Hydrothermal synthesis of hydroxyapatite (HA) is a method which is relatively easy to apply and enables HA precipitation on substrates of various shapes, which is vital to endoprostheses fabrication. Anodic oxidation facilitates HA precipitation, making the coating thicker and more uniform. In this paper the influence of anodic oxidation of titanium substrates on HA precipitation in hydrothermal synthesis is discussed. To determine chemical composition and coating uniformity of anodised and polished Ti substrates the Raman microspectroscopy was employed. The composition was also confirmed using X-ray diffraction method. HA coatings on Ti after anodic oxidation exhibit higher uniformity in comparison to untreated Ti. The X-ray diffraction patterns showed that the HA coating was partly amorphous. Also influence of additional treatment (soaking in NaOH and/or HBSS) after anodic oxidation is discussed in the present paper. It seems that pretreatment may be favourable in some cases, but if the anodic oxidation was conducted in the presence of calcium phosphates the pretreatment seems to prevent the HA precipitation.

The results provide a warning that clinical indications for in-stent radiation therapy must always be confronted with another aspect of the patient's history: the kind of implanted stent. Intravascular brachytherapy using pure beta sources may be recommended only for patients "wearing" light, thin-strut stents. The presence of thick-strut stents is a contraindication for this modality, due to excessive dose perturbation.

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In this work, the mechanical state of the material is considered in the form of the oscillation of the molecule. The analysis is carried out for material without an external load and for material under the action of the mechanical load. These two states are tested in a Raman spectroscope where oscillations of molecule with modulations are induced by laser light. One should expect that the results of these investigations will confirm the capability of Raman spectroscopy in analysis of molecular mechanical state of material.This research is carried out using photoelastic material, and an analogy to state of stress on the continuum level is presented by photoelastisity.