Supracrestal bone growth around partially inserted titanium implants in dogs. A pilot study

8 titanium implants (Nobel Biocare, Göteborg, Sweden) were inserted into edentulous lower premolar areas of 4 dogs so that 6 threads of the implant protruded from the bone crest. Newly-developed perforated dome-shaped titanium space maintainers were fixed to the implant with cover screws. Autogenous bone fragments were placed under the space maintainers. On one side of the arch, the space maintainer was covered with a non resorbable cell occluding barrier. The implant/space maintainers were submerged under coronally positioned flaps. Following a 3-month healing period, there was a mean gain of new bone amounting to 2.5 mm for all specimens. A greater height of bone was found for those sites in which an ePTFE membrane was used; 3.1 mm vs. 1.9 mm (p < 0.05). This study demonstrated the potential of coronal bone growth of the alveolar bone in a protected space around crew implants with exposed treads when placed in the dog.