Preservação em próteses implantossuportadas: peri-implantite / reservation in implant-supported prostheses: Peri-implantitis

Resumo: A identificação e o tratamento da infecção ao redor do implante é uma etapa essencial na manutenção do implante osseointegrativo e isso reflete na vida útil da reabilitação. O principal objetivo do tratamento da peri-implantite é a utilização de métodos de descontaminação mecânica e química para eliminar a carga bacteriana na superfície do implante. O biofilme pode ser removido por métodos não cirúrgicos ou cirúrgicos. Nos casos mais graves, geralmente é necessário tratamento cirúrgico, cujo objetivo é corrigir o defeito ósseo existente, combinado com a aplicação do enxerto, para regenerar o tecido ósseo perdido no processo inflamatório. O propósito deste estudo é realizar uma revisão de literatura tendo como o tema preservação em próteses implantossuportadas: peri-implantite, a fim de guiar a conservação das reabilitações orais. Além de buscar maiores informações acerca do desenvolvimento da doença peri-implantar, bem como sua ligação com a doença periodontal e os fatores que contribuem para seu desenvolvimento. Para tanto, foram utilizados descritores como: “peri-implantite", "manutenção de implantes" e “ossointegração” nas bases de dados: Pubmed, Scielo, google acadêmico e Lilacs. Para possibilitar um melhor resultado, foram organizados tópicos para uma discussão final, sendo eles: conceito, etiologia, diagnóstico e tratamento. Foram encontradas dificuldades na manutenção dos implantes e a necessidade de se descrever o melhor planejamento para uma melhoria nos protocolos clínicos de preservação a fim de obter-se excelência nos desfechos clínicos.Abstract: The identification and treatment of infection around the implant is an essential step in the maintenance of the osseointegrative implant and this reflects on the lifetime of the rehabilitation. The main objective of peri-implantitis treatment is the use of mechanical and chemical decontamination methods to eliminate the bacterial load on the implant surface. Biofilm can be removed by non-surgical or surgical methods. In more severe cases, surgical treatment is usually necessary, the aim of which is to correct the existing bone defect, combined with the application of a graft, to regenerate the bone tissue lost in the inflammatory process. The purpose of this study is to conduct a literature review with the theme of preservation in implant-supported prostheses: peri-implantitis, in order to guide the conservation of oral rehabilitations. In addition to seeking more information about the development of peri-implant disease, as well as its connection with periodontal disease and the factors that contribute to its development. For this purpose, descriptors such as: “peri-implantitis”, “implant maintenance” and “bone integration” were used in the following databases: Pubmed, Scielo, academic Google and Lilacs. final discussion, namely: concept, etiology, diagnosis, and treatment. Difficulties were found in the maintenance of implants and the need to describe the best planning for an improvement in clinical preservation protocols in order to obtain excellence in clinical outcomes. Plaque control maintains the health of the soft tissue-implant interface.Keywords: Dental implants; Peri-implantitis; Bacterial plaque.

Can activated titanium interbody cages accelerate or enhance spinal fusion? a review of the literature and a design for clinical trials

While spinal interbody cage options have proliferated in the past decade, relatively little work has been done to explore the comparative potential of biomaterial technologies in promoting stable fusion. Innovations such as micro-etching and nano-architectural designs have shown purported benefits in in vitro studies, but lack clinical data describing their optimal implementation. Here, we critically assess the pre-clinical data supportive of various commercially available interbody cage biomaterial, topographical, and structural designs. We describe in detail the osteointegrative and osteoconductive benefits conferred by these modifications with a focus on polyetheretherketone (PEEK) and titanium (Ti) interbody implants. Further, we describe the rationale and design for two randomized controlled trials, which aim to address the paucity of clinical data available by comparing interbody fusion outcomes between either PEEK or activated Ti lumbar interbody cages. Utilizing dual-energy computed tomography (DECT), these studies will evaluate the relative implant-bone integration and fusion rates achieved by either micro-etched Ti or standard PEEK interbody devices. Taken together, greater understanding of the relative osseointegration profile at the implant–bone interface of cages with distinct topographies will be crucial in guiding the rational design of further studies and innovations.

Sustained Release of VEGF to Promote Angiogenesis and Osteointegration of Three-Dimensional Printed Biomimetic Titanium Alloy Implants

Tumor resection and treatment of trauma-related regional large bone defects have major challenges in the field of orthopedics. Scaffolds that treat bone defects are the focus of bone tissue engineering. 3D printing porous titanium alloy scaffolds, prepared via electron beam melting technology, possess customized structure and strength. The addition of a growth factor coating to the scaffold introduces a specific form of biological activation. Vascular endothelial growth factor (VEGF) is key to angiogenesis and osteogenesis in vivo. We designed a porous titanium alloy scaffold/thermosensitive collagen hydrogel system, equipped with VEGF, to promote local osseointegration and angiogenesis. We also verified the VEGF release via thermosensitive collagen and proliferation and induction of the human umbilical vein endothelial cells (HUVECs) via the composite system in vitro. In vivo, using microscopic computed tomography (Micro-CT), histology, and immunohistochemistry analysis, we confirmed that the composite scaffold aids in angiogenesis-mediated bone regeneration, and promotes significantly more bone integration. We also discovered that the composite scaffold has excellent biocompatibility, provides bioactive VEGF for angiogenesis and osteointegration, and provides an important theoretical basis for the restoration of local blood supply and strengthening of bone integration.

AdipoRon Promotes the Osseointegration of Dental Implants in Mice With Type 2 Diabetes Mellitus

AdipoRon is an oral active synthetic small molecule with biological functions similar to adiponectin (APN). It is an APN receptor agonist that can improve insulin resistance and glucose intolerance. However, the role of AdipoRon in bone metabolism and related molecular mechanisms remains to be investigated. To explore the effect of AdipoRon on bone absorption and bone integration of type 2 diabetes mellitus (T2DM) mice with implants, we established surgery-induced model of osseointegration of dental implantation in T2DM mice of C57BL/6 db/db and normal mice homologous to diabetic mice. Micro-CT was used to analyze the femurs with the implant in the mice to detect the bone mass, H&E, and tartrate-resistant acid phosphatase (TRAP), and Safranin O-fast green staining was performed to analyze the bone formation and bone resorption. Bone integration-related markers as Rankl, bone morphogenetic protein 2 (BMP2), osteoprotegerin (OPG), osteopontin (OPN), and runt-related transcription factor 2 (Runx2) were also measured using immunohistochemistry. Our results indicated that diabetic mice showed a lower bone mass and decreased the osteoblast differentiation. AdipoRon attenuated diabetes-impaired bone volume (BV)/total volume (TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), and bone integration-related markers variation and promoted bone hyperplasia as well as repressed the osteoclast formation, especially in diabetic mice. AdipoRon may improve the osseointegration of dental implants in mice with T2DM by promoting osteogenesis and inhibiting bone resorption, and AdipoRon may serve as a promising oral strategy to improve the osseointegration ability of patients with diabetes.

Fabrication and Use of a Customized Provisional Composite Abutment in Dental Practice

Introduction. Reducing the time of implant integration and the period of prosthetics is an important task of dentistry since this leads to improved quality of life and successful rehabilitation of the patient. Therefore, currently, there is an intensely increased interest in immediate or early loading of the implant, when certain parameters of primary implant stability in the bone tissue are achieved. Materials and Methods. The materials used to perform the procedure for placement of a customized provisional composite abutment were a provisional prefabricated abutment with a retention grip for the composite; aluminum oxide powder with a particle size of 27 μm for better adhesion of the composite, with which the retention grip of the provisional abutment is coated; 3M Single Bond Universal light-curing adhesive applied to the provisional abutment; and Filtek Bulk Fill 3M composite including a low-viscosity radiopaque nanocomponent and ytterbium trifluoride filler with a particle size of 0.01–3.5 nm. Methods used in this study were as follows: fabrication technique using the Cervico system for a customized provisional composite abutment; sandblasting of the provisional abutment using the apparatus RONDOFLEX (KERR); light polymerization of low-viscosity composite using Demi Ultra Kerr lamp (luminous flux power not less than 1100 mW/cm2); and radiographic control of the abutment fit in the implant. Results. The surgical and orthopedic treatment of 20 patients was performed using this technique. The control group consisted of 11 patients with similar pathology, in whose surgery the fabrication of a provisional prosthesis was used. As a result, it was possible to form a gingival profile, in comparison with the control group, to accelerate mucogingival and bone integration, as well as to quickly carry out orthopedic rehabilitation of the patient. The average value of the time required for the final formation of soft tissues for prosthetics in patients in the experimental group was significantly lower than those in the comparison group ( p = 0.007 and p = 0.028 , respectively). In most clinical cases, there is no need for surgery on soft tissues, which eliminates the possibility of additional traumas. Conclusions. The use of a promising technology for the fabrication of a crown on the implant and a customized provisional composite abutment significantly reduced the period of orthopedic rehabilitation of the patient. Immediate implantation with a customized provisional composite abutment completely forms the gingival profile, reduces the risk of microbial contamination in the area of bone formation, minimizes soft tissue ischemia, and accelerates the processes of mucogingival and bone integration around the implant.

Biomimetic Zirconia with Cactus-Inspired Meso-Scale Spikes and Nano-Trabeculae for Enhanced Bone Integration

Biomimetic design provides novel opportunities for enhancing and functionalizing biomaterials. Here we created a zirconia surface with cactus-inspired meso-scale spikes and bone-inspired nano-scale trabecular architecture and examined its biological activity in bone generation and integration. Crisscrossing laser etching successfully engraved 60 μm wide, cactus-inspired spikes on yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) with 200–300 nm trabecular bone-inspired interwoven structures on the entire surface. The height of the spikes was varied from 20 to 80 μm for optimization. Average roughness (Sa) increased from 0.10 μm (polished smooth surface) to 18.14 μm (80 μm-high spikes), while the surface area increased by up to 4.43 times. The measured dimensions of the spikes almost perfectly correlated with their estimated dimensions (R2 = 0.998). The dimensional error of forming the architecture was 1% as a coefficient of variation. Bone marrow-derived osteoblasts were cultured on a polished surface and on meso- and nano-scale hybrid textured surfaces with different spike heights. The osteoblastic differentiation was significantly promoted on the hybrid-textured surfaces compared with the polished surface, and among them the hybrid-textured surface with 40 μm-high spikes showed unparalleled performance. In vivo bone-implant integration also peaked when the hybrid-textured surface had 40 μm-high spikes. The relationships between the spike height and measures of osteoblast differentiation and the strength of bone and implant integration were non-linear. The controllable creation of meso- and nano-scale hybrid biomimetic surfaces established in this study may provide a novel technological platform and design strategy for future development of biomaterial surfaces to improve bone integration and regeneration.

Bone Mesenchymal Stem Cells Contribute to Ligament Regeneration and Graft–Bone Healing after Anterior Cruciate Ligament Reconstruction with Silk–Collagen Scaffold

Anterior cruciate ligament (ACL) reconstruction was realized using a combination of bone mesenchymal stem cells (BMSCs) and silk–collagen scaffold, and an in vivo evaluation of this combination was performed. By combining type I collagen and degummed silk fibroin mesh, silk–collagen scaffolds were prepared to simulate ligament components. BMSCs isolated from bone marrow of rabbits were cultured for a homogenous population and seeded on the silk–collagen scaffold. In the scaffold and BMSC (S/C) group, scaffolds were seeded with BMSCs for 72 h and then rolled and used to replace the ACL in 20 rabbits. In the scaffold (S) group, scaffolds immersed only in culture medium for 72 h were used for ACL reconstruction. Specimens were collected at 4 and 16 weeks postoperatively to assess ligament regeneration and bone integration. HE and immunohistochemical staining (IHC) were performed to assess ligament regeneration in the knee cavity. To assess bone integration at the graft–bone interface, HE, Russell–Movat staining, micro-CT, and biomechanical tests were performed. After 4 weeks, vigorous cell proliferation was observed in the core part of the scaffold in the S/C group, and a quantity of fibroblast-like cells and extracellular matrix (ECM) was observed in the center part of the graft at 16 weeks after surgery. At 4 and 16 weeks postoperatively, the tenascin-C expression in the S/C group was considerably higher than that in the S group (4 w, p < 0.01 ; 16 w, p < 0.01 ). Furthermore, bone integration was better in the S/C group than in the S group, with histological observation of trabecular bone growth into the graft and more mineralized tissue formation detected by micro-CT (4 w, bone volume fraction (BV/TV), p = 0.0169 , bone mineral density (BMD), p = 0.0001 ; 16 w, BV/TV, p = 0.1233 , BMD, p = 0.0494 ). These results indicate that BMSCs promote ligament regeneration in the knee cavity and bone integration at the graft–bone interface. Silk–collagen scaffolds and BMSCs will likely be combined for clinical practice in the future.