title: Platelet-rich plasma for periodontal regeneration in the treatment of intrabony defects: a meta-analysis on prospective clinical trials.
abstract: OBJECTIVE
  The aim of this systematic review and meta-analysis was to assess the influence of platelet-rich plasma (PRP) on the regeneration of periodontal intrabony defects by means of evaluating clinical and radiographic outcomes in prospective human clinical trials.
  
  
  BACKGROUND
  PRP is a high concentration of platelets suspended in a small volume of plasma and has been used for periodontal tissue regeneration. However, although it has been broadly studied, there is much controversy on its efficacy when used to treat infrabony periodontal defects.
  
  
  METHODS
  An electronic literature search was conducted by two reviewers (AR and AM) in several databases up to February 2014. The PICO question was: Does PRP have a higher or similar efficacy of regenerating periodontal intrabony defects compared with other conventional periodontal regeneration treatments (e.g., bone grafts, barrier membranes)? Articles were included in this systematic review if they were prospective clinical trials with 10 or more human patients, reporting the radiographic and/or clinical outcomes PRP for regeneration intrabony periodontal defects. Random effects meta-analyses of the selected studies were applied to avoid any bias being caused by methodologic differences among studies.
  
  
  RESULTS
  Twenty-two papers were obtained and reviewed. Of these, 21 articles fulfilled the inclusion criteria and subsequently were qualitatively analyzed. Eighteen of these could be meta-analyzed. Fourteen articles were included for evaluating of probing pocket depth (PPD). The weighted mean difference (WMD) was 0.55 mm, with a 95% CI=-0.09 to 1.20 mm (P=.09). For bone level (BL), 2 articles measured BL in millimeters, and the other two articles measured BL in percentage. The WMD was 0.76 mm (95% CI=0.21-1.31 mm; P=.007) and 47.41% (95% CI=32.48%-62.33%; P<.0001), respectively. For attachment level (AL) changes, 12 articles were included. The WMD was 0.58 mm, with a 95% CI=0.24 to 0.91 mm (P=.0008). Sixteen articles were included for evaluation of marginal gingival level (MGL). The WMD -0.10 mm, with a 95% CI=-0.19 to -0.01 (P=.03).
  
  
  CONCLUSIONS
  High heterogeneity among studies made it difficult to draw clear conclusions. Nonetheless, within the limitations of this review, PRP might offer some beneficial effects on clinical and radiographic outcomes for regeneration of periodontal intrabony defects.
authors.affiliation: Department of Oral and Maxillofacial Surgery, International University of Catalonia (UIC), Barcelona, Spain.
authors.forename: Àlvar
authors.initials: À
authors.lastname: Roselló-Camps
authors.affiliation: Graduate Student in Periodontics, Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, Michigan, USA. Electronic address: amonjec@umich.edu.
authors.forename: Alberto
authors.initials: A
authors.lastname: Monje
authors.affiliation: Graduate Student in Periodontics, Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, Michigan, USA.
authors.forename: Guo-Hao
authors.initials: GH
authors.lastname: Lin
authors.affiliation: Graduate Student in Periodontics, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, California, USA.
authors.forename: Vahid
authors.initials: V
authors.lastname: Khoshkam
authors.affiliation: Department of Oral and Maxillofacial Surgery, International University of Catalonia (UIC), Barcelona, Spain.
authors.forename: Mitchel
authors.initials: M
authors.lastname: Chávez-Gatty
authors.affiliation: Graduate Student in Periodontics, Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, Michigan, USA.
authors.forename: Hom-Lay
authors.initials: HL
authors.lastname: Wang
authors.affiliation: Department of Oral and Maxillofacial Surgery, International University of Catalonia (UIC), Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Gargallo-Albiol
authors.affiliation: Department of Oral and Maxillofacial Surgery, International University of Catalonia (UIC), Barcelona, Spain. Electronic address: Director@institutomaxilofacial.com.
authors.forename: Federico
authors.initials: F
authors.lastname: Hernandez-Alfaro
mesh_terms: D016301:Alveolar Bone Loss / Q000517:prevention & control*; D001861:Bone Regeneration; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D006801:Humans; D010510:Periodontal Diseases / Q000517:prevention & control*; D053657:Platelet-Rich Plasma; D011446:Prospective Studies