title: The influence of temperature of three adhesive systems on bonding to ground enamel.
abstract: This study evaluated the microtensile bond strength test (pT), micromorphology of resin-enamel interface (RET) and etching patterns (EP) promoted by the etch-and-rinse adhesive, Prime&Bond NT (PB), and two self-etching adhesives, Clearfil SE Bond (SE) and Adper Prompt L-Pop (APR), to ground bovine enamel surfaces, when applied at temperatures of 5 degrees C (C), 40 degrees C (H) and 20 degrees C (R). MATERIALS AND METHODS. Sixty-three bovine incisors were randomly divided into nine experimental groups (n = 7) according to adhesive systems and temperatures. The buccal enamel surfaces were flattened with 600-grit SiC paper and abraded with a diamond bur under water-cooling. The adhesive systems were applied according to the manufacturer's instructions. After the restorative procedures, the specimens were sectioned into five slabs. Four slabs were prepared for pT and one for interface analysis. For etching pattern analysis, the remaining 16 bovine enamel fragments were used (n = 2). The adhesives were applied and the surfaces were rinsed with organic solvents after application. The specimens for RET and EP analysis were prepared for SEM analysis.
  
  
  RESULTS
  No significant differences among the adhesives were found at R temperature. However, at 5 degrees C, PB and APR presented lower bond strength than SE. At H temperature, higher bond strength was observed for PB than for APR and SE. At C and H temperature, formation of the interdiffusion zone was impaired and the treated enamel surfaces presented an undefined EP.
  
  
  CONCLUSIONS
  The variation of temperature of bonding agents affected microT, RET and EP for all materials tested.
authors.affiliation: Department of Restorative Dentistry, Piracicaba Dental School, UNICAMP, Piracicaba, Brazil. rodrigos.alexandre@yahoo.com.br
authors.forename: Rodrigo Sversut
authors.initials: RS
authors.lastname: de Alexandre
authors.forename: Renato H
authors.initials: RH
authors.lastname: Sundfeld
authors.forename: Marcelo
authors.initials: M
authors.lastname: Giannini
authors.forename: José Roberto
authors.initials: JR
authors.lastname: Lovadino
mesh_terms: D000134:Acid Etching, Dental; D000818:Animals; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D002417:Cattle; D003080:Cold Temperature; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry*; D003743:Dental Enamel / Q000648:ultrastructure*; D006358:Hot Temperature; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011109:Polymethacrylic Acids / Q000737:chemistry; D011897:Random Allocation; D019279:Resin Cements / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength
chemical_list: D017554:Carbon Compounds, Inorganic; C438313:Clearfil SE Bond; D003738:Dental Cements; D011109:Polymethacrylic Acids; C425843:Prime and Bond NT; C408584:Prompt L-Pop; D019279:Resin Cements; D017655:Silicon Compounds; C022088:silicon carbide