Dry-bonding to dentin using alternative conditioners based on iron-containing solutions or nitric acid.
J Mech Behav Biomed Mater
; 94: 238-248, 2019 06.
Article
em En
| MEDLINE
| ID: mdl-30927591
ABSTRACT
OBJECTIVES:
To evaluate the effect of experimental conditioners (10-3 solution - 10-3, 6.8% ferric oxalate - FOX, and 1.4% nitric acid - NI) on dentin elastic modulus, flexural strength, bond strength, failure mode, and adhesive interface morphology of two etch-and-rinse adhesives (XP Bond, Dentsply or One-Step, Bisco) applied on etched dry dentin.METHODS:
Sound human third molars were used for the microtensile bond strength test (nâ¯=â¯8), performed at 24â¯h and after one year of water storage. Failure modes were evaluated by scanning electron microscopy. Dentin bonding interface was analyzed by confocal laser scanning microscopy (nâ¯=â¯3). Adhesive systems were applied on phosphoric acid-etched, wet (positive control) and dry (negative control) dentin, and on etched and dry dentin previously treated with 10-3 (15s), FOX (60s), or NI (15s). Bovine dentin bars (nâ¯=â¯15) were immersed into the conditioning solutions and subjected to a three-point bending test.RESULTS:
XP Bond +â¯10-3 or NI resulted in lower bond strength than phosphoric acid. One-Step +â¯10-3 or NI resulted in bond strengths equivalent to the positive control. Experimental conditioners presented no bond strength reduction after one year, regardless of the bonding agent tested. One-Step resulted in more adhesive failures than XP Bond at 24â¯h, and mixed failures increased after storage. All experimental conditioners promoted hybridization and resin tags formation, except FOX. Dentin elastic modulus was not affected by the conditioners, whereas flexural strength was significantly reduced by FOX.CONCLUSIONS:
Adequate and stable dentin bonds were achieved when the bonding agents were applied on 10-3 or NI-treated dentin. None of the experimental conditioners reduced dentin elastic modulus, but dentin flexural strength was significantly reduced by FOX-conditioning.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Ácido Nítrico
/
Dentina
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Ferro
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article