title: Bonding to ground versus unground enamel in fluorosed teeth.
abstract: OBJECTIVE
  To determine the effect of grinding on the bonding effectiveness of a self-etch and an etch-and-rinse adhesive to fluorosed enamel.
  
  
  METHODS
  The teeth were classified using the Thylstrup and Fejerskov index (TFI). Fluorosed teeth (TFI=5) obtained from Isparta (Turkey) and control teeth (TFI=0) obtained from Leuven (Belgium) were used. Using a depth-marking diamond bur, 0.3mm of enamel was removed from mid-buccal and mid-palatal/lingual surfaces of the teeth, whereas the area adjacent to the ground area was left unprepared. A two-step self-etch (Clearfil Protect Bond, Kuraray) and a three-step etch-and-rinse adhesive (Optibond FL, Kerr) were used to bond the resin composite to the ground and unground enamel. Rectangular micro-specimens were prepared using the slow-speed diamond saw and tested in tensile to determine the micro-tensile bond strength (microTBS).
  
  
  RESULTS
  The microTBS to unground fluorosed enamel was significantly lower than to ground fluorosed enamel for Clearfil Protect Bond (15.8+/-15.2 and 45.0+/-12.4MPa, p<0.0001) and for Optibond FL (35.5+/-21.4 and 50.5+/-12.3MPa, p<0.05), respectively. In control teeth, Clearfil Protect Bond bonded better to ground enamel (p<0.01), whereas OptiBond FL exhibited a similar bonding effectiveness to ground and unground enamel (p=0.0634).
  
  
  CONCLUSIONS
  Preparation of enamel improved the resin-enamel bond strength in fluorosed teeth. The bonding effectiveness to unground enamel was lower in fluorosed teeth than in control teeth for the self-etch adhesive tested.
authors.affiliation: Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-facial Surgery, Catholic University of Leuven, Kapucijnenvoer 7, B-3000 Leuven, Belgium.
authors.forename: R Banu
authors.initials: RB
authors.lastname: Ermis
authors.forename: Jan
authors.initials: J
authors.lastname: De Munck
authors.forename: Marcio Vivan
authors.initials: MV
authors.lastname: Cardoso
authors.forename: Eduardo
authors.initials: E
authors.lastname: Coutinho
authors.forename: Kirsten L
authors.initials: KL
authors.lastname: Van Landuyt
authors.forename: André
authors.initials: A
authors.lastname: Poitevin
authors.forename: Paul
authors.initials: P
authors.lastname: Lambrechts
authors.forename: Bart
authors.initials: B
authors.lastname: Van Meerbeek
mesh_terms: D000269:Adhesives / Q000737:chemistry; D000704:Analysis of Variance; D001840:Dental Bonding / Q000379:methods*; D003743:Dental Enamel / Q000002:abnormalities / Q000737:chemistry*; D045662:Dental Etching / Q000379:methods; D009050:Fluorosis, Dental; D006801:Humans; D013718:Tensile Strength
chemical_list: D000269:Adhesives