Search results for "enamel"
showing 10 items of 277 documents
Human Dental Pulp Stem Cells Exhibit Different Biological Behaviours in Response to Commercial Bleaching Products
2018
The purpose of this study was to evaluate the diffusion capacity and the biological effects of different bleaching products on human dental pulp stem cells (hDPSCs). The bleaching gel was applied for 90, 30 or 15 min to enamel/dentine discs that adapted in an artificial chamber. The diffusion of hydrogen peroxide (HP) was analysed by fluorometry and the diffusion products were applied to hDPSCs. Cell viability, cell migration and cell morphology assays were performed using the eluates of diffusion products. Finally, cell apoptosis and the expression of mesenchymal stem cell markers were analysed by flow cytometry. Statistical analysis was performed using analysis of variance and Kruskal&nda…
A swift, easy and cheap protocol to evaluate the tooth bleaching in vitro
2018
Background: This study aims to develop a protocol that optimizes in vitro dental bleaching procedures in a cheap, fast and accessible manner. Material and Methods: 18 bovine incisors were cut and polished in enamel/dentin and submitted to staining in coffee solution during 72 hours. After the standardization and staining of the enamel surfaces, three groups (n = 6) were formed to receive three different gels, WHITENESS (commercial gel); H 2 O 2 - 5% (manipulated gel); CAR - BOPOL GEL (manipulated gel and without H 2 O 2 ). The color of the enamel surfaces was evaluated using digital images, obtained with digital camera and controlled luminosity, before and after staining, as well as after e…
Correlation between micro-hardness and mineral content in healthy human enamel
2016
Background Enamel is the hardest and the stiffest tissue in the human body. The enamel undergoes multidirectional stresses, withstands multimillion chewing cycles, all while protecting the internal dentin and pulp from damage due to mechanical overload and exposure to the harsh chemical environment of the mouth. Raman spectroscopy allows to study enamel mineral content in a non-destructive and site-specific way. While Raman spectroscopy has been applied in other studies to assess tooth mineralization, there are no studies that examine the relationship between micro-hardness and mineral content of the untreated enamel. An understanding of this relationship is extremely important in a clinica…
A time based objective evaluation of the erosive effects of various beverages on enamel and cementum of deciduous and permanent teeth
2019
Background Erosion of the teeth is a chronic irreversible process leading to loss of surface enamel and even the dentin, in turn causing sensitivity and pain. Increased consumption of carbonated beverages remains a major cause for dental erosion. However, many of the so called safe beverages that are consumed may also have sufficiently low pH to cause dental erosion. One of the parameters to measure the dental erosion is estimation of hardness and surface roughness. Thus, this study aims to evaluate the difference in hardness and surface roughness of enamel and cementum using three beverages namely (carbonated drink, lime soda, lime juice) in deciduous and permanent teeth. Material and Meth…
Effect of in situ aspartame mouthwash to prevent intrinsic and extrinsic erosive tooth wear
2020
Background The aim was to evaluate whether aspartame regular mouthwash prior to erosive challenges with citric or hydrochloric acids would be able to prevent erosive enamel wear. Material and methods This randomized, single blind in situ study was conducted with 3 crossover phases of 5 days. Polished bovine enamel blocks (n=252) were randomly divided among 6 groups/ 3 phases/ 21 volunteers. The groups under study were: aspartame solution (0.024% of aspartame in deionized water - experimental group), deionized water (negative-control) and stannous-containing solution (Elmex® Erosion Protection Dental Rinse; positive-control); subjected to erosion on citric acid or hydrochloric acid. Four tim…
Caries Development in Fluoridated and Non-Fluoridated Deciduous and Permanent Enamel in Situ Examined by Microradiography and Confocal Laser Scanning…
1998
The aim of the study was to compare initial caries development in fluoridated and non-fluoridated deciduous and permanent enamel in situ. Enamel slabs were mounted in removable appliances and worn for 4 wks. Significantly larger lesions developed in deciduous than in permanent enamel when no topical fluorides were used. Fluoride mouthrinsing partly prevented lesion development in deciduous and completely in permanent enamel. Initial enamel caries not detected by microradiography can be visualized by CLSM (confocal laser scanning microscopy).
Advanced Techniques of Micro-Analysis and Confocal Microscopy: Perspectives for Studying Chemical and Structural Changes at the Interface Between Res…
1995
Migration of trace amounts of elements and structural changes characterize the interface between immiscible substances. The contact zone among filling materials, saliva, and the cavity wall has the additional function of preventing the progress of leakage and subsequent caries. Difficulties in chemically and structurally analyzing the gradients of composition in an interface of microscopic dimensions characterize the experimental situation. The use of advanced techniques of instrumental micro-analysis and techniques of micro-visualization is our approach to the problem. With confocal laser scanning microscopy (CLSM), effects of the components of the filling material on the structure of the…
Effect of rinsing time and surface contamination on the bond strength of silorane-based and dimethacrylate-based composites to enamel
2018
Background The aim of this study was to assess whether saliva contamination and rinsing time for 15, 30, and 60 seconds, affects the shear bond strength of silorane and methacrylate-based composites to enamel. Material and Methods Two light cure resin, P60 (3M ESPE) and Filtek LS Silorane were tested. 120 sound premolars were randomly divided into four groups of 30 teeth based on composite type with or without saliva contamination after etching and rinsing. Each group was further divided into three subgroups according to their rinsing time. Then a cylinder of the composite was bonded to the enamel and Shear bond strength was assessed. To determine the failure mode, the bonded surfaces were …
Applications of confocal laser scanning microscopy to dental bonding.
1998
The introduction of confocal laser scanning microscopy (CLSM) has provided a valuable new technique for the visualization of bonding structures such as a hybrid layer in dentin (Watson, 1989, 1991), In the case of seven commercially-available dentin bonding systems, it could be demonstrated that the CLSM renders considerably more detailed information than the SEM because of its nondestructive nature and because of the possibility of a distinction between components of bonding agents. With most of the bonding systems, measurements of the thickness of the hybrid layer could be carried out when the primer component was labeled with rhodamine B. It was found that this thickness is significantl…
A Novel Biomimetic Approach to Repair Enamel Cracks/Carious Damages and to Reseal Dentinal Tubules by Amorphous Polyphosphate.
2017
Based on natural principles, we developed a novel toothpaste, containing morphogenetically active amorphous calcium polyphosphate (polyP) microparticles which are enriched with retinyl acetate (“a-polyP/RA-MP”). The spherical microparticles (average size, 550 ± 120 nm), prepared by co-precipitating soluble Na-polyP with calcium chloride and supplemented with retinyl acetate, were incorporated into a base toothpaste at a final concentration of 1% or 10%. The “a-polyP/RA-MP” ingredient significantly enhanced the stimulatory effect of the toothpaste on the growth of human mesenchymal stem cells (MSC). This increase was paralleled by an upregulation of the MSC marker genes for osteoblast differ…