Peri-implant tissues morphometry at SLActive surfaces. An experimental study in the dog

ObjectiveThe objective was to study tissue components around implants with highly hydrophilic surfaces during early healing.Materials and methodsIn 12 Labrador dogs, the second and third mandibular premolars were extracted bilaterally. After 3months of healing, full-thickness flaps were elevated in the edentulous region of one side of the mandible. An implant was installed, and the flaps were sutured to allow a non-submerged healing. The timing of the implant installations in the other side of the mandible until sacrifices were performed in such a way to collect biopsies representing healing after 4, 7, 15, and 60days. An n=6 was achieved for each healing period. Paraffin sections were obtained for morphometric analyses.ResultsProvisional matrix with a percentage of 32.916.7% was found already after 4days. This percentage became 37.3 +/- 8.5%, 24.3 +/- 9.1%, and 1.6 +/- 1.7 after 7, 15, and 60days, respectively. New bone was found after 7days of healing, at a percentage of 26.2 +/- 3.2%. This proportion increased to 36.0 +/- 9.6% and 50.4 +/- 8.3% after 15 and 60days, respectively. Marrow spaces free from a blood clot, inflammatory cells, and provisional matrix represented a low proportion of the tissues after 4days (1.6 +/- 2.4%). This proportion increased over time to 9.2 +/- 6.4%, 20.3 +/- 12.9%, and 37.9 +/- 9.6%, respectively. The percentage of old bone was noted in a similar percentage (similar to 8%) up to 15days. The percentage decreased to similar to 5% at 60-day of observation.ConclusionThe tissue changes observed during the healing were similar to those from historic controls studying healing in a chamber adjacent to implants. Hence, the characteristics of the implant surfaces may not be reflected in the tissue composition adjacent to the implant but rather affect the adhesion of tissue onto the implant surfaces.