Induced periimplantitis in a novel mini‐pig model‐ description and defect characterization

Abstract

Background The use of animals to evaluate clinical response and progression of several oral diseases has been used toward time. For periodontology and implant dentistry several dog models were described and extensively used during the last 70 years. More recently, due to a series of movements against the use of canine models has restrained precluded the use of dogs for biological evaluation in several countries. Thus the use of other animals such as mini-pigs has gained space on oral research. Aim/Hypothesis This study has the original intention of compare treatments for induced Periimplantitis. The collected data until this time point will be presented in order to characterize the disease induction in this new model. Materials and Methods Eight Mini-pigs from the same breeder (Minipig br1) received eight implants each. After 8 weeks, healing abutments were installed and are 2 more weeks, silk ligatures were placed and left to accumulate plaque in association with a was wetted to a slurry food during 8 more weeks for plaque accumulation disease induction+ after 8 weeks radiographic data when collected to evaluate bone loss and the ligature were maintained for additional 8 weeks, when a bone loss of at least 30% of the implant could be detected, the ligatures were removed + after 3 more weeks, the clinical signs of disease were evaluated and periimplant bone loss was measured by x-rays. The treatment of the induced lesions was performed, and the defects characterization was recorded trans-surgically. This study will show the characteristics of the defects and data from two animals that died before the end of the study. Results The ligatures successfully induced progressive bone loss and ligature removal reduced the signs of acute inflammation. The progression rate was slower than the obtained in a previous study of our group in dog model. There were circumferential defects as well as horizontal bone loss, buccal and lingual bone dehiscence were not frequent and occurred mainly in the presence of horizontal bone loss. Vertical defects appeared mainly at interproximal areas (2.84 mm SD 2.35 mm). The defects configuration was similar to humans but, as this model does not control the pattern of bone loss, different defects can be found in the same experimental unit. Conclusion and Clinical Implications The use of mini-pig as a model to study periimplantitis produced defects comparable to human periimplantitis lesions with acute and chronic characteristics and might be a feasible alternative to the already described dog model.