title: Biological complications and peri-implant clinical and radiographic changes at immediately placed dental implants. A prospective 5-year cohort study.
abstract: OBJECTIVE
  To evaluate clinically and radiographically immediate implants 5 years after insertion and to compare them with delayed-placed implants in the same subjects.
  
  
  METHODS
  Twenty-two consecutive patients that needed at least two implants for replacing hopeless teeth, one immediately upon extraction and the other in a delayed fashion (at least 4 months post-extraction) were selected in this prospective cohort study. Post-extraction immediate implants (II) and delayed implants (DI) groups were defined. One and 5 years after implant loading, clinical and radiographical outcome variables were recorded and analysed both at site and at implant level. Intra-group and inter-group comparisons were performed.
  
  
  RESULTS
  The intergroup comparison did not show significant differences for plaque index, bleeding on probing and suppuration. These parameters worsen in both groups along the study. This trend was stronger for the plaque index in the group II, which increased from 15.6% at 1 year to 25.9% at 5 years (P < 0.04). One year after loading, the sites with probing depth ≥5 mm were higher for the group II compared to DI (2.5% vs. 0%; P = 0.049). At the end of the study, no significant statistical differences were found. Radiographically, bone crestal changes did not yield significant differences. During the follow-up period, 25% of the implants (26.4% in group II and 23.5% in DI) showed biological complications: mucositis (20%) and/or periimplantitis (5.8%). No differences between groups were found.
  
  
  CONCLUSIONS
  Within the same patients, the implants placed with the immediate protocol demonstrated a higher tendency to crestal bone loss and to peri-implantitis, although these differences were not statistically significant.
authors.affiliation: Graduate Periodontology, Faculty of Odontology-University Complutense of Madrid, Madrid, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rodrigo
authors.forename: Conchita
authors.initials: C
authors.lastname: Martin
authors.forename: Mariano
authors.initials: M
authors.lastname: Sanz
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D005260:Female; D006801:Humans; D057893:Immediate Dental Implant Loading; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000453:epidemiology*; D011446:Prospective Studies; D011859:Radiography; D015203:Reproducibility of Results; D012307:Risk Factors; D018709:Statistics, Nonparametric; D016896:Treatment Outcome