Electron microscopic and X-ray diffraction investigations of nanostructured thin films of ZnO
ZnO films prepared by sol-gel technique using zinc nitrate and zinc acetate as precursor material have been studied using transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. The results show the formation of zinc oxide phase. The nanostructure of the films was studied by transmission electron microscopy. Nano-structured fine grains of size ranging from 20-60 nm were observed with zinc nitrate precursor film. Individual grains show a sharp contrast with different facets and boundaries. Films prepared by zinc acetate precursor show ultra-fine nano-grains in the shape of dendrites as seen by the TEM. XRD shows a larger size of crystallites with the zinc acetate precursor. Crystal planes and lattice parameters calculated by both electron diffraction and X-ray diffraction are quite close and in agreement with the reported values in literature.
Characterization of thin films of ZnO prepared by sol-gel processes
Thin films of ZnO have been grown using sol-gel technique. The precursor materials for sol preparation include zinc acetate or zinc nitrate. Characterization was done using optical absorption, ellipsometry, X-ray diffraction, photoluminescence and scanning electron microscopy.
Endodontic regeneration: hard shell, soft core
A loss of organs or the destruction of tissue leaves wounds to which organisms and living things react differently. Their response depends on the extent of damage, the functional impairment and the biological potential of the organism. Some can completely regenerate lost body parts or tissues, whereas others react by forming scars in the sense of a tissue repair. Overall, the regenerative capacities of the human body are limited and only a few tissues are fully restored when injured. Dental tissues may suffer severe damage due to various influences such as caries or trauma; however, dental care aims at preserving unharmed structures and, thus, the functionality of the teeth. The dentin–pulp complex, a vital compound tissue that is enclosed by enamel, holds many important functions and is particularly worth protecting. It reacts physiologically to deleterious impacts with an interplay of regenerative and reparative processes to ensure its functionality and facilitate healing. While there were initially no biological treatment options available for the irreversible destruction of dentin or pulp, many promising approaches for endodontic regeneration based on the principles of tissue engineering have been developed in recent years. This review describes the regenerative and reparative processes of the dentin–pulp complex as well as the morphological criteria of possible healing results. Furthermore, it summarizes the current knowledge on tissue engineering of dentin and pulp, and potential future developments in this thriving field.