Search results for "Enamel"
showing 10 items of 277 documents
Feeding ecology and chewing mechanics in hoofed mammals: 3D tribology of enamel wear.
2013
11 pages; International audience; Large herbivorous mammals have evolved chewing systems capable of processing a large variety of structurally diverse foods. Three-dimensional (3D) surface texture parameters are applied to investigate wear mechanisms related to tooth morphology, food source, and chewing dynamics. We tested 46 industrial 3D surface texture parameters for their capability to robustly indicate specific biomechanics in two grazing (Blue Wildebeest and Grevy's Zebra) and two browsing (Giraffe and Black Rhinoceros) ungulate mammals. These species inhabit sub-Saharan Africa and represent foregut and hindgut fermenters. The results did not indicate a wavelength threshold that can c…
XRMA analysis and X-ray diffraction analysis of dental enamel from human permanent teeth exposed to hydrogen peroxide of varying pH
2019
Background This in vitroinvestigation shows how 3.3% H2O2, at different pH-values affects the enamel. Material and Methods A number of fifteen human premolars were used. The enamel of the coronal half in six of the teeth, were exposed by H2O2. Nine teeth were prepared to enamel powder. The enamel was exposed to 3.3% H2O2, at six different pH-values (pH range 4.5 - 7.0). Analyses of the topography of enamel performed by scanning electron microscope (SEM) and the chemical composition of enamel by X-ray microanalysis (XRMA). X-ray powder diffraction (XRD) analysed the crystallinity in enamel powder. Results The exposure to H2O2 at pH5.5 resulted in a decrease of O in the exposed enamel, and ch…
Laser-Casein phosphopeptide effect on remineralization of early enamel lesions in primary teeth
2014
Background: The aim of this study was to assess the effect of Nd:YAG laser irradiation following casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application on calcium and phosphate concentration and surface microhardness (SMH) of enamel surface in artificial white spot lesions of primary teeth. Material and Methods: Eighty teeth with artificial white spot lesions were randomly divided into four groups: (A) distilled and deionized water, (B) Nd:YAG laser, (C) CPP-ACP crème, & (D) CPP-ACP plus laser. SMH was measured using Vickers diamond indenter in Vickers Hardness Number (VHN). Two samples of each group were analyzed using scanning electron microscope (SEM). The results were a…
In vitro evaluation of the antibacterial activity of cured dentin/enamel adhesive incorporating the antimicrobial agent MDPB
2010
The aim of this study was to investigate in vitro the antibacterial effect of a dentin/enamel adhesive containing MDPB (Clearfil Protect Bond) after curing and to compare it with an adhesive not containing MDPB (Clearfil SE Bond). The antibacterial effect of the cured adhesives was tested on Enterococcus faecalis by the evaluation of growth inhibition in a 48-h microplate direct contact test (DCT). The presence of antibacterial activity due to soluble components was also investigated by an agar diffusion test (ADT) performed with the adhesives cured on the surface of dentin disks. In the DCT, both the tested materials showed complete inhibition of bacterial growth until the 7-h reading, reg…
Il mantenimento della salute orale nel paziente in trattamento ortodontico
2008
I trattamenti ortodontici vengono eseguiti con dispositivi rimovibili o fissi che, modificando l’ecosistema del cavo orale, aumentano il rischio d’insorgenza e progressione di lesioni cariose e di malattia parodontale. Pertanto, occorre attuare un protocollo individualizzato di prevenzione che preveda un adeguato addestramento all’igiene orale domiciliare, con rinforzi motivazionali nelle varie fasi del trattamento ortodontico, e l’attuazione di programmi di fluoroprofilassi topica professionale e domiciliare. Fixed or removable appliances impede the maintenance of good oral hygiene resulting in dental plaque accumulation. Plaque retention surrounding orthodontic appliances can increase the…
Eroded enamel rehardening using two intraoral appliances designs in different times of salivary exposure.
2019
Background The aim of this study was evaluated the eroded enamel rehardening potential using upper palatal and lower buccal removable appliances in different times of salivary exposure (30 min, 1h, 2h, 12h) after a single erosive challenge event. Material and Methods After initial surface hardness evaluation, bovine enamel blocks were eroded in vitro (0.01 M hydrochloric acid, pH 2.3, 30 seconds), selected (n = 160) and randomly assigned to the two appliance designs and twenty volunteers. Four enamel blocks were inserted in each removable appliance. On the in situ phase, the volunteers were instructed to use the upper palatal and lower buccal appliances simultaneously for 12 nonconsecutive …
Effect of postbleaching application of an antioxidant on enamel bond strength of three different adhesives
2010
Objectives: The aim of this study was to compare the shear bond strength (sbs) of three different adhesives on bleached enamel immmmediately after bleaching, bleached/delayed for 1 week, and bleached/applied antioxidizing agent. Study Design: The enamel surfaces of 144 freshly extracted incisors without any caries and restorations were flattened and divided into 12 groups. The following adhesives were investigated: Optibond FL (OFL) (three-step etch&rinse), Optibond Solo Plus (OSP) (two-step etch&rinse), Optibond All-in-One (OA) (one-step self-etch), (Kerr, Orange, USASA). Unbleached enamel groups were prepared as negative controls. The remainder surfaces were bleached with 20% Opalescent P…
Effect of antioxidants on the shear bond strength of composite resin to enamel following extra-coronal bleaching
2019
Background Recently patients need faster treatments, and delaying restoration is not possible following bleaching treatment. The purpose of this study was to determine the effect of antioxidants, namely 10% sodium ascorbate, 10% alpha-tocopherol, 10% green tea and 10% Aloe vera extract on the shear bond strength of composite resin to enamel following extra-coronal bleaching using 40% hydrogen peroxide. Material and Methods Seventy premolars were randomly assigned into 7 groups of 10 each. Group 1: bleaching treatment and no antioxidants application. Group 2: composite was built-up immediately after bleaching. Group 3: bleached specimens received composite build-up delayed by 2 weeks. Group …
Effect of disinfecting the cavity with chlorhexidine on the marginal gaps of Cl V giomer restorations
2017
Background Considering the effect of cavity disinfecting agents on the bonding and sealing ability of restorations bonded to dentin, the aim of this study was to evaluate the effect of chlorhexidine (CHX) disinfecting agent on the marginal gaps of Cl V giomer restorations. Material and Methods Cl V cavities were prepared on the buccal surfaces of 60 sound bovine permanent incisors in this in vitro study, with the occlusal and gingival margins in enamel and dentin, respectively. The teeth were randomly divided into two groups (n=30). The teeth in groups 1 and 2 were restored without and with the use of the disinfecting agent in the cavity, respectively, before applying the adhesive. BeautiBo…
The staining effect of different mouthwashes containing nanoparticles on dental enamel
2015
Background: This study aimed to evaluate the effects of several mouthwashes containing nanoparticles on discoloration of dental enamel, and compare the results with that of 0.2% chlorhexidine (CHX). Material and Methods: Sixty intact premolars were randomly assigned to six groups. A spectrophotometer was used to measure the color of the teeth (T1) according to the CIELAB system. The specimens in groups 1 to 4 were then immersed in colloidal solutions containing nanoTiO2 (Group 1), nanoZnO (Group 2), nanoAg (Group 3) and nanoCuO (Group 4). In groups 5 and 6, a 0.2% CHX mouthwash and distilled water were used as positive and negative controls, respectively. After 24 hours of immersion, color …