Abstract
Objectives: This study examined the effect of one-bottle adhesives with different acidities on bonding to chemical-cured and light-cured resin composites. Methods: Twenty-four non-carious human third molars were divided into eight groups. A flat dentin surface was created for each tooth. Acid-conditioned dentin surfaces were bonded with Prime&Bond NT (Dentsply), OptiBond SOLO (Kerr), Single Bond (3M) or One-Step (Bisco). Each adhesive group was covered with composite buildups, using either a light-cured (Z100, 3M) or a chemical-cured composite (BisFil 2, Bisco). Specimens were vertically sectioned into 0.9 × 0.9 mm beams. Microtensile bond strengths were recorded and failure modes were classified using a stereoscopical microscope. Four representative beams from each group were further prepared for SEM examination. Results: Two-way ANOVA showed that the effect of adhesive types, composite curing modes and their interaction were statistically significant (P < 0.001). Multiple comparison tests revealed no statistically significant difference in the bond strength of the four adhesives with the light-cured composite (P > 0.05). However, they were significantly lower when used with the chemical-cured composite (P < 0.01). A positive correlation was observed between the acidity of adhesives and the bond strengths of the chemical-cured composite. Failure occurred predominantly along the composite-adhesive interface, with microporosities on the adhesive surface and voids within the chemical-cured composite. Significance: Air incorporated during mixing of chemical-cured composites only contributed partially to the decreased bond strength observed in simplified-step adhesives. Ultrastructural observations suggested the presence of a surface interaction between the uncured, acidic resin monomers from the oxygen inhibition layer of the adhesive and the initiator components in the chemical-cured composite.
Original language | English (US) |
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Pages (from-to) | 542-556 |
Number of pages | 15 |
Journal | Dental Materials |
Volume | 17 |
Issue number | 6 |
DOIs | |
State | Published - Nov 2001 |
Externally published | Yes |
Keywords
- Acidity
- Chemical-cured composites
- Light-cured composites
- Microtensile bond strength
- One-bottle adhesives
- SEM
ASJC Scopus subject areas
- Materials Science(all)
- Dentistry(all)
- Mechanics of Materials