Human studies

Studies on the morphogenesis and morphology of the mucosa at implants in humans used block biopsies obtained from mini‐implants or from soft tissue dissection techniques from conventional or specially designed abutments. Tomasi et al. presented a de novo biopsy technique and reported on the morphogenesis of the peri‐implant mucosa at single implant sites in human volunteers. Soft tissue biopsies were sampled after 2, 4, 8, and 12 weeks of healing following abutment connection. They reported that after 2 weeks large areas of the severed connective tissue were infiltrated with inflammatory cells, while after 4 weeks the infiltrated areas were smaller and a short barrier epithelium had formed in the interface zone. Sections representing later phases of observation exhibited continued healing of the connective tissue wound and the formation of a well‐defined barrier and sulcular epithelium in the marginal portion of the soft tissue samples. The height of the peri‐implant mucosa, measured along the profile of the soft tissue, increased during the healing phase from 2.7 mm at 2 weeks to between 3.0 and 3.5 mm after 4, 8, and 12 weeks. In the corresponding intervals the length of the epithelium varied between 2.2 and 2.0 mm, while the zone of connective tissue adhesion varied between 1.7 and 1.1 mm.

In summary, results from the available studies in man and from animal experiments are consistent and document that the peri‐implant mucosa is about 3 to 4 mm high with an epithelium that is about 2 mm long.