title: Concurrent evaluation of composite internal adaptation and bond strength in a class-I cavity.
abstract: OBJECTIVE
  This study investigated class-I cavity floor adaptation by swept-source optical coherence tomography (OCT) in combination with microtensile bond strength (MTBS) using different filling methods.
  
  
  METHODS
  Two adhesive systems; Tokuyama Bond Force and Tri-S Bond Plus were used in conjunction with a universal composite (Estelite Sigma Quick) placed either incrementally (oblique) or in bulk with or without a flowable composite lining (Palfique Estelite LV). Ten serial B-scan images were obtained throughout each cavity by OCT (center wavelength: 1319nm). In order to evaluate adaptation defined as the cavity floor percentage showing no gap, a significant increase in the signal intensity was considered as gap at the bonded interface of the cavity floor. The same specimens were then cut into beams to measure MTBS at the cavity floor.
  
  
  RESULTS
  Two-way ANOVA demonstrated that the interaction of adhesive systems and filling techniques was significantly affecting both adaptation and MTBS (p<0.05). There was a significant correlation between MTBS and adaptation at cavity floor (p<0.05). Cavity floor adaptation and MTBS were improved when incremental filling technique was applied, while the outcome of lining technique was variable.
  
  
  CONCLUSIONS
  Quantitative assessment by OCT can non-destructively provide information on the performance and effectiveness of dental composites and restoration techniques. There was a moderate correlation between floor adaptation and bond strength in class-I cavities. Incremental application of composite restoration showed the best performance in terms of bond strength and internal adaptation.
  
  
  CONCLUSIONS
  Incremental application of composite restoration was the most advantageous placement technique in terms of bond strength and internal adaptation. The lack of placement pressure with flowable composites may affect their adaptation to all-in-one adhesives; therefore, the outcome of cavity lining by flowable composite was variable.
authors.affiliation: Cariology and Operative Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia; Cariology and Operative Dentistry, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Turki A
authors.initials: TA
authors.lastname: Bakhsh
authors.forename: Alireza
authors.initials: A
authors.lastname: Sadr
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shimada
authors.forename: Mona M
authors.initials: MM
authors.lastname: Mandurah
authors.forename: Ilnaz
authors.initials: I
authors.lastname: Hariri
authors.forename: Ehab Z
authors.initials: EZ
authors.lastname: Alsayed
authors.forename: Junji
authors.initials: J
authors.lastname: Tagami
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Sumi
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003736:Dental Cavity Lining / Q000379:methods; D003737:Dental Cavity Preparation / Q000145:classification*; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003793:Dental Restoration, Permanent / Q000379:methods; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000033:anatomy & histology; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D018613:Microscopy, Confocal; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D041623:Tomography, Optical Coherence
chemical_list: C515604:Clearfil Tri-S Bond; D003188:Composite Resins; D003764:Dental Materials; C507124:Estelite sigma; D008689:Methacrylates; D011109:Polymethacrylic Acids; D019279:Resin Cements; C086113:palfique estelite; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; C005044:hydroxyethyl methacrylate