Membranas de hidrogel / Hydrogel membranes

Este trabalho, partindo do tema elaborado, levantou o seguinte problema: As propriedades e vantagens estudadas nas membranas de Hidrogel, se faz desse material eficaz no tratamento dos tecidos periodontais na doença periodontal. Sendo assim, o objetivo deste trabalho foi realizar um levantamento bibliográfico sobre as propriedades e vantagens do uso de membranas de Hidrogel na Regeneração Óssea Guiada nos casos da perda óssea e a recessão gengival associada à Doença Periodontal. O uso de membrana para Regeneração Óssea Guiada (ROG) é um componente essencial do tratamento de doenças periodontais e na regeneração óssea. Neste caso, discutiremos as propriedades dos hidrogéis e seus benefícios e limitações nessa área. Apesar dos desafios significativos existentes, a regeneração óssea baseada em hidrogel é uma grande promessa para o futuro tratamento de doenças e defeitos relacionados aos ossos. Com uma compreensão aprofundada os hidrogéis serão, sem dúvida, uma ferramenta poderosa para o tratamento clínico de defeitos ósseos no futuro.

This study, based on the topic elaborated, raised the following problem: The properties and advantages studied in Hydrogel membranes and if this material can be effective in the treatment of periodontal tissues in periodontal disease. The objective of this work was to perform a bibliographic survey on the properties and advantages of using Hydrogel membranes in Guided Bone Regeneration in cases of bone loss and gingival recession associated with Periodontal Disease. The use of Guided Bone Regeneration (GBR) membrane is an essential component of the treatment of periodontal diseases and bone regeneration. In this case, we discussed the properties of hydrogels and their benefits and limitations in this area. Despite significant challenges, the hydrogel-based bone regeneration holds great promise for the future treatment of bone-related diseases and defects. With in-depth understanding, hydrogels will undoubtedly be a powerful tool for clinical treatment of bone defects in the future.

Enhancing osteoblast differentiation and bone repair: The priming effect of photobiomodulation on adipose stromal cells.

Cellular therapy using adipose tissue-derived mesenchymal stromal cells (at-MSCs) has garnered attention for the treatment of bone defects. Therefore, preconditioning strategies to enhance the osteogenic potential of at-MSCs could optimize cell therapy outcomes, and photobiomodulation (PBM) therapy has emerged as an effective, noninvasive, and low-cost alternative. This study explored the impacts of PBM on at-MSCs differentiation and the subsequent repair of bone defects treated with cell injection. Rat at-MSCs were cultured and irradiated (at-MSCsPBM) following the PBM protocol (660 nm; 20 mW; 0.714 W/cm2; 0.14 J; 5 J/cm2). Cellular differentiation was assessed based on the expression of gene and protein markers. Reactive oxygen species (ROS) were detected using fluorescence. At-MSCsPBM were injected into 5-mm calvarial lesions, and bone formation was analyzed using micro-CT and histological evaluations. At-MSCs were used as control. Data were analyzed using the ANOVA or t-test. At-MSCsPBM exhibited high levels of gene and protein runt-related transcription factor-2 (Runx2) and alkaline phosphatase (Alp) expression. PBM increased ALP activity and significantly reduced ROS levels. In addition, PBM increased the expression of Wnt pathway-associated genes. In vivo, there was an increase in the morphometric parameters, including bone volume, percentage of bone volume, bone surface area, and trabecular number, in at-MSCsPBM-treated defects compared with those in the control. These findings suggest that PBM enhances the osteogenic potential of at-MSCs, thereby supporting the advancement of improved cellular therapies for bone regeneration.

Effectiveness of the Association of Fibrin Scaffolds, Nanohydroxyapatite, and Photobiomodulation with Simultaneous Low-Level Red and Infrared Lasers in Bone Repair.

Biomaterials and biopharmaceuticals for correcting large bone defects are a potential area of translational science. A new bioproduct, purified from snake venom and fibrinogen from buffalo blood, aroused interest in the repair of venous ulcers. Expanding potential uses, it has also been used to form biocomplexes in combination with bone grafts, associated with physical therapies or used alone. The aim of this preclinical study was to evaluate low-level laser photobiomodulation (PBM) in critical defects in the calvaria of rats filled with nanohydroxyapatite (NH) associated with the heterologous fibrin biopolymer (HFB). Sixty animals were used, divided into six groups (n = 10 each): G1 (NH); G2 (HFB); G3 (NH + HFB); G4 (NH + PBM); G5 (HFB + PBM); G6 (NH + HFB + PBM). PBM simultaneously used red (R) and infrared (IR) light emission, applied intraoperatively and twice a week, until the end of the experiment at 42 days. Microtomography, bone formation can be seen initially at the margins of the defect, more evident in G5. Microscopically, bone formation demonstrated immature and disorganized trabeculation at 14 days, with remnants of grafting materials. At 42 days, the percentage of new bone formed was higher in all groups, especially in G5 (HFB, 45.4 ± 3.82), with collagen fibers at a higher degree of maturation and yellowish-green color in the birefringence analysis with Picrosirius-red. Therefore, it is concluded that the HFB + PBM combination showed greater effectiveness in the repair process and presents potential for future clinical studies.

Systemic ozone therapy as an adjunctive treatment in guided bone regeneration: a histomorphometrical and immunohistochemical study in rats.

OBJECTIVES: To assess the effectiveness of ozone therapy in guided bone regeneration (GBR) for critical size calvarial defects in rats. MATERIALS AND METHODS: 96 male Wistar rats were divided into four groups (n = 6 each). An 8 mm critical defect was created in the calvaria of each rat. The groups were: BIO (porcine collagen membrane, BioGide®), BIO + OZ (membrane with systemic ozone therapy every 2 days), COA + OZ (blood clot with ozone therapy), and COA (blood clot only). Evaluations at 7, 15, 30, and 60 days included histological, histomorphometric, inflammatory profile, Micro-CT, and immunohistochemical analyses. Statistical analysis involved two-factor ANOVA with Tukey's post-hoc test for general data, and one-factor ANOVA with Holm-Sidak post-hoc test for Micro-CT data. RESULTS: The BIO + OZ group demonstrated superior bone regeneration with well-organized, mature bone tissue and significant bone formation at 30 and 60 days. The COA + OZ group showed early angiogenesis and reduced inflammation, resulting in complete defect closure by 30 days. The BIO group had good regeneration, but less mature tissue compared to BIO + OZ. The COA group exhibited limited bone formation and higher porosity. CONCLUSION: Ozone therapy positively influences bone regeneration by enhancing cell proliferation and the healing response. CLINICAL RELEVANCE: Improving regenerative processes with auxiliary therapies like ozone therapy can be significant for advancing dental reconstructions.

Synthetic Bone Blocks Produced by Additive Manufacturing in the Repair of Critical Bone Defects.

This study evaluated the efficacy of synthetic bone blocks, composed of hydroxyapatite (HA) or ß-tricalcium phosphate (B-TCP), which were produced by additive manufacturing and used for the repair of critical size bone defects (CSDs) in rat calvaria. Sixty rats were divided into five groups (n = 12): blood clot (CONTROL), 3D-printed HA (HA), 3D-printed ß-TCP (B-TCP), 3D-printed HA + autologous micrograft (HA+RIG), and 3D-printed ß-TCP + autologous micrograft (B-TCP+RIG). CSDs were surgically created in the parietal bone and treated with the respective biomaterials. The animals were euthanized at 30 and 60 days postsurgery for microcomputed tomography (micro-CT) histomorphometric, and immunohistochemical analysis to assess new bone formation. Micro-CT analysis showed that both biomaterials were incorporated into the animals' calvaria. The HA+RIG group, especially at 60 days, exhibited a significant increase in bone formation compared with the control. The use of 3D-printed bioceramics resulted in thinner trabeculae but a higher number of trabeculae compared with the control. Histomorphometric analysis showed bone islands in close contact with the B-TCP and HA blocks at 30 days. The HA blocks (HA and HA+RIG groups) showed statistically higher new bone formation values with further improvement when autologous micrografts were included. Immunohistochemical analysis showed the expression of bone repair proteins. At 30 days, the HA+RIG group had moderate Osteopontin (OPN) staining, indicating that the repair process had started, whereas other groups showed no staining. At 60 days, the HA+RIG group showed slight staining, similar to that of the control. Osteocalcin (OCN) staining, indicating osteoblastic activity, showed moderate expression in the HA and HA+RIG groups at 30 days, with slight expression in the B-TCP and B-TCP+RIG groups. The combination of HA blocks with autologous micrografts significantly enhanced bone repair, suggesting that the presence of progenitor cells and growth factors in the micrografts contributed to the improved outcomes. It was concluded that 3D-printed bone substitute blocks, associated with autologous micrografts, are highly effective in promoting bone repair in CSDs in rat calvaria.

Histomorphometric Study of Non-critical Bone Defect Repair after Implantation of Magnesium-substituted Hydroxyapatite Microspheres.

Objective The present study aims to analyze histomorphometrically the repair of a non-critical bone defect after implantation of hydroxyapatite (HA) microspheres substituted by magnesium (Mg). Methods Thirty rats were distributed into 3 experimental groups, evaluated at 15 and 45 days postoperatively: HAG (bone defect filled with HA microspheres); HAMgG (bone defect filled with HA microspheres replaced with 1 mol% Mg), and CG (bone defect without implantation of biomaterials). Results After 15 days, the biomaterials filled the entire defect extent, forming a new osteoid matrix between the microspheres. In the CG, this neoformation was restricted to the edges with the deposition of loose connective tissue with reduced thickness. At 45 days, new bone formation filled almost the entire extension of the bone defect in the 3 groups, with statistically significant osteoid deposition in the CG despite the reduced thickness compared with the HAG and HAMgG. The groups with biomaterial implantation displayed a more abundant osteoid matrix than at 15 days. Conclusion The biomaterials studied showed biocompatibility, osteoconductivity, and bioactivity. The Mg concentration in the substituted HA did not stimulate more significant bone formation than HA without this ion.

Comparison of Bone Graft Preparations to Treat a Critical Bone Defect on a Rodent Animal Model.

Objective Although autologous bone grafting is the most widely used treatment for bone defects, the most effective preparation remains unclear. This animal study aimed to compare different autologous bone grafting preparation for the treatment of rat́s calvaria critical bone defect. Methods 122 rats were randomly allocated into three groups: Simulado, Macerated and Chopped. The specimens underwent craniotomies at the top center of their calvarias with a 7mm diameter circumferential cutter drill. The critical bone defect produced was treated or not according to the group the specimen wasallocated. The rats were euthanized at 3, 6 or 12 weeks post-op and its calvarias were analyzed by histomorphometry, bone densitometry, nanocomputed tomography (nCT), and biomechanical tests. Results The histomorphometry analysis showed the highest percentage of fulfillment of the critical bone defect in the chopped and macerated group when compared to simulado. The densitometry assessment evidenced higher bone mass at all endpoints analysis (p < 0.05) in the chopped group. The nCT data exhibited an expressive increase of bone in the chopped group when compared with the simulado and macerated groups. The biomechanical tests exhibited highest values of deformation, maximum force, and relative stiffness in the chopped group at any time of euthanasia (p < 0.05). Conclusions Our experimental work showed that chopped bone grafting preparation exhibited significant better outcomes than macerated in the treatment of a critical bone defect in rat́s calvaria.

Use of autologous micrografts associated with xenogeneic anorganic bone in vertical bone augmentation procedures with Barbell Technique®.

INTRODUCTION: Bidirectional vertical ridge augmentation in the posterior maxilla is very challenging. PURPOSE: To evaluate the regenerative potential of micrografts, derived from periosteum or bone tissue, added to an anorganic xenograft in vertical reconstruction of the posterior maxilla, by a prospective, controlled study. MATERIALS AND METHODS: After clinical selection and the analysis of CBCT scans, 24 posterior maxillary sites, in 19 patients, were treated by using Barbell Technique®. Sites requiring both inlay and onlay reconstruction were enrolled in the study. In the Control Group (CG, n = 8), a xenograft was used in the inlay site and for the onlay site, a 1:1 mix of xenograft and an autograft was used. In Test Group 1 (TG1, n = 8), both inlay and onlay sites were grafted with the xenograft associated with the micrografts derived from periosteum. In Test Group 2 (TG2, n = 8), both inlay and onlay sites were grafted with the xenograft associated with the micrografts derived from bone. Six months after the procedures, CBCT scans were obtained, and bone biopsy samples were harvested during implant placement surgery. The bone specimens were analyzed histomorphometrically, by measuring the percentages of vital mineralized tissue (VMT), non vital mineralized tissue (NVMT) and non mineralized tissue (NMT). Immunohistochemically, the levels of VEGF were categorized by a score approach. RESULTS: Histomorphometric analysis revealed, for the inlay grafts, no significant difference among the groups for VMT, NVMT and NMT. However, for onlay grafts, CG achieved a higher amount of VMT in comparison with TG2, and the opposite occurred for NMT values. In this regard, no statistical difference was observed between CG and TG1. Concerning immunohistochemistry, the VEGF values for CG and TG1 were slightly higher than those obtained by TG2 for both inlay and onlay grafts, but without statistical significance. CBCT analysis showed a similar level of gain for all groups, for both inlay and onlay bone augmentation sites. Clinically, one implant (in CG) within a total of 50 implants installed, had early failure and was replaced after 3 months. All patients received implant supported prosthesis. CONCLUSION: This study indicated that the clinical use of micrograft derived from periosteum may have some potential to increase bone formation in onlay reconstructions, unlike the micrograft derived from bone tissue.

Interaction of high lipogenic states with titanium on osteogenesis.

As obesity rates continue to rise, the prevalence of metabolic dysfunction and alcohol-associated steatotic liver disease (MetALD), a new term for Nonalcoholic Fatty Liver Disease (NAFLD), also increases. In an aging population, it is crucial to understand the interplay between metabolic disorders, such as MetALD, and bone health. This understanding becomes particularly significant in the context of implant osseointegration. This study introduces an in vitro model simulating high lipogenesis through the use of human Mesenchymal Stroma Cells-derived adipocytes, 3D intrahepatic cholangiocyte organoids (ICO), and Huh7 hepatocytes, to evaluate the endocrine influence on osteoblasts interacting with titanium. We observed a significant increase in intracellular fat accumulation in all three cell types, along with a corresponding elevation in metabolic gene expression compared to the control groups. Notably, osteoblasts undergoing mineralization in this high-lipogenesis environment also displayed lipid vesicle accumulation. The study further revealed that titanium surfaces modulate osteogenic gene expression and impact cell cycle progression, cell survival, and extracellular matrix remodeling under lipogenic conditions. These findings provide new insights into the challenges of implant integration in patients with obesity and MetALD, offering a deeper understanding of the metabolic influences on bone regeneration and implant success.

Tricalcium phosphate-loaded injectable hydrogel as a promising osteogenic and bactericidal teicoplanin-delivery system for osteomyelitis treatment: An in vitro and in vivo investigation.

Osteomyelitis is an inflammation of bone tissue usually caused by pyogenic bacteria. The most recurrent clinical approach consists of bone debridement followed by parenteral administration of antibiotics. However, systemic antibiotic treatment has limitations regarding absorption rate and bioavailability over time. The main challenge of osteomyelitis treatment consists of coupling the persistent infection treatment with the regeneration of the bone debrided. In this work, we developed an injectable drug delivery system based on poloxamer 407 hydrogel containing undoped Mg, Zn-doped tricalcium phosphate (ß-TCP), and teicoplanin, a broad-spectrum antibiotic. We evaluated how the addition of teicoplanin and ß-TCP affected the micellization, gelation, particle size, and surface charge of the hydrogel. Later, we studied the hydrogel degradation and drug delivery kinetics. Finally, the bactericidal, biocompatibility, and osteogenic properties were evaluated through in vitro studies and confirmed by in vivo Wistar rat models. Teicoplanin was found to be encapsulated in the corona portions of the hydrogel micelles, yielding a bigger hydrodynamics radius. The encapsulated teicoplanin showed a sustained release over the evaluated period, enough to trigger antibacterial properties against Gram-positive bacteria. Besides, the formulations were biocompatible and showed bone healing ability and osteogenic properties. Finally, in vivo studies confirmed that the proposed locally injected formulations yielded osteomyelitis treatment with superior outcomes than parenteral administration while promoting bone regeneration. In conclusion, the presented formulations are promising drug delivery systems for osteomyelitis treatment and deserve further technological improvements.

Bone Regeneration in the Anterior Maxilla With Titanium Mesh and Advanced-Platelet-Rich Fibrin: A Case Report With 2-Year Follow-up.

Guided bone regeneration involving the use of titanium mesh and platelet-rich fibrin could be a feasible approach in cases of severely atrophic ridges. The purpose of this case report was to present an esthetic and functional rehabilitation in the anterior maxilla with the installation of dental implants in conjunction with guided bone regeneration using titanium mesh and advanced platelet-rich fibrin (A-PRF). A 60-year-old patient presented bone atrophy and partial edentulism in the anterior maxilla. After clinical and cone beam computed tomography assessment, guided bone regeneration was planned using a titanium mesh and A-PRF with xenograft bone. After 8 months of healing, the dental implants were placed with the aid of a surgical guide to obtain accurate 3-dimensional positioning. Prosthetic rehabilitation was carried out with individualized crowns. After 2 years of follow-up, radiographic analysis demonstrated a good quality and density of the bone tissue adjacent to the dental implants. No radiolucent areas were observed, and there were no clinical signs of failure. In cases of severe atrophy, using a titanium mesh and A-PRF proved to be a feasible alternative for bone reconstruction prior to dental implant placement. This approach can aid dental professionals in achieving an ideal implant positioning for rehabilitation with individualized crowns.

CCKR signaling map, G-Protein bindings, hormonal regulation, and neural mechanisms may influence the osteogenic/cementogenic differentiation potential of hPDLSCs.

OBJECTIVE: Periodontal regeneration poses challenges due to the periodontium's complexity, relying on mesenchymal cells from the periodontal ligament (hPDLSCs) to regenerate hard tissues like bone and cementum. While some hPDLSCs have high regeneration potential (HOP-hPDLSCs), most are low potential (LOP-hPDLSCs). This study analyzed hPDLSCs from a single donor to minimize inter-individual variability and focus on key differences in differentiation potentials. DESIGN: This study used RNA-seq, genomic databases, and bioinformatics tools to explore signaling pathways (SPs), biological processes (BPs), and molecular functions (MFs) guiding HOP cells to mineralized matrix production. It also investigated limitations of LOP cells and strategies for enhancing their osteo/cementogenesis. RESULTS: In basal conditions, HOP exhibited a multifunctional gene network with higher expression of genes related to osteo/cementogenesis, cell differentiation, immune modulation, stress response, and hormonal regulation. In contrast, LOP focused on steroid hormone biosynthesis and nucleic acid maintenance. During osteo/cementogenic induction, HOP showed strong modulation of genes related to angiogenesis, cell division, mesenchymal differentiation, and extracellular matrix production. LOP demonstrated neural synaptic-related processes and preserved cellular cytoskeleton integrity. CCKR map signaling and G-protein receptor bindings gained significance during osteo/cementogenesis in HOP-hPDLSCs. Both HOP and LOP shared common BPs related to gastrointestinal and reproductive system development. CONCLUSION: The osteo/cementogenic differentiation of HOP cells may be regulated by CCKR signaling, G-protein bindings, and specific hormonal regulation. LOP cells seem committed to neural mechanisms. This study sheds light on hPDLSCs' complex characteristics, offering a deeper understanding of their differentiation potential for future periodontal regeneration research and therapies.

Carbon fiber felt scaffold from Brazilian textile PAN fiber for regeneration of critical size bone defects in rats: A histomorphometric and microCT study.

The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty-four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty-four animals were randomly divided into four groups: control (C)-bone defect + blood clot, non-activated carbon fiber felt (NACFF)-bone defect + NACFF, activated carbon fiber felt (ACFF)-bone defect + ACFF, and silver activated carbon fiber felt (Ag-ACFF)-bone defect + Ag-ACFF, and was observed by 15 and 60 days for histomorphometric, three-dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration.

Exéresis de quiste nasopalatino y regeneración ósea / Excisão de cistos nasopalatinos e regeneração óssea / Nasopalatine cyst excision and bone regeneration

Introducción: El quiste nasopalatino es un quiste no odontogénico, ubicado dentro del conducto nasopalatino del maxilar, su diagnóstico en la mayoría de los casos es por hallazgo radiológico de rutina y en otros casos por la presencia de sintomatología; llegando a generar dolor, parestesia y signos visibles como deformaciones faciales. Descripción del caso: El objetivo de este artículo es la revisión de la literatura y presentación del caso de un paciente masculino de 38 años de edad, que acude a la consulta por presentar aumento de volumen en la maxila anterior, de dos años de evolución que presentó resultados favorables luego de la exéresis y colocación de injerto óseo. Consideraciones finales: El quiste nasopalatino representa menos del 5% de los quistes a nivel maxilar y su recurrencia es baja. Cuando se trata de un quiste de gran tamaño con destrucción del tejido óseo circundante, la mejor opción es la utilización de un injerto óseo dependiendo tanto de la biocompatibilidad, del sitio afectado y de los costos. Se considera como gold standard a la matriz ósea desmineralizada (DBX) debido a su capacidad de osteoinducción, osteoconducción y osteogénesis... (AU)

Introdução: O cisto nasopalatino é um cisto não odontogênico, localizado no interior do ducto nasopalatino da maxila, a lesao é descoberta na maior parte dos casos como um achado radiológico de rotina e em outros casos pela presença de sintomatologia; incluindo dor, parestesias e deformidades faciais. Descrição do caso: O objetivo deste artigo é revisar a literatura e apresentar o caso de um paciente masculino de 38 anos de idade que veio à clínica com um aumento volumétrico da região anterior da maxila, com uma evolução de dois anos, que apresentou resultados favoráveis após excisão e colocação de enxerto ósseo. Considerações finais: O cisto nasopalatino representa menos de 5% dos cistos maxilares e a recorrência é baixa. Quando se trata de uma grande lesão com destruição do tecido ósseo circundante, a melhor opção é a utilização de um enxerto ósseo dependendo da biocompatibilidade, do local afetado e dos custos. A matriz óssea desmineralizada (DBX) é considerado o material padrão para a reconstrução óssea da região afetada devido à sua capacidade de osteoindução, osteocondução e osteogénese... (AU)

Introduction: The nasopalatine cyst is a non-odontogenic cyst, located within the nasopalatine duct of the maxilla, its diagnosis in most cases is by routine radiological finding and in other cases by the presence of symptomatology; coming to generate pain, paresthesia and visible signs such as facial deformities. Case description: The objective of this article is to make a literature review and presentation of the case of a 38-year-old male patient, who comes to the consultation for presenting an increase in volume in the anterior maxilla, of two years of evolution that presented favorable results after excision and placement of bone graft. Final considerations: Nasopalatine cyst represents less than 5% of the cysts at maxillary level and its recurrence is low. When it is a large cyst with destruction of the surrounding bone tissue, the best option is the use of a bone graft depending on biocompatibility, the affected site and costs. Demineralized bone matrix (DBX) is considered the gold standard due to its capacity for osteoinduction, osteoconduction and osteogenesis... (AU)

Bone Incorporation of a Poly (L-Lactide-Co-D, L-Lactide) Internal Fixation Device in a Rat's Tibia: Microtomographic, Confocal LASER, and Histomorphometric Analysis.

This study evaluated the bone incorporation process of a screw-shaped internal fixation device made of poly (L-lactide-co-D, L-lactide) (PLDLLA). Thirty-two male Wistar rats received 32 fixation devices (2 mm × 6 mm) randomly assigned to either the right or left tibia and one implant in each animal. After 7, 14, 28, and 42 days, the rats were euthanized and the specimens were subjected to microtomographic computed tomography (microCT) and histomorphometric analyses to evaluate bone interface contact (BIC%) and new bone formation (NBF%) in cortical and cancellous bone areas. The animals euthanized on days 28 and 42 were treated with calcein and alizarin red, and confocal LASER microscopy was performed to determine the mineral apposition rate (MAR). Micro-CT revealed a higher percentage of bone volume (p < 0.006), trabecular separation (p < 0.001), and BIC in the cortical (p < 0.001) and cancellous (p = 0.003) areas at 28 and 42 days than at 7 and 14 days. The cortical NBF at 42 days was greater than that at 7 and 14 days (p = 0.022). No statistically significant differences were observed in cancellous NBF or MAR at 28 and 42 days. Based on these results, it can be seen that the PLDLLA internal fixation device is biocompatible and allows new bone formation around the screw thread.

Inflammatory Profile of Different Absorbable Membranes Used for Bone Regeneration: An In Vivo Study.

BACKGROUND: Guided bone regeneration (GBR) has become a necessary practice in implantology. Absorbable membranes have shown advantages over non-absorbable membranes, such as blood support of bone tissue. This study aimed to evaluate five collagen membranes in rat calvaria critical-size defects through a histomorphometric analysis of the inflammatory profile during the initial phase of bone repair. MATERIALS AND METHODS: A total of 72 Albinus Wistar rats were used for the study, divided into six groups, with 12 animals per group, and two experimental periods, 7 and 15 days. The groups were as follows: the CG (clot), BG (Bio-Gide®), JS (Jason®), CS (Collprotect®), GD (GemDerm®), and GDF (GemDerm Flex®). RESULTS: Data showed that the BG group demonstrated an inflammatory profile with an ideal number of inflammatory cells and blood vessels, indicating a statistically significant difference between the JS and CS groups and the BG group in terms of the number of inflammatory cells and a statistically significant difference between the JS and CS groups and the GD group in terms of angiogenesis (p < 0.05). CONCLUSIONS: We conclude that different origins and ways of obtaining them, as well as the thickness of the membrane, can interfere with the biological response of the material.

A Novel Device for the Evaluation of In Vitro Bacterial Colonization in Membranes for Guided Tissue and Bone Regeneration.

Purpose: To evaluate, in vitro, the efficiency of a novel apparatus to test the adherence and penetration of bacteria on different membranes for guided regeneration. Methodology: To create the 3D device, Computer Aided Design/Computer Aided Manufacturing (CAD/CAM) systems were used. Three types of biomaterials were tested (n = 6): (DT) a collagen membrane; (DS) a polymer membrane; and (LP) a dense polytetrafluoroethylene barrier. The biomaterials were adapted to the apparatuses and challenged with two different monospecies bacterial culture of A. actinomycetemcomitans b and S. mutans. After 2 h, bacterial adherence and penetration were quantified by counting the number of colony-forming units (CFUs). Two specimens from each group were used for image analysis using Confocal Laser Scanning Microscopy. Statistical analysis was performed. Findings: The DS group had a higher adherence of S. mutans compared to A. actinomycetemcomitans b (p = 0.05). There was less adherence of A. actinomycetemcomitans b in the DS group, compared to the LP (p = 0.011) and DT (p < 0.001) groups. Only the membranes allowed penetration, which was blocked by barriers. The DT group allowed a greater penetration of S. mutans to occur compared to A. actinomycetemcomitans b (p = 0.009), which showed a higher penetration into the DS membranes compared to S. mutans (p = 0.016). The penetration of A. actinomycetemcomitans b through DS was higher compared to its penetration through DT and LP (p < 0.01 for both). DT and DS allowed a greater penetration of S. mutans to occur compared to LP, which prevented both bacterial species from penetrating. Conclusion: The apparatus allowed for the settlement and complete sealing of the biomaterials, enabling standardization.

The Addition of Hydroxyapatite Nanoparticles on Implant Surfaces Modified by Zirconia Blasting and Acid Etching to Enhance Peri-Implant Bone Healing.

This study investigated the impact of adding hydroxyapatite nanoparticles to implant surfaces treated with zirconia blasting and acid etching (ZiHa), focusing on structural changes and bone healing parameters in low-density bone sites. The topographical characterization of titanium discs with a ZiHa surface and a commercially modified zirconia-blasted and acid-etched surface (Zi) was performed using scanning electron microscopy, profilometry, and surface-free energy. For the in vivo assessment, 22 female rats were ovariectomized and kept for 90 days, after which one implant from each group was randomly placed in each tibial metaphysis of the animals. Histological and immunohistochemical analyses were performed at 14 and 28 days postoperatively (decalcified lab processing), reverse torque testing was performed at 28 days, and histometry from calcified lab processing was performed at 60 days The group ZiHa promoted changes in surface morphology, forming evenly distributed pores. For bone healing, ZiHa showed a greater reverse torque, newly formed bone area, and bone/implant contact values compared to group Zi (p < 0.05; t-test). Qualitative histological and immunohistochemical analyses showed higher features of bone maturation for ZiHa on days 14 and 28. This preclinical study demonstrated that adding hydroxyapatite to zirconia-blasted and acid-etched surfaces enhanced peri-implant bone healing in ovariectomized rats. These findings support the potential for improving osseointegration of dental implants, especially in patients with compromised bone metabolism.

The efficacy of Platelet and Leukocyte Rich Fibrin (L-PRF) in the healing process and bone repair in oral and maxillofacial surgeries: a systematic review.

INTRODUCTION: The search to optimize the healing and bone repair processes in oral and maxillofacial surgeries reflects the constant evolution in clinical practice, driven by the demand for increasingly satisfactory results and the need to minimize postoperative complications. OBJECTIVE: To evaluate the efficacy of Platelet and Leukocyte Rich Fibrin (L-PRF) in the healing and bone repair process in oral and maxillofacial surgeries. MATERIALS AND METHODS: The systematic review protocol for this study included the definition of the research question, the domain of the study, the databases searched, the search strategy, the inclusion and exclusion criteria, the types of studies to be included, the measures of effect, the methods for screening, data extraction and analysis, and the approach to data synthesis. Systematic literature searches were carried out on Cochrane databases, Web of Science, PubMed, ScienceDirect, Embase and Google Scholar. RESULTS: The strategic search in the databases identified 1,159 studies. After removing the duplicates with the Rayyan© software, 946 articles remained. Of these, 30 met the inclusion criteria. After careful evaluation based on the inclusion and exclusion criteria, 8 studies were considered highly relevant and included in the systematic review. CONCLUSION: Platelet and Leukocyte Rich Fibrin (L-PRF) has a positive effect on the healing process and bone repair in oral and maxillofacial surgeries.

Utilization of Additive Manufacturing Techniques for the Development of a Novel Scaffolds with Magnetic Properties for Potential Application in Enhanced Bone Regeneration.

This study focuses on designing and evaluating scaffolds with essential properties for bone regeneration, such as biocompatibility, macroporous geometry, mechanical strength, and magnetic responsiveness. The scaffolds are made using 3D printing with acrylic resin and iron oxides synthesized through solution combustion. Utilizing triply periodic minimal surfaces (TPMS) geometry and mask stereolithography (MSLA) printing, the scaffolds achieve precise geometrical features. The mechanical properties are enhanced through resin curing, and magnetite particles from synthesized nanoparticles and alluvial magnetite are added for magnetic properties. The scaffolds show a balance between stiffness, porosity, and magnetic responsiveness, with maximum compression strength between 4.8 and 9.2 MPa and Young's modulus between 58 and 174 MPa. Magnetic properties such as magnetic coercivity, remanence, and saturation are measured, with the best results from scaffolds containing synthetic iron oxides at 1% weight. The viscosity of the mixtures used for printing is between 350 and 380 mPas, and contact angles between 90° and 110° are achieved. Biocompatibility tests indicate the potential for clinical trials, though further research is needed to understand the impact of magnetic properties on cellular interactions and optimize scaffold design for specific applications. This integrated approach offers a promising avenue for the development of advanced materials capable of promoting enhanced bone regeneration.