Regarding the stability of peri-implant hard and soft tissue, biological or anatomical factors are not the only elements that could be proven to have an impact. Technical factors such as the implant-abutment connection are also known to be key factors for long-term stable hard- and soft-tissue health [11]. Regarding the implant-abutment connection, which seems to be the key issue, located on the interface between the implant, the peri-implant bone, the peri-implant soft tissue, and the oral cavity, different studies have shown that a Morse-tapered conical connection reduces the micro-movement and therefore the micro-motions, which results in a pump effect of sulcus fluid and microorganisms in the fragile peri-implant soft tissue [10, 12]. The conical connection leads to a kind of “cold welding” type of connection that seems to prevent bone loss compared to external implant-abutment connections [10, 12].

A further factor, which has been detected to improve peri-implant hard- and soft-tissue health and is related to a conical implant-abutment connection, is a “platform switching” design. By switching the platform between the implant and the abutment from the outside surface of the implant to the inside region and therefore in larger distance to the peri-implant hard and soft tissue, the colonization of microorganisms seems to be reduced. Furthermore, the conical connection in combination with a platform switching design decreases stress transferred onto the peri-implant bone. As a result, peri-implant bone loss is prevented and the peri-implant soft- and hard-tissue health can be preserved [11, 13].

The aim of the present retrospective investigation was to assess clinically and radiologically peri-implant tissue conditions and document peri-implant tissue stability in C-Tech implants when placed simultaneously with a GBR augmentation procedure after at least 3 years of loading.