Bonding Failure is Similar if Brackets are Bonded Either With Resin-Modified Glass Ionomer Cements (RM-GICs) or Composite Resin Cements (CRCs)

ABSTRACTThe risk of dental caries increases with the use of orthodontic appliances, and it does not only depend on a patient's oral hygiene. Caries cause teeth enamel demineralization close to the orthodontic bracket. The hardness of the teeth consequently decreases, and they become brittle and loose. The type of adhesive used to fix brackets may or may not reduce enamel demineralization. Previous studies have shown that a resin-modified glass ionomer (RMGI) inhibits demineralization. The purpose of this work is to evaluate the effect of a fluoride-releasing bracket on mechanical properties of dentin and enamel on regions adjacent to orthodontic brackets bonded with RMGI and composite resin cements. The remineralization effect due to fluoride on teeth was assessed by measuring hardness and reduced elastic modulus on dentin, enamel and dentin-enamel junction (DEJ) around the bracket area by nanoindentation methods. Nanoindentation was performed using a TriboScope from Hysitron. For this purpose two sets of polished samples were prepared: one sample was a cut along a longitudinal section and the other one along a cross-section of a tooth with orthodontic treatment using RMGI. Anisotropy in the mechanical properties of the teeth is observed along each direction.

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Retention of oral microorganisms on conventional and resin-modified glass-ionomer cements

Pesquisa Odontológica Brasileira ◽

10.1590/s1517-74912001000300004 ◽

2001 ◽

Vol 15 (3) ◽

pp. 196-200 ◽

Cited By ~ 6

Author(s):

Denise PEDRINI ◽

Elerson GAETTI-JARDIM JÚNIOR ◽

Andréia Coelho de VASCONCELOS

Keyword(s):

Composite Resin ◽

Mutans Streptococci ◽

Microbial Colonization ◽

Glass Ionomer Cements ◽

Glass Ionomer ◽

Predisposing Factor ◽

Secondary Caries ◽

Filling Materials ◽

Resin Modified Glass Ionomer

Secondary caries are a worldwide public and socioeconomic problem. The placement of restorations can lead to the development of environmental conditions favorable to microbial colonization, especially on the tooth/restoration interface, which is a predisposing factor for secondary caries. The aim of this study was to evaluate microbial retention on conventional (Chelon-Fil and Vidrion R) and resin-modified (Vitremer and Fuji II LC) glass-ionomer cements, in situ, using a hybrid composite resin (Z100) as a control. Twelve volunteers wore Hawley appliances with specimens made of all tested filling materials for 7 days. The specimens were then removed from the appliances and transferred to tubes containing 2.0 ml of Ringer-PRAS. Microorganisms from the samples were inoculated onto blood agar and Mitis Salivarius Bacitracin agar and incubated under anaerobiosis (90% N2, 10% CO2), at 37°C, for 10 and 2 days, respectively. The resin-modified glass-ionomer cements and the composite resin retained the same levels of microorganisms on their surfaces. The resin-modified glass-ionomers retained less mutans streptococci than the composite resin and conventional glass-ionomer cements. The conventional glass-ionomer cements retained less mutans streptococci than the composite resin, but that difference was not statistically significant.

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In Vitro Bonding Performance of Modern Self-Adhesive Resin Cements and Conventional Resin-Modified Glass Ionomer Cements to Prosthetic Substrates

Applied Sciences ◽

10.3390/app10228157 ◽

2020 ◽

Vol 10 (22) ◽

pp. 8157

Author(s):

Encarna Piquer Maño ◽

Rafael Marco Algarra ◽

Amr Fawzy ◽

Vicente C. B. Leitune ◽

Fabrício M. Collares ◽

...

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Glass Ionomer Cement ◽

Glass Ionomer Cements ◽

Glass Ionomer ◽

Resin Cements ◽

Adhesive Resin ◽

Resin Modified Glass Ionomer ◽

Modern Self ◽

Ionomer Cement

This study aimed at evaluating the shear bond strength (SBS) of modern self-adhesive resin cements and resin-modified glass ionomer cements applied to different prosthetic substrates. Zirconia, lithium-disilicate glass-ceramic and a noble metal alloy were used as bonding substrates. They were all sand-blasted with alumina, while LD was further etched with 9.6% hydrofluoric acid (10 s). A light-curing resin-modified glass ionomer cement (3M-GIC: Ketac Cem Plus) and a self-curing resin-modified glass ionomer cement (GC-GIC: FujiCEM 2) were compared to self-adhesive resin cements (PAN: Panavia SA Universal) and (3M-RES: Rely X Unicem 2). Ten specimens for each substrate were produced and up to five cylinders of each cement were bonded to each substrate. The shear bond strength (SBS) was evaluated after 24 h or after thermocycling (TC) aging (5000 cycles). The data was statistically analysed by two-way ANOVA and Student–Newman–Keuls test (α = 0.05). Failure modes were analysed through stereoscopic microscopy. The greatest SBS was attained with PAN, whilst 3M-GIC showed the lowest SBS and failed prevalently in adhesive mode. No difference in SBS was observed between GC-GIC and 3M-RES. After TC aging, all cements showed significant drop (p < 0.05) in SBS, but PAN showed the greatest SBS. Reliable bond strength to prosthetic substrates can be achieved with specific universal resin-luting cements and may be an alternative to glass ionomer cements when luting alloy substrates.

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Effect of Fluoride on Mechanical Properties of Teeth Demineralized by Use of Orthodontic Appliances

MRS Proceedings ◽

10.1557/proc-844-y3.3/r3.3 ◽

2004 ◽

Vol 844 ◽

Author(s):

Claudia Centeno ◽

Ulises Ruiz ◽

Oscar Contreras ◽

Enrique C. Samano

Keyword(s):

Mechanical Properties ◽

Cross Section ◽

Composite Resin ◽

Longitudinal Section ◽

Orthodontic Appliances ◽

Glass Ionomer ◽

Resin Cements ◽

Orthodontic Bracket ◽

Enamel Demineralization ◽

Resin Modified Glass Ionomer

ABSTRACTThe risk of dental caries increases with the use of orthodontic appliances, and it does not only depend on a patient's oral hygiene. Caries cause teeth enamel demineralization close to the orthodontic bracket. The hardness of the teeth consequently decreases, and they become brittle and loose. The type of adhesive used to fix brackets may or may not reduce enamel demineralization. Previous studies have shown that a resin-modified glass ionomer (RMGI) inhibits demineralization. The purpose of this work is to evaluate the effect of a fluoride-releasing bracket on mechanical properties of dentin and enamel on regions adjacent to orthodontic brackets bonded with RMGI and composite resin cements. The remineralization effect due to fluoride on teeth was assessed by measuring hardness and reduced elastic modulus on dentin, enamel and dentin-enamel junction (DEJ) around the bracket area by nanoindentation methods. Nanoindentation was performed using a TriboScope from Hysitron. For this purpose two sets of polished samples were prepared: one sample was a cut along a longitudinal section and the other one along a cross-section of a tooth with orthodontic treatment using RMGI. Anisotropy in the mechanical properties of the teeth is observed along each direction.

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