title: Effect of Er,Cr:YSGG Laser at Different Output Powers on the Micromorphology and the Bond Property of Non-Carious Sclerotic Dentin to Resin Composites.
abstract: BACKGROUND
  The objective of this study was to investigate the influence of Er,Cr:YSGG laser irradiated at different powers on the micromorphology and the bonding property of non-carious sclerotic dentin to resin composites.
  
  
  METHODS
  Two hundred bovine incisors characterized by non-carious sclerotic dentin were selected, and the seventy-two teeth of which for surface morphological analysis were divided into nine groups according to various treatments (A: the control group, B: only treated with the adhesive Adper Easy One, C: diamond bur polishing followed by Adper Easy One, D-I: Er,Cr:YSGG laser irradiating at 1W, 2W, 3W, 4W, 5W, 6W output power, respectively, followed by Adper Easy One). The surface roughness values were measured by the non-contact three-dimensional morphology scanner, then the surface micromorphologies of surfaces in all groups were assessed by scanning electron microscopy (SEM); meanwhile, Image Pro-Plus 6.0 software was used to measure the relative percentage of open tubules on SEM images. The rest, one hundred twenty-eight teeth for bond strength test, were divided into eight groups according to the different treatments (A: only treated with the adhesive Adper Easy One, B: diamond bur polishing followed by the above adhesive, C-H: Er,Cr:YSGG laser irradiating at 1 W, 2 W, 3 W, 4 W, 5 W, 6 W output power, respectively, followed by the above adhesive), and each group was subsequently divided into two subgroups according to whether aging is performed (immediately tested and after thermocycling). Micro-shear bond strength test was used to evaluate the bond strength.
  
  
  RESULTS
  The 4W laser group showed the highest roughness value (30.84±1.93μm), which was statistically higher than the control group and the diamond bur groups (p<0.05). The mean percentages ((27.8±1.8)%, (28.0±2.2)%, (30.0±1.9)%) of open tubules area in the 4W, 5W, 6W group were higher than other groups (p<0.05). The 4W laser group showed the highest micro-shear bond strength not only in immediately tested (17.60±2.55 PMa) but after thermocycling (14.35±2.08MPa).
  
  
  CONCLUSIONS
  The Er,Cr:YSGG laser at 4W power can effectively improve the bonding property between non-carious sclerotic dentin and resin composites by increasing the roughness and mean percentage area of open tubules.
authors.affiliation: State Key Laboratory of Military Stomatology, Department of VIP Dental Care, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Preventive Dentistry, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Jinghao
authors.initials: J
authors.lastname: Ban
authors.affiliation: State Key Laboratory of Military Stomatology, Department of VIP Dental Care, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Xinjia
authors.initials: X
authors.lastname: Sha
authors.affiliation: Department of Stomatology, No.117 Hospital of PLA, Hangzhou, P.R. China.
authors.forename: Weiguo
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.|Shaanxi Key Laboratory of Stomatology, Xi'an, P.R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Jiao
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Wanshan
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Stomatology, Lanzhou General Hospital Lanzhou Command of PLA, Lanzhou, China.
authors.forename: Yanwei
authors.initials: Y
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.|Shaanxi Key Laboratory of Stomatology, Xi'an, P.R. China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.|Shaanxi Key Laboratory of Stomatology, Xi'an, P.R. China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, P.R. China.|Shaanxi Key Laboratory of Stomatology, Xi'an, P.R. China.
authors.forename: Jihua
authors.initials: J
authors.lastname: Chen
mesh_terms: D000818:Animals; D002417:Cattle; D003804:Dentin / Q000473:pathology* / Q000528:radiation effects; D053844:Lasers, Solid-State; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D012117:Resins, Synthetic; D012598:Sclerosis; D033081:Shear Strength; D013499:Surface Properties
chemical_list: D012117:Resins, Synthetic