Prof. Dr Dr Anton Sculean (Bern), attending remotely, talked about options and limitations when covering implant recessions. Citing the differences in biological anchorage between natural teeth and implants, he explained that implants are in direct contact with the bone and that the soft tissue surrounding them is less vascularised than that around teeth, which has to be taken account in soft-tissue surgery. According to Sculean, there are two components to the mucosal seal –connective-tissue integration and the epithelial layer. The former in particular is of major importance if infections arise in this area. Aetiological factors of any soft-tissue recession at implants primarily include incorrect implant placement – too far buccally or labially or, conversely, too far palatally or lingually. Other aetiological factors include the absence of a bony envelope and excessive implant diameters relative to the existing bone supply; an excessive number of implants; insuffi cient distance between implants, causing the loss of the interimplant papilla; insuffi cient distance between implants and natural teeth; insuffi cient mucosal thickness or insuffi cient attached keratinized mucosa; and, of course, peri-implant mucositis and peri-implantitis. The only appropriate comment if implants are placed too far outside the bony envelope, said Sculean, would be “Mission Impossible” – here the only possible action would be to remove the implant or implants altogether.

What kind of tissue recession, then, remains amenable to coverage around implants? Sculean believes that successful treatment is possible if the dehiscence is no deeper than 2–3 mm, 4 mm at the very most, or if the implant is reasonably fi rmly positioned within the bony envelope. He then proceeded to present some of his cases using the modifi ed (MCAT) and lateral (LCT) tunnelling techniques. The idea, he said, is not to separate the papillae but to expose this area as part of a mucoperiosteal tunnelling procedure, so that new tissue – such as a connective-tissue graft – can be introduced to reinforce the tissue. The important thing here is tension-free preparation. – For Sculean, tunnelling techniques are a good option for addressing small mucosal defects, as long as the implant is not too far outside the bony envelope, as pointed out previously.