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Endodontic–periodontal lesions are characterized by the involvement of the pulp and periodontal disease in the same tooth. Despite successful root canal treatment, if the majority of bone support has been lost from periodontitis, the tooth may have a poor prognosis. In severe endodontic–periodontal lesions, the periodontal tissue regenerates poorly because of the significant loss of the periodontal ligament and cementum, poor tooth stability, and bone defect morphology unfavorable for bone regeneration. To overcome these difficult situations, in this case, osteotomy of the replantation bed and tooth replantation with horizontal rotation and deep placement were performed. To improve periodontal regeneration, fibroblast growth factor (FGF) 2 was applied to the artificially made periodontal defect. In addition, orthodontic extrusion of the deeply replaced tooth was performed for potential coronal migration of the periodontal tissue. This case presents a unique multidisciplinary  method of treating severe endodontic–periodontal lesions using intentional replantation combined with FGF 2 application and orthodontic extrusion. Keywords: Tooth replantation; periodontal regeneration; FGF2; orthodontic tooth extrusion; endodontic–periodontal lesions

Optimale implantatprothetische Versorgungen im Frontzahnbereich mit seinen hohen ästhetischen Anforderungen setzen ein ausreichendes Hart- und Weichgewebevolumen voraus, welches die Implantatrekonstruktion adäquat unterstützt und einrahmt und somit ein langfristig stabiles funktionelles und ästhetisches Resultat sicherstellt. Daher ist für die Behandlung ästhetisch relevanter Stellen ein gründliches Verständnis der räumlichen Beziehungen zwischen Hart- und Weichgewebe erforderlich. Für umfangreiche dreidimensionale Knochenaufbaumaßnahmen stehen mehrere gut untersuchte, zuverlässige Techniken zur Verfügung, unter denen besonders die gesteuerte Knochenregeneration hervorzuheben ist. Auch die Modifikation und Stellungskorrektur von Zähnen neben der künftigen Implantatstelle ist umfangreich diskutiert worden. So hat sich in jüngerer Zeit die verzögerte Extraktion nach vorangehender kieferorthopädischer Extrusion als zuverlässige Tech- nik erwiesen, um zusätzliches vertikales Hart- und Weichgewebe zu generieren. Ebenfalls diskutiert wurden verschiedene Behandlungssequenzen und zeitliche Abfolgen kombinierter Behandlungsansätze. Die Kombination kieferorthopädischer Maßnahmen mit einer Verzögerung der Extraktion kann, wie gezeigt wurde, die nötigen knöchernen Voraussetzungen an Implantatstellen schaffen, an denen herkömmliche Augmentationstechniken schlechter geeignet sind. Der Erfolg dieser Augmentationstechniken und Behandlungsmethoden setzt ein stabiles, gesundes Parodont voraus, da unkontrollierte Parodontalerkrankungen den Behandlungserfolg stark beeinträchtigen können. Der vorliegende Fallbericht möchte eine Abfolge von Techniken für das vertikale Hart- und Weichgewebemanagement zeigen, mit der sich ästhetisch und funktionell erfolgreiche Implantatversorgungen an Frontzahnstellen mit schweren parodontalen Defekten realisieren lassen. Keywords: Implantologie, mikroperforierte Titanmembran, nichtresorbierbare Titanwabenmembran, Teilextraktion, Parodontologie, Root-Submergence-Technik

Achieving optimal implant prosthodontic outcomes in the esthetically demanding anterior region requires sufficient hard and soft tissue volume to provide adequate support and coverage to ensure that the implant restorations are functional and yield predictable, long-lasting treatment results. A comprehensive biologic understanding of the 3D relationships between hard and soft tissue is crucial when treating esthetically demanding areas. Various techniques, notably guided bone regeneration, have been developed and are well documented as being reliable methods for larger 3D bone augmentation procedures. Additionally, dental modification and tooth repositioning in proximity to prospective implant placement sites has been extensively discussed. Recently, orthodontic extrusion with deferred extraction has emerged as a predictable treatment strategy for gaining additional vertical hard and soft tissue. Implementing treatment sequences and the timing of combined treatment methodologies have also been subjects of discussion. Combining orthodontic treatment with staged or delayed tooth extractions has been shown to be beneficial in providing the necessary osseous foundation for implant sites that may not be as amenable to more conventional augmentation techniques. These augmentation techniques and treatment methods require adequately stable and predictable periodontal health since uncontrolled periodontal disease poses a significant challenge and is detrimental to successful outcomes. The purpose of the present clinical report is to demonstrate the staging and sequencing of vertical hard and soft tissue management techniques for a severe anterior periodontal defect to achieve an esthetically functional implant treatment result. Keywords: implantology, nonresorbable titanium honeycomb membrane, partial extraction therapy, periodontology, root submergence

Periodontal regeneration therapy has developed tremendously since its inception, becoming a clinical tool to preserve the periodontally compromised natural dentition. More challenging esthetic defects can often benefit from the combination of bone and soft tissue regeneration, such as the application of connective tissue grafts (CTGs) and techniques that approach the bone defect without interdental papillae incisions. However, periodontal tissue regeneration vertical to the alveolar bone crest in cases of severe periodontitis, with loss of both soft and hard tissues, has not been predictably established. This case report describes a patient with severe periodontitis that was treated with in supra-alveolar periodontal tissue reconstruction. This innovative surgical technique requires both horizontal buccal incisions and several vertical palatal incisions, avoiding the interdental papillae on the periodontal defect. Then, a space is created by suspending and fixating the flap coronally, and CTG and regenerative materials (such as recombinant human fibroblast growth factor-2) and bone graft material are applied. This technique has the potential to gain clinical attachment, achieve supra-/intraperiodontal regeneration, and enhance esthetic outcomes, including a reduced gingival recession and interdental papillae reconstruction. The clinical results of the present case were well maintained over the 2-year follow-up.

The purpose of this case series was to report the clinical outcomes and histologic findings of vertical ridge augmentation using a combination of titanium mesh, resorbable collagen membrane, and recombinant human plateletderived growth factor BB (rhPDGF-BB). Nineteen patients were included, and autogenous bone and anorganic bovine bone particles were used. The bone graft was mixed with rhPDGF-BB and loaded onto the bony defect up to the level of the adjacent alveolar crest. A pre-adapted titanium mesh was placed over the grafted region and covered with a resorbable collagen membrane, leaving no areas of the grafted region exposed. Seventeen patients exhibited good soft tissue healing. Postoperative flap dehiscence occurred relatively early in the healing period in one patient, whereas the covering collagen membrane was exposed during the later phase of the healing period in another. During reentry surgery for removal of the titanium mesh, three patients with favorable soft and hard tissue healing underwent bone biopsies for histologic evaluation of the augmented tissue just below the titanium mesh. The mean vertical height of augmented bone was 8.6 ± 4.0 mm. This report demonstrates the remarkable efficacy of guided bone regeneration using a combination of titanium mesh, resorbable collagen membrane, and rhPDGF for vertical ridge augmentation, thus expanding the indications for implant therapy and allowing recovery of the three-dimensional esthetic architecture in a severely absorbed alveolar ridge.

Achieving an esthetic outcome in tooth replacement and implant treatment requires a proper tooth shape and stable surrounding soft tissue profiles. Bone augmentation is considered vital to support the esthetic soft tissue profile around definitive restorations. To prevent recession of the peri-implant soft tissue in cases with multiple implants, buccal bone augmentation of more than 2 mm from the implant platform is necessary to overcome the normal pattern of bone remodeling. Drawing an imaginary horizontal line spanning the space between the remaining healthy interproximal bone peaks is the most reliable vertical augmentation target to create esthetic papillae around an implant prosthesis. Provided that the adjacent bone peaks are at an ideal height and the bone is augmented vertically up to this line, the accepted general guideline of 2 to 3 mm of interproximal vertical bone augmentation from ideally placed implant platforms will invariably also be achieved. In addition, placing pontics in strategic positions to avoid consecutively placed implants has been suggested to facilitate vertical bone height preservation after bone augmentation. Even with esthetically successful results, there have been very few long-term studies on compromised cases with multiple implants. This will become more and more critical over time and must be remedied.

A single-tooth implant in the esthetic region has good potential for success, but it is still challenging to restore multiple-tooth defects with implant-supported prostheses that resemble the natural dentition. This article suggests a strategy to provide a more predictable protocol for esthetic implant treatment for multiple-tooth defects using the root submergence technique (RST). By maintaining the natural tooth root with the RST, a much greater amount of surrounding tissue may be preserved than with the commonly used socket preservation technique, which almost always leads to crestal bone resorption and thus reduction of the height of the interdental papillae and width of the edentulous ridge. RST instead maintains the natural attachment apparatus of the tooth in the pontic site, which in turn allows for complete preservation of the alveolar bone frame and assists in the creation of an esthetic result in adjacent multiple-tooth-replacement cases. In situations with periodontal bone loss, orthodontic extrusion is required to create the underlying bone support for the papilla that is necessary to guarantee predictability.

Many articles address the predictability of immediate implant placement into extraction sockets; however, there are only a few reports that mention the indications and limitations of this technique. The aim of this article is to re-examine specific indications for immediate implant placement and to clarify the timing or "fourth dimension" relative to extraction and implant placement. The expanded concept of four-dimensional implant treatment planning involves the new axis of time, which must be considered along with the traditional spatial or threedimensional management of implant positioning.