Examination of Native and Carbamide Peroxide-bleached Human Tooth Enamel by Atomic Force Microscopy

2009 ◽  
Vol 33 (5) ◽  
pp. 189-196 ◽  
Author(s):  
Christoph Mahringer ◽  
Monika Fureder ◽  
Markus Kastner ◽  
Andreas Ebner ◽  
Peter Hinterdorfer ◽  
...  
2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Vladan Mirjanić ◽  
Đorđe Mirjanić

Bearing in mind that in the field of jaw orthopedics and related scientific fields, there are no scientific studies that use the most modern technology based on the Atomic Force Microscopy (AFM) to investigate the nanostructure of tooth enamel after etching with 37% orthophosphoric acid, in this paper we will use this method, which is currently the most reliable, to determine the degree of tooth damage after its etching in the process of fixing orthodontic brackets. Considering the fact that the degree of enamel damage after etching cannot be realistically comprehended by the method called ’network’, because in this way the damage cannot be seen three dimensionally (the depth of the damage), but only the damage in a single plane, a more precise analysis can be obtained with the application of the most contemporary method that we can apply in this case, and that is the application of AFM technology.


2016 ◽  
Vol 10 (01) ◽  
pp. 082-091 ◽  
Author(s):  
Thayla Hellen Nunes Gouveia ◽  
Juliana do Carmo Públio ◽  
Glaucia Maria Bovi Ambrosano ◽  
Luís Alexandre Maffei Sartini Paulillo ◽  
Flávio Henrique Baggio Aguiar ◽  
...  

ABSTRACT Objective: To evaluate the influence of 16% carbamide peroxide (CP) containing different thickeners on the physical characteristics of a nanocomposite resin submitted or not to accelerated artificial aging (AAA). Materials and Methods: One hundred samples were randomly distributed into two groups (n = 50) according to AAA. Each group was divided into 5 subgroups (n = 10) depending on the bleaching/thickener treatment: CP + carbopol, CP + natrosol, carbopol, natrosol, and no treatment (control). The physical properties tested were color (ΔE), gloss (GU), mean roughness (Ra), and Knoop microhardness (KHN). The resin surface was performed with atomic force microscopy (AFM). Statistical Analysis: The color (variable Δ E) was assessed with two-way analysis of variance (ANOVA) and additionally with Tukey's and Dunnett's tests, the roughness values were submitted to Kruskal–Wallis, Dunn's, and Mann–Whitney's tests. Data on gloss and KHN were submitted to two-way ANOVA and Tukey's test (α = 0.05). Results: Among the physical properties evaluated, CP + carbopol promoted a reduction in composite microhardness only, thus differing statistically from the controls. As for CP + natrosol, such a change was not observed. The aging process reduced all the physical properties, thus differing statistically from the nonaging group. CP + carbopol increased the roughness and decreased the gloss of aged resins, whereas natrosol reduced gloss only, which differed statistically from the controls. Conclusions: AFM showed evidence of the loss of organic matrix and exposure to load particles in the aged samples. Therefore, the replacement of carbopol with natrosol provided maintenance of the composite microhardness following bleaching. The aging process reduced the physical properties evaluated, and some changes were enhanced by the application of bleaching.


2014 ◽  
Vol 5 ◽  
pp. 36-43 ◽  
Author(s):  
Matthias Wasem ◽  
Joachim Köser ◽  
Sylvia Hess ◽  
Enrico Gnecco ◽  
Ernst Meyer

Amplitude-modulation atomic force microscopy (AM-AFM) is used to determine the retention properties of CaF2 nanoparticles adsorbed on mica and on tooth enamel in liquid. From the phase-lag of the forced cantilever oscillation the local energy dissipation at the detachment point of the nanoparticle was determined. This enabled us to compare different as-synthesized CaF2 nanoparticles that vary in shape, size and surface structure. CaF2 nanoparticles are candidates for additives in dental care products as they could serve as fluorine-releasing containers preventing caries during a cariogenic acid attack on the teeth. We show that the adherence of the nanoparticles is increased on the enamel substrate compared to mica, independently of the substrate roughness, morphology and size of the particles.


Author(s):  
И.Л. Шестель ◽  
В.В. Педдер ◽  
В.К. Леонтьев ◽  
Р.Н. Голых ◽  
Г.Г. Иванова ◽  
...  

В нарушении нормального течения обменных процессов, протекающих с участием эмали существенную роль, играют особенности ее структурной неоднородности. Подробная морфологическая микроскопическая характеристика этих структур в литературе отсутствует, что привело к необходимости установления наличия полостей и микрокапиллярной компоненты в системе структурной неоднородности интактной зубной эмали между ее поверхностью и дентином путём применения оптической инвертированной и атомно-силовой микроскопии. Проведено исследование 180 препаратов зубов. Для изучения микро- и ультраструктурного строения эмали предложена методика приготовления препаратов продольного шлифа интактной эмали зуба, включающая финишную ультразвуковую очистку образца. Дана морфологическая оценка структурной неоднородности интактной зубной эмали, обнаруженной при ее оптической инвертированной и атомно-сило-вой микроскопии, которая может быть применена в стоматологии для разработки инновационных методов диагностики, лечения и профилактики заболеваний зубов. Выявленные неоднородности в структуре ткани интактной эмали зуба представлены пустотами (полостями) в твердой фазе вещества эмали, позволяющими характеризовать эмаль как микрокапиллярно-пористую систему. Визуализировалась твердая фаза эмали и система иерархически организованных полостей, протяженных и взаимосвязанных между собой, упорядоченно и равномерно распределённых по всему объёму эмали зуба от ее поверхности до эмалево-дентинного соединения. Наличие таких сообщений указывает на возможность прямого обмена вещества в ткани эмали зуба как с поверхности, так и из корневого канала. Полученные при оптическом инвертированном и атомно-силовом микроскопировании данные создают представление о наличии между поверхностью эмали зуба и границей эмалево-дентинного соединения в эмали полых пространств – пор, сопряжённых с микрокапиллярами, значительно преобладающих над твердой фазой объема эмали. Система полостей в эмали зуба может быть выявлена при рутинном исследовании с использованием оптического инвертированного и атомно-силового микроскопов, что делает доступным изучение объектов, не требующего значительных временных и финансовых затрат. In violation of the normal course of metabolic processes occurring with the participation of enamel, the features of its structural heterogeneity play an essential role. Detailed morphological microscopic characteristics of these structures are not available in the literature, which led to the need to establish the presence of cavities and microcapillary components in the system of structural heterogeneity of intact tooth enamel between its surface and dentin by using optical inverted and atomic force microscopy. A study of 180 dental preparations was conducted. To study the micro- and ultrastructural structure of enamel, a method for preparing preparations of the longitudinal section of intact tooth enamel, including the final ultrasonic cleaning of the sample, is proposed. A morphological assessment of the structural heterogeneity of intact tooth enamel detected by its optical inverted and atomic force microscopy is given, which can be used in dentistry to develop innovative methods for the diagnosis, treatment and prevention of dental diseases. The revealed inhomogeneities in the structure of the intact tooth enamel tissue are represented by voids (cavities) in the solid phase of the enamel substance, which make it possible to characterize the enamel as a microcapillary-porous system. The solid phase of the enamel and a system of hierarchically organized cavities, extended and interconnected, orderly and evenly distributed over the entire volume of tooth enamel from its surface to the enamel-dentine junction were visualized. The presence of such messages indicates the possibility of direct exchange of substances in the tooth enamel tissue both from the surface and from the root canal. The data obtained by optical inverted and atomic force microscopy give an idea of the presence of hollow spaces - pores conjugated with microcapillaries in the enamel between the surface of the tooth enamel and the border of the enamel–dentine junction, significantly prevailing over the solid phase of the enamel volume. The system of cavities in the tooth enamel can be detected during routine examination using optical inverted and atomic force microscopes, which makes it possible to study objects that do not require significant time and financial costs.


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