Search

Light-curing composite restorative materials are widely used by dentists of various specialties in the esthetic restoration because of their optimal mechanical properties and predictable desired aesthetics. However, their use requires special attention to the safety of the components used. In recent decades, polymer composites have been developed with the objective of reducing cytotoxicity and shrinkage during polymerization and improving aesthetics. The biocompatibility of all polymeric materials is an issue that requires special focus on the chemical composition of biopolymers, which consist of an organic resin matrix and ceramic reinforcing filler particles bonded with a silane. The special priority in biocompatibility studies has focused mainly on the organic resin polymer matrix. And among the components of composite resins, the polymer matrix is the only unstable one, mainly because of the unbound monomers that can be released and remain as free monomers during the polymerization step. The aim of this study was to evaluate the effectiveness of preheating composite restorative materials on composite conversion and their cytotoxic properties. The use of composite restorative materials preheating in dental practice allows dentists to reduce the cytotoxicity of composite materials and improve their degree of conversion, since there is a direct relationship between increasing the conversion of the material and reducing its cytotoxicity. Preheating has a positive effect on composite, resulting in reducing their cytotoxic properties and optimizing the biocompatibility of the polymer matrix with hard tissues. The conversion of the material is improved, since there is a direct correlation between the increase in the conversion of the material and the reduction of its cytotoxicity. [ABSTRACT FROM AUTHOR]

Tooth restoration involves the use of various types of materials. In modern reality, light-curing composite materials are used for this purpose. Also, polymer cements of various types of polymerization are used to fix indirect structures in highly aesthetic areas. All dental composites are polymerized according to the free radical type. The formation of free radicals and curing occur as a result of a thermal, chemical, or photochemical reaction. Polymerization of composites never occurs at 100%; upon contact with air, the surface of the material interacts with oxygen, which leads to the termination (inhibition) of the polymerization reaction. To prevent the formation of an oxy-geninhibited layer (OIL) on the surface of the composite, chemically inert, oxygen-impermeable protective glycerol gels are used. To evaluate the feasibility and effectiveness of glycerol in preventing the oxygen-inhibited layer formation and to determine the relationship between the group of the composite and its qualitative composition during the formation of an oxygen-inhibited layer during polymerization. This study was carried out using an Infralum FT-801 IR Fourier spectrometer in KBr tablets. 135 samples of 12 various composite materials were studied; each was subjected to IR spectrometry, cured in glycerol or without glycerol. 15 specimens of Enamel plus UE composite material underwent pre-polymerization heat in a special oven (Micerium; Avegno, Italy) to 55°C before one heating cycle. The obtained results allowed us to conclude that the type of composite material does not significantly affect the process of oxygen inhibited layer formation. Regardless of the composite material group, under aerobic conditions, an incomplete conversion occurs, and an oxygen inhibited layer is formed. Anaerobic conditions do the conversion completely, which leads to the absence of oil, which was confirmed by infrared spectroscopy data. [ABSTRACT FROM AUTHOR]

Prosthodontic restorations made of zirconium dioxide are popular. An important step in prosthetics is the cementing of a zirconium dioxide crown on the tooth. For high-quality adhesion, the inner surface must be cleaned of saliva and blood contamination. The aim of the study is systematic review on the impact of the method on the quality of cleaning of zirconium dioxide restorations after contamination with saliva. Electronic search of articles was carried out using search engines and databases Google Scholar, Pub Med. Articles are included, the content of which relates to the topic of methods of purification of zirconium dioxide after contamination with saliva. The publication date criterion has been selected since 2013. 69 articles were reviewed during the review process. After analyzing the literature according to the inclusion criteria, the total number was 50 publications. There are many methods of cleaning zirconium dioxide from saliva contamination. There are commercial products on the dental market that show good results. Additional research methods are needed to determine the most effective method of contamination from saliva contamination. [ABSTRACT FROM AUTHOR]