title: Baseline radiographic defect angle of the intrabony defect as a prognostic indicator in regenerative periodontal surgery with enamel matrix derivative.
abstract: BACKGROUND
  The baseline radiographic defect angle has previously been correlated with the clinical outcomes of intrabony defects treated with access flap or guided tissue regeneration. The aim of this study was to investigate whether an association exists between baseline radiographic defect angle and treatment outcome when enamel matrix derivative (EMD) is used in periodontal regenerative surgery.
  
  
  METHODS
  Baseline radiographs were collected from the test group of a previously published clinical trial using a population of 166 patients treated for chronic periodontitis. All intrabony defects were > or =3 mm for inclusion in the original study. Either modified or simplified papilla preservation technique was used to access the defect. The roots were conditioned with an EDTA gel and the primary outcome measure was clinical attachment level (CAL) change, 1 year after surgery.
  
  
  RESULTS
  Sixty-seven radiographs were measurable. The probability of obtaining CAL gain >3 mm was 2.46 times higher (95% confidence interval: 1.017-5.970) when the radiographic defect angle was < or =22 degrees than when it was > or =36 degrees.
  
  
  CONCLUSIONS
  This study showed that there was a significant association between baseline radiographic defect angle and CAL gain at 1 year. The observed increased odds ratio of obtaining CAL gain of > or =4 mm after regenerative surgery with EMD is used in narrow (< or =22 degrees ) intrabony defects, suggests that the baseline radiographic defect angle might be used as a prognostic indicator of treatment outcome.
authors.affiliation: Department of Periodontology, Eastman Dental Institute and Hospital, University College London, UK.
authors.forename: Effie
authors.initials: E
authors.lastname: Tsitoura
authors.forename: Richard
authors.initials: R
authors.lastname: Tucker
authors.forename: Jean
authors.initials: J
authors.lastname: Suvan
authors.forename: Lars
authors.initials: L
authors.lastname: Laurell
authors.forename: Pierpaolo
authors.initials: P
authors.lastname: Cortellini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Tonetti
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000601:surgery; D001861:Bone Regeneration / Q000187:drug effects; D003746:Dental Enamel Proteins / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D011859:Radiography; D012189:Retrospective Studies
chemical_list: D003746:Dental Enamel Proteins; C109069:enamel matrix proteins