Tissue Sealants Research Articles

Sticky Science: Using Complex Coacervate Adhesives for Biomedical Applications.

Tissue adhesives are used for various medical applications, including wound closure, bleeding control, and bone healing. Currently available options often show weak adhesion or cause adverse effects. Recently, there has been an increasing interest in complex coacervates as medical adhesives. Complex coacervates are formed by mixing oppositely charged macromolecules that associate and undergo liquid-liquid phase separation, in which the dense bottom phase is the complex coacervate. Complex coacervates are strong and often biocompatible, and show strong underwater adhesion. The properties of the resulting materials are tunable by intrinsic factors such as polymer chemistry, molecular weight, charge density, and topology of the macromolecules, as well as extrinsic factors such as temperature, pH, and salt concentration. Therefore, complex coacervates are interesting new candidates for medical adhesives. In this review, it is described how complex coacervates form and how different factors influence their behavior. Next, an overview of recent studies on complex coacervates in the context of medical adhesives is presented. The application of complex coacervates as hemostatic or embolic agents, skin or bone repair adhesives, and soft tissue sealants is discussed. Lastly, additional possibilities for utilizing these materials in the future are discussed.

Endoscopic management of Boerhaave syndrome: a comprehensive review of techniques, outcomes and future directions

Boerhaave syndrome, characterized by spontaneous esophageal rupture, presents a critical condition requiring prompt diagnosis and intervention to reduce morbidity and mortality. Traditionally managed with surgical intervention, advancements in endoscopic techniques have emerged as viable alternatives, offering less invasive options with promising outcomes. This article provides a thorough review of the endoscopic management of Boerhaave syndrome, detailing the indications, techniques, and outcomes associated with various endoscopic approaches. We examine the role of esophageal stenting, clipping, and tissue sealants, alongside adjunctive therapies. Furthermore, we discuss patient selection criteria, procedural considerations, and potential complications. Our review highlights the evolving landscape of Boerhaave syndrome management, underscoring the importance of multidisciplinary collaboration and the need for further research to optimize patient outcomes.

Preparation of accelerated-wound-healing lignin/dopamine-based nano-Fe3O4 hydrogels in sensing

Flexible conductive hydrogels hold great promise for applications in motion and medical detection. It is difficult to produce conductive hydrogel epidermal sensors in wearable hydrogels with dependable adhesion, sensing, and wound-healing properties. Nano-Fe3O4 was used as physical cross-linking points in the polyacrylamide/polyvinyl alcohol double network (PP) to increase the strain capacity of the hydrogel. The conductive lignin-dopamine (LD) was immobilized on the surface of Fe3O4 particles, and the LD-coated Fe3O4 was then incorporated into the double network hydrogel to create the PP/LD/Fe3O4 hydrogel. This work was done to look into the possibility of using Fe3O4 hydrogels as flexible strain sensors. The addition of LD/Fe3O4 caused the composite hydrogel to strain up to 124 %, with a modulus of elasticity of 21,308 Pa and electrical conductivity as high as 2.3 S•m−1 following the introduction of LD/Fe3O4. Moreover, the PP/LD/Fe3O4 hydrogel's adhesive qualities offered adequate antimicrobial properties and promoted wound healing. These results indicate that the developed electricity-responsive and tissue-adhesive hydrogel dressing offers a candidate to serve as a tissue sealant for wound healing.

Nonoperative Management Strategies for Anastomotic Leaks After One Anastomosis Gastric Bypass (OAGB): A Literature Review.

One Anastomosis Gastric Bypass (OAGB) has gained widespread acceptance as an effective bariatric surgery due to its relative simplicity and favorable outcomes in weight loss and metabolic improvement. However, anastomotic leaks, though uncommon, present a significant complication with the potential for severe morbidity and mortality if not managed appropriately. This review examines the range of nonoperative strategies currently employed to manage anastomotic leaks and fistulae following OAGB. The focus is on endoscopic techniques, including the use of clips, stents, suturing systems, internal drainage, vacuum therapy, and tissue sealants, which have been successfully used in various gastrointestinal surgeries. Although a proportion of patients will require surgical treatments, these strategies offer less invasive alternatives to surgical intervention and can be tailored to the specific characteristics of the leak and patient condition. However, the application of these techniques specifically for OAGB-related leaks is not as well-documented. This review lists the available evidence on these nonoperative approaches, highlighting some of their potential benefits and limitations. While these methods show promise, there is a clear need for further research to establish standardized protocols and optimize their use in the context of OAGB-related leaks and fistulae.

Biocompatibility of mussel-inspired water-soluble tissue adhesives.

Wound closure in surgeries is traditionally achieved using invasive methods such as sutures and staples. Adhesion-based wound closure methods such as tissue adhesives, sealants, and hemostats are slowly replacing these methods due to their ease of application. Although several chemistries have been developed and used commercially for wound closure, there is still a need for better tissue adhesives from the point of view of toxicity, wet-adhesion strength, and long-term bonding. Catechol chemistry has shown great promise in developing wet-set adhesives that meet these criteria. Herein, we have studied the biocompatibility of a catechol-based copolymer adhesive, poly([dopamine methacrylamide]-co-[methyl methacrylate]-co-[poly(ethylene glycol) methyl ether methacrylate]) or poly(catechol-MMA-OEG), which is soluble in water. The adhesive was injected subcutaneously in a mouse model on its own and in combination with a sodium periodate crosslinker. After 72 h, 4 weeks, and 12 weeks, the mice were euthanized and subjected to histopathological analysis. Both adhesives were present and still palpable at the end of 12 weeks. The moderate inflammation observed for the poly(catechol-MMA-OEG) cohort at 72 h had reduced to mild inflammation at the end of 12 weeks. However, the moderate inflammatory response observed for the poly(catechol-MMA-OEG) + crosslinker cohort at 72 h had not subsided at 12 weeks.

Haemostatic biomaterial based on expired platelets for medical applications

Blood loss has been a concern especially in surgery and bleeding control and a number of haemostatic agents and tissue sealants have been developed and applied in various surgical disciplines. The first steps to stop bleeding due to a vascular lesion, limit blood loss and allow healing are ensured by platelets that play an essential role in forming the primary haemostatic plug. After this, the clot is consolidated by the formation of a fibrin network organized around platelet aggregates. In this study we tested for the treatment of external haemorrhagic lesions a new biomaterial based on expired platelets from blood banks immobilized on a collagen support. These platelets are no longer used for transfusions, are safe (tested for viral and bacterial contamination) and still have local haemostatic activity. Collagen is non-toxic, non-antigenic and promotes cell adhesion. Platelets bind to the collagen support and subsequently form clots through the intrinsic coagulation pathway.

Cellulose fibres enhance the function of hemostatic composite medical sealants.

Tissue adhesives and sealants offer promising alternatives to traditional wound closure methods, but the existing trade-off between biocompatibility and strength is still a challenge. The current study explores the potential of a gelatin-alginate-based hydrogel, cross-linked with a carbodiimide, and loaded with two functional fillers, the hemostatic agent kaolin and cellulose fibres, to improve the hydrogel's mechanical strength and hemostatic properties for use as a sealant. The effect of the formulation parameters on the mechanical and physical properties was studied, as well as the biocompatibility and microstructure. The incorporation of the two functional fillers resulted in a dual micro-composite structure, with uniform dispersion of both fillers within the hydrogel, and excellent adhesion between the fillers and the hydrogel matrix. This enabled to strongly increase the sealing ability and the tensile strength and modulus of the hydrogel. The fibres' contribution to the enhanced mechanical properties is more dominant than that of kaolin. A combined synergistic effect of both fillers resulted in enhanced sealing ability (247%), tensile strength (400%), and Young's modulus (437%), compared to the unloaded hydrogel formulation. While the incorporation of kaolin almost did not affect the physical properties of the hydrogel, the incorporation of the fibres strongly increased the viscosity and decreased the gelation time and swelling degree. The cytotoxicity tests indicated that all studied formulations exhibited high cell viability. Hence, the studied new dual micro-composite hydrogels may be suitable for medical sealing applications, especially when it is needed to get a high sealing effect within a short time. The desired hemostatic effect is obtained due to kaolin incorporation without affecting the physical properties of the sealant. Understanding the effects of the formulation parameters on the hydrogel's properties enables the fitting of optimal formulations for various medical sealing applications.

Moldable Tissue-Sealant Hydrogels Composed of In Situ Cross-Linkable Polyethylene Glycol via Thiol-Michael Addition and Carbomers.

Moldable tissue-sealant hydrogels were developed herein by combining the yield stress fluidity of a Carbomer and in situ cross-linking of 3-arm PEG-thiol (PEG-SH) and 4-arm PEG-acrylate (PEG-AC). The Carbomer was mixed with each PEG oligomer to form two aqueous precursors: Carbomer/PEG-SH and Carbomer/PEG-AC. The two hydrogel precursors exhibited sufficient yield stress (>100 Pa) to prevent dripping from their placement on the tissue surface. Moreover, these hydrogel precursors exhibited rapid restructuring when the shear strain was repeatedly changed. These rheological properties contribute to the moldability of these hydrogel precursors. After mixing these two precursors, they were converted from yield-stress fluids to chemically cross-linked hydrogels, Carbomer/PEG hydrogel, via thiol-Michael addition. The gelation time was 5.0 and 11.2 min at 37 and 25 °C, respectively. In addition, the Carbomer/PEG hydrogels exhibited higher cellular viability than the pure Carbomer. They also showed stable adhesiveness and burst pressure resistance to various tissues, such as the skin, stomach, colon, and cecum of pigs. The hydrogels showed excellent tissue sealing in a cecum ligation and puncture model in mice and improved the survival rate due to their tissue adhesiveness and biocompatibility. The Carbomer/PEG hydrogel is a potential biocompatible tissue sealant that surgeons can mold. It was revealed that the combination of in situ cross-linkable PEG oligomers and yield stress fluid such as Carbomer is effective for developing the moldable tissue sealant without dripping of its hydrogel precursors.

415 Cryopreserved Human Umbilical Cord in the Treatment of Pediatric Tethered Cord Syndrome

INTRODUCTION: Tethered cord syndrome (TCS) is characterized by neurological, gastrointestinal/genitourinary, and musculoskeletal dysfunction attributable to spinal cord traction. It is estimated that 20-50% of children with open and closed neural tube defects repaired after birth will require surgery to detether the spinal cord. The cryopreserved human umbilical cord (HUC) patch has regenerative, anti-inflammatory, and anti-scarring properties. In animal models, when HUC is used as a meningeal patch it allows regeneration of the arachnoid layer, prevents spinal cord tethering, and improves spinal cord function after in utero spina bifida repair. We hypothesized that this would benefit pediatric patients requiring detethering. METHODS: Serial patients with clinical and radiographic evidence of a tethered cord were enrolled following informed consent. At the time of surgery they underwent spinal cord detethering with neuromonitoring. At the time of closure a HUC graft (Clarix 1k) was placed as a dural underlay, the dura was closed primarily, and a second graft was placed as a dural overlay and sealed with tissue sealant. Serial neurologic assessments and urologic assessments were obtained. MRIs are performed annually or as indicated clinically. RESULTS: Four patients have been detethered with use of HUC as a dural underlay and overlay (2 lipomyelomeningocele, 1 lipoma/diastematomyelia, 1 tethered cord). One patient remains neurointact, with resolution of mild neurogenic bladder. Another patient has gained sensation of lower extremities, sensation to catheterization, with resolution of neurogenic bowel and bladder. One has gained sensation to catheterization, with resolution of neurogenic bowel and bladder. The fourth patient is stable. CONCLUSIONS: Early use of HUC as a dural underlay and overlay during closure for tethered cord surgery shows promise in improving spinal cord function in pediatric patients.

All-in-one tissue adhesive hydrogels for topical wound care

An adhesive tissue sealant that enables rapid formation of new granulation tissue while leading to additional synthesis of extracellular matrix (ECM) to promote tissue regeneration is strongly required in the clinical field. This study presents an all-in-one wound care hydrogel sealant that generates cohesion in response to pH change while adhering stably to tissue. To fulfill this, we employ an injectable boronic acid-conjugated alginate (Al-BA) aqueous sol phase that turns into a soft viscoelastic hydrogel gel phase at physiological pH conditions, thus filling in wounds of any size or depth. Positively charged bacterial cellulose nanofibers ((+)BCNF) are incorporated to reinforce this gel. Compared to the only Al-BA adhesive, the resulting Al-BA/(+)BCNF adhesive hydrogel exhibits substantial adhesion strength while retaining the wound closure even with external mechanical perturbation such as stretching, bending and twisting. Furthermore, in vitro and in vivo wound healing evaluations revealed that fibrous (+)BCNF provides favorable microenvironment for cell migration and proliferation similar to collagen fibers, promoting wound healing and skin regeneration.

Tissue Sealant Impact on Skull Base Reconstruction Outcomes: A Systematic Review and Meta-Analysis.

Despite significant advances in understanding of skull base reconstruction principles, the role of tissue sealants in modifying postoperative cerebrospinal fluid (CSF) leak outcomes remains controversial. We evaluate postoperative CSF leak incidence associated with tissue sealant use in skull base defect repair during endoscopic skull base surgery (ESBS). Web of Science, PubMed/MEDLINE, Scopus, and Cochrane Library. Systematic review and meta-analysis of risk differences (RD). A search strategy identified original studies reporting CSF leakage following ESBS with disaggregation by tissue sealant use and/or type. 27 non-randomized studies (n = 2,403) were included for qualitative and meta-analysis. Reconstruction with a tissue sealant did not significantly reduce postoperative CSF leak risk compared with reconstruction without sealant (RD[95% CI] = 0.02[-0.01, 0.05]). Sub-analyses of dural sealant (-0.02[-0.11, 0.07]) and fibrin glue (0.00[-0.07, 0.07]) compared with no sealant were similarly unremarkable. Postoperative CSF leakage was not significantly modulated in further sub-analyses of DuraSeal (0.02[-0.02, 0.05]), Adherus (-0.03[-0.08, 0.03]), or Bioglue (-0.06[-0.23, 0.12]) versus no dural sealant use, or Tisseel/Tissucol versus fibrin glue nonuse (0.00[-0.05, 0.05]). No significant association was seen comparing dural sealant use versus fibrin glue use on pairwise (0.01[-0.03, 0.05]) or network meta-analysis (-0.01[-0.05, 0.04]). Limitations in source literature prevented sub-analyses stratified by leak characteristics, defect size and location, and accompanying reconstruction materials. Tissue sealant use did not appear to impact postoperative CSF leak incidence when compared with nonuse. Higher quality studies are warranted to thoroughly elucidate the clinical value of adjunct sealant use in endoscopic skull base reconstruction. N/A Laryngoscope, 134:3425-3436, 2024.

Injectable-Hydrogel-Based Tissue Sealant for Hemostasis, Bacteria Inhibition, and Pro-Angiogenesis in Organ Bleeding Wounds and Therapeutic Outcome Monitoring Via NIR-II Optical Imaging.

Sudden hemorrhage stemming from internal organ wounds poses a grave and potentially fatal risk if left untreated. Injectable-hydrogel-based tissue sealants featuring multiple actions, including fit-to-shape in situ gelation, rapid hemostasis, pro-angiogenic, anti-bacterial and outcome tracking, are ideal for the management of organ trauma wounds. Herein, an injectable-hydrogel tissue sealant AN@CD-PEG&TQ which consists of four-arm 4-arm poly(ethylene glycol) (PEG-SC) succinimidyl carbonate), AN@CD nanoprobe, and two bioactive peptides (anti-microbial peptide Tet213 and pro-angiogenic peptide QK) is developed. Among them, AN@CD nanoparticles form through host/guest complexation of amino-group-containing β-cyclodextrin and adamantyl group, enabling in situ biomarker (NO)-activatable optoacoustic/NIR-II: Near-infrared second biological window fluorescent imaging. The ample ─NH2 groups on the surface of AN@CD readily engage in rapid cross-linking with succinimidyl ester groups located at the ends of four-arm PEG-SC. This cross-linking expedites the gelation process without necessitating additional initiators or cross-linking agents; thus, significantly enhancing both hydrogel's application convenience and biocompatibility. Bioactive peptides (Tet213 and QK) safeguard against possible bacterial infections, facilitate angiogenesis, and eventually, improve organ wounds healing. This hydrogel-based tissue sealant demonstrates superior therapeutic and bioimaging performance in various mouse models including liver hemorrhage, gastric perforation, and bacterial-infected skin wound mouse models, highlighting its potential as a high-performance wound sealant for organ bleeding wound management.

The benefit of tissue sealant on urethroplasty in hypospadias patients - A systematic review and meta-analysis.

Hypospadias was ranked second after undescended testis as the most prevalent congenital abnormality in newborn males. Hypospadias can be successfully repaired through multiple surgeries in the majority of children. Postoperative complications were not rarely seen after surgeries, such as urethrocutaneous fistula (UCF), meatal stenosis, and glans breakdown. Tissue sealant application in hypospadias repair serves as additional suture line coverage and reduces the post surgery complications. However, the effects of sealants usage during urethroplasty are still uncertain. This review aimed to know the effects of tissue sealant usage on patients with hypospadias who undergo urethroplasty. The study was reported based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Literature was searched on PubMed, Embase, and Scopus following PRISMA guidelines. The search was conducted on October 12th, 2021, using the search term ("glue" OR "sealants" OR "tissue glue" OR "tissue sealant" OR "tissue adhesive") AND ("hypospadias" OR "urethrocutaneous fistula" OR "urethral repair" OR "urethroplasty" OR "hypospadiology"). Systematic searching from all databases resulted in 160 potential articles. After a full-text review, eight articles were included in this study. Urethrocytaneous fistula complication was reported in all studies. The occurrence of complication reported by all studies was urethrocutaneous fistula. Several studies also reported tissue edema and flap-related complications. Tissue sealant had no significant effect in reducing meatal stenosis. This systematic review revealed additional benefits from several types of tissue sealant in hypospadias repair surgery. Fibrin sealant application over the urethroplasty suture line in hypospadias repair offers a water-proof coverage and may enhance the outcome from the surgery.

Clinical and technical factors in endoscopic skull base surgery associated with reconstructive success.

In this study, we identified key discrete clinical and technical factors that may correlate with primary reconstructive success in endoscopic skull base surgery (ESBS). ESBS cases with intraoperative cerebrospinal fluid (CSF) leaks at four tertiary academic rhinology programs were retrospectively reviewed. Logistic regression identified factors associated with surgical outcomes by defect subsite (anterior cranial fossa [ACF], suprasellar [SS], purely sellar, posterior cranial fossa [PCF]). Of 706 patients (50.4% female), 61.9% had pituitary adenomas, 73.4% had sellar or SS defects, and 20.5% had high-flow intraoperative CSF leaks. The postoperative CSF leak rate was 7.8%. Larger defect size predicted ACF postoperative leaks; use of rigid reconstruction and older age protected against sellar postoperative leaks; and use of dural sealants compared to fibrin glue protected against PCF postoperative leaks. SS postoperative leaks occurred less frequently with the use of dural onlay. Body-mass index, intraoperative CSF leak flow rate, and the use of lumbar drain were not significantly associated with postoperative CSF leak. Meningitis was associated with larger tumors in ACF defects, nondissolvable nasal packing in SS defects, and high-flow intraoperative leaks in PCF defects. Sinus infections were more common in sellar defects with synthetic grafts and nondissolvable nasal packing. Depending on defect subsite, reconstructive success following ESBS may be influenced by factors, such as age, defect size, and the use of rigid reconstruction, dural onlay, and tissue sealants.

ECM-based bioadhesive hydrogel for sutureless repair of deep anterior corneal defects.

Corneal transplantation is the gold standard treatment for corneal-related blindness; however, this strategy faces challenges such as limited donor cornea, graft rejection, suture-related complications, and the need for specialized equipment and advanced surgical skills. Development of tissue adhesives for corneal regeneration is of great clinical value. However, currently available corneal tissue sealants pose challenges, such as lack of safety, biocompatibility, and desired mechanical properties. To meet these requirements simultaneously, a bovine stromal corneal extracellular matrix (dCor) was used to design a bioadhesive photocurable hydrogel based on gelatin methacrylate (GelMA) and polyethylene glycol diacrylate (PEGDA) hydrogels (dCor/Gel-PEG). Integration of dCor into the dual networks of GelMA and PEGDA (Gel-PEG) led to a bioadhesive hydrogel for curing corneal defects, which could be crosslinked by Irgacure 2959 within 5 min ultraviolet irradiation. The viability of corneal stromal stem cells (CSSCs) was improved on the dCor/Gel-PEG hydrogel in comparison to the Gel-PEG hydrogel. The gene expression profile supported the keratocyte differentiation of CSSCs seeded on dCor/Gel-PEG via increased KERA and ALDH, with inhibited myofibroblast transdifferentiation via decreased α-SMA due to the presence of dCor. Interestingly, the dCor/Gel-PEG hydrogel exhibited favorable mechanical performance in terms of elasticity and bioadherence to the host corneal stroma. Ex vivo and in vivo examinations proved the feasibility of this hydrogel for the sutureless reconstruction of deep anterior corneal defects with promising histopathological results.

Endoscopic Intervention for Anastomotic Leakage After Gastrectomy.

Anastomotic leaks and fistulas are significant complications of gastric surgery that potentially lead to increased postoperative morbidity and mortality. Surgical intervention is reserved for cases with severe symptoms or hemodynamic instability; however, surgery carries a higher risk of complications. With advancements in endoscopic treatment options, endoscopic approaches have emerged as the primary choice for managing these complications. Endoscopic clipping is a traditional method comprising 2 main categories: through-the-scope clips and over-the-scope clips. Through-the-scope clips are user friendly and adaptable to various clinical scenarios, whereas over-the-scope clips can close larger defects. Another promising approach is endoscopic stent insertion, which has shown a high success rate for leak closure, although vigilant monitoring is required to monitor stent migration. Infection control is essential in post-surgical leakage cases, and endoscopic internal drainage provides a relatively safe and noninvasive means to manage fluids, contributing to infection control and wound healing promotion. Endoscopic suturing offers full-thickness wound closure, but requires additional training and endoscopic versatility. As a promising tool, endoscopic vacuum therapy potentially surpasses stent therapy by draining inflammatory materials and closing defects. Furthermore, the use of tissue sealants, such as fibrin glue and cyanoacrylate, has been reported to be effective in selected situations. The choice of endoscopic device should be tailored to individual cases and specific patient conditions, with careful consideration of the nature of the defect. Further extensive studies involving larger patient populations are required to provide more robust evidence on the efficacy of endoscopic approach in managing post-gastric anastomotic leaks.

Limited Incision Facelifts: A Contemporary Review of Approaches and Complications.

Limited incision facelifts (LIFs) have gained popularity as an alternative to traditional facelift procedures. While surgical techniques vary, these approaches share a common goal: to rejuvenate the face while minimizing scar visibility. Previous studies also suggest that the reduced tissue dissection in LIFs can lead to decreased postoperative swelling, shorter recovery periods, and fewer complications. In this systematic review we delved into the literature on LIFs, shedding light on the various surgical approaches and their respective safety profiles. A systematic review was conducted by independent evaluators who followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A random-effects model was utilized to summarize complications data, and meta-regressions were conducted to analyze associations with operative variables. The analysis encompassed a total of 20 articles, comprising data from 4451 patients. The vast majority (84%) of these patients underwent either local wide-awake surgery or conscious sedation, while the remaining 16% underwent general anesthesia. Our analysis revealed an overall complication frequency of 3.2%, with hematoma being the most common complication (2%), followed by temporary nerve injury (0.2%), and skin necrosis or wounds (0.06%). Notably, hematomas rarely required operating room interventions. Use of drains or tissue sealants was associated with an 86% decrease in complications. Limited incision facelifts can be performed with a low complication rate, utilizing a variety of techniques. Utilization of tissue sealants and drains may limit hematoma formation, which is the most common complication.

Validation of Efficacy and Safety of TachoSil ® Tissue Sealant for Vessel Transposition in Microvascular Decompression.

Use of TachoSil ® as the transposition material of microvascular decompression (MVD) for hemifacial spasm (HFS) and trigeminal neuralgia (TN) is easy and safe to perform, but the efficacy and safety of this technique are unknown. This study attempted to validate the efficacy and safety of TachoSil ® as a transposition material of MVD. A retrospective study of the surgical results and complications of 63 patients (35 HFS and 28 TN) treated by the TachoSil ® technique between January 2011 and December 2021 was conducted. The efficacy of the treatment was evaluated by Kaplan-Meier survival analysis. Magnetic resonance imaging follow-up study was performed to detect any adverse events including a mass formation. The rate of complete disappearance of HFS was 91.4% at 1 year and estimated to be 85.7% after a 10-year follow-up. The rate of no pain without medication for TN was 85.4% at 1 year and estimated to be 69.0% after a 9-year follow-up. These surgical results are comparable with those previously reported. Flaking of TachoSil ® releasing the offending artery was only recognized in one case (1.6%). Therefore, TachoSil ® can be considered as an effective transposition material for MVD. TachoSil ® did not increase the rate of acute and subacute adverse events such as inflammation and delayed facial palsy. Magnetic resonance imaging follow-up identified no abnormalities including mass that suggested granuloma formation. The efficacy of the TachoSil ® technique for HFS and TN and the reliability of TachoSil ® as an adhesive material in MVD were verified. No adverse events associated with TachoSil ® use in MVD were found. We conclude that the TachoSil ® technique has relatively long efficacy and safety for MVD.

Wet adhesion enhancement through citric-acid-regulated supramolecular network

Adhesion on wet surface is of significance but remains challenging. Despite large steps forward in wet adhesives, they suffer from complicated preparation procedures and unbalanced properties. Herein, we develop a simple one-pot approach to fabricate a supramolecular adhesive with simultaneous enhancement in wet adhesion and mechanical toughness, which is achieved via citric acid (CA)-regulated supramolecular network of N-hydroxy succinimide (NHS) grafted polyacrylic acid chain and gelatin. CA not only reinforces supramolecular network by forming abundant hydrogen bonds, but also repels the NHS groups exposed outward to increase the opportunity for bonding with the target surface. The resultant adhesive shows fast and robust wet adhesion, high mechanical strength and elongation, as well as good biocompatibility. Such features enable the resultant adhesive with high potential in a variety of biomedical settings, such as tissue adhesion, sealant, and skin-adhesive strain sensor. This study opens a new avenue for the development of advanced bioadhesives, holding broad clinical application prospects.

Evaluation and comparison of the efficacy of autologous fibrin glue with 4-0 silk sutures in periodontal flap closure and wound healing - A split mouth randomized controlled trial.

Fibrin glue has shown to be a pioneering remedy to overcome the inconvenience of suturing. Autologous products reduce the risk of contamination and immunological responses compared to commercial fibrin glue. Hence using autologous fibrin glue (AFG) as a tissue sealant in periodontal flap closure would be of added value for a predictable outcome. To evaluate and compare the efficacy of AFG with 4-0 silk sutures in periodontal flap closure and healing. Total of 17 patients diagnosed with generalized periodontitis in the age group of 18 to 60years with probing pocket depth of ≥ 6mm and clinical attachment level of ≥5mm in at least two quadrants were categorized into test group (AFG) and control group (4-0 silk sutures). Primary outcome measures [modified gingival index (MGI), early wound index (EHI) and interleukin 1 beta (IL-1ß) and secondary outcome measures (oral hygiene index, plaque index and visual analog scale (VAS) were recorded at baseline, 1, 2, 3 and 4 weeks. A statistically significant reduction of IL-1ß value (p =.005); MGI (p = .02); EHI (p = .004), VAS scores (p < .001) and a positive Spearman's correlation (rho = 0.15) was seen between EHI scores & IL-1ß levels in test group at 1week period in comparison to control group. AFG showed promising results as an alternative to sutures. The use of AFG significantly improved clinical parameters and reduced the levels of pro-inflammatory cytokines making it an effective adhesive with healing properties in the era of suture-less periodontal flap surgery.