title: Enamel loss following ceramic bracket debonding: A quantitative analysis in vitro.
abstract: OBJECTIVE
  To measure enamel surface changes after ceramic bracket debonding and after cleanup.
  
  
  METHODS
  Forty extracted teeth were scanned in three dimensions using an optical scanner (baseline). Two ceramic bracket systems were placed (19 metal-reinforced polycrystalline ceramic brackets; 21 monocrystalline ceramic brackets). Seven days later, brackets were debonded and teeth scanned (post-debond). Adhesive remnants and bracket fragments were recorded. Tooth surfaces were cleaned using a finishing carbide bur and scanned again (post-cleanup). Post-debond and post-cleanup scans were aligned with the baseline, and surface changes were quantified. Results were statistically compared using t-tests and Mann-Whitney tests (α  =  .05).
  
  
  RESULTS
  The depth of enamel loss (mean ± standard deviation) post-debond was 21 ± 8 µm and 33 µm and post-cleanup was 28 ± 14 µm and 18 ± 8 µm (P  =  .0191); the post-debond remnant thickness was 188 ± 113 µm and 120 ± 37 µm (P  =  .2381) and post-cleanup was 16 ± 5 µm and 15 µm for polycrystalline and monocrystalline ceramic brackets, respectively. The monocrystalline ceramic brackets predominantly left all adhesive on the tooth; the polycrystalline ceramic brackets were more likely to leave bracket fragments attached.
  
  
  CONCLUSIONS
  Both systems allowed successful removal of the brackets with minimal enamel loss. However, the polycrystalline ceramic brackets left more fragments on the tooth, which complicated cleanup efforts.
authors.affiliation: a  Senior Resident, Department of Orthodontics, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tenn.
authors.forename: Sam N
authors.initials: SN
authors.lastname: Suliman
authors.affiliation: b  Associate Professor and Department Chair, Department of Orthodontics, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tenn.
authors.forename: Terry M
authors.initials: TM
authors.lastname: Trojan
authors.affiliation: c  Associate Professor, Department of Restorative Dentistry, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tenn.
authors.forename: Daranee
authors.initials: D
authors.lastname: Tantbirojn
authors.affiliation: d  Professor and Director of Biomaterials Research, Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, Tenn.
authors.forename: Antheunis
authors.initials: A
authors.lastname: Versluis
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D002516:Ceramics / Q000737:chemistry*; D055117:Curing Lights, Dental / Q000145:classification; D017005:Dental Debonding / Q000295:instrumentation / Q000379:methods*; D003743:Dental Enamel / Q000473:pathology*; D003764:Dental Materials / Q000737:chemistry*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008422:Materials Testing; D061848:Optical Imaging / Q000379:methods; D016910:Orthodontic Brackets / Q000145:classification; D019279:Resin Cements / Q000737:chemistry; D013499:Surface Properties
chemical_list: D003764:Dental Materials; D019279:Resin Cements; C477790:Transbond XT
keywords: Ceramic bracket; Debonding; Dental finishing; Digital scan; Enamel loss