title: Influence of Er,Cr:YSGG laser treatment on microtensile bond strength of adhesives to enamel.
abstract: The current trend towards minimum-intervention dentistry has introduced laser technology as an alternative technique for cavity preparation. This study assessed the null hypothesis that enamel prepared either by Er,Cr:YSGG laser or conventional diamond bur is equally receptive to adhesive procedures. The buccal and lingual surfaces of 35 sound human molars were prepared with Er,Cr:YSGG laser or a medium-grit diamond bur. One etch&rinse (OptiBond FL) and three self-etch adhesives (Adper Prompt L-Pop, Clearfil SE Bond and Clearfil S3 Bond) were applied on laser-irradiated and bur-cut enamel, followed by the application of a 5-6 mm build-up of Z100. The micro-tensile bond strength (microTBS) was determined after 24 hours of storage in water at 37 degrees C. Prepared enamel surfaces and failure patterns were evaluated using a stereomicroscope and a field-emission-gun scanning electron microscope (Feg-SEM). The pTBS to laser-irradiated enamel was significantly lower than to bur-cut enamel (p<0.05), with the exception of Clearfil S3 Bond, which bonded equally effectively to both substrates. The latter presented the highest microTBS on laser-irradiated enamel, though it was not statistically different from the microTBS of OptiBond FL. SEM analysis revealed significant morphological alterations of the laser-irradiated enamel surface, such as areas of melted and recrystalized hydroxyapatite and deep extensive micro-cracks. In conclusion, the bonding effectiveness of adhesives to laser-irradiated enamel depends not only on the structural substrate alterations induced by the laser, but also on the characteristics of the adhesive employed.
authors.affiliation: Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Leuven, Belgium.
authors.forename: Marcio Vivan
authors.initials: MV
authors.lastname: Cardoso
authors.forename: Jan
authors.initials: J
authors.lastname: De Munck
authors.forename: Eduardo
authors.initials: E
authors.lastname: Coutinho
authors.forename: R Banu
authors.initials: RB
authors.lastname: Ermis
authors.forename: Kirsten
authors.initials: K
authors.lastname: Van Landuyt
authors.forename: Rubens Corte Real
authors.initials: RC
authors.lastname: de Carvalho
authors.forename: Bart
authors.initials: B
authors.lastname: Van Meerbeek
mesh_terms: D003188:Composite Resins / Q000737:chemistry; D003461:Crystallography; D001840:Dental Bonding; D003737:Dental Cavity Preparation / Q000295:instrumentation; D003738:Dental Cements / Q000737:chemistry*; D003743:Dental Enamel / Q000528:radiation effects / Q000648:ultrastructure*; D003793:Dental Restoration, Permanent; D017220:Dentin-Bonding Agents / Q000737:chemistry; D018130:Diamond / Q000737:chemistry; D017886:Durapatite / Q000737:chemistry / Q000528:radiation effects; D006801:Humans; D053685:Laser Therapy; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors; D014867:Water / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
chemical_list: C505694:Clearfil S3 Bond; C438313:Clearfil SE Bond; D003188:Composite Resins; D003738:Dental Cements; D017220:Dentin-Bonding Agents; C469607:OptiBond FL; C408584:Prompt L-Pop; D019279:Resin Cements; C083568:Z100 composite resin; D014867:Water; D012822:Silicon Dioxide; D018130:Diamond; D017886:Durapatite; D015040:Zirconium