Correcting a qualitative or quantitative reduction in the bone bed before implantation can greatly improve the implant outcome. In addition to the gold standard of autologous bone grafting, the bone substitute materials currently available for this purpose can be subdivided into allogenic, xenogenic and alloplastic materials. Developments in the field of synthetic BSMs are constantly changing, and the selection of appropriate materials depends on the indication, availability and the individual treatment plan. The common goal of these BSMs is to achieve stable, long-term anchorage of the implants in the bone. A knowledge of the advantages and limitations of their principal properties in respect of osteoconduction, osteoinduction and osteogenesis, and the adequate selection, based on this knowledge, can ensure high-quality, evidence-based treatment. Introduction As well as the need for physical and mechanical integrity and stability in terms of adequate moldability during application, early load-bearing and ideal porosity, the focus of current research efforts is on the development of optimal biomolecular parameters in the area of osteogenesis (bone formation in the graft by osteoblasts), osteoconduction (creation of a scaffold for vascularization of the adjacent bone) and osteoinduction (differentiation of multipotent mesenchymal cells into osteoblasts, by proteins bound in the graft). In an ideal scenario, these parameters interact to achieve successful osteointegration of the BSM during the course of healing. In this case, the direct bonding of the bone substitute material to adjacent healthy bone without the formation of a separating layer of connective tissue can create the best possible basis for successful long-term implant provision. The implant-related indications determined by the dentist for the use of bone substitute materials predominantly involve horizontal and vertical bone defects of the alveolar ridge. Autogenous bone substitute materials Autogenous bone is considered to be the gold standard for hard tissue augmentation techniques. Apart from the physiological interaction between the aforementioned physical and mechanical parameters and outstanding performance in terms of osteoinduction, osteoconduction and osteogenesis, the use of autologous bone avoids complications such as contrary cellular and humoral immune reactions and transmission of diseases. However, the use of these grafts is associated with certain limitations: These include the need for a second intervention site with additional risks such as inflammation, pain or sensory disorders at the site of harvesting. Depending on the harvesting site (retromolar, mandibular symphysis, iliac crest), specific advantages and disadvantages in respect of the differing biological significance and the possible reconstruction volume will need to be taken into account [1, 2]. Although autogenous bone is still considered to be the gold standard for long-term implant success, studies involving specific indications, such as lateral augmentation or the sinus lift, have shown that the use of bone substitute materials can achieve equivalent results. Moreover, the procedure of autogenous bone harvesting can significantly prolong operation time and the hospitalization rate in cases of bone harvesting of the iliac crest [3, 4]. Allogenic bone substitute materials In order to counter the donor morbidity associated with the use of autogenous grafts, the use of allogenic grafts can be considered. Allogenic describes the transfer of the graft between genetically dissimilar individuals. Since the grafts count as medicinal products authorized e.g. by the Paul Ehrlich Institute in Germany or local accredited tissue banks, their use is guaranteed to be safe both for the therapist and patient. However, the risk of infection resulting from the transfer of biological tissue from human to human, as well as the risks of fractures or pseudarthroses associated with an allogenic graft, cannot be ruled out completely . Through stringend donor screening and recovery protocols, as well as a highly controlled processing environment, the risks of disease transmission are countered at every step. To date there are no known cases of transmission triggered by processed, freeze-dried bone preparations in dental applications. Two distinct approaches can basically be adopted for processing allogenic BSMs: The material is freed from a given mineralized bone substance by decalcification in order to optimize the osteoinduction potential of the remaining growth factors in the collagen. This approach of demineralized bone matrix (DBM, also known as demineralized freeze-dried bone allograft, DFDBA), can be contrasted with the processing of the mineralized components of the donor tissue (mineralized freeze-dried bone allograft, FDBA). In this approach the tissue is freed of potentially infectious or immunologically active constituents. This leaves the natural bone structure with the trabecular matrix, with preservation of both the organic phase (collagen) and the mineral phase. (Click on the image for a larger resolution) Cancellous Allograft Particles used as dental bone substitute. Cortical AlloGraft Particles used as dental bone substitute. Since the physical and mechanical properties are equivalent to those of autogenous graft, allogenic BSM is considered to be comparable with autologous bone in respect of its osteoconductivity potential. One bone substitute material of human origin that is available in many European countries is the product maxgraft® from botiss biomaterials GmbH. This processed allogenic bone substitute is available in different standardized forms of granules, blocks, rings etc., or alternatively as an individually milled and shaped block graft, and can therefore be used for various indications. In case of large defects, a block-like matrix can be prepared from processed human donor bone, thus avoiding invasive harvesting of bone from the iliac crest or cranial areas. After organ donor selection and donor testing for infectious agents like HIV, HBV and HCV, the BSM undergoes chemical cleaning, preparation and sterilization. A solution tailored to the individual defect involves the use of a patient-specific bone block that is planned on the basis of imaging and then milled (maxgraft® bonebuilder, botiss biomaterials GmbH). As an individual allogenic graft solution, individual implants customized for the patient can be created by means of CBCT scanning in the CAD/CAM technique. These are constructed by botiss and then produced by the “Cells and Tissuebank Austria (CTBA)”. As a prefabricated ring structure (maxgraft® bonering), the allogenic graft supplied by the company botiss allows the bone augmentation and implantation to take place at the same time, avoiding the need for a second procedure. These grafts can be used in sinus floor augmentations or horizontal and vertical bone defects with simultaneous implant provision. The latest literature findings show results comparable with the use of demineralized allogenic BSM in sinus floor augmentations. The results of evidence-based studies also support the use of this type of BSM for alveolar ridge augmentations, intrabony defects and implant provision [6-9]. Xenogenic bone substitute materials In contrast with an allogenic BSM, xenogenic tissue is of animal or plant origin. In this context, BSMs of bovine origin are by far the most widely used materials. As with allogenic bone substitute materials, the matrix component is left in place during the processing of xenogenic grafts in order to control osteoconduction. The trabecular framework remains after thermal processing. Here, the osteoconductivity of the tissue as a scaffold for vessel formation and subsequent ingrowth of osteoblasts in the graft are particularly advantageous. As a result, biomolecular effective components are deactivated, leaving a matrix of hydroxyapatite ceramic. The lack of pathogen transmission due to this deactivation process is particularly beneficial. Additionaly, the immunological action can be considered to be low. Most of the commercially available products are designed to create a trabecular matrix for the formation of new bone. One example is cerabone® (botiss biomaterials GmbH), a material processed from bovine bone. Bone substitute materials obtained from equine bone or marine algae are also available. By far the most scientific evidence is available for the group of bovine xenogenic BSMs. Bovine bone material possesses physical and mechanical properties that are similar to those of human bone, thus comparable results can be achieved in terms of osteoconduction and vascularization. (Click on the image for a larger resolution) botiss® cerabone®: bovine dental bone substitute; surface structure of a single particle in high magnification botiss® cerabone®: bovine dental bone substitute; surface structure of a single particle in high magnification Product presentation botiss® cerabone® Cerabone® is prepared by a unique high-temperature process that reliably removes potential infectious agents while at the same time preserving the natural cancellous bone structure. Due to the remaining trabecular support structure a maintenance of the original bone substitute volume can be achieved. [10, 11]. The advantages of cerabone® include its high purity and volume maintenance, an interconnecting pore structure and minimization of the infection risk by its processing . A feature common to all BSMs of bovine origin is the comparatively low remodeling potential during healing. As a result, the bone substitute material remains in situ as a slowly-resorbable osteoconductive scaffold. Alloplastic bone substitute materials Alloplastic bone substitute consists of synthetically produced materials. By imitating the trabecular bone matrix of human bone, the synthetic material possesses similar osteoconductive and osteointegrative capabilities. Depending on the starting material, the alloplastic materials can be subdivided as follows: ceramics (tricalcium phosphate, hydroxyapatite, bioglasses, glass ionomers), polymers (polymethyl methacrylate, polylactides/polyglycolides and other copolymers), cements (calcium phosphate cements) and metals (titanium). Durability and resorbability are particularly important when selecting these materials. Ceramics Alloplastic hydroxyapatite ceramics [Ca10(PO4)6(OH)2] are the most common representatives of this group. The sintering of calcium phosphates (hydroxyapatit (HA), alpha-tricalcium phosphate (α-TCP) and beta-tricalcium phosphate (β-TCP)) produces a biocompatible, non-immunogenic and a slowly-resorbable matrix with osteoconductive and osteointegrative properties [13-16]. Since hydroxyapatite in crystalline form provides the basis for the hard substance of human bone, making up around 40 % of its content, ceramics of this type are likely candidates for use in bone replacement. Innovative sintering techniques can create the conditions that are favorable for osseointegration and biodegradation. Here, pore diameters of 150–600 μm are considered to be ideal for these purposes . (Click on the image for a larger resolution) botiss® maxresorb®: synthetic dental bone substitute; surface structure of a single particle in high magnification. Product presentation botiss® maxresorb®. A fully synthetic commercially available representative of this group is maxresorb® (botiss biomaterials GmbH). Consisting of 60% hydroxyapatite (HA) and 40% beta-tricalcium phosphate (ß-TCP), maxresorb® possesses a uniform interconnecting pore structure thanks to the standardized manufacturing process. With pore sizes ranging from 200 to 800 μm and an overall porosity of ~80%, it provides a suitable scaffold for vascularization and cell migration . Indications for the dentist in practice Returning to the initially mentioned indications for the use of bone substitute materials in implantology, the following recommendations can be made on the basis of the latest guideline on “Implantology-related indications for the use of bone substitute materials”: Dehiscence defect (intrabony defect): In most cases, the use of BSMs resulted in complete defect regeneration. Horizontal/vertical defects: The use of BSMs produced horizontal (3.6–5.6 mm) and vertical (2.0–5.6 mm) dimensional gains after 6 months with values of less than 5 % for augmentation and implant losses. Xenogenic BSMs were superior to allogenic grafts in respect of the newly-formed bone. Sinus floor elevation: Xenogenic BSMs (95.6 %) and allogenic BSMs (93.3 %) were superior to alloplastic materials (81 %). External sinus floor elevation: The use of BSMs resulted in a cumulative implant survival rate of almost 97 %. Autologous bone is inferior to particulate grafts. Internal sinus floor elevation: The use of BSMs resulted in implant survival rates of 94.8-100 %. No general recommendation was issued for the use of BSMs in this context. It can therefore be assumed that the use of alloplastic bone substitute materials can achieve very good results particularly in the management of alveolar dehiscence defects (up to a height of 8mm) and also in sinus floor elevations. Augmentations with purely allogenic grafts in the whole vertical-horizontal situation and for fairly large defects should be handled more critically. Current recommendations point to the benefits of additive supplementation with allogenic BSMs in procedures with autologous bone substitute materials. Extensive defects should generally be reconstructed with large-pore BSMs, ideally with pore diameters in the range of 150 to 600 μm, in order to facilitate better neovascularization, cell permeation and osteoconduction. Summary Depending on the individual indication, the dentist can currently choose from a wide range of evidence-based bone substitute materials. Both natural and allogenic BSMs can basically be used, either on their own or in addition to endogenous bone, for the reconstruction of jaw defects. To this end, the advantages and disadvantages and possible contraindications of the respective material groups will need to be assessed and used on a case-by-case basis. Before planning the treatment, the dentist must conduct an individual, patient-oriented evaluation of the osteogenic efficiency and relative risks for the patient arising from the use of allogenic or xenogenic bone substitute materials. Given the complexity and diversity of the subject of “bone substitute materials”, careful and comprehensive briefing of the patient is extremely important before any augmentation measure, regardless of the material that is ultimately used. Relative and, where applicable, absolute contraindications to the use of alloplastic materials are an immunocompromised patient (immune deficiency, interleukin-1 polymorphisms), generally poor oral hygiene (dental status not worth preserving, severe chronic periodontitis), treatment with drugs that inhibit bone resorption (bisphosphonates) and previous oral-maxillofacial radiotherapy. Finally, it should be stressed that the correct technique is of crucial importance when using the respective bone substitute material. Apart from the choice of suitable bone substitute material, key factors for long-term success of the implant are the membrane application, the appropriate incisions and the soft tissue management. References Z. Sheikh, S. Najeeb, Z. Khurshid, V. Verma, H. Rashid, and M. Glogauer, “Biodegradable Materials for Bone Repair and Tissue Engineering Applications,” Materials 8(9), 5273 (2015). D. E. Tolman, “Reconstructive procedures with endosseous implants in grafted bone: a review of the literature,” Int J Oral Maxillofac Implants 10(3), 275-294 (1995). E. Nkenke and F. Stelzle, “Clinical outcomes of sinus floor augmentation for implant placement using autogenous bone or bone substitutes: a systematic review,” Clin Oral Implants Res 20 Suppl 4(124-133 (2009). M. Peleg, A. K. Garg, C. M. Misch, and Z. Mazor, “Maxillary sinus and ridge augmentations using a surface-derived autogenous bone graft,” J Oral Maxillofac Surg 62(12), 1535-1544 (2004). K. U. Gomes, J. L. Carlini, C. Biron, A. Rapoport, and R. A. Dedivitis, “Use of allogeneic bone graft in maxillary reconstruction for installation of dental implants,” J Oral Maxillofac Surg 66(11), 2335-2338 (2008). G. Chaushu, O. Mardinger, S. Calderon, O. Moses, and J. Nissan, “The use of cancellous block allograft for sinus floor augmentation with simultaneous implant placement in the posterior atrophic maxilla,” J Periodontol 80(3), 422-428 (2009). G. Chaushu, M. Vered, O. Mardinger, and J. Nissan, “Histomorphometric analysis after maxillary sinus floor augmentation using cancellous bone-block allograft,” J Periodontol 81(8), 1147-1152 (2010). A. Acocella, R. Bertolai, E. Ellis, 3rd, J. Nissan, and R. Sacco, “Maxillary alveolar ridge reconstruction with monocortical fresh-frozen bone blocks: a clinical, histological and histomorphometric study,” J Craniomaxillofac Surg 40(6), 525-533 (2012). R. A. Wood and B. L. Mealey, “Histologic comparison of healing after tooth extraction with ridge preservation using mineralized versus demineralized freeze-dried bone allograft,” J Periodontol 83(3), 329-336 (2012). F. Riachi, N. Naaman, C. Tabarani, N. Aboelsaad, M. N. Aboushelib, A. Berberi, and Z. Salameh, “Influence of material properties on rate of resorption of two bone graft materials after sinus lift using radiographic assessment,” Int J Dent 2012(737262 (2012). D. Panagiotou, E. Ozkan Karaca, S. Dirikan Ipci, G. Cakar, V. Olgac, and S. Yilmaz, “Comparison of two different xenografts in bilateral sinus augmentation: radiographic and histologic findings,” Quintessence Int 46(7), 611-619 (2015). D. Tadic and M. Epple, “A thorough physicochemical characterisation of 14 calcium phosphate-based bone substitution materials in comparison to natural bone,” Biomaterials 25(6), 987-994 (2004). M. Bohner, “Calcium orthophosphates in medicine: from ceramics to calcium phosphate cements,” Injury 31 Suppl 4(37-47 (2000). H. Schliephake, N. Zghoul, V. Jager, M. van Griensven, J. Zeichen, M. Gelinsky, and T. Wulfing, “Effect of seeding technique and scaffold material on bone formation in tissue-engineered constructs,” J Biomed Mater Res A 90(2), 429-437 (2009). S. Takagi, L. C. Chow, M. Markovic, C. D. Friedman, and P. D. Costantino, “Morphological and phase characterizations of retrieved calcium phosphate cement implants,” J Biomed Mater Res 58(1), 36-41 (2001). R. Smeets, A. Kolk, M. Gerressen, O. Driemel, O. Maciejewski, B. Hermanns-Sachweh, D. Riediger, and J. M. Stein, “A new biphasic osteoinductive calcium composite material with a negative Zeta potential for bone augmentation,” Head Face Med 5(13 (2009). M. Hallman and T. Nordin, “Sinus floor augmentation with bovine hydroxyapatite mixed with fibrin glue and later placement of nonsubmerged implants: a retrospective study in 50 patients,” Int J Oral Maxillofac Implants 19(2), 222-227 (2004). K. Zurlinden, M. Laub, D. S. Dohle, and H. P. Jennissen, “Immobilization and Controlled Release of Vascular (VEGF) and Bone Growth Factors (BMP-2) on Bone Replacement Materials,” in Biomedical Engineering / Biomedizinische Technik, (2012), p. 989. Prof. Ralf Smeets Dr. med. Dr. med. dent Executive Senior Physician and Head of Research, University Medical Center Hamburg-Eppendorf, Head and Neurocenter of the Clinic and Outpatients for Oral and Maxillofacial Surgery, Hamburg, Germany Studied chemistry (specialist subject: macromolecular chemistry) and human medicine and dentistry at RWTH Aachen University. Surgeon specialized in oral and maxillofacial surgery. Dentist specialized in oral surgery Hans-von-Seemen Prize awarded by the German Association for Plastic and Restorative Surgery. Since 2011, Executive Senior Physician and Head of Research in the Clinic and Outpatients for Oral and Maxillofacial Surgery, University Medical Center Hamburg-Eppendorf. 2011 W2 University Professor of Maxillofacial and Oral Surgery in the Medical Faculty of Hamburg University. The post Augmentation of hard tissue – an overview of regenerative techniques in dentistry appeared first on STARGET COM.
The following case report illustrates from experience how one-piece all-ceramic implants with one surface are comparable to the very well-documented Straumann® SLA® surfaces. The dental implant treatment in the anterior maxillary region took place in collaboration with Dr. Bettina Koch-Heinrici (Hamburg), who carried out the prosthetic restoration. PRODUCT INFORMATION BY THE MANUFACTURER The Straumann® PURE Ceramic Implant is the result of more than 9 years of research and development. It has a natural looking ivory color, a feature that makes the implant look more like a natural tooth and supports the clinician in cases of thin gingiva biotype or soft tissue recession. It has a monotype design based on features of the Straumann® Soft Tissue Level Standard Plus and Straumann® Bone Level Implants. According to a survey (data on file at Straumann), patients would prefer tooth-colored implants, if given the choice between ceramic and metal implants. With the Straumann® PURE Ceramic Implant, clinicians can offer their patients a natural and highly esthetic solution, benefitting from favorable soft tissue attachment around zirconia implants. MORE? All about the STRAUMANN® PURE CERAMIC IMPLANT on STARGET at a glance. Click here PICTURE DOCUMENTATION Fig. 1 The orthopantomogram shows the preoperative starting position (approximately three months after the removal of teeth 21, 22, 11) Fig. 2 Intraoperative initial clinical position Fig. 3 Situation after six months of healing and preparation of drilling channels to accommodate the implants Fig. 4 Insertion of Straumann Pure Ceramic implants in the region of 11, 22, 23 (diameter 4.1 mm; in the region of 22, a reduced diameter implant was used.) Fig. 5 Orthopantomogram - recorded postoperatively, implants in situ Fig. 6 Front view of inserted ceramic crowns INTRODUCTION Over the last few years, there has been increasing demand from patients for completely metal-free (implant) provision, and many patients prefer ceramic to titanium implants . All-ceramic prosthetic restoration with ceramic implants results esthetically in a natural dental and mucosal appearance, for example in patients with a thin gingival biotype or a high smile line [3.10]. In addition, in our practice, patients who are intolerant to titanium and have elsewhere described “chronic fatigue syndrome” symptoms following titanium implant insertion have indicated their wish for a metal-free alternative to titanium implants. Specialized information issued by the Institute for Medical Diagnostics in Berlin, has concluded that titanium intolerance is not an allergy, but rather the result of an increased propensity to infection of tissue macrophages on titanium oxide particles [12, 14, 16]. I offer my patients a blood test to determine titanium intolerance. In patients with positive findings, delayed or impaired healing of dental titanium implants can result, where even the macrophages in the implantation area can react hyperactively to released titanium particles and trigger both local and systemic inflammation. My basic motivation in our referral practice is to offer our patients implants, which, wherever possible, do not burden bone or the immune system. With this in mind, I have made increased use of ceramic implants. A great advantage of ceramics is their biocompatibility. With regard to the healthy maintenance of peri-implant tissue, it is extremely beneficial to monitor early plaque accumulation on zirconium dioxide . This results in less gingival recession, and the formation of the papilla around the implant is more esthetically pleasing [9, 15]. Zirconium oxide implants have a lower tendency to extended peri-implant infections . SPECIAL SURFACE ZIRCONIA CERAMICS The Straumann® Pure Ceramic Implant impressed me particularly in this respect. It consists of a one-piece implant body made of 100% high-performance zirconia ceramic (Y-TZP). Its shape is based on features of both the Straumann® Soft Tissue Level Standard Plus and bone level implants. In the past three years, the proportion of ceramic implants inserted, compared with recent insertions using titanium implants, has risen steadily in our practice and is currently at about 60 percent. I have since placed 300 Straumann® Pure Ceramic implants and, in our referral practice, I only recommend ceramic implants to my patients. Straumann’s background, combined with over 60 years of experience in material innovation, gives me confidence as a user and offers safety in treatment. With the official launch of the one-piece implant following a seven-year development process, Straumann offers an all-ceramic implant system with reliable, scientific processing for predictable treatment success [2,10]. The Straumann® ZLA® ceramic implant surface is characterized by macro- and micro-roughness, which is similar to the topography of the proven Straumann® SLA surface (SLA stands for sand-blasted, large-grit, acid-etched). Animal studies have shown osseointegration with respect to peri-implant bone density and BIC value (bone to implant contact), which corresponds to Ti-SLA [5, 11]. The SLA surface is one of the best documented rough surfaces in implantology and, due to its osseointegration properties, reduces the healing time of implants [4, 6]. Studies show a much improved accumulation of fibroblasts on the ceramic surface and subsequently a good soft tissue graft is expected [8, 18]. FINDINGS AND PLANNING A 28-year-old patient was transferred to our practice with an unremarkable general history: He had a naturally healthy bite, but was dissatisfied with the esthetics and chewing function of the upper jaw. Teeth 11, 21 and 22 had been endodontically treated after trauma to the front teeth suffered as a child. Due to complications, multiple apicoectomies were carried out and, over a period of ten years, there has been severe bone resorption in the anterior maxillary region. After a discussion on possible treatment options (from removable dentures or bridge to titanium implants), the request was quickly made for completely metal-free treatment following the extraction of teeth 11, 21 and 22. I made the patient aware of possible compromised gingival esthetics, as even a three-dimensional bone graft can result in dehiscence, and further augmentation may be necessary. Both the patient and his family dentist agreed with the metal-free treatment concept. About three months after extraction of teeth 11, 21 and 22, a CBCT was prepared to evaluate bone and subsequently show the reconstruction to the patient using photographic examples. After scheduling the procedure, the patient was fitted with a temporary form by the family dentist. Then a new CBCT was made using a template and from this, three Straumann® Pure Ceramic implants were navigated and inserted (region of 11, 21: endosteal diameter 4.1 mm; region of 22: diameter-reduced ceramic implant 3.3 mm). A navigated procedure is the basic prerequisite for successful insertion and prosthetic implant care. Given that it is a one-piece implant system, detailed planning of the spatial position of the implant by prosthetically orientated “backward planning” is required. Unlike with two-piece implants, angled construction axis correction is subsequently not possible. However, the one-piece design offers an outstanding advantage: Due to its one-piece design, a micro-gap within the implant is eliminated, which reduces the risk of the patient developing periimplantitis. TREATMENT PROCEDURE For the three-dimensional reconstruction, I removed autologous bone from the jaw angle region and cut it into thin slices. An outer contour was subsequently reconstructed and then the new bone walls were screwed at a distance. PRGF bone chips were mixed and condensed into the gap. If the gap is too large, in our practice we use Straumann® Bone Ceramic, a synthetic bone substitute material. This supports the regeneration of vital patient bone and at the same time restores and retains bone volume. In this case, a collagen membrane was used. After an approximate six-month healing period, guided implant placement was carried out. This allowed precise insertion of a one-piece zirconia implant in the correct axial alignment (drilling protocol corresponded to the bone level implant). Pure Ceramic implants are available with an endosteal diameter of 4.1 mm and a reduced diameter of 3.3 mm, as well as in two heights and four implant lengths of 8, 10, 12 and 14 mm. Please note: The implant body cannot be ground down at a later date. Any microcracks would reduce the breaking strength. Therefore, great care must be taken during pre-implant diagnostics and planning in the selection of the height of the prosthetic platform (here 5.5 mm). After a period of approximately four months of implant healing with temporary forms, implant care was provided by the family dentist Dr. Bettina Koch-Heinrici. The zirconium framework was constructed and milled using CAD/CAM (milling by Amman Girrbach), blending was carried out using Creation Zi-CT leucite crystal containing feldspar ceramic (Willi Geller). CONCLUSIONS FOR CLINICAL PRACTICE I am completely convinced by these zirconia implants with special surface features: I am able to offer my patients a product that, as far as possible, does not burden bone or the immune system, has excellent esthetic and mechanical properties and, due to its one-piece design, only a single intervention is required, trauma is minimized and subsequent morbidity reduced, and in addition, due to its one-piece design, the risk of the patient developing periimplantitis is reduced. The one-piece Straumann® Pure Ceramic implant is both user-friendly and patient-friendly and has the advantage of scientifically supported results and a reduced diameter option. In my opinion, for the benefit of patients, metal-free restorations should become routine for implantology. I am willing to be part of a research team: As far as I’m concerned they are already the “next generation of dental implants” . Note: this case report is the English translation of an article first published in “DZW Orale Implantologie 3/16, Fachmagazin zur DZW – Die ZahnarztWoche”, Germany – No. 42/16, October 2016. References  Barfeie A, Wilson J, Rees J. Implant surface characteristics and their effect on osseointegration. Br Dent J. 2015 Mar 13;218(5):E9. doi: 10.1038/sj.bdj.2015.171.  Becker W. Neues Keramikimplantat von Straumann. Dent Implantol 2014:18,3,230-231.  Bidra AS, Rungruanganunt P. Clinical outcomes of implant abutments in the anterior region: a systematic review. J Esthet Restor Dent. 2013 Jun;25(3):159-76. doi:10.1111/jerd.12031. Epub 2013 May 3.  Bischof M, Nedir R, Abi Najm S, Szmukler-Moncler S, Samson J. A five-year life-table analysis on wide neck ITI implants with prosthetic evaluation and radiographic analysis: results from a private practice. Clin Oral Implants Res. 2006 Oct;17 (5): 512-20.  Bormann KH, Gellrich NC, Kniha H, Dard M, Wieland M, Gahlert M. Biomechanica evaluation of a microstructured zirconia implant by a removal torque comparison with a standard Ti-SLA implant. Clin Oral Implants Res. 2012 Oct; 23(10):1210-1216.  Cornelini R, Cangini F, Covani U, Barone A, Buser D. Immediate loading of implants with 3-unit fixed partial dentures: a 12-month clinical study. Int J Oral Maxillofac Implants. 2006 Nov-Dec; 21(6):914-8.  Engelhardt-Wölfler H. Patientenstudie Basel-München. Abschlussbericht: Verhaltensanalysen durch Prof. Dr. Henriette Engelhardt-Wölfler, Universität Bamberg, aus: Mehr als PURE Ästhetik. Die natürliche, stabile Versorgung. Starget 2014:1,35-39.  Erbshäuser M. Einteiliges Keramikimplantat im ästhetisch sensiblen Frontzahnbereich – die richtige Alternative zu bewährtem Titan? Implantologie Journal 2016 (11):32-40.  Gahlert M, Kniha H, Weingart D, Schild S, Gellrich NC, Bormann KH. A prospective clinical study to evaluate the performance of zirconium dioxide dental implants in single-tooth gaps. Clin Oral Implants Res. 2015 Apr 1. doi:10.1111/clr.12598. [Epub ahead of print].  Gahlert M, Kniha H, Weingart D, Schild S, Eickholz P, Nickles K, Bormann K-H (Gemeinschaftspraxis Kniha/Gahlert, Munich, Germany). Prospective Open Label Single Arm Study to Evaluate the Performance of The Straumann PURE Ceramic Implant in Single Tooth Gaps in the Maxilla and Mandible. Poster 252 beim 22. Wissenschaftlichen Jahreskongress der European Association of Osseointegration, 17.-19. Okt. 2013, Dublin, Irland.  Gahlert M, Roehling S, Sprecher CM, Kniha H, Milz S, Bormann K. In vivo performance of zirconia and titanium implants: a histomorphometric study in mini pig maxillae. Clin Oral Implants Res. 2012 Mar;23(3):281-6. doi:10.1111/j.1600-0501.2011.02157.x. Epub 2011 Aug 2. Dr. med. dent. Tobias Wilck Dr. Tobias Wilck has been a specialist in implantology, oral and maxillofacial surgery since 2004. After studying medicine in his hometown of Hamburg, he gained international experience in Kingston (Jamaica) and Vienna before studying dentistry in Hamburg and Tübingen, where he also worked as a training assistant. He completed specialist training in Hamburg and Tübingen, as well as in Krefeld-Uerdingen, where he was most recently employed as a senior physician. In recent years, Dr. Wilck has been involved in humanitarian work in Vietnam (University of Hanoi), caring for facially disfigured children, primarily with cleft lips and palates. CLINICAL REVIEW The clinical facts behind the Straumann® PURE Ceramic Implant. BROCHURE Download the brochure for the Straumann® PURE Ceramic Implant. SUBSCRIBE Subscribe to our monthly STARGET newsletter to receive the latest news about implant dentistry. The post Tobias Wilck: One-piece and esthetically sensitive ceramic implants for the front teeth area (Straumann® Pure Ceramic Implant) appeared first on STARGET COM.
Dental implant prosthetics or, more precisely, the process of abutment selection is often perceived as highly complex. But as soon as the patient’s clinical needs are brought back to the center stage of abutment selection, it becomes evident that the Straumann prosthetic range is not about “everything does everything” but about clear criteria for specific indications. With this in mind, Straumann has developed a new abutment selection concept that benefits all kinds of expert levels, making the selection process significantly more transparent and comprehensible. While experienced users may be aware that Straumann offers more options than they believed, less experienced users receive helpful guidance on how to make the “perfect choice” for their indication. Prosthetic complexity is just a matter of perception Dental implant prosthetics is often perceived as highly complex. Looking at the official Straumann® Prosthetic System “Who is who”, one is reminded of the wiring diagram of a nuclear power plant control room. But, in the case of prosthetics, it’s just a perception, and with the right approach things suddenly become much more straightforward! The search for the appropriate selection criteria The perception of prosthetic complexity is actually largely related to the impression that “everything does everything”. Therefore, the selection of the right abutment can be perceived as quite difficult when there is no clear selection path. But in fact, products were designed for specific clinical situations, with some products being close indication-wise, but actually with very distinctive features and benefits. Straumann has evaluated this issue with the aim of better supporting and improving the selection process in daily practice. We are convinced that the identification of the right product is actually quite straightforward if the appropriate selection criteria are applied. Initial assumption: the patient takes center stage! We refocused our attention on the patient as, in every case, the surgeon, the dentist, and the dental lab are confronted with a patient whose dental issue needs to be solved in the most accurate and professional way. This patient does not need a product but rather a restorative solution for his/her single tooth, bridge, or edentulous maxilla or mandible. Identifying the right abutment in just two steps? Based on these considerations, we have introduced a new simple way to select the right abutment. We call it simple because this approach is based on a clinical situation and because it consists of just two steps. SEE IT IN ACTION Visit your local Straumann website and experience the beauty and simplicity of an indication-based abutment choice. Example: Straumann UK Click here THE TWO STEPS TO THE RIGHT ABUTMENT Step 1 – type selection: bone level or tissue level implant | single tooth, bridge or full- arch and, depending on the clinical situation or user preference, the prosthetic retention method: screw- or cement-retained for single teeth and multi-units | fixed or removable for full-arch prostheses. Step 2 – one size does not fit all: Since not all similar clinical situations need exactly the same abutment, the selecting professional is guided to the solution by replying to a few questions related to the user’s preferences, like fully customized or standard abutment = digital or conventional workflow | the specific patient’s situation (esthetic needs, available budget, etc.). The post Prosthetic selection guide by clinical situation: select the right Straumann® abutment in just two steps appeared first on STARGET COM.
The patient was treated for recurrent failure of her fixed dental prosthesis over several years. She was very upset with her situation because she works as a sales assistant in a department store and relies on impeccable function and aesthetics of her dentition. The female patient was 61 years old when she presented at our clinic. She was a non-smoker in very good general health and did not take any medication. However, she felt anxious about dental treatment in general. Coauthor: Patrick Zimmermann, Dental Technician, from Zahnmanufaktur, Bern, Switzerland. PRODUCT INFORMATION BY THE MANUFACTURER The Straumann® Novaloc® Retentive System for hybrid dentures offers an innovative carbon-based abutment coating (ADLC, amorphous diamond-like carbon) with excellent wear resistance, overcoming up to 60° implant divergence. Both a straight and a 15° angled abutment, available in various gingiva heights, cover a broad range of clinical implant situations. Together with its durable PEEK (Polyether ether ketone) matrices, the Novaloc® Retentive System provides a reliable connection that endures. This results in low maintenance and high patient comfort. Novaloc® is a registered trademark of Valoc AG, Switzerland. For availability information in your country contact your official Straumann representative. MORE? All about the STRAUMANN® NOVALOC® RETENTIVE SYSTEM on STARGET at a glance. Click here PICTURE DOCUMENTATION Fig. 1 schimmel01 Fig. 2 schimmel02 Fig. 3 schimmel03 Fig. 4 schimmel04 Fig. 5 schimmel05 Fig. 6 schimmel06 Fig. 7 schimmel07 Fig. 8 schimmel08 Fig. 9 schimmel09 Fig. 10 schimmel10 Fig. 11 schimmel11 Fig. 12 schimmel12 INITIAL SITUATION There were no signs or history of temporomandibular disorders, and mouth opening was normal at 43mm. Thus, the access to the oral cavity was adequate, and even the posterior sites could be reached without restriction. There were no signs of abnormal occlusal activity such as bruxism. Intraorally, the patient presented with failing dentition in the upper jaw. Over the course of the last few years several tooth-borne fixed dental prostheses had failed. At the time of the first consultation she wore a provisional overdenture that covered the roots of teeth UR3, UR2, UR1, UL1 and UL2. The molar UL6 was also present. All the remaining tooth structures in the maxilla were largely affected by caries and heavily restored. In the lower jaw an intact dental arch from LL5 to LR5 was present. The periodontal condition was healthy, with no signs of inflammation and probing depths < 3mm. Functionally, the patient was satisfied with the shortened dental arch. The aesthetic assessment showed a round, symmetrical face with evenly distributed facial compartments. The patient had a medium to high lip line and exposed some mucosa in the upper anterior region when smiling without the provisional prostheses. The buccal corridor was narrow and the gaps in the lower molar region were barely visible. TREATMENT PLANNING The patient’s expectations were realistic and comprehensible; her wish was to be able to participate in the activities of daily living without constantly worrying about her dental condition. The removal of all remaining roots and teeth from the maxillary jaw was indicated. As the patient was already accustomed to wearing a removable dental prosthesis (RDP), the provision of an overdenture with horseshoe design retained by four unsplinted attachments on four implants was proposed to the patient. From the prosthodontic standpoint, there were several considerations that led to this proposal. The patient presented a medium to high smile line and exposed the transition area between the prosthesis and mucosa when she smiled. This can occur especially in fresh extraction sites and indicates that the atrophy of the alveolar bone is not very pronounced (Tallgren 1972). Thus, it seemed easier to restore aesthetics with a buccal flange of an overdenture. An unsplinted, very small stud-type attachment was also indicated because of the restricted vertical space. An RDP retained by a milled bar needs a minimum height of 12-14 mm and can severely interfere with phonetics. The Novaloc® stud-type attachment however demands very little space, since the female part is only 2.3mm high and 5.5mm in diameter. Thus, the Novaloc® attachment is one of the smallest suitable attachments available on the market. Consequently, the anterior third of the maxilla (phonation zone) can be designed functionally (Clark et al. 2006 20). Although some expert opinions demand the primary splinting of implants in the maxilla, no clear evidence exists in the literature demonstrating a higher survival rate for splinted implants (Schimmel et al. 2014). However, Cordaro et al. demonstrated a very high success rate for overdentures retained by four unsplinted stud-type attachments in the maxilla on narrow-diameter titanium-zirconium (Ti-Zr) implants (Cordaro et al. 2013 110). For a maxillary overdenture, a minimum number of four implants is advisable (Schley et al. 2013). From a surgical point of view, the patient presented with very narrow alveolar crests, especially in the posterior regions. In the premolar region the width of the alveolar crest was only 2-3 mm. In the maxillary molar region the width of the crest was sufficient for implant placement, although the bone height in the region was very limited at just 1 mm. The treatment plan was designed to provide the patient with a maxillary overdenture retained by four unsplinted Novaloc® attachments on four tissue-level TiZr implants. Therefore, the following treatment sequence was planned: 1. Extraction of the remaining roots and teeth in the maxilla, followed by a minimum healing phase of eight weeks. 2. Sinus floor elevation on both sides and guided bone regeneration in the canine regions, followed by a minimum healing phase of 6 months. 3. Placement of implants in the regions UR6/5, UR3, UL3, UL5/6. 4. Fabrication of the overdenture, starting three months after implant placement (conventional loading protocol). Taking all information into consideration, the current case was classified as “Complex” in the normative ITI SAC classification with low additional complexity/risk based on modifiers. The patient consented to the treatment plan after discussion of the alternatives and options. In comparison to fixed implant-supported prostheses, an implant overdenture also has advantages in terms of simplified hygiene and facilitated replacement of oral tissue (Feine et al. 1994). SURGICAL PROCEDURE The teeth and roots in the upper jaw were extracted in toto, and the existing denture was relined with tissue conditioner. After a sufficient healing time, the oral surgeon performed the augmentation procedures under local anesthesia. A ridge incision in the region UR7 to UL7 with two distal reliefs in the vestibule was performed. The mucoperiosteal flap was carefully raised, and bone chips were harvested with a bone scraper. The maxillary sinuses on both sides were opened with lateral windows, and the augmentation was performed with the bone graft mixed with bone xenograft in the ratio 1:1. In the canine regions the buccal cortical bone was perforated, and the bone graft was applied laterally and covered with a collagen membrane. After perforation of the periosteum the margins of the flap were fixed with simple interrupted sutures using Seralon® (5-0). The post-operative medication included ibuprofen 600mg and Aziclav 2x1gram/day and disinfectant mouthwash. After a sufficient healing time the implants (all Straumann, SP, 4.1mm, RN, SLAactive, TiZr, 10mm) were placed in the regions UR6, UR3, UL3, UL6 with good primary stability. A smaller bony defect in the UR3 region was covered with a mixture of bone chips and bone xenograft. The flap was sutured to allow for transgingival healing of the implants with adequate healing caps. Post-operative medication included ibuprofen 600mg, Aziclav 2x1gram/day and disinfectant mouthwash. After eight weeks healing time the implants showed high ISQ-values: UR6 (75), UR3 (77), UL3 (84), UL6 (86) and the oral surgeon referred the patient back to the prosthodontist for the reconstructive phase (Figs. 1 and 2). PROSTHETIC PROCEDURE An indirect prosthetic workflow was chosen. Accordingly, the correct height of the abutments was chosen with single-use try-in abutments. They click into the implant connection, and vertical marks allow for easy identification of the correct abutment (Fig. 3). It is strongly advisable to select the abutments clinically and not subsequently on the master cast. The height of the abutments was chosen to fulfill two requirements: First, the housing of the matrices should not touch the peri-implant mucosa to avoid trauma to the sensitive tissues. Therefore, the shoulder of the abutment should be placed at least 1mm above the mucosa (Fig. 4). The second consideration for the height selection comprises the path of insertion of the overdenture. In order to avoid interferences, the uppermost platforms of the abutments in one jaw should form an even plane, which ideally is parallel to the occlusal plane (Fig. 5). The technician provided special trays on the basis of preliminary alginate impressions. The impression posts were screwed in and their seating was carefully verified (Fig. 6). Subsequently, the impression was taken using the high-precision viscoelastic impression material Identium® (Kettenbach GmbH, Germany), which is a Vinylsiloxanether® (Fig. 7). The master cast was produced in a class IV stone that carried the appropriate implant analogs. On this master cast the occlusal wax rim was produced with already incorporated female parts to ensure maximum stability of the base plate. The anterior teeth were chosen from the Candulor NFC+® line (Candulor, Switzerland), form no. 660, shade M3, using the Candulor Alameter and Papillameter for determining the length of the upper lip and the anterior teeth. The Candulor Bonartic II TCR M3/06 were chosen as posteriors. The technician provided the set-up, and the patient consented to finalize the overdenture. In the lab, a reinforcement framework made out of PEEK (Peek Juvora by Amann Girrbach) was milled, and the PEEK housings of the Novaloc® attachment systems were bonded into this framework. The wax design of the overdenture was transformed into PMMA using the PMMA Candulor no. 34 and the Candulor Aesthetic blue colors 34, 53, 55 and 57. On delivery, the Novaloc® abutments were screwed into the implants and torqued with 35Ncm (Fig. 8), and the denture was fitted. FINAL RESULT The overdenture was finished with individualized pink resin on the PEEK framework in a horseshoe design with open palate. It was shaped with individual palatal rugae and incisive papilla to match the patient’s anatomy and to allow for correct phonetics and easy adaptation to the new intra-oral situation (Fig. 9). A light retention was chosen for the denture with the white Novaloc® PEEK retention inserts (Fig. 10), with approximately 750 grams of retention force. This retentive force was largely sufficient, as the overdenture was retained by four attachments. The patient was extremely pleased with the treatment and the outcome. Much to her surprise, the surgery only caused her little discomfort. The prosthetic treatment was straightforward with a functionally and aesthetically pleasing outcome (Fig. 11). After many years of suffering the patient was finally able to smile again (Fig. 12). CONCLUSION In conclusion, an RDP in the upper jaw can be retained by four unsplinted attachments, but the implants should be large and strong enough for this indication. Therefore, a possible recommendation is to use implants at least 10mm long made from a reliable alloy like TiZr. The Novaloc® abutments are sufficiently small to ensure a denture design that respects phonetics and aesthetics. The stud-type attachments in general are widely applicable clinically as long as both the female and male parts show favorable wear behavior. The new coating on the Novaloc® abutment shows consistent in-vitro results, and the PEEK matrices may also prove to be more wear-resistant than inserts made from polyethylene. Further in-vitro and in-vivo investigations of the promising attachment systems may confirm these initial positive clinical experiences. References Clark, J., Yallop, C. and Fletcher, J. (2006). An Introduction to Phonetics and Phonology Blackwell. Cordaro, L., Torsello, F., Mirisola di Torresanto, V. and Baricevic, M. (2013). “Rehabilitation of an edentulous atrophic maxilla with four unsplinted narrow diameter titanium-zirconium implants supporting an overdenture.” Quintessence Int 44(1): 37-43. Feine, J. S., de Grandmont, P., Boudrias, P., Brien, N., LaMarche, C., Tache, R. and Lund, J. P. (1994). “Within-subject comparisons of implant-supported mandibular prostheses: choice of prosthesis.” J Dent Res 73(5): 1105-11. Schimmel, M., Srinivasan, M., Herrmann, F. R. and Muller, F. (2014). “Loading protocols for implant-supported overdentures in the edentulous jaw: a systematic review and meta-analysis.” Int J Oral Maxillofac Implants 29 Suppl: 271-86. Schley, J.-S., Terheyden, H., Wolfart, S., Boehme, P., Gómez-Róman, G., Keese, E., Kern, M., Pilgrim, C., Reinhardt, S., Weber, A. and Schütte, U. (2013). “AWMF 083/010 – S3-Leitlinie: Implantatprothetische Versorgung des zahnlosen Oberkiefers.” http://www.awmf.org/leitlinien/detail/ll/083-010.html (10.11.2015). Tallgren, A. (1972). “The continuing reduction of the residual alveolar ridges in complete deture wearers: A mixed-longitudinal study covering 25 years.” J. Prosthet. Dent. 27: 120-32. Disclaimer The patient provided informed written consent to publish her pictures. The surgical treatment was paid by the patient. Martin Schimmel and Patrick Zimmermann have no direct or indirect financial relationship with Straumann Institute and did not receive any benefit in kind or cash for this report. The current case report was part of an agreement between the Division of Gerodontology (University of Bern) and Straumann Institute for the documentation of two clinical cases with the Novaloc® attachment systems. Straumann Institute provided the parts and indemnified the Division of Gerodontology and the dental laboratory (Zahnmanufaktur). Prof. Dr. med. dent. Martin Schimmel MAS Oral Biol. Department of Reconstructive Dentistry and Gerodontology, Division of Gerodontology, School of Dental Medicine, University of Bern, Switzerland. firstname.lastname@example.org The post Martin Schimmel: A maxillary overdenture retained by four Straumann® Novaloc® abutments appeared first on STARGET COM.