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CASE STUDY 8 IMPLANTOLOGICAL REHABILITATION OF A PRONOUNCED HARD AND SOFT TISSUE DEFECT IN THE ESTHETIC ZONE Dr. Jörg-Martin Ruppin, Penzberg, Germany, MDT Stefan Picha, Fürth, Germany Abstract Ever since the pioneering days of dental implantology, the definition of treatment success has further developed from purely achieving reliable osseointegration. Today, successful implantological rehabi- litation is unimaginable without esthetics, phonetics and function. Quite rightly, the patient's expectations have risen significantly over recent years. This emphasizes the importance of a strict “backward planning protocol” – the definition of an implant position selected according to prosthetic and esthetic aspects. Without correct surgical implant positioning, prosthetic success is often impossible to achieve. This underlines the importance of dependable augmentation techniques in order to be in a position to also surgically implement a prosthetically defined implant position. For many years now, autologous bone has been the unrivalled “gold standard” augmentation material. With regard to safety, long-term stability and the biological quality of an implant site, it is superior to all other augmentation techniques. It also offers the best long- term prognosis and the shortest healing time for the patient. To achieve prosthetic success, alongside correct hard tissue management, the relevant soft tissue management is just as important in the esthetic zone. Starting with the creation of sufficient soft tissue thickness, continuing with or without long-term temporaries, through to the selection of suitable abutment shapes and materials – many individual factors play a role, which only in correct interaction ensure long-term stable esthetic success. Introduction Dental implantology has continuously developed over the past twenty years. Thanks to advanced implant surfaces and surgical techniques, success rates of 95 – 99% are standard today [15, 18]. With reliable osseointegration presumed to be the “conditio sine qua non”, alongside functionality and long-term stability, the special focus is shifted to esthetics. Prosthetically oriented preoperative planning is decisive here. The catchword for this preoperative planning is backward planning. From the dental lab perspective, it is a matter of reconstructing the original positioning of the lost teeth on the basis of a wax-up or a logopedic set-up and to communicate this to the practitioner for precise planning of the implant position. With an eye on the prosthetically defined goal, the surgeon's task is to realize the planned implant position. Inflammatory processes prior to extraction of teeth not considered worth preserving can compromise the prospective implant site just the same as bone resorption due to inactivity atrophy with edentulism. Here the most common preoperative procedure is transversal widening of the alveolar ridge. Several techniques are described for this in the literature. The technique of bone spreading, also known as bone splitting, whereby the alveolar ridge is expanded buccally, is especially suitable for the upper jaw on account of the spongy bone structure [12]. However, with this method there is the inherent risk of uncontrolled postoperative re- sorption of the expanded bone of up to 40% and therefore certainly has to be viewed critically [8]. Lateral deposition techniques are superior in this regard. These may be performed as Guided Bone Regeneration (GBR) with membranes or titanium mesh. These techniques are best suited for small peri-implant bone defects and are described both with autologous bone, as well as bone bone replacement materials [2, 3, 18]. The augmentation material must always be covered with a barrier towards the soft tissue. Either non-resorbable barriers are used, such as GoreTex membranes or titanium mesh, or resorbable membranes, e.g. made of collagen of animal origin. Non-resorbable materials display sufficient resorption protection, but besides morbidity arising from the necessary surgical harvesting in a second procedure, there is also a considerable risk of wound dehiscence that can lead to infections and loss of the augmentation material [10]. Resorbable membranes reduce this risk, but it is yet to be clarified whether they offer sufficient resorption protection over time [5]. The use of autologous, corticocancellous bone grafts represents the safest method with the fewest complications. Bone grafts of this kind can be obtained intraorally or extraorally. Extraction in the region of the mandibular angle or the external iliac crest is most common. Given the correct surgical technique, the mandibular angle offers good bone availability, combined with only low risks and morbidity [11]. The sometimes pronounced cortical structure of the bone has to be viewed as a disadvantage, however. While intraoral harvesting is the gold standard for augmentation [11], if a very large amount of augmentation material is necessary, the iliac crest may also be used. The very good bone quality, vitality and availability is seen as an advantage. The increased extraction morbidity for the patient and the low resorption stability of the graft are