title: Evaluation of Different Implant Designs in a Ligature-Induced Peri-implantitis Model: A Canine Study.
abstract: OBJECTIVE
  Peri-implantitis is a challenging situation that leads to tissue destruction and eventual implant failure. The purpose of this study was to evaluate and compare, clinically and histologically, the influence of ligature-induced peri-implantitis on two implant designs in a canine extraction socket model.
  
  
  METHODS
  Sixty-four implants (4.1 × 13 mm) were placed bilaterally in eight dogs immediately after extraction of the mandibular premolars (P3, P4) and molars (M1, M2). Thirty-two conventional threaded implants (group A) and 32 tantalum-based porous implants (group B) were placed. After 12 weeks of normal healing, experimental peri-implantitis was induced in four dogs via the placement of ligatures subgingivally around the implant necks in the treatment group; the control group remained ligature-free. Two dogs in each group were euthanized after 12 or 26 weeks of plaque accumulation (control group dogs received regular cleanings). Clinical evaluations were conducted during the observation period and histologic sections were obtained for histologic and histomorphometric assessments.
  
  
  RESULTS
  All the implants exhibited clinical and histologic osseointegration. The treatment group showed significant loss of peri-implant tissue from the induced peri-implantitis. Pocket probing depths for the treatment groups were significantly greater than those of the control groups. Mean bone-to-implant-contact values were not statistically different for control vs treatment groups or for group A vs group B. In the treatment group, group B implants exhibited mean bone ingrowth of 28.4% to 36.3% and achieved more bone formation along the length of the implant than group A implants in the treatment group.
  
  
  CONCLUSIONS
  Implant design did not influence the tissue response or histomorphometric findings under induced peri-implantitis in the canine extraction socket.
authors.forename: Suneel
authors.initials: S
authors.lastname: Battula
authors.forename: Jin Whan
authors.initials: JW
authors.lastname: Lee
authors.forename: Hai Bo
authors.initials: HB
authors.lastname: Wen
authors.forename: Savvas
authors.initials: S
authors.lastname: Papanicolaou
authors.forename: Michael
authors.initials: M
authors.lastname: Collins
authors.forename: Georgios E
authors.initials: GE
authors.lastname: Romanos
mesh_terms: D000818:Animals; D001641:Bicuspid; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D003773:Dental Plaque; D017267:Dental Prosthesis Design; D004195:Disease Models, Animal; D004285:Dogs; D008026:Ligation; D016348:Osseointegration; D057873:Peri-Implantitis / Q000150:complications / Q000473:pathology*; D014081:Tooth Extraction; D020390:Tooth Socket / Q000473:pathology
chemical_list: D015921:Dental Implants