title: Drying and rewetting anterior crown fragments prior to bonding.
abstract: Fractured anterior teeth can be restored by adhesive bonding of the fragment to the remaining tooth structure. This in vitro study describes the effect on fracture strength of fragments dried and rewetted for various periods of time prior to bonding. Seventy central incisors from sheep were fractured. The resulting incisal crown fragments were then stored in air at room temperature at ambient humidity (70 +/- 16%) for 5 s, 30 min, 1 h, 3 h, 6 h, 12 h, or 24 h. The apical parts of the fractured teeth were stored in water. After storage in air each fragment was then bonded to the matching apical tooth structure with a bonding agent and a low-viscosity composite resin. After water storage for 2 days, mean fracture strength was measured. Another group of teeth comprising 40 sheep central incisors was fractured and the fragments were stored in air at room temperature for 24 h as above. The fragments were then immersed in water for 10 min, 1 h, 1 day, or 7 days, prior to bonding and measurement as described above. Statistical analysis revealed that the fracture strength of the fragment-bonded teeth was unaffected by air storage of the fragment for up to 1 h prior to bonding, after which additional drying resulted in decreased fracture strength. Fragments dried for 24 h in air and rewetted by immersion in water for at least 1 day were fragment-bonded without loss of fracture strength.
authors.affiliation: Department of Pediatric Dentistry, School of Dentistry, University of Copenhagen, Denmark. ban@odont.ku.dk
authors.forename: B
authors.initials: B
authors.lastname: Farik
authors.forename: E C
authors.initials: EC
authors.lastname: Munksgaard
authors.forename: J O
authors.initials: JO
authors.lastname: Andreasen
authors.forename: S
authors.initials: S
authors.lastname: Kreiborg
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D017609:Barium Compounds / Q000627:therapeutic use; D017438:Bisphenol A-Glycidyl Methacrylate / Q000627:therapeutic use; D001840:Dental Bonding / Q000379:methods*; D017220:Dentin-Bonding Agents / Q000627:therapeutic use*; D003890:Desiccation; D007180:Incisor / Q000293:injuries; D008689:Methacrylates / Q000627:therapeutic use; D019279:Resin Cements / Q000627:therapeutic use; D012756:Sheep; D012822:Silicon Dioxide / Q000627:therapeutic use; D018709:Statistics, Nonparametric; D019228:Tooth Crown / Q000293:injuries*; D014082:Tooth Fractures / Q000628:therapy*; D014867:Water; D017155:Wettability
chemical_list: C121035:Aeliteflo; D017609:Barium Compounds; C103506:Bis-GMA, BPDM, HEMA dental-bonding resin; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D019279:Resin Cements; D014867:Water; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide