Eruption Pattern of Permanent Canines and Premolars in Polish Children.

Eruption is a complex and dynamic process determined by both genetic and epigenetic factors. This process involves a number of changes in the tissues surrounding the tooth and in tooth morphology. The aim of this study was to analyze the eruption sequence of permanent canines and premolars on the basis of pantomographic images. The study material consisted of 300 digital pantomographic images of children in the developmental period. The study group consisted of 165 boys and 135 girls. Images of patients of Polish nationality, aged 6-10 years, without diagnosed systemic diseases and local disorders were used in the study. Results: The study has shown that the most common pattern of tooth eruption in the lateral zones is type A positioning of the lateral teeth, which is 4-5-3. This pattern is characteristic of both girls and boys. This pattern also occurs most frequently in the maxilla in both boys and girls. In the mandible, on the contrary, two patterns of lateral tooth eruption were predominant. In girls, types A and E/4-5-3 and 3-4-5/occurred in the mandible, while in boys, types A and C/4-5-3 and 5-4-3/were observed in the mandible. The process of tooth eruption is a recognized measure of a child's physical development, and pantomographic images are an effective and common diagnostic tool.

Silica-filled methacrylic composites with extremely high compressive strength.

SYLOID® 244 has never been applied as a filler in composites with potential dental application. Therefore, the aim of research was to apply this silica in its unmodified and diazonium salt-modified forms in different mass ratios as fillers in light-cured methacrylic composites. The effectiveness of modification process was confirmed with the use of Raman spectroscopy. Methacrylic composites with the modified and unmodified SYLOID® 244, as well as unfilled resin as a control group were prepared. Their basic physicochemical properties, such as depth of cure, mass stability during incubation in saline, flexural and compressive strengths were examined. A positive effect of SYLOID® 244 modification on the properties of the examined composites was also demonstrated. The obtained results proved the high applicability of SYLOID® 244 as a filler in composites with potential dental applications.

Inverse gas chromatography in the examination of adhesion between tooth hard tissues and restorative dental materials.

The adhesion is a crucial issue in the bonding of dental restorative materials to tooth hard tissues. A strong and durable bond between artificial and natural materials is responsible for the success of the restoration in the oral cavity; therefore it has to be thoroughly examined before new restorative material is introduced to the market and used clinically. Among all methods used to examine bonding strength, most of them require a large number of healthy teeth to be conducted. In this paper, the bond strength between tooth hard tissues (dentin and enamel) and an exemplary restorative composite was examined with the non-conventional method, i.e. inverse gas chromatography. Dentin and enamel from bovine teeth were separated and subjected to the standard preparation procedure using the 3-component etch-and-rinse commercial bonding system. Tissues, as well as commercial restorative composite, were examined using inverse gas chromatography. The work of adhesion between dentin/enamel and composite was calculated. Obtained results were compared with the values of shear bond strength of six configurations, i.e. etched dentin/enamel-composite, primed dentin/enamel-composite, and bonded dentin/enamel-composite. All obtained results proved that there is a correlation between the values describing bond strength obtained from inverse gas chromatography and direct mechanical tests (shear bond strength tests). It proves that inverse gas chromatography is a powerful perspective tool for the examination of bond strength between tooth hard tissues and potential dental materials without using a large number of health tooth tissues.

Calcium-Rich 13X Zeolite as a Filler with Remineralizing Potential for Dental Composites.

A zeolite with high ion-exchange potential was used as an active filler with remineralizing potential in composites that can be applied in restorative dentistry. Two calcium-rich forms of the 13X zeolite were obtained by sodium to calcium ion exchange and mineralization of a hydroxyapatite layer. These fillers were also silanized and mixed with methacrylic resins and photoinitiators to obtain composite materials. First, the effectiveness of the filler preparation and silanization was confirmed by X-ray diffractometry, scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, nitrogen adsorption/desorption measurements, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The physicochemical characteristics of composites with silanized and nonsilanized forms of sodium- and calcium-rich 13X zeolite fillers were examined. The degree of conversion, depth of cure, flexural and compressive strength, mass stability, and remineralizing potential, understood as the ability to release calcium ions in the conditions simulating a natural oral environment, were determined. The effect of ion exchange, hydroxyapatite mineralization, and silanization of fillers on the final composites' properties was examined. Composites with calcium-rich fillers proved to show the ability to release Ca2+ during incubation in saline for 14 days at 36.6 °C showing therefore remineralizing potential with good values of other parameters.

Assessment of the Raman spectroscopy effectiveness in determining the early changes in human enamel caused by artificial caries.

Current diagnostic methods for enamel caries detection are unable to detect caries lesions at a very early stage. Previous studies indicated that Raman spectroscopy is a promising and effective tool for the detection of early caries. In our previous work, we showed that several independent parameters obtained during the analysis of the Raman spectra of enamel allow for the identification of carious lesions formed in the oral cavity (natural caries). The aim of this research was to estimate the effectiveness of Raman spectroscopy in the determination of specific changes in human enamel affected by artificial caries. The values of parameters obtained in a previous study were compared with those obtained in this work. Moreover, the direction of parameter value changes during caries formation was checked, and also compared with earlier results. The results show that Raman maps permit the determination of local variations in the enamel structure affected by the early demineralization process. As follows from these and previous results a few parameters such as depolarization ratio, polarization anisotropy, position, intensity and full width at half maximum of the Raman band allow for the identification of the enamel caries changes. This investigation contributes to the development of Raman spectroscopy for the identification of caries at a stage before visual changes in enamel.