title: Tensile bond strength of sealants following Er:YAG laser etching compared to acid etching in permanent teeth.
abstract: The aim of this in vitro study was to assess the effect of Er:YAG laser surface treatment on the tensile bond strength of a sealant in permanent teeth. A total of 30 sound third molars were selected and embedded in cold-cure acrylic resin. The enamel surfaces were flattened by a grinding. The teeth were randomly divided into three groups and pretreated as follows: (1) 37% phosphoric acid; (2) Er:YAG laser (1.5 ml/min water spray, 100 mJ energy output, 10 Hz frequency, focal distance 17 mm); (3) Er:YAG laser + 37% phosphoric acid. The treated surfaces were isolated by double adhesive Sellotape and after insertion of a split Teflon matrix at an isolated site, sealant was applied. The specimens were thermocycled and stored at 37°C in distilled water for 72 h, then subjected to a tensile bond strength test (50 kgf at 0.5 mm/min). The mean tensile bond strengths (± SD, in megapascals) were: 18.51 ± 5.68 in group 1, 8.06 ± 2.69 in group 2, and 17.33 ± 5.04 in group 3. Data were submitted to analysis of variance and the Tukey test. No significant difference were found between groups 1 (37% phosphoric acid) and group 3 (Er:YAG laser + 37% phosphoric acid) but treatment with the Er:YAG laser alone (group 2) resulted in significantly lower tensile bond strength than seen in the other groups. In this setting, the Er:YAG laser prepared the enamel surface for sealing but did not eliminate the need for acid etching before sealant application.
authors.affiliation: Laser Research Center in Dentistry (LRCD), Tehran University of Medical Sciences, Tehran, Iran. shahabis@tums.ac.ir
authors.forename: Sima
authors.initials: S
authors.lastname: Shahabi
authors.forename: Hossein G
authors.initials: HG
authors.lastname: Bagheri
authors.forename: Kosar
authors.initials: K
authors.lastname: Ramazani
mesh_terms: D000134:Acid Etching, Dental / Q000295:instrumentation*; D003743:Dental Enamel / Q000187:drug effects / Q000528:radiation effects*; D003764:Dental Materials / Q000737:chemistry; D019229:Dentition, Permanent; D006801:Humans; D066298:In Vitro Techniques; D053844:Lasers, Solid-State; D008964:Molar, Third / Q000187:drug effects / Q000528:radiation effects; D010756:Phosphoric Acids / Q000494:pharmacology*; D010895:Pit and Fissure Sealants / Q000494:pharmacology* / Q000528:radiation effects; D012117:Resins, Synthetic / Q000528:radiation effects*; D013718:Tensile Strength / Q000187:drug effects / Q000528:radiation effects
chemical_list: D003764:Dental Materials; D010756:Phosphoric Acids; D010895:Pit and Fissure Sealants; D012117:Resins, Synthetic; C030242:phosphoric acid