Osseintegration following treatment of peri-implantitis and replacement of implant components - An experimental study in the dog

Aim: The aim of the present experiment was to study if the quality of the titanium surface is a decisive factor for osseointegration and re-osseointegration. Material and Methods: 2 Labrador dogs were used. The mandibular Ist molars and all premolars were removed bilaterally. 3 months later, 1 standard fixture and 3, 2-part "test fixtures" were installed in each side of the mandible. The text fixtures consisted of 1 6-mm long apical and 1 4-mm long coronal part connected with an internal screw. After 4 months, abutment connection was performed. 5 months later, a period of experimental peri-implantitis was initiated during which about 50% of the supporting bone tissue was lost. The dogs were later subjected to a treatment that included (i) systemic administration of antibiotics and (ii) surgical debridement of all implant sites. The abutments and the coronal parts of the text fixtures were removed. All parts of the exposed portion of the standard fixtures, the connecting screw and the apical part of the test fixtures were meticulously cleaned by mechanical means. A pristine, coronal fixture part was via the connecting screw attached to the apical fixture part of each text fixture. All fixtures were submerged. 2 weeks later, a fluorochrome was injected intravenously. After 4 months, biopsies of the implant sites were dissected and prepared for ground sectioning and analysis. Results: It was demonstrated that re-osseointegration failed to occur to implant surfaces (standard) exposed to bacterial contamination, but did consistently occur at sites where a pristine implant component was placed in the bone defect following surgical debridement. Conclusion: The above findings seem to imply that the quality of the titanium surface is of decisive importance for both osseointegration and re-osseointegration.