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1.
PLoS One ; 17(2): e0262435, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35108296

RESUMEN

This paper explores the potential of combining different isotope systems from different tissues to improve resolution when reconstructing breastfeeding and weaning practices (BWP) in archaeology. Additionally, we tested whether changes in diet can be detected in deciduous teeth. Rib collagen samples from 22 infants/children from the archaeological site of Bacuranao I (Mayabeque, Cuba) were processed for nitrogen (δ15N) and carbon (δ13Cco) stable isotopes and assessed using a Bayesian model (WARN). In addition, enamel of 48 teeth from 30 infants/children were analyzed for oxygen (δ18Oen) and carbon (δ13Cen) stable isotopes. Data revealed that the timing of weaning cannot be characterized precisely by analyzing either δ18O or δ15N. While a depletion in both δ15N and δ13Cco is only evident after one year, the WARN model suggested that the weaning process started at around 3 months and ended around 1.7 years. Most teeth were enriched in δ18Oen compared to deciduous incisors, suggesting a breastfeeding signal. However, a high variability in δ18O was found between similar teeth from the same individuals. Higher enrichment in δ18Oen, and variability, was observed in tissues formed during the first six months of life. A δ13C enrichment of 1.0‰ was observed among deciduous teeth and ribs. While most individuals enriched in δ15N showed enrichment in δ13C, the δ18O values were more variable. Our data suggests that stable isotopes of deciduous teeth, especially δ13Cen, can be used to detect changes in diet during the weaning process. It is also possible that the δ18O enrichment observed in M1 is influenced by the effects of cooking techniques on weaning foods. The combination of multiple isotope systems and tissues overcome some of the limitations posed by single tissue approaches.


Asunto(s)
Arqueología , Lactancia Materna , Destete , Teorema de Bayes , Lactancia Materna/historia , Isótopos de Carbono/análisis , Colágeno/química , Cuba , Historia Antigua , Humanos , Isótopos de Nitrógeno/análisis , Isótopos de Oxígeno/análisis , Diente Primario/química
2.
Sci Rep ; 11(1): 20780, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34675271

RESUMEN

Examine the effect of dental curing light and laser treatments applied after Silver Diamine Fluoride (SDF) on dentin hardness in carious primary molars. This in-vitro study consisted of 30 extracted primary molars with caries extending into dentin without pulpal involvement. The collected teeth were randomly divided into three groups: group 1: received SDF then Sub-ablative low-energy of Er,Cr:YSGG laser, group 2: received SDF followed by application of curing light for 40 s, group 3: had SDF treatment only. In all groups, 38% Ag (NH3)2F SDF was used. Vickers hardness test was performed on sound dentin below carious lesion. Kruskal-Wallis Test was used to determine the mean difference in dentin hardness of the groups at 5% Significance level using SPSS software. Surface hardness of sound dentin below the carious lesion was statistically significantly higher in the laser + SDF group (891.24 ± 37.33 kgf/mm2) versus the two other groups (Light cure + SDF = 266.65 ± 90.81 kgf/mm2 and SDF only = 117.91 ± 19.19 kgf/mm2) with p-value ≤ 0.001. Although Photopolymerization of SDF increases the surface hardness of sound dentin below the carious lesion, applying laser after SDF has the highest surface hardness due to the laser's sub-ablation of dentin.


Asunto(s)
Luces de Curación Dental , Láseres de Estado Sólido , Polimerizacion , Compuestos de Amonio Cuaternario/química , Compuestos de Plata/química , Diente Primario/química , Fluoruros Tópicos/química , Pruebas de Dureza , Humanos
3.
Biomed Res Int ; 2021: 5534294, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33869625

RESUMEN

AIM: Root canal filling materials have the tendency to inhibit adhesion of resin-based composites. This study was aimed at evaluating the effect of root canal filling materials and their solvents on the shear bond strength (SBS) of resin composite with the primary tooth dentin. METHODS AND MATERIALS: Seventy-two intact anterior primary teeth were selected. Smooth dentinal surfaces were prepared to a minimum diameter of 3 mm and thickness of 1.5-2.0 mm. The samples were equally divided into six groups (n = 12). In group 1: control group, no root filling material; in group 2: Metapex, no solvent; in group 3: Metapex+ethanol solvent; in group 4: ZOE, no solvent; in group 5: ZOE+ethanol solvent; and in group 6: ZOE+orange oil solvent were applied. Then, dentin surfaces were etched, and composite restorations were placed and cured. The specimens were stored in distilled water at 37°C for 24 hours. SBS values were determined using a universal testing machine. RESULTS: The SBS values of composite to dentin in groups 2 and 4 were significantly lower than those in the control group (P < 0.001). Cleansing of the specimens with 96% ethanol after removal of Metapex significantly increased the composite-dentin bond (P < 0.001). Applying ZOE, only orange oil solvent significantly increased the SBS of the composite to the primary tooth dentin (P = 0.01). CONCLUSION: To reduce the negative effects of endodontic root filling materials on the SBS of composite and primary tooth dentin, ethanol is a suitable solvent when Metapex is used, while orange oil might be a better choice than ethanol when applying ZOE.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo , Dentina/efectos de los fármacos , Materiales de Obturación del Conducto Radicular/farmacología , Resistencia al Corte/efectos de los fármacos , Solventes/química , Diente Primario/química , Dentina/ultraestructura , Humanos , Propiedades de Superficie
4.
Arch Oral Biol ; 118: 104850, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32736142

RESUMEN

OBJETIVES: The neonatal line (NNL) in enamel is hypomineralized, but quantitative data on the enamel component volumes of the NNL are lacking. This study aimed at quantifying the variation in the mineral, organic, and water volumes at the NNL and in pre- and postnatal enamel. MATERIALS AND METHODS: In buccal enamel longitudinal ground sections of exfoliated primary incisors (upper and lower; n = 17), the enamel component volumes were quantified at five histological sites (located at 40 µm intervals along a transversal line): the NNL, two sites in prenatal enamel, and two sites in postnatal enamel. Mineral volume was quantified using microradiography, and non-mineral volumes were quantified using polarizing microscopy. RESULTS: Differences in component volumes between the NNL and pre- and postnatal enamel had high effect sizes (Hedge's G ranging from 0.89, for the water volume, to 1.88, for the mineral volume; power > 90 %). The distance from the NNL correlated with the normalized component volume: r = 0.459, 95 % CI = 0.274/0.612 (mineral); r = -0.504; 95 % CI= -0.328/-0.647 (organic), and r = -0.294; 95 % CI= -0.087/-0.476 (water). Approaching the NNL from postnatal enamel, the percentage differences in component volumes were: -1.93 to -3.22 % for the mineral volume, +21.26 to +35.42 % for the organic volume, and +3.86 to +6.03 % for the water volume. Towards postnatal enamel, the percentage differences had the opposite trend. CONCLUSIONS: The enamel NNL is slightly hypomineralized with an increased organic volume one order of magnitude higher than the percentage differences in both mineral and water volumes.


Asunto(s)
Esmalte Dental/química , Minerales , Agua , Esmalte Dental/embriología , Femenino , Humanos , Microrradiografía , Embarazo , Diente Primario/química
6.
Arch Oral Biol ; 104: 90-102, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31176148

RESUMEN

OBJECTIVES: Our first objective was to review the evidence describing the appearance and microstructure of the neonatal line in human deciduous teeth and to link this with known changes in neonatal physiology occurring at and around birth. A second objective was to explore ways to improve identification of the neonatal line by mapping the pre- and postnatal distribution of Ca, Sr and Zn in deciduous cuspal enamel and superimposing these maps onto transmitted light micrographs that included a clear true section of the neonatal line. MATERIALS AND METHODS: We used synchrotron X-ray fluorescence to map elemental distributions in pre- and postnatal enamel and dentine. Two deciduous canines and 5 deciduous molars were scanned with an X-ray beam monochromatised to 17.0 keV at either 10.0, 2.5 or 1.0 µm resolution and 10 ms integration time. RESULTS: Calcium maps distinguished enamel and dentine but did not clearly demarcate tissues formed pre- or postnatally. Strontium maps reflected presumed pre- and postnatal maternal serum levels and what are likely to be diet-dependent regions of Sr enrichment or depletion. Prenatal Zn maps, particularly for dentine, mirror elevated levels in the fetus and in colostrum during the first few days of life. CONCLUSIONS: The neonatal line, enamel dentine junction and surface enamel were all Zn-rich. Within the neonatal line Zn may be associated with increased crystallinity but also with caries resistance, both of which have been reported previously. Elemental mapping may improve the identification of ambiguous NNLs and so be useful in forensic and archaeological studies.


Asunto(s)
Calcio , Estroncio , Sincrotrones , Diente Primario , Zinc , Calcio/análisis , Femenino , Fluorescencia , Humanos , Recién Nacido , Embarazo , Estroncio/análisis , Diente Primario/química , Rayos X , Zinc/análisis
7.
Environ Res ; 171: 444-451, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30735952

RESUMEN

A growing number of studies have examined associations of metal exposures with birth outcomes, however, results from these studies have been inconsistent, and hampered by methodological limitations. We measured direct fetal exposure to three metals (lead, manganese and zinc) during the second and third trimester and examined its association with birth weight and gestational age at delivery. Participants in the Wayne County Health, Environment, Allergy and Asthma Longitudinal Study (WHEALS), a population-based birth cohort established between September 2003 and December 2007, were invited to donate teeth to the study. Lead, manganese and zinc during the second and third trimesters were measured via high-resolution microspatial mapping of dentin growth rings, a validated biomarker for prenatal metal exposure. Gestational age at delivery and infant birth weight were obtained from the delivery medical record. A total of 145 children had tooth metal measurements and birth outcome data. Mean birth weight was 3431 ±â€¯472 g and mean gestational age at delivery was 39.0 ±â€¯1.3 weeks. Overall, there was a positive association between second (ß = 0.21, 95% CI: 0.05, 0.37, P = 0.01) and third trimester (ß = 0.21, 95% CI: 0.05, 0.37, P = 0.01) tooth manganese and birth weight Z-score; this remained statistically significant after covariate adjustment. There was also a negative association between second trimester tooth lead level and birth weight Z-score (ß = -0.20, 95% CI: -0.38, -0.02, P = 0.02), however, this was attenuated after adjusting for covariates. Mixture analysis revealed similar findings. There was evidence for a sex-specific effect of manganese with birth weight Z-score, with the association stronger in female compared to male infants. Overall, we found evidence suggesting that higher in utero manganese is associated with larger birth weight Z-scores and that these associations may vary by infant sex.


Asunto(s)
Contaminantes Ambientales/análisis , Metales/análisis , Diente Primario/química , Peso al Nacer , Niño , Femenino , Humanos , Lactante , Plomo , Estudios Longitudinales , Masculino , Exposición Materna , Michigan , Ohio , Embarazo
8.
Biol Trace Elem Res ; 187(1): 65-73, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29796983

RESUMEN

Nickel and chromium existing in stainless-steel crowns (SSCs, used in pediatric dentistry) might be cytotoxic and allergenic. However, no in vivo studies have examined their salivary levels in children using SSCs, or in young children without SSCs. Also, the effect of acidity on metal ion release has not yet been evaluated in any previous in vivo studies in the whole literature. Therefore, this preliminary before-after clinical trial was conducted. Salivary nickel/chromium levels of 30 children before and after 2 months of placement of SSCs were measured using atomic absorption spectrophotometry. Salivary pH was measured with a digital pH meter. The effects of treatment, pH, number of SSCs, gender, and age on salivary ions were analyzed statistically (α = 0.05, ß = 0.15). Salivary nickel concentrations increased from 4.9010 ± 4.7390 to 5.6320 ± 4.7210 µg/L (P = 0.000, paired t test). Chromium increased from 0.3273 ± 0.5214 to 0.4199 ± 0.6404 µg/L (P = 0.016). Saliva pH increased from 6.81 ± 0.52 to 7.04 ± 0.47 (P = 0.000). Ion levels were not correlated with pH (P > 0.14), except chromium in the follow-up (rho = - 0.435, P = 0.016). Nickel increase (but not chromium increase) was correlated with pH increase (rho = 0.367, P = 0.046). Age was only correlated with baseline chromium (rho = 0.373, P = 0.042). Being male was associated with baseline/follow-up nickel levels (P ≤ 0.030). SSC number was not correlated with ions or pH (P > 0.36). It was shown for the first time that SSCs might increase salivary nickel and chromium concentrations and reduce saliva acidity. Nickel increase might be in line with pH elevation. The raised pH might be associated with reduced chromium release. Boys might have higher nickel levels than might girls, with or without SSCs.


Asunto(s)
Cromo/análisis , Coronas , Níquel/análisis , Saliva/química , Acero Inoxidable/química , Diente Primario/química , Niño , Preescolar , Cromo/administración & dosificación , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Níquel/administración & dosificación
9.
J Appl Biomater Funct Mater ; 17(2): 2280800018784230, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30045659

RESUMEN

BACKGROUND: Great interest has recently been focused on tooth and tooth derivatives as suitable substrates for the treatment of alveolar bone defects. Here, we propose the use of demineralized baby teeth (BT) as potential grafting materials for bone augmentation procedures. METHODS: Particles of human BT (Ø < 1 mm) were demineralized by means of a chemical/thermal treatment. Demineralized BT particles were thoroughly characterized by scanning electron microscopy/energy dispersive X-ray analyses to evaluate the effects of the demineralization on BT topography and mineral phase composition, and by enzyme-linked immunosorbent assays (ELISA) to quantify collagen and bone morphogenetic protein-2 (BMP-2) protein contents. The response of SAOS-2 cells to exogenous BMP-2 stimulation was evaluated to identify the minimum BMP-2 concentration able to induce osteodifferentiation in vitro (alkaline phosphatase (ALP) activity). RESULTS: The demineralization treatment led to a dramatic decrease in relative Ca and P content (%) of ≈75% with respect to the native BT particles, while preserving native protein conformation and activity. Interestingly, the demineralization process led to a rise in the bioavailability of BMP-2 in BT particles, as compared to the untreated counterparts. The BMP-2 content found in demineralized BT was also proved to be very effective in enhancing ALP activity, thus in the osteodifferentiation of SAOS-2 cells in vitro, as confirmed by cell experiments performed upon exogenously added BMP-2. CONCLUSIONS: In this study we demonstrate that the BMP-2 content found in demineralized BT is very effective in inducing cell osteodifferentiation, and strengthens the idea that BTs are very attractive bioactive materials for bone-grafting procedures.


Asunto(s)
Proteína Morfogenética Ósea 2/análisis , Colágeno Tipo I/análisis , Diente Primario/metabolismo , Técnica de Desmineralización de Huesos , Proteína Morfogenética Ósea 2/química , Proteína Morfogenética Ósea 2/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Colágeno Tipo I/química , Humanos , Osteogénesis/efectos de los fármacos , Propiedades de Superficie , Diente Primario/química
10.
Am J Phys Anthropol ; 167(3): 644-655, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30132793

RESUMEN

OBJECTIVES: Isotope ratio analyses of dentine collagen were used to characterize short-term changes in physiological status (both dietary status and biological stress) across the life course of children afforded special funerary treatment. MATERIALS AND METHODS: Temporal sequences of δ15 N and δ13 C isotope profiles for incrementally forming dentine collagen were obtained from deciduous teeth of 86 children from four early-medieval English cemeteries. Thirty-one were interred in child-specific burial clusters, and the remainder alongside adults in other areas of the cemetery. Isotope profiles were categorized into four distinct patterns of dietary and health status between the final prenatal months and death. RESULTS: Isotope profiles from individuals from the burial clusters were significantly less likely to reflect weaning curves, suggesting distinctive breastfeeding and weaning experiences. This relationship was not simply a factor of differential age at death between cohorts. There was no association of burial location neither with stage of weaning at death, nor with isotopic evidence of physiological stress at the end of life. DISCUSSION: This study is the first to identify a relationship between the extent of breastfeeding and the provision of child-specific funerary rites. Limited breastfeeding may indicate the mother had died during or soon after birth, or that either mother or child was unable to feed due to illness. Children who were not breastfed will have experienced a significantly higher risk of malnutrition, undernutrition and infection. These sickly and perhaps motherless children received care to nourish them during early life, and were similarly provided with special treatment in death.


Asunto(s)
Entierro/historia , Isótopos de Carbono/análisis , Dieta/historia , Isótopos de Nitrógeno/análisis , Antropología Física , Lactancia Materna , Niño , Preescolar , Inglaterra , Historia Medieval , Humanos , Lactante , Recién Nacido , Diente Primario/química , Destete
11.
Caries Res ; 52(4): 303-311, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29408818

RESUMEN

The objectives of the study were to quantify the dentine mineral concentration (DMC) in teeth restored conventionally, according to the atraumatic restorative treatment (ART) and ultraconservative (UCT) protocols (open cavities and small ART restorations), and the DMC underneath the open cavities of teeth managed by UCT versus nontreated, open cavities. We studied 50 teeth with restorations/open cavities, 39 restored teeth (9 by conventional restorative treatment [CRT], 17 by ART, and 13 by UCT) and 16 teeth with open cavities. Each restoration/open cavity was scanned using microcomputed tomography, with 3 hydroxyapatite disks with respective densities of 1.24, 1.33, and 1.57 g/cm3 as a reference. Images were reconstructed and the greyscale images were converted into DMC values. For each restoration/open cavity, 15 measurements of dentine immediately underneath and from the corresponding area in sound dentine were taken. DMC was expressed as a percentage of the DMC of sound dentine. ANOVA and the Student t test were used for statistical analysis. The mean DMC underneath restorations of the ART protocol group (98.93%) was statistically significantly higher than that of the UCT protocol group (91.98%), but not of the CRT protocol group (91.33%). On multiple surfaces, mean DMC in the axial area (94.32%) was statistically significantly higher than in the gingival area (92.80%). The mean DMC of open cavities managed by UCT protocol (89.05%) was statistically significantly higher than in nontreated open cavities (83.90%). In conclusion, a dentine-hypermineralized area underneath ART restorations was observed. Managing open cavities with a toothbrush and fluoride toothpaste (the UCT protocol) resulted in higher mineralized dentine underneath the cavity than in nontreated open cavities.


Asunto(s)
Caries Dental/metabolismo , Caries Dental/terapia , Restauración Dental Permanente/métodos , Dentina/química , Minerales/análisis , Diente Molar/química , Diente Primario/química , Cariostáticos/administración & dosificación , Niño , Caries Dental/diagnóstico por imagen , Durapatita , Fluoruros Tópicos/administración & dosificación , Humanos , Procesamiento de Imagen Asistido por Computador , Diente Molar/diagnóstico por imagen , Fantasmas de Imagen , Diente Primario/diagnóstico por imagen , Cepillado Dental , Microtomografía por Rayos X
12.
Microsc Res Tech ; 81(5): 509-514, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29430843

RESUMEN

The chemical compositions (organic and inorganic contents) and mechanical behaviors of the dentin of permanent and deciduous teeth were analyzed and compared using X-ray fluorescence spectrometry (µ-EDXRF) Fourier transform Raman spectroscopy (FT-Raman) and a microhardness test (HD). Healthy fresh human primary and permanent molars (n = 10) were selected, The buccal surfaces facing upwards were stabilized in an acrylic plate, flattened, polished, and submitted to the µ-EDXRF, FT-Raman, and HD analysis. The results of the analysis were subjected to ANOVAs and Mann-Whitney U/Student's t multiple comparisons tests. The data showed similar values for the dentin of the primary and permanent teeth in P content, organic content (amide I peak), inorganic content ( PO43- - 430 and 590), and microhardness, Nevertheless, Ca content and Ca/P weight ratio were higher, and the CO32- peak was lower in the dentin of the permanent teeth compared to primary teeth. It be concluded that despite permanent teeth showed more Ca element, both substrates showed similar behavior of chemical and physical properties.


Asunto(s)
Dentina/química , Espectrometría Raman/métodos , Diente Primario/química , Análisis de Varianza , Esmalte Dental/química , Humanos , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X
13.
J Appl Oral Sci ; 26: e20170053, 2018 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-29364339

RESUMEN

To evaluate the effect of erosive challenges on the tooth- restoration interface of deciduous teeth treated with different adhesive protocols. Deciduous molars were cut mesiodistally, then embedded, abraded and polished (n=80). Samples were randomly divided according to the adhesive system used into: G1 (Adper Single Bond2®, etch-and-rinse), G2 (Universal Single Bond®, self-etching), G3 (OptibondFL®, etch-and-rinse with Fluoride) and G4 (BondForce®, self-etching with Fluoride). After standardized cavity preparation (2 mm diameter x 2 mm depth), adhesive systems were applied and samples were restored (composite resin Z350®). Half of the samples were exposed to erosive/abrasive cycles (n = 10, each adhesive group), and the other half (control group; n = 10) remained immersed in artificial saliva. For microleakage analysis, samples were submersed in methylene blue and analyzed at 40x magnifications. Cross-sectional microhardness (CSMH) was carried out (50 g/5 s) at 25 µm, 50 µm, and 100 µm from the eroded surface and at 25 µm, 75 µm, and 125 µm from the enamel bond interface. Regarding microleakage, 7.5% of the samples showed no dye infiltration, 30% showed dye infiltration only at the enamel interface, and 62.5% showed dye infiltration through the dentin-enamel junction, with no difference between groups (p≥0.05). No significant difference was observed in CSMH at different depths (two-way ANOVA, p≥0.05). We did not observe significant changes in microleakage or CSMH after erosive/abrasive challenges in deciduous teeth treated with different adhesive protocols (etch-and-rinse and self-etching adhesives, with and without fluoride).


Asunto(s)
Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Cementos Dentales/química , Cementos de Resina/química , Erosión de los Dientes/etiología , Diente Primario/química , Análisis de Varianza , Esmalte Dental/química , Esmalte Dental/efectos de los fármacos , Filtración Dental/etiología , Dentina/química , Dentina/efectos de los fármacos , Fluoruros/química , Pruebas de Dureza , Humanos , Ensayo de Materiales , Distribución Aleatoria , Valores de Referencia , Reproducibilidad de los Resultados , Saliva Artificial/química , Estadísticas no Paramétricas , Propiedades de Superficie , Diente Primario/efectos de los fármacos
14.
J. appl. oral sci ; 26: e20170053, 2018. tab, graf
Artículo en Inglés | LILACS, BBO - Odontología | ID: biblio-893684

RESUMEN

ABSTRACT Objective: To evaluate the effect of erosive challenges on the tooth- restoration interface of deciduous teeth treated with different adhesive protocols. Material and Methods: Deciduous molars were cut mesiodistally, then embedded, abraded and polished (n=80). Samples were randomly divided according to the adhesive system used into: G1 (Adper Single Bond2®, etch-and-rinse), G2 (Universal Single Bond®, self-etching), G3 (OptibondFL®, etch-and-rinse with Fluoride) and G4 (BondForce®, self-etching with Fluoride). After standardized cavity preparation (2 mm diameter x 2 mm depth), adhesive systems were applied and samples were restored (composite resin Z350®). Half of the samples were exposed to erosive/abrasive cycles (n = 10, each adhesive group), and the other half (control group; n = 10) remained immersed in artificial saliva. For microleakage analysis, samples were submersed in methylene blue and analyzed at 40x magnifications. Cross-sectional microhardness (CSMH) was carried out (50 g/5 s) at 25 μm, 50 μm, and 100 μm from the eroded surface and at 25 μm, 75 μm, and 125 μm from the enamel bond interface. Results: Regarding microleakage, 7.5% of the samples showed no dye infiltration, 30% showed dye infiltration only at the enamel interface, and 62.5% showed dye infiltration through the dentin-enamel junction, with no difference between groups (p≥0.05). No significant difference was observed in CSMH at different depths (two-way ANOVA, p≥0.05). Conclusions: We did not observe significant changes in microleakage or CSMH after erosive/abrasive challenges in deciduous teeth treated with different adhesive protocols (etch-and-rinse and self-etching adhesives, with and without fluoride).


Asunto(s)
Humanos , Diente Primario/química , Erosión de los Dientes/etiología , Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Cementos de Resina/química , Cementos Dentales/química , Valores de Referencia , Saliva Artificial/química , Propiedades de Superficie , Diente Primario/efectos de los fármacos , Ensayo de Materiales , Distribución Aleatoria , Reproducibilidad de los Resultados , Análisis de Varianza , Estadísticas no Paramétricas , Esmalte Dental/efectos de los fármacos , Esmalte Dental/química , Filtración Dental/etiología , Dentina/efectos de los fármacos , Dentina/química , Fluoruros/química , Pruebas de Dureza
15.
Schizophr Bull ; 43(6): 1153-1157, 2017 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-28981868

RESUMEN

While previous studies have found evidence for detrimental effects of metals on neurodevelopment, the long-term effects on mental health remain unclear. The objective was to explore the effect of early metal exposure on risk of psychotic disorder and on symptom severity following illness onset. Through the use of validated tooth-biomarkers, we estimated pre- and postnatal exposure levels of essential elements (copper, magnesium, manganese, and zinc) and elements associated with neurotoxicity (lead, arsenic, lithium, and tin). We found consistently higher levels of lithium in patients compared to controls. Higher levels of magnesium and lower levels of zinc were associated with more severe psychopathology over 20 years after metal exposure. The results show promise for the use of teeth biomarkers in examining early environmental risk for psychosis and underscore the relevance of studying metal exposure during critical neurodevelopmental periods.


Asunto(s)
Exposición a Riesgos Ambientales , Litio/metabolismo , Magnesio/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Trastornos Psicóticos/metabolismo , Esquizofrenia/metabolismo , Diente Primario/química , Zinc/metabolismo , Adulto , Arsénico/metabolismo , Cobre/metabolismo , Femenino , Humanos , Plomo/metabolismo , Manganeso/metabolismo , Espectrometría de Masas , Embarazo , Estaño/metabolismo , Adulto Joven
16.
Environ Int ; 108: 299-308, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28941415

RESUMEN

BACKGROUND: Manganese (Mn) is an essential element required for growth and development, but higher body burdens have been associated with neurobehavioral decrements in children. OBJECTIVES: We examined whether prenatal or postnatal Mn measured in deciduous teeth was associated with scores on a test of visuospatial learning and memory. METHODS: Deciduous teeth were collected from 142 participants (ages 10-14years) residing near varied ferro­manganese industry in Italy. Mn concentrations were measured in prenatal and postnatal tooth regions by laser ablation inductively coupled plasma mass spectrometry (ICP-MS). The Virtual Radial Arm Maze (VRAM), an animal-human analogue task, was used to assess visuospatial learning and memory. We used generalized additive, linear and zero-inflated Poisson mixed regression models to estimate associations between prenatal or postnatal Mn concentrations and repeated measures of all four VRAM outcomes: time, distance, working and reference memory errors. Effect measure modification by sex was examined in stratified models. RESULTS: U-shaped associations between prenatal Mn and VRAM outcomes were observed among girls only (pGAMM=0.001 to 0.02 in stratified models). Compared to the mid-tertile of prenatal Mn, girls in the highest tertile took 7.7s [95% CI: -6.1, 21.5] longer to complete the task, traveled 2.3 maze units [0.1, 4.4] farther, and committed more working and reference memory errors (ß for count ratio=1.33 [1.01, 1.83]; 1.10 [0.98, 1.24], respectively). This association was not observed among boys. In contrast, for postnatal Mn, no significant associations were found, and patterns were similar for boys and girls. CONCLUSIONS: The prenatal period may be a critical window for the impact of environmental Mn on visuospatial ability and executive function, especially for females.


Asunto(s)
Manganeso/análisis , Diente Primario/química , Percepción Visual/efectos de los fármacos , Adolescente , Niño , Exposición a Riesgos Ambientales , Femenino , Humanos , Italia , Masculino , Manganeso/toxicidad , Memoria , Pruebas de Estado Mental y Demencia
17.
Proc Natl Acad Sci U S A ; 114(24): 6268-6273, 2017 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-28559355

RESUMEN

Weaning practices differ among great apes and likely diverged during the course of human evolution, but behavioral inference from the fossil record is hampered by a lack of unambiguous biomarkers. Here, we show that early-life dietary transitions are recorded in human deciduous tooth enamel as marked variations in Ca isotope ratios (δ44/42Ca). Using a sequential microsampling method along the enamel growth axis, we collected more than 150 enamel microsamples from 51 deciduous teeth of 12 different modern human individuals of known dietary histories, as well as nine enamel samples from permanent third molars. We measured and reconstructed the evolution of 44Ca/42Ca ratios in enamel from in utero development to first months of postnatal development. We show that the observed variations of δ44/42Ca record a transition from placental nutrition to an adult-like diet and that Ca isotopes reflect the duration of the breastfeeding period experienced by each infant. Typically, the δ44/42Ca values of individuals briefly or not breastfed show a systematic increase during the first 5-10 mo, whereas individuals with long breastfeeding histories display no measurable variation in δ44/42Ca of enamel formed during this time. The use of Ca isotope analysis in tooth enamel allows microsampling and offers an independent approach to tackle challenging questions related to past population dynamics and evolution of weaning practices in hominins.


Asunto(s)
Isótopos de Calcio/análisis , Esmalte Dental/química , Diente Primario/química , Destete , Animales , Dieta , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Leche/metabolismo , Leche Humana/metabolismo
18.
J Clin Pediatr Dent ; 40(6): 496-502, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27805893

RESUMEN

OBJECTIVE: Most cases of hypophosphatasia (HPP) exhibit early loss of primary teeth. Results of micro-computed tomography (micro-CT) analysis of teeth with HPP have not yet been reported. The purpose of the present study was to describe the size and mineral density distribution and mapping of exfoliated teeth with HPP using micro CT. STUDY DESIGN: Seven exfoliated teeth were obtained from a patient with HPP. Exfoliated teeth sizes were measured on micro CT images and mineral densities of the mandibular primary central incisors were determined. RESULTS: Partial dentures were fabricated for the patient to replace the eight primary teeth which had exfoliated. Most primary teeth sizes were within the normal range. The mean values of enamel and dentin mineral densities in teeth with HPP were 1.35 and 0.88 g/cm3, respectively, in the mandibular primary central incisors. CONCLUSION: Mineral density distribution and mapping revealed that the values in teeth with HPP were lower than the homonymous teeth controls in all regions from the crown to apex. Furthermore, it was demonstrated that the differences between HPP and controls were larger on the crown side and the differences tended to converge on the apex side. These results suggested that the present patient showed mild hypomineralization in the primary dentition.


Asunto(s)
Hipofosfatasia/patología , Calcificación de Dientes/fisiología , Diente Primario/patología , Esmalte Dental/patología , Dentina/patología , Humanos , Hipofosfatasia/metabolismo , Procesamiento de Imagen Asistido por Computador/métodos , Lactante , Masculino , Minerales/análisis , Odontometría/métodos , Cuello del Diente/patología , Corona del Diente/patología , Exfoliación Dental , Diente Primario/química , Microtomografía por Rayos X/métodos
19.
Environ Monit Assess ; 188(9): 505, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27491948

RESUMEN

In war zones, the explosion of bombs, bullets, and other ammunition releases multiple neurotoxicants into the environment. The Middle East is currently the site of heavy environmental disruption by massive bombardments. A very large number of US military bases, which release highly toxic environmental contaminants, have also been erected since 2003. Current knowledge supports the hypothesis that war-created pollution is a major cause of rising birth defects and cancers in Iraq. We created elemental bio-imaging of trace elements in deciduous teeth of children with birth defects from Iraq. Healthy and naturally shed teeth from Lebanon and Iran were also analyzed for trace elements. Lead (Pb) was highest in teeth from children with birth defects who donated their teeth from Basra, Iraq (mean 0.73-16.74 (208)Pb/(43)Ca ppm, n = 3). Pb in healthy Lebanese and Iranian teeth were 0.038-0.382 (208)Pb/(43)Ca ppm (n = 4) and 0.041-0.31 (208)Pb/(43)Ca ppm (n = 2), respectively. Our hypothesis that increased war activity coincides with increased metal levels in deciduous teeth is confirmed by this research. Lead levels were similar in Lebanese and Iranian deciduous teeth. Deciduous teeth from Iraqi children with birth defects had remarkably higher levels of Pb. Two Iraqi teeth had four times more Pb, and one tooth had as much as 50 times more Pb than samples from Lebanon and Iran.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminantes Ambientales/toxicidad , Metales Pesados/toxicidad , Efectos Tardíos de la Exposición Prenatal , Diente Primario/química , Guerra , Niño , Anomalías Congénitas/epidemiología , Anomalías Congénitas/metabolismo , Contaminantes Ambientales/análisis , Contaminantes Ambientales/farmacocinética , Femenino , Humanos , Metales Pesados/análisis , Metales Pesados/farmacocinética , Medio Oriente , Embarazo , Efectos Tardíos de la Exposición Prenatal/epidemiología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Diente Primario/efectos de los fármacos
20.
Nat Rev Endocrinol ; 12(7): 381-93, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27150289

RESUMEN

Paracetamol and NSAIDs, in particular acetylsalicylic acid (aspirin) and ibuprofen, are among the most used and environmentally released pharmaceutical drugs. The differences in international trends in the sale and consumption of mild analgesics reflect differences in marketing, governmental policies, habits, accessibility, disease patterns and the age distribution of each population. Biomonitoring indicates ubiquitous and high human exposure to paracetamol and to salicylic acid, which is the main metabolite of acetylsalicylic acid. Furthermore, evidence suggests that analgesics can have endocrine disruptive properties capable of altering animal and human reproductive function from fetal life to adulthood in both sexes. Medical and public awareness about these health concerns should be increased, particularly among pregnant women.


Asunto(s)
Analgésicos no Narcóticos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Disruptores Endocrinos/uso terapéutico , Dolor/tratamiento farmacológico , Resultado del Embarazo/epidemiología , Efectos Tardíos de la Exposición Prenatal/epidemiología , Anomalías Urogenitales/epidemiología , Acetaminofén/análisis , Acetaminofén/uso terapéutico , Analgésicos no Narcóticos/análisis , Antiinflamatorios no Esteroideos/análisis , Aspirina/análisis , Aspirina/uso terapéutico , Comercio/estadística & datos numéricos , Anomalías Congénitas/epidemiología , Monitoreo de Drogas , Exposición a Riesgos Ambientales , Femenino , Humanos , Ibuprofeno/uso terapéutico , Meconio/química , Leche Humana/química , Diente Molar/química , Manejo del Dolor , Embarazo , Ácido Salicílico/metabolismo , Diente Primario/química
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