title: Early and late studies of EMD use in periodontal intrabony defects.
abstract: OBJECTIVE
  The clinical efficacy of EMDs for the treatment of periodontal infrabony defects has been reported. However, recent publications have questioned the validity of results from early findings. Hence, the purpose of this study was to compare the results obtained from early and late studies when EMD was used as an adjunct in treating human intrabony defects during flap surgery. The aim of this meta-analysis was to evaluate the validity of results published from early studies compared with those published from later studies.
  
  
  METHODS
  PubMed and MEDLINE searches were performed. The evaluation period was 1997-2010 and it was divided into two groups of equal periods of time: early studies (1997-2003) and late studies (2004-2010). The clinical parameters assessed were clinical attachment level (CAL), probing pocket depth and bone gain (BG; measured as a percentage or in mm).
  
  
  RESULTS
  No statistically significant difference was found between the results obtained from early studies (1997-2003) and late studies (2004-2010) with regards to CAL gain, probing pocket depth reduction and BG. Nonetheless, both study periods showed a benefit for using EMD to treat periodontal infrabony defects when compared with the groups without EMD during open flap surgery.
  
  
  CONCLUSIONS
  The results obtained from this study failed to show any potential differences between the results published from early studies and late studies with regards to the clinical effectiveness of EMD in treating periodontal infrabony defects.
authors.affiliation: Graduate Periodontics, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA.
authors.forename: V T
authors.initials: VT
authors.lastname: Mueller
authors.forename: K
authors.initials: K
authors.lastname: Welch
authors.forename: D C
authors.initials: DC
authors.lastname: Bratu
authors.forename: H-L
authors.initials: HL
authors.lastname: Wang
mesh_terms: D016301:Alveolar Bone Loss / Q000473:pathology / Q000601:surgery*; D000539:Alveolar Process / Q000473:pathology; D003746:Dental Enamel Proteins / Q000627:therapeutic use*; D006801:Humans; D010012:Osteogenesis / Q000502:physiology; D017622:Periodontal Attachment Loss / Q000473:pathology / Q000601:surgery; D010514:Periodontal Pocket / Q000473:pathology / Q000601:surgery; D015203:Reproducibility of Results; D013524:Surgical Flaps; D016896:Treatment Outcome
chemical_list: D003746:Dental Enamel Proteins; C109069:enamel matrix proteins