Shear Bond Strength of Self-Etching Adhesive Systems to Er:YAG Laser-Prepared Dentine with and without Pulpal Pressure Simulation

This is a copy of an article published in the Photomedicine and Laser Surgery © 2008 copyright Mary Ann Liebert, Inc.; Photomedicine and Laser Surgery is available online at: http://www.liebertonline.comInternational audienceObjective: This study was conducted to study the role of pulpal pressure on the shear bond strength of composite resin bonded to Er:YAG laser-prepared or bur-prepared dentine surfaces using a self-etching adhesive system. Materials and Methods: The occlusal surfaces of 80 human third molars were ground flat to expose the dentine. The dentine was prepared using either a carbide bur or an Er: YAG laser at 350 mJ/pulse and 10 Hz (fluence 44.5 J/cm(2)). Clearfil SE Bond was then applied with or without pressure. Rods of composite resin were bonded to dentine surfaces and shear bond tests were carried out. Results: When the Clearfil SE Bond was used without pressure, the difference between the shear bond strength values of bur-prepared and laser-prepared dentine surfaces was significant. When the Clearfil SE Bond was used with pressure, the difference of shear bond strength values was not significant between the two types of surface preparation. Conclusion: The absence of smear layer formation during the preparation of the dentine by the Er: YAG laser did not improve the adhesion values of self-etching adhesive systems

Utilisation d'un nouveau matériau de coiffage pulpaire (la Biodentine )

NICE-Antenne de St Jean d'Angely (060882105) / SudocNICE-BU Médecine Odontologie (060882102) / SudocSudocFranceF

Les adhésifs automordançants sont-ils plus adaptés à la surface dentinaire préparée avec le laser Er : Yag ? (étude in vitro et sous pression trans-dentinaire)

Notre étude se propose d évaluer les interactions entre trois types d adhésifs automordançants (le CSE Bond, le XenoIII et le iBOND) et le substrat dentinaire préparé au laser Er : YAG ou à la fraise. Les surfaces préparées avec le laser ont été analysées en microscopie optique, électronique à balayage et en XPS. Nous avons ensuite étudié les interactions entre ces trois adhésifs automordançants et le substrat. Nos études de mouillabilité ont montré que la surface préparée au laser est plus hydrophile et poreuse que la surface fraisée. Les monomères acides des adhésifs automordançants sont eux aussi hydrophiles et pénètrent plus rapidement sur la surface préparée au laser. Un essai mécanique de cisaillement avec pression trans-dentinaire a ensuite été conçu de manière à évaluer l adhérence du joint dentinaire collé. L adhérence sur surface fraisée s est avérée statistiquement équivalente à celle de la surface préparée au laser pour le Xeno III et supérieure pour les deux autres. Le CSE bond présente les meilleurs résultats sur les deux types de surfaces. Les essais de cisaillement réalisés sur le CSE Bond avec pression ont montré des valeurs d adhérence comparativement plus faibles sur surfaces fraisées alors qu elles restaient équivalentes sur surfaces préparées au laser. La présence de boue dentinaire sur surface fraisée tend à favoriser l adhérence d adhésifs chargés. Cependant, le collage sur une surface propre et préparée au laser, avec ou sans pression trans-dentinaire, est plus reproductible que celui obtenu sur une surface fraisée recouverte de boue dentinaire.The goal of this study is to estimate the interactions between three self etching adhesive systems (CSE Bond, Xeno III and iBond) and dentin prepared using either burr or Re : YAG laser. Optica microscopy, SEM and XPS have been used to characterize lased surfaces. We have then studied the interactions between these three self etching adhesive systems and the substrate. Wettability studies have shown that lased surfaces were more absorbents and porous than burred surfaces. The self etching acid monomers are also absorbents and penetrate faster in lased surfaces. We have then set up a mechanical shearing test in order to evaluate the shearing strength of the bond. Shearing strength seems to be higher on burred surfaces than on lased surfaces. However these in vitro results are obtained on a dry surface which is not really physiological. We have thus adapted the device in order to generate a trans-dentinal pressure using demineralised water. With pressure, CSE Bond shearing strengths appeared to be comparatively lower on burred surfaces but remained equivalent on lased surfaces. We have also carried out a study of resin tags for the three self etching adhesive systems and for the two preparation techniques. The smear layer presence on burred surfaces seems to improve the bonding strength of filled adhesive resin. However these bonding strength measurements on a clean and lased surface with or without trans-dentinal pressure are more reproductive than for a burred surface with smear layer.NICE-BU Sciences (060882101) / SudocSudocFranceF

L 'hypersensibilité dentinaire (étiologies, mécanismes et traitements)

NICE-Antenne de St Jean d'Angely (060882105) / SudocNICE-BU Médecine Odontologie (060882102) / SudocSudocFranceF

Determination of the filler-matrix interface strength of dental composites from bending tests

International audienc

Finishing and polishing effects of multiblade burs on the surface texture of 5 resin composites: microhardness and roughness testing

International audienc

Role of surface tension and roughness on the wettability of Er: YAG laser irradiated dentin: In vitro study

International audienceIntroduction: The aim of this "in vitro" study was to evaluate the role of surface tension and surface roughness in the wettability, considered essential for a good adhesion, comparing Er:YAG laser - to bur-prepared dentin. Materials and Methods: Dentin surfaces of third human molars were Er:YAG laser- and bur-prepared to evaluate the effects of surface tension and roughness on wettability and interferometric analysis was used to compare the roughness of the two groups surfaces, after gold-coating them. Results: In bur-prepared samples the time taken for the water drop to spread out was approximately the same with or without metallization while, in the Er:YAG laser-prepared surfaces the spreading-out time was less than 10 seconds but longer after metallization i.e. nearly two minutes. Large differences in wettability measurements were observed because the water drop was almost immediately absorbed on the Er:YAG laser-prepared surface. The wettability test demonstrated that the porous and hydrophilic properties of Er:YAG laser-prepared surfaces are higher than bur-prepared surfaces. Conclusion: Surface tension, surface morphology and porosity had different effects on the spreading time of a water drop on both Er:YAG laser- and bur-prepared surfaces. And, while surface tension does not seem to influence the results, roughness appears to be the main parameter involved in water drop spreading, this being an indication, by the clinical point of view, to the choice of Er:YAG laser parameters in conservative dentistry

A numerical, theoretical and experimental study of the effect of thermocycling on the matrix-filler interface of dental restorative materials

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Theoretical prediction of dental composites yield stress and flexural modulus based on filler volume ratio

International audienc