title: Effect of gamma irradiation on fluoride release and antibacterial activity of resin dental materials.
abstract: This study evaluated the effect of gamma irradiation on fluoride release and antibacterial activity of FluroShield (FS) and Clearfil Protect Bond (CPB). Four groups were formed: G1-FS + gamma; G2-FS without gamma; G3-CPB + gamma; G4-CPB without gamma. For fluoride release analysis, 12 disks of each material were prepared and covered with nail polish, except for one side (50.4 mm(2) area). G1 and G3 were sterilized with a 14.5 KGy dose at 27 degrees C for 24 h, while G2 and G4 (controls) were not sterilized and were maintained under the same time and temperature conditions. Fluoride release measurements were made in duplicate (n=6) by an ion specific electrode. The antibacterial activity of the CPB and FS against Streptococcus mutans after gamma sterilization was evaluated by the agar-disc diffusion method. The diameter of the zones of microbial growth inhibition was recorded after 48 h. Data were analyzed statistically by ANOVA and Tukey's test (alpha=5%). Gamma sterilization decreased the fluoride release of FS by approximately 50%, while CPB was not affected. There was no statistically significant difference (p>0.05) in the antibacterial effect of CPB between gamma and non-gamma sterilization groups. FS presented no antibacterial activity. Gamma irradiation decreased the fluoride release of FS, but did not affect the antibacterial activity of the studied materials.
authors.affiliation: Department of Dental Materials, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil.
authors.forename: Fabíola Galbiatti de
authors.initials: FG
authors.lastname: Carvalho
authors.forename: Suzana Beatriz Portugal de
authors.initials: SB
authors.lastname: Fucio
authors.forename: Fernanda Miori
authors.initials: FM
authors.lastname: Pascon
authors.forename: Kamila Rosamilia
authors.initials: KR
authors.lastname: Kantovitz
authors.forename: Lourenço
authors.initials: L
authors.lastname: Correr-Sobrinho
authors.forename: Regina Maria
authors.initials: RM
authors.lastname: Puppin-Rontani
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry / Q000528:radiation effects; D002327:Cariostatic Agents / Q000032:analysis*; D017220:Dentin-Bonding Agents / Q000737:chemistry / Q000528:radiation effects*; D052978:Disk Diffusion Antimicrobial Tests; D005459:Fluorides / Q000032:analysis*; D005720:Gamma Rays; D017736:Ion-Selective Electrodes; D010895:Pit and Fissure Sealants / Q000737:chemistry / Q000528:radiation effects*; D011140:Polyurethanes / Q000737:chemistry / Q000528:radiation effects; D011726:Pyridinium Compounds / Q000737:chemistry / Q000528:radiation effects; D019279:Resin Cements / Q000737:chemistry / Q000528:radiation effects*; D012117:Resins, Synthetic / Q000737:chemistry / Q000528:radiation effects*; D013242:Sterilization / Q000379:methods*; D013295:Streptococcus mutans / Q000187:drug effects*
chemical_list: D002327:Cariostatic Agents; C503075:Clearfil Protect Bond; D017220:Dentin-Bonding Agents; D010895:Pit and Fissure Sealants; D011140:Polyurethanes; D011726:Pyridinium Compounds; D019279:Resin Cements; D012117:Resins, Synthetic; C089392:methacryloyloxydodecylpyridinium bromide; C086661:Fluoroshield; D017438:Bisphenol A-Glycidyl Methacrylate; D005459:Fluorides