Репозиторий Университета

© 2020 Elsevier Ltd The objective was to state zinc contribution in the effectiveness of novel zinc-doped dentin cements to achieve dentin remineralization, throughout a literature or narrative exploratory review. Literature search was conducted using electronic databases, such as PubMed, MEDLINE, DIMDI, Embase, Scopus and Web of Science. Both zinc-doping silicate and hydroxyapatite-based cements provoked an increase of both bioactivity and intrafibrillar mineralization of dentin. Zinc-doped hydroxyapatite-based cements (oxipatite) also induced an increase in values of dentin nano-hardness, Young's modulus and dentin resistance to deformation. From Raman analyses, it was stated higher intensity of phosphate peaks and crystallinity as markers of dentin calcification, in the presence of zinc. Zinc-based salt formations produced low microleakage and permeability values with hermetically sealed tubules at radicular dentin. Dentin treated with oxipatite attained preferred crystal grain orientation with polycrystalline lattices. Thereby, oxipatite mechanically reinforced dentin structure, by remineralization. Dentin treated with oxipatite produced immature crystallites formations, accounting for high hydroxyapatite solubility, instability and enhanced remineralizing activity.

© 2020 Elsevier Ltd The objective was to state zinc contribution in the effectiveness of novel zinc-doped dentin cements to achieve dentin remineralization, throughout a literature or narrative exploratory review. Literature search was conducted using electronic databases, such as PubMed, MEDLINE, DIMDI, Embase, Scopus and Web of Science. Both zinc-doping silicate and hydroxyapatite-based cements provoked an increase of both bioactivity and intrafibrillar mineralization of dentin. Zinc-doped hydroxyapatite-based cements (oxipatite) also induced an increase in values of dentin nano-hardness, Young's modulus and dentin resistance to deformation. From Raman analyses, it was stated higher intensity of phosphate peaks and crystallinity as markers of dentin calcification, in the presence of zinc. Zinc-based salt formations produced low microleakage and permeability values with hermetically sealed tubules at radicular dentin. Dentin treated with oxipatite attained preferred crystal grain orientation with polycrystalline lattices. Thereby, oxipatite mechanically reinforced dentin structure, by remineralization. Dentin treated with oxipatite produced immature crystallites formations, accounting for high hydroxyapatite solubility, instability and enhanced remineralizing activity.

© 2018 by the authors. The aim of the study was to investigate the effects of several decalcifying agents used as irrigant solutions in endodontic treatment on collagen and mineral components of dentin. Coronal dentin discs from five caries-free human third molars with a smear layer were treated for one minute with a chelating solution (1% Ethylenediaminetetraacetic acid (EDTA), 10% EDTA, 17% EDTA, 10% citric acid). Mineralization degree (Ca/N and P/N atomic ratios, IR Iapatite/Iamide II and I1410(carbonate)/I554(phosphate) spectroscopic ratios) and possible collagen rearrangements (collagen infrared (IR) amide II e III shifts) were evaluated by environmental scanning electron microscopy (ESEM)/energy dispersive X-ray spectroscopy (EDX) and IR spectroscopy before and after treatment (T0) and after ageing (T24h and T2m) in simulated body fluid (SBF). At T0, analysis showed that the highest demineralizing effect was achieved using a 10% citric acid solution and 10% EDTA, while the smallest effect was observed when using 17% EDTA. No significant collagen modifications were detected upon treatment with 1% EDTA, while subtle changes were observed after the other treatments. At T24h or T2m, analyses showed the highest remineralization values for 1% EDTA and the lowest for 10% citric acid, mainly at T2m. The samples treated with 17% EDTA showed slight collagen rearrangements upon remineralization. In conclusion, the highest demineralizing effect was observed for 10% EDTA and 10% citric acid. Collagen rearrangement was found for all the treatments except for 1% EDTA. The highest remineralization capability in SBF values was recorded for 1% EDTA and the lowest for 10% citric acid. A slight collagen rearrangement upon remineralization was still present in 17% EDTA-treated samples. Clinical use as a chelating agent in the endodontic therapy of citric acid and concentrated EDTA solutions should be reconsidered.

© 2019 Elsevier B.V. This study aimed at evaluating the remineralization effect promoted by different bioactive fillers on simulated early caries lesions in enamel (ECLE). Forty sound bovine incisors were used to prepare buccal enamel specimens (6 × 6 × 2 mm). The specimens were divided into two areas (3 × 3 mm²): control (CTR) and experimental (EXP). All the enamel specimens were then submitted to a specific protocol for a period of 48 h to induce simulated caries lesions. Subsequently, the specimens were treated for 7 days (2 min, twice a day) with a slurry pastes containing different bioactive particles (P/L ratio: 1 g/mL). All the specimens were analyzed by laser speckle before and after treatments. The results showed after the first analysis that the ECLE had very low average intensity (back-scattered light). Conversely, after application of the bioactive pastes, higher average intensity was always detected; this was comparable to CTR sound specimens. In conclusion, innovative pastes/gels developed for enamel remineralization should contain bioactive particles that when applied daily on early caries lesions may “boost” the remineralization process to reestablish a sound enamel.

© 2019 American Association of Endodontists Introduction: Pulp stones are mineral structures that develop in the pulp tissue triggered by several clinical conditions. The exact biochemical process behind the occurrence of pulp stones is uncertain. This study aimed to perform a structural and crystallographic characterization of pulp stones and dentin from extracted human teeth. Methods: The sample consisted of 13 erupted and unerupted permanent human teeth diagnosed with pulp stones. The teeth were analyzed with scanning electron microscopy with secondary and backscattered electrons, energy-dispersive spectroscopy, micro-Raman spectroscopy, micro–X-ray diffraction, and inductively coupled plasma atomic emission spectroscopy. Results: The pulp stones revealed a heterogeneous morphology and structure compared with each other. Compared with the adjacent dentin, the pulp stones had a similar structure. From a chemical point of view, oxygen, calcium, carbon, and phosphorus were the most prevalent chemical elements in the inner part of the stones, whereas on the surface carbon, nitrogen, sulfur, chlorine, aluminum, potassium, zinc, copper, and lead were the most prevalent. Copper, iron, and zinc were higher in the stones than the dentin (P < .05). Statistically significant differences between the chemical structure of stones from erupted and unerupted teeth were not detected (P > .05). Conclusions: Pulp stones have structural and chemical properties that are similar to dentin. Variations in morphology are common.

The purpose of the study was to assess the impact of toothpastes containing hydroxyapatite and fluoride on enamel caries resistance and remineralization rate. Study groups comprised 160 patients divided in 2 groups of 80 patients: 40 - at the age of 15-17 and 40 at the age of 18-25 who have been using toothpastes with hydroxyapatite and fluoride during 1 year. The plaque determination was carried out with the use of OHI-S and Turesky indexes. Litmus test pieces were used to determine oral fluid pH. The clinical determination of enamel remineralization rate, dynamics of acid resistance of enamel were carried out. Oral hygiene at baseline examination was poor in both groups. After oral hygiene training, there was a tendency towards indexes decrease more pronounced in the 18-25 age group regardless of the composition of the toothpastes used. Mean baseline oral fluid pH in the observation group was 6.5±0.4, in the comparison group - 6.8±0.4. By the end of the trial there was a tendency towards the increase of the oral fluid pH, which were 7.3±0.3 and 7.7±0.3, respectively. The enamel acid resistance of the patients of the observation group was significantly higher (p>0.05) compared with the group of patients using fluoride toothpaste, as well as the proportion of patients in whom the enamel recovery occurred within 24 hours (47.5% vs. 22.5%, respectively).

The purpose of our study was to assess the efficiency of toothpaste 'Intensive strengthening of supersensitive teeth with nano-GAP' INNOVA and the suspension 'Liquid Enamel' INNOVA on the sensitivity of teeth with gingival recession. We examined 40 people aged 20-25 years. Each group consisted of 20 people: 10 women, 10 men. The first group (observations) used the paste and the suspension for 14 days, and the second group (comparisons) cleaned teeth only with a brush without a paste. Schiff aerial test was performed to assess the rate of hypersensitivity. As a result of the study, it was found that the combination of paste and liquid suspension with nano-hydroxyapatite for 14 days effectively reduced the hypersensitivity of the teeth with gingival recession that was shown by a statistically significant decrease in the Schiff index in the observation group. Thus, this combination is the method of choice in the treatment of hyperesthesia and can be used as an alternative substitute therapy.

© 2018 Publishing House of the Union of Pediatricians. All rights reserved. A calcium deficiency is detected in more than 80% of children. This is the result of inadequate consumption of milk and dairy products which are the main food sources of calcium. There is a correlation between deficiency of calcium intake with food in childhood and the risk of osteopenia and osteoporosis in subsequent life periods. With insufficient exogenous intake of calcium, its concentration in the blood decreases which stimulates bone resorption. The factors that further limit the consumption of dairy products are lactase deficiency and cow's milk protein allergy. In order to ensure the intake of the necessary amount of calcium, it is advisable to use vitaminmineral complexes in children that contain not only a sufficient amount of calcium and Vitamin D but also other micronutrients required for bone formation.