplasia to facilitate functional and aesthetic rehabilitation. Methods The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement. We systematically searched PubMed, Web of Science, Scopus, Scielo, LILACS, EBSCOhost and Embase databases up to 6 January 2022. We included articles describing patients with any type of ectodermal dysplasia who received orthodontic or dentofacial orthopedic treatment to facilitate functional and aesthetic oral rehabilitation. The search was not restricted by language or year of publication. The quality of the studies was assessed using the Joanna Briggs Institute Quality Assessment Scale of the University of Adelaide for case series and case reports. The review was registered at the University of York Centre for reviews (CRD42021288030). Results Of the initial 403 studies found, 29 met the inclusion criteria. After applying the quality scale, 23 were left for review—21 case reports and 2 case series. The initial age of patients ranged from 34 months to 24 years. Thirteen studies were on hypohidrotic and/or anhidrotic ectodermal dysplasia, of which two were X-chromosome linked. In one study, the patient had Wiktop syndrome, and in nine the type of ectodermal dysplasia was not specified. The duration of treatment was 7 weeks to 10 years. The treatments described were: fixed orthodontic appliances or simple acrylic plates designed for tooth movement, including leveling and aligning, closing of diastemata, retraction of impacted teeth in the dental arch; clear aligners; fixed and/or removable appliances for the correction of skeletal and/or dentoalveolar relationships; palatal expanders in combination with face masks for orthopedic traction of the maxilla; and orthognathic surgery. Only three studies provided cephalometric data. Conclusion The level of evidence of the articles reviewed was low and most orthopedic and dentofacial orthodontic treatments described were focused on correcting dental malpositioning and jaw asymmetries and not on stimulating growth from an early age. Studies with greater scientific evidence are needed to determine the best treatment for these patients

On modeling and nano-analysis of caries-affected dentin surfaces restored with Zn-containing amalgam and in vitro oral function

The aim of this research was to assess the influence of mechanical loading on the ability of Zn-free vs Zn-containing amalgams to promote remineralization at the dentin interface. Sound (SD) and caries-affected dentin surfaces (CAD) were restored using Zn-free or Zn-containing dental amalgams. Mid-coronal dentin surfaces were studied by 1) Atomic Force Microscopy (AFM) analysis (including plot and phase imaging, nanoindentation test (modulus of Young (Ei), nano-roughness measurements, and fibril diameter assessment), 2) Raman spectroscopy/cluster analysis, 3) X-ray diffraction (μXRD2), 4) field emission electron microscope (FESEM) and energy-dispersive analysis (EDX), for morphological, mechanical, and physico-chemical characterization. Analyses were performed before amalgam placement and after amalgam removal, at 24 hours and 3 weeks of load cycling. Zn-free and Zn-containing amalgams restorations promoted an increase in the modulus of Young of CAD surfaces, after three weeks of load cycling; at this time, Zn-containing amalgams attained higher Ei than Zn-free restorations. Zn-containing amalgams induced tubular occlusion after load cycling, in both sound and CAD. Zn free-amalgams promoted remineralization of both intertubular and peritubular dentin in CAD substrata. These minerals were identified as calciumphosphate deposits, and crystals as hydroxyl-apatite with augmented crystallographic maturity but with some components of lattice distortion. Crosslinking of collagen diminished and secondary structure of collagen increased in CAD substrate restored with Zn-containing amalgam after 3 w of load cycling, indicating an advanced preservation, molecular organization and orientation of collagen fibrils after load cycling. Plot and phase images permitted to observe the topographical changes which were promoted by the mineral deposits; in general, the indexes related to higher remineralization gave rise to a decrease of nano-roughness and an augmentation of the bandwidth of the collagen fibrils. Zn-containing amalgam restorations submitted to mechanical stimuli promote remineralization of the partially mineral-depleted subjacent substrate at the caries-affected dentin.This work was supported by Grant Nos. MINECO/FEDER MAT2014-52036-P and FIS2013-41821-R

Design and evaluation of a booklet for the Oral Health Program in children from birth

© 2021 Departamento de Salud del Gobierno de Navarra. This manuscript version is made available under the CC-BY-SA 4.0 license http://creativecommons.org/licenses/by-sa/4.0/ This document is the Published version of a Published Work that appeared in final form in Anales del Sistema Sanitario de Navarra. To access the final edited and published work see https://doi.org/10.23938/ASSN.0959Fundamento En España no existe un control preventivo de la salud bucodental desde el nacimiento. Esto conlleva una serie de riesgos, como el aumento de caries en niños. El objetivo de este trabajo fue diseñar una cartilla odontopediátrica para la valoración y seguimiento clínico de la salud bucodental en niños, así como su evaluación por profesionales de la salud y progenitores/tutores. Método Diseño de la cartilla, en 2018, por odontopediatras de la Clínica Odontológica Universitaria de Murcia, a partir de una revisión bibliográfica, para instruir en hábitos preventivos (dietéticos e higiene bucodental) y curativos (planificación de visitas y tratamientos odontopediátricos). Evaluación del diseño preliminar, en 2019, por un grupo de cuarenta odontopediatras, odontólogos, pediatras y progenitores/tutores, muestreados por conveniencia. Cumplimentaron un cuestionario con sus datos, opinión sobre distintos aspectos de la cartilla y sugerencias. Resultados La evaluación de la versión preliminar de la cartilla por profesionales de salud y progenitores/tutores fue positiva; se modificó atendiendo a sus sugerencias y se confeccionó la versión final: cartilla de 16 páginas, con datos de filiación del niño y progenitores/tutores, con enfoque preventivo y curativo, haciendo coincidir en el tiempo revisiones pediátricas y odontopediátricas. Conclusiones La cartilla odontopediátrica se ha creado y ha sido valorada positivamente por distintos profesionales y tutores. Se recomienda su uso para la atención odontológica temprana, pudiendo ampliarse a otros sistemas de salud a nivel autonómico en España.-------------------------------------Background There is no preventive control of oral health from birth in Spain. This situation entails a number of risks, such as increased caries lesions in children. The objective of this study was to design a pediatric dentistry booklet for the clinical assessment and follow-up of oral health in children, as well as its evaluation by health professionals and parents. Method Design of the booklet, in 2018, by pediatric dentists of the Murcia University Dental Clinic, based on a bibliographic review, to instruct in preventive (dietary and oral hygiene) and curative (planning of pediatric dental visits and treatments) habits. A convenience sampling of forty pediatric dentists, dentists, pediatricians and parents was carried out to evaluate the preliminary design, in 2019. They completed a questionnaire with their data, opinion on different aspects of the booklet and suggestions. Results The evaluation of the preliminary version of the booklet by health professionals and parents was positive. It was modified in line with their suggestions and the final version was made: a 16-page booklet, with data on the child's affiliation and parents, with a preventive and curative approach, making pediatric and pediatric dental check-ups coincide in time. Conclusions The pediatric dentistry booklet was created and has been positively valued by professionals and parents, its use is recommended for early dental care, and can be extended to other health systems at the regional level in Spain

Total and soluble fluoride concentration in children's toothpastes in Spain

© 2021 Los autores. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Published version of a Published Work that appeared in final form in Revista Española de Salud Pública.El uso de pastas dentales fluoradas es considerado el método más racional en el control de caries dental, y es recomendado para personas de todas las edades, pero para ello han de establecerse en una concentración mínima de 1.000 ppm de fluoruro total soluble, en pacientes pediátricos. El objetivo del estudio fué determinar la concentración de fluoruro total y soluble presente en pastas dentales comercializadas en España para uso pediátrico. Se realizó un estudio descriptivo y transversal durante el año 2019, analizando 11 pastas dentales de uso pediátrico comercializadas en Murcia, España. Se analizó la concentración de fluoruro (ppm F=mg F/kg) total (FT), soluble (FTS) e ión de Flúor (F) y de MFP (FPO32-) mediante un electrodo ion-específico acoplado a un analizador de iones. Se llevó a cabo un estudio descriptivo determinando las medias y desviaciones estándar para cada variable. Entre las pastas dentales analizadas, el 45% contenían NaF (fluoruro sódico), 45% MFP (monofluorofosfato de sodio) y un 10 % ambos tipos de sales. El abrasivo de todas era sílice. El 98% de las pastas dentales analizadas mostraban contenidos de flúor total similares a los descritos por el fabricante, solamente 3 pastas presentaban concentraciones de flúor inferiores a las descritas por el fabricante. El rango obtenido de FT oscilaba entre 398-1.474,6 ppm F, y el 100% de las pastas dentales no mostraron diferencias entre valores de flúor total y flúor soluble. La mayoría de las pastas dentales analizadas contienen una concentración de flúor soluble entre 1.000-1.500 ppm F, correspondiéndose con los valores descritos por los fabricantes. Sin embargo, todavía existen pastas dentales con valores inferiores a los recomendados de mínimo de 1.000 ppm F que no permiten tener la actividad anticaries efectiva desde el punto de vista de salud pública. --------------------------------The use of fluoridated toothpastes is considered the most rational method in dental caries control, and it is recommended for all ages people, but for this they must be established at a minimum concentration of 1,000 ppm of total soluble fluoride, in pediatric patients. The objective of the study was to determine the concentration of total and soluble fluoride present in toothpastes marketed in Spain for pediatric use. A descriptive and cross-sectional study was carried out throughout 2019, analyzing 11 toothpastes for pediatric use marketed in Murcia, Spain. The concentration of fluoride (ppm F=mg F/Kg) total (FT), soluble (FTS) and fluoride ion (F) and MFP (FPO32-) was analyzed using an ion-specific electrode coupled to an ion analyzer. A descriptive study was carried out to determinate mean and standard deviations for each variable analyzed. Among the analyzed toothpastes, 45% contained NaF (sodium fluoride), 45% MFP (sodium monofluorophosphate) and 10% both types of salts. The abrasive used was silica. 98% of the analyzed toothpastes showed total fluoride contents similar to those described by the manufacturer, only 3 toothpastes had fluoride concentrations lower than those described. The range obtained from FT oscillated between 398 -1,474.6 ppm F, and 100% of the toothpastes did not show differences between values of total fluoride and soluble fluoride. Most of the analyzed toothpastes contain a concentration of soluble fluoride between 1,000-1,500 ppm Fluoride, corresponding to the values described by the manufacturers However, there are still toothpastes with values lower than those recommended, minimum 1,000 ppm F, that do not allow effective anticaries activity from a public health point of vie