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Structural and Chemical Aspects of Calcium Phosphate Formation in Tooth Enamel
Kallistová, Anna ; Skála, Roman (advisor) ; Frýda, Jiří (referee) ; Oldak, Janet (referee)
Tooth enamel is the hardest and most resistant highly mineralized inorganic component in mammalian bodies that significantly affects both the life quality and expectancy of an indi- vidual. Its specific qualitative properties are given by the biomineralization process responsible for its formation. In this process the mineralization of hydroxyapatite (HAp), the only inor- ganic phase composing the mammalian hard tissues, is controlled by activity of enamel-forming cells ameloblasts and their products. Over the past years, the studies of enamel matrix pro- teins, their structure, composition and function has become the prevalent field of experimental investigation. However, unique enamel qualities, which enable the teeth to withstand high pressure and stress demands, cannot be accurately assessed without the thorough systematical study of its mineral compound. In this thesis, I focus on the crystallographic and compositional characteristics of enamel hydroxyapatite and their influence on the mechanical properties of teeth. Obtained results are discussed in context of developmental and adaptation dynamics of mammalian species. The main aspect of the work is to extend our knowledge about the protein-mediated mineraliza- tion process from the perspective of inorganic compound and its contribution to the...
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Long-term durability of composite restoration margins in environments with increased corrosion risk
Roubíčková, Adéla ; Bradna, Pavel (advisor) ; Veverka, Jan (referee) ; Halačková, Zdena (referee)
Introduction: An adhesive bond between hard dental tissues and composite reconstructions is exposed to mechanical load, water, bacteria, enzymes and different chemical compounds. These factors could impair durability and resistance of composite reconstructions. In contrast with extensive research of negative influence of water on degradation of adhesive bonds, the influence of chemical substances on adhesive bond has not been investigated to a greater extent. Aim: The aim of the experimental part of the thesis was to evaluate the influence of hydrogen peroxide containing tooth-whitening products and mouth rinses containing chlorhexidine and fluoride on a long-term stability of class V composite restorations created using four contemporary adhesive systems by a microleakage method. Materials and methods: The following adhesive systems were investigated: total-etch Gluma Comfort Bond (GLU), and self-etch adhesives Clearfil SE Bond (CLF), Adper Prompt (ADP) and iBond (IBO). Standardized class V cavities were prepared in 192 extracted human teeth (one cervical margin in the cementum and one in the enamel). Subsequently, the cavities were restored using microhybride composite Charisma. The specimens were then exposed to the tooth whitening system Opalescence PF 20, mouth rinse Corsodyl containing...
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Proteomic study of human tooth dentin
Zettlová, Ludmila ; Jágr, Michal (advisor) ; Vrbacký, Marek (referee)
Proteome analysis of dentin in human teeth adult subjects was conducted to optimize the two dimensional gel electrophoresis (2-DE) analysis of proteins from the dental tissue. The third molar teeth were cleaned, crushed and extracted in guanidine and EDTA buffer. Extracted proteins were separated by 2-DE, digested with trypsin to peptides and subsequently analyzed using nLC MS/MS. Totally, 7 unique proteins were identified in the samples. The use of IPG strips with different range of the pH gradient and the subsequent comparison of 2 DE gels unfortunately did not bring important new information, because common keratin, collagen and serum albumin proteins were identified.
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Effect of corrosion environment on the long-term stability of composite material to enamel and dentin bonds
Dudek, Michal ; Bradna, Pavel (advisor) ; Veverka, Jan (referee) ; Halačková, Zdena (referee)
Introduction: Adhesive technology represents a significant advancement among different treatment options of dental caries. Its advantages involve not only highly aesthetic reconstructions, but also ability to preserve hard dental tissues compared to more traditional filling materials such as amalgam, where the material retention was achieved through undercuts. A potential of adhesive technology to arrest progression of an incipient caries has triggered its wider use in dental caries management, potentiated by an ongoing development of new adhesive systems and composite materials that assure an acceptable long-term stability of adhesive reconstructions. Adhesive bonds of dental reconstructions are in the oral cavity constantly challenged by various mechanical, chemical and biological factors. One of the chemical agents with detrimental potential is peroxide bleaching gel used for teeth brightening. Currently bleaching belongs to the most frequent cosmetic dental procedures. The active ingredient of bleaching gels is hydrogen peroxide or its precursors. It is assumed that free oxygen radicals released from peroxides attack double bonds of chromophore molecules captured within the tooth tissues. Because of the high reactivity and nonspecific nature of these oxygen radicals, they may affect also dental...
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Pozorování zubní skloviny a dentinu v SEM
Wandrol, Petr ; Roubalíková, L. ; Autrata, Rudolf
The purpose of this study was to investigate whether the acidic monomer based on the phosphoric acid ether acrylate can create the same retentive pattern in enamel and dentin as the conventional treatment with the 37% phosphoric acid. The surface of enamel in the AdHeSe group was slightly undulated, the retentive pattern was regular and moderate. In the TotalEtch group more irregularities and a clearer retentive pattern were observed. The dentin surface was similar in both groups- it was clean without the smear layer, the dentin tubuli were open, the collagen network was seen on the dentin surface as well as in the dentin tubuli.
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