Guided Bone Regeneration Research Articles

Opportunity of the Effect of Injectable Platelet Rich Fibrin (I-PRF) Mixed with Bone Graft on the Correlation Between Dental Implant Stability and Alveolar Ridge Width. A Clinical Comparative Study

The potential impact of injectable platelet-rich fibrin (I-PRF) combined with bone graft as a guided bone regeneration on the relationship between dental implant stability, alveolar ridge width, and dental implant dimension. Materials and methods: The present prospective comparative study was registered at ClinicalTrials.gov (ID number: NCT05427643). A total of 13 patients aged 18-65 years (11 females and 2 males) presented with missing teeth in either the maxilla or the mandible or both and met the eligibility criteria and enrolled in this study treated with 40 dental implants. These cases were allocated into two groups, control group in which the implants were placed without I-PRF and a study group (advanced cases with narrow alveolar ridge) in which implants were installed with I-PRF mixed with synthetic bone graft at the dehiscence sites around the implants. 22 (55%) dental implants were inserted in patients with alveolar bone width of ˂ 3.5 mm and 18 (45%) dental implants were inserted in ridge with ≥ 3.5 mm. The primary stability was measured at the time of surgery and Secondary stability was measured 24 weeks after dental implant installation with Anycheck device in implant stability test (IST) values. Results: Twenty dental implants were installed in each study group. According to the results obtained in this study, there was significant difference between primary stability (69.96±8.5 vs 74.50±4.3) of both groups and secondary stability (69.96±8.5 vs 76.32±6.5) values of group A with bone width of ≥ 3.5 mm and dental implant dimension 4.1 mm. Conclusion: The addition of I-PRF with bone graft for augmentation of dehiscence and fenestration peri-implant defects with simultaneous implant placement results in 100% survival rate with statistical differences in implant secondary stability between study groups. However, the results were clinically irrelevant.

Developing a multifunctional gradient pore structure Janus membrane loaded with MB@ZIF-8 nanoparticles and hydroxyapatite for guided periodontal bone regeneration

The guided tissue regeneration (GTR) procedure has become an important process for the treatment of periodontal tissue regeneration, using the membrane as a mechanical barrier to generate a distance across the defect that subsequently allowing bone regeneration. Due to the complexity of periodontal microenvironment caused by bacterial infections, inflammation, and fibrous tissue penetration, the guided tissue regeneration membrane is required to have antibacterial and barrier functions. We developed a loaded methylene blue @ ZIF-8 and hydroxyapatite gradient thermoplastic polyurethane Janus membrane for antibacterial osteogenic and barrier. This Janus membrane with a porous gradient structure was prepared to use phase-conversion method. The rough layer facilitated cell growth and promoted periodontal bone regeneration, whereas the smooth layer isolated the growing fiber tissue.The rapid release of reactive oxygen species in the early stage and continuous release of zinc ions by methylene blue @ZIF-8 can achieve long-term synergistic antibacterial effect, with antibacterial rates of 84 % and 72 % against Escherichia coli and Staphylococcus aureus, respectively, which can effectively reduce the local inflammation caused by bacteria. In summary, we applied the Janus membrane to a rat periodontal bone defect model, and the membrane showed good surgical performance, barrier properties, osteogenic properties, and antibacterial effects, which could have broad application prospects in the treatment of periodontal bone defects.

A Simplified GBR Treatment and Evaluation of Posterior Seibert Class I Ridge Defects via Bio-collagen and Platelet-Rich Fibrin: A Retrospective Study.

Classical guided bone regeneration (GBR) treatments can achieve favorable clinical results for ridge defects. However, extensive bone augmentation in the non-esthetic area in the posterior region for minor ridge defects is unnecessary. Therefore, this study used a collagen and Platelet-rich fibrin (PRF) mixture for bone augmentation on minor posterior ridge defects and evaluated the effects. 22 Seibert Class I ridge defects were treated with BC and covered with a PRF membrane (simplified guided bone regeneration, simplified GBR) and other 22 were treated with Bio-Oss and covered with Bio-Gide (classical GBR). Cone-beam computed tomography imaging was conducted 6months post-surgery to compare the ridge's horizontal width (HW) and buccal ridge's horizontal width to assess the osteogenic effect. In addition, the buccal ridge contour morphology was studied and classified. The buccal ridge contour of simplified GBR was Type A in 14 cases, Type B in 7 cases, and Type C in 1 case and it of classical GBR was Type A in 11 cases, Type B in 8 cases, and Type C in 3 cases. The mean HW significantly increased by 1.50mm of simplified GBR treatment, while it increased by 1.83mm in classical GBR treatment. The combined use of BC and PRF had a significant effect on bone augmentation and this treatment exhibited promising clinical results for correcting posterior Seibert Class I ridge defects. The morphological classification of the reconstructive effect in this study can be utilized in future clinical work.

Alveolar Ridge Preservation Using a Novel Species-Specific Collagen-Enriched Deproteinized Bovine Bone Mineral: Histological Evaluation of a Prospective Case Series.

In recent years, the significance of maintaining the alveolar ridge following tooth extractions has markedly increased. Alveolar ridge preservation (ARP) is a commonly utilized technique and a variety of bone substitute materials and biologics are applied in different combinations. For this purpose, a histological evaluation and the clinical necessity of subsequent guided bone regeneration (GBR) in delayed implantations were investigated in a prospective case series after ARP with a novel deproteinized bovine bone material (95%) in combination with a species-specific collagen (5%) (C-DBBM). Notably, block-form bone substitutes without porcine collagen are limited, and moreover, the availability of histological data on this material remains limited. Ten patients, each scheduled for tooth extraction and desiring future implantation, were included in this study. Following tooth extraction, ARP was performed using a block form of C-DBBM in conjunction with a double-folded bovine cross-linked collagen membrane (xCM). This membrane was openly exposed to the oral cavity and secured using a crisscross suture. After a healing period ranging from 130 to 319 days, guided trephine drilling was performed for implant insertion utilizing static computer-aided implant surgery (s-CAIS). Cores harvested from the area previously treated with ARP were histologically processed and examined. Guided bone regeneration (GBR) was not necessary for any of the implantations. Histological examination revealed the development of a lattice of cancellous bone trabeculae through appositional membranous osteogenesis at various stages surrounding C-DBBM granules as well as larger spongy or compact ossicles with minimal remnants. The clinical follow-up period ranged from 2.5 to 4.5 years, during which no biological or technical complications occurred. Within the limitations of this prospective case series, it can be concluded that ARP using this novel C-DBBM in combination with a bovine xCM could be a treatment option to avoid the need for subsequent GBR in delayed implantations with the opportunity of a bovine species-specific biomaterial chain.

Effect of Different Graft Material Consistencies in the Treatment of Minimal Bone Dehiscence: A Retrospective Pilot Study.

Among different therapeutic strategies proposed in the case of bone volume deficit, guided bone regeneration (GBR) is a consolidated surgical procedure. The objective of this study is to retrospectively evaluate the behavior of two bone grafts with different consistencies in the GBR procedure by measuring the volumetric tissue changes 1 year after surgery. For this retrospective analysis, 25 cases of GBR with simultaneous implant insertion were selected. A total of 13 were grafted with a porcine cortico-cancellous bone mix (CCBM group), and 12 were grafted with a pre-hydrated granulated cortico-cancellous bone mix of porcine origin blended with 20% TSV gel (Collagenated-CCBM). A collagen membrane was fixed to cover the bone defect. A total of 42 implants were placed with computer-guided surgery. Preoperative and 12-month postoperative digital impressions were used to evaluate dimensional changes. Student's t-test used for independent samples showed no statistically significant differences between the integrated distance (p = 0.995) and mean distance (p = 0.734). The mean integrated distance in the CCBM group was 41.80 (SD. 101.18) compared to a mean of 42.04 (SD. 66.71) in the Collagenated-CCBM group. Given the limitations of this study, in patients with peri-implant bone dehiscence, simple heterologous and collagenated heterologous cortico-cancellous bone grafts are suitable for filling the bone defect to promote bone regeneration, although further studies are needed.

CBCT in Dental Implantology: A Key Tool for Preventing Peri-Implantitis and Enhancing Patient Outcomes.

(1) Introduction: Trust is a cornerstone of the patient-physician relationships. Unforeseen complications in the health care system could jeopardize patients' trust in their physicians. (2) Aim: This article presents a quantitative figure regarding foreseeing the necessity of a three-dimensional quantitative visualization of bone structure and concurrently preparing for an ancillary procedure by a dentist to successfully perform the surgery that could minimize unforeseen complications; (3) Materials and method: This retrospective study has been derived based on an analysis of 1134 patients who had received 4800 dental implants from January 2001 to August 2020, out of which 200 cases were randomly selected for this study. Each procedure during implant treatment was categorized as OPG (Orthopantomography) or OPG with CBCT as per all the procedures which included and were coded as follows, 1: Surgery & Restoration, 2: GBR (Guided Bone Regeneration), 3: GTR (Guided Tissue Regeneration), 4: Block Bone Graft, 5: Spreading, 6: Splitting, 7: Internal Sinus, 8: External Sinus, 9: PRF (Platelet Rich Fibrin). Any of the 200 cases in which implant placement could not have been performed for reasons related to a lack of CBCT were selected for this study. The surgery was aborted halfway through without implant placement in these cases due to a lack of bone quantity and/or lack of primary stability. These cases were registered for re-evaluation and statistical analysis; (4) Results: 7% of the cases that used OPG alone led the surgeon to unexpectedly abort in the middle of the surgery without implant placement. All (100%) of the patients who had CBCT during treatment planning were able to receive implants during the surgery. None of the patients left the surgery without receiving implants if CBCT was used (0%); (5) Discussion: Radiographic image quality is defined as the amount of information within the image that allows the radiologist to make a diagnostic decision with a particular level of certainty (Martin et al., 1999) and hence the importance of CBCT. The unexpected 7% of devastating situations for patients who started surgery but did not have implant placement led to [A] aborting the surgery, [B] procedural difficulties requiring an alternative treatment plan, [C] a negative impact on the patient's behavior, and [D] wanting to change doctor due to a lack of trust; (6) Conclusion: This study indicates that in implant dentistry patients' mistrust could be avoided by 7% if CBCT is obtained. It also shows the significance of cone-beam computed tomography as an adjunct to panoramic radiography during the diagnosis and treatment planning phase. The use of panoramic radiography alone can lead to a 7% likelihood of misdiagnosis. A lack of CBCT during treatment planning negatively affects the outcome of surgical procedures.

Modified approach of regenerative treatment for distal intrabony defect beneath non-keratinized mucosa at terminal molar: A case report

BACKGROUND Intrabony defects beneath non-keratinized mucosa are frequently observed at the distal site of terminal molars. Consequently, the application of regenerative treatment using the modified wedge-flap technique is considered impractical for these specific dental conditions. CASE SUMMARY This article proposes a modified surgical procedure aimed at exposing the distal intrabony defect by making a vertical incision in the keratinized buccal gingiva. The primary objective is to maintain gingival flap stability, thereby facilitating periodontal regeneration. The described technique was successfully employed in a case involving the left mandibular second molar, which presented with an intrabony defect without keratinized gingiva at the distal site. In this case, an incision was made on the disto-buccal gingival tissue, creating a tunnel-like separation of the distal non-keratinized soft tissue to expose the intrabony defect. Subsequently, bone grafting and guided tissue regeneration surgeries were performed, resulting in satisfactory bone fill at 9 mo postoperatively. CONCLUSION This technique offers a regenerative opportunity for the intrabony defects beneath non-keratinized mucosa and is recommended for further research.

Guided Bone Regeneration for the Treatment of Peri-Implantitis: Clinical Case Report

Periodontal disease is characterized as an inflammatory process that damages the periodontal lining and/or support tissues. Peri-implantitis is among the periodontal alterations, being caused by bacterial biofilm causing loss of underlying bone insertion, leading to modifications in its architecture that form intraosseous defects of various types. For the treatment of peri-implantitis there are non-surgical, surgical, resective, regenerative, combined techniques and the decision-making will depend on the degree of the bone defect. Therefore, guided bone regeneration (GBR) is an efficient and simple technique for bone augmentation, which is widely used to restructure bone defects that occur in the alveolar ridge and in the peri-implant region. Biomaterials are alternatives to be used in guided bone regeneration due to their excellent biocompatibility, osteoinductive properties, low degradation rate and their hydrophilicity, which collaborates with the absorption of blood cells and proteins that will help in osseointegration. Female, 58-year-old normosistemic patient, attended a private dental office complaining of pain, bad smell, bleeding and bad taste in the peri-implant region referring to element 25, on its distal face to the mesial face of the element tooth 26. After imaging exams, periodontal probing and the patient's past history, extraction of element 26 was performed, decontamination protocol of the implant surface of 25 through mechanical, chemical and physical means performing antimicrobial photodynamic therapy and finally, a guided bone regeneration was performed, using the allogeneic bone grafting technique associated with a polytetrafluoroethylene membrane in its expanded form (e-PTFE) for recovery of the bone defect and alveolar preservation. Thus, guided bone regeneration has shown high success rates and greater predictability when well indicated and performed, making it important for the maintenance of periodontal and peri-implant health.

Mechanical Properties, biodegradable Behavior and biocompatibility of Zn-0.5Ti alloy membranes produced by powder metallurgy for Guided bone regeneration

The Zn-0.5Ti alloy bone regeneration membranes, prepared via powder metallurgy, hot extrusion, and hot rolling, exhibit robust mechanical properties (tensile strength: 122.5 ± 1.8 MPa, elongation: 18.3 ± 0.7 %), appropriate degradation rate (0.127 mm/year in SBF solution), and good biocompatibility (cytotoxicity grade 0–1). After 4 and 8 weeks of implantation, the alloy showed significant bone growth (bone volume ratios (BV/TV): 11.3 ± 1.8 % and 23.1 ± 3.5 %, respectively, measured by Micro-CT), indicating promising potential as a GBR membrane material.

Guided bone regeneration and implantological surgery in patients with a complicated alveolar dental trauma. A case report

Background: The difficulty of dental restoration varies depending on the factors that caused the loss or destruction of the original tissue, the major cause of dental rehabilitation is trauma fracture being more common in young people, these fractures can be restored or cause tooth extraction, in those cases where trauma causes tooth extraction various factors such as density and state of bone contour play an important role when what is wanted is a rehabilitation by dental implant, This is why different techniques and bone graft materials are combined with platelet-rich fibrin to increase the success rate.Objective: To show the clinical management of a patient with complicated alveolar trauma, exposing the surgical protocol, using two types of bone grafts and collagen membranes. Case Report: Fema- le patient comes to a consultation with a history of complicated dentoalveolar trauma 1 month before care, presents complicated coronal fracture of 12, 21 and 22, It was decided to perform surgical procedure with bone graft in combination with collagen membrane. Results: The patient developed favorably, obtaining the desired aesthetic and functional results. Conclusion: The application of guided bone regeneration treatment and implant surgery as performed in the reported case was a favorable and innovative option for oral rehabilitation. After 1 year of follow-up of the case, implant and peri-implant stability is evidenced in the use of two types of grafts.

Interrupted time series analysis of chronic periodontitis-related procedures before and after the scaling reimbursement policy in Korea.

To study the use of a quasi-experimental design to assess the effects of scaling reimbursement policies on the incidence of chronic-periodontitis procedures. Interrupted time series analysis was used to compare the effects before and after policy implementation using data on the number of periodontitis-related procedures from the Korean National Health Insurance Service-National Sample Cohort (n = 740,467) and the Health Screening Cohort (n = 337,904). Periodontitis-related procedures with diagnosis codes were categorized into basic (scaling or root planing), intermediate (subgingival curettage) and advanced (tooth extraction, periodontal flap surgery, bone grafting for alveolar bone defects or guided tissue regeneration). Subjects' demographics and comorbidities were considered. The incidence rate of immediate changes and gradual effects before and after policy implementation was assessed. Following the policy implementation from July 2013, an immediate increase was observed in total and basic procedures. No significant changes were noted in intermediate and advanced procedures initially. A decrease in the slope of intermediate procedures was observed in both databases. Advanced procedures showed varied trends, with no change in the National Sample Cohort but an increase in the Health Screening Cohort, particularly among subjects with comorbidities. Following the new policy implementation, the number of intermediate procedures decreased while the number of advanced procedures increased, especially among patients with comorbidities. These findings offer valuable insights on policy evaluation.

Effects of hard- and/or soft-tissue grafting with early implant placement: Histomorphometric outcomes of an exploratory study in canines.

To histomorphometrically determine the effects of hard- and/or soft-tissue augmentation by applying the early implant placement protocol. The distal roots of the maxillary second and third premolars were extracted in 10 mongrel dogs. After 1 month, early implant placement was performed in the distal roots, resulting in buccal dehiscence defects. Four treatments were then randomly applied: (1) guided bone regeneration (GBR), (2) connective tissue grafting (CTG), (3) simultaneous GBR and CTG (GBR + CTG) and (4) no further treatment (control). Healing abutments were connected to all implants to allow non-submerged healing. At 4 and 16 weeks, tissue sections were harvested and histomorphometric analyses were performed. Group GBR presented the largest total tissue thickness at 4 weeks, but underwent a greater remodelling compared with the other groups between 4 and 16 weeks. At 16 weeks, the overall tissue thickness was largest in group GBR + CTG. This group was also the most favourable in terms of the level of the margo mucosae and the presence of mineralized tissue at the coronal level. Group CTG demonstrated a stable tissue thickness over time, with a larger thickness at 16 weeks compared with group GBR. Simultaneous CTG and GBR resulted in the most-favourable tissue thickness when applying the early implant placement protocol.

Double layer graft technique for horizontal alveolar ridge augmentation with staged implant placement: radiographic histological and implant stability analysis–a case report

IntroductionHorizontal ridge augmentation of a deficient alveolar bone site is performed either simultaneously with implant placement or in a staged approach prior to implant insertion. There are several available strategies for the augmentation of alveolar ridge deficiencies, including guided bone regeneration (GBR) through the use of barrier membranes. The success of the GBR approach mainly depends on the exclusion of soft tissue cells during bone remodeling.Case presentationA healthy 25-year-old male patient presented with a missing upper left central incisor after clinical and radiographic examination, the site showed a class III defect horizontal atrophy. The procedure performed was the horizontal alveolar ridge augmentation using resorbable pericardium membrane with double layer graft technique (DLT) where autogenous bone placed as a first layer of the graft followed by xenograft as a second layer, the membrane was fixed with titanium pins. A cone beam computed tomography (CBCT) was performed before, immediately and 6 month following the surgery. After 6 months during implant placement, a core biopsy specimen was retrieved, stored and prepared for histological evaluation, with assessment of primary implant stability. The radiographic analysis showed a horizontal width gain of about 4 mm, at 6 month following implant placement, the implant was successfully osteointegrated with stability assessment also done after 6 months from placement.ConclusionDLT was successfully used for horizontal alveolar ridge augmentation, thus allowing a prosthetically driven implant placement. More cases assessing implant survival and success are needed to confirm the results of this case report.

Microsurgery in periodontics and oral implantology: a systematic review of current clinical applications and outcomes.

The aim of this systematic review was to comprehensively explore the current trends and therapeutic approaches in which an operating microscope (OM) is used in periodontics and dental implant surgeries. A systematic search strategy was built to detect studies including various surgical techniques performed under an OM. PubMed, EMBASE, and SCOPUS databases were searched. No limitations in terms of time and language were applied. The data regarding the study design, type of procedure, treatment groups, and surgical outcomes were collected and analyzed descriptively. In addition, a bibliometric analysis was performed concerning the co-authorship and keyword co-occurrence network. Out of 1985 articles, finally, 55 met the inclusion criteria. Current periodontal and implant microsurgery trends consist of: periodontal therapy, dental implant microsurgery, soft tissue grafting and periodontal plastic surgery, bone augmentation, ridge preservation, and ortho-perio microsurgery. The bibliometric analysis revealed "guided tissue regeneration", "periodontal regeneration" and "root coverage" being the most repeated keywords (landmark nodes). 132 authors within 29 clusters were identified, publishing within the frameworks of "periodontal and implant microsurgery". Within its limitations, this systematic review provides an overview of the latest trends in periodontal and implant microsurgery when considering the use of an OM as the magnification tool. Also, it discusses the reported success and outcomes of the mentioned procedures.

Efficacy of the Sausage Technique in Rebuilding the Crestal Buccal Bone Thickness: A Retrospective Analysis.

The goal was to evaluate the efficacy of the sausage technique in reconstructing the crestal buccal bone thickness, focusing on the distribution shape of the regenerated volume. Ten implants were placed in five patients with Cawood-Howell class IV defects. A cone beam computed tomography (CBCT) was executed at T0 (before surgery). Guided bone regeneration (GBR) with the sausage technique utilized a resorbable collagen membrane, made of a 50% autologous bone and a 50% anorganic bovine bone matrix (ABBM) mixture. After 6 months, a CBCT (T1) was performed before implant placement. Using CBCT software, a plane parallel to the implant axis intersected perpendicular planes every 1.5 mm from the crest level. T0 and T1 CBCT sections were analyzed, yielding 140 measurements. Statistical analysis via SPSS revealed a significant increase in thickness (average 2.82 ± 1.79 mm). Maximum gains occurred at 4.5 mm from the coronal crest line (3.8 ± 1.51 mm). The GBR sausage technique was effective with minimal post-operative complications, yielding the biggest gain at the mid-ridge sagittal area. Within the analysis limitations, it can be assumed that the sausage technique is effective for horizontal GBR in the maxilla, but a lesser volume might be achieved at the crestal level because it seems to follow a bowed regeneration shape.

Characterization of Blow-Spun Polyurethane Scaffolds-Influence of Fiber Alignment and Fiber Diameter on Pericyte Growth.

In this study, fibrous polyurethane (PU) materials with average fiber diameter of 200, 500, and 1000 nm were produced using a solution blow spinning (SBS) process. The effects of the rotation speed of the collector (in the range of 200-25 000 rpm) on the fiber alignment and diameter were investigated. The results showed that fiber alignment was influenced by the rotation speed of the collector, and such alignment was possible when the fiber diameter was within a specific range. Homogeneously oriented fibers were obtained only for a fiber diameter ≥500 nm. Moreover, the changes in fiber orientation and fiber diameter (resulting from changes in the rotation speed of the collector) were more noticeable for materials with an average fiber diameter of 1000 nm in comparison to 500 nm, which suggests that the larger the fiber diameter, the better the controlled architectures that can be obtained. The porosity of the produced scaffolds was about 65-70%, except for materials with a fiber diameter of 1000 nm and aligned fibers, which had a higher porosity (76%). Thus, the scaffold pore size increased with increasing fiber diameter but decreased with increasing fiber alignment. The mechanical properties of fibrous materials strongly depend on the direction of stretching, whereby the fiber orientation influences the mechanical strength only for materials with a fiber diameter of 1000 nm. Furthermore, the fiber diameter and alignment affected the pericyte growth. Significant differences in cell growth were observed after 7 days of cell culture between materials with a fiber diameter of 1000 nm (cell coverage 96-99%) and those with a fiber diameter of 500 nm (cell coverage 70-90%). By appropriately setting the SBS process parameters, scaffolds can be easily adapted to the cell requirements, which is of great importance in producing complex 3D structures for guided tissue regeneration.

Multifunctional bilayer nanofibrous membrane enhances periodontal regeneration via mesenchymal stem cell recruitment and macrophage polarization

The continuous stimulation of periodontitis leads to a decrease in the number of stem cells within the lesion area and significantly impairing their regenerative capacity. Therefore, it is crucial to promote stem cell homing and regulate the local immune microenvironment to suppress inflammation for the regeneration of periodontitis-related tissue defects. Here, we fabricated a novel multifunctional bilayer nanofibrous membrane using electrospinning technology. The dense poly(caprolactone) (PCL) nanofibers served as the barrier layer to resist epithelial invasion, while the polyvinyl alcohol/chitooligosaccharides (PVA/COS) composite nanofiber membrane loaded with calcium beta-hydroxy-beta-methylbutyrate (HMB-Ca) acted as the functional layer. Material characterization tests revealed that the bilayer nanofibrous membrane presented desirable mechanical strength, stability, and excellent cytocompatibility. In vitro, PCL@PVA/COS/HMB-Ca (P@PCH) can not only directly promote rBMSCs migration and differentiation, but also induce macrophage toward pro-healing (M2) phenotype-polarization with increasing the secretion of anti-inflammatory and pro-healing cytokines, thus providing a favorable osteoimmune environment for stem cells recruitment and osteogenic differentiation. In vivo, the P@PCH membrane effectively recruited host MSCs to the defect area, alleviated inflammatory infiltration, and accelerated bone defects repair. Collectively, our data indicated that the P@PCH nanocomposite membrane might be a promising biomaterial candidate for guided tissue regeneration in periodontal applications.

Biodegradable quaternized silk fibroin sponge with highly uniform pore structure for traumatic hemostasis and anti-infection

Developing a biodegradable sponge with rapid shape recovery and potent antibacterial and coagulation properties for traumatic hemostasis and anti-infection remains challenging. Herein, we fabricated quaternized silk fibroin (SF) sponges by freeze-drying under a constant cooling rate and modification with quaternary ammonium groups. We found the constant cooling rate enabled the sponges with a highly uniform pore structure, which provided excellent self-elasticity and shape recovery. Decoration with quaternary ammonium groups enhanced blood cells adhesion, aggregation, and activation, as well as resistance to infections from Staphylococcus aureus and Escherichia coli. The SF sponge had superior hemostatic capacity to gauze and commercial gelatin sponge in different hemorrhage models. The SF sponge exhibited favorable biodegradability and biocompatibility. Moreover, The SF sponge also promoted host cell infiltration, capillary formation, and tissue ingrowth, suggesting its potential for guiding tissue regeneration. The developed SF sponge holds great application prospects for traumatic hemostasis, anti-infection, and guiding tissue regeneration.

Enhancing guided bone regeneration with cross-linked collagen-conjugated xenogeneic bone blocks and membrane fixation: A preclinical invivo study.

To determine whether combining cross-linked (CL) collagen-integrated xenogeneic bone blocks stabilized with the fixation of resorbable collagen membranes (CM) can enhance guided bone regeneration (GBR) in the overaugmented calvarial defect model. Four circular defects with a diameter of 8 mm were prepared in the calvarium of 13 rabbits. Defects were randomly assigned to receive one of the following treatments: (i) non-cross-linked (NCL) porcine-derived collagen-embedded bone block covered by a CM without fixation (NCL + unfix group); (ii) NCL bone block covered by CM with fixation using bone-tack (NCL + fix group); (iii) cross-linked (CL) porcine-derived collagen-embedded bone block covered by CM without fixation (CL + unfix group); and (iv) CL bone block covered by CM with fixation using bone-tack fixation (CL + fix group). The efficacy of GBR was assessed through histological and molecular analyses after 2 and 8 weeks. At 2 weeks, there were no significant differences in histologically measured areas of newly formed bone among the groups. At 8 weeks, however, the CL + fix group exhibited a larger area of new bone (5.08 ± 1.09 mm2, mean ± standard deviation) compared to the NCL + unfix (1.62 ± 0.42 mm2; p < .0083), NCL + fix (3.97 ± 1.39 mm2) and CL + unfix (2.55 ± 1.04 mm2) groups. Additionally, the expression levels of tumour necrosis factor-alpha, fibroblast growth factor-2, vascular endothelial growth factor, osteocalcin and calcitonin receptor were significantly higher in the CL + fix group compared to the other three groups (p < .0083). Cross-linked bone blocks stabilized with collagen membrane fixation can significantly enhance GBR.

Dynamic Transcriptome Analysis of SFRP Family in Guided Bone Regeneration With Occlusive Periosteum in Swine Model.

A variety of congenital or acquired conditions can cause craniomaxillofacial bone defects, resulting in a heavy financial burden and psychological stress. Guided bone self-generation with periosteum-preserved has great potential for reconstructing large bone defects. A swine model of guided bone regeneration with occlusive periosteum was established, the rib segment was removed, and the periosteum was sutured to form a closed regeneration chamber. Hematoxylin and eosin staining, Masson's staining, and Safranine O-Fast Green staining were done. Nine-time points were chosen for collecting the periosteum and regenerated bone tissue for gene sequencing. The expression level of each secreted frizzled-related protein (SFRP) member and the correlations among them were analyzed. The process of bone regeneration is almost complete 1 month after surgery, and up to 1 week after surgery is an important interval for initiating the process. The expression of each SFRP family member fluctuated greatly. The highest expression level of all members ranged from 3 days to 3 months after surgery. The expression level of SFRP2 was the highest, and the difference between 2 groups was the largest. Secreted frizzled-related protein 2 and SFRP4 showed a notable positive correlation between the control and model groups. Secreted frizzled-related protein 1, SFRP2, and SFRP4 had a significant spike in fold change at 1 month postoperatively. Secreted frizzled-related protein 1 and SFRP2 had the strongest correlation. This study revealed the dynamic expression of the SFRP family in guided bone regeneration with occlusive periosteum in a swine model, providing a possibility to advance the clinical application of bone defect repair.