title: Crestal bone level changes around immediately placed implants: a systematic review and meta-analyses with at least 12 months' follow-up after functional loading.
abstract: BACKGROUND
  Immediate implant placement (IIP) is a successful treatment and has the advantages of reducing time and increasing patient satisfaction. However, achieving predictable esthetic results with IIP presents a challenge because of naturally occurring bone loss postextraction. Therefore, the focused question of this systematic review is: What is the effect of IIP on crestal bone level (CBL) changes after at least 12 months of functional loading?
  
  
  METHODS
  Extensive literature review of the Cochrane and MEDLINE electronic databases and a manual search up to November 2012 identified eligible studies. Two reviewers independently assessed the study data and methodologic quality using data extraction and assessment forms.
  
  
  RESULTS
  Electronic and manual searches identified 648 relevant publications. A total of 57 articles satisfied the inclusion criteria. Sixteen studies had test and control groups; therefore, meta-analyses could be performed. The results demonstrated better CBL preservation around IIP compared with implant placement in healed/native bone at 12 months [CBL difference of -0.242 (95% confidence interval [CI], -0.403 to -0.080; P = 0.003)]. Similarly, platform switching around IIP showed better results compared with non-platform switching (CBL difference of -0.770 [95% CI, -1.153 to -0.387; P <0.001]). There was no difference in mean CBL changes with regard to one-stage or two-stage IIP protocol (-0.017 [95% CI, -0.249 to 0.216; P = 0.85]) or the use of immediate or delayed immediate implant loading (0.002 [95% CI, -0.269 to 0.272; P = 0.99]).
  
  
  CONCLUSIONS
  Meta-analyses showed less CBL loss around IIP compared with implant placement in healed bone. Platform-switched implants showed greater crestal bone preservation than non-platform-switched implants. There was no significant difference in CBL with one- versus two-stage placement or use of immediate versus delayed IIP loading. Although there were statistically significant differences favoring IIP, the small differences may not be clinically relevant. Although IIP showed favorable outcomes for CBL changes, these results should be interpreted with caution because of high heterogeneity among studies.
authors.affiliation: Department of Periodontology and Dental Hygiene, University of Detroit Mercy School of Dentistry, Detroit, MI.
authors.forename: Bassam M
authors.initials: BM
authors.lastname: Kinaia
authors.forename: Maanas
authors.initials: M
authors.lastname: Shah
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Neely
authors.forename: Harold E
authors.initials: HE
authors.lastname: Goodis
mesh_terms: D016301:Alveolar Bone Loss / Q000209:etiology; D000539:Alveolar Process / Q000033:anatomy & histology*; D059605:Dental Implant-Abutment Design; D003758:Dental Implantation, Endosseous / Q000379:methods; D015921:Dental Implants; D005500:Follow-Up Studies; D006801:Humans; D057893:Immediate Dental Implant Loading / Q000379:methods
chemical_list: D015921:Dental Implants
keywords: Alveolar bone loss; dental implants; meta-analysis; review; systematic; tooth extraction