The prevalence of peri-implantitis has grown in the past few years and has become a major issue in implant dentistry. Long-term stable and healthy soft- and hard-tissue conditions should be achieved in combination with esthetically and functionally satisfying results. However, the rising number of placed implants in the past decades has come with an increase in the prevalence of peri-implantitis [1].

Peri-implantitis is defined as a pathological inflammation of the peri-implant soft and hard tissue leading to peri-implant bone loss. For pathogenesis, many different factors are discussed in the literature. Reviews have shown that oral hygiene, implant surgery factors such as implant position, soft- and hard-tissue amount and quality, prosthetic concepts and design, general medical history, and other factors have an impact on the establishment and progression of peri-implantitis [2].

Peri-implant soft tissue forms the first border of the peri-implant tissue to the oral cavity and therefore to the migration of microorganisms that can cause and accelerate peri-implant infections. Dental implants, unlike the natural teeth, do not possess a compact barrier against penetration properties of the oral cavity. Peri-implant soft tissue acts as a cuff-like barrier [3]. In contrast to the periodontal attachment, there is no connective tissue fiber insertion into the implant surface. The peri-implant soft tissue possesses a lower number of blood vessels [4, 5] and cells but a higher amount of collagen [3, 6]. As a consequence of these anatomical differences, the peri-implant soft tissue has a decreased defending mechanism against microorganisms that in a pathological amount causes peri-implant infections.

A major etiological factor for peri-implantitis is the position of the implant in the surrounding bone [2]. In addition to bone quality and vascularization, a sufficient amount of peri-implant bone is important for the long-term stability of the implant and a sufficient underlining to the peri-implant soft tissue [2]. However, in most patients, the local bone amount is reduced due to atrophy, inflammatory processes, or resectional defects. Therefore, in the past few years, different techniques have been described to enlarge the local bone amount in prospective implant sites [7]. Besides methods such as GBR or the sinus augmentation technique, different augmentation materials have been investigated and established in the daily clinical routine. Autologous bone in the context of hard tissue augmentations is still the gold standard due to its osteogenic capacity [8]. To avoid the disadvantages that come with autologous bone transfer, such as a second surgical site and an increase in postoperative pain, biomaterial research has focused on the development of bone substitute materials that serve as scaffolds for the ingrowth of bone and its progenitor cells from the surrounding tissue [9].