Dissertations / Theses on the topic 'Enamel-A'
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1
McKee, Marc Douglas. "A morphological and functional investigation of the enamel organ and enamel in the rat incisor /." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75424.
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A morphological and functional investigation of the enamel organ and enamel was carried out on the incisor of the rat. Using transmission electron microscopy and other electron optical techniques, the ultrastructure of enamel hydroxyapatite crystallites and the morphology of the cells of the enamel organ related to these crystallites were examined. In the enamel secretion zone, putative cell communication via matched approaches of rough endoplasmic reticulum to the ameloblast cell membrane was not confirmed. Throughout the enamel organ, extracellular permeability was assessed using radiolabeled proteins as tracers. Regional differences were found, especially related to the two types of maturation ameloblasts. Several modified histochemical techniques were successfully applied to the enamel such that the functional contribution of each type of ameloblast was ascertained. In this way it was demonstrated that several functional cell subpopulations exist and that they can be correlated with different calcium and protein distributions within the enamel. In vivo injection of vinblastine, and in vitro treatments with other drugs, all severely modified the enamel maturation staining pattern and $ sp{45}$Ca uptake. In addition, it was found that ruffle-ended maturation zone ameloblasts possess higher levels of specific transferrin receptor sites relative to smooth-ended ameloblasts, a finding that may be directly related to the deposition of iron within the enamel.
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Hall, Nathan E. "A Radiographic Analysis of Variance in Lower Incisor Enamel Thickness." VCU Scholars Compass, 2005. http://scholarscompass.vcu.edu/etd/887.
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The purpose of this study was to help predict the enamel thickness of mandibular incisors. At least two direct digital periapical radiographs were made for each of the 80 subjects. Radiographs were scaled to control for magnification errors using dental study models and computer software. Mesiodistal incisor width and mesial and distal enamel thicknesses were measured. Lateral incisors were determined to be wider than central incisors and distal enamel thicknesses were larger than mesial enamel thicknesses on average. The African American group demonstrated wider incisors and enamel thicknesses than the Caucasian group on average. Enamel thickness positively correlated with tooth width for all incisors. No statistically significant differences were detected between male and female groups. Some conclusions relating to enamel thickness can be made based on race, incisor position, and incisor width, but correlations were not considered strong enough to accurately determine enamel width, without the aid of radiographs.
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Robinson, Bruce William. "A morphological study of the formation of the dentino-enamel junction in the rat molar : the role of dentin in enamel formation." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/27630.
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This thesis is a morphological study detailing the initial formation of the dentino-enamel junction (DEJ) in the rat molar. It was undertaken to determine how enamel apatite crystals are initiated during tooth development. The DEJ was investigated along its developmental gradient so that both the spatial and temporal sequences of dentin and enamel mineralization could be observed. For this investigation both conventional and selected-area dark-field electron microscopy were applied. The results of this study indicate that enamel crystals arise by epitaxial growth from preformed dentin crystals. This is supported by the temporal relationship beween dentin and enamel where dentin mineralization preceeds enamel mineralization and the intimate spatial relationship between the apatite crystals of dentin and enamel at both the newly formed and the more mature dentino-enamel junction. These results also suggest that the terminal portions of collagen fibrils in the pre-dentin matrix undergo some alteration prior to mineralization which may be related to their function in presenting dentin apatite to the enamel matrix. The interrelatonship between both the inorganic and organic matrices of dentin and enamel are presented in a working model and discussed in light of the mechanisms by which mineralized dentin may promote the formation of enamel crystals.Medicine, Faculty of
Graduate
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Moeinian, Malihe. "Development of a radiopaque infiltration resin for early enamel carious lesion." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/36694.
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A white spot lesion (WSL) is defined as enamel porosity, which could be due to an enamel defect or an initial carious lesion. ICON® resin is a resin infiltrant that penetrates into the enamel porosity and seals the lesion, thus inhibiting the progression of caries. This method is micro-invasive; however, the resin is radiolucent and the clinician cannot detect the material using radiographs. In order to develop a radiopaque resin, understanding the pore size and pore structure in WSLs is helpful. Therefore, the aim of this study was to characterise: (1) the pore size and structure, (2) the incorporation of radiopaque agents into ICON® resin. Brunauer-Emmett-Teller (BET) and focused ion beam-scanning electron microscopy (FIB-SEM) were used to characterise the porosity in WSLs. The data showed the enamel prisms become more pronounced in the advanced areas of the WSLs and demineralisation occurs within or/and between the enamel prisms. The pore size could be as small as an enamel crystallite, 28x48nm. Nano-strontium hydroxyapatite (non-coated and coated) and strontium bioglass were made as radiopaque fillers and characterised using different techniques including fourier transform infrared spectroscopy (FTIR), BET, transmission electron microscopy (TEM), X-ray diffraction (XRD) and particle size measurements. The radiopaque fillers had micron-sized particles, which made them unsuitable for infiltration into WSLs despite their possible ability to remineralise the WSLs. Radiopaque monomers including bromine-methacrylate and tin-methacrylate were able to make ICON® resin radiopaque and they showed a similar viscosity, wettability and biocompatibility compared to ICON® resin. The X-ray microtomography (XMT) showed that the experimental radiopaque resins were able to infiltrate into the WSLs, artificial and natural lesions, and they could be detected using image subtraction. Backscattered electron (BSE) imaging after each step of application of materials showed that the etching pattern and etchant gel could be barriers for a successful infiltration of the resins into WSLs.
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Abdellatif, Abeer Moustafa. "A study of developmental defects of enamel using clinical indices and image analysis." Thesis, University of Sheffield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247151.
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Al-Mosawi, Mohammed. "Towards a 4-D spatial and temporal model of human enamel biomineralisation." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/41764.
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Precise timings and spatial progression of human enamel biomineralisation are still largely unknown due to scarcity of developing human enamel specimens available for investigation. This information is crucial for optimising emerging biomimetic regenerative and reparative dentistry routes. Five developing permanent incisors were obtained from an archaeological source and used alongside mature contemporary teeth for comparison. X-ray microtomography (XMT), synchrotron X-ray diffraction (S-XRD) and quantitative back-scattered electrons (qBSE) imaging were used to investigate the mineral density distribution, the crystallites texture magnitude and orientation and the nanostructure of dental enamel at various developmental stages, respectively. XMT revealed that there was a bi-directional mineralisation "front" that starts at the cusp tip and at the enamel-dentine junction (EDJ) travelling cervically and peripherally until the relative mineral density is uniform in the fully mature tooth (2.75 g/cm3 ± 0.01 g/cm3). S-XRD revealed that within one probed region, two populations of crystallite orientations exist simultaneously with an angular separation of 20-50°, with one population being more dominant than the other by a factor of approximately 3:7. Furthermore, one population displayed a higher degree of crystallite texture than the other. These phenomena were observed in all stages of tooth development. The crystallites in both populations were oriented approximately perpendicular to the EDJ regardless of development stage, indicating initial preferred directions of crystallites persist from early through to full maturation. The direction and magnitude of organisation within two distinct populations of crystallites within the developing and mature enamel has not been quantified previously. qBSE analyses suggested that the two observed populations are most likely due to prism decussation and revealed that mineralisation of prism cores precedes that of prism boundaries. These results provide new insights towards building a quantitative spatio-temporal model of human enamel biomineralisation in order to inform emerging biomimetic reparative/regenerative dental technologies.
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Chatfield, Stuart R. "A study of pore structure of human dental enamel using radiotracer techniques." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389134.
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Al, Kawas Sausan. "A comparative study of maturation processes in enamel and bone in the rat." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ36951.pdf.
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Baxter, Richard Turner. "Using Digital Microscopy to Evaluate Enamel Defects in Young Children: A Novel Method." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1403188806.
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Bechtle, Sabine [Verfasser]. "On the mechanical properties of dental enamel - A multi-scale approach - / Sabine Bechtle." München : Verlag Dr. Hut, 2011. http://d-nb.info/1014848709/34.
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Elshami, Marrow. "Micro-leakage and Enamel demineralisation : a comparative study of three different adhesive cements." University of the Western Cape, 2016. http://hdl.handle.net/11394/5607.
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Magister Scientiae Dentium - MSc(Dent)Introduction: Micro-leakage and enamel demineralization is still a major challenge in dental practice. It can lead to formation of demineralization lesions around and beneath the adhesive–enamel interface (Mali et al., 2006). Enamel demineralization adjacent to orthodontic brackets is one of the risks associated with orthodontic treatment. The prevention of demineralization during orthodontic treatment is therefore essential for aesthetic reasons and to circumvent the onset of caries. Aim: To assess micro-leakage and enamel demineralization around orthodontic direct attachments (brackets) using three different orthodontic cements. Materials and methods: In this in-vitro study, intact (non carious) extracted human premolars were used to compare the micro-leakage and enamel demineralization of three different cements (Fuji Ortho LC, Rely X luting 2 and Transbond XT). The dye penetration technique was used to evaluate micro-leakage on extracted human premolars. Micro-hardness testing was performed on 21 teeth to determine enamel demineralization. Sixty teeth were randomly divided into 3 groups of twenty teeth each. Direct attachments were cemented on each tooth using 3 different cements; Fuji Ortho LC (GC Fuji II LC GC Corporation Tokyo, Japan), (group 1), Rely X luting 2 cement (3M ESPE dental product, USA), (group 2), Transbond XT Light Cure (3M Unitek, Monrovia, Calif), (group 3). After the orthodontic direct attachments were fitted, they were exposed to 500 thermo-cycles between 5°C and 55°C, with a dwell time of 15 seconds in a buffered (pH 7) 1% methylene blue dye solution (Grobler et al, 2007). The specimens were viewed under a stereomicroscope (Nikon, Japan) at magnification of 40 times. Photographs of each specimen were taken with a Leica camera (Leica DFC 290 micro-systems, Germany) fitted onto a stereomicroscope. The ACDsee photo editing programme was used to transfer the photographs to a computer to measure the dye penetration along the enamel–adhesive and adhesive–bracket interfaces, both on the gingival and occlusal edge at × 40 magnification. For the demineralization sample, 21 teeth were divided into 3 groups of seven teeth each, where direct attachments were cemented using each of the 3 cements, group 1, Fuji Ortho LC (GC Fuji II LC GC Corporation Tokyo, Japan); group 2, Rely X luting 2 cement (3M ESPE dental product, USA) and group 3, Transbond XT Light Cure (3M Unitek, Monrovia, Calif). A digital hardness tester with Vickers diamond indenter (Zwick RoellIndentec (ZHV; Indentec UK) was used to measure surface micro-hardness of enamel before and after attaching the brackets. Ten indentations were made on the enamel surface of each tooth before bonding the brackets with a 300g load applied for 15 seconds to establish the baseline hardness value. After de-bonding the brackets, the hardness was measured again in the same area as mentioned above to determine the degree of enamel demineralization (softening). Result: The result showed statistically significantly lower levels of micro-leakage for Transbond XT (P= <0.001). The amount of micro-leakage on the margins was significantly higher in the gingival portion (P <0.05) as compared with the occlusal margin. Enamel micro-hardness tests before bonding using the three different cements showed that the variances are not significantly different (Chi-squared = 3.051, df = 2, p-value = 0.218). However, the micro-hardness tests done after bonding and thermo-cycling was statistically significantly different (Chi-squared = 13.435, df = 2, p-value = 0.001). Clearly, the Transbond XT group had less hardness, implying greater demineralization than the Fuji Ortho LC and Rely X luting 2 groups. Two sample t-tests show that mean value for the Fuji Ortho and Rely X luting 2 were not significantly different from each other (t = -0.636, df = 12, p-value = 0.537). The mean value for Transbond XT differed significantly from both the other two means: Transbond XT vs Fuji Ortho LC (t = 3.249, df = 6.9, p-value = 0.014). Transbond XT vs Rely X luting 2 (t = 3.493, df = 6.8, p-value = 0.011). Conclusions: This study showed that Fuji Ortho LC and Rely X luting 2 show more micro-leakage than Transbond XT. However Transbond XT had significant lower micro-leakage, less hardness (greater demineralization) than the Fuji Ortho LC and Rely X luting 2. This may have been due to the fluoride release which significantly reduces demineralization. Therefore the Fuji Ortho LC and Rely X luting 2 may be recommended for prevention of demineralization during orthodontic treatment.
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Dobney, Keith Mark. "A modern epidemiological study of enamel hypoplasia : a putative model for the study of physiological stress in past human populations." Thesis, University of Bradford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261726.
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Prey, Ann. "Effectiveness of a professional bleaching product on the four shade ranges of teeth enamel." Menomonie, WI : University of Wisconsin--Stout, 2005. http://www.uwstout.edu/lib/thesis/2005/2005preya.pdf.
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Griggs, Henry G. "Potential iatrogenic effects on enamel treated with a light cured flouride releasing filled resin." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2008m/griggs.pdf.
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Laurance-Young, P. "Comparative physicochemical changes of human and bovine enamel following a short duration acid exposure." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1348488/.
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The principle aims of this work were two-fold: to investigate the effects of a short duration acid exposure on enamel and to evaluate the suitability of bovine material as a substitute for human enamel at these early stages. The former has largely been overlooked in the literature and has potential for clinical care and remineralisation strategies, while the latter has become an increasing issue manifesting as a lack of human research material neccessitating the substitution of an alternative species. Two models of erosion commonly employed in the literature were evaluated against each other. Greater bulk tissue loss was observed in the model with a repeated exposure of acid to enamel compared to the alternative single immersion model. Quantitative optical profilometry (OP) assessment of bulk tissue loss in both human and bovine enamel using 1 mol.L-1 acetic, citric and phosphoric acid solutions was not significant, a finding supported by alternative quantitative light fluorescence (QLF). This early data provided information regarding the expected shape of subsequent, more commercially applicable experimental data. The next series of experiments mirrored those mentioned previously but using commercially applicable 0.05% solutions. OP assessed bulk tissue loss was significantly different from that of 1 mol.L-1 solutions but direct comparison of the two species at 0.05% remained not significant. Both 1M and 0.05% acid solution datasets revealed a biphasic trend during the early erosion challenge. The erosion rate between 10-60 seconds was significantly different from the later 60-600 seconds, irrespective of acid type or species. Further analysis of the erosion lesions using atomic force microscopy (force vs distance measurements) suggested lesion morphology was more varied than previously thought. This led to an examination of lesion ultrastructure using micro-computed tomography and confocal microscopy. Potential subsurface softening was observed, together with areas of apparent acid resistance standing proud of the lesion base. The latter were probed using EDX, AFM and focussed-ion beam SEM, which confirmed the uneroded nature of these resistant areas. As far as we are aware, this is the first time such erosion trends and morphology have been reported.
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McGeouch-Flaherty, Carrie-Anne. "Proton assisted dissolution of the dental hard tissue enamel as a non-bacterial process." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/49476/.
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The overall aim of this thesis was to examine the kinetics of proton-promoted dissolution of the dental hard tissue enamel as a non-bacterial process and the evaluation of inhibitors with the intent of minimising the dissolution process and effectively protecting the surface. A novel approach was taken, utilising scanning electrochemical microscopy (SECM) to galvanostatically generate controllable and well defined proton fluxes in defined areas of the surface. The resulting etch pits formed on the surface were characterised by optical microscopy and white light interferometry (WLI), which quantitatively determined etch pit dimensions. A theoretical finite element model (FEM) was used to elucidate the kinetics of dissolution based upon the analysis of the shape and dimensions of etch pits produced. A heterogeneous rate constant of dissolution of 0.08 ± 0.04 cm s-1 was attributed to untreated enamel, whereas 2 min treatment with 1000 ppm sodium fluoride (NaF) decreased this rate constant slightly to 0.05 ± 0.03 cm s-1. The impact of fluoride on the rate of proton attack was evident from the formation of shallower broader etch pits. In relation to both acid erosion and caries, the two most relevant acids pertinent to enamel dissolution are citric acid and lactic acid. These acids were investigated by protonating their respective sodium salts in-situ to produce localised weak acid directly under the probe tip. This permitted the surrounding enamel sample to remain largely unaltered giving a true surface for comparison, whilst allowing evaluation of the kinetics in the presence of each weak acid. Etching in the presence of lactic acid, showed a surface controlled process with a rate constant of 0.1 ± 0.03 cm s-1. Etching in the presence of the triprotic citric acid, also yielded a surface controlled process with a rate constant of 0.35 ± 2.6 cm s-1. Calcite was also investigated using SECM, WLI and FEM to validate the use of these techniques. The kinetic data extrapolated was comparable to rate constants found in literature, confirming the validity of these methods. In this case, a novel approach was the use of experimental data to parameterise the finite element model directly. Confocal laser scanning microscopy (CLSM) coupled with SECM was used to visualise proton fluxes from the tip of the UME. This allowed, not only, correlation of the current applied to the probe tip with the pH, but also quantitative data on the spread of protons across a particular surface. Rate constants found for untreated and fluoride-treated enamel were comparable to those found in SECM etching, however, zinc ion treatment proved to result in much greater inhibition of dissolution than fluoride.
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Turkington, Marie. "Development of a sputter deposited calcium phosphate thin film for use as a model dental enamel surface." Thesis, University of Ulster, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400855.
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Shim, Hun DMD. "Systemic Conditions and Developmental Defects of Enamel in a Cohort of VLBW and NBW Infants." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1465487090.
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Allen, James Henry. "A comparison of the enamel demineralization inhibition and shear bond strength of two orthodontic resins." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2009m/allen.pdf.
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Barbour, Michele Emily. "Human tooth enamel dissolution in citric acid as a function of degree of saturation and pH." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272036.
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Easterly, Danielle E. "An Investigation of Surface Characteristics of Enamel Treated with Infiltrative Resin: A Scanning Electron Microscopy Study." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4764.
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AN INVESTIGATION OF SURFACE CHARACTERISTICS OF ENAMEL TREATED WITH INFILTRATIVE RESIN: A SCANNING ELECTRON MICROSCOPY STUDY
Danielle E. Easterly, Doctorate of Dental Surgery.
A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Dentistry at Virginia Commonwealth University.
Virginia Commonwealth University. 2017.
Director: Dr. Eser Tüfekçi
D.D.S., M.S., Ph.D., M.S.H.A.
Objective: To evaluate the microstructural changes of a resin infiltrant (ICON®, DMG America LLC, Englewood, NJ) after six months of simulated toothbrushing.
Materials and Methods: Ten extracted third molars (n=10) were collected. Artificial white spot lesions were created and resin applied. Environmental SEM images at 250X and 500X were taken after application of Icon® (T1), and after six months of simulated toothbrushing (T2). Micrographs were evaluated for changes in surface characteristics.
Results: SEM showed some changes in the surface characteristics of the resin after simulated toothbrushing. However, changes in presence of enamel rods, microcracks, or fractures were not statistically significant (p>0.05). The effects of polymerization shrinkage were noted on most samples in the form of clefts and fissures.
Conclusions: Icon® resin seems to withstand challenge by toothbrush abrasion over a six-month period, with some evidence of microstructural wear.
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Dawson, Leslie. "The health impact of climate change at Tell Leilan, a multi-level analysis of developmental enamel defects." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ46970.pdf.
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Upex, Bethan Rosemary. "Enamel hypoplasia in modern and archaeological caprine populations : the development and application of a new methodological approach." Thesis, Durham University, 2009. http://etheses.dur.ac.uk/182/.
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Archaeological research into domestic animals has demonstrated that enamel hypoplasia is a potentially valuable tool for investigating a range of archaeological topics including domestication and animal management strategies. However, research into archaeological domestic populations has been hindered by the difficulty of recording and interpreting enamel hypoplasia in high-crowned species such as caprines and cattle. This research develops a methodological approach for recording enamel hypoplasia in high-crowned species which is applied to modern and archaeological caprine populations from three geographically distinct regions (Orkney, Kenya and Iceland). Modern caprines with known life histories are used to investigate baseline factors such as the impact of the environment and nutrition on the frequency and severity of enamel hypoplasia in caprines. These baselines are then used to interpret enamel hypoplasia in archaeological populations. Results indicate that enamel hypoplasia frequency and severity can be linked to variation in the climate /environment as well as nutrition levels in caprine populations. By comparing enamel hypoplasia frequency and severity between populations with similar baseline factors, variation in animal management strategies can be identified. Physiological and seasonal stress events including birth, weaning, and seasonal periods of malnutrition are also identified using enamel hypoplasia in both modern and archaeological populations.
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Branco, Luciana Azevedo de Sá Rio. "Isotope analysis of dental enamel for assessing geographic origin and geographic mobility in humans: a pilot study." Master's thesis, Faculdade de Medicina da Universidade do Porto, 2011. http://hdl.handle.net/10216/63772.
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Henderson, Rowena Claire. "Early life histories : a study of past childhood diet and health using stable isotopes and enamel hypoplasia." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:a0ef07c7-7103-4a15-b825-0eae3e796882.
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The δδ13C and δ15N composition of incremental segments of tooth dentine was used to infer infant and childhood diet in a post-medieval London population, and a hunting and gathering Mesolithic/Neolithic group from Latvia. Health was analysed using defects on the tooth enamel caused by stress, termed enamel hypoplasia. The populations, which differ markedly in their economy, diet and health, were selected because of the difference in childhood experiences between the two groups. The results were used to consider questions about childhood, including how early diet may have been influenced by social factors such as class or status, the effect this could have on population dynamics and how childhood diet and health are related. The results show that the London individuals were rarely breastfed beyond 6 months and in some instances not at all. A small isotopic difference between males and females was observed which could be caused by dietary or physiological differences. The peak incidence of hypoplasia may be related to developmental patterns, rather than stress caused by weaning. The Zvejnieki individuals had a slightly longer breastfeeding duration. Those buried with pendants consumed a different diet in childhood to those without pendants, suggesting a complex social system, possibly indicating that diet was related to the role a person had within the community. There is a suggestion diet may have shifted between the Middle Mesolithic and Late Neolithic, although not dramatically. Neither population have elevated δ13C often associated with breastfeeding. The early life histories of the groups are not compared directly, but general observations concerning the children’s lives are considered. It is concluded that economy is not a reliable predictor of infant feeding strategies, as hunter-gatherers provide children with solid foods at a similar time to industrial groups. Intra-population variability was found to be a feature of all socio-economic groups.
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Karagianna, Anthoula. "Changes in the surface chemistry of enamel exposed to acid : a surface study of caries and erosion." Thesis, University of Leeds, 2012. http://etheses.whiterose.ac.uk/3237/.
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Dental caries is a result of acid production by plaque bacteria and manifests with mineral loss and hard tissue dissolution. Dental erosion is the irreversible loss of dental hard tissue caused by acidic agents without bacterial involvement. Numerous techniques have been described for the early detection of dental caries and erosion. However, they all rely on detecting already lost tissue, suggesting that the disease process has been operating for some time. Recent research suggests that uptake of protons from bacterial or dietary acids precedes hard tissue dissolution. The aim of this research project was to examine whether protonation of sound and carious sterile and non-sterile human primary tooth surfaces which have been subjected to acids of known pH occurs and can be detected in vitro and in situ with a simple and clinically applicable technique. A total of 219 human primary tooth surfaces were investigated in vitro. Of these, 110 sound and carious sterile and non-sterile tooth surfaces were examined at baseline and 109 after an acidic challenge. Universal pH indicator solution was used to assess the protonation state of the tooth surfaces. Significantly more tooth surfaces were found protonated after the acidic challenge compared to baseline for all the groups of teeth (p<0.01) with the exception of non-sterile tooth surfaces with caries into dentine (p=0.467). This was probably because the tooth surfaces were already protonated at baseline as a result of the carious process. The in situ study involved five participants and thirty sound enamel slabs. The enamel slabs were obtained from human primary teeth and were incorporated into mandibular removable appliances. The appliances were placed intra-orally for 48 hours to allow plaque accumulation. After removal from the mouth, the enamel slabs were subjected to 10% w/v sucrose rinse. The protonation state of the tooth surface was assessed with universal pH indicator solution. The proportion of protonated tooth surfaces was significantly higher compared to the proportion of non-protonated tooth surfaces (p<0.001). The results of these studies suggest that protonation of human primary tooth surfaces after an acidic challenge occurs and can be detected with a clinically applicable technique both in vitro and in situ. Measuring the degree of protonation can be a novel means to detect tooth surfaces that are at increased risk of caries and erosion at a very early stage before any irreversible change of the hard tissue structure.
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Branco, Luciana Azevedo de Sá Rio. "Isotope analysis of dental enamel for assessing geographic origin and geographic mobility in humans: a pilot study." Dissertação, Faculdade de Medicina da Universidade do Porto, 2011. http://hdl.handle.net/10216/63772.
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Kendzior, Bradley F. "A comparison of the effects of different wavelengths of argon laser irradiation on the solubility of human enamel an in vitro study /." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1918.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains viii, 97 p. : ill. Includes abstract. Includes bibliographical references (p. 75-83).
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Choi, Yuen-ling Ruth. "The prevalence of enamel defects in Hong Kong Children in 1983 and 1991 a thesis submitted to the University of Hong Kong in partial fulfilment of the requirements for the degree of Master of Dental Surgery /." Click to view the E-thesis via HKUTO, 1993. http://sunzi.lib.hku.hk/HKUTO/record/B38628508.
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蔡苑玲 and Yuen-ling Ruth Choi. "The prevalence of enamel defects in Hong Kong Children in 1983 and 1991: a thesis submitted to the University ofHong Kong in partial fulfilment of the requirements for the degree ofMaster of Dental Surgery." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1993. http://hub.hku.hk/bib/B38628508.
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Wright, Carrie Carlota. "Calcium isotopes in sheep dental enamel : a new approach to studying weaning and dairying in the archaeological record." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:6f7d5179-594a-41c3-a06d-478a811b818a.
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Calcium isotope ratios (44Ca/42Ca) have shown promise as a milk dietary tracer. Previous studies have focused on bone but, due to homeostatic processes, δ44/42Ca values are highly variable. This has greatly complicated the identification of mammal milk consumption through bone analysis, resulting in a search for an alternative. This thesis describes controlled studies to assess the effects of milk consumption on δ44/42Ca values in bulk and sequential samples of dental enamel, using modern samples from Yorkshire, England, the Isle of Hoy, Scotland, and archaeological samples from Abu Hureyra, Syria. The samples from Yorkshire consisted of dental enamel, ewe milk, feed and bone. Dental enamel was sampled from the Hoy sheep. Milk and plants are the greatest contributors of calcium in the mammal diet. Feed and ewe milk samples confirmed that milk has lower δ44/42Ca values than plants in the diet, and with a common diet between ewes, uniform milk δ44/42Ca values are produced. Also, there is a significant difference between bulk molar enamel δ44/42Ca values between males and females, with males having higher values. Additionally, analysis of bulk and sequential samples of Hoy mature sheep molar enamel, although mass fractionation effects were small, produced δ44/42Ca values with a clear isotopic offset between the enamel likely formed during nursing, weaning and the full conversion to a plant diet. The δ44/42Ca values, once associated with dental development chronologies, led to the identification of a clear pattern of nursing and weaning in the enamel of the first and second molars of sheep with known dietary and weaning histories. The modern results were used to identify patterns of ancient nursing and weaning. Although evidence was insufficient to establish early weaning of the Abu Hureyra sheep, this research successfully established the potential of this approach for investigating milk production and consumption in the archaeological record.
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DeSantis, Lauren C. "Options for Treating Teeth Affected with Developmental Defects of Enamel A survey of dentists and dental hygienists in Ohio." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1431075856.
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O'Hara, Mackie C. "Investigating the regularity of linear enamel hypoplasia in Bornean and Sumatran orangutans and in a primate community from Sabah, Borneo." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461162720.
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Antoine, Daniel. "Evaluating the periodicity of incremental structures in dental enamel as a means of studying growth in children from past human populations." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394732.
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Tschoppe, Peter [Verfasser]. "Development of a remineralizing saliva substitute and effects of various saliva substitutes in combination with fluorides on enamel and dentin / Peter Tschoppe." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2011. http://d-nb.info/1026265487/34.
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Hojabri, Niloofar [Verfasser], and Karl-Heinz [Akademischer Betreuer] Kunzelmann. "Evaluation of the whitening effect of a mixture of self-assembling peptide and hydroxyapatite on bovine enamel / Niloofar Hojabri ; Betreuer: Karl-Heinz Kunzelmann." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2020. http://d-nb.info/1227188145/34.
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Mahal, Raj-Deep Singh. "A standardized approach to determine the effect of thermocycling and long term storage on the shear bond strength of orthodontic brackets cemented to bovine enamel." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0021/MQ53415.pdf.
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Mujica, Marcela. "Comparing tooth enamel disturbances in a pediatric population that had received prior chemotherapy treatment to age-matched controls from the Virginia Commonwealth University Pediatric Dentistry Clinic." VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3353.
Full textAbstract:
Purpose: The purpose of this study was to test whether children who have undergone cancer chemotherapy have a higher prevalence of enamel abnormalities of the second mandibular premolars than age matched controls. Methods: This study was a case-control design where the case group involved 26 subjects that had received chemotherapy treatment between the ages of 2 to 6 and at the time of the study were between the ages of 9 to 18. The control group consisted of 26 subjects matched for age and sex to the case group that had not received chemotherapy. The second mandibular premolars were assessed based on the types of defects, their number and location according to a modified DDE index. A secondary examiner, blinded to the results of the primary, analyzed photographs taken at examination and provided their own assessment in order to calibrate results. Result: Nominally there were more normal surfaces in the case group than in the control group (81% vs 70%) and fewer hypoplasias in the case group (5% vs 13%). There was no statistical difference between the buccal and occlusal surfaces. For the buccal surfaces, the cases were nominally lower but not statistically significant (P=0.0680) and there is no evidence for a case-control difference on the lingual surfaces (P>0.9). Conclusions: In this study developmental defects of the enamel organ were not observed to be statistically different between the case and control groups, although previous studies have shown otherwise.
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Rebele, Stephan F. [Verfasser], and Markus [Akademischer Betreuer] Hürzeler. "Tunnel technique with connective tissue graft versus coronally advanced flap with enamel matrix derivative for root coverage : a randomized controlled clinical trial using 3D digital measuring methods." Freiburg : Universität, 2015. http://d-nb.info/1119805813/34.
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Wang, Linda, Leslie Casas-Apayco, Ana Carolina Hipólito, Vanessa Manzini Dreibi, Marina Ciccone Giacomini, Júnior Odair Bim, Daniela Rios, and Ana Carolina Magalhães. "Effect of simulated intraoral erosion and/or abrasion effects on etch-and-rinse bonding to enamel." American Journal of Dentistry, 2014. http://hdl.handle.net/10757/612019.
Full textAbstract:
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por
restricciones de la casa editorial donde ha sido publicado.PURPOSE: To assess the influence of simulated oral erosive/abrasive challenges on the bond strength of an etch-and-rinse two-step bonding system to enamel using an in situ/ex vivo protocol. METHODS: Bovine enamel blocks were prepared and randomly assigned to four groups: CONT - control (no challenge), ABR - 3x/day-1 minute toothbrushing; ERO - 3x/day - 5 minutes extraoral immersion into regular Coca Cola; and ERO+ABR - erosive protocol followed by a 1-minute toothbrushing. Eight blocks were placed into an acrylic palatal appliance for each volunteer (n = 13), who wore the appliance for 5 days. Two blocks were subjected to each of the four challenges. Subsequently, all the blocks were washed with tap water and Adper Single Bond 2/Filtek Z350 were placed. After 24 hours, 1 mm2 beams were obtained from each block to be tested with the microtensile bond strength test (50 N load at 0.5 mm/minute). The data were statistically analyzed by one-way RM-ANOVA and Tukey's tests (alpha = 0.05). RESULTS: No difference was detected among the ABR, ERO, and CONT groups (P > 0.05). ERO+ABR group yielded lower bond strengths than either the ABR and ERO groups (P < 0.0113).
Revisión por pares
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Pini, Núbia Inocencya Pavesi 1987. "In vitro and in situ evaluation of microabrasion technique on enamel microhardness and morphology = Avaliação in vitro e in situ da técnica de microabrasão sobre a microdureza e morfologia do esmalte dental." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290365.
Full textAbstract:
Orientadores: José Roberto Lovadino, Débora Alves Nunes Leite LimaTexto em português e inglês
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Objetivo: Avaliar, in vitro, a influência dos ácidos utilizados para microabrasão e, in situ, o efeito do tempo de contato com a saliva na microdureza e morfologia do esmalte abrasionado. Metodologia: In vitro: Setenta blocos dentais bovinos foram divididos em 7 grupos (n=10). Os grupos experimentais foram tratados com aplicação ativa/passiva dos ácidos H3PO4 35% (E1/E2) ou HCl 6,6% (E3/E4); e controles, tratados com microabrasão com H3PO4+pedra-pomes (C5), HCl+silica (C6) ou nenhum tratamento (C7). In situ: Nove grupos (n=19) de blocos dentais bovinos foram divididos de acordo com o tratamento e o tempo de exposição salivar, sendo 4 grupos tratados com H3PO4+pedra-pomes, 4 com HCl+sílica e 1 grupo controle. Os grupos tratados foram subdivididos em: sem exposição salivar, 1 hora, 24 horas ou 7 dias de exposição em ambiente intrabucal. A microdureza superficial (SMH) foi avaliada antes e após a microabrasão, e após exposição salivar (in situ). A microdureza subsuperficial (CSMH - 10, 25, 50 e 75 ?m) foi analisada após a microabrasão (in vitro) e após a exposição salivar (in situ). Espécimes representativos foram selecionados para a avaliação da morfologia do esmalte por meio da microscopia confocal de varredura a laser (MCVL - in vitro) e por microscopia eletrônica de varredura (MEV - in situ). Para a análise estatística foi realizada análise de variância para medidas repetidas (Proc Mixed), e os testes de Tukey-Kramer e Dunnet (SMH) e ANOVA (parcelas subdivididas) e Tukey-Kramer (CSMH - in situ) (p<0.05). Resultados: In vitro: Não foram encontradas diferenças entre as análises pré e pós-microabrasão entre os grupos controles para SMH. Entre os grupos experimentais, a aplicação ativa demonstrou os maiores valores de SMH, sem diferença entre os ácidos, com a mesma forma de aplicação. A maioria dos grupos apresentou redução do valor de CSMH conforme aumento da profundidade, com diferenças entre os grupos com microabrasão (C5 e C6) e o C7; e entre todos os grupos experimentais e o C7. Comparando a aplicação dos ácidos, a aplicação ativa do H3PO4 (E1) mostrou maior CSMH com diferença estatística em relação ao HCl (E3). A MCVL demonstrou diferentes padrões de condicionamento para cada grupo. In situ: Para as análises de SMH, todos os grupos tratados apresentaram redução na microdureza, com diferenças em relação ao controle e a leitura inicial. Após exposição salivar, os resultados demonstraram que o tratamento com HCl+sílica foi mais propenso à remineralização, já que, com 1 hora foi verificado aumento na SMH, com diferença significante em relação à análise pós-microabrasão. Apenas o tratamento com HCl+sílica foi eficiente em reestabelecer tal propriedade em relação ao controle. A análise de CSMH confirmou a maior capacidade de remineralização do esmalte tratado com HCl+sílica, uma vez que após 7 dias de exposição salivar, os valores de microdureza foram restabelecidos para as camadas mais superficiais do esmalte (10 e 25 ?m). A MEV demonstrou o efeito remineralizador da saliva para ambos os tratamentos. Conclusões: Os ácidos utilizados para microabrasão apresentaram alto poder erosivo quando aplicados individualmente. O tratamento com HCl+sílica resultou em uma superfície de esmalte mais propensa à remineralização
Abstract: Objective: To evaluate, in vitro, the effect of acids used in microabrasion on enamel microhardness, and, in situ, the effects of remineralizing time on enamel surface after microabrasion. Methods: In vitro: Seven groups (n=10) of enamel blocks from bovine incisors were divided in: Experimental groups treated by active/passive application of 35% H3PO4 (E1/E2) or 6.6% HCl (E3/E4); and control groups treated by microabrasion with H3PO4+pumice (C5), HCl+silica (C6), or no treatment (C7). In situ: Nine groups (n=19) of same specimens were divided in according to microabrasion and salivary exposition being 1 control (no treatment) and 4 groups with microabrasion using 35% H3PO4+pumice and 4 groups using 6.6% +silica. One group of each treatment was submitted to 4 frames of salivary exposition, being without exposition and with 1 hour, 24 hours or 7 days of presence on in situ regimen. Surface microhardness (SMH) was evaluated before and after microabrasion, and after salivary exposition (in situ). Cross-sectional microhardness (CSMH) was analyzed after microabrasion (in vitro) and after salivary exposition (in situ). For confocal laser scanning microscopy (CLSM - in vitro) and scanning electron microscopy (SEM - in situ), representative specimens group were selected. Statistical analysis used Proc Mixed, Tukey-Kramer and Dunnet tests (SMH) e ANOVA (subdivided parcels) and Tukey-Kramer tests (CSMH - in situ) (p<0.05). Results: In vitro: For SMH, it was not found statistically differences between the control groups after treatment. Active application resulted in significantly higher microhardness results than passive application, with no difference between acids. For most groups, the CSMH decreased as the depth increased, with differences between the groups treated with microabrasion (C5 and C6) and C7; and between all of experimental groups and C7. A significantly higher mean CSMH result was obtained with active application of H3PO4 compared to HCl. CLSM revealed the conditioning pattern for each group. In situ: For SMH, the groups treated with microabrasion presented reducing in mineral content, with statistical difference in relation to the control and to the initial analysis. The treatment HCl+silica presented lower reduction and were statistically different from the treatment with H3PO4+pumice. After salivary exposition SMH results revealed that surface treated with HCl+silica was more prone to remineralizing effect of saliva, once it was verified since with 1 hour of presence in in situ regimen, with significant differences between the treatments after 7 days of salivary exposition. Just for SMH, the HCl+silica reached values obtained in control group. CSMH analysis showed that 7 days of salivary exposition were efficient in reestablish de values for the outer layers (10 e 25 ?m) of enamel treated with HCl+silica. SEM analysis presented the remineralizing effect in the course of the time. Conclusions: Acids used for enamel microabrasion presented a higher erosive action when solely applicated. Data suggested that enamel surface treated with HCl+silica presented more susceptibility for remineralizing action of saliva than that treated with phosphoric acid and pumice
Mestrado
Dentística
Mestra em Clínica Odontológica
42
Públio, Juliana do Carmo 1984. "The influence of enamel thickness and prior application of a desensitizing agent on dental bleaching efficacy = Influência da espessura do esmalte e da aplicação prévia de agente dessensibilizante na eficácia do clareamento dental." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290660.
Full textAbstract:
Orientadores: Débora Alves Nunes Leite Lima, Luis Alexandre Maffei Sartini PaulilloDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo deste estudo foi avaliar a influência da espessura do esmalte e a aplicação prévia de dessensibilizante na eficácia do tratamento clareador. O trabalho foi dividido em 2 estudos. No primeiro estudo foi testada a influência da espessura do esmalte (0,5mm de espessura, 1,0mm de espessura planificada, 1,0mm de espessura não planificada e sem esmalte- controle) na eficácia do clareamento em profundidade, variando-se o tipo de agente clareador, peróxido de carbamida (PC) 10% e peróxido de hidrogênio (PH) 35%. No segundo estudo foi avaliada a influência da aplicação prévia de agente dessensibilizante, fluoreto de sódio 2% e nitrato de potássio 5% associado ao fluoreto de sódio 2% e, sem agente dessensibilizante (controle) na eficácia do clareamento dental com PH35%. Nos dois estudos foram usados fragmentos dentais bovinos, pigmentados por chá preto, e distribuídos por esquema inteiramente casual no primeiro estudo e aleatório por sorteio no segundo estudo (n=10) em grupos de acordo com os tratamentos acima. As amostras foram armazenadas em saliva artificial durante as 3 semanas de tratamento. As leituras de cor da dentina oposta (1,75mm de espessura) do estudo 1 e as leituras de cor do esmalte (1,0mm de espessura) e dentina oposta (1,75mm de espessura) do estudo 2 foram realizadas após o manchamento (baseline) e após cada semana de tratamento clareador, utilizando o método CIE Lab através de espectrofotômetro (Konica Minolta CM 700 d, Japan). Para o estudo 1 os valores de ?E, ?L, ?a e ?b datados foram submetidos à análise de variância ANOVA em esquema fatorial e teste de Tukey (?=0,05). Para o estudo 2, a coordenada L* datada (L=100 - lightness; L=0 - darkness) foi submetida por meio de análise de medidas repetidas PROC MIXED e teste de Tukey-Kramer e os valores de ?E datados foram submetidos à análise de variância ANOVA e teste de Tukey (?=0,05). O esmalte de 2 amostras de cada grupo do estudo 2 foi observado em microscopia eletrônica de varredura (MEV). Nos resultados destes estudos pode-se observar que o clareamento com PC10% foi mais efetivo que o PH35% em profundidade dentinária para todos os parâmetros de delta, com exceção no terceiro tempo dos deltas. A presença da camada aprismática no esmalte interferiu na eficácia do PC10% somente no primeiro tempo de clareamento em ?E1, ?L1 e ?b1, entretanto não interferiu nos tempos de clareamento testado com PH35% (estudo 1). Ainda, o uso de agente dessensibilizante realizado previamente ao clareamento dental não interferiu no mecanismo de ação do PH35% em profundidade (estudo 2)
Abstract: The aim of this study was to evaluate the influence of enamel thickness and prior application of a desensitizing agent on the effectiveness of bleaching treatment. This project was divided into two studies. Firstly, we tested the influence of enamel thickness (0.5 mm thick, 1.0 mm planned thick, 1.0 mm unplanned thick and absence of enamel - control) on the effectiveness of bleaching, in-depth, according to the type of bleaching agent, as follows: 10% carbamide peroxide and 35% hydrogen peroxide. Secondly, we evaluated the influence of prior application of a desensitizing agent (potassium nitrate associated with 2% sodium fluoride, 2% neutral fluoride, or with no desensitizing agent - control) on the effectiveness of tooth bleaching by using 35% hydrogen peroxide. In both studies we used bovine teeth fragments, stained with black tea, which were allocated into groups according to the aforementioned treatments, by an entirely causal scheme for the first study and by random drawing for the second one (n=10). The specimens were stored in artificial saliva during the 3-week-treatment. Color readings of the underlying dentin (1.75 mm thick) concerning the study 1, and color readings of enamel (1.0 mm thick) and underlying dentin (1.75 mm thick) of the study 2, were performed after staining (baseline) and after each week of bleaching treatment using the CIE Lab method by means of spectrophotometer (Konica Minolta CM 700d, Japan). For the study 1, the values of ?E, ?L, ?a and ?b recorded were subjected to factorial analysis of variance (ANOVA) and Tukey's test (? = 0.05). For the study 2, the coordinate L* recorded (L = 100 - lightness, L = 0 - darkness) was submitted to analysis of repeated measures PROC MIXED and Tukey-Kramer's test, and the ? values registered underwent analysis of variance (ANOVA) and Tukey's test (? = 0.05). The enamel of 2 specimens from each group of the study 2 was observed under scanning electron microscopy. According to the findings, it could be observed that the bleaching with 10% CP was more effective than that with 35% PH as regards dentin depth for all parameters delta, except the third time deltas. The presence of the prismless layer of enamel interfered with the effectiveness of 10% CP just in the first time of bleaching in ?E1, ?L1and ?b1, however it did not affect the times of bleaching when 35% HP was tested (study 1). In addition, the use of a desensitizing agent prior to tooth bleaching did not interfere with the mechanism of action of the 35% hydrogen peroxide concerning tooth depth (study 2)
Mestrado
Dentística
Mestra em Clínica Odontológica
43
Carvalho, Ariany Borges 1987. "Effects of repeated CO2 laser applications on primary enamel demineralization = An in vitro study = Efeito de aplicações repetidas de laser de CO2 sobre a desmineralização no esmalte de dentes decíduos: estudo in vitro." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288102.
Full textAbstract:
Orientador: Marinês Nobre dos Santos UchôaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Estudos prévios mostraram que uma irradiação do esmalte dentário com uma aplicação do laser de dióxido de carbono (CO2) modifica a superfície desse substrato e traz benefícios no que concerne ao aumento na resistência aos ácidos, diante os desafios cariogênicos. No entanto, ainda não se sabe se a irradiação repetida do esmalte decíduo com o laser de CO2 promoveria efeitos adicionais na resistência à desmineralização do esmalte. Assim sendo, este estudo teve como objetivo verificar, in vitro, se o acúmulo de irradiações do esmalte decíduo com laser de CO2, com comprimento de onda 10,6 ?m e densidade de energia de 20,0 J/cm2 seriam capazes de aumentar a inibição da perda mineral do esmalte decíduo, quando submetido às situações de alto desafio cariogênico. Para isto, 80 espécimes de esmalte hígido de molares decíduos foram selecionados após análise pontual prévia de Ca pela Espectrometria de Fluorescência de Raio-X (?-EDXRF) e aleatoriamente divididos em 4 grupos: controle (C), 1 aplicação do laser de CO2 (L1), 2 aplicações do laser de CO2 (L2) e 3 aplicações do laser de CO2 (L3). Os espécimes foram submetidos à análise da área de Ca por meio do ?-EDXRF antes da aplicação de laser e após a ciclagem de pH. Depois, foram divididos para serem analisados por Microdureza e Microscopia Eletrônica de Varredura (MEV). Os resultados foram analisados por ANOVA seguida de teste t, teste de Kruskal-Wallis, test t pareado e regressão linear simples (p<0,05). Em relação à microdureza, todas as condições de irradiação foram significativamente efetivas em reduzir a perda mineral quando comparadas ao grupo controle (p<0,01), não havendo diferenças entre os grupos L1 e L2. Entre os grupos irradiados, o grupo L3 apresentou os maiores resultados de redução de perda mineral (p<0,01). Os resultados da análise final do ?-EDXRF mostraram que somente o grupo L1 apresentou uma porcentagem significativamente menor de Ca quando comparado com outros grupos e o test t pareado mostrou que houve um aumento de Ca após a ciclagem de pH no grupo L2 (p=0,046). Os resultados da MEV mostraram fusão e derretimento na superfície de esmalte irradiada. Assim, três aplicações repetidas sobre o esmalte de dentes decíduos com o laser de CO2, nas condições empregadas no estudo, aumentaram significativamente a inibição de desmineralização do esmalte
Abstract: Previous studies have shown that one single irradiation of primary dental enamel with carbon dioxide (CO2) laser promotes ultrastructural crystallographic effects on enamel surface and turns it more acid-resistance under a cariogenic challenge. However, the effects of repeated applications of CO2 laser irradiation on the inhibition of demineralization in primary enamel have not been investigated. Thus, the aim of this study was to investigate, in vitro, if the repeated application of CO2 laser irradiation on the primary enamel with a wavelength of 10.6 ?m and density of 20.0 J/cm2 could enhance the inhibition of enamel demineralization, under a high cariogenic challenge. For this study, 80 specimens of sound primary enamel were selected after timely analysis by Energy Dispersive X-ray Fluorescence Spectroscopy (?-EDXRF) and randomly divided into 4 groups: control (C), 1 application of CO2 laser (L1), 2 applications of CO2 laser (L2) and 3 applications of CO2 laser (L3). The specimens were evaluated by ?-EDXRF before laser applications and after pH cycling. Right after the specimens was submitted to Cross-Sectional Enamel Micro-hardness (CSEM) and Scanning Electron Microscopy (SEM) analyses. The results were analyzed by ANOVA followed by t- test, Kruskal-Wallis test, a paired t test and simple logistic regression analysis (p<0.05). CSEM data showed a statistically significant difference between control and all irradiated groups (p<0.01), but no difference was found between the irradiated L1 and L2 groups (p>0.05). The lowest enamel mineral loss occurred in L3 group (p<0.01). The ?-EDXRF results showed a significant decrease of Ca only on the L1 group. The results of paired t test showed that calcium content was higher only in primary enamel submitted to two laser applications (p=0.046). SEM results showed that with repeated applications of the CO2 laser, a progressive melting and recrystallization of the enamel surface occurred. In conclusion, our results showed that three repeated irradiations of primary dental enamel with a CO2 laser significantly enhanced the inhibition of primary enamel demineralization
Mestrado
Odontopediatria
Mestra em Odontologia
44
Majeed, Abdul. "Efficacy and safety of various tooth-whitening products, with special reference to the three dimensional colour space (L*a*b*) measurements and the microhardness tests." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6162_1319790550.
Full textAbstract:
Tooth-whitening or tooth-bleaching has become an integral part of modern dental practice. Today, a large number of whitening products are available on the market which are commonly categorized into dentist-supervised home bleaching, in-office bleaching and over-the-counter bleaching products according to their mode of application. This thesis looks into safety and efficacy of various tooth-whitening products and methods.
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Velo, Marilia Mattar de Amoêdo Campos 1984. "Validation of a pH-cycling model to evaluate the effect of fluoridated toothpastes on enamel demineralization of human primary teeth = Validação de modelo de ciclagens de pH para avaliar o efeito de dentifrícios fluoretados na desmineralização do esmalte de dente decíduo humano." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290563.
Full textAbstract:
Orientador: Cínthia Pereira Machado TabchouryDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O efeito de dentifrícios fluoretados na prevenção da cárie dentária na dentição decídua é concentração-dependente. No entanto, não há um modelo de ciclagens de pH validado em termos de dose-resposta ao fluoreto (F) para esmalte de dente decíduo humano. Assim, esse estudo validou um modelo de ciclagens de pH em termos de dose-resposta ao F para avaliar a desmineralização do esmalte de dente decíduo, e posteriormente, o modelo foi testado com dentifrícios comerciais com diferentes concentrações de F. Dois estudos independentes foram realizados e blocos de esmalte de dente decíduo (3 X 3 X 2 mm), selecionados pela dureza de superfície, foram usados em ambos. Para validar o modelo, blocos dentais (n=12/grupo) foram submetidos ao modelo de ciclagens de pH e tratados duas vezes ao dia com: água purificada (controle negativo) e soluções contendo 62,5; 125, 250 e 375 ?g F/mL. Essas concentrações de F foram escolhidas para simular a diluição (1:3 g/g) que ocorre na cavidade oral quando dentifrícios contendo 250, 500, 1000 e 1500 ?g F/g, respectivamente, são usados. O modelo durou 10 dias e os blocos permaneceram diariamente por 6 h em solução desmineralizante e 18 h em solução remineralizante a 37°C. Após a validação, o modelo foi testado com dentifrícios comerciais e blocos de esmalte (n=15/grupo) foram tratados com: dentifrício não fluoretado, 500 ?g F/g, como dentifrício de baixa concentração de F, 1100 e 1450 ?g F/g, como dentifrícios convencionais. A porcentagem de perda de superfície (%PDS) e área da lesão de cárie (?S) foi determinada. O efeito dose-resposta ao F foi analisado por regressão quadrática e o efeito do teste com dentifrícios pelo teste de Tukey. O modelo mostrou relação dose-resposta entre concentração de F e %PDS (R²=0,7047; p<0,01) e ?S (R²=0,4465; p<0,01). Quando o modelo de ciclagens de pH foi usado para avaliar o potencial anticárie de dentifrícios fluoretados comerciais, a média (±DP) de %PDS e ?S para o grupo tratado com 500 ?g F/g foi 36,6±8,0 e 6298,5±1221,3, respectivamente, os quais foram significativamente maiores que os grupos tratados com dentifrícios de 1100 (25,2±8,7 e 4565,7±1122) e 1450 ?g F/g (24,2±5,2 e 2339,1±879,7), respectivamente. Em conclusão, o modelo proposto validado é capaz de diferenciar o potencial anticárie de dentifrícios de baixa concentração de F (500 ?g F/g) dos dentifrícios de concentração convencional (1000-1500 ?g F/g)
Abstract: The effect of fluoridated toothpaste on dental caries prevention in primary dentition is concentration-dependent. However, there is no pH-cycling model validated to assess the dose-response to fluoride (F) in human primary teeth enamel. Thus, this study validated a pH-cycling model in terms of dose-response to F to evaluate primary teeth enamel demineralization, and later, the model was tested with commercial toothpastes with different F concentrations. Two independent studies were conducted and primary teeth enamel slabs (3 X 3 X 2 mm), selected according to the surface hardness, were used in both. To validate the model, dental slabs (n=12/group) were submitted to the pH-cycling model and treated twice a day with: purified water (negative control) and solutions containing 62.5; 125; 250 and 375 ?g F/mL. These F concentrations were chosen to simulate the dilution (1:3 w/w) that occurs in the oral cavity when dentifrices containing 250, 500, 1000 and 1500 ?g F/g, respectively, are used. The model lasted 10 days and the slabs remained daily for 6 h in a demineralizing solution and 18 h in a remineralizing solution at 37°C. After validation, the model was tested with commercial toothpastes and enamel slabs (n=15/group) were treated with: no F toothpaste, 500 ?g F/g, as low F toothpaste, 1100 and 1450 ?g F/g, as standard toothpastes. The percentage of surface microhardness loss (%SMHL) and the carious lesion area (?S) were determined. The dose-response effect to F was analyzed by quadratic regression and the toothpaste effect by Tukey¿s test. The model showed dose-response relationship between F concentration and %SMHL (R²=0.7047; p<0.01) and ?S (R²=0.4465; p<0.01). When the pH-cycling model was used to evaluate the anticaries potential of commercial toothpastes, the mean (±SD) of %SMHL and ?S for the group treated with 500 ?g F/g was 36.6±8.0 and 6298.5±1221.3, respectively, which were significantly higher than those treated with 1100 (25.2±8.7 and 4565.7±1122) and 1450 ?g F/g toothpastes (24.2±5.2 and 2339.1±879.7), respectively. In conclusion, this validated model is able to differentiate the anticaries potential of toothpaste with low F concentration (500 ?g F/g) from those with standard concentrations (1000-1500 ?g F/g)
Mestrado
Cariologia
Mestra em Odontologia
46
Porto, Isabel Maria. "Mineralização do esmalte apos a remoção parcial dos ameloblastos pos-secretorios em incisivos inferiores de ratos." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288571.
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Orientador: Raquel Fernanda GerlachDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O órgão do esmalte de incisivos de ratos no estágio de maturação da amelogênese (região em que os prismas de esmalte são visíveis e o esmalte é completamente solúvel em ácido) foi removido, e os limites desta remoção (região cirúrgica) foram demarcados por marcas feitas na face labial do esmalte. O órgão do esmalte, da região acima da marca incisal até a crista alveolar, foi danificado utilizando-se uma lima endodôntica e foi feita a ressecção do órgão odontogênico na extremidade basal do incisivo. Os ratos foram divididos em dois grupos: I ¿ quando a marca incisal e II ¿ quando a marca basal apareceu na coroa clínica. Os incisivos experimentais erupcionaram em uma taxa variável e mais lenta que os dentes contralaterais controles. O aspecto histológico do esmalte na região cirúrgica dos ratos do grupo I variou de um esmalte completamente removido pelo descalcificador a resquícios de esmalte com prismas visíveis. Nessa mesma região no grupo II, todo o esmalte estava completamente solúvel em ácido. A microdureza do esmalte na região cirúrgica foi menor nos incisivos experimentais, enquanto o conteúdo mineral (Ca e P) não apresentou diferença em relação ao dente controle. A análise protéica do esmalte dos incisivos, uma semana após a cirurgia, revelou uma quantidade e um padrão de eletroforese similar entre os dentes controle e experimental na região cirúrgica. Na região pós-cirúrgica, o conteúdo protéico do esmalte do dente experimental foi muito menor e mostrou proteínas de baixo peso molecular em relação à região correspondente nos incisivos controles. Os resultados são consistentes com a hipótese de que o ameloblasto no estágio da maturação não interfere no influxo de minerais no esmalte
Abstract: The enamel organ of rat incisors at the maturation stage of amelogenesis (from the region were enamel rods are visible and the enamel is completely acid-soluble) was removed and the limits of the removal (surgical region) were marked by notches made at the labial face of the enamel. The enamel organ, from the incisal notch up to the alveolar crest, was damaged by an endodontic file and the odontogenic organ at the basal end of the incisor was resected. The rats were divided into two groups: I ¿ when the incisal mark and II when the basal mark appeared at the clinical crown. The experimental incisors erupted at a variable and slower rate than the contralateral controls. The histological aspect of the enamel at the surgical region of rats of group I varied from enamel completely removed by demineralization to remaining of enamel showing rods. In the same region of group II all enamel was completely acid-soluble. Microhardness of the enamel at the surgical region was lower in experimental incisors, while the mineral content (Ca and P) did not differ from the control teeth. Protein analysis of enamel from incisors, one week after surgery, showed an amount and an electrophoresis pattern similar in experimental and control teeth at the surgical region. In the post-surgical region, the protein content of enamel of experimental teeth was much lower and showed more proteins of lower molecular weight than the correspondent region of the control incisors. The results are consistent with the hypothesis that the ameloblast at the maturation stage do not interfere with the influx of minerals into the enamel
Mestrado
Histologia e Embriologia
Mestre em Biologia Buco-Dental
47
CARA, ANA C. B. de. "Avaliação do processo de desenvolvimento de desmineralização em esmalte dental humano utilizando a técnica de tomografia por coerencia óptica." reponame:Repositório Institucional do IPEN, 2012. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10112.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
FAPESP:10/03123-8
48
Soeiro, Caio Raphael Martins. "Resistencia a união e padrão de condicionamento em esmalte de sistemas adesivos autocondicionantes aplicados de forma passiva ou ativa." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289761.
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Orientadores: Luiz Andre Freire Pimenta, Roger William F. MoreiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Os obje1ivos deste estudo "ín vítro" foram avaliar a resistência de união ao esmalte e o padrão de condicionamento ob1ido por sistemas adesivos autocondicionantes quando aplicados de forma passiva e a1iva. Foram utilizados 100 dentes bovinos, em que o esmalte ves1ibular foi regularizado através de desgaste superficial. Os corpos-de-prova foram divididos aleatoriamente em 10 grupos (n= 10). Foram 1ilizados um adesivo convencional (Single Bond/3MESPE - SB) e 4 adesivos autocondicionantes (Tyrian SPE/BISCO - TY; Clearfil SE Bond/Kuraray - CL; One Up Bond F/Tokuyama - OU e Prompt-LPop/3MESPE - PL). Para cada sistema adesivo exis1iram dois grupos experimentais. Um no qual o adesivo foi aplicado de forma passiva (P) (Durante o tempo de espera prévio a polimerização, o adesivo foi man1ido em repouso). E outro em que o adesivo foi aplicado de forma a1iva (A) (Durante o tempo de espera, o adesivo esteve sendo re-aplicado até que o tempo de espera cessasse). Para o grupo controle, os dentes foram condicionados com ácido fosfórico 35%/3M/ESPE durante 30 segundos, lavados com spray de água por 15 segundos e secos com papel absorvente. O adesivo Single Bond foi aplicado segundo as recomendações do fabricante para o grupo experimental 1 (Controle passivo). O mesmo procedimento foi realizado para o grupo 2 (Controle a1ivo), exceto a forma de aplicação. Para os demais grupos, os dentes receberam a aplicação de cada adesivo nas recomendações de cada fabricante, de maneira passiva e ativa, Os corpos-de-prova foram restaurados com resina Filtek Z-250/3MESPE, através da confecção de um "bloco" de resina. Através de cortes em máquina de cortes seriados, foram ob1idos espécimes em forma de "palito" com uma área de secção transversal de aproximadamente 1,Omm2 que foram individualmente fixados ao disposi1ivo para ensaio de microtração (MT -JIG) de modo a posicionar a área de união perpendicularmente ao longo eixo da força de tração, feita em máquina de ensaio universal/EMIC DL500. Os valores de resistência à união foram subme1idos à análise de variância (fatorial) e Teste de Tukey. Os resultados, em MPa/desvio padrão para cada grupo foram: SB/P - 10,86 (3,50)Ba; SB/A 13,39 (1 ,24)Aa; TY/P - 9,17 (3, 19)Aab; TY/A - 8,21 (3,88jAbc; CL/P - 8,58 (2,46jAab; CL/A - 10,23 (3,58jAabc; OU/P - 6,24 (1,61)Bb; OU/A - 11,90 (2,12jAab; PL/P - 7,97 (0,91jAab; PL/A - 7,22 (2,05jAc. Para análise do padrão de condicionamento, foram u1ilizados 45 dentes bovinos (n=5). Para os grupos 1 e 2 (Controles), 5 dentes foram condicionados com ácido fosfórico 35% por 30 segundos, lavado com spray de água por 15 segundos e secos com jatos de ar. Os sistemas adesivos autocondicionantes foram aplicados de forma passiva e a1iva. Cada espécime foi lavado com água por 15 segundos, com acetona por 10 segundos e seco com jatos de ar, sendo então levadas ao microscópio eletrônico de varredura JEOL 5600 LV. As imagens sugeriram relação entre o padrão de condicionamento e os valores de resistência à união ob1idos, os quais mostraram diferenças estaiís1icas para alguns dos adesivos avaliados
Abstract: The aim of this study were evaluate the bond strength and conditioning pattern obtained from different self-etching adhesive systems applied on enamel by active and passive forms. 100 bovine incisors were sectioned in 6x6mm fragments from the buccal enamel surface. The specimens were divided into 10 groups (n= 1 O). It was used one single bottle adhesive system (Single Bond/3MESPE - SB) as Control and four self-etching adhesive systems (Tyrian SPE/BISCO - TV; Clearfil SE Bond/Kuraray - CL; One Up Bond F/Tokuyama OU and Prompt-LPop/3MESPE - PL). For each adhesive system, there were two experimental groups, The adhesive was applied by passive form (P) (during the waiting time previous the polymerization, the adhesive was left intact over the enamel surface) or the adhesive was applied by active form (A) (the adhesive was reapplied during the waiting time previous the polymerization). For the Con1rol group, the tooth were conditioned with 35% phosphoric acid/3MESPE for 30 seconds, washed with water spray for 15 seconds and lot dried with absorbent paper. Single Bond was applied following the manufacture's ins1ructions (passive con1ro! group)(Group 1). The same procedure was made for active con1rol group (Group 2), except during the waiting time previous the polymerization, the adhesive was continuously reapplied on the enamel surface, The self-etching adhesives were applied following the manufacturer's instructions, receiving both applications forms (passive and active). The specimens were restored with Filtek Z-250/3MESPE, Using a saw machine, were obtained specimens in a stick (beam) shape with 1,Omm2 1ransversal sectional area, Those sticks were individually fixed in a microtensile jig, attached in an universal testing machine. The bond strength values were analyzed by Two-way ANOVA and Tukey's test. The means, and standard deviations, expressed in MPa, were: SB/P - 10,86 (3,50)Ba; SB/A - 13,39 (1 ,24)Aa; TV/P - 9,17 (3, 19)Aab; TV/A - 8,21 (3,88)Abc; CljP 8,58 (2,46)Aab; CljA - 10,23 (3,58)Aabc; OU/P - 6,24 (1,61 )Bb; OU/A - 11,90 (2,12)Aab; PljP - 7,97 (0,91 )Aab; PL/A - 7,22 (2,05)Ac, For conditioning pattern analysis, 45 bovine incisors (n=5) were used. For groups 1 and 2, the teeth were conditioned with 35% phosphoric acid for 30 seconds, washed with water spray for 15 seconds and air dried, The self-etching adhesives were applied by passive and active forms. After that, those specimens were washed with water spray for 15 seconds, washed with acetone for 10 seconds and air dried. The specimens were prepared for SEM and observed in a JEOL 5600 LV. The images suggested that the conditioning pattern is related to bond s1rength values, that presented statistical differences for some adhesives studied.
Mestrado
Dentística
Mestre em Clínica Odontológica
49
Franco, Laura Molinar [UNESP]. "Remoção de irregularidades superficiais do esmalte dental após a remoção de braquetes ortodônticos: efeito de polimentos superficiais e tempos de análise." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/151818.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo deste ensaio clínico foi avaliar o comportamento de dois sistemas de polimento na regularização da superfície do esmalte dental, que apresentava-se rugosa e irregular após a remoção de braquetes ortodônticos. As variáveis de resposta foram: rugosidade superficial, luminosidade, morfologia, textura e sensibilidade. Fizeram parte dessa pesquisa clínica 30 voluntários. Os fatores em estudo foram: as técnicas de poli- mento superficial em dois níveis: Técnica 1 (discos de óxido de alumínio) e Técnica 2 (produto ácido-abrasivo), e o tempo de análise em 5 níveis: T0 (baseline), T1 (imedia- tamente após os polimentos superficiais), T2 (após polimento final), T3 (7 dias após os procedimentos) e T4 (6 meses após os procedimentos). Os dados representados por escores foram analisados considerando distribuição multinomial; os dados numéricos foram analisados como medidas repetidas no tempo, a um nível de significância de 5%. Nas análises de rugosidade superficial e luminosidade, não houve diferença estatística entre as técnicas em todos os tempos analisados. Nas análises por score, dentro de cada tempo, verificou-se igualdade significativa apenas no baseline; nos demais tempos foram observadas irregularidades superficiais estatisticamente superiores para a Técnica 1. Nenhum paciente apresentou sensibilidade dental. Ambas as técnicas foram eficientes; porém a maior lisura foi adquirida quando a Técnica 2 foi utilizada.
This clinical study evaluated the behavior of two surface polishing systems in the regularization of the enamel surface, which was rough and irregular after orthodontic brackets debonding. The response variables were: surface roughness, lightness, morphology, texture and sensitivity. Thirty volunteers were part of this clinical research. The factors under study were: Surface polishing at two levels: Technique 1 (aluminum oxide disks) and Technique 2 (enamel microabrasive product); and the Time of analysis at 5 levels: T0 (after surface polishing), T1 (immediately after surface polishing), T2 (after final polishing), T3 (7 days after surface polishing) and T4 (6 months after surface polishing). The data represented by scores were analyzed considering multinomial distribution; the numerical ones were analyzed as measures repeated in time, at a significance level of 5%. In the analysis of surface roughness and lightness, there was no statistical difference between the polishing techniques at all times analyzed. In the other analyzes, within each time, significant equality was observed only in the baseline, while in the other times superficial irregularities were statistically superior for Technique 1. No patient presented dental sensitivity. Both techniques were efficient; however, the higher surface smoothness was observed on the dental enamel surface polished with the Technique 2.
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Viana, Patricia Gabriela Sabino [UNESP]. "Influência de diferentes métodos de esterilização de esmalte dental sobre a sua morfologia, composição química, estrutura e formação de biofilmes in vitro." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/127543.
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000839097.pdf: 4137488 bytes, checksum: e361e28e2b4d90c452faabd674b87f64 (MD5)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O processo de esterilização deve preservar as propriedades do esmalte utilizado nas pesquisas in vitro e in situ. O objetivo deste estudo foi avaliar a influência dos métodos de esterilização Irradiação por micro-ondas - IM, Irradiação gamma - IG, Óxido de etileno - OE e Autoclave - AU sobre as propriedades do esmalte. O estudo foi realizado em duas fases. Na fase 1, 50 espécimes de esmalte bovino foram divididos em cinco grupos (n=10): IM, IG, OE, AU e controle (não esterilizado). Foram realizadas avaliações quanto à morfologia (Microscopia Eletrônica de Varredura - MEV superficial e em secção transversal), composição química (Energia Dispersiva de raios-X - EDS e Espectroscopia Fotoeletrônica por raios-X - XPS) e estrutura (Raman e Ressonância Magnética Nuclear - RMN). Na fase 2, 360 espécimes de esmalte bovino foram divididos em quatro grupos (n=90): IM, IG, OE e AU. Biofilmes monoespécie (Actinomyces naeslundii e Streptococcus sanguis) e biofilmes mistos foram formados e avaliados, para cada grupo experimental, quanto ao número de unidades formadoras de colônias por mililitro (UFC/mL; n=10), atividade metabólica (redução do 2 metoxi 4 nitro 5 sulfofenil 5 fenilalanina carbonil 2H tetrazolium hidróxido - XTT; n=10) e biomassa total (cristal violeta; n=10). A análise estatística dos dados foi realizada para as avaliações Raman, XPS, UFC/mL, XTT e cristal violeta com ɑ=0,05. Os resultados indicaram que o método IG não promoveu alterações sobre a morfologia, composição química e estrutura do esmalte. Os grupos IM e EO promoveram pequenas alterações na morfologia superficial, composição química e estrutura. O grupo AU resultou em severas alterações na morfologia superficial e em secção transversal, com pequena 9 influência sobre a composição química e estrutura do esmalte. Os biofilmes de S. sanguis não apresentaram diferenças...(Resumo completo, clicar acesso eletrônico abaixo)
The sterilization process should preserve the enamel properties of specimens used for in vitro and in situ studies. The aim of this study was to evaluate the influence of sterilization methods Microwaving - MI, Gamma irradiation - GI, Ethylene oxide - EO and Steam autoclave SA on the enamel properties. This study was conducted into 2 phases. For phase 1, 50 specimens of bovine enamel were assigned into 5 groups (n=10): MI, GI, EO, SA and control (no sterilization), evaluated regarding morphology (Scanning Electron Microscopy - SEM superficial and cross-section), chemical composition (X-ray energy dispersive spectroscopy - EDS and X-ray photoelectron spectroscopy - XPS) and structure (Raman and Nuclear Magnetic Resonance - RMN). For phase 2, 360 bovine enamel specimens were assigned into 4 groups (n=90): MI, GI, EO and SA. For each group, biofilms were grown as monospécies (Actinomyces naeslundii and Streptococcus sanguis) and multispecies, evaluated regarding counting forming units (CFU/mL), metabolic activity (reduction of 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide - XTT) and biomass (violet crystal assay). Statistical evaluation was performed for data from XPS, Raman, CFU/mL, XTT assay and violet crystal assay. The results indicated that GI group produced no alterations on the morphology, chemical composition and structure of the enamel. MI and EO groups promoted slightly alterations on morphology, chemical composition and structure. The SA group caused severe morphological changes on surface and in depth and small alterations on chemical composition and structure. There were no differences among groups for S. sanguis biofilms. A. naeslundii biofilms showed higher values of CFU/mL and biomass for SA group and higher metabolic activity in GI group. It can be concluded that enamel properties could be influenced ...(Complete abstract electronic access below)
FAPESP: 2011/09416-0