title: Bracket base remnants after orthodontic debonding.
abstract: OBJECTIVE
  To evaluate whether the debonding procedure leads to restitutio ad integrum of the enamel surface by investigating the presence of enamel within the bracket base remnants after debonding.
  
  
  METHODS
  Sixty patients who completed orthodontic treatment with fixed appliances were included. A total of 1068 brackets were microphotographed; the brackets presenting some remnants on the base (n = 818) were selected and analyzed with ImageJ software to measure the remnant area. From this population a statistically significant sample (n = 100) was observed under a scanning electron microscope to check for the presence of enamel within the remnants. Energy dispersive x-ray spectrometry was also performed to obtain quantitative data.
  
  
  RESULTS
  Statistically significant differences in the remnant percentage between arches were observed for incisor and canine brackets (P < .0001 and P = .022, respectively). From a morphologic analysis of the scanning electron micrographs the bracket bases were categorized in 3 groups: group A, bases presenting a thin enamel coat (83%); group B, bases showing sizable enamel fragments (7%); group C, bases with no morphologic evidence of enamel presence (10%). Calcium presence was noted on all evaluated brackets under energy dispersive x-ray spectrometry. No significant difference was observed in the Ca/Si ratio between group A (16.21%) and group B (18.77%), whereas the Ca/Si ratio in group C (5.40%) was significantly lower than that of the other groups (P < .323 and P = .0001, respectively).
  
  
  CONCLUSIONS
  The objective of an atraumatic debonding is not achieved yet; in some cases the damage could be clinically relevant.
authors.affiliation: Department of Orthodontics, University of Bologna, Bologna, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Zanarini
authors.forename: Antonio
authors.initials: A
authors.lastname: Gracco
authors.forename: Monica
authors.initials: M
authors.lastname: Lattuca
authors.forename: Silvia
authors.initials: S
authors.lastname: Marchionni
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Gatto
authors.forename: Giulio Alessandri
authors.initials: GA
authors.lastname: Bonetti
mesh_terms: D000293:Adolescent; D002648:Child; D003738:Dental Cements / Q000009:adverse effects*; D017005:Dental Debonding / Q000009:adverse effects*; D003743:Dental Enamel / Q000293:injuries*; D005260:Female; D006801:Humans; D008297:Male; D008855:Microscopy, Electron, Scanning; D016910:Orthodontic Brackets / Q000009:adverse effects*; D013052:Spectrometry, X-Ray Emission
chemical_list: D003738:Dental Cements