Microbiological or chemical models of enamel secondary caries compared by polarized‐light microscopy and energy dispersive X‐ray spectroscopy

Abstract

Different secondary caries models may present different results. The purpose of this study was to compare different in vitro secondary caries models, evaluating the obtained results by polarized-light microscopy (PLM), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS). Standardized human enamel specimens (n = 12) restored with different materials (Z250 conventional composite resin-CRZ, Freedom polyacid-modified composite resin-CRF, Vitremer resin-modified glass-ionomer-GIV, and Fuji IX conventional glass-ionomer cement-GIF) were submitted to microbiological (MM) or chemical caries models (CM). The control group was not submitted to any caries model. For MM, specimens were immersed firstly in sucrose broth inoculated with Streptococcus mutans ATCC 35688, incubated at 37 degrees C/5% CO(2) for 14 days and then in remineralizing solution for 14 days. For CM, specimens were submitted to chemical pH-cycling. Specimens were ground, submitted to PLM and then were dehydrated, gold-sputtered and submitted to SEM and EDS. Results were statistically analyzed by Kruskall-Wallis and Student-Newman-Keuls tests (alpha = 0.05). No differences between in vitro caries models were found. Morphological differences in enamel demineralization were found between composite resin and polyacid-modified composite resin (CRZ and CRF) and between the resin-modified glass-ionomer and the glass-ionomer cement (GIF and GIV). GIF showed higher calcium concentration and less demineralization, differing from the other materials. In conclusion, the glass-ionomer cement showed less caries formation under both in vitro caries models evaluated.

Chemical and crystallographic study of remineralized surface on initial carious enamel treated with Galla chinensis

“…According to Kielbassa et al, EDS provides a semiquantitative technique for analyzing a cariesaffected surface, allowing chemical surface variation to be monitored (Kielbassa et al 2006). In this study, the results obtained by EDS regarding Ca %wt of DDW-treated carious enamel were similar to those of carious enamel reported by Paradella et al (2008Paradella et al ( , 2009). However, the Ca %wt was lower than that from Aires et al and Moshonov et al (Aires et al 2006;Moshonov et al 2005).…”

“…Bovine enamel has been widely used in demineralization and remineralization experiments, since it is easier to obtain and to perform experiments on (Attin et al 2007). Incisors from 4-yearold cows were used to avoid the effect of the variation of chemical composition and crystal structure in different tooth types and age (Paradella et al 2009;Waidyasekera et al 2007). Furthermore, since the surface microhardness can reect the mineral content of tooth, and the microhardness value is line-related with the mineral content (Kielbassa et al 1999), the microhardness value was chosen to control the base line consistency of carious enamel samples in this study, only the samples with KHNs between 275.15 and 341.87 were chosen for the remineralization treatment.…”

Degree of Conversion and Hardness of Two Different Systems of the VitrebondTM Glass Ionomer Cement Light Cured with Blue LED

“…The RMGICs are commonly used in dentistry due to the properties, such as fluoride released, biocompatibility, low shrinkage, thermal compatibility and less caries formation [1][2][3][4][5][6][7][8][9][10] with tooth becoming an important material for studying. The hardness is one of most important physical properties to dental materials that can evaluate the resistance by indentation.…”

“…These materials have been commonly used due to the properties of fluoride release with a potential reduction in secondary caries, thermal compatibility with tooth enamel and dentin, minimized microleakage at the modulus of elasticity similar to dentin, tooth-enamel interface due to low shrinkage and low cytotoxicity. [1][2][3][4][5][6][7][8][9][10] The GIC sets via an acid-base reaction between calcium and/or aluminum cations released from a reactive glass and carboxyl anions pendent on polyacid. The polymer backbones of GIC has been by poly (acrylic acid) homopolymer, poly (acrylic acid-co-itaconic acid) or/and poly (acrylic acid-co-maleic acid) copolymers.…”

Sensing of Tooth Microleakage Based on Dental Optical Coherence Tomography

“…However, no matter what treatment is used, patients are at risk for secondary caries. The Federation Dentaire Internationale defines secondary caries as positively diagnosed carious lesions that occur at the margins of an existing restoration [6]. This is an important clinical problem; it reduces the lifetime of dental restorations, alters dental hard tissue, and endangers tooth survival [7].…”