The competition between enamel and dentin adhesion within a cavity: An in vitro evaluation of class V restorations

To gain more insight into the consequences of curing contraction within the tooth cavity, we assessed the margin behavior of 12 contemporary restorative systems in class V restorations with margins located on enamel and dentin after mechanical loading and water storage. Mixed class V cavities were prepared on extracted human molars and restored using five etch and rinse and seven self-etch adhesive systems with their corresponding composites. Marginal adaptation was evaluated by using a computer-assisted quantitative marginal analysis in a scanning electron microscope (SEM) on epoxy replicas before, after thermal and mechanical stressing and after 1year of water storage. The interactions of "testing conditions”, "adhesive-composite combination” and "tooth substrate” with "marginal adaptation” were evaluated by two-way ANOVA. Fatigue, stress and storage conditions had significant effects on the marginal adaptation. Only two groups (Optibond FL and G Bond) presented equal percentages of marginal adaptation on enamel and dentin; in the other groups, the rate of degradation was product dependent. All materials tested showed a distinct behavior on enamel and dentin. In addition to mechanical resistance and long-term stability, differences within materials also exist in their ability to simultaneously bond to enamel and denti

Influence de la charge thermomécanique et de l'hydrolyse sur la dégradation marginale des systèmes adhésifs

But: évaluer et quantifier l'adaptation marginale des obturations de Classe V en composite direct au niveau de l'émail et de la dentine, ceci avant et après charge et après une année d'hydrolyse. Observer si les différents systèmes adhésifs ainsi que leur mode d'action sur leurs substrats ont une influence sur l'adaptation marginale avant et après un test de fatigue thermomécanique et après une année d'hydrolyse. Matériel et méthodes: comparer douze groupes de composites directs qui impliquent l'utilisation de systèmes adhésifs, avec ou sans l'utilisation du mordançage (acide phosphorique), au moment de leur application en une, deux ou trois étapes. L'adaptation marginale de ces obturations a été évaluée avant et après contraintes thermique et mécanique ainsi qu'après une année d'hydrolyse. Résultats: des différences significatives ont été notées entre les différents groupes concernant la continuité des marges et même au sein des mêmes groupes avant, après charge et après une année d'hydrolyse. Conclusion: aucun des adhésifs examinés ne pouvait fournir une continuité des marges dans l'émail et la dentine après les avoir soumis à une contrainte thermomécanique et au stockage dans l'eau. Les propriétés chimiques de chaque produit peuvent fortement influencer la stabilité des composants du système adhésif sous la charge et les propriétés de mouillage des produits peuvent être également importante

The competition between enamel and dentin adhesion within a cavity: an in vitro evaluation of class V restorations

To gain more insight into the consequences of curing contraction within the tooth cavity, we assessed the margin behavior of 12 contemporary restorative systems in class V restorations with margins located on enamel and dentin after mechanical loading and water storage. Mixed class V cavities were prepared on extracted human molars and restored using five etch and rinse and seven self-etch adhesive systems with their corresponding composites. Marginal adaptation was evaluated by using a computer-assisted quantitative marginal analysis in a scanning electron microscope (SEM) on epoxy replicas before, after thermal and mechanical stressing and after 1 year of water storage. The interactions of "testing conditions", "adhesive-composite combination" and "tooth substrate" with "marginal adaptation" were evaluated by two-way ANOVA. Fatigue, stress and storage conditions had significant effects on the marginal adaptation. Only two groups (Optibond FL and G Bond) presented equal percentages of marginal adaptation on enamel and dentin; in the other groups, the rate of degradation was product dependent. All materials tested showed a distinct behavior on enamel and dentin. In addition to mechanical resistance and long-term stability, differences within materials also exist in their ability to simultaneously bond to enamel and dentin

Marginal adaptation after aging of a self-etching adhesive containing an antibacterial monomer

To evaluate the marginal adaptation of mixed Class V cavities restored with Clearfil Protect Bond (Kuraray), Clearfil SE Bond (Kuraray), and two experimental combinations of both marketed adhesives, after fatigue and water storage