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Sample records for fibrin sealant patch

  1. A hospital cost analysis of a fibrin sealant patch in soft tissue and hepatic surgical bleeding

    PubMed Central

    Corral, Mitra; Ferko, Nicole; Hogan, Andrew; Hollmann, Sarah S; Gangoli, Gaurav; Jamous, Nadine; Batiller, Jonathan; Kocharian, Richard

    2016-01-01

    Background Despite hemostat use, uncontrolled surgical bleeding is prevalent. Drawbacks of current hemostats include limitations with efficacy on first attempt and suboptimal ease-of-use. Evarrest® is a novel fibrin sealant patch that has demonstrated high hemostatic efficacy compared with standard of care across bleeding severities. The objective of this study was to conduct a hospital cost analysis of the fibrin sealant patch versus standard of care in soft tissue and hepatic surgical bleeding. Methods The analysis quantified the 30-day costs of each comparator from a hospital perspective. Published US unit costs were applied to resource use (ie, initial treatment, retreatment, operating time, hospitalization, transfusion, and ventilator) reported in four trials. A “surgical” analysis included resources clinically related to the hemostatic benefit of the fibrin sealant patch, whereas a “hospital” analysis included all resources reported in the trials. An exploratory subgroup analysis focused solely on coagulopathic patients defined by abnormal blood test results. Results The surgical analysis predicted cost savings of $54 per patient with the fibrin sealant patch compared with standard of care (net cost impact: −$54 per patient; sensitivity range: −$1,320 to $1,213). The hospital analysis predicted further cost savings with the fibrin sealant patch (net cost impact of −$2,846 per patient; sensitivity range: −$1,483 to −$5,575). Subgroup analyses suggest that the fibrin sealant patch may provide dramatic cost savings in the coagulopathic subgroup of $3,233 (surgical) and $9,287 (hospital) per patient. Results were most sensitive to operating time and product units. Conclusion In soft tissue and hepatic problematic surgical bleeding, the fibrin sealant patch may result in important hospital cost savings. PMID:27703386

  2. Efficacy and safety of fibrin sealant patch in the treatment of air leakage in thoracic surgery.

    PubMed

    Lopez, C; Facciolo, F; Lequaglie, C; Rendina, E A; Saita, S; Dell'Amore, D; Sollitto, F; Urciuoli, G; Loizzi, M; Cisternino, M L; Granone, P; Angelelli, A; Cardillo, G; Mucilli, F; Di Rienzo, G

    2013-12-01

    Air leakage represents a major problem in lung surgery. Absorbable fibrin sealant patch (AFSP), a collagen sponge coated with human fibrinogen and thrombin, can be used as an adjunct to primary stapling or suturing. This study compared the efficacy of AFSP with manual suturing after primary stapling. This was a prospective, multicenter, randomized study. Patients undergoing lobectomy, bilobectomy, anatomical segmentectomy for lung cancer or wedge resection for pulmonary metastasis with air leakage grade 1 or 2 according to Macchiarini scale after stapler suture were randomized to receive AFSP or standard surgical treatment (ST). The primary endpoint was the reduction of intraoperative air leakage intensity. Duration of postoperative air leakage and number of days until removal of last chest drain were secondary endpoints. Safety was recorded for all patients. A total of 346 patients were enrolled in 14 centres, 179 of whom received AFSP and 167 ST. Intraoperative air leak intensity was reduced in 90.5% of AFSP patients and 82% of ST patients (P=0.03). A significant reduction in postoperative air leakage duration was observed in the AFSP group (P=0.0437). The median number of days until removal of last drainage was 6 (3-37) in the AFSP group and 7 (2-27) in the ST (P=0.38). Occurrence of adverse events was comparable in both groups. AFSP was more efficacious than standard ST as an adjunct to primary stapling in reducing intraoperative air leakage intensity and duration of postoperative air leakage in patients undergoing pulmonary surgery. AFSP was well tolerated.

  3. The safety of fibrin sealants.

    PubMed

    Joch, Christine

    2003-08-01

    Fibrin sealants are prepared from fibrinogen, thrombin and sometimes also factor XIII that have been purified from human plasma. Bovine aprotinin is also included in some preparations. Each of these components has the potential to carry blood-borne pathogens, albeit at a very low frequency. In order to minimize the risk of viral transmission from commercial fibrin sealants, plasma donations undergo a series of procedures that contribute to avoiding, inactivating and eliminating potential contaminants. The procedures for selection and screening of plasma donors, and the testing of donated plasma, incorporates highly sensitive molecular techniques (e.g. PCR testing) and contributes significantly to reducing the theoretical possibility of viral transmission. The starting material for bovine aprotinin is also carefully selected, and the manufacturing process rigorously assessed, to minimize the putative risk of transmission of bovine spongiform encephalopathies. The manufacturing process for commercial fibrin sealants comprises a range of procedures, including heat treatment (e.g. pasteurization, dry or vapor heating), filtration, solvent/detergent treatment, precipitation, pH treatment and chromatography. Some steps are an inherent part of the purification process and others (e.g. pasteurization, nanofiltration) are deliberately introduced to inactivate/eliminate potential pathogens. Current manufacturing processes provide a very high degree of safety for fibrin sealants. In 20 years of worldwide use, there have been no known cases of hepatitis or HIV transmission associated with the use of commercial fibrin sealants.

  4. Fibrin Sealant: The Only Approved Hemostat, Sealant, and Adhesive—a Laboratory and Clinical Perspective

    PubMed Central

    Spotnitz, William D.

    2014-01-01

    Background. Fibrin sealant became the first modern era material approved as a hemostat in the United States in 1998. It is the only agent presently approved as a hemostat, sealant, and adhesive by the Food and Drug Administration (FDA). The product is now supplied as patches in addition to the original liquid formulations. Both laboratory and clinical uses of fibrin sealant continue to grow. The new literature on this material also continues to proliferate rapidly (approximately 200 papers/year). Methods. An overview of current fibrin sealant products and their approved uses and a comprehensive PubMed based review of the recent literature (February 2012, through March 2013) on the laboratory and clinical use of fibrin sealant are provided. Product information is organized into sections based on a classification system for commercially available materials. Publications are presented in sections based on both laboratory research and clinical topics are listed in order of decreasing frequency. Results. Fibrin sealant remains useful hemostat, sealant, and adhesive. New formulations and applications continue to be developed. Conclusions. This agent remains clinically important with the recent introduction of new commercially available products. Fibrin sealant has multiple new uses that should result in further improvements in patient care. PMID:24729902

  5. A multicentre, prospective, randomized, controlled trial comparing EVARREST™ fibrin sealant patch to standard of care in controlling bleeding following elective hepatectomy: anatomic versus non-anatomic resection

    PubMed Central

    Koea, Jonathan B.; Batiller, Jonathan; Aguirre, Nicolas; Shen, Jessica; Kocharian, Richard; Bochicchio, Grant; Garden, O. James

    2016-01-01

    Background This multicentre, randomized clinical trial assessed the safety and effectiveness of the EVARREST™ Fibrin Sealant Patch (FP) in treating parenchymal bleeding following anatomic and non-anatomic liver resections. Methods One hundred and two patients were stratified according to the type of hepatic resection (anatomic/non-anatomic), and randomized (1:1) after identification of an appropriate bleeding site, to FP vs Standard of Care (SoC, manual compression ± topical haemostat). The primary endpoint was haemostasis at 4 min from bleeding site identification with no re-bleeding requiring re-treatment. Results The FP was superior in achieving haemostasis at 4 min (96%, 48/50) to SoC (46%, 24/52; p < 0.001). Stratification for resection type showed treatment differences for primary endpoint for anatomic (24/25 FP vs 13/23 SoC; p = 0.001) and non-anatomic liver resections (24/25FP vs 11/29 SoC; p < 0.001). Adverse events related to the study procedure were reported in 40/50 patients (80%) in the FP group and 43/52 patients (83%) in the SoC group. One (2%) adverse event (infected intra-abdominal fluid collection) was possibly related to study treatment. Conclusion This clinical trial confirms that the FP is safe and highly effective in controlling parenchymal bleeding following hepatectomy regardless of the type of resection. ClinicalTrials.gov NCT01993888. PMID:27017161

  6. Efficacy and safety of fibrin sealant for tissue adherence in facial rhytidectomy

    PubMed Central

    Spotnitz, William D

    2012-01-01

    The purpose of this review is to clarify the present use of fibrin sealant in rhyditectomy procedures and help maximize the appropriate and safe application of this material. A set of terms and definitions for hemostats, sealants, and adhesives based on group, category, and class will be employed to highlight the specific capabilities of fibrin sealant. Fibrin sealant has now emerged as an example of maximizing the usefulness of a surgical agent and is the only product with Food and Drug Administration approval in all three groupings: hemostats; sealants; and adhesives. A variety of manufacturers’ fibrin sealant products are available including multiple liquids and one patch. A single liquid product is now specifically indicated for skin flap adherence during rhytidectomy. The unique characteristic of this particular two component fibrin sealant adhesive agent is its slower polymerization rate as a result of a low thrombin concentration which when combined with fibrinogen permits adequate time for manipulation of flaps and tissues prior to final fixation. In addition to its flap adherence and potential space elimination capability, fibrin sealant is also an excellent blood clotting agent and can seal tissues to prevent lymphatic leak or serous fluid accumulation. Thus, it is almost ideally suited to reduce the occurrence of fluid accumulation, hematomas, ecchymoses, and swelling, as well as to possibly eliminate the need for drains following rhytidectomy. A literature review of fibrin sealant in rhytidectomy is included to help define the current state of its clinical use. The author’s recommendations for the best use of this material during facial procedures are also provided. PMID:22791995

  7. Fibrin sealant use in pilonidal sinus: Systematic review.

    PubMed

    Kayaalp, Cuneyt; Ertugrul, Ismail; Tolan, Kerem; Sumer, Fatih

    2016-03-27

    To review the current data about the success rates of fibrin sealant use in pilonidal disease. Fibrin sealant can be used for different purposes in pilonidal sinus treatment, such as filling in the sinus tracts, covering the open wound after excision and lay-open treatment, or obliterating the subcutaneous dead space before skin closure. We searched Pubmed, Google-Scholar, Ebsco-Host, clinicaltrials, and Cochrane databases and found nine studies eligible for analysis; these studies included a total of 217 patients (84% male, mean age 24.2 ± 7.8). In cases where fibrin sealant was used to obliterate the subcutaneous dead space, there was no reduction in wound complication rates (9.8% vs 14.6%, P = 0.48). In cases where sealant was used to cover the laid-open area, the wound healing time and patient comfort were reported better than in previous studies (mean 17 d, 88% satisfaction). When fibrin sealant was used to fill the sinus tracts, the recurrence rate was around 20%, despite the highly selected grouping of patients. Consequently, using fibrin sealant to decrease the risk of seroma formation was determined to be an ineffective course of action. It was not advisable to fill the sinus tracts with fibrin sealant because it was not superior to other cost-effective and minimally invasive treatments. New comparative studies can be conducted to confirm the results of sealant use in covering the laid-open area.

  8. Nasal chondrocytes and fibrin sealant for cartilage tissue engineering.

    PubMed

    Vinatier, C; Gauthier, O; Masson, M; Malard, O; Moreau, A; Fellah, B H; Bilban, M; Spaethe, R; Daculsi, G; Guicheux, J

    2009-04-01

    Hybrid constructs associating a biodegradable matrix and autologous chondrocytes hold promise for the treatment of articular cartilage defects. In this context, our objective was to investigate the potential use of nasal chondrocytes associated with a fibrin sealant for the treatment of articular cartilage defects. The phenotype of primary nasal chondrocytes (NC) from human (HNC) and rabbit (RNC) origin were characterized by RT-PCR. The ability of constructs associating fibrin sealant and NC to form a cartilaginous tissue in vivo was investigated, firstly in a subcutaneous site in nude mice and secondly in an articular cartilage defect in rabbit. HNC express type II collagen and aggrecan, the two major hallmarks of a chondrocytic phenotype. Furthermore, when injected subcutaneously into nude mice within a fibrin sealant, these chondrocytes were able to form a cartilage-like tissue. Our data indicate that RNC also express type II collagen and aggrecan and maintained their phenotype in three-dimensional culture within a fibrin sealant. Moreover, treatment of rabbit articular cartilage defects with autologous RNC embedded in a fibrin sealant led to the formation of a hyalin-like repair tissue. The use of fibrin sealant containing hybrid autologous NC therefore appears as a promising approach for cell-based therapy of articular cartilage. Copyright 2008 Wiley Periodicals, Inc.

  9. Fibrin Sealants in Dura Sealing: A Systematic Literature Review.

    PubMed

    Esposito, Felice; Angileri, Filippo Flavio; Kruse, Peter; Cavallo, Luigi Maria; Solari, Domenico; Esposito, Vincenzo; Tomasello, Francesco; Cappabianca, Paolo

    2016-01-01

    Fibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks. A comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors. A total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or powered to demonstrate a

  10. Fibrin Sealants in Dura Sealing: A Systematic Literature Review

    PubMed Central

    2016-01-01

    Background Fibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks. Methods A comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors. Results A total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or

  11. Fibrin sealant fixation of a skin graft in mandibular vestibuloplasty. Case report.

    PubMed

    Yaman, Z

    1998-08-01

    Fibrin sealant fixation of a skin graft without the use of sutures or a stent in mandibular vestibuloplasty is presented in this case report. The advantages of the fibrin sealant in preprosthetic surgery are discussed.

  12. Fibrin sealant for management of complicated obstetric lacerations.

    PubMed

    Whiteside, James L; Asif, Rehan B; Novello, Renee J

    2010-02-01

    Fibrin sealant commonly is used topically for hemostasis in cardiovascular surgery. Complicated vulvar and vaginal bleeding after vaginal delivery can be difficult to manage using traditional techniques. A 21-year-old primipara, after a spontaneous vaginal delivery of a twin gestation, was found to have expanding right labial swelling and ecchymosis extending from the superior part of the labia majora to the ischial fossa that was approximately 10 cm wide. Surgical exploration was pursued, but poor tissue quality limited the effectiveness of traditional hemostatic techniques. Prompt hemostasis was achieved with application of fibrin sealant. Fibrin sealant may be useful for hemostasis when traditional techniques fail in complicated lacerations of the vulva and vagina associated with obstetric delivery.

  13. Hemostasis During Urologic Surgery: Fibrin Sealant Compared With Absorbable Hemostat

    PubMed Central

    Albala, David M; Riebman, Jerome B; Kocharian, Richard; Ilie, Bogdan; Albanese, John; Shen, Jessica; Ovington, Liza; Batiller, Jonathan

    2015-01-01

    In the United States, fibrin sealants have been used to achieve hemostasis for nearly two decades. Although their clinical utility was first demonstrated in cardiac surgery, their effectiveness and safety have since been demonstrated to extend to a wide array of procedures. Fibrin sealants typically contain two components—fibrinogen and thrombin—that are combined and delivered simultaneously to a target bleeding site in order to achieve hemostasis. However, many commercial formulations contain other additional components, such as antifibrinolytic agents, that have been associated with adverse outcomes. This subanalysis compares the safety and effectiveness of a fibrin sealant versus an absorbable hemostat for achieving hemostasis during urologic procedures with mild to moderate bleeding. PMID:26028998

  14. Efficacy of a fibrin sealant on healing of extraction wounds.

    PubMed

    Møller, J F; Petersen, J K

    1988-04-01

    In 61 patients, bilateral lower impacted third molars were removed. In 30 patients, a fibrin sealant was placed in the alveolus on one side immediately following the operation, while the other side functioned as control. In 31 patients, penicillin was added to the fibrin sealant, and the combination was placed in the alveolus on one side, the other side being the control. No difference with regard to bleeding, pain and swelling during the first postoperative week could be found. There was no difference between the sides regarding the incidence of postoperative infection and the healing of the alveoli after a 1-month control period.

  15. Fibrin sealant reduces pain after tonsillectomy: prospective randomized study.

    PubMed

    Vaiman, Michael; Krakovski, Daniel; Gavriel, Haim

    2006-07-01

    Postsurgical pain in adults following tonsillectomy with fibrin sealant or electrocoagulation was assessed by surface electromyography (sEMG), a dysphagia severity rating scale (DSRS), and a visual analog scale (VAS) pain For group 1 (n = 40), hemostasis was achieved by fibrin sealant spraying to the tonsillar fossae. For group 2 (n = 40), hemostasis was achieved by bipolar or needle point electrocautery. The timing of single swallowing and continuous drinking and the mean electrical activity of the masseter, infrahyoid, and submental-submandibular muscles were compared with a normative database during 30 days and with DSRS and VAS scores. Electrical activity of the masseter and infrahyoid muscles was significantly higher in both groups in comparison with the normative database (p < .05 to p < .005), whereas timing was less affected. The combined sEMG, DSRS, and VAS assessment showed that tonsillectomy ended with sealant causes less pain than electrocoagulation (p < .05). The DSRS score data were in strong positive correlation with the sEMG records, whereas the VAS pain score was less informative. The combined sEMG and pain score data indicate that the electrocautery hemostatic technique is more painful and traumatic than the sealant technique. Surface electromyography of swallowing is a simple, reliable evaluation method for postsurgical odynophagia complaints and might be used as an objective tool for pain assessment.

  16. Does Fibrin Sealant Reduce Seroma after Immediate Breast Reconstruction Utilizing a Latissimus Dorsi Myocutaneous Flap?

    PubMed Central

    Cha, Han Gyu; Shin, Ho Seong; Kang, Moon Seok; Nam, Seung Min

    2012-01-01

    Background The most common complication of latissimus dorsi myocutaneous flap in breast reconstruction is seroma formation in the back. Many clinical studies have shown that fibrin sealant reduces seroma formation. We investigated any statistically significant differences in postoperative drainage and seroma formation when utilizing the fibrin sealant on the site of the latissimus dorsi myocutaneous flap harvested for immediate breast reconstruction after skin-sparing partial mastectomy. Methods A total of 46 patients underwent immediate breast reconstruction utilizing a latissimus dorsi myocutaneous island flap. Of those, 23 patients underwent the procedure without fibrin sealant and the other 23 were administered the fibrin sealant. All flaps were elevated with manual dissection by the same surgeon and were analyzed to evaluate the potential benefits of the fibrin sealant. The correlation analysis and Mann-Whitney U test were used for analyzing the drainage volume according to age, weight of the breast specimen, and body mass index. Results Although not statistically significant, the cumulative drainage fluid volume was higher in the control group until postoperative day 2 (530.1 mL compared to 502.3 mL), but the fibrin sealant group showed more drainage beginning on postoperative day 3. The donor site comparisons showed the fibrin sealant group had more drainage beginning on postoperative day 3 and the drain was removed 1 day earlier in the control group. Conclusions The use of fibrin sealant resulted in no reduction of seroma formation. Because the benefits of the fibrin sealant are not clear, the use of fibrin sealant must be fully discussed with patients before its use as a part of informed consent. PMID:23094246

  17. Venous gas embolism caused by fibrin sealant application to the prostate during greenlight laser photoselective vaporization.

    PubMed

    Lee, Alexander; Vazquez, Rafael

    2015-04-15

    Venous gas embolism is a complication of fibrin sealant application and is a well-described event during various modes of prostate resection. We describe the case of a nitrogen venous gas embolism during Greenlight laser photovaporization of the prostate during the application of fibrin sealant to the operative site for hemostasis. Fibrin sealant application by a compressed gas applicator is a cause of venous air embolism, and this case highlights the need to keep venous gas embolism in mind when compressed gas applicators are used.

  18. A new fibrin sealant as a three-dimensional scaffold candidate for mesenchymal stem cells

    PubMed Central

    2014-01-01

    Introduction The optimization of an organic scaffold for specific types of applications and cells is vital to successful tissue engineering. In this study, we investigated the effects of a new fibrin sealant derived from snake venom as a scaffold for mesenchymal stem cells, to demonstrate the ability of cells to affect and detect the biological microenvironment. Methods The characterization of CD34, CD44 and CD90 expression on mesenchymal stem cells was performed by flow cytometry. In vitro growth and cell viability were evaluated by light and electron microscopy. Differentiation into osteogenic, adipogenic and chondrogenic lineages was induced. Results The fibrin sealant did not affect cell adhesion, proliferation or differentiation and allowed the adherence and growth of mesenchymal stem cells on its surface. Hoechst 33342 and propidium iodide staining demonstrated the viability of mesenchymal stem cells in contact with the fibrin sealant and the ability of the biomaterial to maintain cell survival. Conclusions The new fibrin sealant is a three-dimensional scaffolding candidate that is capable of maintaining cell survival without interfering with differentiation, and might also be useful in drug delivery. Fibrin sealant has a low production cost, does not transmit infectious diseases from human blood and has properties of a suitable scaffold for stem cells because it permits the preparation of differentiated scaffolds that are suitable for every need. PMID:24916098

  19. Effect of intracameral injection of fibrin tissue sealant on the rabbit anterior segment

    PubMed Central

    Chew, Annabel C.Y.; Tan, Donald T.H.; Poh, Rebekah; HM, Htoon; Beuerman, Roger W.

    2010-01-01

    Purpose To investigate the effect of intracameral injection of fibrin tissue sealant on the anterior segment structures in a rabbit model. Methods One eye of 10 rabbits received an intracameral injection of fibrin tissue sealant with a thrombin concentration of 500 IU (TISSEEL), and the fellow eye received an intracameral injection of balanced salt solution as a control. The rabbits were followed up with serial slit-lamp examinations, photography, high resolution anterior segment optical coherence tomography scans with pachymetry measurement, and intraocular pressure (IOP) monitoring until complete dissolution of the fibrin sealant. Corneal endothelial cell viability was evaluated using live/dead cell assays. Apoptosis of the cornea and trabecular meshwork were evaluated using TUNEL assays. Ultra-structural examinations of the cornea and trabecular meshwork were performed using electron microscopy. Histology of the trabecular meshwork and iris were analyzed using light microscopy. Results The quantity of the intracameral fibrin sealant was shown to be significantly correlated with increased IOP and pachymetry post-operatively. Complete dissolution of the fibrin sealant occurred between 15 and 30 days. Live/dead cell assays showed no decrease in viability of the corneal endothelium, and TUNEL assays showed no increase in apoptosis of the corneal epithelium, stroma, endothelium, or trabecular meshwork in the eyes with the fibrin sealant. Light and electron microscopy of the anterior segment structures were unremarkable. Conclusion The intracameral use of fibrin glue was associated with a transient increase in IOP and pachymetry. However, there was no evidence of toxicity or structural damage to the corneal endothelium, trabecular meshwork, or iris. PMID:20596250

  20. Fibrin Sealant: A Review of the History, Biomechanics, and Current Applications for Prosthetic Fixation in Hernia Repair.

    PubMed

    Watson, Jefferson Tyler; Webb, David L; Stoikes, Nathaniel F N; Voeller, Guy R

    2015-11-01

    The role of surgical adhesives in hernia repair has continued to evolve. The purpose of this chapter is to review the role of fibrin sealant and its application in general surgery for mesh fixation, specifically the history, biomechanics, and clinical utilization. The utilization of fibrin sealant for repair of groin hernias, both open and laparoscopic, ventral hernias, and hiatal hernias will be discussed.

  1. Endoscopic fibrin sealant closure of duodenal perforation after endoscopic retrograde cholangiopancreatography.

    PubMed

    Yang, Hsin-Yeh; Chen, Jui-Hao

    2015-12-07

    Traditionally, perivaterian duodenal perforation can be managed conservatively or surgically. If a large volume of leakage results in fluid collection in the retroperitoneum, surgery may be necessary. Our case met the surgical indication for perivaterian duodenal perforation after endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy and endoscopic papillary balloon dilatation. The patient developed a retroperitoneal abscess after the procedures, and a perivaterian perforation was suggested on computed tomography (CT). CT-guided abscess drainage was performed immediately. We unsuccessfully attempted to close the perforation with hemoclips initially. Subsequently, we used fibrin sealant (Tisseel) injection to occlude the perforation. Fibrin sealant injections have been previously used during endoscopy for wound closure and fistula repair. Based on our report, fibrin sealant injection can be considered as an alternative method for the treatment of ERCP-related type II perforations.

  2. Application of Fibrin Glue Sealant After Hepatectomy Does Not Seem Justified

    PubMed Central

    Figueras, Juan; Llado, Laura; Miro, Mónica; Ramos, Emilio; Torras, Jaume; Fabregat, Juan; Serrano, Teresa

    2007-01-01

    Objective: To evaluate the efficacy, amount of hemorrhage, biliary leakage, complications, and postoperative evolution after fibrin glue sealant application in patients undergoing liver resection. Summary Background Data: Fibrin sealants have become popular as a means of improving perioperative hemostasis and reducing biliary leakage after liver surgery. However, trials regarding its use in liver surgery remain limited and of poor methodologic quality. Patients and Methods: A total of 300 patients undergoing hepatic resection were randomly assigned to fibrin glue application or control groups. Characteristics and debit of drainage and postoperative complications were evaluated. The amount of blood loss, measurements of hematologic parameters liver test, and postoperative evolution (particularly involving biliary fistula and morbidity) was also recorded. Results: Postoperatively, no differences were observed in the amount of transfusion (0.15 ± 0.66 vs. 0.17 ± 0.63 PRCU; P = 0.7234) or in the patients that required transfusion (18% vs. 12%; P = 0.2), respectively, for the fibrin glue or control group. There were no differences in overall drainage volumes (1180 ± 2528 vs. 960 ± 1253 mL) or in days of postoperative drainage (7.9 ± 5 vs. 7.1 ± 4.7). Incidence of biliary fistula was similar in the fibrin glue and control groups, (10% vs. 11%). There were no differences regarding postoperative morbidity between groups (23% vs. 23%; P = 1). Conclusions: Application of fibrin sealant in the raw surface of the liver does not seem justified. Blood loss, transfusion, incidence of biliary fistula, and outcome are comparable to patients without fibrin glue. Therefore, discontinuation of routine use of fibrin sealant would result in significant cost saving. PMID:17414601

  3. The Use Fibrin Sealant after Spinal Intradural Tumor Surgery: Is It Necessary?

    PubMed Central

    Won, Young Il; Chung, Chun Kee; Jahng, Tae-Ahn; Park, Sung Bae

    2016-01-01

    Objective A fibrin sealant is commonly applied after closure of an incidental or intended durotomy to reduce the complications associated with the leakage of cerebrospinal fluid. Routine usage might not be essential after closure of an intended durotomy, which has clear cut-margins. We investigated the efficacy of fibrin sealants for primary intradural spinal cord tumor surgery. Methods A retrospective review was performed for 231 consecutive surgically treated patients with primary intradural spinal cord tumors without extradural extension. Fibrin sealants were not used for 47 patients (group I: age, 51.57±16.75 years) and were applied to 184 patients (group II: age, 48.8±14.7 years). The surgical procedures were identical except for the use of a fibrin sealant after closure of the durotomy. The primary outcome was the occurrence of complications (wound problems, hematoma collection, infection, and neurological deterioration). The covariates were age, sex, body mass index, operation time, pre-/postoperative ambulation, number of laminectomies, and type of tumor. Results Schwannoma was the most common pathology (n=134), followed by meningioma (n=35) and ependymoma (n=31). Complications occurred in 13 patients (3 in group I and 10 in group II, p=0.73). The postoperative ambulation status (p<0.01; odds ratio, 28.8; 95% confidence interval, 6.9-120.0) and operation time (p=0.04; cutoff, 229 minutes; sensitivity, 62%; specificity, 72%) were significant factors, whereas the use of a fibrin glue was not (p=0.47). Conclusion The use of a fibrin sealant might not be essential to reduce complications after surgery for primary spinal intradural tumor. PMID:27123027

  4. Long-Standing Motor and Sensory Recovery following Acute Fibrin Sealant Based Neonatal Sciatic Nerve Repair

    PubMed Central

    Ferreira Junior, Rui Seabra

    2016-01-01

    Brachial plexus lesion results in loss of motor and sensory function, being more harmful in the neonate. Therefore, this study evaluated neuroprotection and regeneration after neonatal peripheral nerve coaptation with fibrin sealant. Thus, P2 neonatal Lewis rats were divided into three groups: AX: sciatic nerve axotomy (SNA) without treatment; AX+FS: SNA followed by end-to-end coaptation with fibrin sealant derived from snake venom; AX+CFS: SNA followed by end-to-end coaptation with commercial fibrin sealant. Results were analyzed 4, 8, and 12 weeks after lesion. Astrogliosis, microglial reaction, and synapse preservation were evaluated by immunohistochemistry. Neuronal survival, axonal regeneration, and ultrastructural changes at ventral spinal cord were also investigated. Sensory-motor recovery was behaviorally studied. Coaptation preserved synaptic covering on lesioned motoneurons and led to neuronal survival. Reactive gliosis and microglial reaction decreased in the same groups (AX+FS, AX+CFS) at 4 weeks. Regarding axonal regeneration, coaptation allowed recovery of greater number of myelinated fibers, with improved morphometric parameters. Preservation of inhibitory synaptic terminals was accompanied by significant improvement in the motor as well as in the nociceptive recovery. Overall, the present data suggest that acute repair of neonatal peripheral nerves with fibrin sealant results in neuroprotection and regeneration of motor and sensory axons. PMID:27446617

  5. High-Pressure Fibrin Sealant Foam: An Effective Hemostatic Agent for Treating Severe Parenchymal Hemorrhage

    DTIC Science & Technology

    2008-01-01

    least 7 days and carefully checked for any preexisting disease before undergoing surgical procedures. The daily food was withdrawn from the surgical...2003;237:871; discussion 876. 31. Jakob H, Campbell CD, Qiu ZK , et al. Use of fibrin sealant for reinforcing arterial anastomoses. J Vasc Surg 1984;1:171

  6. Fibrin sealant prevents gastrointestinal anastomosis dehiscence in intra-abdominal sepsis.

    PubMed

    Wang, Xinbo; Ren, Jianan; Zhu, Weiming; Li, Ning; Li, Jieshou

    2007-01-01

    We observed the potential use of fibrin sealant as a therapeutic modality for successful resolution of gastrointestinal anastomosis dehiscence in intra-abdominal sepsis. Forty-eight patients (33 men and 15 women) suffering from intra-abdominal sepsis were subjected to prophylactic appliance of fibrin sealant during immediate primary anastomosis during the laparotomy. The perioperative management invariably involved fluid resuscitation, active suction drainage of the abdominal liquor puris, nutritional supplementation, and growth hormone. The total surgical-related success ratio was 91.7% (44/48) for primary anastomosis with fibrin sealant in intra-abdominal sepsis. Anastomotic leakage occurred in the other four patients, two of which died because of leakage complications in our hospital. The hospital stay after the operation was 30.2 +/- 12.0 days. There has been no sign of recurrence over a follow-up period of 1-15 months. It is concluded that fibrin sealant may be useful in preventing gastrointestinal anastomosis dehiscence in intra-abdominal sepsis.

  7. Use of autologous fibrin sealants to treat ganglion cysts: a report of two cases.

    PubMed

    Nakama, Kenjiro; Gotoh, Masafumi; Mitsui, Yasuhiro; Shirachi, Isao; Higuchi, Fujio; Nagata, Kensei

    2010-04-01

    Two patients underwent arthroscopy-guided injections of autologous fibrin sealants to treat ganglion cysts causing suprascapular nerve palsies. After at least 2 years of follow-up, both patients had no suprascapular nerve symptoms and their external rotation strength had returned to normal. Magnetic resonance imaging revealed no evidence of ganglion cyst recurrence.

  8. Fibrin sealant improves graft adherence in a porcine full-thickness burn wound model.

    PubMed

    Branski, Ludwik K; Mittermayr, Rainer; Herndon, David N; Jeschke, Marc G; Hofmann, Martina; Masters, Oscar E; Norbury, William B; Traber, Daniel L; Tangl, Stefan; Redl, Heinz

    2011-12-01

    Autograft take and rapid wound closure is essential for the survival of severely burned patients. Loss of skin grafts typically occurs during the first few days after coverage, mainly due to shear forces and inadequate contact with the wound bed. Slow-clotting fibrin sealant, applied with a spray-on device, has been shown to improve healing of skin grafts in large wounds. However, its use in burn wounds has not been studied so far. To evaluate the effectiveness of sprayed fibrin sealant in excised and grafted full-thickness burns. Ten female Yorkshire pigs (30-45 kg) received a full-thickness contact burn of approximately 15% total body surface area. The burns were excised to the level of the muscular fascia after 24 h and covered with meshed skin autograft (mesh ratio 1:3). Wounds were randomized to either fibrin sealant (n=20) or standard skin staples (n=16) for graft fixation. Fibrin sealant was used as a slow-clotting spray (4 IU thrombin/ml). Outcome measurements included clinical scoring at days 2, 5, 9 and 14 postoperatively, planimetric analysis of wound closure, and histological examination of epidermal and dermal thickness 14 days after autografting. In the fibrin sealant group, graft adherence scores were significantly increased (p<0.02) and graft dislocation scores significantly decreased (p<0.01) at days 2 and 5 postoperatively, when compared to controls. Planimetric analysis of remaining open mesh interstices showed acceleration of wound closure in the fibrin sealant group but did not reach statistical significance (day 14 p=0.04 at significance level p<0.025). Wound contraction, occurrence of hematoma, and dermal as well as epidermal thickness were not different between the groups at 14 days postoperatively. The results indicate that the use of slow-clotting fibrin sealant spray for autograft fixation is advantageous over skin staples. Easy handling and reduced graft dislocation at early time points are key qualities of this method. Copyright © 2011

  9. MBCP biphasic calcium phosphate granules and tissucol fibrin sealant in rabbit femoral defects: the effect of fibrin on bone ingrowth.

    PubMed

    Le Guehennec, Laurent; Goyenvalle, Eric; Aguado, Eric; Pilet, Paul; Bagot D'Arc, Maurice; Bilban, Melitta; Spaethe, Reiner; Daculsi, Guy

    2005-01-01

    An ageing population implies an increase in bone and dental diseases, which are in turn a source of numerous handicaps. These pathologies are an expensive burden for the European health system. As no specific bioactive materials are efficient enough to cope with this burden, we have to develop an injectable, mouldable, self-hardening bone substitute to support bone tissue reconstruction and augmentation. New, highly bioactive and suitable biomaterials have been developed to replace bone grafts in orthopedic revision and maxillofacial surgery for bone augmentation. These mouldable, self-hardening materials are based on the association of MBCP Biphasic Calcium Phosphate Granules and Tissucol Fibrin Sealant. The in vivo evaluation of ingrowth in relation to the composite was made in an experiment on rabbits. The results indicate that in the presence of fibrin sealant, newly-formed bone developed at a small distance from the surface of the calcium phosphate ceramic. Two different bone apposition processes were identified. Without the fibrin component (MBCP group), bone rested directly on the surface of the granules. This observation is commonly described as osteoconduction in calcium phosphate materials. On the contrary, the presence of the fibrinogen component seemed to modify this standard osteoconduction phenomenon: the newly-formed bone essentially grew at a distance from the surface of the granules, on the fibrillar network, and could be considered as an inductive phenomenon for osteogenic cell differentiation from mesenchymal stem cells.

  10. Treatment of post-prostatectomy rectourethral fistula with fibrin sealant (Quixil™) injection: a novel application.

    PubMed

    Verriello, V; Altomare, M; Masiello, G; Curatolo, C; Balacco, G; Altomare, D F

    2010-12-01

    Rectourethral fistulas in adults is a rare but potentially devastating postoperative condition requiring complex and demanding surgery. Fibrin glue treatment has been used with some success in anal and rectovaginal fistulas, and in the case we present here this indication has been extended to a postoperative rectourethral fistula following radical prostatectomy. For the first time, to our knowledge, a fibrin sealant (Quixil) was injected into the fistula tract, and a rectal mucosal flap was used to close the internal opening. The fistula healed in few weeks, and the patient is symptom free after 1 year of follow-up.

  11. Internal Iliac Artery Aneurysm Embolization with Fibrin Sealant: A Simple and Effective Solution

    SciTech Connect

    Brountzos, Elias N.; Malagari, Katerina; Papathanasiou, Mathildi A.; Gougoulakis, Alexandros; Kelekis, Dimitrios A.

    2003-02-15

    Endovascular treatment of internal iliac artery (IIA) aneurysms is an attractive alternative to surgical management, because the former is associated with less morbidity and mortality.Embolization with coils or exclusion of the IIA orifice with stent -grafts are the preferred techniques. Although uncommon, technical failures occur with reported aneurysm rupture. Two patients with IIA aneurysms are reported here, where we describe successful occlusion of their IIA aneurysms with the use of fibrin sealant, after initial failure of coil embolization.

  12. Laparoscopic Repair of Inguinal Hernia Using Surgisis Mesh and Fibrin Sealant

    PubMed Central

    2006-01-01

    Objective: We tested the hypothesis that laparoscopic inguinal herniorrhaphy using Surgisis mesh secured with fibrin sealant is an effective long-term treatment for repair of inguinal hernia. This case series involved 38 adult patients with 51 inguinal hernias treated in a primary care center. Methods: Between December 2002 and May 2005, 38 patients with 45 primary and 6 recurrent inguinal hernias were treated with laparoscopic repair by the total extra-peritoneal mesh placement (TEP) technique using Surgisis mesh secured into place with fibrin sealant. Postoperative complications, incidence of pain, and recurrence were recorded, as evaluated at 2 weeks, 6 weeks, 1 year, and with a follow-up questionnaire and telephone interview conducted in May and June 2005. Results: The operations were successfully performed on all patients with no complications or revisions to an open procedure. Average follow-up was 13 months (range, 1 to 30). One hernia recurred (second recurrence of unilateral direct hernia), indicating a 2% recurrence rate. Conclusions: Laparoscopic repair of inguinal hernia using Surgisis mesh secured with fibrin sealant can be effectively used to treat primary, recurrent, direct, indirect, and bilateral inguinal hernias in adults without complications and minimal recurrence within 1-year of follow-up. PMID:17575758

  13. Reduction of the closure time of postoperative enterocutaneous fistulas with fibrin sealant

    PubMed Central

    Avalos-González, Jorge; Portilla-deBuen, Eliseo; Leal-Cortés, Caridad Aurea; Orozco-Mosqueda, Abel; del Carmen Estrada-Aguilar, María; Velázquez-Ramírez, Gabriela Abigail; Ambriz-González, Gabriela; Fuentes-Orozco, Clotilde; Guzmán-Gurrola, Aldo Emmerson; González-Ojeda, Alejandro

    2010-01-01

    AIM: To assess whether the use of fibrin sealant shortens the closure time of postoperative enterocutaneous fistulas (ECFs). METHODS: The prospective case-control study included 70 patients with postoperative ECFs with an output of < 500 mL/d, a fistulous tract of > 2 cm and without any local complication. They were divided into study (n = 23) and control groups (n = 47). Esophageal, gastric and colocutaneous fistulas were monitored under endoscopic visualization, which also allowed fibrin glue application directly through the external hole. Outcome variables included closure time, time to resume oral feeding and morbidity related to nutritional support. RESULTS: There were no differences in mean age, fistula output, and follow-up. Closure-time for all patients of the study group was 12.5 ± 14.2 d and 32.5 ± 17.9 d for the control group (P < 0.001), and morbidity related to nutritional support was 8.6% and 42.5%, respectively (P < 0.01). In patients with colonic fistulas, complete closure occurred 23.5 ± 19.5 d after the first application of fibrin glue, and spontaneous closure was observed after 36.2 ± 22.8 d in the control group (P = 0.36). Recurrences were observed in 2 patients because of residual disease. One patient of each group died during follow-up as a consequence of septic complications related to parenteral nutrition. CONCLUSION: Closure time was significantly reduced with the use of fibrin sealant, and oral feeding was resumed faster. We suggest the use of fibrin sealant for the management of stable enterocutaneous fistulas. PMID:20533600

  14. Anaphylactic reaction after systemic application of aprotinin triggered by aprotinin-containing fibrin sealant.

    PubMed

    Kober, Benjamin J; Scheule, Albertus M; Voth, Vladimir; Deschner, Norbert; Schmid, Eckhard; Ziemer, Gerhard

    2008-08-01

    We report a 67-yr-old male after multiple surgical procedures for treatment of arterial occlusive disease who suffered an anaphylactic reaction after administration of aprotinin (Trasylol) prior to urgent coronary artery bypass surgery. The patient had been treated with aprotinin-containing fibrin sealant in 2004 and in 2007, 2 wk before coronary artery bypass surgery. The postoperative serologic screening revealed positive results for qualitative aprotinin-specific IgG, highly elevated quantitative aprotinin-specific IgG and moderately elevated aprotinin-specific IgE antibodies.

  15. A new heterologous fibrin sealant as a scaffold to cartilage repair—Experimental study and preliminary results

    PubMed Central

    de Barros, Caio Nunes; Miluzzi Yamada, Ana Lúcia; Junior, Rui Seabra F; Barraviera, Benedito; Hussni, Carlos Alberto; de Souza, Jaqueline Brandão; Watanabe, Marcos Jun; Rodrigues, Celso Antônio

    2015-01-01

    Autologous fibrin gel is commonly used as a scaffold for filling defects in articular cartilage. This biomaterial can also be used as a sealant to control small hemorrhages and is especially helpful in situations where tissue reparation capacity is limited. In particular, fibrin can act as a scaffold for various cell types because it can accommodate cell migration, differentiation, and proliferation. Despite knowledge of the advantages of this biomaterial and mastery of the techniques required for its application, the durability of several types of sealant at the site of injury remains questionable. Due to the importance of such data for evaluating the quality and efficiency of fibrin gel formulations on its use as a scaffold, this study sought to analyze the heterologous fibrin sealant developed from the venom of Crotalus durissus terrificus using studies in ovine experimental models. The fibrin gel developed from the venom of this snake was shown to act as a safe, stable, and durable scaffold for up to seven days, without causing adverse side effects. Fibrin gel produced from the venom of the Crotalus durissus terrificus snake possesses many clinical and surgical uses. It presents the potential to be used as a biomaterial to help repair skin lesions or control bleeding, and it may also be used as a scaffold when applied together with various cell types. The intralesional use of the fibrin gel from the venom of this snake may improve surgical and clinical treatments in addition to being inexpensive and adequately consistent, durable, and stable. The new heterologous fibrin sealant is a scaffold candidate to cartilage repair in this study. PMID:26264444

  16. New techniques in the treatment of common perianal diseases: stapled hemorrhoidopexy, botulinum toxin, and fibrin sealant.

    PubMed

    Singer, Marc; Cintron, Jose

    2006-08-01

    There have been several recent advances in the treatment of common perianal diseases. Stapled hemorrhoidopexy is a procedure of hemorrhoidal fixation, combining the benefits of rubber band ligation into an operative technique. The treatment of anal fissure has typically relied upon internal sphincterotomy; however, it carries a risk of incontinence. The injection of botulinum toxin represents a new form of sphincter relaxation, without division of any sphincter muscle; morbidity is minimal and results are promising. For the treatment of fistula in a fistulotomy remains the gold standard, however, it carries significant risk of incontinence. Use of fibrin sealant to treat fistulae has been met with variable success. It offers sealing of the tract, and then provides scaffolding for native tissue ingrowth.

  17. Direct Spinal Ventral Root Repair following Avulsion: Effectiveness of a New Heterologous Fibrin Sealant on Motoneuron Survival and Regeneration

    PubMed Central

    Barbizan, Roberta; Seabra Ferreira, Rui

    2016-01-01

    Axonal injuries at the interface between central and peripheral nervous system, such as ventral root avulsion (VRA), induce important degenerative processes, mostly resulting in neuronal and motor function loss. In the present work, we have compared two different fibrin sealants, one derived from human blood and another derived from animal blood and Crotalus durissus terrificus venom, as a promising treatment for this type of injury. Lewis rats were submitted to VRA (L4–L6) and had the avulsed roots reimplanted to the surface of the spinal cord, with the aid of fibrin sealant. The spinal cords were processed to evaluate neuronal survival, synaptic stability, and glial reactivity, 4 and 12 weeks after lesion. Sciatic nerves were processed to investigate Schwann cell activity by p75NTR expression (4 weeks after surgery) and to count myelinated axons and morphometric evaluation (12 weeks after surgery). Walking track test was used to evaluate gait recovery, up to 12 weeks. The results indicate that both fibrin sealants are similarly efficient. However, the snake-derived fibrin glue is a potentially safer alternative for being a biological and biodegradable product which does not contain human blood derivatives. Therefore, the venom glue can be a useful tool for the scientific community due to its advantages and variety of applications. PMID:27642524

  18. Characterization of mechanics and cytocompatibility of fibrin-genipin annulus fibrosus sealant with the addition of cell adhesion molecules.

    PubMed

    Guterl, Clare C; Torre, Olivia M; Purmessur, Devina; Dave, Khyati; Likhitpanichkul, Morakot; Hecht, Andrew C; Nicoll, Steven B; Iatridis, James C

    2014-09-01

    There is an unmet clinical need for a biomaterial sealant capable of repairing small annulus fibrosus (AF) defects. Causes of these defects include painful intervertebral disc herniations, microdiscectomy procedures, morbidity associated with needle puncture injury from discography, and future nucleus replacement procedures. This study describes the enhancements of a fibrin gel through genipin crosslinking (FibGen) and the addition of the cell adhesion molecules (CAMs), fibronectin and collagen. The gel's performance as a potential AF sealant is assessed using a series of in vitro tests. FibGen gels with CAMs had equivalent adhesive strength, gene expression, cytomorphology, and cell proliferation as fibrin alone. However, FibGen gels had enhanced material behaviors that were tunable to higher shear stiffness values and approximated human annulus tissue as compared with fibrin alone, were more dimensionally stable, and had a slower in vitro degradation rate. Cytomorphology of human AF cells cultured on FibGen gels exhibited increased elongation compared with fibrin alone, and the addition of CAMs to FibGen did not significantly affect elongation. This FibGen gel offers the promise of being used as a sealant material to repair small AF defects or to be used in combination with other biomaterials as an adhesive for larger defects.

  19. Characterization of Mechanics and Cytocompatibility of Fibrin-Genipin Annulus Fibrosus Sealant with the Addition of Cell Adhesion Molecules

    PubMed Central

    Guterl, Clare C.; Torre, Olivia M.; Purmessur, Devina; Dave, Khyati; Likhitpanichkul, Morakot; Hecht, Andrew C.; Nicoll, Steven B.

    2014-01-01

    There is an unmet clinical need for a biomaterial sealant capable of repairing small annulus fibrosus (AF) defects. Causes of these defects include painful intervertebral disc herniations, microdiscectomy procedures, morbidity associated with needle puncture injury from discography, and future nucleus replacement procedures. This study describes the enhancements of a fibrin gel through genipin crosslinking (FibGen) and the addition of the cell adhesion molecules (CAMs), fibronectin and collagen. The gel's performance as a potential AF sealant is assessed using a series of in vitro tests. FibGen gels with CAMs had equivalent adhesive strength, gene expression, cytomorphology, and cell proliferation as fibrin alone. However, FibGen gels had enhanced material behaviors that were tunable to higher shear stiffness values and approximated human annulus tissue as compared with fibrin alone, were more dimensionally stable, and had a slower in vitro degradation rate. Cytomorphology of human AF cells cultured on FibGen gels exhibited increased elongation compared with fibrin alone, and the addition of CAMs to FibGen did not significantly affect elongation. This FibGen gel offers the promise of being used as a sealant material to repair small AF defects or to be used in combination with other biomaterials as an adhesive for larger defects. PMID:24684314

  20. Motor recovery and synaptic preservation after ventral root avulsion and repair with a fibrin sealant derived from snake venom.

    PubMed

    Barbizan, Roberta; Castro, Mateus V; Rodrigues, Antônio C; Barraviera, Benedito; Ferreira, Rui S; Oliveira, Alexandre L R

    2013-01-01

    Ventral root avulsion is an experimental model of proximal axonal injury at the central/peripheral nervous system interface that results in paralysis and poor clinical outcome after restorative surgery. Root reimplantation may decrease neuronal degeneration in such cases. We describe the use of a snake venom-derived fibrin sealant during surgical reconnection of avulsed roots at the spinal cord surface. The present work investigates the effects of this fibrin sealant on functional recovery, neuronal survival, synaptic plasticity, and glial reaction in the spinal motoneuron microenvironment after ventral root reimplantation. Female Lewis rats (7 weeks old) were subjected to VRA and root replantation. The animals were divided into two groups: 1) avulsion only and 2) replanted roots with fibrin sealant derived from snake venom. Post-surgical motor performance was evaluated using the CatWalk system twice a week for 12 weeks. The rats were sacrificed 12 weeks after surgery, and their lumbar intumescences were processed for motoneuron counting and immunohistochemistry (GFAP, Iba-1 and synaptophysin antisera). Array based qRT-PCR was used to evaluate gene regulation of several neurotrophic factors and receptors as well as inflammatory related molecules. The results indicated that the root reimplantation with fibrin sealant enhanced motor recovery, preserved the synaptic covering of the motoneurons and improved neuronal survival. The replanted group did not show significant changes in microglial response compared to VRA-only. However, the astroglial reaction was significantly reduced in this group. In conclusion, the present data suggest that the repair of avulsed roots with snake venom fibrin glue at the exact point of detachment results in neuroprotection and preservation of the synaptic network at the microenvironment of the lesioned motoneurons. Also such procedure reduced the astroglial reaction and increased mRNA levels to neurotrophins and anti

  1. Use of a Thrombin Fibrin Sealant in Reducing Blood Loss in Revision Hip Arthroplasty

    PubMed Central

    Ghoz, Ali; Al-Khateeb, Hesham; Rajkumar, Shanmugasundaram; Tavares, Shawn; Andrade, Antonio

    2015-01-01

    We present a retrospective evaluation assessing the use of a novel fibrin sealant, Quixil® (OMRIX Biopharmaceuticals S.A.) in reducing blood transfusions following revision total hip replacement surgery. Forty four patients underwent revision total hip replacement surgery using Quixil®, while 45 patients underwent revision total hip replacement surgery without the use of Quixil®. The duration of surgery and patient demographics were similar in both groups. Average blood loss was 1,010ml in the Quixil® group versus 1,021ml in the non-Quixil group. The use of cell saver and intra-operative blood transfusion were similar in both groups. The mean pre-operative Haemoglobin was 13.0 g/dl in the Quixil® group versus 12.4 g/dl in the non-Quixil group. The mean post-operative haemoglobin was 10.2 g/dl and 9.1 g/dl in the Quixil® and non-Quixil groups respectively. There was no difference in the blood transfused post-operatively between the two groups. Total units of blood transfused in Quixil® versus non-Quixil group were 60 verus 86. Total units of intra-operative blood transfused in Quixil® versus non-Quixil group were 16 versus 23. The use of fibrin tissue adhesive in revision total hip arthroplasty seems to be an effective and reliable means to reduce blood-transfusion requirements and prevent post-operative decreases in hemoglobin. PMID:27468998

  2. Fibrin sealants from fresh or fresh/frozen plasma as scaffolds for in vitro articular cartilage regeneration.

    PubMed

    Dare, Emma V; Griffith, May; Poitras, Philippe; Wang, Tao; Dervin, Geoffrey F; Giulivi, Antonio; Hincke, Maxwell T

    2009-08-01

    Our objective was to evaluate human CryoSeal fibrin glue derived from single units of plasma as scaffolds for articular cartilage tissue engineering. Human articular chondrocytes were encapsulated into genipin cross-linked fibrin glue derived from individual units of fresh or frozen plasma using the CryoSeal fibrin sealant (FS) system. The constructs were cultured for up to 7 weeks in vitro under low (5%) or normal (21%) oxygen. Chondrocyte viability was >90% within the fibrin gels. Hypoxia induced significant increases in collagen II and Sox9 gene expression and a significant decrease in collagen I. A significant increase in collagen II was detected in fresh plasma-derived cultures, while only collagen I was significantly increased in frozen plasma cultures. Significant increases in total glycosaminoglycan and collagen were detected in the extracellular matrix secreted by the encapsulated chondrocytes. A significant increase in compression modulus was only observed for fresh plasma-derived gels, which is likely explained by a greater amount of collagen type I detected after 7 weeks in frozen compared to fresh plasma gels. Our results indicate that CryoSeal fibrin glue derived from fresh plasma is suitable as a tissue engineering scaffold for human articular chondrocytes, and therefore should be evaluated for autologous articular cartilage regeneration.

  3. The use of fibrin sealant during non-emergency surgery: a systematic review of evidence of benefits and harms.

    PubMed Central

    Edwards, Steven J; Crawford, Fay; van Velthoven, Michelle Helena; Berardi, Andrea; Osei-Assibey, George; Bacelar, Mariana; Salih, Fatima; Wakefield, Victoria

    2016-01-01

    BACKGROUND Fibrin sealants are used in different types of surgery to prevent the accumulation of post-operative fluid (seroma) or blood (haematoma) or to arrest haemorrhage (bleeding). However, there is uncertainty around the benefits and harms of fibrin sealant use. OBJECTIVES To systematically review the evidence on the benefits and harms of fibrin sealants in non-emergency surgery in adults. DATA SOURCES Electronic databases [MEDLINE, EMBASE and The Cochrane Library (including the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, the Health Technology Assessment database and the Cochrane Central Register of Controlled Trials)] were searched from inception to May 2015. The websites of regulatory bodies (the Medicines and Healthcare products Regulatory Agency, the European Medicines Agency and the Food and Drug Administration) were also searched to identify evidence of harms. REVIEW METHODS This review included randomised controlled trials (RCTs) and observational studies using any type of fibrin sealant compared with standard care in non-emergency surgery in adults. The primary outcome was risk of developing seroma and haematoma. Only RCTs were used to inform clinical effectiveness and both RCTs and observational studies were used for the assessment of harms related to the use of fibrin sealant. Two reviewers independently screened all titles and abstracts to identify potentially relevant studies. Data extraction was undertaken by one reviewer and validated by a second. The quality of included studies was assessed independently by two reviewers using the Cochrane Collaboration risk-of-bias tool for RCTs and the Centre for Reviews and Dissemination guidance for adverse events for observational studies. A fixed-effects model was used for meta-analysis. RESULTS We included 186 RCTs and eight observational studies across 14 surgical specialties and five reports from the regulatory bodies. Most RCTs were judged to be at an

  4. Application of fibrin sealant at the urethrovesical anastomosis in robotic assisted radical prostatectomy: does it enable earlier Foley catheter and Jackson-Pratt drain removal?

    PubMed

    Flury, Sarah C; Starnes, Danielle N; Steers, William D

    2008-01-01

    Leakage at the urethrovesical anastomosis in the post-operative period can result in morbidity including ileus. We examined the effectiveness of using a fibrin sealant at the anastomosis to limit urine leakage thereby facilitating earlier Jackson-Pratt drain and Foley catheter removal following robotic assisted laparoscopic prostatectomy (RALRP). Forty consecutive patients underwent RALRP by one surgeon at our institution. The first 20 patients underwent standard operation and served as the control group. The subsequent 20 patients underwent the same operation with addition of fibrin sealant following a running absorbable sutured urethrovesical anastomosis. The two groups were compared for age (60.5 vs. 58.2 years), pre-operative PSA (5.23 vs. 4.71), Gleason score (6.3 vs. 6.5), stage at resection, and prostate size at resection (51.7 vs. 47.7 g). Wilcoxon rank sum test determined no statistically significant differences in the groups. Patients in the fibrin sealant group had 1.3 versus 2.1 days with a Jackson-Pratt drain, 9.75 versus 12.1 days with a catheter, and an average of 38.6 versus 63.2 cc of drainage per shift. Catheters were removed when a cystogram demonstrated no extravasation of contrast. Two patients in the control group and no patients in the fibrin sealant group had large-volume leakage and ileus post-operatively. In patients undergoing RALRP, application of fibrin sealant at the urethrovesical anastomosis appears to facilitate sealing, thereby allowing earlier removal of the JP drain, by 0.8 days, and the Foley catheter, by 2.35 days, than in controls. No patients in the fibrin sealant group suffered post-operative ileus. This adjunct may be especially useful early in the learning process to reduce morbidity.

  5. Autologous platelet gel and fibrin sealant enhance the efficacy of total knee arthroplasty: improved range of motion, decreased length of stay and a reduced incidence of arthrofibrosis.

    PubMed

    Everts, Peter A M; Devilee, Roger J J; Oosterbos, Cornelis J M; Mahoney, Christine Brown; Schattenkerk, Maarten Eeftinck; Knape, Johannes T A; van Zundert, André

    2007-07-01

    In this study we describe the potential role of autologous platelet gel and fibrin sealant in unilateral total knee arthroplasty to improve the postoperative range of motion and to reduce the incidence of arthrofibrosis. Total knee arthroplasty is often associated with a considerable amount of post-operative blood loss. Persistent limited motion directly after surgery may ultimately result in arthrofibrosis. To counteract these effects we investigated whether the use of autologous derived platelet gel and fibrin sealant would reduce postoperative blood loss, decrease the impaired range of motion and the incidence of arthrofibrosis. All patients were consecutively operated and assigned to the study or control groups. Study group patients (n = 85) were treated with the application of autologous platelet gel and fibrin sealant at the end of surgery. Eighty patients were operated without the use of platelet gel and fibrin sealant, and served as the control group. The postoperative hemoglobin decrease, range of motion and length of hospitalization were recorded. During a 5-month postoperative period patients were followed to observe the incidence of arthrofibrosis. In patients in the treatment group the hemoglobin concentration in blood decreased significantly less when compared to the control group. They also showed a superior postoperative range of motion when compared to those of the control group (P < 0.001). The incidence of arthrofibrosis and subsequent forced manipulation was significantly less (P < 0.001) in patients managed with platelet gel and fibrin sealant. We conclude that peri-operatively applied platelet gel and fibrin sealant may improve the range of motion after total knee arthroplasty, decreases the length of stay and may reduce the incidence of arthrofibrosis.

  6. Influence of fibrin sealant in preventing postoperative seroma and normalizing the abdominal wall after laparoscopic repair of ventral hernia.

    PubMed

    Morales-Conde, Salvador; Suárez-Artacho, Gonzalo; Socas, María; Barranco, Antonio

    2013-09-01

    Seroma after laparoscopic ventral hernia repair (LVHR) has been related to certain complications of the technique, such as recurrences and postoperative pain. The aim of this study was to assess whether percutaneous application of fibrin sealant in the hernia sac after LVHR reduces the incidence and volume of the postoperative seroma, and to analyze whether the percentage of patients achieving complete normalization of the abdominal wall increases. Prospective and comparative study. Patients were distributed into 2 control-case groups. Group 1 comprised patients submitted to LVHR using the double crown technique and a compressing bandage as the only method for prevent seroma. Group 2 comprised patients admitted to LVHR using the same technique together with percutaneous injection of fibrin sealant in the sac, and later applying the same bandage. Patients were examined clinically and radiologically at 7 days, 1 month, and 3 months after surgery. Twenty-five patients were included in each group. There were significant differences in the incidence of seroma by the day 7 after surgery (92% in group 1 vs. 64 % in group 2, p = 0.017) and by 1 month (72% in group 1 vs. 28% in group 2, p = 0.002). The difference was also significant regarding the achievement of normalization of the abdominal wall by day 7 (24% in group 1 vs. 52% in group 2, p = 0.041) and by month 1 (64% in group 1 vs. 88% in group 2, p = 0.047) after operation. Volume of seroma was larger among patients of group 1 after the week (p = 0.002) and 1 month after operation (p = 0.001). Fibrin sealant application after LVHR reduces the incidence and volume of the seroma 7 days and 1 month after surgery. The treated patients obtain a larger normalization of the abdominal wall 1 week and 1 month after the operation.

  7. Influence of calcium chloride and aprotinin in the in vivo biological performance of a composite combining biphasic calcium phosphate granules and fibrin sealant.

    PubMed

    Le Guehennec, Laurent; Goyenvalle, Eric; Aguado, Eric; Pilet, Paul; Spaethe, Reiner; Daculsi, Guy

    2007-08-01

    Highly bioactive biomaterials have been developed to replace bone grafts in orthopedic revision and maxillofacial surgery for bone augmentation. A mouldable, self-hardening material can be obtained by combining TricOs Biphasic Calcium Phosphate Granules and Tissucol Fibrin Sealant. Two components, calcium chloride and antifibrinolytic agents (aprotinin), are essential for the stability of the fibrin clot. The ingrowth of cells in composites combining sealants without calcium chloride or with a low concentration of aprotinin was evaluated in vivo in an experiment on rabbits. Bone colonization was compared using TricOs alone or with the composite made from TricOs and the standard fibrin sealant. Without the addition of calcium chloride, the calcium ions released by the ceramic component interacted with the components of the sealant too late to stabilize the clot. With a low concentration of aprotinin, the degradation of the clot occurred more quickly, leading to the absence of a scaffold on which the bone cells could colonize the composite. Our results indicate that a stable fibrin scaffold is crucial for bone colonization. The low calcium chloride and low aprotinin groups have shown lower bone growth. Further studies will be necessary to determine the minimal amount of antifibrinolytic agent (aprotinin) necessary to allow the same level of osteogenic activity as the TricOs-fibrin glue composite.

  8. Effects of low-level laser therapy on autogenous bone graft stabilized with a new heterologous fibrin sealant.

    PubMed

    de Oliveira Gonçalves, Jéssica Barbosa; Buchaim, Daniela Vieira; de Souza Bueno, Cleuber Rodrigo; Pomini, Karina Torres; Barraviera, Benedito; Júnior, Rui Seabra Ferreira; Andreo, Jesus Carlos; de Castro Rodrigues, Antonio; Cestari, Tania Mary; Buchaim, Rogério Leone

    2016-09-01

    Autogenous bone grafts are used to repair bone defects, and the stabilization is needed for bone regeneration. Laser photobiomodulation is a modality of treatment in clinical practice for tissue regeneration, and it has therapeutic effects as an anti-inflammatory, analgesic and modulating cellular activity. The aim of the present study was to evaluate the effects of low-level laser therapy (LLLT) on an autogenous bone graft integration process stabilized with a new heterologous fibrin sealant. Forty rats were divided into two groups: Autogenous Fibrin Graft (AFG, n=20), in which a 5mm dome osteotomy was conducted in the right parietal bone and the graft was adhered to the left side using fibrin sealant; and Autogenous Fibrin Graft Laser (AFGL, n=20), which was subjected to the same procedures as AFG with the addition of LLLT. The treatment was performed immediately following surgery and then three times a week until euthanasia, using an 830nm laser (30mW, 6J/cm(2), 0.116cm(2), 258.6mW/cm(2), 2.9J). Five animals from each group were euthanized at 10, 20, 30 and 40days postoperative, and the samples were submitted to histomorphological and histomorphometric analysis. Partial bone regeneration occurred, with new bone tissue integrating the graft to the recipient bed and small areas of connective tissue. Comparative analysis of the groups at the same intervals revealed minor interfaces in group AFGL, with statistically significant differences (p<0.05) at all of the analyzed intervals (10days p=0.0087, 20days p=0.0012, 30days p<0.0001, 40days p=0.0142). In conclusion, low-level laser therapy stimulated bone regeneration and accelerated the process of integration of autogenous bone grafts.

  9. Treatment of 213 patients with Symptomatic Tarlov Cysts by CT-guided Percutaneous Injection of Fibrin Sealant

    PubMed Central

    Murphy, Kieran; Oaklander, Anne Louise; Elias, Gavin; Kathuria, Sudhir; Long, Donlin M.

    2015-01-01

    Purpose The purpose of this study was to analyze the safety and efficacy of intervention in patients with symptomatic Tarlov cysts by percutaneous, CT-guided two-needle cyst aspiration and fibrin sealant injection. Materials and Methods This study was designed to assess outcomes in patients who underwent CT-guided aspiration and injection of one or more sacral Tarlov cysts at Johns Hopkins Hospital between the years of 2003 and 2013. In all, 289 cysts were treated in 213 consecutive patients. All of these patients were followed for at least six months; 90% were followed for one year and 83% were followed for three to six years. The aspiration-injection procedure employed two needles and was carried out with local anesthesia and intravenous analgesia. In the fibrin injection stage of the procedure, a commercially available fibrin sealant was injected into the cyst through the deep needle (Tisseel VH; Baxter Healthcare, Westlake Village, California). Results One year post-procedure, excellent results had been obtained in 104 patients (54.2% of patients followed) and good or satisfactory results had been obtained in 53 patients (27.6%). Thus, 157 patients (81.8%) in all were initially satisfied with the outcome of treatment. At three to six years post-procedure, 74.0% of patients followed were satisfied with treatment. There were no significant complications. Conclusions The aspiration-injection technique described herein constitutes a safe and efficacious treatment option that holds promise for relieving cyst-related symptoms in many patients with very small risk. PMID:26405086

  10. Fibrin sealant for closure of mucosal penetration at the cardia during peroral endoscopic myotomy: A retrospective study at a single center

    PubMed Central

    Zhang, Wen-Gang; Linghu, En-Qiang; Li, Hui-Kai

    2017-01-01

    AIM To assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia during peroral endoscopic myotomy (POEM). METHODS Twenty-four patients who underwent POEM and experienced mucosal injury of the cardia during the procedure were retrospectively identified. Of the 24 patients, 21 had mucosal penetration and 3 had only slight mucosal damage without penetration. The 21 patients with mucosal penetration received fibrin sealant for closure at the site of penetration. Penetration-related characteristics, treatment, and recovery were reviewed for all 21 patients to assess the efficacy and safety of fibrin sealant for closure of mucosal penetration at the cardia. Clinical data, including general characteristics, procedure-related parameters, Eckardt scores, lower esophageal sphincter pressures (LESP), and esophagogastroduodenoscopy (EGD) results, were analyzed to determine their influence on treatment success after mucosal penetration during POEM. RESULTS All 21 patients had a solitary mucosal penetration in the cardia (12 in esophageal region of the cardia, 9 in the stomach region of the cardia, and 1 in both the esophageal and stomach regions). Twelve had a hole-like penetration and 9 had a linear penetration. For those with a hole-like penetration, the mean size was 0.14 cm2 (0.02-0.32 cm2). For those with a linear penetration, the median size was 0.37 cm (0.10-1.00 cm). Closure of the mucosal penetration using fibrin sealant was performed successfully in all 21 patients (two patients required 5 mL fibrin sealant, and the remaining 19 patients required 2.5 mL). Two patients had a nasogastric tube placed for five days after POEM; the remaining 19 patients were kept fasting for 3 d. All 21 patients were discharged after a median of 5 d (range: 5-7 d) postoperatively. During a median 42 mo (range: 9-62 mo) follow-up, all 21 patients with a mucosal penetration successfully healed without the occurrence of infection, ulcer, or esophagitis

  11. Early experience of the use of fibrin sealant in the management of children with pilonidal sinus disease.

    PubMed

    Smith, Caroline Mary; Jones, Abigail; Dass, Dipankar; Murthi, Govind; Lindley, Richard

    2015-02-01

    The use of fibrin sealant in the management of pilonidal sinus disease has not previously been described in children. We present our experience of primary pit excision and use of fibrin sealant (PEF) and compare outcomes with lateralising flap procedures (LFP). A single centre retrospective case note review of all children who had undergone a definitive procedure for pilonidal sinus from August 2006 to Dec 2013 was performed using data expressed as median (range) and compared using Fisher's exact test. P<0.05 was regarded as significant. Forty-one children were identified having undergone 49 procedures, with median age 15 (12-16 years) and follow up 32 (8-92) months. Groups were comparable for disease severity. Ten children underwent primary PEF and twenty-six LFP. Two children had recurrence following primary PEF and had repeat PEF which was curative. Overall recurrence rates following PEF procedure were comparable to LFP (17% vs 21%; P=1.0). There were no wound dehiscences in the PEF group and one wound infection. There was one wound dehiscence and one wound infection in the LFP group. Median operative time for PEF was lower than LFP (20 vs 60 min, P=0.001). 83% of PEF procedures were performed as day cases. One child was lost to follow up, and two children progressed to adult services. We recommend PEF in children with pilonidal sinus disease as primary treatment and for recurrence. PEF has comparable recurrence and wound infection rates to LFPs, is performed as day case, has shorter anaesthetic times, and the risk of wound dehiscence is avoided. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Fibrin sealant combined with fibroblasts and platelet-derived growth factor enhance wound healing in excisional wounds.

    PubMed

    Mogford, Jon E; Tawil, Bill; Jia, Shengxian; Mustoe, Thomas A

    2009-01-01

    We test the hypothesis that the fibrinogen-thrombin formulation of fibrin sealant combined with fibroblasts and PDGF-BB enhance cutaneous wound healing. Four formulations varying in fibrinogen and thrombin concentration were applied to full-thickness biopsy wounds in the rabbit ear cutaneous wound healing model with or without cultured rabbit dermal fibroblasts (RDFs; 3 x 10(5) cells/wound) embedded in the fibrinogen component. At post-wounding day 7, there was no difference in the diluted vs. non-diluted formulations for either the promotion of granulation tissue coverage of the open wounds or total granulation tissue area when tested without embedded cells. Including the RDFs, the highest degree of wound coverage by granulation tissue was observed in the combined dilution formulation (17.3 mg/mL fibrinogen, 167 U/mL thrombin; n=10 wounds) that was 167% (p<0.05) of the nondiluted FS containing cells (50 mg/mL fibrinogen, 250 U/mL thrombin; n=10 wounds). Inclusion of fibroblasts increased granulation tissue area within the wounds vs. FS alone (p<0.05) for each diluted formulation although no differences in this parameter were observed within each group (FS alone or with embedded cells). However, addition of the vulnerary growth factor PDGF-BB (3 mg; n=4) with the embedded RDFs in the combined dilution formulation increased granulation tissue area over two-fold (p<0.01) over FS alone. Additionally, the presence of the RDFs promoted incorporation of the granulation tissue with and epithelial migration over the FS suggesting an active interaction between cells delivered to the wound by FS and the host repair cells. The findings suggest the progress of cutaneous defect repair can be enhanced by ex vivo cell delivery in fibrin sealant.

  13. Treatment of 213 Patients with Symptomatic Tarlov Cysts by CT-Guided Percutaneous Injection of Fibrin Sealant.

    PubMed

    Murphy, K; Oaklander, A L; Elias, G; Kathuria, S; Long, D M

    2016-02-01

    There has been a steady progression of case reports and a small surgical series that report successful surgical treatment of Tarlov cysts with concomitant relief of patients' symptoms and improvement in their neurological dysfunction, yet patients are still told that these lesions are asymptomatic by physicians. The purpose of this study was to analyze the efficacy and safety of intervention in 213 consecutive patients with symptomatic Tarlov cysts treated by CT-guided 2-needle cyst aspiration and fibrin sealing. This study was designed to assess outcomes in patients who underwent CT-guided aspiration and injection of ≥1 sacral Tarlov cyst at Johns Hopkins Hospital between 2003 and 2013. In all, 289 cysts were treated in 213 consecutive patients. All these patients were followed for at least 6 months, 90% were followed for 1 year, and 83% were followed for 3-6 years. The aspiration-injection procedure used 2 needles and was performed with the patients under local anesthesia and intravenous anesthesia. In the fibrin-injection stage of the procedure, a commercially available fibrin sealant was injected into the cyst through the deep needle (Tisseel VH). One year postprocedure, excellent results were obtained in 104 patients (54.2% of patients followed), and good or satisfactory results were obtained in 53 patients (27.6%). Thus, 157 patients (81.8%) in all were initially satisfied with the outcome of treatment. At 3-6 years postprocedure, 74.0% of patients followed were satisfied with treatment. There were no clinically significant complications. The aspiration-injection technique described herein constitutes a safe and efficacious treatment option that holds promise for relieving cyst-related symptoms in many patients with very little risk. © 2016 by American Journal of Neuroradiology.

  14. A comparison of bone generation capability in rabbits using tooth ash and plaster of Paris with platelet-rich plasma or fibrin sealant.

    PubMed

    Kim, Bong-Kyun; Kim, Su-Gwan; Kim, Seo-Yoon; Lim, Sung-Chul; Kim, Young-Kyun

    2010-09-01

    Increased attention has been focused on determining the most efficacious materials for generalized bone grafts. This article presents the results of a histomorphometric analysis of bone healing in the calvaria of rabbits. The study compared the use of a tooth ash and plaster of Paris mixture alone, in association with platelet-rich plasma (PRP), and in association with fibrin sealant. Twelve rabbits were divided into control (group 1) and experimental groups (groups 2, 3, and 4). Group 1 was maintained as an unfilled control, and tooth ash and plaster of Paris were used in group 2, tooth ash and plaster of Paris with PRP were used in group 3, and tooth ash and plaster of Paris with fibrin sealant (Tissucol Duo Quick) were used in group 4. One-half of the animals were killed after 4 weeks, and the rest were killed after 8 weeks. Bone samples were taken from the defect areas, and newly formed bone was analyzed histomorphometrically. The rate of new bone formation in groups 2, 3, and 4 was significantly higher than the rate in the control group. The rate of new bone formation in groups 3 and 4 was higher than the rate in group 2, but the difference was not statistically significant. The concomitant use of PRP or fibrin sealant with tooth ash and plaster of Paris graft materials may have a positive effect on bone healing. Copyright (c) 2010 Mosby, Inc. All rights reserved.

  15. Fetal membrane patch and biomimetic adhesive coacervates as a sealant for fetoscopic defects.

    PubMed

    Mann, Lovepreet K; Papanna, Ramesha; Moise, Kenneth J; Byrd, Robert H; Popek, Edwina J; Kaur, Sarbjit; Tseng, Scheffer C G; Stewart, Russell J

    2012-07-01

    Iatrogenic preterm premature rupture of membranes after fetoscopic procedures affects 10-47% of patients, secondary to the non-healing nature of membranes and the separation of layers during the entry. In this study we developed an in vitro model to mimic the uterine wall-fetal membrane interface using a water column with one end sealed with human fetal membranes and poultry breast, and a defect was created with an 11 French trocar. Further, a fetal membrane patch in conjunction with multiphase adhesive coacervates modeled after the sandcastle worm bioadhesive was tested for sealing of an iatrogenic defect. The sealant withstood an additional traction of 12 g for 30-60 min and turbulence of the water column without leakage of fluid or slippage. The adhesive is non-toxic when in direct contact with human fetal membranes in an organ culture setting. A fetal membrane patch with multiphase adhesive complex coacervates may help to seal the defect and prevent iatrogenic preterm premature rupture of the membranes. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Surgical Treatment of Pressure Ulcers with a Fibrin Sealant in Patients with Spinal Cord Injury: A Cost-Consequence Analysis.

    PubMed

    Velasco, Jose Manuel Arévalo; Lozano, Virginia; Oyagüez, Itziar; Casado, Miguel Angel

    2015-11-01

    A comparative study was performed to evaluate the effectiveness and costs of a fibrin sealant (Tissucol Duo [known as Tisseel in the United States], Baxter International, Deerfield, Illinois) to improve postoperative outcomes in patients with spinal cord injury undergoing surgical treatment for pressure ulcers (PrUs). Between January and June 2011, 27 patients underwent surgical treatment for PrUs with the direct application of Tissucol Duo sprayed before closure. The costs and outcomes obtained in this cohort were compared with those obtained in a previous retrospective study where 71 patients underwent conventional surgery. Lower rates of hematoma-seroma were observed in the study group (3.7% vs 33.8%; P < .05). Drain removal occurred earlier (10 vs 15 days; P < .05), and the average drain volume was also lower (155 vs 360 mL; P < .05) for this group. The mean length of hospital stay was significantly lower in the study group and was the main contributing factor to the overall costs. The application of Tissucol Duo during surgical treatment of PrUs in patients with spinal cord injury has been shown to be effective in reducing postoperative complications and in shortening the duration of the hospital stay with a consequent savings in costs.

  17. Argon beam coagulation versus fibrin sealant for hemostasis following liver resection: a randomized study in a porcine model.

    PubMed

    Katkhouda, Namir; Friedlander, Melanie; Darehzereshki, Ali; Mason, Rodney J; Zehetner, Joerg; Moazzez, Ashkan; Chan, Linda S; Kiyabu, Milton; Kirkman, Erlinda; Kirkman, Paul; Ravari, Farrokh; Degnera, Evgeniya; Drangsholt, Siri; Khalaf, Naila

    2013-01-01

    Bleeding from the raw liver surface represents a significant surgical complication after elective liver resection or hepatic trauma. The application of argon beam coagulation (ABC) has been proposed to improve hemostasis, but is associated with significant necrosis of the liver parenchyma. Topical hemostatic agents, i.e. fibrin sealant (FS), have also been recommended, yet the optimal management is under debate. This study compares the efficacy and safety of both methods following liver resection in an animal model. Twenty pigs underwent liver resection, and were then randomized into ABC or FS group for treatment of raw liver surfaces. Intraoperative and postoperative parameters were studied. Animals were sacrificed at day 12, and extent of necrosis was assessed using a scoring system and morphometry. Intraoperative parameters did not show any significant difference between two groups except for shorter time of application in the FS group. Postoperatively, animals in the FS group showed significantly higher hemoglobin levels (p=0.0001). Histologically, FS showed a smaller depth of necrosis than ABC (p=0.022). The use of FS is superior to ABC for management of the raw liver surface after liver resection, in terms of application time, postoperative bleeding and the extent of liver tissue necrosis.

  18. Fibrin patch-based insulin-like growth factor-1 gene-modified stem cell transplantation repairs ischemic myocardium

    PubMed Central

    Li, Jun; Zhu, Kai; Yang, Shan; Wang, Yulin; Guo, Changfa; Yin, Kanhua; Wang, Chunsheng

    2015-01-01

    Bone marrow mesenchymal stem cells (BMSCs), tissue-engineered cardiac patch, and therapeutic gene have all been proposed as promising therapy strategies for cardiac repair after myocardial infarction. In our study, BMSCs were modified with insulin-like growth factor-1 (IGF-1) gene, loaded into a fibrin patch, and then transplanted into a porcine model of ischemia/reperfusion (I/R) myocardium injury. The results demonstrated that IGF-1 gene overexpression could promote proliferation of endothelial cells and cardiomyocyte-like differentiation of BMSCs in vitro. Four weeks after transplantation of fibrin patch loaded with gene-modified BMSCs, IGF-1 overexpression could successfully promote angiogenesis, inhibit remodeling, increase grafted cell survival and reduce apoptosis. In conclusion, the integrated strategy, which combined fibrin patch with IGF-1 gene modified BMSCs, could promote the histological cardiac repair for a clinically relevant porcine model of I/R myocardium injury. PMID:25767192

  19. Injectable calcium phosphate cement and fibrin sealant recombined human bone morphogenetic protein-2 composite in vertebroplasty: an animal study

    PubMed Central

    Qian, Guang; Dong, Youhai; Yang, Wencheng; Wang, Minghai

    2012-01-01

    Polymethylmethacrylate (PMMA) is currently the most commonly-used material, but it may induce adjacent vertebral fracture due to low degradation and high strength. Our study evaluated the feasibility of injectable calcium phosphate cement (ICPC) and fibrin sealant (FS) as an injectable compound carrier of human bone morphogenetic protein-2 (rhBMP-2) in New Zealand rabbits for vertebroplasty. Results showed ICPC/FS/rhBMP-2 composites induced alkaline phosphatase most effectively at 2 and 4 weeks after implantation. Histological examination confirmed that new bone and vessels developed at 4 weeks in the ICPC/FS/rhBMP-2 group. At 8 weeks, parts of the ICPC/FS/rhBMP-2 cement degraded with mature bone tissues and neovascularization. New bone was observed by MicroCT to form early and massively, and the ossification was almost synchronous with the material degradation. In the PMMA Group, however, no new bone formation or material degradation was found. The stiffness and tension of vertebral bodies implanted with ICPC/FS/rhBMP-2 were weaker than those of normal vertebral bodies as well as vertebral bodies implanted with PMMA at 4 weeks (p<0.05). At 8 weeks, the stiffness and tension of vertebral bodies implanted with ICPC/FS/rhBMP-2 became strong; no significant difference was noted in the stiffness and tension, compared with normal vertebral bodies (p>0.05), while they were significantly lower, compared with vertebral bodies implanted with PMMA (p<0.05). It is concluded that, with good characteristics of osteoinductivity, the bone substitution is synchronous with material degradation. PMID:23198937

  20. Hemostasis and other benefits of fibrin sealants/glues in spine surgery beyond cerebrospinal fluid leak repairs

    PubMed Central

    Epstein, Nancy E.

    2014-01-01

    Background: Fibrin sealants (FS)/glues (FG) are primarily utilized in spinal surgery to either strengthen repairs of elective (e.g., intradural tumors/pathology) or traumatic cerebrospinal fluid (CSF) fistulas. Here, additional roles/benefits of FS/FG in spine surgery are explored; these include increased hemostasis, reduction of scar, reduction of the risk of infection if impregnated with antibiotics, and its application to restrict diffusion and limit some of the major complications attributed to the controversial “off-label” use of bone morphogeneitc protein (rhBMP-2/INFUSE). Methods: We reviewed multiple studies, focusing not just on the utility of FS/FG in the treatment of CSF fistulas, but on its other applications. Results: FS/FG have been primarily used to supplement elective/traumatic dural closure in spinal surgery. However, FS/FG also contribute to; hemostasis, reducing intraoperative/postoperative bleeding/transfusion requirements, length of stay (LOS)/costs, reduced postoperative scar/radiculitis, and infection when impregnated with antibiotics. Nevertheless, one should seriously question whether FS/FG should be applied to prevent diffusion and limit major complications attributed to the “off-label” use of BMP/INFUSE (e.g., limit/prevent heterotopic ossification, dysphagia/respiratory decompensation, and new neurological deficits). Conclusions: FS/FG successfully supplement watertight dural closure following elective (e.g., intradural tumor) or traumatic CSF fistulas occurring during spinal surgery. Additional benefits include: intraoperative hemostasis with reduced postoperative drainage, reduced transfusion requirements, reduced LOS, cost, scar, and prophylaxis against infection (e.g., impregnated with antibiotics). However, one should seriously question whether FS/FG should be used to contain the diffusion of BMP/INFUSE and limit its complications when utilized “off-label”. PMID:25289150

  1. Fibrin Sealants and Quilting Suture for Prevention of Seroma Formation Following Latissimus Dorsi Muscle Harvest: A Systematic Review and Meta-analysis.

    PubMed

    Lee, Kyeong-Tae; Mun, Goo-Hyun

    2015-06-01

    Despite popular use of fibrin sealants and quilting sutures for prevention of seroma formation at the donor site of the latissimus dorsi (LD) muscle flap, there is still no consensus regarding their efficacy. The present review estimates the potential benefits of fibrin and quilting suture for reducing seroma-related morbidity following LD muscle harvest. Using Medline, Ovid, and Cochrane databases, two-arm studies evaluating the efficacy of fibrin sealants, quilting suture, or their combination for prevention of seroma formation following LD muscle transfer were searched. The outcome measure was the incidence of seroma, total drainage volume from the back, periods of drainage in situ, volume of seroma, and frequency of aspiration for treatment of seroma. The efficacy on reducing the seroma-related morbidity for each procedure was estimated by meta-analytic methodology. Fourteen studies were analyzed. Fibrin alone failed to reduce seroma-related morbidities compared with no intervention, while fibrin instillation combined with quilting suture halved the risk of seroma formation (relative risk (RR): 0.51, 95 % CI 0.12-2.16) and significantly reduced total drainage volume (mean difference (MD); -320.80, 95 % CI -389.92 to -251.68) and drain indwelling periods (MD -1.62, 95 % CI -2.91 to -0.33) compared with quilting suture alone. Quilting suture had significant protective effects on reducing the risk of seroma formation (RR 0.38, 95 % CI 0.19-0.75), total drainage volume (MD -284.10, 95 % CI -474.61 to -93.60), and drain indwelling periods (MD -3.65, 95 % CI -5.43 to -1.87), and its efficacy was enhanced by combining with fibrin. According to this review, both fibrin and quilting sutures contributed in varying degrees to reducing seroma-related morbidity following LD muscle transfer, and their combination can have a synergistic effect. Although large-scaled, randomized studies are needed, the combination of both procedures may be considered an effective option for

  2. A unique heterologous fibrin sealant (HFS) as a candidate biological scaffold for mesenchymal stem cells in osteoporotic rats.

    PubMed

    Orsi, Patrícia Rodrigues; Landim-Alvarenga, Fernanda Cruz; Justulin, Luis Antônio; Kaneno, Ramon; de Assis Golim, Marjorie; Dos Santos, Daniela Carvalho; Creste, Camila Fernanda Zorzella; Oba, Eunice; Maia, Leandro; Barraviera, Benedito; Ferreira, Rui Seabra

    2017-09-29

    The injection of mesenchymal stem cells (MSCs) directly into the bone of osteoporotic (OP) patients for rapid recovery has been studied worldwide. Scaffolds associated with MSCs are used to maintain and avoid cell loss after application. A unique heterologous fibrin sealant (HFS) derived from snake venom was evaluated for the cytotoxicity of its main components and as a three-dimensional biological scaffold for MSCs to repair a critical femur defect in osteoporotic rats. The cytotoxicity of HFS was assessed using a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) assay and transmission electron microscopy. The cells were cultured, characterized by flow cytometry and differentiated into the osteogenic lineage. Two-month-old rats underwent ovariectomy to induce OP. After 3 months, a 5 mm critical bone defect was made in the distal end of the rat femurs and filled with HFS; HFS + MSCs; and HFS + MSCs D (differentiated into the osteogenic lineage) to evaluate the effects. An injury control group (injury and no treatment) and blank control group (no injury and no treatment) were also included. The animals were observed at days 14 and 28 by microtomographic (micro-CT) analyses, histologic and biochemical analysis, as well as scanning electron microscopy. The results revealed that one of the compounds of HFS, the thrombin-like enzyme extracted from snake venom, had no cytotoxic effects on the MSCs. OP was successfully induced, as demonstrated by the significant differences in the levels of 17β-estradiol, Micro-CT analyses and alkaline phosphatase between the ovariectomized (OVX) and non-ovariectomized (NOVX) groups. The histological data revealed that at 14 days after surgery in both the OVX and NOVX animals, the HFS + CTMs and HFS + CTMsD showed a higher formation of bone cells at the site in relation to the control group (without treatment). Collagen formation was evidenced through bone neoformation in all treated and control groups

  3. Prophylactic use of fibrin sealant (ARTISS(™) ) for facilitating safe transition to drain-free thyroid surgery: a single-centre case series review of 109 procedures.

    PubMed

    Heyes, Richard; Ramdoo, Krishan; Manjaly, Joseph G; Charn, Tze Choong; Tatla, Taran

    2017-02-24

    Despite a lack of evidence to support drain insertion in thyroid surgery, drain placement, to prevent rapidly expanding haematoma which occurs in around 1% of cases, remains common (1,2,3) . Throughout surgery there has been a drive towards reducing postoperative length of hospital admission. For day-case thyroidectomy to become a widely adopted clinical reality, the use of drains requires abandonment, but beyond this, the cause for surgeons' reticence to practise drain-free surgery, namely haematoma risk, needs to be addressed. This paper describes a study conducted to examine the efficacy of ARTISS(™) , a commercially available thrombin-dilute fibrin sealant, in thyroid surgery to permit safe transition to drain-free surgery. This article is protected by copyright. All rights reserved.

  4. Tolerance and osteointegration of TricOs(TM)/MBCP(®) in association with fibrin sealant in mastoid obliteration after canal wall-down technique for cholesteatoma.

    PubMed

    Franco-Vidal, Valérie; Daculsi, Guy; Bagot d'Arc, Maurice; Sterkers, Olivier; Smail, Mustapha; Robier, Alain; Bordure, Philippe; Claros, Pedro; Paiva, Antonio; Darrouzet, Vincent; Anthoine, Emmanuelle; Bebear, Jean-Pierre

    2014-04-01

    The TricOs™/MBCP(®) and fibrin sealant composite was a convenient, effective, and well-tolerated material for mastoid cavity filling and immediate reconstruction of the external auditory meatus after cholesteatoma surgery with canal wall down (CWD). To assess the tolerance and osteointegration of a bone graft substitute, TricOs™/MBCP(®), in association with fibrin sealant for filling the mastoid cavity after cholesteatoma surgery using the CWD technique. In this prospective observational study 57 patients with cholesteatoma suitable for CWD were recruited from April 2006 to April 2008 and followed up for 1 year. The mastoid cavity was filled with TricOs™/MBCP(®) followed by immediate reconstruction of the external auditory meatus covered with fascia temporalis and/or cartilage. The main outcome was skin tolerance assessed by a novel weighted score emphasizing long-term results. The typical weighted reference score was 1.67; skin tolerance was considered acceptable if 75% of patients had a score ≤ 1.67. Secondary outcomes were otorrhea and/or otalgia, hearing, and osteointegration assessed through computed tomography scanning at 12 months. Forty-one patients had a complete follow-up; 34 (82.3%) patients achieved the main end point with scores ≤ 1.67. Otorrhea decreased postoperatively. No otalgia interfering with daily tasks was reported. Ossicular reconstruction was carried out in 29 patients. Absence of cochlear toxicity was confirmed by unimpaired bone conduction. Preoperative and postoperative speech audiometry results were similar. No serious adverse events were observed. Osteointegration was satisfactory with hyperdensity or intermediate density in 95% of patients at 12 months.

  5. The effect of TISSEEL fibrin sealant on seroma formation following complex abdominal wall hernia repair: a single institutional review and derived cost analysis.

    PubMed

    Azoury, S C; Rodriguez-Unda, N; Soares, K C; Hicks, C W; Baltodano, P A; Poruk, K E; Hu, Q L; Cooney, C M; Cornell, P; Burce, K; Eckhauser, F E

    2015-12-01

    The authors evaluated the ability of a fibrin sealant (TISSEEL™: Baxter Healthcare Corp, Deerfield, IL, USA) to reduce the incidence of post-operative seroma following abdominal wall hernia repair. We performed a 4-year retrospective review of patients undergoing abdominal wall hernia repair, with and without TISSEEL, by a single surgeon (FEE) at The Johns Hopkins Hospital. Demographics, surgical risk factors, operative data and 30-day outcomes, including wound complications and related interventions, were compared. The quantity and cost of Tisseel per case was reviewed. A total of 250 patients were evaluated: 127 in the TISSEEL group and 123 in the non-TISSEEL control group. The average age for both groups was 56.6 years (P = 0.97). The majority of patients were female (TISSEEL 52.8%, non-TISSEEL 56.1%, P = 0.59) and ASA Class III (TISSEEL 56.7%, non-TISSEEL 58.5%, P = 0.40). There was no difference in the average defect size for both groups (TISSEEL 217 ± 187.6 cm(2), non-TISSEEL 161.3 ± 141.5 cm(2), P = 0.36). Surgical site occurrences occurred in 18.1% of the TISSEEL and 13% of the non-TISSEEL group (P = 0.27). There was a trend towards an increased incidence of seroma in the TISSEEL group (TISSEEL 11%, non-TISSEEL 4.9%, P = 0.07). A total of $124,472.50 was spent on TISSEEL, at an average cost of $995.78 per case. In the largest study to date, TISSEEL™ application offered no advantage for the reduction of post-operative seroma formation following complex abdominal hernia repair. Moreover, the use of this sealant was associated with significant costs.

  6. Postinfarction Functional Recovery Driven by a Three-Dimensional Engineered Fibrin Patch Composed of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells

    PubMed Central

    Roura, Santiago; Soler-Botija, Carolina; Bagó, Juli R.; Llucià-Valldeperas, Aida; Férnandez, Marco A.; Gálvez-Montón, Carolina; Prat-Vidal, Cristina; Perea-Gil, Isaac; Blanco, Jerónimo

    2015-01-01

    Considerable research has been dedicated to restoring myocardial cell slippage and limiting ventricular remodeling after myocardial infarction (MI). We examined the ability of a three-dimensional (3D) engineered fibrin patch filled with human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) to induce recovery of cardiac function after MI. The UCBMSCs were modified to coexpress luciferase and fluorescent protein reporters, mixed with fibrin, and applied as an adhesive, viable construct (fibrin-cell patch) over the infarcted myocardium in mice (MI-UCBMSC group). The patch adhered well to the heart. Noninvasive bioluminescence imaging demonstrated early proliferation and differentiation of UCBMSCs within the construct in the postinfarct mice in the MI-UCBMSC group. The implanted cells also participated in the formation of new, functional microvasculature that connected the fibrin-cell patch to both the subjacent myocardial tissue and the host circulatory system. As revealed by echocardiography, the left ventricular ejection fraction and fractional shortening at sacrifice were improved in MI-UCBMSC mice and were markedly reduced in mice treated with fibrin alone and untreated postinfarction controls. In conclusion, a 3D engineered fibrin patch composed of UCBMSCs attenuated infarct-derived cardiac dysfunction when transplanted locally over a myocardial wound. Significance Ischemic heart failure (HF) is the end stage of many cardiovascular diseases, including myocardial infarction. The only definitive treatment for HF is cardiac transplant, which is hampered by limited number of heart donors and graft rejection. In recent times, cellular cardiomyoplasty has been expected to repair infarcted myocardium by implantation of different sources of stem or progenitor cells. However, low cell survival and myocardial implantation rates have motivated the emergence of novel approaches with the objective of generating graftable cell-based implants. Here, the potential

  7. Successful Closure of A Bronchopleural Fistula by Intrapleural Administration of Fibrin Sealant: A Case Report With Review of Literature

    PubMed Central

    Shrestha, Pranabh; Safdar, Syed Aatif; Jawad, Sami Abdul; Shaaban, Hamid; Dieguez, Javier; Elberaqdar, Enas; Rai, Srijana; Adelman, Marc

    2014-01-01

    Context: There are no established guidelines for the proper treatment of patients with bronchopleural fistulas (BPFs). Apart from attempts to close the fistula, emphasis of treatment and management is placed on preventive measures, early administration of antibiotics, drainage of the empyema and aggressive nutritional and rehabilitative support. Case Report: A 53-year-old male presented with nausea, vomiting, and dry cough with eventual respiratory failure. He was found to have an empyema of the left hemithorax which was managed with thoracostomy drainage and antibiotics. However, he had persistent air leak through the chest tube due to a BPF. Bronchoscopy failed to localize the involved segment. Application of fibrin glue through the chest tube succeeded in completely sealing the leak. Conclusion: To our knowledge, this is the first case report in which fibrin glue was successfully used intrapleurally to close a BPF related to an empyema. PMID:25317397

  8. Comparison of the effect of aerosolized fibrin sealant and biodegradable synthetic polyurethane foam on hemostasis and wound healing after endoscopic sinus surgery: a prospective randomized study.

    PubMed

    Jung, Moon Sik; Choi, Chang Hwan; Yu, Myeong Sang

    2017-08-31

    Use of absorbable packing materials after functional endoscopic sinus surgery (FESS) is associated with increased patient comfort and a lack of need for packing removal. Different materials may induce different patterns of mucosal healing and hemostasis. This study investigated the effect of fibrin sealant (FS; Tisseel) or biodegradable synthetic polyurethane foam (Nasopore(®) ) packing on hemostasis and wound healing after FESS. This prospective randomized controlled trial included 35 consecutive patients who underwent bilateral FESS for chronic rhinosinusitis. The patients were randomized to receive FS through aerosol spraying on 1 side and Nasopore packing on the opposite side. They were followed at 1, 2, 4, 8, and 12 weeks after surgery. Endoscopically visible packing material, crusting, adhesion, bleeding, granulation tissue formation, frontal sinus patency, and adverse effects were assessed. Subjective symptoms related to nasal packing were evaluated by using questionnaires quantified with a visual analogue scale. No significant differences were found between the FS-treated side and the Nasopore-packed side with respect to postoperative bleeding, adhesion, or frontal sinus patency. However, crusting and granulation were significantly lower in FS-treated nostrils (p < 0.01). The patients' satisfaction and willingness to reuse the material were not significantly different between FS and Nasopore. There were no allergic reactions to either material. FS and Nasopore were equally successful in achieving hemostasis and patient satisfaction after FESS. However, our results suggest that differential mucosal healing patterns may be induced by alternative absorbable hemostatic materials. FS-treated sides showed more optimal healing patterns than Nasopore-packed sides. © 2017 ARS-AAOA, LLC.

  9. Comparison of fibrin sealant and staples for attaching split-thickness autologous sheet grafts in patients with deep partial- or full-thickness burn wounds: a phase 1/2 clinical study.

    PubMed

    Gibran, Nicole; Luterman, Arnold; Herndon, David; Lozano, Daniel; Greenhalgh, David G; Grubbs, Lisa; Schofield, Neil; Hantak, Edith; Callahan, Janice D; Schiestl, Nina; Riina, Louis H

    2007-01-01

    We undertook a multicenter, randomized, controlled, phase 1/2 clinical study to investigate the safety and efficacy of a fibrin sealant containing 4 IU/ml thrombin (FS 4IU) for the attachment of autologous sheet grafts in patients with deep partial-thickness or full-thickness burn wounds. Fibrin sealant (FS 4IU) was compared with staples for adherence of sheet grafts in 40 patients. Patients had to have burn wounds measuring 40% TBSA or less with two comparable test sites measuring between 1% and 4% TBSA each. Wound beds were prepared before treatment assignment, which was randomized. Percent area of hematoma/seroma at Day 1 (P = .0138) and questionable viability at Day 5 (P = .0182) were significantly less for FS 4IU-treated sites. Median percent area of graft survival on Day 14 was 100% for both treatments (P = .3525). The percentage of completely closed sites generally was greater for FS 4IU-sites on Days 5 to 91; the maximum difference occurred at Day 28 (79.5% vs 59%; P = .0215). The safety profile of FS 4IU was excellent as indicated by the lack of any related serious adverse experiences. These findings indicate that FS 4IU is safe and effective for fixation of skin grafts, with outcomes similar to or better than staple fixation. The data suggest that FS 4IU is a promising candidate for further clinical studies focusing on skin graft adhesion and burn wound healing.

  10. Staple Line Coverage with a Polyglycolic Acid Patch and Fibrin Glue without Pleural Abrasion after Thoracoscopic Bullectomy for Primary Spontaneous Pneumothorax

    PubMed Central

    Hong, Ki Pyo; Kim, Do Kyun; Kang, Kyung Hoon

    2016-01-01

    Background This study was conducted to determine the efficacy of staple line coverage using a polyglycolic acid patch and fibrin glue without pleural abrasion to prevent recurrent postoperative pneumothorax. Methods A retrospective analysis was carried out of 116 operations performed between January 2011 and April 2013. During this period, staple lines were covered with a polyglycolic acid patch and fibrin glue in 58 cases (group A), while 58 cases underwent thoracoscopic bullectomy only (group B). Results The median follow-up period was 33 months (range, 22 to 55 months). The duration of chest tube drainage was shorter in group A (group A 2.7±1.2 day vs. group B 3.9±2.3 day, p=0.001). Prolonged postoperative air leakage occurred more frequently in group B than in group A (43% vs. 19%, p=0.005). The postoperative recurrence rate of pneumothorax was significantly lower in group A (8.6%) than in group B (24.1%) (p=0.043). The total cost of treatment during the follow-up period, including the cost for the treatment of postoperative recurrent pneumothorax, was not significantly different between the two groups (p=0.43). Conclusion Without pleural abrasion, staple line coverage with a medium-sized polyglycolic acid patch and fibrin glue after thoracoscopic bullectomy for primary spontaneous pneumothorax is a useful technique that can reduce the duration of postoperative pleural drainage and the postoperative recurrence rate of pneumothorax. PMID:27066431

  11. Efficacy and safety of a fibrin sealant for adherence of autologous skin grafts to burn wounds: results of a phase 3 clinical study.

    PubMed

    Foster, Kevin; Greenhalgh, David; Gamelli, Richard L; Mozingo, David; Gibran, Nicole; Neumeister, Michael; Abrams, Steven Zvi; Hantak, Edith; Grubbs, Lisa; Ploder, Bettina; Schofield, Neil; Riina, Louis H

    2008-01-01

    The objective of this phase 3, multicentered, prospective, randomized, evaluator-blinded, clinical study was to compare skin graft adherence utilizing a fibrin sealant containing 4 IU/ml thrombin (FS 4IU VH S/D [FS 4IU VH S/D will be marketed under the trade name ARTISS upon licensure in the United States]) to graft adherence utilizing staples in burn patients requiring wound excision and skin grafting. FS 4IU VH S/D was compared with staples in 138 patients. Patients had burn wounds measuring < or =40% of total body surface area with two comparable test sites measuring between 1 and 4% total body surface area each. Wound closure at day 28 was assessed using test site planimetry and review of day 28 photographs by three independent blinded evaluators (primary endpoint analysis). Secondary efficacy measures included hematoma/seroma on day 1, engraftment on day 5, and wound closure on day 14. Investigator and patient-reported outcomes were also assessed. The proportion of test sites with complete wound closure at day 28 was 70.3% in FS 4IU VH S/D treated sites and 65.8% in stapled sites, as assessed by planimetry. Blinded review of day 28 photographs confirmed that the rate of complete wound closure was similar between the two treatments, although the overall assessed rates of closure were lower than those determined by planimetry: FS 4IU VH S/D (43.3%) and staples (37.0%). The lower limit of the 97.5% confidence interval of the difference between FS 4IU VH S/D and staples was -0.029, which is above the predefined noninferiority margin of -0.1. Therefore, FS 4IU VH S/D is at least as efficacious as staples at the 97.5% one-sided level for complete wound closure by day 28. Hematoma/seroma on day 1 occurred at significantly (P < .0001) fewer FS 4IU VH S/D-treated sites (29.7% [95% CI 22.2-38.1%]) compared with stapled sites (62.3% [95% CI 53.7-70.4%]). Engraftment on day 5 was deemed to be 100% in 62.3% (95% CI 53.7-70.4%) of the FS 4IU VH S/D-treated sites and 55

  12. A new heterologous fibrin sealant as scaffold to recombinant human bone morphogenetic protein-2 (rhBMP-2) and natural latex proteins for the repair of tibial bone defects.

    PubMed

    Machado, Eduardo Gomes; Issa, João Paulo Mardegan; Figueiredo, Fellipe Augusto Tocchini de; Santos, Geovane Ribeiro Dos; Galdeano, Ewerton Alexandre; Alves, Mariana Carla; Chacon, Erivelto Luis; Ferreira Junior, Rui Seabra; Barraviera, Benedito; Cunha, Marcelo Rodrigues da

    2015-04-01

    Tissue engineering has special interest in bone tissue aiming at future medical applications Studies have focused on recombinant human bone morphogenetic protein-2 (rhBMP-2) and natural latex proteins due to the osteogenic properties of rhBMP-2 and the angiogenic characteristic of fraction 1 protein (P-1) extracted from the rubber tree Hevea brasiliensis. Furthermore, heterologous fibrin sealant (FS) has been shown as a promising alternative in regenerative therapies. The aim of this study was to evaluate these substances for the repair of bone defects in rats. A bone defect measuring 3mm in diameter was created in the proximal metaphysis of the left tibia of 60 rats and was implanted with rhBMP-2 or P-1 in combination with a new heterologous FS derived from snake venom. The animals were divided into six groups: control (unfilled bone defect), rhBMP-2 (defect filled with 5μg rhBMP-2), P-1 (defect filled with 5μg P-1), FS (defect filled with 8μg FS), FS/rhBMP-2 (defect filled with 8μg FS and 5μg rhBMP-2), FS/P-1 (defect filled with 8μg FS and 5μg P-1). The animals were sacrificed 2 and 6 weeks after surgery. The newly formed bone projected from the margins of the original bone and exhibited trabecular morphology and a disorganized arrangement of osteocyte lacunae. Immunohistochemical analysis showed intense expression of osteocalcin in all groups. Histometric analysis revealed a significant difference in all groups after 2 weeks (p<0.05), except for the rhBMP-2 and FS/rhBMP-2 groups (p>0.05). A statistically significant difference (p<0.05) was observed in all groups after 6 weeks in relation to the volume of newly formed bone in the surgical area. In conclusion, the new heterologous fibrin sealant was found to be biocompatible and the combination with rhBMP-2 showed the highest osteogenic and osteoconductive capacity for bone healing. These findings suggest a promising application of this combination in the regeneration surgery.

  13. [Experimental study on application recombinant human bone morphogenetic protein 2(rhBMP-2)/poly-lactide-co-glycolic acid (PLGA)/fibrin sealant(FS) on repair of rabbit radial bone defect].

    PubMed

    Fan, Zhongkai; Cao, Yang; Zhang, Zhe; Zhang, Mingchao; Lu, Wei; Tang, Lei; Yao, Qi; Lu, Gang

    2012-10-01

    This paper is aimed to investigate the repair of rabbit radial bone defect by the recombinant human bone morphogenetic protein 2/poly-lactideco-glycolic acid microsphere with fibrin sealant (rhBMP-2/PLGA/FS). The radial bone defect models were prepared using New Zealand white rabbits, which were randomly divided into 3 groups, experiment group which were injected with eMP-2/PLGA/FS at bone defect location, control group which were injected with FS at bone defect location, and blank control group without treatment. The ability of repairing bone defect was evaluated with X-ray radiograph. Bone mineral density in the defect regions was analysed using the level of ossification. The osteogenetic ability of repairing bone defect, the degradation of the material, the morphologic change and the bone formation were assessed by HE staining and Masson staining. The result showed that rhBMP-2/PLGA/FS had overwhelming superiority in the osteogenetic ability and quality of bone defect over the control group, and it could promote the repair of bone defect and could especially repair the radial bone defect of rabbit well. It may be a promising and efficient synthetic bone graft.

  14. Ocular surface sealants and adhesives.

    PubMed

    Bhatia, Subir Singh

    2006-07-01

    Tissue adhesives, both synthetic and biologic, have a long history of use in ophthalmology. Cyanoacrylate-based glues have traditionally been the most widely used glues for various purposes. They have been specially useful for treating corneal perforations and have had significantly improved long-term outcomes. More recently, fibrin-based glues have gained a major role as a suture substitute for attaching biologic tissues and as surface sealants. The literature supports expanded use of fibrin glue in this fashion. Other new agents, such as polyethyelene glycols, have been underutilized and hold promise, especially as surface protectants. Numerous other glues are being developed and show promise as ocular surface sealants and protective membranes. Advances in knowledge about tissue adhesives are leading to more effective and efficient ophthalmic care.

  15. A dual-institution randomized controlled trial of remnant closure after distal pancreatectomy: does the addition of a falciform patch and fibrin glue improve outcomes?

    PubMed

    Carter, Timothy I; Fong, Zhi Ven; Hyslop, Terry; Lavu, Harish; Tan, Wei Phin; Hardacre, Jeffrey; Sauter, Patricia K; Kennedy, Eugene P; Yeo, Charles J; Rosato, Ernest L

    2013-01-01

    The objective of the study was to assess the efficacy of two pancreatic remnant closure techniques following distal pancreatectomy: (1) stapled or sutured closure versus (2) stapled or sutured closure plus falciform patch and fibrin glue reinforcement in the setting of a prospective randomized trial, with the primary endpoint being pancreatic fistula. Pancreatic stump leak following left-sided pancreatic resection (distal pancreatectomy) remains common. Despite multiple and varied techniques for closure, the reported leak rate varies up to 30 %. A retrospective analysis by Iannitti et al. (J Am Coll Surg 203(6):857-864, 2006) detected a decreased leak rate in patients receiving a traditional closure buttressed with an autologous falciform ligament patch and fibrin glue. Between April 2008 and October 2011, all willing patients scheduled to undergo distal pancreatectomy at the authors' institutions were consented and enrolled at the preoperative office visit. Patients were intraoperatively stratified as having hard or soft glands and randomized to one of two groups: (1) closure utilizing stapling or suturing (SS) versus (2) stapled or sutured plus falciform ligament patch and fibrin glue (FF). The trial design and power analysis (α = 0.05, β = 0.2, power 80 %, chi-square test) hypothesized that the FF intervention would reduce the primary endpoint (pancreatic fistula) from 30 % to 15 % and targeted an accrual goal of 190 patients. Secondary endpoints included length of postoperative hospital stay, 30-day mortality, hospital readmission, and ISGPF fistula grade (A, B, and C). The trial accrued 109 patients, 55 in the SS group and 54 in the FF group. Enrollment was closed prior to the target accrual, following an interim analysis and futility calculation. Due to insufficient enrollment, patients stratified as having a hard gland were excluded (n = 8) from analysis, leaving 101 patients in the soft stratum. The overall pancreatic leak rate was 19.8

  16. Dental sealants

    MedlinePlus

    ... few quick steps. There is no drilling or scraping of the molars. Your dentist will: Clean the ... Dental sealants. Updated October 19, 2016. ADA.org Web site. www.ada.org/en/member-center/oral- ...

  17. Lendrum (-MSB) staining for fibrin identification in sealed skin grafts.

    PubMed

    Fisseler-Eckhoff, A; Müller, K M

    1994-05-01

    The significance and effect of fibrin sealant systems for woundhealing are still unknown, because of the use of insufficient, conventional staining methods for the demonstration of the fibrin components used by sealant systems. From 21 patients with extensive burns of 2nd and 3rd degree biopsies of the skin were obtained during consecutive operations to cover the defect of the skin with split-thickness skin grafting. In the present paper morphological results concerning the demonstration of fibrin components and morphological differences in woundhealing of sealed and unsealed skin grafts are presented using Lendrum (-MSB) staining. With this staining method it is possible to identify exogenous fibrin components of the sealant system and to differentiate between fresh and older fibrin components, due to colour changes depending on time.

  18. New method to prepare autologous fibrin glue on demand.

    PubMed

    Alston, Steven M; Solen, Kenneth A; Broderick, Adam H; Sukavaneshvar, Sivaprasad; Mohammad, S Fazal

    2007-04-01

    Fibrin-based sealants are commonly employed to arrest bleeding after surgery. Usually, fibrinogen obtained from pooled human plasma is used to prepare sealants, with attendant risk of blood-borne infections. Availability of autologous fibrinogen would eliminate this risk. To prepare autologous fibrin sealant, fibrinogen was precipitated from human plasma using protamine. Under optimal conditions (10-mg/mL protamine and 22 degrees C), 96 +/- 4% of clottable fibrinogen was recovered by a simple and inexpensive technique. Nearly 50% of the plasma factor XIII was also recovered with the fibrinogen. Using bovine thrombin, the fibrinogen was clotted (1) in a specially designed mold to measure tensile strength and (2) in a lap joint between 2 aortic vessel strips to measure adhesion strength. Tensile and adhesion strengths increased with increasing fibrinogen concentration, and they were increased by the addition of calcium chloride. The addition of aprotinin and -aminocaproic acid to the fibrinogen concentrate before clotting had no effect on the mechanical properties of the clots. After adding thrombin to sealant containing 15-mg/mL fibrinogen, maximum tensile strength was achieved in 1-5 min, and maximum adhesion strength was reached in 5-15 min. For the sealant with 30-60-mg/mL fibrinogen and added calcium, the tensile strength was equivalent to that of the commercial fibrin sealant Tisseel. The adhesion strength of sealant with 30-60-mg/mL fibrinogen exceeded the adhesive strength of Tisseel under identical conditions. Autologous fibrin sealant is an attractive alternative to commercial sealants. It can be readily prepared from 5-mL plasma or more and exhibits mechanical properties equivalent to those of the leading commercial sealant.

  19. Dental Sealants Prevent Cavities

    MedlinePlus

    ... centers, and dental providers in the community to foster more use of sealants and reimbursement of services. Dental care providers can Apply sealants to children at highest risk of cavities, including those covered ...

  20. Failure mechanisms of fibrin-based surgical tissue adhesives

    NASA Astrophysics Data System (ADS)

    Sierra, David Hugh

    A series of studies was performed to investigate the potential impact of heterogeneity in the matrix of multiple-component fibrin-based tissue adhesives upon their mechanical and biomechanical properties both in vivo and in vitro. Investigations into the failure mechanisms by stereological techniques demonstrated that heterogeneity could be measured quantitatively and that the variation in heterogeneity could be altered both by the means of component mixing and delivery and by the formulation of the sealant. Ex vivo tensile adhesive strength was found to be inversely proportional to the amount of heterogeneity. In contrast, in vivo tensile wound-closure strength was found to be relatively unaffected by the degree of heterogeneity, while in vivo parenchymal organ hemostasis in rabbits was found to be affected: greater heterogeneity appeared to correlate with an increase in hemostasis time and amount of sealant necessary to effect hemostasis. Tensile testing of the bulk sealant showed that mechanical parameters were proportional to fibrin concentration and that the physical characteristics of the failure supported a ductile mechanism. Strain hardening as a function of percentage of strain, and strain rate was observed for both concentrations, and syneresis was observed at low strain rates for the lower fibrin concentration. Blister testing demonstrated that burst pressure and failure energy were proportional to fibrin concentration and decreased with increasing flow rate. Higher fibrin concentration demonstrated predominately compact morphology debonds with cohesive failure loci, demonstrating shear or viscous failure in a viscoelastic rubbery adhesive. The lower fibrin concentration sealant exhibited predominately fractal morphology debonds with cohesive failure loci, supporting an elastoviscous material condition. The failure mechanism for these was hypothesized and shown to be flow-induced ductile fracture. Based on these findings, the failure mechanism was

  1. Enhanced Sealing by Hydrophobic Modification of Alaska Pollock-Derived Gelatin-Based Surgical Sealants for the Treatment of Pulmonary Air Leaks.

    PubMed

    Mizuta, Ryo; Taguchi, Tetsushi

    2016-11-15

    Pulmonary air leaks are medical complications of thoracic surgery for which fibrin sealant is the main treatment. In this study, innovative sealants based on hydrophobically modified Alaska pollock-derived gelatin (hm-ApGltn) and a poly(ethylene)glycol-based 4-armed cross-linker (4S-PEG) have been developed and their burst strengths have been evaluated using fresh rat lung. The developed sealants show higher lung burst strength compared with the nonmodified original ApGltn (Org-ApGltn)-based sealant and a commercial fibrin sealant. The maximum burst strength of the hm-ApGltn-based sealant is 1.6-fold higher than the Org-ApGltn-based sealant (n = 5, p < 0.05), and 2.1-fold higher than the commercial fibrin sealant (n = 5, p < 0.05). Cell culture experiments show that modification of ApGltn with cholesteryl or stearoyl groups effectively enhances anchoring to the cell surface. In addition, binding constants between hm-ApGltn and extracellular matrix proteins such as fibronectin and fibrillin are increased. Therefore, the new hm-ApGltn/4S-PEG-based sealant has the potential for applications in thoracic surgery.

  2. Salmon fibrin glue in rats: antibody studies.

    PubMed

    Laidmäe, Ivo; Belozjorova, Jevgenia; Sawyer, Evelyn S; Janmey, Paul A; Uibo, Raivo

    2012-01-01

    Fibrin sealants and topical thrombin preparations are often used for haemostatic and sealing applications in clinical practice. Some of these preparations contain coagulation factors from bovine sources. To minimize the risk of infection and immunogenicity connected with mammalian blood products, proteins derived from the plasma of farmed Atlantic salmon have been considered as an alternative to these mammalian sources. The purpose of this study is to characterize the immunogenicity of salmon fibrin glue in an animal model focusing on crossreactivity of IgG antibodies to host endogenous counterparts. After two immunizations with salmon fibrin glue, rats developed antibodies of IgG and IgM type to both fibrin glue components. Weak crossreactivity to endogenous fibrinogen and thrombin was seen in a subset of rats after the second application of salmon proteins. Coagulation tests showed that salmon fibrin application has no effect on coagulation profiles in mammalian hosts, consistent with previous reports that found no evidence of significant crossreactivity with host proteins. These studies support the potential suitability of salmon fibrin glue for the development of preparations with clinical impact. Before human use can be considered, however, additional data about safety of this preparation in other animal models, including large animal studies, should be obtained.

  3. Behavior of human dermal fibroblasts in three-dimensional fibrin clots: dependence on fibrinogen and thrombin concentration.

    PubMed

    Cox, Steve; Cole, Marietta; Tawil, Bill

    2004-01-01

    Fibrin sealant products are used in hemostasis and tissue sealing, and potentially as a cell delivery vehicle. In this study, fibrin sealant was evaluated as a delivery vehicle for human dermal fibroblasts. Fibroblast proliferation and migration were assessed in various dilutions of fibrin sealant by changing the fibrinogen and thrombin concentration. Fibroblasts proliferated well within three-dimensional (3-D) fibrin clots consisting of fibrinogen (5-17 mg/mL) and thrombin (1-167 U/mL). These fibroblasts also retained good morphology and growth characteristics after migrating out of the 3-D fibrin clots. Furthermore, using Western blot and fluorescence-activated cell-sorting analysis, we found that the expression of growth factors and interleukins in the entire fibroblast-fibrin construct was dependent on the fibrin sealant formulation. For example, in a formulation in which fibroblasts showed modest proliferation and migration, interleukin 8 was secreted to a lesser extent than in a formulation that supported robust proliferation and migration. To our knowledge, this is the first time that it has been shown that modifying the concentration of fibrinogen and thrombin affects fibroblast behavior within formed 3-D fibrin clots. In addition, some of these formulations present an ideal delivery vehicle for fibroblasts that could be used for the treatment of chronic wounds.

  4. The use of hemostatic agents and sealants in urology.

    PubMed

    Hong, Y Mark; Loughlin, Kevin R

    2006-12-01

    While hemostatic agents and sealants have long been used in the fields of surgery and urology, confusion persists about their indications for use and the optimal agent choice. We comprehensively defined and evaluated the scientific basis for hemostatic agent and sealant use in urology, and provide a conceptual framework for future research and discussion. A MEDLINE search of all available literature concerning hemostatic agents in urology was performed, including topical hemostats, anti-fibrinolytics, fibrin sealants and matrix hemostats. Select references were also chosen from the broader surgical literature. Animal studies, case reports, retrospective and prospective studies, and opinion articles were reviewed. Hemostatic agents include a wide range of components. Recent literature has focused on fibrin sealants and matrix agents. Two main indications exist for hemostatic agents, including 1) hemostasis and 2) sealant. The best evidence for efficacy and safety exists for hemostasis, especially for nephrectomy and trauma. Newer data highlight urinary tract reconstruction, fistula and percutaneous tract closure, suture line strengthening and infertility as potential uses. Novel drug delivery and tissue engineering are areas with large clinical potential. Hemostatic agent use is promising and yet unproven for most conditions currently treated in urology. Hemostasis continues to be the main indication, which is well established. Few trials have examined comparative efficacy among hemostatic agents and further prospective studies are needed to justify additional indications as well as determine the optimal mode of use. Minimally invasive surgery will further drive the use of hemostatic agents and sealants. Cost-effective, evidence based hemostatic agent use will continue to challenge all urologists.

  5. Structural basis for the nonlinear mechanics of fibrin networks under compression

    PubMed Central

    Kim, Oleg V.; Litvinov, Rustem I.; Weisel, John W.; Alber, Mark S.

    2014-01-01

    Fibrin is a protein polymer that forms a 3D filamentous network, a major structural component of protective physiological blood clots as well as life threatening pathological thrombi. It plays an important role in wound healing, tissue regeneration and is widely employed in surgery as a sealant and in tissue engineering as a scaffold. The goal of this study was to establish correlations between structural changes and mechanical responses of fibrin networks exposed to compressive loads. Rheological measurements revealed nonlinear changes of fibrin network viscoelastic properties under dynamic compression, resulting in network softening followed by its dramatic hardening. Repeated compression/decompression enhanced fibrin clot stiffening. Combining fibrin network rheology with simultaneous confocal microscopy provided direct evidence of structural modulations underlying nonlinear viscoelasticity of compressed fibrin networks. Fibrin clot softening in response to compression strongly correlated with fiber buckling and bending, while hardening was associated with fibrin network densification. Our results suggest a complex interplay of entropic and enthalpic mechanisms accompanying structural changes and accounting for the nonlinear mechanical response in fibrin networks undergoing compressive deformations. These findings provide new insight into the fibrin clot structural mechanics and can be useful for designing fibrin-based biomaterials with modulated viscoelastic properties. PMID:24840618

  6. Structural basis for the nonlinear mechanics of fibrin networks under compression.

    PubMed

    Kim, Oleg V; Litvinov, Rustem I; Weisel, John W; Alber, Mark S

    2014-08-01

    Fibrin is a protein polymer that forms a 3D filamentous network, a major structural component of protective physiological blood clots as well as life threatening pathological thrombi. It plays an important role in wound healing, tissue regeneration and is widely employed in surgery as a sealant and in tissue engineering as a scaffold. The goal of this study was to establish correlations between structural changes and mechanical responses of fibrin networks exposed to compressive loads. Rheological measurements revealed nonlinear changes of fibrin network viscoelastic properties under dynamic compression, resulting in network softening followed by its dramatic hardening. Repeated compression/decompression enhanced fibrin clot stiffening. Combining fibrin network rheology with simultaneous confocal microscopy provided direct evidence of structural modulations underlying nonlinear viscoelasticity of compressed fibrin networks. Fibrin clot softening in response to compression strongly correlated with fiber buckling and bending, while hardening was associated with fibrin network densification. Our results suggest a complex interplay of entropic and enthalpic mechanisms accompanying structural changes and accounting for the nonlinear mechanical response in fibrin networks undergoing compressive deformations. These findings provide new insight into the fibrin clot structural mechanics and can be useful for designing fibrin-based biomaterials with modulated viscoelastic properties.

  7. Advanced supersonic technology fuel tank sealants

    NASA Technical Reports Server (NTRS)

    Rosser, R. W.; Parker, J. A.

    1976-01-01

    Status of the fuel tank simulation and YF-12A flight tests utilizing a fluorosilicone sealant is described. New elastomer sealant development is detailed, and comparisons of high and low temperature characteristics are made to baseline fluorosilicone sealants.

  8. Microvascular anastomosis using fibrin glue and venous cuff in rat carotid artery.

    PubMed

    Sacak, Bulent; Tosun, Ugur; Egemen, Onur; Sakiz, Damlanur; Ugurlu, Kemal

    2015-04-01

    Conventional anastomosis with interrupted sutures can be time-consuming, can cause vessel narrowing, and can lead to thrombosis at the site of repair. The amount of suture material inside the lumen can impair the endothelium of the vessel, triggering thrombosis. In microsurgery, fibrin sealants have the potential beneficial effects of reducing anastomosis time and promoting accurate haemostasis at the anastomotic site. However, there has been a general reluctance to use fibrin glue for microvascular anastomoses because the fibrin polymer is highly thrombogenic and may not provide adequate strength. To overcome these problems, a novel technique was defined for microvascular anastomosis with fibrin glue and a venous cuff. Sixty-four rats in two groups are included in the study. In the experimental group (n = 32), end-to-end arterial anastomosis was performed with two stay sutures, fibrin glue, and a venous cuff. In the control group (n = 32), conventional end-to-end arterial anastomosis was performed. Fibrin glue assisted anastomosis with a venous cuff took less time, caused less bleeding at the anastomotic site, and achieved a patency rate comparable to that provided by the conventional technique. Fibrin sealant assisted microvascular anastomosis with venous cuff is a rapid, easy, and reliable technique compared to the end-to-end arterial anastomosis.

  9. Novel synthetic adhesive as an effective alternative to Fibrin based adhesives.

    PubMed

    Srinivasan, Pramod Kadaba; Sperber, Vera; Afify, Mamdouh; Tanaka, Hirokazu; Fukushima, Kenji; Kögel, Babette; Gremse, Felix; Tolba, René

    2017-08-28

    To compare a novel, fully synthetic, polyurethane based glue (MAR-1) to fibrin sealant in a partial liver resection rat model. After 50% resection of the lateral left liver lobe in male Wistar rats (n = 7/group/time point), MAR-1, Fibrin or NaCl was applied. After 14, 21 and 90 postoperative days, sealant degradation, intra-abdominal adhesions were scored, and histological examination of liver tissue was performed. (Mean ± SEM) (MAR-1 vs Fibrin vs NaCl). Bleeding mass was significantly higher in NaCl (3.36 ± 0.51 g) compared to MAR-1 (1.44 ± 0.40 g) and Fibrin (1.16 ± 0.32 g). At 14 and 90 d, bleeding time was significantly lower in MAR-1 (6.00 ± 0.9 s; 13.57 ± 3.22 s) and Fibrin (3.00 ± 0.44 s; 22.2 ± 9.75 s) compared to NaCl (158.16 ± 11.36 s; 127.5 ± 23.3 s). ALT levels were significantly higher in MAR-1 (27.66 ± 1 U/L) compared to Fibrin (24.16 ± 0.98 U/L) and NaCl (23.85 ± 0.80 U/L). Intrabdominal adhesions were significantly lower in MAR-1 (11.22% ± 5.5%) compared to NaCl (58.57% ± 11.83%). Degradation of the glue was observed and MAR-1 showed almost no traces of glue in the abdominal cavity as compared to the Fibrin (10% ± 5% 14 d; 7% ± 3% 21 d). Survival showed no significant differences between the groups. Compared to Fibrin, MAR-1 showed similar hemostatic properties, no adverse effects, and is biocompatible. Further studies on adhesion strength and biodegradability of synthetic sealants are warranted.

  10. Fibrin sealing versus stapling of hernia meshes in an onlay model in the rat.

    PubMed

    Petter-Puchner, Alexander H; Fortelny, R; Mittermayr, R; Ohlinger, W; Redl, H

    2005-12-01

    Incisional and inguinal hernia repair are among the most common procedures of general surgery. Mesh fixation by means of staples or sutures may lead to severe complications. The use of fibrin sealant (FS) has been suggested as alternative, but data on biocompatibility and adhesive strength of FS in combination with macroporous meshes is limited. Ventral hernia (n = 8 per group) was treated in rats in onlay technique with two types of meshes, fibrin sealed or stapled. TI-Mesh (TMxl) extralight and VYPROII (VPII) were tested 17 days post op. No failure in mechanical tests (tensile and burst strength) occurred in sealed or stapled meshes. Histology revealed equally good tissue integration and neovascularization in all groups. Fibrin sealant yields excellent fixation in experimental hernia repair. This rat model is suitable for testing meshes and fixation techniques.

  11. Replacement Non-Toxic Sealants for Standard Chromated Sealants

    DTIC Science & Technology

    2005-02-01

    install fasteners, overcoat fasteners, and fillet seal seams. The sealants industry has been researching and developingnew chrome replacement products ...Dayton Research Laboratory (UDRI), and Products Research Corp. (PRC). AFRL was the principle investigator; PRC formulated the sealants; UDRI, NAWC...After a number of prototype formulations were developed and tested, the best formulation was tested and qualified to both military and industry standards

  12. Durability of building joint sealants

    Treesearch

    Christopher C. White; Kar Tean Tan; Donald L. Hunston; R. Sam Williams

    2009-01-01

    Predicting the service life of building joint sealants exposed to service environments in less than real time has been a need of the sealant community for many decades. Despite extensive research efforts to design laboratory accelerated tests to duplicate the failure modes occurring in field exposures, little success has been achieved using conventional durability...

  13. New Joint Sealants. Criteria, Design and Materials.

    ERIC Educational Resources Information Center

    Building Research Inst., Inc., Washington, DC.

    Contents include--(1) sealing concrete joints, (2) sealing glass and metal joints, (3) metal and glass joint sealants from a fabricator's viewpoint, (4) a theory of adhesion for joint sealants, (5) geometry of simple joint seals under strain, (6) joint sealant specifications from a manufacturer's viewpoint, (7) joint sealant requirements from an…

  14. The use of surgical sealants in the repair of dural tears during non-instrumented spinal surgery.

    PubMed

    Miscusi, Massimo; Polli, Filippo Maria; Forcato, Stefano; Coman, Maria Antoaneta; Ricciardi, Luca; Ramieri, Alessandro; Raco, Antonino

    2014-08-01

    To compare the success in repair of dural tears (DTs) using two different surgical sealants in non-instrumented lumbar spinal surgery and evaluate the incidence of associated short- and long-term complications. Twenty-three patients undergoing non-instrumented spinal surgery with intraoperative DTs were included both retrospectively and prospectively in this study. External signs of CSF leakage, neurological deficits, and infection-related complications were investigated postoperatively. The persistence of low-back pain was also evaluated and postoperative MRI was performed in all patients. DTs were repaired intraoperatively using suture with or without a dural patch. Eleven patients received an application of fibrin glue (Tissucol(®); Baxter, Inc., IL, USA) and 12 patients received an application of bovine serum albumin glutaraldehyde surgical adhesive (BioGlue(®) Surgical Adhesive; CryoLife, GA, USA). These patients were followed up at 3 months and 1 year postoperatively. Successful intraoperative DT repair was obtained in all cases. Three patients in the Tissucol group presented with CSF leakage in the early postoperative period. There were no complications observed in the patients treated with BioGlue. At 3-month follow-up, no incidences of neurological or infection-related complications were observed in either group. There was no statistically significant difference in VAS between the two treatment groups. Intraoperative DTs can be easily repaired by many effective techniques. However, in our experience, the use of BioGlue is an effective adjunct to immediate dural repair, being comparable in terms of efficacy and safety to the use of fibrin glue, potentially decreasing the incidence of associated short- and long-term complications.

  15. Does tranexamic acid stabilised fibrin support the osteogenic differentiation of human periosteum derived cells?

    PubMed

    Demol, J; Eyckmans, J; Roberts, S J; Luyten, F P; Van Oosterwyck, H

    2011-03-22

    Fibrin sealants have long been used as carrier for osteogenic cells in bone regeneration. However, it has not been demonstrated whether fibrin's role is limited to delivering cells to the bone defect or whether fibrin enhances osteogenesis. This study investigated fibrin's influence on the behaviour of human periosteum-derived cells (hPDCs) when cultured in vitro under osteogenic conditions in two-dimensional (fibrin substrate) and three-dimensional (fibrin carrier) environments. Tranexamic acid (TEA) was used to reduce fibrin degradation after investigating its effect on hPDCs in monolayer culture on plastic.TEA did not affect proliferation nor calcium deposition of hPDCs under these conditions. Expression profiles of specific osteogenic markers were also maintained within the presence of TEA, apart from reduced alkaline phosphatase (ALP) expression (day 14). Compared to plastic, proliferation was upregulated on 2D fibrin substrates with a 220% higher DNA content by day 21. Gene expression was also altered, with significantly (p<0.05) decreased Runx2 (day 7) and ALP (day 14) expression and increased collagen I expression (day 14 and 21). In contrast to plastic, mineralisation was absent on fibrin substrates. Inside fibrin carriers, hPDCs were uniformly distributed. Moderate cell growth and reduced osteogenic marker expression was observed inside fibrin carriers. After 2 weeks, increased cell death was present in the carrier's centre. In conclusion, fibrin negatively influences osteogenic differentiation, compared to culture plastic, but enhanced proliferation (at least in 2D cultures) for hPDCs cultured in osteogenic conditions. TEA maintained the integrity of fibrin-based constructs, with minor effects on the osteogenic differentiation of hPDCs.

  16. [Pterygium surgery and fibrin glue: avoiding dehiscence].

    PubMed

    Pérez-Silguero, D; Díaz-Ginory, A; Santana-Rodríguez, C; Pérez-Silguero, M A

    2014-01-01

    The purpose of the study is to evaluate those cases of pterygium surgery with fibrin sealant that produced dehiscence of the graft, and then apply and evaluate the efficacy of a different surgical technique in an attempt eliminate this complication in previously identified cases of high risk. The first phase is a retrospective study of 42 cases of pterygium surgery. In the second phase, the variation in the surgical technique was prospectively used in 14 cases of pterygium surgery. Cases of recurrent pterygium, broad pterygium, and complicated surgery were identified as the groups with a risk of suffering dehiscence of the graft. With the variant applied surgery no dehiscence occurred when using the variation in surgical technique, with no added complications. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  17. Elastic sealants for surgical applications.

    PubMed

    Annabi, Nasim; Yue, Kan; Tamayol, Ali; Khademhosseini, Ali

    2015-09-01

    Sealants have emerged as promising candidates for replacing sutures and staples to prevent air and liquid leakages during and after the surgeries. Their physical properties and adhesion strength to seal the wound area without limiting the tissue movement and function are key factors in their successful implementation in clinical practice. In this contribution, the advances in the development of elastic sealants formed from synthetic and natural materials are critically reviewed and their shortcomings are pointed out. In addition, we highlight the applications in which elasticity of the sealant is critical and outline the limitations of the currently available sealants. This review will provide insights for the development of novel bioadhesives with advanced functionality for surgical applications.

  18. Effect of alkyl chain length on the interfacial strength of surgical sealants composed of hydrophobically-modified Alaska-pollock-derived gelatins and poly(ethylene)glycol-based four-armed crosslinker.

    PubMed

    Mizuta, Ryo; Ito, Temmei; Taguchi, Tetsushi

    2016-10-01

    Surgical sealants are widely used clinically. Fibrin sealant is a commonly used sealant, but is ineffective under wet conditions during surgery. In this study, we developed surgical sealants composed of hydrophobically modified Alaska-pollock-derived gelatins (hm-ApGltns) with different alkyl chain lengths from C3 to C18 and a poly(ethylene)glycol-based 4-armed crosslinker (4S-PEG). The burst strength of the hm-ApGltns-based sealant was evaluated using a fresh porcine blood vessel and was found to increase with increasing alkyl chain length from 167±22 to 299±43mmHg when the substitution ratio of amino groups of ApGltn was around 10mol%. The maximum burst strength was observed when stearoyl-group modified ApGltn (Ste-ApGltn)/4S-PEG-based sealant was used, displaying 3-fold higher burst strength than the original ApGltn (Org-ApGltn)/4S-PEG sealant, and 10-fold higher than the commercial fibrin sealant. Ste-ApGltn/4S-PEG-based sealant was biodegraded in rat subcutaneous tissue within 8 weeks without severe inflammation. By molecular interaction analysis using surface plasmon resonance, the binding constant of Ste-ApGltn to fibronectin was found to be 9-fold higher than that of Org-ApGltn. Therefore, the developed sealant, in particular the Ste-ApGltn/4S-PEG-based sealant, has potential applications in the field of cardiovascular surgery as well as thoracic surgery. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Chemical research projects office fuel tank sealants review. [flight testing of fluorosilicone sealants

    NASA Technical Reports Server (NTRS)

    Rosser, R. W.; Parker, J. A.

    1974-01-01

    The status of high-temperature fuel tank sealants for military and potentially commercial supersonic aircraft is examined. The interrelationships of NASA's sealants program comprise synthesis and development of new fluoroether elastomers, sealant prediction studies, flight simulation and actual flight testing of best state-of-the-art fluorosilicone sealants. The technical accomplishments of these projects are reviewed.

  20. [Healing of tubal anastomoses--microsurgery vs. fibrin gluing: morphologic aspects].

    PubMed

    Gauwerky, J F; Klose, R P; Forssmann, W G

    1994-01-01

    The healing of anastomoses either by microsurgical suture technique or by fibrin sealant technique has been examined in an experimental morphological study. With view to morphological criteria the healing of tubal anastomoses after one month is completed. Afterwards only little areas of regeneration could be found in the region of the anastomosis. These statements are valid for both types of anastomoses. In single cases a more progressive regeneration of the mucosa could be demonstrated. Using fibrin glue a more pronounced fibrosis could not be seen.

  1. Genipin-crosslinked fibrin hydrogels as a potential adhesive to augment intervertebral disc annulus repair.

    PubMed

    Schek, R M; Michalek, A J; Iatridis, J C

    2011-04-18

    Treatment of damaged intervertebral discs is a significant clinical problem and, despite advances in the repair and replacement of the nucleus pulposus, there are few effective strategies to restore defects in the annulus fibrosus. An annular repair material should meet three specifications: have a modulus similar to the native annulus tissue, support the growth of disc cells, and maintain adhesion to tissue under physiological strain levels. We hypothesized that a genipin crosslinked fibrin gel could meet these requirements. Our mechanical results showed that genipin crosslinked fibrin gels could be created with a modulus in the range of native annular tissue. We also demonstrated that this material is compatible with the in vitro growth of human disc cells, when genipin:fibrin ratios were 0.25:1 or less, although cell proliferation was slower and cell morphology more rounded than for fibrin alone. Finally, lap tests were performed to evaluate adhesion between fibrin gels and pieces of annular tissue. Specimens created without genipin had poor handling properties and readily delaminated, while genipin crosslinked fibrin gels remained adhered to the tissue pieces at strains exceeding physiological levels and failed at 15-30%. This study demonstrated that genipin crosslinked fibrin gels show promise as a gap-filling adhesive biomaterial with tunable material properties, yet the slow cell proliferation suggests this biomaterial may be best suited as a sealant for small annulus fibrosus defects or as an adhesive to augment large annulus repairs. Future studies will evaluate degradation rate, fatigue behaviors, and long-term biocompatibility.

  2. Cell culture in autologous fibrin scaffolds for applications in tissue engineering.

    PubMed

    de la Puente, Pilar; Ludeña, Dolores

    2014-03-10

    In tissue engineering techniques, three-dimensional scaffolds are needed to adjust and guide cell growth and to allow tissue regeneration. The scaffold must be biocompatible, biodegradable and must benefit the interactions between cells and biomaterial. Some natural biomaterials such as fibrin provide a structure similar to the native extracellular matrix containing the cells. Fibrin was first used as a sealant based on pools of commercial fibrinogen. However, the high risk of viral transmission of these pools led to the development of techniques of viral inactivation and elimination and the use of autologous fibrins. In recent decades, fibrin has been used as a release system and three-dimensional scaffold for cell culture. Fibrin scaffolds have been widely used for the culture of different types of cells, and have found several applications in tissue engineering. The structure and development of scaffolds is a key point for cell culture because scaffolds of autologous fibrin offer an important alternative due to their low fibrinogen concentrations, which are more suitable for cell growth. With this review our aim is to follow methods of development, analyze the commercial and autologous fibrins available and assess the possible applications of cell culture in tissue engineering in these three-dimensional structures.

  3. Generation of a Fibrin Based Three-Layered Skin Substitute.

    PubMed

    Kober, Johanna; Gugerell, Alfred; Schmid, Melanie; Kamolz, Lars-Peter; Keck, Maike

    2015-01-01

    A variety of skin substitutes that restore epidermal and dermal structures are currently available on the market. However, the main focus in research and clinical application lies on dermal and epidermal substitutes whereas the development of a subcutaneous replacement (hypodermis) is often disregarded. In this study we used fibrin sealant as hydrogel scaffold to generate a three-layered skin substitute. For the hypodermal layer adipose-derived stem cells (ASCs) and mature adipocytes were embedded in the fibrin hydrogel and were combined with another fibrin clot with fibroblasts for the construction of the dermal layer. Keratinocytes were added on top of the two-layered construct to form the epidermal layer. The three-layered construct was cultivated for up to 3 weeks. Our results show that ASCs and fibroblasts were viable, proliferated normally, and showed physiological morphology in the skin substitute. ASCs were able to differentiate into mature adipocytes during the course of four weeks and showed morphological resemblance to native adipose tissue. On the surface keratinocytes formed an epithelial-like layer. For the first time we were able to generate a three-layered skin substitute based on a fibrin hydrogel not only serving as a dermal and epidermal substitute but also including the hypodermis.

  4. Introduction of a potent single-donor fibrin glue for vascular anastomosis: An animal study

    PubMed Central

    Ardakani, Mehdi Rasti; Hormozi, Abdoljalil Kalantar; Ardakani, Jalal Rasti; Davarpanahjazi, Amir Hossein; Moghadam, Ali Shayesteh

    2012-01-01

    Background: Vascular anastomosis is considered as a difficult surgical procedure. Although different alternative methods have been tried to tackle these difficulties, none were found to be successful. Commercial fibrin glue has recently been used for vascular anastomosis. However, it did not gain popularity due to some limitations such as low tensile strength, rapid removal by the immune system, and risk of transmission of blood-borne viral infections. In this article, we presented a novel method for producing single-donor human fibrin glue and determined its success rate for vascular anastomosis in an animal model. Materials ans Methods: In this study, 3 mL of single-donor fibrin sealant was prepared from 150 mL of whole blood containing 50-70 mg/mL of fibrinogen. The study was performed on 10 dogs and 5 cats. After transection of the carotid artery, both ends were anastomosed by means of 3-4 sutures (Prolene 8-0). The suture line was then sealed with one layer of the new fibrin sealant. After 3-8 weeks, the site of anastomosis was evaluated angiographically and morphologically for healing and possible complications such as thrombosis or aneurysm. Results: In evaluations 3 weeks after the surgery, all arterial anastomoses were patent in dogs, but some degree of subintimal hyperplasia was noted. After 8 weeks, all anastomoses were patent and the degree of subintimal hyperplasia was decreased. In cats on the other hand, after 4 weeks, all anastomoses were patent and subintimal hyperplasia was absent. Conclusions: Single-donor fibrin glue was a quite reliable and practical alternative to minimize suturing and therefore operative time in our animal model. This sealant can easily be obtained from the patient's whole blood. Its application in humans would require further studies. PMID:23626612

  5. Solution blow spun polymer: A novel preclinical surgical sealant for bowel anastomoses.

    PubMed

    Kern, Nora G; Behrens, Adam M; Srinivasan, Priya; Rossi, Christopher T; Daristotle, John L; Kofinas, Peter; Sandler, Anthony D

    2017-08-01

    Solution blow spinning is a technique for depositing polymer fibers with promising potential use as a surgical sealant. This study assessed the feasibility and efficacy of solution blow spun polymer (BSP) for sealing bowel perforations in a mouse model of partial cecal transection. We then evaluated its use for reinforcing a surgical anastomosis in a preclinical piglet model. Three commercially available surgical sealants (fibrin glue, polyethylene glycol (PEG) hydrogel, and cyanoacrylate) were compared to BSP in the ability to seal partially transected cecum in mice. For anastomosis feasibility testing in a piglet model, piglets were subjected to small bowel transection with sutured anastomosis reinforced with BSP application. Outcome measures included anastomotic burst pressure, anastomotic leak rate, 14-day survival, and complication rate. For the mouse model, the survival rates for the sealants were 30% for fibrin glue, 20% for PEG hydrogel, 78% for cyanoacrylate, and 67% for BSP. Three of 9 mice died after BSP administration because of perforation leak, failure to thrive with partial obstruction at the perforation site, and unknown causes. All other mice died of perforation leak. The mean burst pressure at 24h was significantly higher for BSP (81mm Hg) when compared to fibrin glue (6mm Hg, p=0.047) or PEG hydrogel (10mm Hg, p=0.047), and comparable to cyanoacrylate (64mm Hg, p=0.91). For piglets, 4 of 4 animals survived at 14days. Mean burst pressures at time of surgery were 37±5mm Hg for BSP and 11±9mm Hg for suture-only controls (p=0.09). Solution blow spinning may be an effective technique as an adjunct for sealing of gastrointestinal anastomosis. Further preclinical testing is warranted to better understand BSP properties and alternative surgical applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. [Fissure sealants--5 years of use].

    PubMed

    Azul, A M

    1990-01-01

    This study assesses the caries prevalence, retention and cost-effectiveness of a pit and fissure sealant in a children population with 622 cases, 5 years after a single application of an auto-polymerized sealant to permanent molars. The status of the sealant and the presence of caries or restaurations on the sealed teeth was assessed. In a self-controlled group of children, the prevalence of disease (caries and restaurations) was also assessed in non-sealed teeth, for comparison. The sealant application was compared with Class I-restauration with amalgam for cost-effectiveness analysis.

  7. Human Adipose Stromal Vascular Cell Delivery in a Fibrin Spray

    PubMed Central

    Zimmerlin, Ludovic; Rubin, J. Peter; Pfeifer, Melanie E.; Moore, L.R.; Donnenberg, Vera S.; Donnenberg, Albert D.

    2014-01-01

    Background Adipose tissue represents a practical source of autologous mesenchymal stromal cells (MSC) and vascular-endothelial progenitor cells, available for regenerative therapy without in vitro expansion. One of the problems confronting the therapeutic application of such cells is how to immobilize them at the wound site. Here, we evaluated in vitro the growth and differentiation of human adipose stromal vascular fraction (SVF) cells after delivery using a fibrin spray system. Methods SVF cells were harvested from four human adult patients undergoing elective abdominoplasty using the LipiVage™ system. After collagenase digestion, mesenchymal and endothelial progenitor cells (pericytes, supra-adventitial stromal cells, endothelial progenitors) were quantified by flow cytometry before culture. SVF cells were applied to culture vessels using the Tisseel™ fibrin spray system. SVF cell growth and differentiation was documented by immunofluorescence staining and photomicrography. Results SVF cells remained viable following application and were expanded up to three weeks, when they reached confluence and adipogenic differentiation. Under angiogenic conditions, SVF cells formed endothelial (vWF+, CD31+ and CD34+) tubules surrounded by CD146+ and α-SMA+ perivascular/stromal cells. Discussion Human adipose tissue is a rich source of autologous stem cells, which are readily available for regenerative applications such as wound healing, without in vitro expansion. Our results indicate that mesenchymal and endothelial progenitor cells, prepared in a closed system from unpassaged lipoaspirate samples, retain their growth and differentiation capacity when applied and immobilized on a substrate using a clinically approved fibrin sealant spray system. PMID:23260090

  8. The Effect of Round Window Sealants on Delayed Hearing Loss in a Guinea Pig Model of Cochlear Implantation.

    PubMed

    Rowe, David; Chambers, Scott; Hampson, Amy; Eastwood, Hayden; O'Leary, Stephen

    2016-09-01

    To determine whether the type of material used to seal the cochlea after round window cochlear implantation influences delayed hearing loss. Cochlear implants are now prescribed to patients with residual, low-frequency hearing. This hearing-which provides perceptual benefits for the implanted ear-is frequently lost for unknown reasons weeks to months after surgery in a proportion of patients. A post-surgical change in cochlear mechanics, related to the material used to seal the cochlea after round window implantation, may contribute to this loss. An electrode array was implanted in guinea pigs via the round window, which was then sealed with muscle, periosteum, or fibrin glue. Auditory brainstem responses (ABRs) to pure tones (2, 8, 16, 24, and 32 kHz) were recorded before surgery and 1, 4, and 12 weeks after surgery, with subjects then euthanized and their cochleae harvested for histological analysis. Muscle and periosteum, but not fibrin glue, exhibited delayed threshold rises at 2 kHz. Twelve weeks after implantation, 2 kHz threshold shifts differed significantly between muscle (mean, 27.1 dB) and fibrin glue (9.3 dB), but not between these groups and periosteum (19.3 dB). Muscle was sometimes associated with much greater tissue reactions than the other sealants. Most cochleae had injuries to the basilar membrane and/or osseous spiral lamina, regardless of sealant. Hair cell counts did not differ significantly among sealants. Delayed, low-frequency hearing loss was observed when cochleae were sealed with muscle or periosteum, but not when cochleae were sealed with fibrin glue.

  9. Platelet interaction with polymerizing fibrin.

    PubMed

    Niewiarowski, S; Regoeczi, E; Stewart, G J; Senyl, A F; Mustard, J F

    1972-03-01

    Interaction of washed pig, rabbit, or human platelets with fibrinogen was studied during its transition to fibrin using photometric, isotopic, and electron microscopic techniques. Untreated fibrinogen and fully polymerized fibrin had no detectable effect on platelets. Fibrinogen, incubated with low concentrations of reptilase or thrombin, formed intermediate products which readily became associated with platelets and caused their aggregation. Neutralization of the thrombin did not prevent this interaction. In the absence of fibrinogen, reptilase did not affect platelets. The interaction of polymerizing fibrin with platelets was accompanied by small losses of platelet constituents (serotonin, adenine nucleotides, platelet factor 4, and lactic dehydrogenase). This loss did not appear to be the result of the platelet release reaction. Inhibitors of the release reaction or of adenosine diphosphate (ADP)-induced aggregation did not prevent the interaction of platelets with polymerizing fibrin. Apyrase or prostaglandin E(1) (PGE(1)) reduced the extent of platelet aggregation by polymerizing fibrin, but the amount of protein associated with platelets was slightly increased. The interaction of polymerizing fibrin with platelets was completely inhibited by ethylenediaminetetraacetate (EDTA) or ethylene glycol bis (beta-aminoethyl ether) N, N,N',N'-tetraacetic acid (EGTA).Fibers formed in solutions of polymerizing fibrin were larger in the presence than in the absence of washed platelets, suggesting that platelets affect fibrin polymerization. The adherence of platelets to polymerizing fibrin may be responsible for the establishment of links between platelets and fibrin in hemostatic plugs and thrombi.

  10. Use of fibrin glue in preventing pseudorecurrence after laparoscopic total extraperitoneal repair of large indirect inguinal hernia

    PubMed Central

    Sürgit, Önder; Çavuşoğlu, Nadir Turgut; Ünal, Yılmaz; Koşar, Pınar Nergis; İçen, Duygu

    2016-01-01

    Purpose Seroma is among the most common complications of laparoscopic total extraperitoneal (TEP) for especially large indirect inguinal hernia, and may be regarded as a recurrence by some patients. A potential area localized behind the mesh and extending from the inguinal cord into the scrotum may be one of the major etiological factors of this complication. Our aim is to describe a novel technique in preventing pseudorecurrence by using fibrin sealant to close that potential dead space. Methods Forty male patients who underwent laparoscopic TEP for indirect inguinal hernia with at least 100-mL volume were included in this prospective clinical study. While fibrin sealant was used to close the potential dead space in the study group, nothing was used in the control group. The volume of postoperative fluid collection on ultrasound was compared between the groups. Results Patient characteristics and the volumes of hernia sac were similar between the 2 groups. The mean volume of postoperative fluid collection was found as 120.2 mL in the control group and 53.7 mL in the study group, indicating a statistical significance (P < 0.001). Conclusion Minimizing the potential dead space with a fibrin sealant can reduce the amount of postoperative fluid collection, namely the incidence of pseudorecurrence. PMID:27617253

  11. Dental sealants guidelines development: 2002-2014.

    PubMed

    Crall, James J; Donly, Kevin J

    2015-01-01

    The purpose of this paper was to review the chronology of dental sealant guideline developments and changes in recommendations regarding sealant usage by various state, national, and international organizations between 2002 and 2014. More specific objectives include: (1) review and summarize the findings of systematic evidence-based reviews and recommendations regarding the use of pit and fissure sealants published since the 2002 American Academy of Pediatric Dentistry Pediatric Restorative Dentistry Consensus Conference; (2) identify consistencies and changes in conclusions or recommendations regarding the use of pit and fissure sealants, and differences in the methods used to develop recommendations/guidelines over time; and (3) describe the purpose and scope of current efforts to update American Dental Association 2008 Evidence-based Clinical Recommendations for the Use of Pit and Fissure Sealants. A summary of recommendations based on experts' synthesis of published evidence and recommendations is included.

  12. Successful application of keratinocyte suspension using autologous fibrin spray.

    PubMed

    Johnstone, Philippa; Kwei, Johnny Sheng-Sun; Filobbos, George; Lewis, Darren; Jeffery, Steven

    2017-05-01

    The back is a challenging anatomical area to resurface in acute burns due to its large surface area, its dependent position with the patient lying down and the shearing forces applied to any method of resurfacing employed. This case study presents the use of Vivostat(®) (Vivostat A/S, Lillerød, Denmark) in resurfacing the back in conjunction with Recell(®) regenerative epithelial suspension. Vivostat(®) (Vivostat A/S, Lillerød, Denmark) is a "novel patented biotechnological process that enables reproducible preparation of autologous fibrin sealant or platelet rich fibrin without cryoprecipitation or a separate thrombin component" [1]. A 29-year-old female sustained 27% total body surface area (TBSA) flame burns, including the whole back. This area was initially grafted with the sandwich autograft/allograft technique on day four after injury, with approximately 80% graft take on day eight. Unfortunately, there was subsequent significant graft loss on the back proving to be a stubborn area to treat despite further grafting sessions. This challenge led to the decision to use Vivostat(®) (Vivostat A/S, Lillerød, Denmark) and Recell(®) to resurface the back. The patient underwent one session of resurfacing with Vivostat(®) (Vivostat A/S, Lillerød, Denmark) and Recell(®) and went on to have full healing on the back. NICE (The National Institute for Health and Care Excellence) states that Recell(®) shows potential to improve healing in acute burns and we believe that its co-delivery with fibrin via Vivostat(®) (Vivostat A/S, Lillerød, Denmark) allows for precise delivery of the fibrin suspended cells while minimising loss in the "run off" encountered when Recell(®) is just simply sprayed on, assisting the anchoring of keratinocytes to the wound surface and thus aiding in the treatment of challenging areas. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  13. High performance channel injection sealant invention abstract

    NASA Technical Reports Server (NTRS)

    Rosser, R. W.; Basiulis, D. I.; Salisbury, D. P. (Inventor)

    1982-01-01

    High performance channel sealant is based on NASA patented cyano and diamidoximine-terminated perfluoroalkylene ether prepolymers that are thermally condensed and cross linked. The sealant contains asbestos and, in its preferred embodiments, Lithofrax, to lower its thermal expansion coefficient and a phenolic metal deactivator. Extensive evaluation shows the sealant is extremely resistant to thermal degradation with an onset point of 280 C. The materials have a volatile content of 0.18%, excellent flexibility, and adherence properties, and fuel resistance. No corrosibility to aluminum or titanium was observed.

  14. Sealant research for solid oxide fuel cells

    SciTech Connect

    Myles, K.M.; Bloom, I.; Krumpelt, M.; Ley, K.L.; Dorris, S.E.; Wagh, A.S.

    1993-11-01

    A suitable sealant must form strong, dense bonds with SOFC components, be compatible, be stable at 1000{degrees}C in SOFC operating environment (H{sub 2} and H{sub 2}O on anode side, O{sub 2} on cathode side), and be electrically insulating. Two types of sealants are being developed: Rigid (Mg ammonium phosphate cement) for the cell edge, and compliant (borate-based glass-ceramic) for stack-to-manifold joining. Testing of both is reported. Shrinkage of the rigid sealant needs to be reduced. Further testing is underway.

  15. GENIPIN-CROSSLINKED FIBRIN HYDROGELS AS A POTENTIAL ADHESIVE TO AUGMENT INTERVERTEBRAL DISC ANNULUS REPAIR

    PubMed Central

    Schek, R.M.; Michalek, A.J.; Iatridis, J.C.

    2011-01-01

    Treatment of damaged intervertebral discs is a significant clinical problem and, despite advances in the repair and replacement of the nucleus pulposus, there are few effective strategies to restore defects in the annulus fibrosus. An annular repair material should meet three specifications: have a modulus similar to the native annulus tissue, support the growth of disc cells, and maintain adhesion to tissue under physiological strain levels. We hypothesized that a genipin crosslinked fibrin gel could meet these requirements. Our mechanical results showed that genipin crosslinked fibrin gels could be created with a modulus in the range of native annular tissue. We also demonstrated that this material is compatible with the in vitro growth of human disc cells, when genipin:fibrin ratios were 0.25:1 or less, although cell proliferation was slower and cell morphology more rounded than for fibrin alone. Finally, lap tests were performed to evaluate adhesion between fibrin gels and pieces of annular tissue. Specimens created without genipin had poor handling properties and readily delaminated, while genipin crosslinked fibrin gels remained adhered to the tissue pieces at strains exceeding physiological levels and failed at 15–30%. This study demonstrated that genipin crosslinked fibrin gels show promise as a gap-filling adhesive biomaterial with tunable material properties, yet the slow cell proliferation suggests this biomaterial may be best suited as a sealant for small annulus fibrosus defects or as an adhesive to augment large annulus repairs. Future studies will evaluate degradation rate, fatigue behaviors, and long-term biocompatibility. PMID:21503869

  16. Staining potential of sealants in/on exterior wall substrates

    SciTech Connect

    Chin, I.R.; Gorrell, T.A.; Scheffler, M.J.

    1996-12-31

    The investigation of dozens of exterior walls on buildings by the authors have revealed that certain sealants used to seal joints in exterior walls have caused the following conditions: 1. Local staining and discoloration of masonry wall substrates due to penetration of sealant into substrates. 2. Local change in absorption of masonry wall substrates due to penetration of sealant into the substrates which results in local discoloration of wall substrates after rains. 3. Surface discoloration of sealant due to dirt accumulation on sealant. 4. Stains in the form of streaks of direct on masonry and on metal wall substrates due to transfer by rain water of some of the dirt on the sealant surface onto the adjacent surface of the substrate. Laboratory and field testing of the major commercially available sealants by the authors to date have revealed that silicone sealants have the propensity to stain certain exterior wall substrates while polyurethane sealants do not; that silicone sealants in service discolor more significantly and faster due to dirt accumulation than polyurethane sealants; that sealant that has penetrated into masonry substrates cannot be entirely removed from the substrate by cleaning; and that preconstruction testing of sealants and proper material selection can help to avoid staining of sealant.

  17. Delayed cerebrospinal fluid leak after watertight dural closure with a polyethylene glycol hydrogel dural sealant in posterior fossa surgery: case report.

    PubMed

    Jito, Junya; Nitta, Naoki; Nozaki, Kazuhiko

    2014-01-01

    A polyethylene glycol (PEG) hydrogel sealant recently has been approved as an adjunct to sutured dural closure in Japan. We treated consecutive six patients with PEG hydrogel sealant in posterior fossa operation. Three of six cases suffered delayed cerebrospinal fluid (CSF) leak after watertight dural closure with the PEG hydrogel sealant, although there was no leak case which was treated with fibrin glue, before 2 years until the adoption of the new material. These patients underwent posterior fossa craniotomy and discharged without remarkable CSF leak. The pseudomeningocele under the occipital wound caused the CSF leak occurr from 5th to 7th week postoperatively. All CSF leak cases needed surgical repair. At the repair, the PEG hydrogel was liquefied and almost absorbed. A fistula on the closure line and a dead space after the absorption of the PEG hydrogel was observed. When the absorbable PEG hydrogel sealant plugs in small gaps of sutured dura, its properties to prevent adhesion might suppress healing process of dural closure, so that CSF could leak through the gaps and collect as a pseudomeningocele in the dead space after absorption of the PEG hydrogel. In posterior fossa surgery a PEG hydrogel sealant should be applied when dural edges are closed tightly without any gaps.

  18. Effects of sealant, viscosity, and bonding agents on microleakage of fissure sealants: An in vitro study

    PubMed Central

    Mehrabkhani, Maryam; Mazhari, Fatemeh; Sadeghi, Samaneh; Ebrahimi, Masoumeh

    2015-01-01

    Objective: The aim of this study was to evaluate the effects of enamel or dentin bonding agent (DBA) and sealant viscosity on sealant microleakage. Materials and Methods: Sixty extracted human premolars were randomly divided into two equal groups (based on sealant viscosity) and each group was divided into three subgroups of 10 teeth. Group 1 (low viscosity sealant, Seal-Rite, Pulpdent, USA with 7.7% filler): Prophylaxis, enameloplasty, etching of occlusal surfaces with 38% of phosphoric acid gel, rinsing and drying, followed by (1) enamel bonding agent (EBA) (Margin Bond, Coltène/Whaledent AG) or (2) DBA (Excite, Ivoclar Vivadent AG, Liechtenstein) or (3) no bonding (NB) prior to sealant application. In Group 2, similar procedures were performed except for applying a high viscosity sealant (Seal-Rite, Pulpdent, The USA with 34.4% filler). Specimens were thermocycled and then immersed in a 0.5% basic fuchsine solution for 24 h next, buccolingual slices of samples were scored under a stereomicroscope. The Kruskal–Wallis and Mann–Whitney U-tests were used for data analysis. Results: There was no significant difference between DBA, EBA, and NB subgroups in the microleakage scores in both groups. Low viscosity sealant had a lower microleakage than the high viscosity sealant in both DBA (P = 0.002) and NB (P = 0.041) subgroups. Conclusion: The results indicated that the use of low viscosity sealant reduced the microleakage of pit and fissure sealants. However, the use of a bonding agent before sealant placement didn’t affect the microleakage. PMID:26929696

  19. Patch tests.

    PubMed

    Lazzarini, Rosana; Duarte, Ida; Ferreira, Alessandra Lindmayer

    2013-01-01

    Patch tests were introduced as a diagnostic tool in the late nineteenth century. Since then, they have improved considerably becoming what they are today. Patch tests are used in the diagnostic investigation of contact dermatitis worldwide. Batteries or series previously studied and standardized should be used in patch testing. The methodology is simple, but it requires adequate training for the results to be correctly interpreted and used. Despite having been used for over a century, it needs improvement like all other diagnostic techniques in the medical field.

  20. Patch tests*

    PubMed Central

    Lazzarini, Rosana; Duarte, Ida; Ferreira, Alessandra Lindmayer

    2013-01-01

    Patch tests were introduced as a diagnostic tool in the late nineteenth century. Since then, they have improved considerably becoming what they are today. Patch tests are used in the diagnostic investigation of contact dermatitis worldwide. Batteries or series previously studied and standardized should be used in patch testing. The methodology is simple, but it requires adequate training for the results to be correctly interpreted and used. Despite having been used for over a century, it needs improvement like all other diagnostic techniques in the medical field. PMID:24474094

  1. Usefulness of a new gelatin glue sealant system for dural closure in a rat durotomy model.

    PubMed

    Kawai, Hisashi; Nakagawa, Ichiro; Nishimura, Fumihiko; Motoyama, Yasushi; Park, Young-Su; Nakamura, Mitsutoshi; Nakase, Hiroyuki; Suzuki, Shuko; Ikada, Yoshito

    2014-01-01

    Watertight dural closure is imperative after neurosurgical procedures, because inadequately treated leakage of cerebrospinal fluid (CSF) can have serious consequences. We used a rat durotomy model to test the usefulness of a new gelatin glue as a dural sealant in a rat model of transdural CSF leakage. All rats were randomly divided into one of the following three treatment groups: no application (control group: N = 18), application of fibrin glue (fibrin glue group: N = 18), and application of the new gelatin glue (new gelatin glue group: N = 18). The craniotomy side was re-opened, and CSF leakage was checked and recorded at 1, 7, and 28 days postoperatively. The new gelatin glue was adequate for stopping CSF leakage; no leakage was observed at postoperative days 1 or 7, and leakage was observed in only one rat at postoperative day 28. This result was statistically significant when compared to the control group (P = 0.002, P = 0.015, P = 0.015, respectively). The pathologic score of the new gelatin group was not different from that of the control or fibrin glue groups. We conclude that our new gelatin glue provides effective watertight closure 1, 7, and 28 days after operation in the rat durotomy model.

  2. The state-of-the-art of ART sealants.

    PubMed

    Frencken, Jo E

    2014-03-01

    Sealing caries-prone pits and fissure systems is an effective caries-preventive measure. There are basically two types of sealant materials: glass-ionomer and resin-based materials. Low- and medium-viscosity glass-ionomers were initially used and showed a low level of retention. With the advent of the ART approach in the mid-nineties, high-viscosity glass-ionomers were introduced as sealant material and the retention rate of ART sealants increased substantially. As the effectiveness of a sealant is measured by its capacity to prevent (dentine) carious lesion development, sealant retention is considered a surrogate endpoint. The ART sealant protocol is described. Systematic reviews and meta-analysis covering low- medium- and high-viscosity glass-ionomer (ART) sealants have concluded that there is no evidence that either glass-ionomer or resin-based sealants prevent dentine carious lesions better. The annual dentine carious lesion development in teeth with high-viscosity glass-ionomer ART sealants over the first three years is 1%. These ART sealants have a high capacity of preventing carious lesion development. Because no electricity and running water is required, ART sealants can be placed both inside and outside the dental surgery. High-viscosity glass-ionomer ART sealants can be used alongside resin-based sealants.41:119-124

  3. [Caries prevention effect of resin based sealants and glass ionomor sealants].

    PubMed

    Liu, Yijie; Rong, Wensheng; Zhao, Xiulan; Wang, Meng; Jiang, Quanchun; Wang, Weijian

    2014-04-01

    To evaluate the effectiveness of resin-based sealants and glass ionomer sealants on caries prevention in the first permanent molars. A randomized controlled, examiner-blinded, 2-year clinical trial with parallel groups was conducted. A total of 419 children (664 first molars) who had at least one sound first permanent molar with deep fissures or fissures with signs of non-cavitated lesions were recruited. They were randomly allocated into three groups.Helioseal F, a light-cured resin-based sealants was used in group R (136 children with 219 first molars). FUJI VII, a light-cured glass ionomer sealants was used in group G (130 children with 218 first molars) and group N (153 children with 227 first molars) was blank control.Follow-up examinations were conducted at 6, 12, and 24 month after sealing to examine the sealants retention and caries incidence. Chi-square test was used to compare the differences of caries incidence among the 3 groups.Generalized estimating equations (GEE) was used to analyze the effective factors of caries incidence. During the 2-year follow-up period, 3.0% (6/197) of the teeth in group R, 6.7% (13/193) of the teeth in group G, and 14.7% (29/197) of the teeth in group N were diagnosed as having developed a cavitated lesion. The difference in the incidence of caries among the three groups was significant(P < 0.05). No significant difference in caries incidence was found between group R and group G (P > 0.05). The tooth-level preventive fractions were 79.6% for resin-based sealants and 54.4% for glass ionomer sealants, respectively. Both resin-based sealants and glass ionomer sealants can effectively prevent the incidence of caries in the first permanent molars. The two sealants have similar caries prevention effect.

  4. Fibrin as a delivery system in wound healing tissue engineering applications.

    PubMed

    Whelan, D; Caplice, N M; Clover, A J P

    2014-12-28

    Fibrin is formed in the body upon initiation of the clotting cascade and is produced commercially for use as a tissue sealant and hemostasis device during surgical procedures. Experimentally fibrin is being increasingly used as a vector to deliver growth factors, cells, drugs and genes in tissue engineering applications mimicking aspects of the extra cellular matrix. Growth factors (GFs) are central to wound healing, inducing cell proliferation, migration and differentiation. Attempts have been made to augment wound healing with GFs, however widespread clinical use has been hindered in vivo due to their rapid metabolism within the body. Fibrin hydrogels protect GFs from rapid degradation and the composition of which can be altered to achieve their optimal release. This article reviews the use of fibrin for the delivery of GFs and details the various strategies that have evolved to alter the release rate so as to enhance the regenerative process, including bi-domain peptides, plasmin degradation sequences and heparin incorporation. This paper also reviews other recent advances in this field, such as dual delivery of cells and GF or sequential release of multiple GF. Copyright © 2014. Published by Elsevier B.V.

  5. Strong evidence for the effectiveness of resin based sealants.

    PubMed

    Deery, Chris

    2013-09-01

    Cochrane Oral Health Group's Trials Register, CENTRAL, Medline via OVID, EMBASE via OVID; SCISEARCH, CAplus, INSPEC, NTIS and PASCAL via STN Easy and DARE, NHS EED, HTA (all to September/ November 2012) and ClinicalTrials.gov (to July 2012). There were no restrictions on language or date of publication. Randomised and quasi-randomised controlled trials of at least 12 months duration comparing no sealant with sealant, or different types of sealants, for preventing caries of occlusal or approximal surfaces of premolar or molar teeth in children and adolescents under 20 years of age. Screening of search results, data extraction and assessment of trial quality (using GRADE methods) were by two reviewers independently. There were 34 trials of children aged five to 16 years, with 12 trials (2575 participants) comparing sealants with no sealant, 21 trials (3202 participants) comparing one sealant with another and one trial (752 participants) comparing two types of sealant with no sealant.Resin sealants compared with no sealants prevented caries in the first permanent molars of children five to 10 years old (six trials at low risk of bias with two years follow up), (odds ratio (OR) 0.12, 95% confidence interval (CI) 0.07 to 0.19). At 48 to 54 months follow-up, the caries preventive effect was maintained (OR 0.21, 95% CI 0.16 to 0.28) although there were only four trials (two were at low and two at high risk of bias).No conclusions could be drawn as to whether glass ionomer sealants compared with no sealants prevented caries at 2 year follow-up. The mean difference in DFS was -0.18, 95% CI -0.39 to 0.03.The relative effectiveness of one type of sealant compared to a different type of sealant was inconclusive as there was great variation in comparisons, outcomes, times of outcomes and background fluoride levels in the 21 studies. There was insufficient evidence for the relative superiority of glass ionomer and resin sealants (very low event rate in many of the 15 trials

  6. A comparative study of fluoride release from two different sealants.

    PubMed

    Ananda, Shimoga-Raju; Mythri, Halappa

    2014-12-01

    The introduction of fluoride releasing sealants and glass ionomer cements as fissure sealants adds another dimension to prevention of pit and fissure caries. The ability of resin sealants and glass ionomer cements to release fluoride on a long term basis to the sealed enamel and the adjacent unsealed pit and fissure and cuspal incline enamel may allow for further reduction in pit and fissure caries experience for children. Hence, the study was conducted to compare the amount of fluoride release in the plaque after placing fluoride releasing pit and fissure sealants and glass ionomer fissure sealants used in Atraumatic Restorative Treatment (ART) approach. To compare the fluoride release of both the materials at the different time intervals. A total of 60 school going children were included in this study. Before application of the sealants, baseline plaque fluoride levels were estimated from all the study subjects. After application of sealants again the same was estimated at an interval of 24 hour, 9 days, 2 weeks and 4 weeks. The peak plaque fluoride levels were achieved at 24 hours after application of fissure sealants in all the groups. Within the limitation of the study, the present study indicated that fluoride releasing fissure sealants may act as a source of fluoride in plaque which will help in preventing pit and fissure and smooth surface caries in the tooth sealed with fissure sealants. Key words:Plaque fluoride, pit and fissures sealants, dental caries.

  7. A comparative study of fluoride release from two different sealants

    PubMed Central

    Ananda, Shimoga-Raju

    2014-01-01

    Objectives: The introduction of fluoride releasing sealants and glass ionomer cements as fissure sealants adds another dimension to prevention of pit and fissure caries. The ability of resin sealants and glass ionomer cements to release fluoride on a long term basis to the sealed enamel and the adjacent unsealed pit and fissure and cuspal incline enamel may allow for further reduction in pit and fissure caries experience for children. Hence, the study was conducted to compare the amount of fluoride release in the plaque after placing fluoride releasing pit and fissure sealants and glass ionomer fissure sealants used in Atraumatic Restorative Treatment (ART) approach. To compare the fluoride release of both the materials at the different time intervals. Material and Methods: A total of 60 school going children were included in this study. Before application of the sealants, baseline plaque fluoride levels were estimated from all the study subjects. After application of sealants again the same was estimated at an interval of 24 hour, 9 days, 2 weeks and 4 weeks. Results: The peak plaque fluoride levels were achieved at 24 hours after application of fissure sealants in all the groups. Conclusions: Within the limitation of the study, the present study indicated that fluoride releasing fissure sealants may act as a source of fluoride in plaque which will help in preventing pit and fissure and smooth surface caries in the tooth sealed with fissure sealants. Key words:Plaque fluoride, pit and fissures sealants, dental caries. PMID:25674315

  8. Laboratory testing of sealants with a marble substrate

    SciTech Connect

    Farmer, M.C.; Cechner, R.A.

    1996-12-31

    Polyurethane and silicone sealants are widely specified for installations with porous substrates such as some stones. However, when a sealant is used against such surfaces, there is a potential for a lack of adequate adhesion, or staining of the tone by misapplication or migration of the liquid components of the sealant system, such as primers or plasticizers in the formulation. Some varieties of marble in particular have been reported to be susceptible to staining and discoloration over time from sealants. Application of new sealant over existing sealants is also of great concern for remedial applications. Determining the level of substrate preparation necessary to achieve adequate bond is critical to the success of the remedial construction project. This paper discusses the development and results of a test program conducted to determine the relative performance of sealants installed on a white marble substrate. The tests performed included wet adhesion tests, accelerated weathering studies, and staining due to plasticizer migration.

  9. Efficacy of fibrinogen/thrombin-coated equine collagen patch in controlling lymphatic leaks.

    PubMed

    Vida, Vladimiro L; Padalino, Massimo A; Barzon, Elisa; Stellin, Giovanni

    2012-07-01

    We report the use of fibrinogen/thrombin-coated equine collagen patch (Tachosil(®) ) as a sealant agent in six patients who underwent heart surgery for congenital heart disease (CHD) and developed an intraoperative lymphatic leakage detected at the time of surgery. The use of fibrinogen/thrombin-coated equine collagen patch proved to be safe and effective in preventing the development of postoperative chylothorax.

  10. Retention and effectiveness of fissure sealants in Kuwaiti school children.

    PubMed

    Francis, R; Mascarenhas, A K; Soparkar, P; Al-Mutawaa, S

    2008-12-01

    To evaluate the retention and effectiveness of fissure sealants in permanent first molars in a public programme. Sealant retention in permanent first molars was evaluated in 452 children aged 6-8 years in 20 primary schools under the care of the School Oral Health Programme, Kuwait-Forsyth. The sealants were placed using rubber dam or cotton roll isolation, after cleaning with pumice and rubber cup, and 15 seconds etching. Sealant retention was evaluated at one and two years and scored as complete, partial or complete loss of sealant. Caries was scored when sealant was partially or completely lost. A total of 2,744 sealants were applied, with 2,324 and 2,288 sealants examined at the end of the first and second year respectively. In two years, 75% of the sealants were completely retained, 2.9% partially lost, 7.3% completely lost, and 14.8% resealed or restored. A small proportion of teeth (0.9%) were carious. Multivariate analyses showed that occlusal surfaces were 2.8 times more likely to retain a sealant than the buccal and palatal pits (95% CI 2.7-3.9, p<0.0001), and maxillary teeth were 1.3 times more likely to retain their sealant than the mandibular teeth (95% CI 1.01-1.5, p=0.04). Maxillary teeth were less likely to be carious (OR=0.6, 95% CI 0.4-0.97), p=0.03) and occlusal surfaces were 2.8 times more likely to be carious (95% CI 1.9-4.3), p<0.0001). No differences in sealant retention (p=0.24) and caries (p=0.19) were seen between teeth isolated using rubberdam or cotton roll. Sealant retention was high, and sealants were effective in preventing caries.

  11. Economic evaluation of dental sealants: A systematic literature review.

    PubMed

    Akinlotan, Marvellous; Chen, Bradley; Fontanilla, Tiana M; Chen, Annie; Fan, Victoria Y

    2017-09-06

    To systematically review the literature on economic evaluations of dental sealants and examine the costs and effectiveness of caries prevention using sealants. Of 21 full-text articles examined, a total of 13 were included in this study. These studies are grouped by the type of intervention as follows: (i) sealants compared with no sealants; (ii) sealants compared with other forms of caries prevention; (iii) resin-based sealants compared with glass-ionomer sealants; (iv) different sealing strategies in primary teeth; (v) different sealing strategies in permanent teeth; and (vi) sealants based on school- or clinic-based setting of delivery. All currency is reported in constant 2010 US$. Cost-effectiveness analyses differed due to varying study designs, assumptions, sealant delivery settings, outcomes, caries risk assessment and study durations. Findings varied on the cost-effectiveness of sealants compared with other caries-preventive strategies. Under the assumption of equal caries risk, always sealing primary molars appeared to be the most effective strategy, whereas risk-based sealing was the optimal strategy with differing caries risk. Studies that assessed sealing strategies in permanent teeth reported that risk-based sealing was more cost-effective than not sealing, but they differed on the cost-effectiveness of risk-based seal compared with non-risk-based seal. Sealants delivered in school settings had mixed results on costs but were as equally effective as sealants delivered in private practices. The cost-effectiveness of sealants is dependent on the conditions of delivery. The list of cost-effectiveness ratios for each intervention can support policy makers to estimate expected returns on their investments in dental sealants. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Injectible candidate sealants for fetal membrane repair: Bonding and toxicity in vitro

    PubMed Central

    Bilic, Grozdana; Brubaker, Carrie; Messersmith, Phillip B.; Mallik, Ajit S.; Quinn, Thomas M.; Haller, Claudia; Done, Elisa; Gucciardo, Leonardo; Zeisberger, Steffen M.; Zimmermann, Roland; Deprest, Jan; Zisch, Andreas H.

    2010-01-01

    Objective This study was undertaken to test injectible surgical sealants that are biocompatible with fetal membranes, eventually for closure of iatrogenic membrane defects. Study Design Dermabond, Histoacryl, Tissucol fibrin glue, and three types of in situ forming poly(ethylene glycol)-based polymer hydrogels were tested for acute toxicity upon direct contact with fetal membranes for 24h. For determination of elution toxicity, extracts of sealants were incubated on amnion cell cultures for 72h. Bonding and toxicity was assessed through morphological and/or biochemical analysis. Results Extracts of all adhesives were non-toxic for cultured cells. However, only Tissucol and one type of poly(ethylene glycol)-based hydrogel, mussel-mimetic tissue adhesive, showed efficient, non-disruptive, non-toxic bonding to fetal membranes. Mussel-mimetic tissue adhesive applied over membrane defects created with a 3.5 mm trocar accomplished leak-proof closure that withstood membrane stretch in an in vitro model. Conclusion A synthetic hydrogel-type tissue adhesive emerged as potential sealing modality for iatrogenic membrane defects that merits further evaluation in vivo. PMID:20096254

  13. In vivo evaluation of a new sealant material on a rat lung air leak model.

    PubMed

    Kobayashi, H; Sekine, T; Nakamura, T; Shimizu, Y

    2001-01-01

    The ability of an albumin-based hydrogel sealant (ABHS) to prevent air leakage through the suture line after pulmonary surgery was evaluated by comparison with that of a fibrin glue (FG). As an air-leak model, a rat lung was used in which a standard incision was made and the burst pressure for ABHS and FG was measured. The average burst pressures at time 0 for the FG and ABHS groups were 30.8+/-15.2 and 77.5 +/-19.1 mmHg, respectively. At Day 3, the value of ABHS (76.3 +/- 15.8 mmHg) was still significantly higher (P<0.05) than that of FG (60.0 +/- 21.9 mmHg). At Day 7, no statistical difference was observed between the FG group(71.2 +/- 18.6 mmHg) and the ABHS group(88.8 +/- 11.7 mmHg). Histological examination of the incision at Day 14 revealed that neither sealant was not visible at the incision site, and there was no evidence of adverse tissue reaction. It was concluded that ABHS had good sealing properties and is an alternative to FG for air leakage treatment in pulmonary surgery.

  14. Novel Approach of Treatment of Pilonidal Sinus Disease With Thrombin Gelatin Matrix as a Sealant.

    PubMed

    Elbanna, Hosam G; Emile, Sameh Hany; Youssef, Mohamed; Thabet, Waleed; El-Hamed, Tito M Abd; Ghnnam, Wagih M

    2016-08-01

    Sacrococcygeal pilonidal sinus disease is a condition caused by insertion of fallen hair shafts into the skin. Different types of operations have been described for the management of pilonidal sinus, yet none of them have proven to be superior to the others. Recently, sealants like fibrin glue have been successfully used. This study aimed to assess the efficacy of thrombin gelatin matrix as a new sealant for pilonidal sinus treatment. This was a prospective study conducted from March 2013 to March 2015. The study was conducted in private hospitals in Mansoura City. The study included 36 male patients (72%) and 14 female patients (28%), with a median age of 22 years. Fifty patients with pilonidal sinus were admitted and treated with thrombin gelatin matrix injection. Incidence and time of pilonidal sinus recurrence, postoperative pain and complications, duration of hospital stay, healing status, and time to return to work were recorded. The median duration of symptoms was 13 months, median operative time was 18 minutes, and median hospital stay was 6 hours. All of the procedures were conducted as day-case surgeries. Median follow-up duration was 24 months. Three patients (6%) had a breakdown of the sealant, and the wound was managed with daily dressings. Recurrence at 1 year was observed in 2 patients (4%). A total of 96% of patients were satisfied with the outcome of the procedure, and 92% of patients resumed their daily activities within 3 days. Follow-up for a longer duration is required to ascertain the efficacy of this new technique. The cost of this treatment might be challenging for resource-limited communities. Management of pilonidal sinus using thrombin gelatin matrix, despite being expensive, is an effective, simple treatment that is easy to perform and associated with low recurrence rate, minimal morbidity, and rapid recovery.

  15. Calcium and fibrin gel structure.

    PubMed

    Okada, M; Blombäck, B

    1983-02-01

    Calcium ions (Ca), when present in the gel forming system, were shown to influence liquid permeation of the gels formed, as judged from the Ks-values (permeability coefficients) of the final gels. On increasing Ca concentration, the Ks-values for Fibrin I and Fibrin II gels increase and a maximum is reached at about 10-20 mM for gels formed at ionic strengths between 0.18 and 0.24. For both gels, clotting times (Ct) were shortened on increasing Ca concentration and the shortening was accompanied by increase in Ks. Magnesium also shortened Ct but had no appreciable effect on Ks. The rate of activation of fibrinogen (release of FPA and FPB) was not much affected by Ca, but the activation required for gelation at Ct, decreased with increasing Ca concentration. After the gels were formed, the removal of Ca by EDTA did not change the flow properties. Our results showed that Ca is of importance for formation of the fibrin gel structure, but it may be of minor importance for preservation of the gel structure after its formation. There is a difference between Fibrin I and Fibrin II gels with regard to Ca dependence. The role of calcium in gelation as well as its physiological implications is discussed.

  16. Copolymer sealant compositions and method for making

    NASA Technical Reports Server (NTRS)

    Singh, Navjot (Inventor); Leman, John Thomas (Inventor); Whitney, John M. (Inventor); Krabbenhoft, Herman Otto (Inventor)

    2003-01-01

    Condensation curable poly(fluoroorgano)siloxane-poly(silarylene)siloxane block copolymer compositions having a glass transition temperature not exceeding about -54.degree. C. and excellent solvent resistance have been found useful as sealants. Polyalkoxysilylorgano compounds, such as 1,4-bis[trimethoxysilyl(ethyl)]benzene have been found to be effective as cross-linkers.

  17. Copolymer sealant compositions and method for making

    NASA Technical Reports Server (NTRS)

    Singh, Navjot (Inventor); Leman, John Thomas (Inventor); Whitney, John M. (Inventor); Krabbenhoft, Herman Otto (Inventor)

    2004-01-01

    Condensation curable poly(fluoroorgano)siloxane-poly(silarylene)siloxane block copolymer compositions having a glass transition temperature not exceeding about -54.degree. C. and excellent solvent resistance have been found useful as sealants. Polyalkoxysilylorgano compounds, such as 1,4-bis[trimethoxysilyl(ethyl)]benzene have been found to be effective as cross-linkers.

  18. Copolymer sealant compositions and method for making

    NASA Technical Reports Server (NTRS)

    Singh, Navjot (Inventor); Leman, John Thomas (Inventor); Whitney, John M. (Inventor); Krabbenhoft, Herman Otto (Inventor)

    2002-01-01

    Condensation curable poly(fluoroorgano)siloxane-poly(silarylene)siloxane block copolymer compositions having a glass transition temperature not exceeding about -54.degree. C. and excellent solvent resistance have been found useful as sealants. Polyalkoxysilylorgano compounds, such as 1,4-bis[trimethoxysilyl(ethyl)]benzene have been found to be effective as cross-linkers.

  19. Bisphenol A and Dental Sealants: Olea's Response.

    PubMed Central

    Olea, N

    2000-01-01

    Comments on "Determination of bisphenol A and related aromatic compounds released from Bis-GMA-based composites and sealants by high performance liquid chromatography." by ulgar R, Olea-Serrano MF, Novillo-Fertrell A, Rivas A, Pazos P, Pedraza V, Navajas J-M, Olea N. Environ Health Perspect 108:21-27 (2000). PMID:11133410

  20. Sustained (rh)VEGF(165) release from a sprayed fibrin biomatrix induces angiogenesis, up-regulation of endogenous VEGF-R2, and reduces ischemic flap necrosis.

    PubMed

    Mittermayr, Rainer; Morton, Tatjana; Hofmann, Martina; Helgerson, Sam; van Griensven, Martijn; Redl, Heinz

    2008-01-01

    This study investigated (1) the release of recombinant human vascular endothelial growth factor ([rh]VEGF(165)) from an in vitro fibrin matrix, (2) the effects of (rh)VEGF(165) released from an in vivo fibrin matrix on ischemic flap necrosis in the rat dorsal skin flap model, and (3) the effects of (rh)VEGF(165) released from an in vivo fibrin matrix on VEGF-R2 expression in transgenic VEGF-R2/luc mice. In vitro fibrin matrices were spiked with (rh)VEGF(165) and demonstrated (rh)VEGF(165) release over 88 hours with 66% recovery. Ischemic dorsal flaps were treated with a fibrin sealant (FS), FS spiked with (rh)VEGF(165), or left untreated. Flaps treated with FS spiked with (rh)VEGF(165) showed greater viability than controls as measured by planimetric analysis. Immunohistochemical analyses revealed stronger neovascularization than that exhibited by controls. Transgenic mice implanted with FS spiked with (rh)VEGF(165) had significant increases in VEGF-R2 expression relative to controls at days 5-13 after implantation. Conclusions drawn from this work are that (1) (rh)VEGF(165) is released from an in vitro fibrin matrix at clinically appropriate times, (2) (rh)VEGF(165) increases the viability of tissue flaps in vivo, and (3) (rh)VEGF(165) induces the expression of VEGF-R2 expression. This work demonstrates the clinical ability of sprayed FS to locally deliver growth factors to ischemic tissue of patients.

  1. Pit and fissure sealants or fluoride varnishes?

    PubMed

    Paglia, L

    2016-09-01

    Despite the general advances in dental care, dental caries is still a global health problem affecting many children. Occlusal surfaces of first permanent molars are the most susceptible sites in the developing permanent dentition. Dentists should use sealants or fluoride varnish - as well as other means - to limit the onset of tooth decay. Application of sealants is a recommended procedure to prevent or control caries. Sealing occlusal surfaces of newly erupted permanent molars in children and teenagers delays caries onset up to 48 months compared with unsealed teeth. However longer follow-ups shows a reduction of the preventive effect [Tikhonova et al., 2015]. A review of 2013 pointed out how sealants are effective in high risk children, however information about the benefits of sealing in other conditions is still scant [Ahovuo-Saloranta et al., 2013]. Fluoride varnishes are frequently used to prevent early childhood caries and reduce caries increment in very young children [Weintraub et al., 2006] and in the most vulnerable populations, where the prevalence of caries is higher and specialist visits are occasional [Chu et al., 2010]. Many studies have reported the effectiveness of different types and forms of fluoride agents in preventing dental caries among children and adolescents [Divaris et al., 2013]. A review clarifies that professional application of a 5% sodium fluoride varnish leads to remineralisation of early enamel caries in children. Solutions of 38% silver diamine fluoride are effective in arresting active dentine caries [Gao et al., 2016]. The last systematic review [Ahovuo-Saloranta et al., 2016], comparing pit and fissure sealants with fluoride varnishes explains that the pooled estimate slightly favours resin sealants over fluoride varnishes at two years. At four and nine years, the only comparative study (with high drop-out rates) found more caries on fluoride-varnished occlusal surfaces than on resin-sealed surfaces. There is evidence

  2. Clinical performance of sealants with and without a bonding agent.

    PubMed

    Pinar, Arzu; Sepet, Elif; Aren, Gamze; Bölükbaşi, Nilüfer; Ulukapi, Hasmet; Turan, Nurten

    2005-05-01

    The objective of this study was to assess the effect of a one-bottle bonding agent on sealant success after 3, 6, 12, and 24 months. The sample group consisted of 30 schoolchildren (8 to 10 years of age) who had all their permanent first molars sound and unsealed. Occlusal sealants were placed on first molars according to a split-mouth design. Sealant scoring occurred at 3, 6, 12, and 24 months and was performed by two clinicians blinded to the treatment group. Fisher's exact test was used to analyze the data. The clinically acceptable marginal integrity rates for sealants with a bonding agent after 3, 6, 12, and 24 months were 93%, 93%, 83%, and 79%, respectively. For sealants without a bonding agent, the clinically acceptable marginal integrity rates after 3, 6, 12, and 24 months were 90%, 88%, 81%, and 77%. The rates for no color change in sealants with a bonding agent after 3, 6, 12, and 24 months were 96%, 93%, 81%, and 75%, respectively. For sealants without a bonding agent, the no color change rates after 3, 6, 12, and 24 months were 93%, 93%, 79%, and 72%. After 24 months, 73% of the sample group were available for recall. The retention rates for sealants with and without a bonding agent after 24 months were 79% and 75%, respectively. The results of the statistical analysis showed that there were no differences among the sealants with and without bonding agents evaluated in relation to marginal integrity, marginal discoloration, and anatomic form. The success of a sealant is related to whether the sealant is applied under optimal conditions. The results of this study show that at the 2-year mark, the placement of a bonding agent under sealants did not significantly affect the clinical success of sealants.

  3. Fissure sealants: Knowledge and practice of Yemeni dental practitioners.

    PubMed

    Al-Maweri, Sadeq Ali; Al-Jamaei, Aisha Ahmed; Halboub, Esam Saleh; Al-Soneidar, Walid Ahmed; Tarakji, Bassel; Alsalhani, Anas

    2016-01-01

    This study was conducted to evaluate Yemeni dental practitioners' knowledge and practices concerning fissure sealants. A modified questionnaire consisted of 25-items was distributed to 500 dentists working in Sana'a City. Descriptive statistics and Chi-square/Fisher's exact tests were used for statistical analyses. The response rate was 74%. Most of the respondents were male (61.3%), general practitioners (84.2%), and had <5 years of clinical experience (48.3%). The respondents showed a reasonable level of knowledge about sealants, with the majority (88%) believed that there is strong scientific evidence about fissure sealants effectiveness and around 90% showed a good understanding of sealant placement instructions. On the other hand, respondents showed insufficient knowledge about sealants clinical practice. Although a high proportion of dental practitioners showed adequate knowledge about dental sealant, following guidelines and standardized procedures in clinical practice is lacking. These emphasize the need for regular continuing education courses for dental professional.

  4. Retention of sealants placed by dental technicians without assistance.

    PubMed

    Foreman, F J; Matis, B A

    1991-01-01

    The retention rate of sealants placed by dental auxiliaries has not been studied extensively. This study recorded and compiled the retention rate of sealants placed by Air Force dental technicians over a two-year period. The technicians, who were equivalent to dental assistants, were trained to place the sealants without assistance using the Vac-Ejector (Whaledent International, New York, NY) system for isolation. Five hundred and ninety-nine sealants on 90 patients were evaluated an average of 13.9 months after sealant placement. The overall complete retention rate was 91.0%, with a partial loss rate of 7.0%, and a complete loss rate of 2.0%. These results suggest that pit and fissure sealants can be placed in this cost-effective manner with a relatively high retention rate.

  5. Carrier-bound fibrin sealant compared to oxidized cellulose application after liver resection

    PubMed Central

    Zacharias, Thomas; Ferreira, Nelio

    2012-01-01

    Objective The aim of the study was to compare the incidence of post-operative complications between those patients that received TachoSil® to the transection surface of the liver vs. those that received Surgicel®. Methods Retrospective study of a prospective database in a tertiary hospital. Primary endpoints were overall complications. Secondary endpoints were liver surgery-specific composite endpoint, major complications and hospital stay. Uni- and multivariate analysis of predictive factors for complications and subgroup analysis were performed. Results One hundred thirty-three liver resections were performed between 9 November 2007 and 2 November 2011: 64 with TachoSil® and 69 with Surgicel® application. Both groups were equivalent concerning demographic, clinical and major intra-operative data. No significant differences were observed in overall complication rate (62.5% vs. 62.3%), liver surgery-specific composite endpoint (12.5% vs. 18.8%), major complication rate (18.7% vs. 24.6%) and median hospital stay (13 vs. 10 days) for TachoSil® and Surgicel® application, respectively. Predictive factors for complications in multivariate analysis were: American Society of Anesthesiology Score ≥3 and duration of surgery >240 min. Subgroup analysis found a reduced complication rate with TachoSil® for major hepatectomy. Conclusion The results of the present study suggest that the routine use of TachoSil® after a liver resection does not reduce the overall complication rate compared with Surgicel® application. However, TachoSil® may be beneficial in a major hepatectomy. PMID:23134186

  6. Fibrin Sealant Foam Sprayed Directly on Liver Injuries Decreases Blood Loss in Resuscitated Rats

    DTIC Science & Technology

    2000-08-01

    produced and whether foam in the abdo - men prevents the subsequent operating surgeon from identifying injured structures. Delivery devices and optimal... CT : Greenwood Press; 1992. 7. Bellamy RF. The causes of death in conventional land warfare: implications for combat casualty care research. Mil Med

  7. The Potential Utility of Fibrin Sealant Dressing in Repair of Vascular Injury in Swine

    DTIC Science & Technology

    2007-01-12

    If combined with an elective interventional radiologic pro- cedure (e.g. embolization or stenting ), it may also offer an alternative to suture repair...groups. The dressings were mostly (6-week) or com- pletely (8-week) biodegraded and reabsorbed. The new tissue within the injury site had similar... stent . Other topical hemostatic products are less effective than FSD in these circumstances because they are not likely to hold up against the high

  8. Pit and fissure sealants--an ongoing commitment.

    PubMed

    Ignelzi, Michael A

    2010-10-01

    The purpose of this article is to provide the dental health professional with sound science related to sealants so that he/she can provide the best care to his/her patients. This article will synthesize the recommendations made by the American Academy of Pediatric Dentistry and the American Dental Association, review the rationale as to why sealants should be placed on a routine basis, and provide practical suggestions on how to optimize sealant placement.

  9. Fibrinogen and thrombin concentrations are critical for fibrin glue adherence in rat high-risk colon anastomoses

    PubMed Central

    Buen, Eliseo Portilla-de; Orozco-Mosqueda, Abel; Leal-Cortés, Caridad; Vázquez-Camacho, Gonzalo; Fuentes-Orozco, Clotilde; Alvarez-Villaseñor, Andrea Socorro; Macías-Amezcua, Michel Dassaejv; González-Ojeda, Alejandro

    2014-01-01

    OBJECTIVE: Fibrin glues have not been consistently successful in preventing the dehiscence of high-risk colonic anastomoses. Fibrinogen and thrombin concentrations in glues determine their ability to function as sealants, healers, and/or adhesives. The objective of the current study was to compare the effects of different concentrations of fibrinogen and thrombin on bursting pressure, leaks, dehiscence, and morphology of high-risk ischemic colonic anastomoses using fibrin glue in rats. METHODS: Colonic anastomoses in adult female Sprague-Dawley rats (weight, 250-350 g) treated with fibrin glue containing different concentrations of fibrinogen and thrombin were evaluated at post-operative day 5. The interventions were low-risk (normal) or high-risk (ischemic) end-to-end colonic anastomoses using polypropylene sutures and topical application of fibrinogen at high (120 mg/mL) or low (40 mg/mL) concentrations and thrombin at high (1000 IU/mL) or low (500 IU/mL) concentrations. RESULTS: Ischemia alone, anastomosis alone, or both together reduced the bursting pressure. Glues containing a low fibrinogen concentration improved this parameter in all cases. High thrombin in combination with low fibrinogen also improved adherence exclusively in low-risk anastomoses. No differences were detected with respect to macroscopic parameters, histopathology, or hydroxyproline content at 5 days post-anastomosis. CONCLUSIONS: Fibrin glue with a low fibrinogen content normalizes the bursting pressure of high-risk ischemic left-colon anastomoses in rats at day 5 after surgery. PMID:24714834

  10. Cryogenic adhesives and sealants: Abstracted publications

    NASA Technical Reports Server (NTRS)

    Williamson, F. R.; Olien, N. A.

    1977-01-01

    Abstracts of primary documents containing original experimental data on the properties of adhesives and sealants at cryogenic temperatures are presented. The most important references mentioned in each document are cited. In addition, a brief annotation is given for documents considered secondary in nature, such as republications or variations of original reports, progress reports leading to final reports included as primary documents, and experimental data on adhesive properties at temperatures between about 130 K and room temperature.

  11. Thermally resistant polymers for fuel tank sealants

    NASA Technical Reports Server (NTRS)

    Webster, J. A.

    1973-01-01

    Imide-linked perfluoroalkylene ether polymers, that were developed for the high temperature fuel tank sealant application, are discussed. Modifications of polymer structure and properties were realized through use of a new aromatic dianhydride intermediate containing an ether-linked perfluoroalkylene segment. Tests of thermal, oxidative and hydrolytic stability, fuel resistance, and adhesion are discussed along with tensile strength and elongation results. Efforts to effect a low temperature condensation of amic acid prepolymer to form imide links inside are described.

  12. DEVELOPMENT OF SOLVENT-RESISTANT SEALANTS.

    DTIC Science & Technology

    Urethane type sealants compounded from CF3 and C7F15-containing polyether triols, toluene diisocyanate and moisture cured were developed with good...resistance to paint-stripper solvents, high mechanical properties and excellent adhesion to aluminum substrate. A number of fluorine-containing mono...and diglycidyl ethers, perfluorinated epoxides and fluorine-rich diamines and polyols were synthesized for compounding into urethane- and epoxy-type

  13. Marginal Microleakage of Conventional Fissure Sealants and Self-Adhering Flowable Composite as Fissure Sealant in Permanent Teeth

    PubMed Central

    Rahimian-Imam, Sara; Fayazi, Mohammad Reza

    2015-01-01

    Objectives: Application of sealants is a safe and effective way to prevent occlusal caries in the posterior teeth. A successful sealant therapy depends on good isolation. Decreased steps of adhesive application may enable proper isolation and use of self-adhering flowable composites for sealant therapy. This study sought to compare the marginal microleakage of fissure sealants and self-adhering flowable composites in permanent teeth. Materials and Methods: This in vitro, experimental study was conducted on 60 extracted human premolar teeth. The teeth were divided randomly into two groups of 30. In the first group, fissure sealant (Clinpro, 3M ESPE, USA) was placed on the teeth. In the second group, self-adhering flowable composite (Vertise Flow, Kerr, USA) was applied as the sealant. Then, both groups were immersed in 0.5% fuchsin dye solution for 24 hours. Sectioned samples were observed with a stereomicroscope for the extent of dye penetration. Data were analyzed using SPSS 21 and the Mann-Whitney test (P<0.05). Results: Microleakage in the fissure sealant group was significantly higher than that in the self-adhering flowable composite group (P<0.001). Conclusion: Microleakage was less using self-adhering flowable composite compared to conventional fissure sealant; therefore, self-adhering flowable composite can be used as a suitable fissure sealant in permanent teeth. PMID:26884777

  14. Viscous Glass Sealants for SOFC Applications

    SciTech Connect

    Scott Misture

    2012-09-30

    Two series of silicate glasses that contain gallium as the primary critical component have been identified and optimized for viscous sealing of solid oxide fuel cells operating from 650 to 850°C. Both series of glass sealants crystallize partially upon heat treatment and yield multiphase microstructures that allow viscous flow at temperatures as low as 650°C. A fully amorphous sealant was also developed by isolating, synthesizing and testing a silicate glass of the same composition as the remnant glassy phase in one of the two glass series. Of ~40 glasses tested for longer than 500 hours, a set of 5 glasses has been further tested for up to 1000h in air, wet hydrogen, and against both yttria-stabilized zirconia and aluminized stainless steel. In some cases the testing times reached 2000h. The reactivity testing has provided new insight into the effects of Y, Zr, and Al on bulk and surface crystallization in boro-gallio-silicate glasses, and demonstrated that at least 5 of the newly-developed glasses are viable viscous sealants.

  15. [Alloplastic cancellous bone replacement and fibrin glue in hand surgery].

    PubMed

    Wolter, T P; Fuchs, P; Pallua, N

    2010-10-01

    Alloplastic replacement of cancellous bone is being increasingly used in the clinical setting. The use in hand surgery, however, is only sparsely documented. We report about the use of micro- and macroporous biphasic calicium phosphate granulate (Tricos (®)) in combination with fibrin sealant (Tissucol (®)) in six patients undergoing surgery of the hand involving cancellous bone deficits. The indications ranged from carpal stabilisation to DIP athrodesis. Follow-up time was up to 15 months. Because cancellous bone harvesting could be avoided, morbidity and the extent of surgery could be reduced in all patients. Healing was uneventful and the clinical course as documented by X-ray controls, toleration of physiotherapeutic exercises and stability was analogous to that of conventional surgery involving cancellous bone grafting. These first results indicate that alloplastic replacement of spongiosa grafts, especially by micro- and macroporous biphasic calcium phosphate granulate can possibly be successfully used in surgery of the hand. The extent of bony remodelling still needs to be determined by further examination. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Fluoride release and uptake abilities of different fissure sealants.

    PubMed

    Poggio, Claudio; Andenna, Gianluigi; Ceci, Matteo; Beltrami, Riccardo; Colombo, Marco; Cucca, Lucia

    2016-07-01

    The long-term capability of resin sealants and glass ionomer cements to release fluoride is associated to a reduction in pit and fissure caries. The regular use of fluoride varnishes/toothpastes can result in the absorption of fluoride into the sealant. The objective of the present study was to assess the fluoride release/uptake capacities of different fissure sealants. Three different fissure sealants (Fuji Triage/GC, Fissurit FX/Voco and Grandio Seal/Voco) were examined. Ten discs of each material were prepared. Each disc was incubated with distilled water and then the solution analyzed for diluted for fluoride concentration, using a combination of fluoride electrode (OrionGP 1 S/N 13824, Orion Research Inc, Boston, MA, USA) connected to an expandable ion analyzer (Orion 720A, Orion Research Inc, Boston, MA, USA). Standard curves between 1 and 100 ppm F- were used to calibrate the electrode. Cumulative fluoride release was measured on days 1, 2, 3, 5, 7, 21, 35 and 49, then two different fluoride varnishes/pastes (Profluorid Varnish/Voco, MI Paste Plus/GC), were applied to the sealants tested, and fluoride release (after reuptake) was measured on days 56, 70 and 84. Kruskal Wallis test confirmed significant differences in fluoride release between Fuji Triage/GC and Fissurit FX/Voco and Grandio Seal/Voco from day 1 (P < 0.001). The application of fluoride varnish Profluorid Varnish enhanced the fluoride release for all sealants (P < 0.05). MI Paste Plus enhanced the fluoride release for all sealants except for Fuji Triage/GC (P > 0.05). The GIC-based sealant (Fuji Triage/GC) released significantly more fluoride than the resin sealants tested. The exposure to the fluoridated varnish (Profluorid Varnish) significantly recharged the sealants tested more than the CPP-ACPF toothpaste (MI Paste Plus). Fissure sealants, fluoride release, fluoride uptake, glass ionomer cements.

  17. Acute fibrinous and organising pneumonia.

    PubMed

    Guimarães, Catarina; Sanches, Inês; Ferreira, Catarina

    2012-03-20

    Acute fibrinous and organising pneumonia (AFOP) was recently described as an unusual pattern of diffuse lung disease. Particular characteristics make the differential diagnosis with the well recognised clinical patterns of diffuse alveolar damage, cryptogenic organising pneumonia or eosinophilic pneumonia. The lack of hyaline membranes, the presence of intra-alveolar fibrin, absence of noticeable eosinophils and patchy distribution suggests that AFOP define a distinct histological pattern. The authors describe the case of a woman diagnosed with AFOP after surgical lung biopsy, in association with primary biliary cirrhosis. The patient presented dyspnoea, fatigue, dry cough and thoracic pain. The CT scan showed bilateral patchy infiltrates predominantly in the lower lobes. Flexible bronchoscopy and subsidiary techniques were inconclusive and biopsy through video-assisted thoracoscopic surgery led to anatomopathological diagnosis of AFOP. The patient is having a good clinical response to prednisone.

  18. Acute fibrinous and organising pneumonia

    PubMed Central

    Guimarães, Catarina; Sanches, Inês; Ferreira, Catarina

    2012-01-01

    Acute fibrinous and organising pneumonia (AFOP) was recently described as an unusual pattern of diffuse lung disease. Particular characteristics make the differential diagnosis with the well recognised clinical patterns of diffuse alveolar damage, cryptogenic organising pneumonia or eosinophilic pneumonia. The lack of hyaline membranes, the presence of intra-alveolar fibrin, absence of noticeable eosinophils and patchy distribution suggests that AFOP define a distinct histological pattern. The authors describe the case of a woman diagnosed with AFOP after surgical lung biopsy, in association with primary biliary cirrhosis. The patient presented dyspnoea, fatigue, dry cough and thoracic pain. The CT scan showed bilateral patchy infiltrates predominantly in the lower lobes. Flexible bronchoscopy and subsidiary techniques were inconclusive and biopsy through video-assisted thoracoscopic surgery led to anatomopathological diagnosis of AFOP. The patient is having a good clinical response to prednisone. PMID:22605688

  19. Granisetron Transdermal Patch

    MedlinePlus

    ... patch. Each patch is stuck onto a thin plastic liner and a separate rigid plastic film. Do not open the pouch in advance, ... cut the patch into pieces. Peel the thin plastic liner off of the printed side of the ...

  20. Methylphenidate Transdermal Patch

    MedlinePlus

    ... still remove the patch at your regular patch removal time. Do not apply extra patches to make ... room temperature and away from excess heat and moisture (not in the bathroom). Do not refrigerate or ...

  1. Iodixanol as a Contrast Agent in a Fibrin Hydrogel for Endodontic Applications

    PubMed Central

    Hertig, Gabriel; Zehnder, Matthias; Woloszyk, Anna; Mitsiadis, Thimios A.; Ivica, Anja; Weber, Franz E.

    2017-01-01

    The application of biomaterials used in regenerative endodontics should be traceable. In this study, we checked some basic effects of rendering a fibrin hydrogel radiopaque using an iodine-based contrast agent (iodixanol) approved for systemic application. Fibrin hydrogels were prepared from a fibrin sealant (Tisseel) using either an isotonic iodixanol solution (Visipaque 320, test) or Tris buffer (control) as a diluent. Gelation kinetics, radiopacity, and swelling of lyophilized hydrogels were tested using standard methods. Hydrogel structure was evaluated using scanning electron microscopy (SEM). Furthermore, iodixanol release from the test gels was assessed using spectrophotometry, and tissue compatibility was compared between test and control hydrogels using the chick chorioallantoic membrane (CAM) assay. Results were compared using pairwise t-test, p < 0.05. Iodixanol caused a 70-fold delay in gelation to 26 min in the test compared to the control hydrogels (22 ± 1 s). Radiopacity of the test gels was 1.9 ± 0.2 mm Al/mm, compared to zero in the control hydrogels. Lyophilized hydrogel swelling was strongly reduced when iodixanol was added to the hydrogel (p < 0.05). Test hydrogels had an altered SEM appearance compared to controls, and exhibited a reduced porosity. Iodixanol release from the test hydrogels reached 14.5 ± 0.5% after 120 h and then ceased. This release did not have any apparent toxic effect and neither affected the viability, nor the physiology or vascularization of the CAM of fertilized chicken eggs. Iodixanol can render a fibrin hydrogel radiopaque and maintains its tissue compatibility, yet impacts gelation kinetics and hydrogel porosity. PMID:28360862

  2. Silicone Rubber Superstrate Loaded Patch Antenna Design Using Slotting Technique

    NASA Astrophysics Data System (ADS)

    Kaur, Bhupinder; Saini, Garima; Saini, Ashish

    2016-09-01

    For the protection of antenna from external environmental conditions, there is a need that antenna should be covered with a stable, non-reactive, highly durable and weather resistive material which is insensitive to changing external environment. Hence, in this paper silicone rubber is proposed as a superstrate layer for patch antenna for its protection. The electrical properties of silicon rubber sealant are experimentally found out and its effect of using as superstrate on coaxial fed microstrip patch antenna using transmission line model is observed. The overall performance is degraded by slightly after the use of superstrate. Further to improve the performance of superstrate loaded antenna, patch slots and ground defects have been proposed. The proposed design achieves the wideband of 790 MHz (13.59 %), gain of 7.12 dB, VSWR of 1.12 and efficiency of 83.02 %.

  3. Cabbage Patch

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This Sojourner rover image of the Cabbage Patch shows small rounded objects on the surface that are about 3-4 cm across. Some of these are within excavations, which are about 0.5 cm wide. Several questions arise about the pebbles: Why are they rounded? Where did they come from? What do they mean?

    Geologists use MULTIPLE WORKING HYPOTHESES when attempting to explain observations. Some hypotheses that could account for the pebbles are: They were rounded during transport by waters of catastrophic floods and deposited on the Ares Vallis floodplain They were rounded by wave action on an ancient Martian beach They were rounded during glacial transport They are glasses that were produced by melting during impact cratering. The glass was first ejected from the crater, then molded into spherical shapes or drops as it traveled through the atmosphere, and finally was deposited at the sites They are spatter from lava flows They are nodules brought up from the deep Martian interior by lava flows or pyroclastic eruptions. They are concretions formed in sedimentary rocks They came from ancient conglomerate rocks. The pebbles were rounded by water action and subsequently lithified into conglomerate rocks. Later, the waters of catastrophic floods transported the conglomerates and deposited them on the Ares floodplain. The pebbles were then freed from the rocks by weathering. A combination of the above

    Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  4. Clinical sealant retention following two different tooth-cleaning techniques.

    PubMed

    Gillcrist, J A; Vaughan, M P; Plumlee, G N; Wade, G

    1998-01-01

    This study compared the effectiveness of two different tooth-cleaning techniques on clinical sealant retention. Seventy-four children in second and third grades at an elementary school in the rural town of Waverly, Tennessee, had sealants applied to four, noncarious, fully erupted, first permanent molar teeth. The teeth had been cleaned using a brush attached to a rotary instrument with fluoridated prophy paste, versus a toothbrush without paste (dry brushing). A split-mouth design was used, whereby one side (upper and lower) of the mouth was subject to one tooth-cleaning technique while the opposite side received the other technique. Twelve months after a single application of pit and fissure sealant, 63 children were available for recall. Exactly 252 teeth were examined and overall retention was high, with approximately 98 percent of sealants retained. Although the greatest loss of sealant occurred with the rotary instrument technique, the difference in proportions of missing sealant between techniques was not statistically significant. In this study, the tooth-cleaning technique of dry brushing with a toothbrush as a preparatory step in the sealant procedure yielded high clinical sealant retention at 12 months. This retention was comparable to that observed with rotary instrumentation. This finding suggests that dry brushing by the operator may be an acceptable alternative to using a rotary instrument with brush and paste.

  5. Fibrin glue‐assisted glaucoma drainage device surgery

    PubMed Central

    Kahook, M Y; Noecker, R J

    2006-01-01

    Aim To describe the use of fibrin glue as a suture substitute for portions of glaucoma drainage device (GDD) surgery. Methods Retrospective non‐randomised case–control study reviewing 28 consecutive cases of GDD implantation using traditional suture material compared with 14 consecutive cases of GDD implantation using Tisseel fibrin glue (Baxter AG, Vienna, Austria) for portions of the procedure. The fibrin glue was used to close the conjunctiva, secure the pericardium patch graft and secure the tube to the sclera. Three‐month follow‐up data for each group as well as data on operating times, postoperative conjunctival inflammation, drugs used for glaucoma and intraocular pressure (IOP) were evaluated. Statistical analysis was carried out using analysis of variance. Results The mean (SD) age of the patients in the suture group (17 men and 11 women) was 56.6 (10.5) years and that in the Tisseel‐assisted group (8 men and 6 women) was 54.7 (8.6) years (p = 0.56). No significant differences were observed in IOP levels at any time point between the two groups. No significant differences were found for the need for postoperative glaucoma drops or postoperative complication rates in both groups. Conjunctival inflammation was more pronounced in the suture group (p = 0.002) using a standard scale for comparison. The mean (SD) time of surgery was significantly less for the Tisseel‐assisted group, 15.0 (3.11) min, than for the suture group, 25.93 (4.04) min (p<0.001). Conclusions Tisseel fibrin glue seems to be a safe substitute for some of the sutures used in GDD surgery. Use of Tisseel seems to have no effect on IOP control or complications, whereas it considerably improved postoperative conjunctival inflammation and reduced time of surgery. Further studies are needed to better understand the role of fibrin glue in GDD implantation. PMID:16916877

  6. The Maine Sealant Manual for School-Based and School-Linked Dental Sealant Programs.

    ERIC Educational Resources Information Center

    Hayward, Kneka, Ed.

    This manual is designed for use by school personnel and dental personnel to aid in the development and maintenance of school-based or school-linked dental sealant programs. The sections include (1) "Introduction"; (2) "Guidelines" (school selection, school contacts, dental providers, target grades, and tooth selection…

  7. Sealant materials for solid oxide fuel cells

    SciTech Connect

    Krumpelt, M.

    1995-08-01

    The objective of this work is to complete the development of soft glass-ceramic sealants for the solid oxide fuel cell (SOFC). Among other requirements, the materials must soften at the operation temperature of the fuel cell (600-1000{degrees}C) to relieve stresses between stack components, and their thermal expansions must be tailored to match those of the stack materials. Specific objectives included addressing the needs of industrial fuel cell developers, based on their evaluation of samples we supply, as well as working with commercial glass producers to achieve scaled-up production of the materials without changing their properties.

  8. Viscoseal performance with rarefied-gas sealant

    NASA Technical Reports Server (NTRS)

    Milligan, M. W.

    1973-01-01

    A fundamental study of viscoseals having a rarefied gas as the sealant was conducted. Both experimental and analytical investigations are reported. Three different analytical models were formulated and are described in detail. An experimental investigation was conducted on multiple grooved two-inch diameter viscoseals over a wide range of gas densities and shaft speeds up to 30,000 rpm. Comparisons are presented between actual viscoseal performance and the theoretical predictions for both sealing coefficient and net leakage parameters as functions of the degree of gas rarefication. Recommendations are presented for the use of the analytical models.

  9. Fibrin biomatrix-conjugated platelet-derived growth factor AB accelerates wound healing in severe thermal injury.

    PubMed

    Mittermayr, Rainer; Branski, Ludwik; Moritz, Martina; Jeschke, Marc G; Herndon, David N; Traber, Daniel; Schense, Jason; Gampfer, Jörg; Goppelt, Andreas; Redl, Heinz

    2016-05-01

    Controlled delivery of growth factors from biodegradable biomatrices could accelerate and improve impaired wound healing. The study aim was to determine whether platelet-derived growth factor AB (PDGF.AB) with a transglutaminase (TG) crosslinking substrate site released from a fibrin biomatrix improves wound healing in severe thermal injury. The binding and release kinetics of TG-PDGF.AB were determined in vitro. Third-degree contact burns (dorsum of Yorkshire pigs) underwent epifascial necrosectomy 24 h post-burn. Wound sites were covered with autologous meshed (3:1) split-thickness skin autografts and either secured with staples or attached with sprayed fibrin sealant (FS; n = 8/group). TG-PDGF.AB binds to the fibrin biomatrix using the TG activity of factor XIIIa, and is subsequently released through enzymatic cleavage. Three doses of TG-PDGF.AB in FS (100 ng, 1 µg and 11 µg/ml FS) were tested. TG-PDGF.AB was bound to the fibrin biomatrix as evidenced by western blot analysis and subsequently released by enzymatic cleavage. A significantly accelerated and improved wound healing was achieved using sprayed FS containing TG-PDGF.AB compared to staples alone. Low concentrations (100 ng-1 µg TG-PDGF.AB/ml final FS clot) demonstrated to be sufficient to attain a nearly complete closure of mesh interstices 14 days after grafting. TG-PDGF.AB incorporated in FS via a specific binding technology was shown to be effective in grafted third-degree burn wounds. The adhesive properties of the fibrin matrix in conjunction with the prolonged growth factor stimulus enabled by this binding technology could be favourable in many pathological situations associated with wound-healing disturbances. Copyright © 2013 John Wiley & Sons, Ltd.

  10. Formulation and Characterization of Antibacterial Fluoride-releasing Sealants

    PubMed Central

    Fan, Yuwei; Townsend, Janice; Wang, Yapin; Lee, Eun Chee; Evans, Katie; Hender, Erica; Hagan, Joseph L.; Xu, Xiaoming

    2013-01-01

    Purpose The purpose of this study was to formulate and characterize experimental antibacterial fluoride-releasing sealants and compare them with commercial sealants for fluoride release, recharge, adhesion, and microleakage. Methods Two experimental sealants (Exp-1, Exp-2) containing a synthesized antibacterial fluoride-releasing monomer and fluoride-releasing filler were formulated. Exp-2 also contained NovaMin nanoparticles. Commercial sealants Clinpro (CL) FluoroShield (FS), and SeLECT Defense (E34) were also included. Fluoride release from disk samples in deionized water was measured daily using an ion-selective electrode for 14 days, and after recharging with Neutra-Foam (2.0% sodium fluoride), fluoride was measured for 5 days. Microtensile bonding strengths (MTBS) to enamel were tested after 24-hour storage in water at 37°C or thermocycling 5-55°C for 1,000 cycles. A microleakage test was conducted on extracted teeth using a dye-penetration method. The data were analyzed using analysis of variance with the Tukey’s honestly significant difference test and Kruskal-Wallis test. Results Exp-1 and Exp-2 had significantly higher fluoride release and recharge capabilities than CL and FL (P<.05). All tested sealants had similar MTBS before and after thermocycling. Exp-2 and Exp-1 had significantly lower microleakage scores (P<.05) than other groups. Conclusion The experimental sealants had higher fluoride release and recharge capabilities and similar or better retention than commercial sealants. PMID:23635887

  11. Formulation and characterization of antibacterial fluoride-releasing sealants.

    PubMed

    Fan, Yuwei; Townsend, Janice; Wang, Yapin; Lee, Eun Chee; Evans, Katie; Hender, Erica; Hagan, Joseph L; Xu, Xiaoming

    2013-01-01

    The purpose of this study was to formulate and characterize experimental antibacterial fluoride-releasing sealants and compare them with commercial sealants for fluoride release, recharge, adhesion, and microleakage. Two experimental sealants (Exp-1, Exp-2) containing a synthesized antibacterial fluoride-releasing monomer and fluoride-releasing filler were formulated. Exp-2 also contained NovaMin nanoparticles. Commercial sealants Clinpro (CL) FluroShield (FS), and SeLECT Defense (E34) were also included. Fluoride release from disk samples in deionized water was measured daily using an ion-selective electrode for 14 days, and after recharging with Neutra-Foam (2.0% sodium fluoride), fluoride was measured for 5 days. Microtensile bonding strengths (MTBS) to enamel were tested after 24-hour storage in water at 37°C or thermocycling 5-55°C for 1,000 cycles. A microleakage test was conducted on extracted teeth using a dye-penetration method. The data were analyzed using analysis of variance with the Tukey's honestly significant difference test and Kruskal-Wallis test. Exp-1 and Exp-2 had significantly higher fluoride release and recharge capabilities than CL and FL (P<.05). All tested sealants had similar MTBS before and after thermocycling. Exp-2 and Exp-1 had significantly lower microleakage scores (P<.05) than other groups. The experimental sealants had higher fluoride release and recharge capabilities and similar or better retention than commercial sealants.

  12. Orbiter Reinforced Carbon-Carbon Advanced Sealant Systems: Screening Tests

    NASA Technical Reports Server (NTRS)

    Curry, Donald M.; Lewis, Ronad K.; Norman, Ignacio; Chao, Dennis; Nicholson, Leonard S. (Technical Monitor)

    2000-01-01

    Oxidation protection for the Orbiter reinforced carbon-carbon (RCC consists of three components: silicon carbide coating, tetraethyl orthosilicate (TEOS) impregnated into the carbon substrate and a silicon based surface sealant (designated Type A). The Orbiter Type A sealant is being consumed each mission, which results in increased carbon-carbon substrate mass loss, which adversely impacts the mission life of the RCC components. In addition, the sealant loss in combination with launch pad contamination (salt deposit and zinc oxide) results in RCC pinholes. A sealant refurbishment schedule to maintain mission life and minimize affects of pin hole formation has been implemented in the Orbiter maintenance schedule. The objective of this investigation is to develop an advanced sealant system for the RCC that extends the refurbishment schedule by reducing sealant loss/pin hole formation and that can be applied to existing Orbiter RCC components. This paper presents the results of arc jet screening tests conducted on several sealants that are being considered for application to the Orbiter RCC.

  13. Orbiter Reinforced Carbon-Carbon Advanced Sealant Systems: Screening Tests

    NASA Technical Reports Server (NTRS)

    Curry, Donald M.; Lewis, Ronad K.; Norman, Ignacio; Chao, Dennis; Nicholson, Leonard S. (Technical Monitor)

    2000-01-01

    Oxidation protection for the Orbiter reinforced carbon-carbon (RCC consists of three components: silicon carbide coating, tetraethyl orthosilicate (TEOS) impregnated into the carbon substrate and a silicon based surface sealant (designated Type A). The Orbiter Type A sealant is being consumed each mission, which results in increased carbon-carbon substrate mass loss, which adversely impacts the mission life of the RCC components. In addition, the sealant loss in combination with launch pad contamination (salt deposit and zinc oxide) results in RCC pinholes. A sealant refurbishment schedule to maintain mission life and minimize affects of pin hole formation has been implemented in the Orbiter maintenance schedule. The objective of this investigation is to develop an advanced sealant system for the RCC that extends the refurbishment schedule by reducing sealant loss/pin hole formation and that can be applied to existing Orbiter RCC components. This paper presents the results of arc jet screening tests conducted on several sealants that are being considered for application to the Orbiter RCC.

  14. Sealants for preventing dental decay in the permanent teeth.

    PubMed

    Ahovuo-Saloranta, Anneli; Forss, Helena; Walsh, Tanya; Hiiri, Anne; Nordblad, Anne; Mäkelä, Marjukka; Worthington, Helen V

    2013-03-28

    Dental sealants were introduced in the 1960s to help prevent dental caries in the pits and fissures of mainly the occlusal tooth surfaces. Sealants act to prevent the growth of bacteria that can lead to dental decay. There is evidence to suggest that fissure sealants are effective in preventing caries in children and adolescents when compared to no sealants. Their effectiveness may be related to the caries prevalence in the population. To compare the effects of different types of fissure sealants in preventing caries in permanent teeth in children and adolescents. We searched the Cochrane Oral Health Group's Trials Register (to 1 November 2012); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 7); MEDLINE via OVID (1946 to 1 November 2012); EMBASE via OVID (1980 to 1 November 2012); SCISEARCH, CAplus, INSPEC, NTIS and PASCAL via STN Easy (to 1 September 2012); and DARE, NHS EED and HTA (via the CAIRS web interface to 29 March 2012 and thereafter via Metaxis interface to September 2012). There were no language or publication restrictions. We also searched for ongoing trials via ClinicalTrials.gov (to 23 July 2012). Randomised or quasi-randomised controlled trials of at least 12 months duration comparing sealants for preventing caries of occlusal or approximal surfaces of premolar or molar teeth with no sealant or different type of sealant in children and adolescents under 20 years of age. Two review authors independently screened search results, extracted data and assessed trial quality. We calculated the odds ratio (OR) for caries or no caries on occlusal surfaces of permanent molar teeth. For trials with a split-mouth design, the Becker-Balagtas odds ratio was used. For mean caries increment we used the mean difference. All measures are presented with 95% confidence intervals (CI). The quality of the evidence was assessed using GRADE methods. We conducted the meta-analyses using a random-effects model for those

  15. Acute fibrinous and organising pneumonia.

    PubMed

    Gonçalves, João Rocha; Marques, Ricardo; Serra, Paula; Cardoso, Leila

    2017-09-07

    Acute fibrinous and organising pneumonia (AFOP) is a rare histological pattern of interstitial lung disease. The authors describe a 60-year-old woman admitted to the hospital for sustained fever, presenting with an alveolar opacity on chest X-ray, with the presumed diagnosis of community-acquired pneumonia and the onset of antibiotics. Since serological results suggested that Legionella pneumophila was the infectious agent, she was discharged on levofloxacin. A week later, she was again admitted with fever. CT scan showed opacities with crescentic morphology and a central ground-glass area suggestive of cryptogenic organising pneumonia. Microbiological, serological and autoimmunity tests were negative. She underwent surgical lung biopsy that revealed inflammatory infiltrate, macrophage desquamation, fibroblasts proliferation and fibrin deposition in the alveolar spaces, consistent with AFOP. She started corticotherapy with good response. Disease relapsed after prednisolone discontinuation, 10 months later. Currently, the patient is on prednisolone 5 mg/day without clinical and radiological recurrence. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. The effect of fibrin structure on fibrinolysis.

    PubMed

    Gabriel, D A; Muga, K; Boothroyd, E M

    1992-12-05

    Fibrin structure contributes to the regulation of the fibrinolytic rate. As the fibrin fiber size is decreased, the fibrinolytic rate also decreases. Fibrin structure was altered by either changing the ratio of thrombin to fibrinogen, i.e. altering the assembly rate or by adding a fibrin assembly inhibitor, iopamidol. Changes in the fibrinolytic rate were followed by measuring the time dependence of the decrease in the fiber mass/length ratio during fibrinolysis. A measure of the overall fibrinolytic rate was determined from the decrease in the mass/length ratio versus time. An 8-fold reduction in the fibrinolytic rate was seen on decreasing the mass/length ratio from 2.7 x 10(12) daltons/cm to 0.5 x 10(12) daltons/cm. It is shown that thin fibrin fibers have a decreased rate of conversion of plasminogen to plasmin by tissue plasminogen activator and that thin fibrin fibers are lysed more slowly than thick fibrin fibers.

  17. Near-infrared imaging of demineralization under sealants

    NASA Astrophysics Data System (ADS)

    Tom, Henry; Simon, Jacob C.; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

    2014-07-01

    Previous studies have shown that near-infrared (NIR) reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum NIR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study. Images before and after application of sealants were acquired using NIR reflectance and NIR transillumination at wavelengths of 1300, 1460, and 1500 to 1700 nm. Images were also acquired using polarization sensitive optical coherence tomography (OCT) for comparison. The highest contrast for NIR reflectance was at 1460 nm and 1500 to 1700 nm. These NIR wavelengths are coincident with higher water absorption. The clear Delton sealant investigated was not visible in either copolarization or cross-polarization OCT images. The wavelength region between 1500 and 1700 nm yielded the highest contrast of lesions under sealants for NIR reflectance measurements.

  18. Piezoelectric inkjet printing of medical adhesives and sealants

    NASA Astrophysics Data System (ADS)

    Boehm, Ryan D.; Gittard, Shaun D.; Byrne, Jacqueline M. H.; Doraiswamy, Anand; Wilker, Jonathan J.; Dunaway, Timothy M.; Crombez, Rene; Shen, Weidian; Lee, Yuan-Shin; Narayan, Roger J.

    2010-07-01

    Piezoelectric inkjet printing is a noncontact process that enables microscale processing of biological materials. In this research summary, the use of piezoelectric inkjet printing for patterning medical adhesives and sealants, including a two-component polyethylene glycol hydrogel-based medical sealant, an N-butyl cyanoacrylate tissue adhesive, and a mussel adhesive protein biological adhesive, is described The effect of Fe(III) on mussel adhesive protein structure was evaluated by means of atomic force microscopy. The ability to process microscale patterns of medical sealants and adhesives will provide an improvement in tissue joining, including enhanced tissue integrity, reduced bond lines, and decreased adhesive toxicity. Piezoelectric inkjet deposition of medical adhesives and sealants may be used in wound closure, fracture fixation, and microscale vascular surgery.

  19. Fluoride release and uptake abilities of different fissure sealants

    PubMed Central

    Andenna, Gianluigi; Ceci, Matteo; Beltrami, Riccardo; Colombo, Marco; Cucca, Lucia

    2016-01-01

    Background The long-term capability of resin sealants and glass ionomer cements to release fluoride is associated to a reduction in pit and fissure caries. The regular use of fluoride varnishes/toothpastes can result in the absorption of fluoride into the sealant. The objective of the present study was to assess the fluoride release/uptake capacities of different fissure sealants. Material and Methods Three different fissure sealants (Fuji Triage/GC, Fissurit FX/Voco and Grandio Seal/Voco) were examined. Ten discs of each material were prepared. Each disc was incubated with distilled water and then the solution analyzed for diluted for fluoride concentration, using a combination of fluoride electrode (OrionGP 1 S/N 13824, Orion Research Inc, Boston, MA, USA) connected to an expandable ion analyzer (Orion 720A, Orion Research Inc, Boston, MA, USA). Standard curves between 1 and 100 ppm F- were used to calibrate the electrode. Cumulative fluoride release was measured on days 1, 2, 3, 5, 7, 21, 35 and 49, then two different fluoride varnishes/pastes (Profluorid Varnish/Voco, MI Paste Plus/GC), were applied to the sealants tested, and fluoride release (after reuptake) was measured on days 56, 70 and 84. Results Kruskal Wallis test confirmed significant differences in fluoride release between Fuji Triage/GC and Fissurit FX/Voco and Grandio Seal/Voco from day 1 (P < 0.001). The application of fluoride varnish Profluorid Varnish enhanced the fluoride release for all sealants (P < 0.05). MI Paste Plus enhanced the fluoride release for all sealants except for Fuji Triage/GC (P > 0.05). Conclusions The GIC-based sealant (Fuji Triage/GC) released significantly more fluoride than the resin sealants tested. The exposure to the fluoridated varnish (Profluorid Varnish) significantly recharged the sealants tested more than the CPP-ACPF toothpaste (MI Paste Plus). Key words:Fissure sealants, fluoride release, fluoride uptake, glass ionomer cements. PMID:27398179

  20. SafePatch

    SciTech Connect

    Kelley, M.; Elko, S.

    2000-10-01

    Authenticating and upgrading system software plays a critical role in information security, yet practical tools for assessing and installing software are lacking in today's marketplace. The SafePatch tool provides the mechanism of performing automated analysis, notification, distribution, and installation of security patches and related software to network-based computer systems in a vendor-independent fashion. SafePatch assists in the authentication of software by comparing the system's objects with the patch's objects. SafePatch will monitor vendor's sites to determine when new patches are released and will upgrade system software on target systems automatically. This paper describes the design of SafePatch, motivations behind the project and the advantages of SafePatch over existing tools.

  1. Estradiol Transdermal Patch

    MedlinePlus

    Most brands of estradiol transdermal patches are used to treat hot flushes (hot flashes; sudden strong feelings of heat ... different medication that does not contain estrogen. Most brands of estradiol transdermal patches are also sometimes used ...

  2. Metal Patch Antenna

    NASA Technical Reports Server (NTRS)

    Chamberlain, Neil F. (Inventor); Hodges, Richard E. (Inventor); Zawadzki, Mark S. (Inventor)

    2012-01-01

    Disclosed herein is a patch antenna comprises a planar conductive patch attached to a ground plane by a support member, and a probe connector in electrical communication with the conductive patch arranged to conduct electromagnetic energy to or from the conductive patch, wherein the conductive patch is disposed essentially parallel to the ground plane and is separated from the ground plane by a spacing distance; wherein the support member comprises a plurality of sides disposed about a central axis oriented perpendicular to the conductive patch and the ground plane; wherein the conductive patch is solely supported above the ground plane by the support member; and wherein the support member provides electrical communication between the planer conductive patch and the ground plane.

  3. S53P4 bioactive glass and fibrin glue for the treatment of osteochondral lesions of the knee - a preliminary in vivo study in rabbits.

    PubMed

    Zazgyva, AncuŢa Marilena; Gurzu, Simona; Jung, Ioan; Nagy, Örs; Mühlfay, Gheorghe; Pop, Tudor Sorin

    2015-01-01

    The role of the subchondral bone and the importance of treating both bone and cartilage in cases of chondral and osteochondral lesions of the knee have been highly emphasized. There are no current studies on the experimental use of bioactive glass S53P4 (BonAlive®) as granules in the treatment of osteochondral lesions of the knee. Our preliminary study was designed to establish an experimental model and assesses the effect of glass granules fixed with fibrin compared to fibrin alone as fillers of the osteochondral defects created in the weight-bearing and partial weight-bearing regions of the distal femur in six adult rabbits. We found that the size of the distal femur in adult domestic rabbits allows the creation of 4 mm diameter and 5 mm deep osteochondral defects on both the medial femoral condyle and the trochlea, bilaterally, without significantly affecting the activity level of the animals. Retention of the glass granules in the defects was achieved successfully using a commercially available fibrin sealant. At five weeks post-implantation, we found macroscopic and microscopic differences between the four types of defects. The use of bioactive glass S53P4 for filling condylar osteochondral defects in rabbit femora led to the initiation of an early bone repair process, observed at five weeks after implantation, while the filling of trochlear defects with fibrin glue resulted in the appearance of cartilaginous tissue characteristic of endochondral ossification.

  4. Fissure sealants: Knowledge and practice of Yemeni dental practitioners

    PubMed Central

    Al-Maweri, Sadeq Ali; Al-Jamaei, Aisha Ahmed; Halboub, Esam Saleh; Al-Soneidar, Walid Ahmed; Tarakji, Bassel; Alsalhani, Anas

    2016-01-01

    Objectives This study was conducted to evaluate Yemeni dental practitioners' knowledge and practices concerning fissure sealants. Materials and Methods: A modified questionnaire consisted of 25-items was distributed to 500 dentists working in Sana'a City. Descriptive statistics and Chi-square/Fisher's exact tests were used for statistical analyses. Results: The response rate was 74%. Most of the respondents were male (61.3%), general practitioners (84.2%), and had <5 years of clinical experience (48.3%). The respondents showed a reasonable level of knowledge about sealants, with the majority (88%) believed that there is strong scientific evidence about fissure sealants effectiveness and around 90% showed a good understanding of sealant placement instructions. On the other hand, respondents showed insufficient knowledge about sealants clinical practice. Conclusion: Although a high proportion of dental practitioners showed adequate knowledge about dental sealant, following guidelines and standardized procedures in clinical practice is lacking. These emphasize the need for regular continuing education courses for dental professional. PMID:27095903

  5. Fluoride concentration from dental sealants: a randomized clinical trial.

    PubMed

    Campus, G; Carta, G; Cagetti, M G; Bossù, M; Sale, S; Cocco, F; Conti, G; Nardone, M; Sanna, G; Strohmenger, L; Lingström, P

    2013-07-01

    A randomized clinical trial was performed in schoolchildren (6-7 yrs) to evaluate fluoride concentration in interproximal fluid after the placement of 3 different sealants. The sample consisted of 2,776 children randomly divided: 926 in the high-viscosity Glass-ionomer Cement group (GIC group), 923 in the fluoride Resin-based group (fluoride-RB group), and 927 in the no-fluoride Resin-based group (RB group). In total, 2,640 children completed the trial. Sealants were applied following manufacturer's instructions. Interproximal fluid samples were collected at baseline and 2, 7, and 21 days after application of sealants, by insertion of a standardized paperpoint into the interproximal mesial space of the sealed tooth for 15 seconds. Fluoride concentration was evaluated by means of a fluoride ion-selective electrode. At 2 days after sealant application, fluoride concentration was significantly higher in GIC and fluoride-RB groups compared with that in the RB group (p < .01). Mean fluoride concentrations after 7 days were 2.54 (SE 0.68) ppm, 0.85 (SE 0.26) ppm, and 0.53 (SE 0.11) ppm for the three groups, respectively. After 21 days, fluoride concentration in the GIC group remained higher than that in the other two groups. High-viscosity GIC sealants increased the fluoride concentrations in interproximal fluid more than did a Resin-based sealant containing fluoride.

  6. Sealant use and dental utilization in U.S. children.

    PubMed

    Cherry-Peppers, G; Gift, H C; Brunelle, J A; Snowden, C B

    1995-01-01

    The use of dental sealants has remained relatively low in the U.S. in comparison with other proven oral disease preventive therapies, and particularly among black children. Dental visits have also been consistently lower among black children. This paper describes the reported use of dental sealants and dental visits in U.S. children ages 6-17 using data from the 1989 National Health Interview Survey (NHIS). Family income and education interact with race in explaining the use of dental sealants and dental visits. Racial differences in sealant use and dental visits are more apparent in middle and upper socioeconomic levels, than lower socioeconomic level children. Overall, 15 percent of children ages 6-17 have dental sealants and 73 percent had a dental visit in the past twelve months. More white children whose parents had higher income levels and at least one year of undergraduate education (24 percent) had sealants than similar socioeconomic status (SES) black children (11 percent). Additionally, black children whose parents had a college education (68 percent) were less likely to have dental visits during the past 12 months than white children of similar SES (86 percent). These results provide an opportunity to evaluate factors and conditions that could form a basis of targeting programs to improve behaviors, attitudes, as well as access to preventive dental services.

  7. Impact of Wisconsin Medicaid Policy Change on Dental Sealant Utilization.

    PubMed

    Okunseri, Christopher; Okunseri, Elaye; Garcia, Raul I; Gonzalez, Cesar; Visotcky, Alexis; Szabo, Aniko

    2016-12-12

    In September 2006, Wisconsin Medicaid changed its policy to allow nondentists to become certified Medicaid providers and to bill for sealants in public health settings. This study examined changes in patterns of dental sealant utilization in first molars of Wisconsin Medicaid enrollees associated with a policy change. The Electronic Data Systems of Medicaid Evaluation and Decision Support for Wisconsin from 2001 to 2009. Retrospective claims data analysis of Wisconsin Dental Medicaid for children aged 6-16 years. A total of 479,847 children followed up for 1,441,300 person-years with 64,546 visits were analyzed. The rate of visits for sealants by dentists increased significantly from 3 percent per year prepolicy to 11 percent per year postpolicy, and that of nondentists increased from 18 percent per year to 20 percent after the policy change, but this was not significant. Non-Hispanic blacks had the lowest visit rates for sealant application by dentists and nondentists pre- and postpolicy periods. The Wisconsin Medicaid policy change was associated with increased rates of visits for dental sealant placement by dentists. The rate of visits with sealant placements by nondentists increased at the same rate pre- and postpolicy change. © Health Research and Educational Trust.

  8. Birth Control Patch

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Birth Control Patch KidsHealth > For Teens > Birth Control Patch Print A A A What's in this ... Much Does It Cost? What Is It? The birth control patch is a thin, beige, 1¾-inch (4½- ...

  9. Birth Control Patch

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Birth Control Patch KidsHealth > For Teens > Birth Control Patch A A A What's in this article? ... Much Does It Cost? What Is It? The birth control patch is a thin, beige, 1¾-inch (4½- ...

  10. Structural hierarchy governs fibrin gel mechanics.

    PubMed

    Piechocka, Izabela K; Bacabac, Rommel G; Potters, Max; Mackintosh, Fred C; Koenderink, Gijsje H

    2010-05-19

    Fibrin gels are responsible for the mechanical strength of blood clots, which are among the most resilient protein materials in nature. Here we investigate the physical origin of this mechanical behavior by performing rheology measurements on reconstituted fibrin gels. We find that increasing levels of shear strain induce a succession of distinct elastic responses that reflect stretching processes on different length scales. We present a theoretical model that explains these observations in terms of the unique hierarchical architecture of the fibers. The fibers are bundles of semiflexible protofibrils that are loosely connected by flexible linker chains. This architecture makes the fibers 100-fold more flexible to bending than anticipated based on their large diameter. Moreover, in contrast with other biopolymers, fibrin fibers intrinsically stiffen when stretched. The resulting hierarchy of elastic regimes explains the incredible resilience of fibrin clots against large deformations.

  11. Structural Hierarchy Governs Fibrin Gel Mechanics

    PubMed Central

    Piechocka, Izabela K.; Bacabac, Rommel G.; Potters, Max; MacKintosh, Fred C.; Koenderink, Gijsje H.

    2010-01-01

    Abstract Fibrin gels are responsible for the mechanical strength of blood clots, which are among the most resilient protein materials in nature. Here we investigate the physical origin of this mechanical behavior by performing rheology measurements on reconstituted fibrin gels. We find that increasing levels of shear strain induce a succession of distinct elastic responses that reflect stretching processes on different length scales. We present a theoretical model that explains these observations in terms of the unique hierarchical architecture of the fibers. The fibers are bundles of semiflexible protofibrils that are loosely connected by flexible linker chains. This architecture makes the fibers 100-fold more flexible to bending than anticipated based on their large diameter. Moreover, in contrast with other biopolymers, fibrin fibers intrinsically stiffen when stretched. The resulting hierarchy of elastic regimes explains the incredible resilience of fibrin clots against large deformations. PMID:20483337

  12. Effectiveness of two new types of sealants: retention after 2 years.

    PubMed

    Chen, Xi; Du, Minquan; Fan, Mingwen; Mulder, Jan; Huysmans, Marie-Charlotte; Frencken, Jo E

    2012-10-01

    The hypotheses tested were: survival rate of fully and partially retained glass-carbomer sealants is higher than those of high-viscosity glass-ionomer, with and without energy supplied, and that of resin composite; survival rate of fully and partially retained sealants of high-viscosity glass-ionomer with energy supplied is higher than those without energy supplied. The randomized clinical trial covered 407 children, with a mean age of 8 years. The evaluation took place after 0.5, 1 and 2 years. Survival of sealant material in occlusal and in smooth surfaces, using the traditional categorization (fully and partially retained versus completely lost sealants) and the modified categorization (fully and more than 2/3 of the sealant retained versus completely lost sealants), were dependent variables. The Kaplan-Meier survival method was used. According to both categorizations of partially retained sealants, the survival of completely and partially retained resin composite sealants in occlusal and in smooth tooth surfaces was statistically significantly higher, and those of glass-carbomer sealants lower, than those of sealants of the other three groups. There was no statistically significant difference in the survival rates of completely and partially retained high-viscosity glass-ionomer sealants with and without energy supplied in occlusal and in smooth surfaces. After 2 years, glass-carbomer sealant retention was the poorest, adding energy to high-viscosity glass-ionomer sealant did not increase the retention rate and resin composite sealants were retained the longest. We suggest the use of the modified categorization of partially retained sealants in future studies. It seems not necessary to cure high-viscosity glass-ionomer sealants. The use of glass-carbomer sealants cannot be recommended yet.

  13. Technology Solutions Case Study: Ducts Sealing Using Injected Spray Sealant

    SciTech Connect

    2014-03-01

    In multifamily and attached buildings, traditional duct sealing methods are often impractical or costly and disruptive because of the difficulty in accessing leakage sites. In this project, the Raleigh Housing Authority worked with Building America team, the Advanced Residential Integrated Solutions Collaborative to determine the most cost-effective ways to reduce duct leakage in its low-rise housing units.Two retrofit duct sealing techniques—manually-applied sealants and injecting a spray sealant—were implemented in several low-rise multiunit buildings. An analysis on the cost and performance of the two methods are presented. Each method was used in twenty housing units: approximately half of each group of units are single story and the remainder two-story. Results show that duct leakage to the outside was reduced by an average of 59% through the use of manual methods, and by 90% in the units where the injected spray sealant was used. Ihe cost of manually-applying sealant ranged from $275 to $511 per unit and for the injected spray sealant the cost was $700 per unit. Modeling suggests a simple payback of 2.2 years for manual sealing and 4.7 years for the injected spray sealant system. Utility bills were collected for one year before and after the retrofits. Utility bill analysis shows 14% and 16% energy savings using injected spray sealant system and hand sealing procedure respectively in heating season whereas in cooling season, energy savings using injected spray sealant system and hand sealing were both 16%.

  14. The depth of cure of clear versus opaque sealants as influenced by curing regimens.

    PubMed

    Yue, Christopher; Tantbirojn, Daranee; Grothe, Ronald L; Versluis, Antheunis; Hodges, James S; Feigal, Robert J

    2009-03-01

    The authors conducted a study to test the hypothesis that light-curing regimens affect depth of cure of clear versus opaque sealants. The authors light-cured samples of one clear and two opaque sealants at 20 seconds, 0 millimeters; 40 seconds, 0 mm; and 40 seconds, 2.2 mm (n = 5 each). They assessed the depth of cure with Knoop hardness at 0.5-mm increments five minutes and one hour after curing. The authors used analysis of variance. Curing regimens and sealant types affected the depth of cure. The clear sealant maintained a greater hardness than did the opaque sealants through a depth of 3 mm (P < .001). A 20-second duration reduced the depth of cure for all sealants (P < .001). The distance from the light source did not affect the cure depth of the clear sealant (P = .34), but it reduced the cure depth of the opaque sealants (P < .05). Sealant hardness increased significantly one hour after light curing (P < .001). A clear sealant cured deeper than did opaque sealants. Curing duration is crucial to achieve an adequate depth of cure. A 20-second duration may not suffice. Light source distance affected the depth of cure for the opaque sealants, but not for the clear sealant with sufficient curing duration. The authors advocate a curing duration of longer than 20 seconds to ensure thorough polymerization at the interface between the sealant and tooth. Insufficient curing could contribute to failure of the sealants, especially the opaque sealants, under clinical conditions that restrict the light tip position.

  15. Sealant microleakage after using nano-filled bonding agents on saliva-contaminated enamel.

    PubMed

    Paryab, Mehrsa

    2013-05-01

    The efficacy of correctly applied fissure sealants has been revealed in the prevention of caries. Saliva and moisture contamination of the etched enamel surface before sealant placement can decrease the bonding strength of the sealant to the enamel. The aim of this study was to test the new bonding agents containing nano-fillers in order to reduce the negative effect of saliva contamination on the sealant micro leakage. Seventy five sound human premolars were randomly assigned to five equal groups as follows: Group A: etching, sealant; Group B: etching, saliva contamination, sealant; Group C: etching, saliva contamination, Single bond, sealant; Group D: etching, saliva contamination, Adper Single bond 2, sealant; Group E: etching, saliva contamination, N Bond, sealant. The samples were thermo-cycled and immersed in basic fuchsine 0.5% by weight. Then, the teeth were sectioned bucco-lingually and parallel to the long axis into two segments. Finally, the length of dye penetration at the sealant-tooth interface was scored according to a four-point scale. Micro-leakage was higher in group B compared to the other groups, while there were no differences among the evaluated dentin adhesives. The use of nano-filled bonding agents as an intermediate layer between the etched enamel and the sealant can reduce sealant micro-leakage after saliva contamination at the level of the uncontaminated enamel.

  16. Fibroblast migration in fibrin gel matrices.

    PubMed Central

    Brown, L. F.; Lanir, N.; McDonagh, J.; Tognazzi, K.; Dvorak, A. M.; Dvorak, H. F.

    1993-01-01

    In healing wounds and many solid tumors, locally increased microvascular permeability results in extravasation of fibrinogen and its extravascular coagulation to form a fibrin gel, with concomitant covalent cross-linking of fibrin by factor XIIIa. Subsequently, inflammatory cells, fibroblasts, and endothelial cells migrate into the gel and organize it into granulation tissue and later into mature collagenous connective tissue. To gain insight into some of the cell migration events associated with these processes, we developed a quantitative in vitro assay that permits the study of fibroblast migration in fibrin gels. Early passage human or rat fibroblasts were allowed to attach to tissue culture dishes and then were overlaid with a thin layer of fibrinogen that was clotted with thrombin. Fibroblasts began to migrate upwards into the fibrin within 24 hours and their numbers and the distance migrated were quantified over several days. The extent of fibroblast migration was affected importantly by the nature of the fibrin clot. Fibroblasts migrated optimally into gels prepared from fibrinogen at concentrations of -3 mg/ml; ie, near normal plasma fibrinogen levels. Migration was greatly enhanced by extensive cross-linking of the fibrin alpha-chains by factor XIIIa, as occurs when clotting takes place in vivo. When fibrinogen was clotted in Dulbecco's modified Eagle's medium, gamma-chains were cross-linked, but alpha-chain cross-linking was strikingly inhibited, and fibroblasts migrated poorly. Gels prepared from factor XIII-depleted fibrinogen exhibited neither alpha-nor gamma-chain cross-linking and did not support fibroblast migration. Further purification of fibrinogen by anion exchange high pressure liquid chromatography depleted fibrinogen of fibronectin, plasminogen, and other impurities; this purified fibrinogen clotted to form fibrin gels that supported reproducible fibroblast migration. Images Figure 1 Figure 2 Figure 4 Figure 6 PMID:8424460

  17. Retention of a resin-based sealant and a glass ionomer used as a fissure sealant in children with special needs

    PubMed Central

    Nualart-Grollmus, Zacy-Carola

    2014-01-01

    Objectives: The aim of this research is to evaluate the retention of sealants of resin and resin-modified ionomeric glass pits and fissures, on first permanent molars of special patients. Material and Methods: The sample was comprised by 32 children. The ages were between 7 and 18 years. The sealing procedure was made with the relative isolation of the molars to be sealed, through the use of cotton rolls. Two molars were sealed with Clinpro Sealant 3M Dental and the others with Vitremer. Checking of the sealants was made after 3 and 6 months of their placement, evaluating with 3 values: TR: Totally Restrained; PR: Partially Restrained; and CL: Completely Lost. Results: 67.18% of the resinous sealants, and 70.31% of the glass ionomer sealants were successful after three months. After six months, 57.81% of the resin-based sealants and 51.56% of the glass ionomer sealants were successful. When performing the Chi-square statistical analysis (P<0.05) no statistical significance was observed after 6 months. Conclusions: The retention of the resin sealant was similar to that of the glass ionomer cement at the end of six months and the retention of sealants on maxillary teeth was higher than on mandibular teeth. Key words:Sealant, glass ionomer, retention, caries, special needs. PMID:25674325

  18. Sealants in dentistry: a systematic review of the literature.

    PubMed

    Condò, R; Cioffi, A; Riccio, A; Totino, M; Condò, S G; Cerroni, L

    2013-03-01

    The occlusal surface is the most affected area by dental caries and the sealing of the pits and of the fissures has been found, in time, the preventive method most effective trying to counteract the onset. Currently, the WHO considers it as a primary preventive measure, in other words one of the most effective and least invasive available to ensure the complete protection and the total preservation of the occlusal carious by the phenomenon. THE AIM OF THIS WORK HAS BEEN TO PERFORM A SYSTEMATIC REVIEW OF THE LITERATURE ON CLINICAL TRIALS OF DIFFERENT SEALING MATERIALS, IN ORDER TO: compare their individual characteristics, highlight the reliability and the long-term efficacy and identify the most significant variables, both technological and clinics, in order to declare whether or not the success of this method prior. The research has been carried out in the MEDLINE database by choosing keywords as "sealants" and "follow up". Only studies published in the last thirteen years have been considered and have been evaluated only types of scientific articles that fall within the definition of Anglo-Saxon "Clinical Trial" and "Controlled Clinical Trial", excluding all experimental works in vitro, case-reports, meta-analyzes and literature reviews. Have been also considered only scientific papers on patients between the ages of 0 and 18 years. Out of 29 studies, evaluating a total of 2900 individuals (aged between 2.5 and 17 years), 7411 seals made by using resin-based sealants (RB Sealants), modified glass ionomer sealants (RMGI) and compomer sealants have been analyzed. The best retention capacity of the material in time has been obtained from the use of RB Sealants compared to RMGI, demonstrating retention values much lower with partial loss of material at a distance of one year from the clinic. The compomers demonstrate retention values intermediates. The incidence of caries in a year is negligible for all sealants application. In terms of retention, resin

  19. Acceptability of fissure sealants from the child's perspective.

    PubMed

    Morgan, A G; Madahar, A K; Deery, C

    2014-07-11

    To seek children's opinions about the acceptability of resin fissure sealant placement. Service evaluation using a child-centred questionnaire issued to a prospective sample of consecutive hospital patients.Method Questionnaires were issued to children, aged 3 to 16 years, immediately after resin fissure sealant placement in the Paediatric Dentistry Department in Sheffield. Participants used a three-point faces scale for positive, neutral and negative responses, arranged as a Likert scale with minimal text, to rate their treatment experiences and satisfaction with the dental visit. Two hundred questionnaires were returned. Overall, 96% (n = 191) recorded a positive or neutral response for the ease at which they coped with the procedure, with most children positive about having fissure sealants placed again (66%; n = 132). Further analysis demonstrated that children who had fissure sealants on a previous occasion found them easier than those having them for the first time (p <0.05, chi-squared test). Almost half of all participants where ambivalent about the taste and feeling (46%; n = 92 and 55%; n = 110 respectively). The vast majority of children were satisfied with the explanations provided by their operator. Most participants found having resin fissure sealants placed an overall acceptable procedure, with patient acceptance improving with increased treatment experience.

  20. Flow characteristics and sealing ability of fissure sealants.

    PubMed

    Barnes, D M; Kihn, P; von Fraunhofer, J A; Elsabach, A

    2000-01-01

    This study evaluated the relationship between fissure sealant viscosity, leakage prevention and the incidence of void formation of five commercially available pit-and-fissure sealants. Seventy-two intact, caries free human pre-molars and molars were divided into six test groups of 12 teeth each. All teeth were cleaned with a flour of pumice prophylaxis followed by etching for 60 seconds with 37% H3PO4, rinsing for 30 seconds and drying with oil-free air. Five commercial, light-cured fissure sealants and an unfilled version of one sealant were applied following manufacturers' instructions. Teeth were thermal cycled for 5000 cycles from 5-50 degrees C with a one-minute dwell time at each temperature. Silver nitrate staining followed by mesiodistal sectioning was performed. Leakage and void formation were evaluated at X50 optical magnification. Viscosity was assessed by syringing the fissure sealants into short pipettes, allowing free flow for 30 seconds and then light curing for one minute. The length of unfilled capillary was measured with a Vernier gauge. All experimental data was subjected to a one-way ANOVA, and where differences were detected, they were identified by a post hoc Tukey hsd test at a priori alpha = 0.05. Based on the conditions of the study, viscosity and flow characteristics had no effect on sealing ability or void formation.

  1. Zinc modulates thrombin adsorption to fibrin

    SciTech Connect

    Hopmeier, P.; Halbmayer, M.; Fischer, M.; Marx, G. )

    1990-05-01

    Human thrombin with high affinity to Sepharose insolubilized fibrin monomers (high-affinity thrombin) was used to investigate the effect of Zn(II) on the thrombin adsorption to fibrin. Results showed that at Zn(II) concentrations exceeding 100 mumols/l, thrombin binding to fibrin was decreased concomitant with the Zn(II) concentration and time; at lower Zn(II) concentrations, thrombin adsorption was enhanced. Experimental results were identical by using 125I-labelled high-affinity alpha-thrombin or by measuring the thrombin activity either by chromogenic substrate or by a clotting time method. In contrast, Ca(II) alone (final conc. 3 mmol/l) or in combination with Zn(II) was not effective. However, at higher Ca(II) concentrations (7.5-15 mmol/l), thrombin adsorption was apparently decreased. Control experiments revealed that Zn(II) had no impact on the clottability of fibrinogen, and that the results of the experiments with Ca(II) were not altered by possible cross-linking of fibrin. We conclude that unlike Ca(II), Zn(II) is highly effective in modulating thrombin adsorption to fibrin.

  2. Biological evaluation of enamel sealants in an organotypic model of the human gingiva.

    PubMed

    Zingler, Sebastian; Matthei, Byron; Diercke, Katja; Frese, Cornelia; Ludwig, Björn; Kohl, Annette; Lux, Christopher J; Erber, Ralf

    2014-09-01

    Various sealant materials have been suggested to decrease decalcification during orthodontic treatment. However, only a few in vitro studies on the cytotoxicity of resinous pit and fissure sealants have been published, and to the best of our knowledge no similar studies are available for the enamel sealants used in orthodontics. Therefore, we aimed to characterize the possible adverse effects of enamel sealants, especially on the gingival epithelium. Organotypic cultures of the human gingival mucosa were used to assess the possible impact of six enamel sealants. Differentiation and apoptosis were determined by immunofluorescent staining. The pro-inflammatory cytokines IL-1β and IL-6 were quantified by ELISA. Cytotoxicity was measured using MTS assays in monolayer cultures of human gingival fibroblasts. Leaching of monomers from enamel sealants was quantified using HPLC. The differentiation of the organotypic gingival mucosa remained unaffected. All under-cured and several standard-cured sealants (Light Bond™ Sealant, Light Bond™ Filled Sealant, and L.E.D. Pro Seal®) significantly induced apoptosis in the organotypic model. Light Bond™ Sealant, Light Bond™ Filled Sealant, and L.E.D. Pro Seal® caused a significant induction of pro-inflammatory cytokines. Reducing curing time had an influence on cytotoxicity in monolayer cultures of primary human oral cells. All resin-based sealants leached monomers. Enamel sealants might exert adverse effects on the gingival epithelium. Due to the vicinity of the enamel sealant to the gingival epithelium, and the large surface area of applied sealants, these materials should be carefully applied and sufficiently cured. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. Glass ionomer ART sealant and fluoride-releasing resin sealant in fissure caries prevention – results from a randomized clinical trial

    PubMed Central

    2014-01-01

    Background The relative performance of ART sealant and fluoride-releasing resin sealant in preventing fissure caries in permanent molars was compared in a randomized clinical trial conducted in southern China (ClinicalTrials.gov NCT01829334). Methods After obtaining ethical approval, healthy schoolchildren who had permanent first molars with occlusal fissures which were sound but deep or presented with only incipient caries were recruited for the study. Included molars were randomly allocated into one of four parallel study groups in units of left/right teeth per mouth. Two of the four groups adopted the methods of ART or fluoride-releasing resin sealant placement while the other two groups adopted the topical fluoride application methods. Fissure status of the molars in each group was evaluated every 6 months. Development of dentine caries and sealant retention over 24 months in the molars in the two sealant-using groups was compared in this report. Outcome on cost-effectiveness of all four groups over 36 months will be reported elsewhere. Results At baseline, a total of 280 children (383 molars) with mean age 7.8 years were involved for the two sealant groups. After 24 months, 261 children (357 molars) were followed. Proportions of molars with dentine caries were 7.3% and 3.9% in the ART sealant and fluoride-releasing resin sealant groups, respectively (chi-square test, p = 0.171). Life-table survival analysis showed that sealant retention (full and partial) rate over 24 months for the resin sealant (73%) was significantly higher than that (50%) for the ART sealant (p < 0.001). Molar survival (no development of dentine caries) rates in the ART sealant (93%) and fluoride-releasing resin sealant (96%) groups were not significantly different (p = 0.169). Multilevel logistic regression (GEE modeling) accounting for the effects of data clustering and confounding factors confirmed this finding. Conclusions Though the retention of fluoride

  4. Continuing sources of PCBs: the significance of building sealants.

    PubMed

    Robson, Matthew; Melymuk, Lisa; Csiszar, Susan A; Giang, Amanda; Diamond, Miriam L; Helm, Paul A

    2010-08-01

    To investigate the significance of building sealants as a remaining source of PCBs to the environment a combined measurement campaign and GIS-based stock estimation were undertaken for Toronto, Canada. This showed that 14% of buildings measured had detectable quantities of PCBs present in sealants, with concentrations from 0.57 mg/g to 82 mg/g (n=95). We then constructed a GIS-based database of remaining PCB-containing sealants in Toronto. This showed that there is an estimated 13 t still present in the city. Mass balance calculations showed that up to 9% had been lost via volatilization alone. This potentially has important implications for both human exposure and the continued presence of PCBs in the environment. Copyright 2010 Elsevier Ltd. All rights reserved.

  5. Sealants in dentistry: a systematic review of the literature

    PubMed Central

    CONDÒ, R.; CIOFFI, A.; RICCIO, A.; TOTINO, M.; CONDÒ, S.G.; CERRONI, L.

    2013-01-01

    SUMMARY The occlusal surface is the most affected area by dental caries and the sealing of the pits and of the fissures has been found, in time, the preventive method most effective trying to counteract the onset. Currently, the WHO considers it as a primary preventive measure, in other words one of the most effective and least invasive available to ensure the complete protection and the total preservation of the occlusal carious by the phenomenon. Purpose. The aim of this work has been to perform a systematic review of the literature on clinical trials of different sealing materials, in order to: compare their individual characteristics, highlight the reliability and the long-term efficacy and identify the most significant variables, both technological and clinics, in order to declare whether or not the success of this method prior. Materials and methods. The research has been carried out in the MEDLINE database by choosing keywords as “sealants” and “follow up”. Only studies published in the last thirteen years have been considered and have been evaluated only types of scientific articles that fall within the definition of Anglo-Saxon “Clinical Trial” and “Controlled Clinical Trial”, excluding all experimental works in vitro, case-reports, meta-analyzes and literature reviews. Have been also considered only scientific papers on patients between the ages of 0 and 18 years. Results. Out of 29 studies, evaluating a total of 2900 individuals (aged between 2.5 and 17 years), 7411 seals made by using resin-based sealants (RB Sealants), modified glass ionomer sealants (RMGI) and compomer sealants have been analyzed. The best retention capacity of the material in time has been obtained from the use of RB Sealants compared to RMGI, demonstrating retention values much lower with partial loss of material at a distance of one year from the clinic. The compomers demonstrate retention values intermediates. The incidence of caries in a year is negligible for all

  6. Dental sealant knowledge, opinion, values and practice of Spanish dentists

    PubMed Central

    2013-01-01

    Background Multiple guidelines and systematic reviews recommend sealant use to reduce caries risk. Yet, multiple reports also indicate that sealants are significantly underutilized. This study examined the knowledge, opinions, values, and practice (KOVP) of dentists concerning sealant use in the southwest region of Andalusia, Spain. This is a prelude to the generation of a regional plan for improving children’s oral health in Andalusia. Methods The survey’s target population was dentists working in western Andalusia, equally distributed in the provinces of Seville, Cadiz, and Huelva (N=2,047). A convenience sample of meeting participants and meeting participant email lists (N=400) were solicited from the annual course on Community and Pediatric Dentistry. This course is required for all public health sector dentists, and is open to all private sector dentists. Information on the dentist’s KOVP of sealants was collected using four-part questionnaire with 31, 5-point Likert-scaled questions. Results The survey population demographics included 190 men (48%) and 206 women (52%) with an average clinical experience of 10.6 (± 8.4) years and 9.3 (± 7.5) years, respectively. A significant sex difference was observed in the distribution of place of work (urban/suburb) (p=0.001), but no sex differences between working sector (public/private). The mean ± SD values for each of the four KOVP sections for pit and fissure sealants were: knowledge = 3.57 ± 0.47; opinion = 2.48 ± 0.47; value = 2.74 ± 0.52; and practice = 3.48 ± 0.50. No sex differences were found in KOVP (all p >0.4). Independent of sex: knowledge statistically differed by years of experience and place of work; opinion statistically differed by years of experience and sector; and practice statistically differed by years of experience and sector. Less experienced dentists tended to have slightly higher scores (~0.25 on a Likert 1–5 scale). Statistically significant correlations were found between

  7. Safety and usability of hemostats, sealants, and adhesives.

    PubMed

    Burks, Sandra; Spotnitz, William

    2014-08-01

    Hemostats, sealants, and adhesives are an integral part of surgical patient care. Nurses who have knowledge about these agents can better help ensure safe, efficient surgical patient care. As a caregiver and patient advocate, the perioperative nurse must understand the most current information about these agents and be prepared to facilitate the transfer of this knowledge to all caregivers. Information about these agents, including the contraindications, warnings, and precautions associated with their use as well as their preparation and application, is provided here. Algorithms designed to clarify the best options for using hemostats, sealants, and adhesives are included as well.

  8. Reimbursement rates and policies for primary molar pit-and-fissure sealants across state Medicaid programs.

    PubMed

    Chi, Donald L; Singh, Jennifer

    2013-11-01

    Little is known about Medicaid policies regarding reimbursement for placement of sealants on primary molars. The authors identified Medicaid programs that reimbursed dentists for placing primary molar sealants and hypothesized that these programs had higher reimbursement rates than did state programs that did not reimburse for primary molar sealants. The authors obtained Medicaid reimbursement data from online fee schedules and determined whether each state Medicaid program reimbursed for primary molar sealants (no or yes). The outcome measure was the reimbursement rate for permanent tooth sealants (calculated in 2012 U.S. dollars). The authors compared mean reimbursement rates by using the t test (α = .05). Seventeen Medicaid programs reimbursed dentists for placing primary molar sealants (34 percent), and the mean reimbursement rate was $27.57 (range, $16.00 [Maine] to $49.68 [Alaska]). All 50 programs reimbursed dentists for placement of sealants on permanent teeth. The mean reimbursement for permanent tooth sealants was significantly higher in programs that reimbursed for primary molar sealants than in programs that did not ($28.51 and $23.67, respectively; P = .03). Most state Medicaid programs do not reimburse dentists for placing sealants on primary molars, but programs that do so have significantly higher reimbursement rates. Medicaid reimbursement rates are related to dentists' participation in Medicaid and children's dental care use. Reimbursement for placement of sealants on primary molars is a proxy for Medicaid program generosity.

  9. Plaque and saliva fluoride levels after placement of fluoride releasing pit and fissure sealants.

    PubMed

    Rajtboriraks, Daranee; Nakornchai, Siriruk; Bunditsing, Panit; Surarit, Rudee; Iemjarern, Piyarat

    2004-01-01

    The objectives of this study were to investigate the fluoride levels in plaque and saliva before and after applying fluoride-containing pit and fissure sealants, and compare the fluoride release of 2 types of sealants at the different time intervals. Eighteen children ages 6 to 9 years were randomly divided into 2 groups: Group 1--sealant containing fluorosilicate glass (Helioseal-F); and group 2--sealant containing methacryloyl fluoride-methyl methacrylate copolymer (Teethmate-F). Saliva and plaque samples were collected before and after the sealants were placed on their 4 first permanent molars. Fluoride levels were determined using the microdiffusion method. Fluoride concentrations before and after placing the sealants were analyzed by paired t test, and the fluoride concentrations between the 2 sealants were compared by t test, with the level of significance at 0.05. There was no significant difference between salivary fluoride levels before and after sealant placement application in both groups. The plaque fluoride level of Helioseal-F group at 24 hours was significantly higher than the baseline level (P = .03), and was not different afterwards. The plaque fluoride levels after sealant with Teethmate-F were not significantly different when compared to the baseline. However, there were no significant differences between salivary and plaque fluoride levels of the 2 groups at different time intervals. The groups sealed with sealant containing fluorosilicate glass showed significant increase of plaque fluoride level only at 24 hours after sealant placement.

  10. The Effect of Fluoride Varnish on Enamel Shear Bond Strength of Pit and Fissure Sealants.

    PubMed

    Frazer, Rebecca A; Platt, Jeffrey A; Sanders, Brian J; Yepes, Juan F; Jones, James E

    2017-03-15

    The purpose of this study was to determine the effects of fluoride varnish on the enamel shear bond strength of pit and fissure sealants. Ninety-six teeth were divided into three duplicated test groups: sealant (S)/sealant thermocycle (ST) received Clinpro Sealant only; varnish sealant (VS)/varnish sealant thermocycle (VST) received five percent sodium fluoride (NaF) varnish plus sealant (VPS); and VPS/VPS thermocycle (VPST) received NaF, polish with Clinpro Prophy Paste, plus sealant. One set of each group (ST, VST, VPST) was thermocycled to represent aging, and one set (S, VS, PVS) was not. The shear bond strengths for the thermocycled groups and nonthermocycled groups were determined, and two-way analysis of variance tested the effects of thermocycling and varnish. Thermocycling did not have a significant effect on the peak stresses of the groups (P=0.0552), so sets were combined. The peak stress for S/ST was significantly higher than for VS/VST (P<0.0001). The peak stress for VPS/VPST was significantly higher than for VS/VST (P<0.0001). The peak stress for S/ST was significantly higher than VPS/VPST (P=0.025). Fluoride varnish applied immediately before pit and fissure sealant placement negatively affected the shear bond strength of the sealant. Mechanically cleaning a fluoride varnish-coated tooth with prophy paste did not provide pit and fissure sealant enamel shear bond strengths comparable to those of untreated enamel.

  11. Microleakage and shear bond strength of a new sealant containing prereacted glass ionomer particles.

    PubMed

    Durham, Samuel N; Meyers, Erik J; Bailey, Clifton W; Vandewalle, Kraig S

    2017-01-01

    A new fluoride-releasing sealant system is claimed to allow easier and faster placement while providing high bond strengths without the need for phosphoric acid etching. A study was designed to compare the microleakage and shear bond strength of a self-etching, Giomer-based sealant system with those of a traditional resin sealant. Group 1 received traditional sealant applied after use of a 35% phosphoric acid etchant; group 2 received Giomer sealant after use of a self-etching primer; and group 3 received Giomer sealant after the addition of an initial phosphoric acid etching step and placement of the primer. The sealants were placed in the occlusal pits and fissures of extracted human third molars, thermocycled, placed in dye, and sectioned. The extent of microleakage (dye penetration) was expressed as a percentage of the cross-sectional length of the sealed interface. The sealants were also bonded to the facial enamel of bovine incisors. Specimens were thermocycled and tested in shear mode in a universal testing machine. The new self-etching sealant demonstrated significantly greater microleakage (P < 0.017) and lower bond strength (P < 0.05) than both the traditional sealant system and the new system when placed with phosphoric acid etchant. Phosphoric acid etching significantly improved the shear bond strength and reduced the microleakage of the new sealant.

  12. Sealants in dentistry: outcomes of the ORCA Saturday Afternoon Symposium 2007.

    PubMed

    Splieth, C H; Ekstrand, K R; Alkilzy, M; Clarkson, J; Meyer-Lueckel, H; Martignon, S; Paris, S; Pitts, N B; Ricketts, D N; van Loveren, C

    2010-01-01

    Sealants are a successful tool in caries prevention, but their role in preventive strategies after the caries decline has to be discussed. A survey of paediatric departments across Europe revealed that indications for pit and fissure sealants vary considerably, both nationally and internationally. Evidence for effectiveness of sealants in controlling caries in posterior teeth implies that sealants should be an integrated part of management of pit and fissure caries. Still, the indication for occlusal sealants seems to be shifting from primary prevention to a therapeutic decision for caries management of lesions in enamel and the outer part of the dentine. Sealants are also an interesting concept for caries management in approximal surfaces. Clinical trials suggest that novel techniques of sealing or infiltrating approximal lesions show promise. However, approximal sealing techniques are as complex to apply and time-consuming as approximal fillings. The article proposes guidelines for teaching on the use of sealants. Copyright 2009 S. Karger AG, Basel.

  13. Ability Of Optical Coherence Tomography To Detect Caries Beneath Commonly Used Dental Sealants

    PubMed Central

    Osann, Kathryn; Pharar, Jessica; Lee, Kenneth; Ahn, Yeh-chan; Tucker, Travis; Sabet, Sharareh; Chen, Zhongping; Gukasyan, Ripsik; Wilder-Smith, Petra

    2010-01-01

    Background and Objective The onset and progression of early tooth decay is often preventable with dental sealants. However, occasionally decay progresses underneath the sealant. Current technology does not permit monitoring of potential lesion progression or arrest. Dental sealants themselves mask the visual cues that identify early tooth decay, and radiographs are not sufficiently sensitive. Therefore clinicians can be reluctant to use dental sealant. The objective of this ex vivo study was to evaluate the ability of dentists to detect decay beneath commonly used dental sealants using Optical Coherence Tomography (OCT) imaging. Study Designs/Materials/Methods Forty extracted teeth were divided into equal groups of carious and non-carious teeth, as determined by visual inspection. After radiographs and OCT imaging, teeth were randomly assigned for sealant placement with one of four commonly purchased dental sealants: Clinpro™, Fuji Triage™, Embrace Wet Bond™, and Delton™. Following sealant placement, teeth were radiographed, imaged with OCT, sectioned, examined histologically, and scored as healthy/not healthy. OCT and radiographic images were scored separately. The gold standard was histopathological diagnosis from the serial sections. Cohen’s Kappa, sensitivity, negative predictive value and positive predictive value were computed for all measures. Results After 90 mins training, pre-standardized dentists were able to detect tooth decay more accurately using OCT than with visual or radiographic examination. Detection using OCT was somewhat better prior to sealant placement than afterwards. This effect varied in size depending on the type of sealant used. Radiographic diagnosis was also less accurate after sealant placement. Of the four dental sealants, Delton provided excellent positive predictive value and the best post-sealant negative predictive values. Conclusion In this ex vivo study, dentists were able to detect tooth decay beneath four commonly

  14. Patching for corneal abrasion.

    PubMed

    Lim, Chris H L; Turner, Angus; Lim, Blanche X

    2016-07-26

    Published audits have demonstrated that corneal abrasions are a common presenting eye complaint. Eye patches are often recommended for treating corneal abrasions despite the lack of evidence for their use. This systematic review was conducted to determine the effects of the eye patch when used to treat corneal abrasions. The objective of this review was to assess the effects of patching for corneal abrasion on healing and pain relief. We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 4), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to May 2016), EMBASE (January 1980 to May 2016), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to May 2016), System for Information on Grey Literature in Europe (OpenGrey) (January 1995 to May 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 9 May 2016. We also searched the reference lists of included studies, unpublished 'grey' literature and conference proceedings and contacted pharmaceutical companies for details of unpublished trials. We included randomised and quasi-randomised controlled trials that compared patching the eye with no patching to treat simple corneal abrasions. Two authors independently assessed the risk of bias and extracted data. Investigators were contacted for further information regarding the quality of trials. The primary outcome was healing at 24, 48 and 72 hours while secondary outcomes included measures of pain, quality of life and adverse effects. We graded the certainty of the evidence using GRADE. We included 12 trials which

  15. Characterization of the biological effect of fish fibrin glue in experiments on rats: Immunological and coagulation studies

    PubMed Central

    Laidmäe, Ivo; Salum, Tiit; Sawyer, Evelyn S.; Janmey, Paul A.; Uibo, Raivo

    2011-01-01

    Fibrin glues (FG) of human or bovine origin are widely used for haemostasis and wound healing. In addition FGs are studied in many biomedical areas like cell therapy or tissue engineering. As any mammalian plasma products FG-s pose risk of transmission of bacteria, viruses, or prions and may compromise patient homeostasis. In this study, we examined coagulation parameters and immunological status of rats treated with salmon-derived FG. We evaluated the changes in thrombin time, prothrombin activity, and presence of antibodies on 46 Wistar rats. This study shows that salmon-derived FG, injected intraperitoneally, does not cause coagulation disturbances in the peripheral blood. After a first challenge with salmon-derived FG there were low but detectable amounts of antibodies revealed by ELISA and immunoblot. After a second administration there was substantial elevation of antibodies to FG components and other copurifying plasma proteins. Antibody reactivity to human Factor Va, revealed in three animals, was not associated with FG application. Taken together, blood immunological and coagulation parameters support the suitability of salmon-derived FG in the development of fibrin sealants for medical use. PMID:19484773

  16. Near-IR imaging of demineralization under sealants

    NASA Astrophysics Data System (ADS)

    Tom, Henry; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    Previous studies have shown that near-IR reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum near-IR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study. Images before and after application of sealants were acquired using near-IR reflectance and near-IR transillumination at wavelengths of 1300 nm, 1460 nm, and 1500 - 1700 nm. Images were also acquired using polarization sensitive optical coherence tomography for comparison. The highest contrast for near- IR reflectance was at 1460 nm and 1500 - 1700 nm. These near-IR wavelengths are coincident with higher water absorption. The clear Delton sealant investigated was not visible in either co-polarization or crosspolarization OCT images. The wavelength region between 1500-1700-nm yielded the highest contrast of lesions under sealants for near-IR reflectance measurements.

  17. HVAC; Heating, Ventilation, Air Conditioning - Aerosol Duct Sealant

    DTIC Science & Technology

    2016-09-01

    designed before the duct sealant can begin. Any system deficiencies must be corrected. User findings/comments EXWC contacted Steven Wagner at...NAVAIR base. The technology did not require any maintenance and therefore there are no additional costs due to malfunctions. Steven Wagner reports that

  18. Evaluating cyclic fatigue of sealants during outdoor testing

    Treesearch

    R. Sam Williams; Steven Lacher; Corey Halpin; Christopher White

    2009-01-01

    A computer-controlled test apparatus (CCTA) and other instrumentation for subjecting sealant specimens to cyclic fatigue during outdoor exposure was developed. The CCTA enables us to use weather-induced conditions to cyclic fatigue specimens and to conduct controlled tests in-situ during the outdoor exposure. Thermally induced dimensional changes of an aluminum bar...

  19. Dental Pit and Fissure Sealants: Implications for School Health Personnel.

    ERIC Educational Resources Information Center

    McCormack-Brown, K. R.; And Others

    1989-01-01

    To promote good personal hygiene practices in students, school health personnel must be informed about dental pit and fissure sealants and related programs. Adoption and maintenance of such programs may depend on the success of school health personnel in educating administrators and policymakers. (SM)

  20. Dental Pit and Fissure Sealants: Implications for School Health Personnel.

    ERIC Educational Resources Information Center

    McCormack-Brown, K. R.; And Others

    1989-01-01

    To promote good personal hygiene practices in students, school health personnel must be informed about dental pit and fissure sealants and related programs. Adoption and maintenance of such programs may depend on the success of school health personnel in educating administrators and policymakers. (SM)

  1. Near-IR imaging of demineralization under sealants.

    PubMed

    Tom, Henry; Chan, Kenneth H; Darling, Cynthia L; Fried, Daniel

    2014-02-18

    Previous studies have shown that near-IR reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum near-IR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study. Images before and after application of sealants were acquired using near-IR reflectance and near-IR transillumination at wavelengths of 1300 nm, 1460 nm, and 1500 - 1700 nm. Images were also acquired using polarization sensitive optical coherence tomography for comparison. The highest contrast for near-IR reflectance was at 1460 nm and 1500 - 1700 nm. These near-IR wavelengths are coincident with higher water absorption. The clear Delton sealant investigated was not visible in either co-polarization or cross-polarization OCT images. The wavelength region between 1500-1700-nm yielded the highest contrast of lesions under sealants for near-IR reflectance measurements.

  2. The Safe Application of a New Lubricant Sealant,

    DTIC Science & Technology

    US-1 lubricant sealant is prepared which consists of an epoxy resin, a congealer (vat residue of hexamethylenediamine ), and a filler. The epoxy...resins have chemical stability, high adhesion, and anticorrosive and dielectric properties, but these resins and hexamethylenediamine are toxic. During

  3. A simple device for measuring adhesive failure in sealant joints

    SciTech Connect

    Shephard, N.E.; Wightman, J.P.

    1998-12-31

    The adhesion performance of a sealant is often assessed by conducting a peel adhesion test using the 180{degree} peel test, ASTM C 794-80 adhesion in peel. The ASTM C 784-80 test method is difficult to interpret for the following reasons: (2) only one peel speed is used to measure peel force, (2) the failure mode is predominately cohesive and (3) the peeling energy is dominated by the viscoelastic properties of the joint. Consequently, the 180{degree} peel test is not an optimal peel test for surface sensitive measurement. A 45{degree} peel test devise is described and compared to the 180{degree} peel test. The 45{degree} peel test measures the peeling speed as a function of applied fracture energy. Peel speed is measured using a displacement transducer. The applied fracture energy is provided by a known mass and the force of gravity. The peeling measurement is conducted at very slow peeling speeds, less than 10{sup 7} m/s in order to reduce the effect of viscose dissipation. Using model sealant formulations, the authors demonstrate the ability of the 45{degree} peel test to distinguish between the two sealant formulations. Conversely, the 180{degree} peel test is unable to measure a difference in adhesion between the two different sealants.

  4. Identification of VLDLR as a novel endothelial cell receptor for fibrin that modulates fibrin-dependent transendothelial migration of leukocytes.

    PubMed

    Yakovlev, Sergiy; Mikhailenko, Irina; Cao, Chunzhang; Zhang, Li; Strickland, Dudley K; Medved, Leonid

    2012-01-12

    While testing the effect of the (β15-66)(2) fragment, which mimics a pair of fibrin βN-domains, on the morphology of endothelial cells, we found that this fragment induces redistribution of vascular endothelial-cadherin in a process that is inhibited by the receptor-associated protein (RAP). Based on this finding, we hypothesized that fibrin may interact with members of RAP-dependent low-density lipoprotein (LDL) receptor family. To test this hypothesis, we examined the interaction of (β15-66)(2), fibrin, and several fibrin-derived fragments with 2 members of this family by ELISA and surface plasmon resonance. The experiments showed that very LDL (VLDL) receptor (VLDLR) interacts with high affinity with fibrin through its βN-domains, and this interaction is inhibited by RAP and (β15-66)(2). Furthermore, RAP inhibited transendothelial migration of neutrophils induced by fibrin-derived NDSK-II fragment containing βN-domains, suggesting the involvement of VLDLR in fibrin-dependent leukocyte transmigration. Our experiments with VLDLR-deficient mice confirmed this suggestion by showing that, in contrast to wild-type mice, fibrin-dependent leukocyte transmigration does not occur in such mice. Altogether, the present study identified VLDLR as a novel endothelial cell receptor for fibrin that promotes fibrin-dependent leukocyte transmigration and thereby inflammation. Establishing the molecular mechanism underlying this interaction may result in the development of novel inhibitors of fibrin-dependent inflammation.

  5. The calcification of fibrin in vitro

    NASA Astrophysics Data System (ADS)

    Koutsopoulos, S.; Dalas, E.

    2000-06-01

    In the present work we employed fibrin in order to assess its capability to induce biological mineralization. Fibrin is a very important factor in the blood-clotting system. Structurally, fibrin is an ordered organic matrix which has a periodic structure that repeats every 230 Å. Hydroxyapatite, HAP and octacalcium phosphate (OCP) are the most interesting calcium phosphate salts. Hydroxyapatite is thermodynamically the most stable calcium phosphate which is mostly used as a model compound for the study of biological-calcification processes. On the other hand, octacalcium phosphate has been proposed as a precursor of hydroxyapatite whose formation is favoured kinetically in solutions supersaturated to both salts. The kinetics of crystallization of HAP and OCP on fibrin were studied using the constant composition technique. The onset of HAP crystallization started immediately after introducing the substrate in the supersaturated solution. Unlike HAP crystallization induction periods were observed before the appearance of OCP precipitate in a solution supersaturated with respect to both HAP and OCP. Using nucleation rate equations derived from the classical homogeneous nucleation theory, interfacial energies and the size of the critical nucleus for both HAP and OCP were calculated. Phosphate was taken up extensively by the biological molecule studied. The dependence of adsorption upon ionic strength and pH of the medium suggests an appreciable contribution of electrostatic forces. Controversially calcium ions did not exhibit any detectable adsorption from solutions containing calcium dichloride at concentrations ranging from 1×10 -4 to 5×10 -3 M in 0.15 M NaCl supporting electrolyte, 37°C, pH=7.4. From the results above it follows that formation of HAP on fibrin may be initiated via adsorption of inorganic phosphate on the biological substrate.

  6. Long-term performance of resin based fissure sealants placed in a general dental practice.

    PubMed

    Hevinga, M A; Opdam, N J M; Bronkhorst, E M; Truin, G J; Huysmans, M C D N J M

    2010-01-01

    The aim of the present retrospective study was to evaluate the long-term performance of resin based fissure sealants applied in a general dental practice. Regularly attending patients visiting the practice between July 2006 until November 2007 and who had received sealants before 1st of January 2000 were included in the study. Date of placement of a sealant in posterior non-discoloured permanent teeth and replacement by a restoration was recorded. In a clinical examination occlusal surfaces were scored for (partial) sealant loss and fissure discolouration. The restoration profile of the patient was assessed as low or high, based on the number of restorations placed per year since the first sealant. Sealants had been applied by four dentists and a dental hygienist. 1204 sealants were placed in 148 patients. After a mean follow-up time of 11.6 years, 41.3% of placed sealants were still fully retained and 11.4% were replaced by a restoration. Failure rates were significantly higher in high than in low restoration profile patients and in molars compared to premolars. In those fissures with lost or partially lost sealants, discolouration frequently occurred (40% of all surfaces) irrespective of restoration profile of the patient. In this retrospective practice based study, long-term performance of sealants depended on restoration profile of the individual patient and the tooth type (molar versus premolar).

  7. Bond strength of Bis-GMA and glass ionomer pit and fissure sealants using cyclic fatigue.

    PubMed

    Dewji, H R; Drummond, J L; Fadavi, S; Punwani, I

    1998-02-01

    The aim of the study was to determine the bond strength of glass ionomer and resin-modified glass ionomer sealants compared to Bis-GMA sealants using both static and cyclic fatigue shear testing. Four materials were evaluated: D, a Bis-GMA sealant with 10% phosphoric acid etchant; FC, a resin-modified glass ionomer sealant with 20% polyacrylic acid etchant; FD, a resin-modified glass ionomer sealant with 10% polyacrylic acid etchant; and FSC, a self-cured glass ionomer sealant with no etchant. Gelatin capsules filled with the sealant material were bonded to the enamel surfaces of bovine teeth after appropriate surface conditioning and then tested in shear static and cyclic fatigue. Static and cyclic shear bond strengths, respectively, for each group were (MPa): FC: 21.1+/-2.8 and 17.1+/-3.1; FD: 14.6+/-5.9 and 8.5+/-3.1; D: 10.8+/-4.9 and 4.7+/-2.6; FSC: 8.7 (1.0 and 2.9+/-0.6. The resin-modified glass ionomer sealants had better fatigue bond strength than both Bis-GMA and self-cured glass ionomer sealants with the surface conditioning affecting the bond strength of the resin-modified glass ionomer sealants.

  8. Effect of Fluoridated Sealants on Adjacent Tooth Surfaces

    PubMed Central

    Cagetti, M.G.; Carta, G.; Cocco, F.; Sale, S.; Congiu, G.; Mura, A.; Strohmenger, L.; Lingström, P.; Campus, G.

    2014-01-01

    A double-blind randomized clinical trial was performed in 6- to 7-yr-old schoolchildren to evaluate, in a 30-mo period, whether the caries increment on the distal surface of the second primary molars adjacent to permanent first molars sealed with fluoride release compounds would be lower with respect to those adjacent to permanent first molars sealed with a nonfluoridated sealant. In sum, 2,776 subjects were enrolled and randomly divided into 3 groups receiving sealants on sound first molars: high-viscosity glass ionomer cement (GIC group); resin-based sealant with fluoride (fluoride-RB group); and a resin-based sealant without fluoride (RB group). Caries (D1 – D3 level) was recorded on the distal surface of the second primary molar, considered the unit of analysis including only sound surfaces at the baseline. At baseline, no differences in caries prevalence were recorded in the 3 groups regarding the considered surfaces. At follow-up, the prevalence of an affected unit of analysis was statistically lower (p = .03) in the GIC and fluoride-RB groups (p = .04). In the GIC group, fewer new caries were observed in the unit of analysis respect to the other 2 groups. Incidence rate ratios (IRRs) were 0.70 (95% confidence interval: 0.50, 0.68; p < .01) for GIC vs. RB and 0.79 (95% confidence interval: 0.53, 1.04; p = .005) for fluoride-RB vs. RB. Caries incidence was significantly associated with low socioeconomic status (IRR = 1.18; 95% confidence interval: 1.10, 1.42; p = .05). Dental sealant high-viscosity GIC and fluoride-RB demonstrated protection against dental caries, and there was evidence that these materials afforded additional protection for the tooth nearest to the sealed tooth (clinical trial registration NCT01588210). PMID:24846910

  9. Bright Patches on Ariel

    NASA Image and Video Library

    1998-12-05

    Distinct bright patches are visible on Ariel, the brightest of Uranus five largest satellites. NASA Voyager 2 obtained this image Jan. 22, 1986, from a distance of 2.52 million kilometers 1.56 million miles.

  10. Gemini 6 patch

    NASA Image and Video Library

    1965-01-01

    The Gemini 6 patch is hexagonal in shape, reflecting the mission number; and the spacecraft trajectory also traces out the number "6". The Gemini 6 spacecraft is shown superimposed on the "twin stars" Castor and Pollux, for "Gemini".

  11. Lidocaine Transdermal Patch

    MedlinePlus

    Lidocaine patches are used to relieve the pain of post-herpetic neuralgia (PHN; the burning, stabbing pains, ... for months or years after a shingles infection). Lidocaine is in a class of medications called local ...

  12. Rotigotine Transdermal Patch

    MedlinePlus

    ... that causes difficulties with movement, muscle control, and balance) including shaking of parts of the body, stiffness, slowed movements, and problems with balance. Rotigotine transdermal patches are also used to treat ...

  13. Glass ionomer ART sealants in Chinese school children-6-year results.

    PubMed

    Holmgren, Christopher J; Lo, Edward C M; Hu, Deyu

    2013-09-01

    To evaluate longitudinally ART sealants placed in Chinese school children under field conditions. 191 ART sealants were placed in 140 children, aged 11-14 years, by five assistant dentists in four secondary schools in Deyang, Sichuan Province, China. Teeth selected for sealing were those with pits and fissures that were deep or showing early enamel caries. Teeth were excluded if there was obvious cavitation extending into dentine. Standard instruments and procedures for ART sealants were used. The material used was a high-viscosity glass-ionomer (Ketac-Molar, 3MESPE) that was inserted into the pits and fissures with the "press-finger" technique. The status of the sealants was evaluated annually over 6 years after placement by the same examiner who was not involved in the placement of the sealants using explorers, mouth-mirrors and an intra-oral fibre-optic light. No missing sealants were replaced during the study. 107 sealants (56% of the original) were examined after 6 years. The cumulative survival rates of the sealants (partially or fully retained) after 2, 4 and 6 years were 79%, 68% and 59%, respectively. Caries prevention lagged the fall in sealant survival but remained high throughout the study period, being over 90% in the first 4 years and 85% after 6 years. ART sealants placed under field conditions in Chinese schoolchildren have a high retention rate. Missing sealants should be replaced to maintain their preventive efficacy. The sealing of pits and fissures can be an effective caries preventive approach. Resin-based sealants have the disadvantage in that they require an optimal level of moisture control during placement. In children and in outreach situations glass ionomer ART sealants, which are more moisture tolerant, can offer a viable alternative. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. FNAL system patching design

    SciTech Connect

    Schmidt, Jack; Lilianstrom, Al; Romero, Andy; Dawson, Troy; Sieh, Connie; /Fermilab

    2004-01-01

    FNAL has over 5000 PCs running either Linux or Windows software. Protecting these systems efficiently against the latest vulnerabilities that arise has prompted FNAL to take a more central approach to patching systems. Due to different levels of existing support infrastructures, the patching solution for linux systems differs from that of windows systems. In either case, systems are checked for vulnerabilities by Computer Security using the Nessus tool.

  15. Interactions between F-111 Fuselage Fuel Tank Sealants. Part I. Characterisation of Polyester Sealants and their Hydrolytic Degradation Products,

    DTIC Science & Technology

    1983-12-01

    maleic acid , adipic acid , azelaic acid and suberic acid . To ensure complete esterification during the exhaustive degradation reactions, an...spectroscopic techniques. Major components were shown to be sebacic acid and neopentyl glycol. The most significant difference between the two polyester...and acid equivalent weights of the prepolymers, their hydrolysis products and hydrolysed cured sealants were determined to assess extent of degradation

  16. Evaluation of Different Fissure Sealant Materials and Flowable Composites Used as Pit-and-fissure Sealants: A 24-Month Clinical Trial.

    PubMed

    Kucukyilmaz, Ebru; Savas, Selcuk

    2015-01-01

    The effectiveness of resin-based pit-and-fissure sealants mainly depends on their retention and integrity over time. The purpose of this study was to evaluate retention rates of two different pit-and-fissure sealants compared with a flowable composite and a self-adhesive flowable composite over a 24 month period. A split-mouth study design was used for all four permanent first molars of each patient. They were subjected to different kinds of sealants--either flowable composites or with fissure sealants. The flowable composites used were: flowable composite with an adhesive system (Tetric EvoFlow); and a self-adhesive flowable composite (Vertise Flow). The fissure sealants used were: a highly filled pit-and-fissure sealant (Fissurit FX); and a highly filled nano-hybrid pit-and-fissure sealant (Grandio Seal). Evaluation of the sealants was carried out at three-, six-, 12-, 18-, and 24-month follow-up visits. The complete retention rates were 95.7 percent for Tetric EvoFlow, 80.6 percent for Fissurit FX, 73.1 percent for Grandio Seal, and 62.9 percent for Vertise Flow. The retention rate of Tetric EvoFlow was significantly higher among all materials tested (P<0.05). The flowable composite used with an adhesive system was found to be superior to other sealing materials.

  17. Occlusal sealant success over ten years in a private practice: comparing longevity of sealants placed by dentists, hygienists, and assistants.

    PubMed

    Folke, Bernadette D; Walton, James L; Feigal, Robert J

    2004-01-01

    The purpose of this 10-year, retrospective, cohort study was to evaluate the success of permanent molar sealants by comparing the effectiveness of sealants placed by dentists, dental hygienists, and dental assistants in a private dental practice, with all operators using an identical, standardized, application technique and 4-handed dentistry. From 810 patient records that met entry criteria, the long-term follow-up records of 3,194 permanent first molars were evaluated. Data were collected and evaluated by survival analyses methods for: (1) time to first failure (caries or restoration of the sealed surface); (2) fluoride history; (3) caries experience; (4) operator type; (5) behavior at sealant placement; (6) tooth type; (7) age at placement; and (8) patient gender. Cumulative survival probability for 10 years in this practice was 87%, using Kaplan Meier analyses. The factors associated with an increased risk of failure included: (1) age (P<.001); (2) dmft (P<.003); (3) no fluoride (P<.001); (4) dentist (P<.001); and (5) registered dental assistant (P<.001). While all operator groups had success rates equal to or exceeding previous studies, dentists and registered dental assistants showed 3 times and 2 times the risk of failure, respectively, compared to the registered dental hygienists. The no-fluoride group showed almost twice the risk of failure as compared to the optimal fluoride group. Behavior showed a slightly higher risk of failure that approached significance. Age and dmft were highly significant, with slight increased risk of failure. Supplemental fluoride showed a protective effect, but this was marginally significant. Gender and tooth-type were not significant in this model. Major variations in success rates were observed in the dental assistant group, with 2 individuals accounting for most of the failures. This study supports delegation of sealant delivery to auxiliaries, since dental assistants and dental hygienists were equal to or better than the

  18. Preparation of hybrid scaffold from fibrin and biodegradable polymer fiber.

    PubMed

    Hokugo, Akishige; Takamoto, Tomoaki; Tabata, Yasuhiko

    2006-01-01

    A biodegradable hybrid scaffold was prepared from fibrin and poly(glycolic acid) (PGA) fiber. Mixed fibrinogen and thrombin solution homogeneously dispersed in the presence of various amounts (0, 1.5, 3.0, and 6.0mg) of PGA fiber was freeze-dried to obtain fibrin sponges with or without PGA fiber incorporation. By scanning electron microscopy observation, the fibrin sponges had an interconnected pore structure, irrespective of the amount of PGA fiber incorporated. PGA fiber incorporation enabled the fibrin sponges to significantly enhance their compression strength. In vitro cell culture studies revealed that the number of L929 fibroblasts initially attached was significantly larger for any fibrin sponge with PGA fiber incorporation than for the fibrin sponge without PGA fiber. The shrinkage of sponges after cell seeding was suppressed by fiber incorporation. It is possible that the shrinkage suppression of sponges maintains their intraspace, resulting in the superior cell attachment of a sponge with PGA fiber incorporation. After subcutaneous implantation into the backs of mice, the residual volume of a fibrin sponge with PGA fiber incorporation was significant compared with that of a fibrin sponge without PGA fiber. Larger number of cells infiltrated deep inside the fibrin sponges with PGA fiber incorporation implanted subcutaneously. It is concluded that the fibrin sponge reinforced by fiber incorporation is a promising three-dimensional scaffold of cells for tissue engineering.

  19. Chitosan whiskers from shrimp shells incorporated into dimethacrylate-based dental resin sealant.

    PubMed

    Mahapoka, Ekamon; Arirachakaran, Pratanporn; Watthanaphanit, Anyarat; Rujiravanit, Ratana; Poolthong, Suchit

    2012-01-01

    A resin-based sealant containing chitosan whiskers was developed for use as a pit and fissure sealer. Chitosan whiskers were synthesized and then characterized using Fourier transform infrared spectrometry and transmission electron microscopy. The whiskers were next incorporated into dimethacrylate monomer at various ratios by weight and subsequently analyzed for their antimicrobial and physical properties. The dimethacrylate-based sealant containing chitosan whiskers had a greater antimicrobial activity than control sealant and they were comparable with antimicrobial commercial resin sealants. The inclusion of the whiskers did not reduce the curing depth or degree of double bond conversion and the reduction in hardness was minimal. In conclusion, a resin-based sealant containing chitosan whiskers can be considered an effective antimicrobial pit and fissure sealant.

  20. Gel Permeation Chromatography Analysis of Coal Tar-Based Joint Sealants

    DTIC Science & Technology

    1994-06-01

    brittle. Objective The objective of this research was to determine if a laboratory test method could be used to identify joint sealant materials that... test method to determine the effects of prolonged heating and aging in sealants. Chapter 2 Laboratory Teat Plan 9 3 Phase I and II - Presentation and... method used to track materials that have been received for testing . The FPL number will be used to represent the different sealants instead of using prod

  1. Monitoring Sealant Durability during Instrumented Outdoor Exposure with Variation in Prestrain

    Treesearch

    Gregory T. Schueneman; Steven Lacher; Christopher G. Hunt

    2015-01-01

    Sealants are a vital part of a building’s environmental barrier envelope. Their ability to bond to numerous dissimilar substrates and form cure-in-place seals results in their widespread use throughout single story and high rise buildings. A typical 40 story concrete and glass facade building can have 70 miles of sealant bonds. Failure of sealants can lead to energy...

  2. Sperm Patch-Clamp

    PubMed Central

    Lishko, Polina; Clapham, David E.; Navarro, Betsy; Kirichok, Yuriy

    2014-01-01

    Sperm intracellular pH and calcium concentration ([Ca2+]i) are two central factors that control sperm activity within the female reproductive tract. As such, the ion channels of the sperm plasma membrane that alter intracellular sperm [Ca2+] and pH play important roles in sperm physiology and the process of fertilization. Indeed, sperm ion channels regulate sperm motility, control sperm chemotaxis toward the egg in some species, and may trigger the acrosome reaction. Until recently, our understanding of these important molecules was rudimentary due to the inability to patch-clamp spermatozoa and directly record the activity of these ion channels under voltage clamp. Recently, we overcame this technical barrier and developed a method for reproducible application of the patch-clamp technique to mouse and human spermatozoa. This chapter covers important aspects of application of the patch-clamp technique to spermatozoa, such as selection of the electrophysiological equipment, isolation of spermatozoa for patch-clamp experiments, formation of the gigaohm seal with spermatozoa, and transition into the whole-cell mode of recording. We also discuss potential pitfalls in application of the patch-clamp technique to flagellar ion channels. PMID:23522465

  3. Pressure wall patch

    NASA Technical Reports Server (NTRS)

    Williamsen, Joel E. (Inventor); Weddendorf, Bruce C. (Inventor)

    1994-01-01

    A rigid patch body for placing over a damaged portion (hole) of an external wall of a pressurized vessel, such as a space vehicle or a habitat, is discussed. The rigid patch body allows an astronaut to make temporary repairs to the pressurized vessel from the exterior of the vessel, which enables more permanent repairs to be made from the interior of the vessel. The pressure wall patch of the present invention includes a floor surrounded by four side members. Each side member includes a threaded screw for anchoring the patch body to the external wall of the pressurized vessel and a recess in its lower surface for supporting an inflatable bladder for surrounding the damaged portion (hole) of the external wall to seal the area surrounding the damaged portion. This allows the vessel to be repressurized. The floor of the rigid patch body supports a source of gas that is connected to the gas supply valve and a gas supply gauge in communication with the gas supply valve and the inflatable bladder.

  4. Toward an understanding of fibrin branching structure

    NASA Astrophysics Data System (ADS)

    Fogelson, Aaron L.; Keener, James P.

    2010-05-01

    The blood clotting enzyme thrombin converts fibrinogen molecules into fibrin monomers which polymerize to form a fibrous three-dimensional gel. The concentration of thrombin affects the architecture of the resulting gel, in particular, a higher concentration of thrombin produces a gel with more branch points per unit volume and with shorter fiber segments between branch points. We propose a mechanism by which fibrin branching can occur and show that this mechanism can lead to dependence of the gel’s structure (at the time of gelation) on the rate at which monomer is supplied. A higher rate of monomer supply leads to a gel with a higher branch concentration and with shorter fiber segments between branch points. The origin of this dependence is explained.

  5. Toward an understanding of fibrin branching structure.

    PubMed

    Fogelson, Aaron L; Keener, James P

    2010-05-01

    The blood clotting enzyme thrombin converts fibrinogen molecules into fibrin monomers which polymerize to form a fibrous three-dimensional gel. The concentration of thrombin affects the architecture of the resulting gel, in particular, a higher concentration of thrombin produces a gel with more branch points per unit volume and with shorter fiber segments between branch points. We propose a mechanism by which fibrin branching can occur and show that this mechanism can lead to dependence of the gel's structure (at the time of gelation) on the rate at which monomer is supplied. A higher rate of monomer supply leads to a gel with a higher branch concentration and with shorter fiber segments between branch points. The origin of this dependence is explained.

  6. Long-term functional benefits of human embryonic stem cell-derived cardiac progenitors embedded into a fibrin scaffold.

    PubMed

    Bellamy, Valérie; Vanneaux, Valérie; Bel, Alain; Nemetalla, Hany; Emmanuelle Boitard, Solène; Farouz, Yohan; Joanne, Pierre; Perier, Marie-Cécile; Robidel, Estelle; Mandet, Chantal; Hagège, Albert; Bruneval, Patrick; Larghero, Jérôme; Agbulut, Onnik; Menasché, Philippe

    2015-09-01

    Cardiac-committed cells and biomimetic scaffolds independently improve the therapeutic efficacy of stem cells. In this study we tested the long-term effects of their combination. Eighty immune-deficient rats underwent permanent coronary artery ligation. Five to 7 weeks later, those with an echocardiographically measured ejection fraction (EF) ≤55% were re-operated on and randomly allocated to receive a cell-free fibrin patch (n = 25), a fibrin patch loaded with 700,000 human embryonic stem cells (ESC) pre-treated to promote early cardiac differentiation (SSEA-1(+) progenitors [n = 30]), or to serve as sham-operated animals (n = 25). Left ventricular function was assessed by echocardiography at baseline and every month thereafter until 4 months. Hearts were then processed for assessment of fibrosis and angiogenesis and a 5-component heart failure score was constructed by integrating the absolute change in left ventricular end-systolic volume (LVESV) between 4 months and baseline, and the quantitative polymerase chain reaction (qPCR)-based expression of natriuretic peptides A and B, myosin heavy chain 7 and periostin. All data were recorded and analyzed in a blinded manner. The cell-treated group consistently yielded better functional outcomes than the sham-operated group (p = 0.002 for EF; p = 0.01 for LVESV). Angiogenesis in the border zone was also significantly greater in the cell-fibrin group (p = 0.006), which yielded the lowest heart failure score (p = 0.04 vs sham). Engrafted progenitors were only detected shortly after transplantation; no grafted cells were identified after 4 months. There was no teratoma identified. A fibrin scaffold loaded with ESC-derived cardiac progenitors resulted in sustained improvement in contractility and attenuation of remodeling without sustained donor cell engraftment. A paracrine effect, possibly on innate reparative responses, is a possible mechanism for this enduring effect. Copyright © 2015 International Society for Heart

  7. Isolite vs cotton roll isolation in the placement of dental sealants.

    PubMed

    Lyman, Todd; Viswanathan, Kavitha; McWhorter, Alton

    2013-01-01

    The purpose of this split-mouth, randomized, controlled trial was to evaluate the retention rates of sealants placed under Isolite vs cotton roll isolation. A convenience sample of 29 patients, with a mean age of 9.8 years and a total of 96 teeth, was included in this study. Matched contralateral pairs of first and second molars were randomized to receive sealants with Isolite or cotton roll isolation. All sealants were performed by one standardized operator. Sealants were placed on first and second permanent molars that had a matched contralateral molar requiring a sealant as well. Photographs were taken of the sealants on the day of placement, and at 6-month and 12-month recalls. Photographs were viewed, and retention of the sealants was evaluated and scored by three calibrated pediatric dentists. The scores were analyzed via Mann-Whitney U and chi-square tests. There were no significant differences in the retention rates between sealants placed using Isolite isolation compared with cotton roll isolation. Isolite and cotton roll isolation both appear to be equally effective in creating a favorable environment for sealant placement by a single operator.

  8. The effects of opaque and clear pit and fissure sealants on infrared laser fluorescence measurements.

    PubMed

    Bahrololoomi, Z; Khodabakhsh, M; Khaksar, Y

    2014-06-01

    The purpose of placing sealants is to inhibit caries by physical closure of the pits and fissures of teeth. A device named DIAGNOdent is useful in detecting occlusal caries by employing laser fluorescence (LF). However, there are contradictory results in the influence of sealants on LF measurements. The aim of this study is to investigate the effects of two different types of fissure sealants on LF measurements. In this in vitro study, 86 extracted permanent third molars were divided randomly into two groups and clear or opaque sealant was applied on the occlusal surfaces. Two examiners performed pre- and post-seal fluorescence measurements twice with one week interval by employing DIAGNOdent device. Finally, measured values were evaluated through the statistical paired t-test by means of SPSS 17 software. The mean value of LF measurements increased significantly due to the application of clear sealant (p= 0.001) while the statistical changes in this measurement was negligible after applying opaque sealant (p= 0.311). Clear sealants increase the LF measured values but opaque sealants cause almost no changes. Therefore, DIAGNOdent device is not reliable for detecting caries beneath the clear sealant.

  9. Effects of the preparation technique and type of material on the penetrability of sealants.

    PubMed

    Cho, John S; Covey, David; Abdelmegid, Faika; Salama, Fouad

    2015-01-01

    The purpose of this in vitro study was to compare the penetration of 2 resin-based and 2 glass ionomer sealants into fissures after either conventional or mechanical preparation. All the materials placed in the conventionally prepared and mechanically prepared fissures penetrated the fissures beyond the standard (0.5-mm) reference line used in this study. For 1 glass ionomer sealant, the number of specimens showing complete penetration of sealant was significantly greater (P < 0.05) in mechanically prepared fissures than in conventionally prepared ones. No significant differences were found between mechanically and conventionally prepared fissures for the other sealants.

  10. The Effects of Opaque and Clear Pit and Fissure Sealants on Infrared Laser Fluorescence Measurements

    PubMed Central

    Bahrololoomi, Z.; Khodabakhsh, M.; Khaksar, Y.

    2014-01-01

    Statement of the Problem: The purpose of placing sealants is to inhibit caries by physical closure of the pits and fissures of teeth. A device named DIAGNOdent is useful in detecting occlusal caries by employing laser fluorescence (LF). However, there are contradictory results in the influence of sealants on LF measurements. Purpose: The aim of this study is to investigate the effects of two different types of fissure sealants on LF measurements. Materials and Method: In this in vitro study, 86 extracted permanent third molars were divided randomly into two groups and clear or opaque sealant was applied on the occlusal surfaces. Two examiners performed pre- and post-seal fluorescence measurements twice with one week interval by employing DIAGNOdent device. Finally, measured values were evaluated through the statistical paired t-test by means of SPSS 17 software. Results: The mean value of LF measurements increased significantly due to the application of clear sealant (p= 0.001) while the statistical changes in this measurement was negligible after applying opaque sealant (p= 0.311). Conclusion: Clear sealants increase the LF measured values but opaque sealants cause almost no changes. Therefore, DIAGNOdent device is not reliable for detecting caries beneath the clear sealant. PMID:24883342

  11. Development of 400 F sealants for flat plate solar collector construction and installation

    NASA Astrophysics Data System (ADS)

    Morris, L.; Schubert, R. J.

    1980-03-01

    Twenty candidate sealants representing ten different polymer types were evaluated as potential solar collector sealants. Polymer types tested included epichlorohydrin rubber, EPDM rubber, silicone, polysulfide, acrylate rubber, and a fluoroelastomer. Initial screening of sealants consisted of measuring high temperature stability and adhesion retention. Several sealant compositions exhibited satisfactory performance in these tests and were selected for further evaluation. These materials were based on an EPDM rubber, a Viton fluoroelastomer, and silicone polymers. Further testing of these candidate materials included determination of adhesion retention under uv/water/heat conditions, fogging temperature, low temperature flexibility, and physical properties. Four silicone-based materials appeared to be suitable candidates for sealing solar collectors.

  12. Toxicity of coal-tar and asphalt sealants to eastern newts, Notophthalmus viridescens.

    PubMed

    Bommarito, Thomas; Sparling, Donald W; Halbrook, Richard S

    2010-09-01

    Between 1970 and 2000 the concentration of total polycyclic aromatic hydrocarbons (TPAH) in several lakes across the country increased whereas those of other persistent organic pollutants (POPs) tended to remain stable or declined. Urbanized watersheds experienced greater rises in TPAH concentration compared to non-urban lakes. Sources for urban PAHs include industrial wastes, vehicular exhausts and oil leaks and sealants from pavement surfaces. Both coal-tar and asphalt sealants are used to protect surfaces but runoff from surfaces coated with coal-tar can have mean concentrations of 3500 mg TPAHs kg(-1), much higher than runoff from asphalt-sealed or cement surfaces. Unaltered parent compounds of PAHs can have many lethal and sublethal toxic effects, but oxidation and UV radiation can alter the toxicity of these compounds, sometimes creating degradates that are many times more toxic than parent compounds. The purposes of this study were to determine if coal-tar sealants can be toxic to adult eastern newts (Notophthalmus viridescens) and to compare the toxicity of coal-tar sealant to that of asphalt sealant. Newts were exposed to sediments containing dried sealants ranging from 0 mg kg(-1) to 1500 mg kg(-1) under simultaneous exposure to UV radiation and visible light to determine concentration/response relationships. No significant mortality occurred with any treatment. Significant effects due to sealants included decreased righting ability and diminished liver enzyme activities. Coal-tar sealant was more effective in inducing these changes than was asphalt sealant.

  13. Ducts Sealing Using Injected Spray Sealant, Raleigh, North Carolina (Fact Sheet)

    SciTech Connect

    Not Available

    2014-03-01

    In multifamily and attached buildings, traditional duct sealing methods are often impractical or costly and disruptive because of the difficulty in accessing leakage sites. In this project, two retrofit duct sealing techniques - manually-applied sealants and injecting a spray sealant, were implemented in several low-rise multi-unit buildings. An analysis on the cost and performance of the two methods are presented. Each method was used in twenty housing units: approximately half of each group of units are single story and the remainder two-story. Results show that duct leakage to the outside was reduced by an average of 59% through the use of manual methods, and by 90% in the units where the injected spray sealant was used. It was found that 73% of the leakage reduction in homes that were treated with injected spray sealant was attributable to the manual sealing done at boots, returns and the air handler. The cost of manually-applying sealant ranged from $275 to $511 per unit and for the injected spray sealant the cost was $700 per unit. Modeling suggests a simple payback of 2.2 years for manual sealing and 4.7 years for the injected spray sealant system. Utility bills were collected for one year before and after the retrofits. Utility bill analysis shows 14% and 16% energy savings using injected spray sealant system and hand sealing procedure respectively in heating season whereas in cooling season, energy savings using injected spray sealant system and hand sealing were both 16%.

  14. Twenty-four month clinical evaluation of fissure sealants on partially erupted permanent first molars: glass ionomer versus resin-based sealant.

    PubMed

    Antonson, Sibel A; Antonson, Donald E; Brener, Sandra; Crutchfield, Jude; Larumbe, Jose; Michaud, Christie; Yazici, A Rüya; Hardigan, Patrick C; Alempour, Samira; Evans, David; Ocanto, Rome

    2012-02-01

    Glass ionomer sealants are an alternative to resin-based sealants, especially for use in partially erupted permanent molars. The authors conducted a study to compare the retention, marginal staining and cariostatic properties of a glass ionomer sealant with those of a resin-based sealant during a 24-month period. We included in this study 39 patients aged 5 through 9 years who had bilateral partially erupted first permanent molars. One of us (S.B.) placed a resin-based sealant (Delton Plus FS+, Dentsply Professional, York, Pa.) (group D) on a partially erupted first molar in one quadrant of the maxilla or mandible and a glass ionomer sealant (GC Fuji Triage White, GC America, Alsip, Ill.) (group T) in the other quadrant. Two masked and calibrated investigators (S.A.A., J.C.) evaluated the sealants for retention, marginal staining and carious lesions at three, six, 12 and 24 months. The authors used a multinomial regression for statistical analysis (P < .05). The recall rate was 69.2 percent at 24 months. Two sealants from group D and three from group T were lost completely. Complete retention rates at 24 months were 40.7 and 44.4 percent for groups D and T, respectively. The authors found no statistically significant difference in retention rates between groups at each recall examination (P > .05). For marginal staining, sealants in the resin-based group exhibited statistically higher marginal staining than did sealants in the glass ionomer group (P < .05). Although the authors detected no caries in teeth in group T, teeth in group D in which the sealant was lost completely experienced demineralization. Resin-based and glass ionomer sealants exhibited similar retention rates at 24 months. However, marginal staining was lower in the glass ionomer group, and the authors found no caries in teeth in this group. Consequently, glass ionomer sealants may be a better choice when salivary contamination is expected. Sealing during tooth eruption presents a particular

  15. Results of patch tests

    SciTech Connect

    Pontius, D.H.

    1994-10-01

    The objectives of this work were to construct, install, and operate a patch testing unit on a hot gas stream at a coal-fired fluidized-bed boiler. A 2,000-hour patch test was conducted on ceramic disks of materials used in the fabrication of ceramic candles and ceramic cross-flow filters. The primary issues addressed in these tests were the long-term physical, thermal, and chemical stability of the ceramic materials; long-term pressure drop and filtration characteristics of the ceramic filters; potential for irreversible blinding of filter elements; and long-term performance and reliability of auxiliary hardware, such as the tube sheet and pulse-cleaning systems. Results on three samples, or patches, 10 cm in diameter are given.

  16. Cost analysis of pulmonary lobectomy procedure: comparison of stapler versus precision dissection and sealant

    PubMed Central

    Droghetti, Andrea; Marulli, Giuseppe; Vannucci, Jacopo; Giovanardi, Michele; Bottoli, Maria Caterina; Ragusa, Mark; Muriana, Giovanni

    2017-01-01

    Objective We aimed to evaluate the direct costs of pulmonary lobectomy hospitalization, comparing surgical techniques for the division of interlobar fissures: stapler (ST) versus electrocautery and hemostatic sealant patch (ES). Methods The cost comparison analysis was based on the clinical pathway and drawn up by collecting the information available from the Thoracic Surgery Division medical team at Mantova Hospital. Direct resource consumption was derived from a previous randomized controlled trial including 40 patients. Use and maintenance of technology, equipment and operating room; administrative plus general costs; and 30-day use of postsurgery hospital resources were considered. The analysis was conducted from the hospital perspective. Results On the average, a patient submitted to pulmonary lobectomy costs €9,744.29. This sum could vary from €9,027 (using ES) to €10,460 (using ST). The overall lower incidence (50% vs 95%, P=0.0001) and duration of air leakage (1.7 days vs 4.5 days, P=0.0001) in the ES group significantly affects the mean time of hospital stay (11.0 days vs 14.3 days) and costs. Cost saving in the ES group was also driven by the lower incidence of complications. The main key cost driver was staff employment (42%), then consumables (34%) and operating room costs (12%). Conclusion There is an overall saving of around €1,432.90 when using ES patch for each pulmonary lobectomy. Among patients undergoing this surgical procedure, ES can significantly reduce air leakage incidence and duration, as well as decrease hospitalization rates. However, further multicenter research should be developed considering different clinical and managerial settings. PMID:28408847

  17. First impressions about Adherus, a new dural sealant.

    PubMed

    Zoia, Cesare; Bongetta, Daniele; Lombardi, Francesco; Custodi, Viola Marta; Pugliese, Raffaelino; Gaetani, Paolo

    2015-12-18

    The aim of the study is to report our first impressions about Adherus, a novel dural sealant, used in neurosurgical endoscopic transnasal procedures. We retrospectively reviewed the clinical and surgical records of the first 11 patients with intraoperative high-flow cerebrospinal fluid leak treated with the aid of Adherus at our center between February and October 2014. The healing at the level of the dural plasty was monitored and evaluated radiologically and with regular endoscopic inspections. With a median follow-up of 210 days, no postoperative CSF leak or surgical site infections were found in any of the cases. Based on our preliminary experience, this new dural sealant seems to provide an effective aid in dural plasty during endoscopic transphenoidal procedures.

  18. Studies of new perfluoroether elastomeric sealants. [for aircraft fuel tanks

    NASA Technical Reports Server (NTRS)

    Basiulis, D. I.; Salisbury, D. P.

    1981-01-01

    Channel and filleting sealants were developed successfully from cyano and diamidoxime terminated perfluoro alkylene ether prepolymers. The prepolymers were polymerized, formulated and tested. The polymers and/or formulations therefrom were evaluated as to their physical, mechanical and chemical properties (i.e., specific gravity, hardness, nonvolatile content, corrosion resistance, stress corrosion, pressure rupture resistance, low temperature flexibility, gap sealing efficiency, tensile strength and elongation, dynamic mechanical behavior, compression set, fuel resistance, thermal properties and processability). Other applications of the formulated polymrs and incorporation of the basic prepolymers into other polymeric systems were investigated. A cyano terminated perfluoro alkylene oxide triazine was formulated and partially evaluated. The channel sealant in its present formulation has excellent pressure rupture resistance and surpasses present MIL specifications before and after fuel and heat aging.

  19. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    SciTech Connect

    Pawelec, K. M. E-mail: jw626@cam.ac.uk; Best, S. M.; Cameron, R. E.; Wardale, R. J. E-mail: jw626@cam.ac.uk

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  20. 21 CFR 864.7300 - Fibrin monomer paracoagulation test.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... clotting within a blood vessel) or in the differential diagnosis between disseminated intravascular coagulation and primary fibrinolysis (dissolution of the fibrin in a blood clot). (b) Classification. Class...

  1. 21 CFR 864.7300 - Fibrin monomer paracoagulation test.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... clotting within a blood vessel) or in the differential diagnosis between disseminated intravascular coagulation and primary fibrinolysis (dissolution of the fibrin in a blood clot). (b) Classification. Class...

  2. 21 CFR 864.7300 - Fibrin monomer paracoagulation test.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... clotting within a blood vessel) or in the differential diagnosis between disseminated intravascular coagulation and primary fibrinolysis (dissolution of the fibrin in a blood clot). (b) Classification. Class...

  3. 21 CFR 864.7300 - Fibrin monomer paracoagulation test.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... clotting within a blood vessel) or in the differential diagnosis between disseminated intravascular coagulation and primary fibrinolysis (dissolution of the fibrin in a blood clot). (b) Classification. Class...

  4. Scaffold architecture and fibrin gels promote meniscal cell proliferation

    NASA Astrophysics Data System (ADS)

    Pawelec, K. M.; Best, S. M.; Cameron, R. E.; Wardale, R. J.

    2015-01-01

    Stability of the knee relies on the meniscus, a complex connective tissue with poor healing ability. Current meniscal tissue engineering is inadequate, as the signals for increasing meniscal cell proliferation have not been established. In this study, collagen scaffold structure, isotropic or aligned, and fibrin gel addition were tested. Metabolic activity was promoted by fibrin addition. Cellular proliferation, however, was significantly increased by both aligned architectures and fibrin addition. None of the constructs impaired collagen type I production or triggered adverse inflammatory responses. It was demonstrated that both fibrin gel addition and optimized scaffold architecture effectively promote meniscal cell proliferation.

  5. Cross Linking and Degradation Mechanisms in Model Sealant Candidates

    NASA Technical Reports Server (NTRS)

    Paciorek, K. L.; Kaufman, J.; Ito, T. I.; Nakahara, J. H.; Kratzer, R. H.

    1977-01-01

    Model compounds were investigated as to which type of heterocyclic ring is the most advantageous for curing sealants based on perfluoroalkylether chains. The relative thermal, thermal oxidative, hydrolytic, and fuel stability of potential crosslinks were determined. Specifically substituted materials were synthesized and evaluation of their stabilities in air, inert atmosphere, water, and Jet-A fuel at 235 and 325 C was made. Three heterocyclic ring systems were considered, namely, triazine, 1,2,4- and 1,3,4-oxadiazoles.

  6. Present and future value of dental composite materials and sealants.

    PubMed

    Dogon, I L

    1990-01-01

    This article reviews the development, composition, chemistry, recent technological advances, and extent of use of composite resin restorative materials, adhesives, and pit and fissure sealants. The problems related to the clinical behavior of these materials in the oral environment are dealt with, and methods of minimizing their present deficiencies are suggested. Future directions that might be taken to improve these materials and solve some of the inadequacies that these materials exhibit are also discussed.

  7. In vivo effectiveness of enamel sealants around orthodontic brackets.

    PubMed

    Bechtold, T E; Sobiegalla, A; Markovic, M; Berneburg, M; Göz, G R

    2013-11-01

    In this randomized study, the caries-protective effect on vestibular enamel of two fluoride-containing sealants (Protecto® and Light Bond®) during multibracket treatment was investigated. In all, 40 orthodontic patients about to receive a multibracket appliance with the brackets bonded to the vestibular tooth surfaces were randomly included in this study. Each one was randomly assigned to one of four groups. A crossover design was selected in which a sealed quadrant was contralateral to an unsealed quadrant, then choosing the reverse configuration in the opposite jaw. Two sealants were, thus, tested on vestibular enamel on left and right anterior teeth and premolars in both jaws of each patient over 6 months of multibracket treatment. A DIAGNOdent® pen measuring laser fluorescence was used to analyze the relevant enamel surfaces both at baseline and after 6 months. Neither the incidence nor the characteristics of the demineralization we observed during the study differed between the 4 groups. Single application of smooth-surface sealants did not protect enamel around brackets from incipient carious lesions during the first 6 months of multibracket treatment.

  8. A randomized prospective multicenter trial of a novel vascular sealant.

    PubMed

    Stone, William M; Cull, David L; Money, Samuel R

    2012-11-01

    Increasing use of anticoagulant medications, particularly antiplatelet therapies, can increase the difficulty in obtaining adequate suture line hemostasis. Multiple vascular sealants have been used as adjuncts to surgical procedures, but none of them have been universally successful. The aim of this study was to evaluate the safety and effectiveness of a new prophylactic vascular sealant in arterial surgery. A randomized prospective multi-institutional trial was undertaken comparing ArterX Vascular Sealant (AVS) with Gelfoam Plus during open arterial reconstruction. Three hundred thirty-one anastomotic sites in 217 patients were randomized. One hundred one of 167 (60.5%) anastomotic sites in the AVS group achieved immediate hemostasis compared with 65 of 164 (39.6%) in the control group (P = 0.001). In anastomoses with polytetrafluoroethylene grafts, 105 of 167 (62.5%) in the AVS group achieved immediate hemostasis compared with 56 of 164 (34.0%) in the control group (P < 0.001). No significant differences were noted in morbidity or mortality. Operative time was significantly less in the AVS group compared with the control group (3.2 vs. 3.8 hours, P < 0.01). Use of AVS results in superior hemostatic effectiveness compared with Gelfoam Plus, with no difference in safety. Although no cost analysis was performed, cost savings likely resulted from significantly decreased operative time. Copyright © 2012 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

  9. An accelerated exposure and testing apparatus for building joint sealants

    NASA Astrophysics Data System (ADS)

    White, C. C.; Hunston, D. L.; Tan, K. T.; Hettenhouser, J.; Garver, J. D.

    2013-09-01

    The design, fabrication, and implementation of a computer-controlled exposure and testing apparatus for building joint sealants are described in this paper. This apparatus is unique in its ability to independently control and monitor temperature, relative humidity, ultraviolet (UV) radiation, and mechanical deformation. Each of these environmental factors can be controlled precisely over a wide range of conditions during periods of a month or more. Moreover, as controlled mechanical deformations can be generated, in situ mechanical characterization tests can be performed without removing specimens from the chamber. Temperature and humidity were controlled during our experiments via a precision temperature regulator and proportional mixing of dry and moisture-saturated air; while highly uniform UV radiation was attained by attaching the chamber to an integrating sphere-based radiation source. A computer-controlled stepper motor and a transmission system were used to provide precise movement control. The reliability and effectiveness of the apparatus were demonstrated on a model sealant material. The results clearly show that this apparatus provides an excellent platform to study the long-term durability of building joint sealants.

  10. Compliant sealants for solid oxide fuel cells and other ceramics

    DOEpatents

    Bloom, Ira D.; Ley, Kevin L.

    1995-01-01

    A glass or glass-ceramic sealant for a SOFC having a coefficient of thermal expansion in the range of from about 8 to about 13.times.10.sup.-6 /.degree.C. and a viscosity of at least 10.sup.3 Pa-s at cell operating temperature. The sealant has a composition of SrO present in the range of from about 5 to about 60 mole percent, La.sub.2 O.sub.3 present in the range of from 0 to about 45 mole percent, Al.sub.2 O.sub.3 present in the range from 0 to about 15 mole percent, B.sub.2 O.sub.3 present in the range of from about 15 mole percent to about 80 mole percent, and SiO.sub.2 present in the range of from 0 to about 40 mole percent, wherein the material is a viscous fluid at cell operating temperatures of from about 600.degree. C. to about 1000.degree. C. The sealant may also be compounds of CaO present in the range of from 0 to about 35 mole percent, Al.sub.2 O.sub.3 present in the range from 0 to about 15 mole percent, B.sub.2 O.sub.3 present in the range of from about 35 mole percent to about 85 mole percent, and SiO.sub.2 present in the range of from 0 to about 30 mole percent.

  11. Compliant sealants for solid oxide fuel cells and other ceramics

    DOEpatents

    Bloom, I.D.; Ley, K.L.

    1995-09-26

    A glass or glass-ceramic sealant is described for a SOFC having a coefficient of thermal expansion in the range of from about 8 to about 13{times}10{sup {minus}6}/C and a viscosity of at least 10{sup 3}Pa-s at cell operating temperature. The sealant has a composition of SrO present in the range of from about 5 to about 60 mole percent, La{sub 2}O{sub 3} present in the range of from 0 to about 45 mole percent, Al{sub 2}O{sub 3} present in the range from 0 to about 15 mole percent, B{sub 2}O{sub 3} present in the range of from about 15 mole percent to about 80 mole percent, and SiO{sub 2} present in the range of from 0 to about 40 mole percent, wherein the material is a viscous fluid at cell operating temperatures of from about 600 C to about 1000 C. The sealant may also be compounds of CaO present in the range of from 0 to about 35 mole percent, Al{sub 2}O{sub 3} present in the range from 0 to about 15 mole percent, B{sub 2}O{sub 3} present in the range of from about 35 mole percent to about 85 mole percent, and SiO{sub 2} present in the range of from 0 to about 30 mole percent. 2 figs.

  12. Randomized trial on fluorides and sealants for fissure caries prevention.

    PubMed

    Liu, B Y; Lo, E C M; Chu, C H; Lin, H C

    2012-08-01

    To investigate the effectiveness of topical fluorides in preventing fissure caries, we conducted a randomized controlled trial with parallel groups. In total, 501 children (1,539 molars, 3,078 sites), mean age 9.1 years, who had at least one sound permanent first molar with deep fissures or fissures with signs of early caries were recruited. They were randomly allocated among four groups: (1) resin sealant, single placement; (2) 5% NaF varnish, semi-annual application; (3) 38% silver diamine fluoride (SDF) solution, annual application; and (4) placebo control. Follow-up examinations were conducted every 6 months by a masked examiner. After 24 months, 485 children (97%) were examined. Proportions of pit/fissure sites with dentin caries in the sealant, NaF, SDF, and control groups were 1.6%, 2.4%, 2.2%, and 4.6%, respectively. A multi-level logistic regression analysis accounting for the effects of data clustering and confounding factors showed that fissures in any of the three treatment groups had significantly lower risks of carious cavity development into dentin than did controls (p < 0.05). We concluded that placement of resin sealant, semi-annual application of NaF varnish, and annual application of SDF solution are all effective in preventing pit and fissure caries in permanent molars (ClinicalTrials.gov number CT01446107).

  13. Effect of a surface sealant on the color stability of composite resins after immersion in staining solution.

    PubMed

    Pedroso, Lauana Borges; Barreto, Luma Franciélle Cabreira; Miotti, Leonardo Lamberti; Nicoloso, Gabriel Ferreira; Durand, Leticia Brandão

    2016-01-01

    This study evaluated the influence of surface sealants on the color stability of 2 different composite resins after immersion in coffee. Four groups were created (n = 10): microhybrid composite, microhybrid with surface sealant, nanofilled composite, and nanofilled composite with surface sealant. Half of the specimens of each group were immersed in distilled water and half were immersed in coffee for 48 hours. Color was measured before and after immersion. Groups with surface sealants presented less color variation when compared with the groups without surface sealants. The nanofilled resin specimens presented the greatest color variation within the groups without sealant. The surface sealant positively influenced the color stability of composite resin specimens immersed in coffee. When surface sealant was not applied, the microhybrid specimens had better color stability than the nanofilled.

  14. Image inpainting by patch propagation using patch sparsity.

    PubMed

    Xu, Zongben; Sun, Jian

    2010-05-01

    This paper introduces a novel examplar-based inpainting algorithm through investigating the sparsity of natural image patches. Two novel concepts of sparsity at the patch level are proposed for modeling the patch priority and patch representation, which are two crucial steps for patch propagation in the examplar-based inpainting approach. First, patch structure sparsity is designed to measure the confidence of a patch located at the image structure (e.g., the edge or corner) by the sparseness of its nonzero similarities to the neighboring patches. The patch with larger structure sparsity will be assigned higher priority for further inpainting. Second, it is assumed that the patch to be filled can be represented by the sparse linear combination of candidate patches under the local patch consistency constraint in a framework of sparse representation. Compared with the traditional examplar-based inpainting approach, structure sparsity enables better discrimination of structure and texture, and the patch sparse representation forces the newly inpainted regions to be sharp and consistent with the surrounding textures. Experiments on synthetic and natural images show the advantages of the proposed approach.

  15. Selegiline Transdermal Patch

    MedlinePlus

    ... you can use baby oil or a medical adhesive removal pad to remove residue that will not come off with soap and water. Do not use alcohol, nail polish remover, or other solvents. Apply a new patch to a different area immediately by following steps 1 to 6.

  16. Oxybutynin Transdermal Patch

    MedlinePlus

    ... you can use baby oil or a medical adhesive removal pad to remove residue that will not come off with soap and water. Do not use alcohol, nail polish remover, or other solvents. Apply a new patch to a different area immediately by following steps 1–5.

  17. Nitroglycerin Transdermal Patch

    MedlinePlus

    ... press down on its center to lift the edges away from the skin. Hold the edge gently and slowly peel the patch away from ... your medications or monitor you carefully for side effects.tell your doctor if you think you may ...

  18. Comparison of Microleakage and Penetration Depth between Hydrophilic and Hydrophobic Sealants in Primary Second Molar.

    PubMed

    Gawali, Pritesh N; Chaugule, Vishwas B; Panse, Amey M

    2016-01-01

    Optimal pit and fissure sealing is determined by surface preparation techniques and choice of materials. The performance of pit and fissure sealant materials has been intensively investigated, yet no single product is reported as an ideal sealant. In children, moisture control during cavity preparation is always a big challenge, and hence, hydrophilic sealants have been developed. To compare the microleakage and penetration depth of hydrophilic and hydrophobic sealants using acid-etching on dry and moist surfaces. Recently, extracted 28 2nd primary molars are assigned to two groups (hydrophobic group I; hydrophilic group II) depending on the surface condition (dry group: A1 and B1; moist group: A2 and B2) of 7 teeth in each group. Samples from group A1 and B1 are cleaned and dried with a 3-way syringe and etched with etching gel, and sealant is applied to the fissures and cured with visible light. Sample from A2 and B2 are immersed in 0.1 mL of fresh whole human saliva for 20 seconds and dried using a pellet cotton, and the same procedure is carried out. All samples are subjected to 1000 thermal cycles and sectioned to compare the depth of penetration and microleakage. Sections will be examined under light microscope and analyzed using an image analysis software (SigmaScan). The least microleakage was seen with hydrophilic sealant under moist surface condition, and the depth of penetration of hydrophobic sealant was found to be better than that of hydrophilic sealant in both dry and moist surface conditions. Hydrophilic pit and fissure sealants showed higher tolerance to saliva contamination with less microleakage, but in terms of penetration ability hydrophobic sealants were found to be superior. Gawali PN, Chaugule VB, Panse AM. Comparison of Microleakage and Penetration Depth between Hydrophilic and Hydrophobic Sealants in Primary Second Molar. Int J Clin Pediatr Dent 2016;9(4):291-295.

  19. Monitoring of sound and carious surfaces under sealants over 44 months.

    PubMed

    Fontana, M; Platt, J A; Eckert, G J; González-Cabezas, C; Yoder, K; Zero, D T; Ando, M; Soto-Rojas, A E; Peters, M C

    2014-11-01

    Although there is strong evidence for the effectiveness of sealants, one major barrier in sealant utilization is the concern of sealing over active caries lesions. This study evaluated detection and monitoring of caries lesions through a clear sealant over 44 mo. Sixty-four 7- to 10-year-old children with at least 2 permanent molars with International Caries Detection and Assessment System (ICDAS) scores 0-4 (and caries less than halfway through the dentin, radiographically) were examined with ICDAS, DIAGNOdent, and quantitative light-induced fluorescence (QLF) before sealant placement and 1, 12, 24, and 44 mo (except QLF) after. Bitewing radiographs were taken yearly. DIAGNOdent and QLF were able to distinguish between baseline ICDAS before and after sealant placement. There was no significant evidence of ICDAS progression at 12 mo, but there was small evidence of minor increases at 24 and 44 mo (14% and 14%, respectively) with only 2% ICDAS ≥ 5. Additionally, there was little evidence of radiographic progression (at 12 mo = 1%, 24 mo = 3%, and 44 mo = 9%). Sealant retention rates were excellent at 12 mo = 89%, 24 mo = 78%, and 44 mo = 70%. The small risk of sealant repair increased significantly as baseline ICDAS, DIAGNOdent, and QLF values increased. However, regardless of lesion severity, sealants were 100% effective at 12 mo and 98% effective over 44 mo in managing occlusal surfaces at ICDAS 0-4 (i.e., only 4 of 228 teeth progressed to ICDAS ≥ 5 associated with sealants in need of repair and none to halfway or more through the dentin, radiographically). This study suggests that occlusal surfaces without frank cavitation (ICDAS 0-4) that are sealed with a clear sealant can be monitored with ICDAS, QLF, or DIAGNOdent, which may aid in predicting the need for sealant repair. © International & American Associations for Dental Research.

  20. Monitoring of Sound and Carious Surfaces under Sealants over 44 Months

    PubMed Central

    Fontana, M.; Platt, J.A.; Eckert, G.J.; González-Cabezas, C.; Yoder, K.; Zero, D.T.; Ando, M.; Soto-Rojas, A.E.; Peters, M.C.

    2014-01-01

    Although there is strong evidence for the effectiveness of sealants, one major barrier in sealant utilization is the concern of sealing over active caries lesions. This study evaluated detection and monitoring of caries lesions through a clear sealant over 44 mo. Sixty-four 7- to 10-year-old children with at least 2 permanent molars with International Caries Detection and Assessment System (ICDAS) scores 0-4 (and caries less than halfway through the dentin, radiographically) were examined with ICDAS, DIAGNOdent, and quantitative light-induced fluorescence (QLF) before sealant placement and 1, 12, 24, and 44 mo (except QLF) after. Bitewing radiographs were taken yearly. DIAGNOdent and QLF were able to distinguish between baseline ICDAS before and after sealant placement. There was no significant evidence of ICDAS progression at 12 mo, but there was small evidence of minor increases at 24 and 44 mo (14% and 14%, respectively) with only 2% ICDAS ≥ 5. Additionally, there was little evidence of radiographic progression (at 12 mo = 1%, 24 mo = 3%, and 44 mo = 9%). Sealant retention rates were excellent at 12 mo = 89%, 24 mo = 78%, and 44 mo = 70%. The small risk of sealant repair increased significantly as baseline ICDAS, DIAGNOdent, and QLF values increased. However, regardless of lesion severity, sealants were 100% effective at 12 mo and 98% effective over 44 mo in managing occlusal surfaces at ICDAS 0-4 (i.e., only 4 of 228 teeth progressed to ICDAS ≥ 5 associated with sealants in need of repair and none to halfway or more through the dentin, radiographically). This study suggests that occlusal surfaces without frank cavitation (ICDAS 0-4) that are sealed with a clear sealant can be monitored with ICDAS, QLF, or DIAGNOdent, which may aid in predicting the need for sealant repair. PMID:25248613

  1. A One-Year Evaluation of a Free Fissure Sealant Program.

    PubMed

    M, Bakhtiar; N, Azadi; A, Golkari

    2016-12-01

    Pit and fissure sealant therapy has been approved as an effective measure in the prevention of occlusal dental caries. Resin based materials are the most common materials used worldwide. A variety of resin based fissure sealants are produced and used. Most of them have been presented with ideal results in research environment. However, their effectiveness in the real life, especially in a mass application program such as Iran's oral health reform plan is not clear. To evaluate the longevity of different fissure sealant applied in Iran's oral health reform plan in Fars Province (south of Iran) after one year. Seven counties were selected. One hundred 6- to 8-year-old school children who had undergone fissure sealant therapy in spring 2015 were randomly selected from each county. Their first molars were examined to evaluate the status of the fissure sealants which were applied one year ago. Data on the type/brand of fissure sealant materials, type and experience of clinicians who applied them, existence of a chair-side assistant, and whether the children were caries-free at the time of fissure sealant application were collected from the existing reports. Data of 1974 teeth from 598 children were used for the final analysis. The effects of type/brand of the material was significant on the final results and remained significant (p < 0.001) after adjustments for the level of fluoride, urban/rural area, upper/lower jaw, type of clinician who applied the sealant, existence of a chair-side assistant, and child's gender, age, and being caries-free. Many factors affect the success rate of a fissure sealant therapy program. The type/brand of the material remained significantly related to the success rate of the fissure sealant even after adjustments for other influencing factors. In this study, ClinproTM Sealant (3M/ESPE, USA) showed better longevity after one year of application.

  2. Pit and fissure sealants for preventing dental decay in permanent teeth.

    PubMed

    Ahovuo-Saloranta, Anneli; Forss, Helena; Walsh, Tanya; Nordblad, Anne; Mäkelä, Marjukka; Worthington, Helen V

    2017-07-31

    Dental sealants were introduced in the 1960s to help prevent dental caries, mainly in the pits and fissures of occlusal tooth surfaces. Sealants act to prevent bacteria growth that can lead to dental decay. Evidence suggests that fissure sealants are effective in preventing caries in children and adolescents compared to no sealants. Effectiveness may, however, be related to caries incidence level of the population. This is an update of a review published in 2004, 2008 and 2013. To compare the effects of different types of fissure sealants in preventing caries in occlusal surfaces of permanent teeth in children and adolescents. Cochrane Oral Health's Information Specialist searched: Cochrane Oral Health's Trials Register (to 3 August 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 7), MEDLINE Ovid (1946 to 3 August 2016), and Embase Ovid (1980 to 3 August 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials to 3 August 2016. No restrictions were placed on language or date of publication. Randomised controlled trials (RCTs) comparing sealants with no sealant or a different type of sealant material for preventing caries of occlusal surfaces of premolar or molar teeth in children and adolescents aged up to 20 years. Studies required at least 12 months follow-up. We excluded studies that compared compomers to resins/composites. Two review authors independently screened search results, extracted data and assessed risk of bias of included studies. We presented outcomes for caries or no caries on occlusal surfaces of permanent molar teeth as odds ratio (OR) or risk ratio (RR). We used mean difference (MD) for mean caries increment. All measures were presented with 95% confidence intervals (CI). We conducted meta-analyses using a random-effects model for comparisons where there were more than three trials; otherwise we used the fixed

  3. Patch choice under predation hazard.

    PubMed

    Krivan, V; Vrkoc, I

    2000-12-01

    In this paper we study optimal animal movement in heterogeneous environments consisting of several food patches in which animals trade-off energy gain versus predation risk. We derive a myopic optimization rule describing optimal animal movements by fitness maximization assuming an animal state is described by a single quantity (such as weight, size, or energy reserves). This rule predicts a critical state at which an animal should switch from a more dangerous and more profitable patch to a less dangerous and less profitable patch. Qualitatively, there are two types of behavior: either the animal switches from one patch to another and stays in the new patch for some time before it switches again, or the animal switches between two patches instantaneously. The former case happens if animal state growth is positive in all patches, while the latter case happens if animal state growth is negative in one patch. In particular, this happens if one patch is a refuge. We consider in detail two special cases. The first one assumes a linear animal state growth while the second assumes a saturating animal state growth described by the von Bertalanffy curve. For the first model the proportion of time spent in the more profitable and more risky patch increases with profitability of this patch when state growth is positive in both patches. On contrary, if state growth is negative in the less profitable and safer patch, animals spend proportionally less time in the more profitable and more risky patch as its profitability increases. As a function of the predation risk in the more profitable patch the time spent there proportionally decreases. When animal state growth is described by the saturating curve, time spent in the more risky patch is a hump-shaped curve if state growth is positive in both patches. Our results extend the mu/f rule, which predicts that animals should behave in such a way as to minimize mortality risk to resource intake ratio.

  4. 40 CFR 63.6008 - How do I demonstrate continuous compliance with the emission limitations for puncture sealant...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... compliance with the emission limitations for puncture sealant application affected sources? 63.6008 Section... Puncture Sealant Application Affected Sources § 63.6008 How do I demonstrate continuous compliance with the emission limitations for puncture sealant application affected sources? (a) You must demonstrate...

  5. 40 CFR 63.5988 - What emission limitations must I meet for puncture sealant application affected sources?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... for puncture sealant application affected sources? 63.5988 Section 63.5988 Protection of Environment... Tire Manufacturing Emission Limitations for Puncture Sealant Application Affected Sources § 63.5988 What emission limitations must I meet for puncture sealant application affected sources? (a) You...

  6. 40 CFR 63.6002 - How do I demonstrate initial compliance with the emission limits for puncture sealant application...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... with the emission limits for puncture sealant application affected sources? 63.6002 Section 63.6002... Sealant Application Affected Sources § 63.6002 How do I demonstrate initial compliance with the emission limits for puncture sealant application affected sources? (a) You must demonstrate initial...

  7. 40 CFR 63.5988 - What emission limitations must I meet for puncture sealant application affected sources?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... for puncture sealant application affected sources? 63.5988 Section 63.5988 Protection of Environment... Tire Manufacturing Emission Limitations for Puncture Sealant Application Affected Sources § 63.5988 What emission limitations must I meet for puncture sealant application affected sources? (a) You...

  8. 40 CFR 63.5989 - What are my alternatives for meeting the emission limitations for puncture sealant application...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the emission limitations for puncture sealant application affected sources? 63.5989 Section 63.5989... Hazardous Air Pollutants: Rubber Tire Manufacturing Emission Limitations for Puncture Sealant Application... sealant application affected sources? You must use one of the compliance alternatives in paragraphs...

  9. 40 CFR 63.6002 - How do I demonstrate initial compliance with the emission limits for puncture sealant application...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... with the emission limits for puncture sealant application affected sources? 63.6002 Section 63.6002... Sealant Application Affected Sources § 63.6002 How do I demonstrate initial compliance with the emission limits for puncture sealant application affected sources? (a) You must demonstrate initial...

  10. 40 CFR 63.5989 - What are my alternatives for meeting the emission limitations for puncture sealant application...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the emission limitations for puncture sealant application affected sources? 63.5989 Section 63.5989... Hazardous Air Pollutants: Rubber Tire Manufacturing Emission Limitations for Puncture Sealant Application... sealant application affected sources? You must use one of the compliance alternatives in paragraphs...

  11. Contaminating fibrin in CPD-blood: solubility in plasma and distribution in blood components following separation

    SciTech Connect

    Skjonsberg, O.H.; Kierulf, P.; Gravem, K.; Fagerhol, M.K.; Godal, H.C.

    1986-01-01

    In order to estimate the solubility of contaminating fibrin in CPD-blood, thrombin induced fibrin polymerzation in CPD-plasma was examined by light scattering and fibrinopeptide A (FPA) determinations. In addition, I-125 fibrin monomer enriched CPD-blood was used to investigate fibrin monomer retention in blood bags and transfusion filters (170 microns) and fibrin distribution in blood components derived from CPD-blood. Initial fibrin polymerization in CPD-blood occurred after conversion of 15 per cent of the fibrinogen to fibrin, implying that substantial amounts of fibrin may be kept solubilized in CPD-blood bags. Only minor amounts of I-125 fibrin monomers were retained in blood bags (2.4 per cent) and in transfusion filters (2.9 per cent) after sham transfusions. After separating I-125-fibrin monomer enriched CPD-blood into its constituent components, the major part of fibrin (75.0 per cent) could be traced in the cryoprecipitate.

  12. First Permanent Molar Restoration Differences between Those with or without Dental Sealants.

    ERIC Educational Resources Information Center

    Kuthy, Raymond A.; And Others

    1990-01-01

    The study examined differences in the number of restorations in permanent, posterior teeth for those children receiving dental sealants with cost sharing when compared to children who do not receive sealants. Results indicated a 51 percent reduction in restoration rates for each quadrant sealed. Findings have implications for cost savings and…

  13. Biodegradable-Polymer-Blend-Based Surgical Sealant with Body-Temperature-Mediated Adhesion.

    PubMed

    Behrens, Adam M; Lee, Nora G; Casey, Brendan J; Srinivasan, Priya; Sikorski, Michael J; Daristotle, John L; Sandler, Anthony D; Kofinas, Peter

    2015-12-22

    The development of practical and efficient surgical sealants has the propensity to improve operational outcomes. A biodegradable polymer blend is fabricated as a nonwoven fiber mat in situ. After direct deposition onto the tissue of interest, the material transitions from a fiber mat to a film. This transition promotes polymer-substrate interfacial interactions leading to improved adhesion and surgical sealant performance.

  14. First Permanent Molar Restoration Differences between Those with or without Dental Sealants.

    ERIC Educational Resources Information Center

    Kuthy, Raymond A.; And Others

    1990-01-01

    The study examined differences in the number of restorations in permanent, posterior teeth for those children receiving dental sealants with cost sharing when compared to children who do not receive sealants. Results indicated a 51 percent reduction in restoration rates for each quadrant sealed. Findings have implications for cost savings and…

  15. CAUSES OF POOR SEALANT PERFORMANCE IN SOIL-GAS- RESISTANT FOUNDATIONS

    EPA Science Inventory

    The paper discusses causes of poor sealant performance in soil-gas-resistant foundations. ealants for radon-resistant foundation construction must seal the gap between concrete sections. odern sealants have such low permeability that seal performance depends only on the permeabil...

  16. 40 CFR Table 3 to Subpart Xxxx of... - Emission Limits for Puncture Sealant Application Affected Sources

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... puncture sealant application spray booth Reduce spray booth HAP (measured as VOC) emissions by at least 95... 40 Protection of Environment 13 2012-07-01 2012-07-01 false Emission Limits for Puncture Sealant... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS...

  17. 40 CFR Table 3 to Subpart Xxxx of... - Emission Limits for Puncture Sealant Application Affected Sources

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... puncture sealant application spray booth Reduce spray booth HAP (measured as VOC) emissions by at least 95... 40 Protection of Environment 13 2013-07-01 2012-07-01 true Emission Limits for Puncture Sealant... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS...

  18. 40 CFR Table 3 to Subpart Xxxx of... - Emission Limits for Puncture Sealant Application Affected Sources

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... puncture sealant application spray booth Reduce spray booth HAP (measured as VOC) emissions by at least 95... 40 Protection of Environment 13 2014-07-01 2014-07-01 false Emission Limits for Puncture Sealant... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS...

  19. CAUSES OF POOR SEALANT PERFORMANCE IN SOIL-GAS- RESISTANT FOUNDATIONS

    EPA Science Inventory

    The paper discusses causes of poor sealant performance in soil-gas-resistant foundations. ealants for radon-resistant foundation construction must seal the gap between concrete sections. odern sealants have such low permeability that seal performance depends only on the permeabil...

  20. Current Status of Hemostatic Agents and Sealants in Urologic Surgical Practice

    PubMed Central

    Kommu, Sashi S; McArthur, Robert; Emara, Amr M; Reddy, Utsav D; Anderson, Christopher J; Barber, Neil J; Persad, Raj A; Eden, Christopher G

    2015-01-01

    There has been a recent and near exponential increase in the use of hemostatic agents and sealants to supplement the rapidly evolving methods in the surgical management of urologic patients. This article reviews the use of hemostatic agents and sealants in current urologic practice. PMID:26543429

  1. Qualification, Demonstration & Validation of Compliant Removers for Aircraft Sealants and Specialty Coatings ESTCP WP-0621

    DTIC Science & Technology

    2010-06-01

    materials/ methods to approach sealant removal tasks consistently and effectively, depending upon situation. BUSINESS SENSITIVE 6 TECHNICAL APROACH ...Dem/Val 3 at New River MCAS - V-22 Osprey TECHNICAL APROACH BUSINESS SENSITIVE 5 TECHNICAL APROACH “Toolbox” Approach: Provide end users with...Demonstration Tests (UDRI) - Testing Protocols Parameter Test Test Method Sealant Removal Force Measuring Unit UDRI Proprietary Substrate Damage Potential

  2. [The observation of the contained fluoride sealant on caries prevention for 3 years

    PubMed

    Feng, X P; Li, G L; Dogon, L

    1997-06-01

    Pit and fissure sealant is an effective method for preventing pit and fissure caries,though it has less effect in smooth surface teeth.But the contained sealant is effective on caries prevention both in pit and fissure area and in smooth surface.The aim of the present search was observing the clinic results of the contained fluoride sealant on caries prevention.786 children aged 6-8 years old were divided into four groups.The first permanent molars in group 1 were sealed by the contained fluoride sealant and those in group 2 were used the conventional sealant.The same molars in group 3 were used the conventional sealant plus the APFI gel and those in group 4 were only used the APFI gel.APFI gel was used one time per half year.The results showed the caries preventive effect of the contained fluoride sealant was significant higher than the conventional sealant or the APFI gel in first molars which had been sealed for three years.The caries incidence of the unsealed teeth in group 1 was lower than that in the other groups.The results also indicated the caries preventive effect of all above methods was less in female than in male.

  3. Design, development, and testing of a hybrid in situ testing device for building joint sealant

    Treesearch

    C. White; N. Embree; C. Buch; R.S. Williams

    2005-01-01

    The testing of sealant samples has been restricted to devices that either focus on fatiguing multiple samples or quantifying the mechanical properties of a single sample. This manuscript describes a device that combines these two instrumental designs: the ability to both fatigue and characterize multiple sealant samples at the same time. This device employs precise...

  4. Circulating Microparticles Alter Formation, Structure, and Properties of Fibrin Clots

    PubMed Central

    Zubairova, Laily D.; Nabiullina, Roza M.; Nagaswami, Chandrasekaran; Zuev, Yuriy F.; Mustafin, Ilshat G.; Litvinov, Rustem I.; Weisel, John W.

    2015-01-01

    Despite the importance of circulating microparticles in haemostasis and thrombosis, there is limited evidence for potential causative effects of naturally produced cell-derived microparticles on fibrin clot formation and its properties. We studied the significance of blood microparticles for fibrin formation, structure, and susceptibility to fibrinolysis by removing them from platelet-free plasma using filtration. Clots made in platelet-free and microparticle-depleted plasma samples from the same healthy donors were analyzed in parallel. Microparticles accelerate fibrin polymerisation and support formation of more compact clots that resist internal and external fibrinolysis. These variations correlate with faster thrombin generation, suggesting thrombin-mediated kinetic effects of microparticles on fibrin formation, structure, and properties. In addition, clots formed in the presence of microparticles, unlike clots from the microparticle-depleted plasma, contain 0.1–0.5-μm size granular and CD61-positive material on fibres, suggesting that platelet-derived microparticles attach to fibrin. Therefore, the blood of healthy individuals contains functional microparticles at the levels that have a procoagulant potential. They affect the structure and stability of fibrin clots indirectly through acceleration of thrombin generation and through direct physical incorporation into the fibrin network. Both mechanisms underlie a potential role of microparticles in haemostasis and thrombosis as modulators of fibrin formation, structure, and resistance to fibrinolysis. PMID:26635081

  5. Pit and fissure sealants in dental public health – application criteria and general policy in Finland

    PubMed Central

    Kervanto-Seppälä, Sari; Pietilä, Ilpo; Meurman, Jukka H; Kerosuo, Eero

    2009-01-01

    Background Pit and fissure sealants (sealants) are widely used as a non-operative preventive method in public dental health in Finland. Most children under 19 years of age attend the community-organized dental health services free of charge. The aims of this study were to find out to what extent sealants were applied, what the attitudes of dental professionals towards sealant application were, and whether any existing sealant policies could be detected among the health centres or among the respondents in general. The study evaluated changes that had taken place in the policies used during a ten year period (1991–2001). Methods A questionnaire was mailed to each chief dental officer (CDO) of the 265 public dental health centres in Finland, and to a group of general dentists (GDP) applying sealants in these health centres, giving a total of 434 questionnaires with 22 questions. The response rate was 80% (N = 342). Results A majority of the respondents reported to application of sealants on a systematic basis for children with increased caries risk. The criteria for applying sealants and the actual strategies seemed to vary locally between the dentists within the health centres and between the health centres nationwide. The majority of respondents believed sealants had short- and long-term effects. The overall use of sealants decreased towards the end of the ten year period. The health centres (N = 28) choosing criteria to seal over detected or suspected enamel caries lesion had a DMFT value of 1.0 (SD ± 0.49) at age 12 (year 2000) compared to a value of 1.2 (SD ± 0.47) for those health centres (N = 177) applying sealants by alternative criteria (t-test, p < 0.05). Conclusion There seems to be a need for defined guidelines for sealant application criteria and policy both locally and nationwide. Occlusal caries management may be improved by shifting the sealant policy from the traditional approach of prevention to interception, i.e. applying the sealants over

  6. Rheological characterization of human fibrin and fibrin-agarose oral mucosa substitutes generated by tissue engineering.

    PubMed

    Rodríguez, I A; López-López, M T; Oliveira, A C X; Sánchez-Quevedo, M C; Campos, A; Alaminos, M; Durán, J D G

    2012-08-01

    In regenerative medicine, the generation of biocompatible substitutes of tissues by in vitro tissue engineering must fulfil certain requirements. In the case of human oral mucosa, the rheological properties of tissues deserve special attention because of their influence in the acoustics and biomechanics of voice production. This work is devoted to the rheological characterization of substitutes of the connective tissue of the human oral mucosa. Two substitutes, composed of fibrin and fibrin-agarose, were prepared in cell culture for periods in the range 1-21 days. The time evolution of the rheological properties of both substitutes was studied by two different experimental procedures: steady-state and oscillatory measurements. The former allows the plastic behaviour of the substitutes to be characterized by estimating their yield stress; the latter is employed to quantify their viscoelastic responses by obtaining the elastic (G') and viscous (G'') moduli. The results demonstrate that both substitutes are characterized by a predominant elastic response, in which G' (order 100 Pa) is roughly one order of magnitude larger than G'' (order 10 Pa). But the most relevant insight is the stability, throughout the 21 days of culture time, of the rheological quantities in the case of fibrin-agarose, whereas the fibrin substitute shows a significant hardening. This result provides evidence that the addition to fibrin of a small amount of agarose allows the rheological stability of the oral mucosa substitute to be maintained. This feature, together with its viscoelastic similitude with native tissues, makes this biomaterial appropriate for potential use as a scaffold in regenerative therapies of human oral mucosa. Copyright © 2011 John Wiley & Sons, Ltd.

  7. Clinical Evaluation of the Retention of Different Pit and Fissure Sealants: A 1-Year Study

    PubMed Central

    Kumaran, Parvathy

    2013-01-01

    ABSTRACT Objective: The aim of this study was to evaluate the retention of different pit and fissure sealants on the first permanent molars over a period of one year. Materials and methods: In this study, a total of 40 children with all first permanent molars erupted received four different pit and fissure sealants. The children were evaluated at 6 and 12 months. Results: The data was subjected to Chi-square test and Kaplan Meier survival analysis. The p-value was calculated using Wilcoxon matched-pairs signed-rank test. Conclusion: The retention rates of resin-based sealants were superior to that of glass ionomer sealant. How to cite this article: Kumaran P. Clinical Evaluation of the Retention of Different Pit and Fissure Sealants: A 1-Year Study. Int J Clin Pediatr Dent 2013;6(3):183-187. PMID:25206219

  8. Fibrin gels and their clinical and bioengineering applications

    PubMed Central

    Janmey, Paul A; Winer, Jessamine P; Weisel, John W

    2008-01-01

    Fibrin gels, prepared from fibrinogen and thrombin, the key proteins involved in blood clotting, were among the first biomaterials used to prevent bleeding and promote wound healing. The unique polymerization mechanism of fibrin, which allows control of gelation times and network architecture by variation in reaction conditions, allows formation of a wide array of soft substrates under physiological conditions. Fibrin gels have been extensively studied rheologically in part because their nonlinear elasticity, characterized by soft compliance at small strains and impressive stiffening to resist larger deformations, appears essential for their function as haemostatic plugs and as matrices for cell migration and wound healing. The filaments forming a fibrin network are among the softest in nature, allowing them to deform to large extents and stiffen but not break. The biochemical and mechanical properties of fibrin have recently been exploited in numerous studies that suggest its potential for applications in medicine and bioengineering. PMID:18801715

  9. Autologous fibrin adhesive in experimental tubal anastomosis.

    PubMed

    Rajaram, S; Rusia, U; Agarwal, S; Agarwal, N

    1996-01-01

    To evaluate autologous fibrin in rabbit oviduct anastomosis versus 7-0 vikryl, a conventional suture material used in tubal anastomosis. Thrombin was added to the autologous fibrinogen at the site of anastomosis to obtain a tissue adhesive. The anastomotic time, pregnancy rate, and litter size were evaluated. Three months later, a relaparotomy was done to evaluate patency and degree of adhesions, and a tubal biopsy was taken from the site of anastomosis. Analysis of results showed a statistically significant (P < .001) shortened anastomotic time and superior histopathological union in the tissue adhesive group. Patency rate, pregnancy rate, and degree of adhesions were comparable in both groups.

  10. Spin Glass Patch Planting

    NASA Technical Reports Server (NTRS)

    Wang, Wenlong; Mandra, Salvatore; Katzgraber, Helmut G.

    2016-01-01

    In this paper, we propose a patch planting method for creating arbitrarily large spin glass instances with known ground states. The scaling of the computational complexity of these instances with various block numbers and sizes is investigated and compared with random instances using population annealing Monte Carlo and the quantum annealing DW2X machine. The method can be useful for benchmarking tests for future generation quantum annealing machines, classical and quantum mechanical optimization algorithms.

  11. Polymer concrete patching manual

    NASA Astrophysics Data System (ADS)

    Fontana, J. J.; Bartholomew, J.

    1982-06-01

    The practicality of using polymer concrete to repair deteriorated portland cement concrete bridge decks and pavements was demonstrated. This manual outlines the procedures for using polymer concrete as a rapid patching material to repair deteriorated concrete. The process technology, materials, equipment, and safety provisions used in manufacturing and placing polymer concrete are discussed. Potential users are informed of the various steps necessary to insure successful field applications of the material.

  12. exp 19 patch-1

    NASA Image and Video Library

    2008-12-03

    ISS019-S-001 (December 2008) --- Expedition 19 marks the final planned period of three person occupancy, prior to increasing the crew size to 6, and occurs in the final stages of International Space Station assembly. The patch emphasizes the earth, one of the major focuses of attention and study from the orbital research outpost. The design is stylized to highlight the beauty of the home planet and the station orbiting it, next to the sun now the unquestioned

  13. exp 19 patch-1

    NASA Image and Video Library

    2009-12-29

    ISS019-S-001A (December 2008) --- Expedition 19 marks the final planned period of three person occupancy, prior to increasing the crew size to 6, and occurs in the final stages of International Space Station assembly. The patch emphasizes the earth, one of the major focuses of attention and study from the orbital research outpost. The design is stylized to highlight the beauty of the home planet and the station orbiting it, next to the sun now the unquestioned

  14. Research and analysis of patch shape on microstrip patch antenna

    NASA Astrophysics Data System (ADS)

    Ji, Ai-guo; Wang, Peng

    2017-01-01

    The shape of the radiating patch in the microstrip patch antenna is one of the many factors that affect the performance of the microstrip antenna.In this paper, on the premise of center frequency of 2.45 GHz, rectangular, circular and triangular microstrip patch antennas are designed and simulated respectively.The simulation results of the three microstrip patch antenna are analyzed, such as feed point position, return loss and radiation patterns.The influence of the shape of the radiation patch on the impedance bandwidth, gain and directivity of microstrip antennas is discussed.The simulation results show that the comprehensive performance of rectangular microstrip patch antenna is better than the other two, the comprehensive performance of triangular microstrip patch antenna is poor.

  15. Global Patch Matching

    NASA Astrophysics Data System (ADS)

    Huang, X.; Hu, K.; Ling, X.; Zhang, Y.; Lu, Z.; Zhou, G.

    2017-09-01

    This paper introduces a novel global patch matching method that focuses on how to remove fronto-parallel bias and obtain continuous smooth surfaces with assuming that the scenes covered by stereos are piecewise continuous. Firstly, simple linear iterative cluster method (SLIC) is used to segment the base image into a series of patches. Then, a global energy function, which consists of a data term and a smoothness term, is built on the patches. The data term is the second-order Taylor expansion of correlation coefficients, and the smoothness term is built by combing connectivity constraints and the coplanarity constraints are combined to construct the smoothness term. Finally, the global energy function can be built by combining the data term and the smoothness term. We rewrite the global energy function in a quadratic matrix function, and use least square methods to obtain the optimal solution. Experiments on Adirondack stereo and Motorcycle stereo of Middlebury benchmark show that the proposed method can remove fronto-parallel bias effectively, and produce continuous smooth surfaces.

  16. Biocide patch tests.

    PubMed

    Andersen, K E; Veien, N K

    1985-02-01

    Routine patch testing with a series of 6 industrial biocides containing methylene-bis-thiocyanate (Cytox 3522), benzisothiazolin-3-one (BIT), chlorocresol (Preventol CMK), 2-n-octyl-4-isothiazolin-3-one (Kathon 893), polyhydroxymethylene monobenzylether (Preventol D2) or 1,3,5-tris (hydroxy-ethyl) hexahydrotriazine (Grotan BK) was carried out in 6 Danish out-patient clinics to evaluate guinea pig allergy test results with the same compounds. A total of 1652 consecutive patients with dermatitis were tested. The usefulness of this patch test battery was limited. There were a few positive reactions to Cytox 3522, BIT and the 2 formaldehyde releasers, Preventol D2 and Grotan BK. These reactions could not, however, be explained. The MOAHL-index (% of Male patients, Occupational cases, Atopic patients, Hand eczemas, and Leg ulcers/stasis dermatitis) for patients from the 6 clinics showed equal frequencies of male patients and atopics, but significant differences in the frequencies of occupational cases, hand eczemas, and leg ulcers/stasis dermatitis, indicating possible variations in referral patterns, use of patch tests, and/or environmental factors.

  17. Exp 36 Patch Final

    NASA Image and Video Library

    2012-08-10

    ISS036-S-001 (January 2012) --- The dynamic design of the Expedition 36 patch portrays the International Space Station?s (ISS) iconic solar arrays. The slanted angles denote a kinetic energy leading from the Earth in the lower right to the upper left tip of the triangular shape of the patch, representing the infinite scientific research, education, and long-duration spaceflight capabilities the ISS provides with each mission, as well as our goal for future exploration beyond the Space Station. The numbers 3 and 6 harmoniously intertwine to form expedition number 36 and its gray coloration signifies the unity and neutrality among all of the international partners of the ISS. The blue and gold color scheme of the patch represents the subtle way the central gold orbit wraps around the number 36 to form a trident at its lower right tip. The trident also symbolizes the sea, air, and land, all of which make up the Earth from where the trident originates in the design. The NASA insignia design for shuttle and space station flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, it will be publicly announced. Photo credit: NASA

  18. Effect of pit and fissure sealants on caries detection by a fluorescent camera system.

    PubMed

    Markowitz, Kenneth; Rosenfeld, Dalia; Peikes, Daniel; Guzy, Gerald; Rosivack, Glenn

    2013-07-01

    The aim of this study was to evaluate the effect of sealant placement on the detection of caries by a fluorescent camera (FC), the Spectra caries detector. In a laboratory study, FC images and readings were obtained from 31 extracted teeth, before and following application of clear sealants (Shofu Clear or Delton unfilled), or opaque sealants (3M Clinpro or Delton FS). Teeth were then sectioned and examined for enamel or dentine caries. Using each tooth's true caries diagnosis, the sensitivity and specificity of the FC measurements in detecting dentine caries was calculated. In the clinical study, FC readings were obtained from 41 molars in children prior to and following application of clear sealants. Following application of Shofu or Delton unfilled there were reductions in the mean FC readings of 10% (p=0.5) and 8.2% (p=0.009), respectively. Application of two opaque sealants, 3M or Delton FS significantly reduced mean FC readings 16.2% and 20.8% (p<0.5), respectively. Although the carious lesions could still be observed in FC images from teeth with opaque sealants there was a significant loss of sensitivity in detecting dentinal caries. Clear sealant application caused an insignificant loss of detection sensitivity. Following application of clear sealants to children's molars there was a small (4.01%) but significant (p<0.01) reduction in FC readings recorded from these teeth. The FC can detect caries under clear sealants with little loss of sensitivity. Although lesions can be seen through opaque sealants, loss of sensitivity precludes accurate lesion assessment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Do light cured ART conventional high-viscosity glass-ionomer sealants perform better than resin-composite sealants: a 4-year randomized clinical trial.

    PubMed

    Zhang, WeiWei; Chen, Xi; Fan, Ming-Wen; Mulder, Jan; Huysmans, Marie-Charlotte C D N J M; Frencken, Jo E

    2014-05-01

    The hypotheses tested were: the cumulative survival rates of dentin caries lesion-free pits and fissures of ART conventional high-viscosity glass-ionomer sealants with light-curing (high-intensity LED) and glass-carbomer sealants are higher than those of conventional ART sealants and resin-composite sealants after 4 years. The randomized controlled clinical trial covered 405 children (mean age 8-years). Three dentists placed sealants in pits and fissures of high caries-risk children. Evaluation by two independent evaluators was conducted after 0.5, 1, 2, 3 and 4 years. The Kaplan-Meier survival method, ANOVA and t-test were used in data analyses. 1304 first permanent molars were sealed. 12.3% of children and 15.4% of sealants dropped out. 46 re-exposed pits and fissures, 39 (occlusal) 7 (free smooth surfaces), in 42 children developed a dentin carious lesion. The cumulative survival of dentin caries lesion-free occlusal pits and fissures in ART plus LED group (98%) was statistically significantly higher than in the resin-composite group (96.4%) and in the glass-carbomer group (94.5%). The cumulative survival of dentin caries lesion-free occlusal pits and fissures in the glass-carbomer group was statistically significantly lower than that in the conventional ART group (97.3%). For the free smooth surfaces, there was no statistically significantly difference among the four sealant groups. Light-cured ART conventional high-viscosity glass-ionomer sealants prevented the occurrence of dentin cavities best. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  20. Con-Patch: When a Patch Meets Its Context.

    PubMed

    Romano, Yaniv; Elad, Michael

    2016-09-01

    Measuring the similarity between the patches in images is a fundamental building block in various tasks. Naturally, the patch size has a major impact on the matching quality and on the consequent application performance. Under the assumption that our patch database is sufficiently sampled, using large patches (e.g., 21 × 21 ) should be preferred over small ones (e.g., 7 × 7 ). However, this dense-sampling assumption is rarely true; in most cases, large patches cannot find relevant nearby examples. This phenomenon is a consequence of the curse of dimensionality, stating that the database size should grow exponentially with the patch size to ensure proper matches. This explains the favored choice of small patch size in most applications. Is there a way to keep the simplicity and work with small patches while getting some of the benefits that large patches provide? In this paper, we offer such an approach. We propose to concatenate the regular content of a conventional (small) patch with a compact representation of its (large) surroundings-its context. Therefore, with a minor increase of the dimensions (e.g., with additional ten values to the patch representation), we implicitly/softly describe the information of a large patch. The additional descriptors are computed based on a self-similarity behavior of the patch surrounding. We show that this approach achieves better matches, compared with the use of conventional-size patches, without the need to increase the database-size. Also, the effectiveness of the proposed method is tested on three distinct problems: 1) external natural image denoising; 2) depth image super-resolution; and 3) motion-compensated frame-rate up conversion.

  1. Tracheal reconstruction using chondrocytes seeded on a poly(L-lactic-co-glycolic acid)-fibrin/hyaluronan.

    PubMed

    Hong, Hyun Jun; Chang, Jae Won; Park, Ju-Kyeong; Choi, Jae Won; Kim, Yoo Suk; Shin, Yoo Seob; Kim, Chul-Ho; Choi, Eun Chang

    2014-11-01

    Reconstruction of trachea is still a clinical dilemma. Tissue engineering is a recent and promising concept to resolve this problem. This study evaluated the feasibility of allogeneic chondrocytes cultured with fibrin/hyaluronic acid (HA) hydrogel and degradable porous poly(L-lactic-co-glycolic acid) (PLGA) scaffold for partial tracheal reconstruction. Chondrocytes from rabbit articular cartilage were expanded and cultured with fibrin/HA hydrogel and injected into a 5 × 10 mm-sized, curved patch-shape PLGA scaffold. After 4 weeks in vitro culture, the scaffold was implanted on a tracheal defect in eight rabbits. Six and 10 weeks postoperatively, the implanted sites were evaluated by bronchoscope and radiologic and histologic analyses. Ciliary beat frequency (CBF) of regenerated epithelium was also evaluated. None of the eight rabbits showed any sign of respiratory distress. Bronchoscopic examination did not reveal stenosis of the reconstructed trachea and the defects were completely recovered with respiratory epithelium. Computed tomography scan showed good luminal contour of trachea. Histologic data showed that the implanted chondrocytes successfully formed neocartilage with minimal granulation tissue. CBF of regenerated epithelium was similar to that of normal epithelium. Partial tracheal defect was successfully reconstructed anatomically and functionally using allogeneic chondrocytes cultured with PLGA-fibrin/HA composite scaffold.

  2. Concentration of fibrin and presence of plasminogen affect proliferation, fibrinolytic activity, and morphology of human fibroblasts and keratinocytes in 3D fibrin constructs.

    PubMed

    Reinertsen, Erik; Skinner, Michael; Wu, Benjamin; Tawil, Bill

    2014-11-01

    Fibrin is a hemostatic protein found in the clotting cascade. It is used in the operating room to stop bleeding and deliver cells and growth factors to heal wounds. However, formulations of clinically approved fibrin are optimized for hemostasis, and the extent to which biochemical and physical cues in fibrin mediate skin cell behavior is not fully understood nor utilized in the design of biomaterials. To determine if the concentration of fibrinogen and the presence of plasminogen affect cell behavior relevant to wound healing, we fabricated three-dimensional fibrin constructs made from 5, 10, or 20 mg/mL of clinical fibrin or plasminogen-depleted (PD) fibrin. We cultured dermal fibroblasts or epidermal keratinocytes in these constructs. Fibroblasts proliferated similarly in both types of fibrin, but keratinocytes proliferated more in low concentrations of clinical fibrin and less in PD fibrin. Clinical fibrin constructs with fibroblasts were less stiff and degraded faster than PD fibrin constructs with fibroblasts. Similarly, keratinocytes degraded clinical fibrin, but not PD fibrin. Fibroblast spreading varied with fibrin concentration in both types of fibrin. In conclusion, the concentration of fibrinogen and the presence of plasminogen affect fibroblast and keratinocyte proliferation, morphology, and fibrin degradation. Creating materials with heterogeneous regions of fibrin formulations and concentrations could be a novel strategy for controlling the phenotype of encapsulated fibroblasts and keratinocytes, and the subsequent biomechanical properties of the construct. However, other well-investigated aspects of wound healing remain to be utilized in the design of fibrin biomaterials, such as autocrine and paracrine signaling between fibroblasts, keratinocytes, and immune cells.

  3. Patch Test Negative Generalized Dermatitis.

    PubMed

    Spiker, Alison; Mowad, Christen

    2016-01-01

    Allergic contact dermatitis is a common condition in dermatology. Patch testing is the criterion standard for diagnosis. However, dermatitis is not always caused by an allergen, and patch testing does not identify a culprit in every patient. Generalized dermatitis, defined as eczematous dermatitis affecting greater than 3 body sites, is often encountered in dermatology practice, especially patch test referral centers. Management for patients with generalized dermatitis who are patch test negative is challenging. The purpose of this article is to outline an approach to this challenging scenario and summarize the paucity of existing literature on patch test negative generalized dermatitis.

  4. Fissure sealant materials: Wear resistance of flowable composite resins

    PubMed Central

    Asefi, Sohrab; Eskandarion, Solmaz; Hamidiaval, Shadi

    2016-01-01

    Background. Wear resistance of pit and fissure sealant materials can influence their retention. Wear characteristics of sealant materials may determine scheduling of check-up visits. The aim of this study was to compare wear resistance of two flowable composite resins with that of posterior composite resin materials. Methods. Thirty-five disk-shaped specimens were prepared in 5 groups, including two flowable composite resins (Estelite Flow Quick and Estelite Flow Quick High Flow), Filtek P90 and Filtek P60 and Tetric N-Ceram. The disk-shaped samples were prepared in 25-mm diameter by packing them into a two-piece aluminum mold and then light-cured. All the specimens were polished for 1minute using 600-grit sand paper. The samples were stored in distilled water at room temperature for 1 week and then worn by two-body abrasion test using "pin-on-disk" method (with distilled water under a 15-Nload at 0.05 m/s, for a distance of 100 meter with Steatite ceramic balls antagonists). A Profilometer was used for evaluating the surface wear. Data were analyzed with the one-way ANOVA. Results. Estelite Flow Quick exhibited 2708.9 ± 578.1 μm2 and Estelite Flow Quick High Flow exhibited 3206 ± 2445.1 μm2of wear but there were no significant differences between the groups. They demonstrated similar wear properties. Conclusion. Estelite flowable composite resins have wear resistance similar to nano- and micro-filled and micro-hybrid composite resins. Therefore, they can be recommended as pit and fissure sealant materials in the posterior region with appropriate mechanical characteristics. PMID:27651887

  5. Prospective evaluation of biodegradable polymeric sealant for intraoperative air leaks.

    PubMed

    Park, Bernard J; Snider, John M; Bates, Nathan R; Cassivi, Stephen D; Jett, G Kimble; Sonett, Joshua R; Toloza, Eric M

    2016-12-12

    A biodegradable polymeric sealant has been previously shown to reduce postoperative air leaks after open pulmonary resection. The aim of this study was to evaluate safety and efficacy during minimally invasive pulmonary resection. In a multicenter prospective single-arm trial, 112 patients with a median age of 69 years (range 34-87 years) were treated with sealant for at least one intraoperative air leak after standard methods of repair (sutures, staples or cautery) following minimally invasive pulmonary resection (Video-Assisted Thoracic Surgery (VATS) or Robotic-Assisted). Patients were followed in hospital and 1 month after surgery for procedure-related and device-related complications and presence of air leak. Forty patients had VATS and 72 patients had Robotic-Assisted procedures with the majority (80/112, 71%) undergoing anatomic resection (61 lobectomy, 13 segmentectomy, 6 bilobectomy). There were no device-related adverse events. The overall morbidity rate was 41% (46/112), with major complications occurring in 16.1% (18/112). In-hospital mortality and 30-day mortality were 1.9% (2/103). The majority of intraoperative air leaks (107/133, 81%) were sealed after sealant application, and an additional 16% (21/133) were considered reduced. Forty-nine percent of patients (55/112) were free of air leak throughout the entire postoperative study period. Median chest tube duration was 2 days (range 1 - 46 days), and median length of hospitalization was 3 days (range 1 - 20 days). This study demonstrated that use of a biodegradable polymer for closure of intraoperative air leaks as an adjunct to standard methods is safe and effective following minimally invasive pulmonary resection. ClinicalTrials.gov: NCT01867658 . Registered 3 May 2013.

  6. Fissure sealant materials: Wear resistance of flowable composite resins.

    PubMed

    Asefi, Sohrab; Eskandarion, Solmaz; Hamidiaval, Shadi

    2016-01-01

    Background. Wear resistance of pit and fissure sealant materials can influence their retention. Wear characteristics of sealant materials may determine scheduling of check-up visits. The aim of this study was to compare wear resistance of two flowable composite resins with that of posterior composite resin materials. Methods. Thirty-five disk-shaped specimens were prepared in 5 groups, including two flowable composite resins (Estelite Flow Quick and Estelite Flow Quick High Flow), Filtek P90 and Filtek P60 and Tetric N-Ceram. The disk-shaped samples were prepared in 25-mm diameter by packing them into a two-piece aluminum mold and then light-cured. All the specimens were polished for 1minute using 600-grit sand paper. The samples were stored in distilled water at room temperature for 1 week and then worn by two-body abrasion test using "pin-on-disk" method (with distilled water under a 15-Nload at 0.05 m/s, for a distance of 100 meter with Steatite ceramic balls antagonists). A Profilometer was used for evaluating the surface wear. Data were analyzed with the one-way ANOVA. Results. Estelite Flow Quick exhibited 2708.9 ± 578.1 μm(2) and Estelite Flow Quick High Flow exhibited 3206 ± 2445.1 μm(2)of wear but there were no significant differences between the groups. They demonstrated similar wear properties. Conclusion. Estelite flowable composite resins have wear resistance similar to nano- and micro-filled and micro-hybrid composite resins. Therefore, they can be recommended as pit and fissure sealant materials in the posterior region with appropriate mechanical characteristics.

  7. Measurement of Fibrin Fiber Strength using AFM

    NASA Astrophysics Data System (ADS)

    Jawerth, Louise; Falvo, Mchael; Canning, Anthony; Matthews, Garrett; Superfine, Richard; Guthold, Martin

    2003-11-01

    Blood clots usually form in the event of injury or damage to blood vessels to prevent the loss of blood. Moreover, as we age, blood clots often form in undesired locations, i.e. in blood vessels around the heart or brain, or in uninjured vessels resulting in heart attacks or strokes. Fibrin fibers, the skeleton of a blood clot, essentially perform the mechanical task of creating a blockage that stems blood flow. Thus, a better understanding of the mechanical properties of these fibers, such as the tensile strength and Young's modulus, will enhance our understanding of blood clots. For quantitative stress and strain measurements, we need to image the deformation of the fiber and measure the applied force simultaneously. For this reason, we are combining fluorescent microscopy with atomic force microscopy. Fibrin fibers were fluorescently labeled with streptavidin-coated quantum dots and deposited on a functionalized glass substrate, imaged and manipulated under buffer. We will describe our progress in obtaining quantitative lateral force measurements under buffer simultaneous with strain measurements from optical microscope images.

  8. Adhesive strength of autologous fibrin glue.

    PubMed

    Yoshida, H; Hirozane, K; Kamiya, A

    2000-03-01

    To establish an easy and rapid method for measuring the adhesive strength of fibrin glue and to clarify the factor(s) most affecting the strength, a study was made on the effect of the concentration of plasma components on the strength of cryoprecipitate (Cryo) prepared from a subject's own autologous plasma to be used as fibrin glue. The adhesive strength of the Cryo was measured with various supporting materials instead of animal skin using a tester of tension and compression. The results were as follows: (1) the strength of Cryo applied to ground flat glass (4 cm2) was significantly greater than that applied to clear glass, clear plastic, or smooth and flat wood chips; (2) the adhesive strength of Cryo depended on the concentration of thrombin with the optimal concentration being 50 units/ml; (3) the concentration of CaCl2 did not affect the adhesive strength of Cryo; (4) the adhesive reaction was dependent on the temperature and the adhesive strength more quickly reached a steady state at 37 degrees C than at lower temperature; (5) the adhesive strength was correlated well with the total concentration of fibrinogen and fibronectin. These results indicate that the adhesive strength of Cryo can be easily and quickly evaluated using a tester and ground glass with thrombin at 50 units/ml, and that the adhesive strength of Cryo can be predicted from the total concentration of fibrinogen and fibronectin.

  9. Effect of Adhesive Application on Sealant Success: A Clinical Study of Fifth and Seventh Generation Adhesive Systems.

    PubMed

    Tandon, Vaibhav; Lingesha, Ravishanakar Telgi; Tangade, Pradeep Shankar; Tirth, Amit; Pal, Sumit Kumar; Lingesha, Chaitra Telgi; Arora, Vikram; Yadav, Vipul

    2015-10-01

    The aim of the study was to compare the effect of fifth and seventh generation bonding agent on sealant success. Sixty-four school children aged six to nine years received sealants in four permanent molars in a split mouth design, such that each patient received sealant in the first permanent molar with fifth generation bonding agent in one arch and seventh generation bonding agent in the other arch; contra-lateral molars were sealed with sealant alone. The evaluation was carried out at baseline, three months, six months and 12 months, according to the criteria by Feigal et al, in 2000. Chi- square test was used to analyze data at P<0.05 level of significance. Statistically significant differences were found for sealant retention between fifth generation and sealant group, and fifth generation and seventh generation groups; whereas, no significant difference was found for sealant retention between seventh generation and sealant group at three, six and 12 months. As separate etch and rinse steps are not required for seventh generation bonding agents, and almost similar results were obtained for both sealant and seventh generation groups, it can be concluded that application of sealant along with a seventh generation bonding agent may enhance sealant success and can be used for caries prevention in preventive programs.

  10. Effect of Adhesive Application on Sealant Success: A Clinical Study of Fifth and Seventh Generation Adhesive Systems

    PubMed Central

    Tandon, Vaibhav; Tangade, Pradeep Shankar; Tirth, Amit; Pal, Sumit Kumar; Lingesha, Chaitra Telgi; Arora, Vikram; Yadav, Vipul

    2015-01-01

    Objectives: The aim of the study was to compare the effect of fifth and seventh generation bonding agent on sealant success. Materials and Methods: Sixty-four school children aged six to nine years received sealants in four permanent molars in a split mouth design, such that each patient received sealant in the first permanent molar with fifth generation bonding agent in one arch and seventh generation bonding agent in the other arch; contra-lateral molars were sealed with sealant alone. The evaluation was carried out at baseline, three months, six months and 12 months, according to the criteria by Feigal et al, in 2000. Chi- square test was used to analyze data at P<0.05 level of significance. Results: Statistically significant differences were found for sealant retention between fifth generation and sealant group, and fifth generation and seventh generation groups; whereas, no significant difference was found for sealant retention between seventh generation and sealant group at three, six and 12 months. Conclusion: As separate etch and rinse steps are not required for seventh generation bonding agents, and almost similar results were obtained for both sealant and seventh generation groups, it can be concluded that application of sealant along with a seventh generation bonding agent may enhance sealant success and can be used for caries prevention in preventive programs. PMID:27252754

  11. Effect of an Antibacterial Monomer on the Antibacterial Activity of a Pit-and-Fissure Sealant

    PubMed Central

    Dong, Yan; Zhang, Ling; Sun, Xiang; Liu, Zhengya; Guo, Huihui; Huang, Li; Chen, Jihua

    2016-01-01

    Resin-based pit-and-fissure sealants are often used to form a barrier on the occlusal surface of molars to treat caries lesions; however, bacteria can remain in the pit and fissures without detection, increasing the risk of secondary caries. Sealants with antimicrobial properties or microbial repellent actions might be advantageous. The aim of this study was to assess the inhibitory effect of a 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB)-incorporated sealant against Streptococcus mutans. MAE-DB (4% wt) was incorporated into a commercially available sealant, Eco-S resin-based pit-and-fissure sealant (Vericom Co., Ltd., Korea); a sealant without MAE-DB served as a negative control, and Clinpro™ Sealant (3M™ ESPE™), a fluoride-releasing resin, was used as a commercial control. The effects of the cured sealants and their eluents on the growth of S. mutans were determined according to colony-forming unit counts and metabolic tests. The effects of the cured sealants on the adherence and membrane integrity of S. mutans were investigated using confocal laser-scanning microscopy (CLSM) in conjunction with fluorescent indicators. Compared with the negative control and commercial control, the cured MAE-DB-incorporated pit-and-fissure sealant exhibited a significant inhibitory effect on the growth of S. mutans (P < 0.05), whereas the eluents did not show any detectable antibacterial activity. The commercial control also showed no detectable bactericidal activity. Moreover, the aged experimental material retained its property of contact inhibition of biofilm formation. The fluorescence analysis of CLSM images demonstrated that the cured MAE-DB-incorporated sealant could hamper the adherence of S. mutans and exert a detrimental effect on bacterial membrane integrity. The incorporation of MAE-DB can render a pit-and-fissure sealant with contact antibacterial activity after polymerization via influencing the growth, adherence, and membrane integrity of S

  12. Bonding Agents in Pit and Fissure Sealants: A Review

    PubMed Central

    Das, Usha Mohan; G, Suma

    2009-01-01

    Dental adhesive systems used for bonding dental resins to enamel and dentin have evolved through several "generations," with changes in chemistry, mechanism, number of bottles, application technique, and clinical effectiveness. The trend in the latest generation of dental bonding systems is to reduce the number of components and clinical placement steps. The introduction of i bond, a single-bottle dental adhesive system, is the latest of the new generation materials, and combines etchant, adhesive, and desensitizer in one component. This paper describes different dentin bonding agents, its evolution, mechanism of action and different commercially available dentin bonding agents and their role in the retention of pit and fissure sealant. PMID:25206115

  13. Lytic resistance of fibrin containing red blood cells.

    PubMed

    Wohner, Nikolett; Sótonyi, Péter; Machovich, Raymund; Szabó, László; Tenekedjiev, Kiril; Silva, Marta M C G; Longstaff, Colin; Kolev, Krasimir

    2011-10-01

    Arterial thrombi contain variable amounts of red blood cells (RBCs), which interact with fibrinogen through an eptifibatide-sensitive receptor and modify the structure of fibrin. In this study, we evaluated the modulator role of RBCs in the lytic susceptibility of fibrin. If fibrin is formed at increasing RBC counts, scanning electron microscopy evidenced a decrease in fiber diameter from 150 to 96 nm at 40% (v/v) RBCs, an effect susceptible to eptifibatide inhibition (restoring 140 nm diameter). RBCs prolonged the lysis time in a homogeneous-phase fibrinolytic assay with tissue plasminogen activator (tPA) by up to 22.7±1.6%, but not in the presence of eptifibatide. Confocal laser microscopy using green fluorescent protein-labeled tPA and orange fluorescent fibrin showed that 20% to 40% (v/v) RBCs significantly slowed down the dissolution of the clots. The fluorescent tPA variant did not accumulate on the surface of fibrin containing RBCs at any cell count above 10%. The presence of RBCs in the clot suppressed the tPA-induced plasminogen activation, resulting in 45% less plasmin generated after 30 minutes of activation at 40% (v/v) RBCs. RBCs confer lytic resistance to fibrin resulting from modified fibrin structure and impaired plasminogen activation through a mechanism that involves eptifibatide-sensitive fibrinogen-RBC interactions.

  14. Modeling fibrin aggregation in blood flow with discrete-particles.

    PubMed

    Boryczko, Krzysztof; Dzwinel, Witold; Yuen, David A

    2004-09-01

    Excessive clotting can cause bleeding over a vast capillary area. We study the mesoscopic dynamics of clotting by using the fluid particle model. We assume that the plasma consists of fluid particles containing fibrin monomers, while the red blood cells and capillary walls are modeled with elastic mesh of "solid" particles. The fluid particles interact with each other with a short-ranged, repulsive dissipative force. The particles containing fibrin monomers have a dual character. The polymerization of fibrin monomers into hydrated fibrins is modeled by the change of the interactions between fluid particles from repulsive to attractive forces. This process occurs with a probability being an increasing function of the local density. We study the blood flow in microscopic capillary vessels about 100 microm long and with diameters in order of 10 microm. We show that the model of polymerization reflects clearly the role played by fibrins in clotting. Due to the density fluctuations caused the by the high acceleration, the fibrin chains are produced within a very short time (0.5 ms). Fibrin aggregation modifies the rheological properties of blood, slows down the incipient flow, and entraps the red blood cells, thus forming dangerous clots.

  15. Peptide-derivatized albumins that inhibit fibrin polymerization.

    PubMed

    Watson, Joseph W; Doolittle, Russell F

    2011-11-15

    Synthetic peptides patterned on sequences that appear during thrombin proteolysis of fibrinogen are known to influence fibrin formation in very different ways. A-Knob sequences (GPR-) inhibit polymerization, but B-knob sequences (GHR-) can actually enhance the process. We now report that when such peptides are attached to albumin carriers, both knob conjugates inhibit fibrin formation. In contrast, the 2-aminoethylthiol-albumin conjugate control enhances the polymerization to the same degree as albumin. The peptide AHRPam, which is known to bind exclusively to the βC holes of fibrinogen/fibrin, nullifies the inhibitory effects of the GHRPYGGGCam-albumin conjugate on fibrin polymerization, indicating that the inhibition was exclusively due to interactions with βC holes. AHRPam was much less effective in countering inhibition by the GPRPGGGGCam-albumin conjugate, suggesting that the observed effects with this conjugate involve mainly the γC holes of fibrin/fibrinogen. This study demonstrates that peptides modeled on fibrin polymerization knobs tethered to albumin retain their capacity to interact with fibrinogen/fibrin and may prove useful as inhibitors of clotting in vivo.

  16. Discriminating Neoantigenic Differences Between Fibrinogen and Fibrin Derivatives

    PubMed Central

    Plow, Edward F.; Edgington, Thomas S.

    1973-01-01

    Discrimination between the physiological cleavage fragments of fibrinogen and fibrin offers an approach to differentiation between fibrinogenolytic processes and fibrinolysis after coagulation. By use of the cleavage-associated neoantigen of fibrinogen (fg-Dneo) as a molecular marker, characteristic differences between the D regions of fibrinogen derivatives and fibrin derivatives can be demonstrated. The expression of fg-Dneo by X, Y, D:E complex, and D-fragments of fibrinogen or fibrin is shown to be quantitative and unitary. Characteristic differences between fg-Dneo sites present on fibrinogen cleavage fragments, as contrasted to fibrin cleavage fragments, are indicated by different competitive inhibition slopes, and appear to reflect differential binding affinity of selected anti-fg-Dneo antibodies for the specific molecular site. There is a linear relationship between the slope of quantitative competitive inhibition and the relative molar ratio of fibrinogen and fibrin derivatives. Identical immunochemical expressions are observed in vitro and in vivo, and support the thesis that cleavage in vivo is produced by plasmin. The differential immunochemical features of fg-Dneo expression may be the result of stable conformational and/or subtle structural differences between the D region of fibrinogen and fibrin cleavage fragments and suggest that precise changes in the D region are associated with the fibrin transition. These molecular features not only provide additional insight into the molecular immunology and structure of fibrinogen, but also appear to offer a new molecular approach to discrimination between fibrinogenolytic mechanisms as contrasted to fibrinolysis secondary to coagulation. PMID:4123931

  17. Role of plasma-rich fibrin in oral surgery

    PubMed Central

    Kumar, K. Retna; Genmorgan, K.; Abdul Rahman, S. M.; Rajan, M. Alaguvel; Kumar, T. Arul; Prasad, V. Srinivas

    2016-01-01

    Platelet-rich fibrin (PRF) is a fibrin meshwork, in which platelet cytokines, growth factors, and cells are entrapped and discharged after a period and can serve as a resorbable film. PRF is the next generation of platelet concentrates equipped to improve arrangement without biochemical blood handling; PRF is an evolution of the fibrin adhesive, which is widely used in the oral surgery. The guidelines of this innovation depend on concentrating platelets and growth factors in a plasma medium, and initiating them in a fibrin gel, keeping in mind the end goal to enhance the healing of wounds. Maxillary bone loss requires numerous regenerative techniques: as a supplement to the procedures of tissue regeneration, a platelet concentrate called PRF was tested for the 1st time in France by Dr. Choukroun. This article enriches the benefits and role of plasma-rich fibrin in oral surgery. Platelet-concentrate fibrin is an evolution of the fibrin glue, which is widely used in the oral surgery. PMID:27829743

  18. Patch antenna terahertz photodetectors

    SciTech Connect

    Palaferri, D.; Todorov, Y. Chen, Y. N.; Madeo, J.; Vasanelli, A.; Sirtori, C.; Li, L. H.; Davies, A. G.; Linfield, E. H.

    2015-04-20

    We report on the implementation of 5 THz quantum well photodetector exploiting a patch antenna cavity array. The benefit of our plasmonic architecture on the detector performance is assessed by comparing it with detectors made using the same quantum well absorbing region, but processed into a standard 45° polished facet mesa. Our results demonstrate a clear improvement in responsivity, polarization insensitivity, and background limited performance. Peak detectivities in excess of 5 × 10{sup 12} cmHz{sup 1/2}/W have been obtained, a value comparable with that of the best cryogenic cooled bolometers.

  19. Effect of light curing methods on microleakage and microhardness of different resin sealants.

    PubMed

    Duangthip, Duangporn; Ballungpattama, Suda; Sitthisettapong, Thanya

    2011-07-01

    This study's purpose was to evaluate the effect of light curing methods on the microleakage and microhardness of sealants. The Elipar Free Light 2 light emitting diode (LED) with 10- and 20-second curing times, and the Elipar 2500 halogen light with a 20-second curing time were compared. Four different sealants were used: (1) Delton Clear; (2) Delton Opaque; (3) UltraSeal XT Clear; and (4) UltraSeal XT Opaque. Specimens were fabricated in a silicone mold (2-mm thick) and cured. Knoop hardness was measured at the bottom and top surfaces. For the microleakage evaluation, 120 human molars were divided into 12 groups and sealed with the sealants and curing methods, as stated previously. The teeth were thermocycled and immersed in 2% methylene blue for 24 hours. Each tooth was sectioned and examined for dye penetration. There were no statistically significant differences in the microleakage of sealants polymerized by either the halogen or LED curing methods. The microhardness of sealants varied according to the type of material and curing method. A 10-second polymerization time with light emitting diodes was not sufficient to cure the 2-mm-thick opaque or high filler loaded sealants. Decreasing the curing time, however, had no effect on the microleakage of the sealants.

  20. Toxicity of coal-tar pavement sealants and ultraviolet radiation to Ambystoma Maculatum.

    PubMed

    Bommarito, Thomas; Sparling, Donald W; Halbrook, Richard S

    2010-08-01

    Polycyclic aromatic hydrocarbons (PAHs) can affect amphibians in lethal and many sublethal ways. There are many natural and anthropogenic sources of PAHs in aquatic environments. One potentially significant source is run off from surfaces of parking lots and roads that are protected with coal tar sealants. Coal tar is 50% or more PAH by wet weight and is used in emulsions to treat these surfaces. Break down of sealants can result in contamination of nearby waters. The toxicity of PAHs can be greatly altered by simultaneous exposure to ultraviolet radiation. This study exposes larvae of the spotted salamander (Ambystoma maculatum) to determine if coal tar sealant can have negative effects on aquatic amphibians and if coal tar toxicity is influenced by ultraviolet radiation. Spotted salamanders were exposed to 0, 60, 280 and 1500 mg coal tar sealant/kg sediment for 28 days. Half of the animals were exposed to conventional fluorescent lighting only and half were exposed to fluorescent lighting plus ultraviolet radiation. No significant mortality occurred during the experiment. Exposure to sealants resulted in slower rates of growth, and diminished ability to swim in a dose-dependent fashion. Exposure to ultraviolet radiation affected the frequencies of leukocytes and increased the incidence of micronucleated erythrocytes. There was an interactive effect of sealant and radiation on swimming behavior. We conclude that coal-tar sealant and ultraviolet radiation increased sublethal effects in salamanders, and may be a risk to salamanders under field conditions.

  1. Selective removal of composite sealants with near-ultraviolet laser pulses of nanosecond duration.

    PubMed

    Louie, Tiffany M; Jones, Robert S; Sarma, Anupama V; Fried, Daniel

    2005-01-01

    It is often necessary to replace pit and fissure sealants and composite restorations. This task is complicated by the necessity for complete removal of the remaining composite to enable suitable adhesion of new composite. Previous studies have shown that 355-nm laser pulses from a frequency-tripled Nd:YAG laser can selectively remove residual composite after orthodontic bracket removal on enamel surfaces. Our objective is to determine if such laser pulses are suitable for selective removal of composite pit and fissure sealants and restorations. Optical coherence tomography is used to acquire optical cross sections of the occlusal topography nondestructively before sealant application, after sealant application, and after sealant removal. Thermocouples are used to monitor the temperature in the pulp chamber during composite removal under clinically relevant ablation rates, i.e., 30 Hz and 30 mJ/pulse. At an irradiation intensity of 1.3 J/cm2, pit and fissure sealants are completely removed without visible damage to the underlying enamel. At intensities above 1.5 J/cm2, incident laser pulses remove the resin layer while at the same time preferentially etching the surface of the enamel. Temperature excursions in the pulp chamber of extracted teeth are limited to less than 5 degrees C if air-cooling is used during the rapid removal (1 to 2 min) of sealants, water-cooling is not necessary. Selective removal of composite restorative materials is possible without damage to the underlying sound tooth structure.

  2. Oral Contraceptives and Increased Formation of Soluble Fibrin

    PubMed Central

    Pilgeram, L. O.; Ellison, J.; Bussche, G. Von Dem

    1974-01-01

    Soluble fibrin was measured weekly for two months in 12 normal women and in 12 women on combined oestrogen-progestogen therapy (Ortho-Novin, Norinyl, Enavid, Ovral, Ovulen, Demulen). Plasma soluble fibrin concentration in women on oral contraceptives showed an increase of 97·2% (P <0·001) above that of normal women. In three cases, where each woman on the oral contraceptive served as her own control, stopping medication led to a return to normal of the plasma content of soluble fibrin. PMID:4414937

  3. Interactions between ultrasound stimulated microbubbles and fibrin clots

    NASA Astrophysics Data System (ADS)

    Acconcia, Christopher; Leung, Ben Y. C.; Hynynen, Kullervo; Goertz, David E.

    2013-07-01

    While it is well established that ultrasound stimulated microbubbles (USMBs) can potentiate blood clot lysis, the mechanisms are not well understood. Here we examine the interaction between USMBs and fibrin clots, which are comprised of fibrin networks that maintain the mechanical integrity of blood clots. High speed camera observations demonstrated that USMBs can penetrate fibrin clots. Two-photon microscopy revealed that penetrating bubbles can leave behind patent "tunnels" along their paths and that fluid can be transported into the clots. Finally, it is observed that primary radiation forces associated with USMBs can induce local deformation and macroscopic translation of clot boundaries.

  4. Fluoride: Is It Worth to be added in Pit and Fissure Sealants?

    PubMed Central

    Dahake, Prasanna T; Raju, OS; Basappa, N

    2012-01-01

    ABSTRACT Background and objectives: Fluoride is being used for the prevention of dental caries since a long time. Incorporation of fluoride in pit and fissure sealants has been found to reduce initiation and progression of pit and fissure caries. Authors conducted this study to evaluate and compare the effect of fluoride releasing pit and fissure sealants on the inhibition of demineralization of adjacent enamel and to reduce wall lesion frequency. Materials and methods: A total of 60 caries-free human third molars were randomly assigned into three groups receiving conventional resin sealant without fluoride (Group A), fluoride releasing resin sealant (Group B), glass ionomer pit and fissure sealant (Group C). Fissure cavities of 5 × 2 × 1.5 mm were prepared on buccal surfaces of teeth using fissurotomy bur and sealants were applied onto the cavities. The teeth were then thermocycled and exposed to acidified gelatin gel for 6 weeks to induce caries like lesions. A 150 μ m section was taken from each tooth and observed under polarized light microscope to measure the depth of advancing front of outer enamel lesion. The outer lesion depths of all three groups were compared. Results: Enamel demineralization was least in glass ionomer pit and fissure sealant while the demineralization exhibited by nonfluoridated resin and fluoridated resin were comparable. Wall lesion frequency was found to be 0% in all groups. Conclusion and interpretation: The glass ionomer pit and fissure sealant exhibited highest anticariogenic efficacy and hence can be advocated as a means of preventing dental caries. How to cite this article: Prabhakar AR, Dahake PT, Raju OS, Basappa N. Fluoride: Is It Worth to be added in Pit and Fissure Sealants?. Int J Clin Pediatr Dent 2012;5(1):1-5. PMID:25206126

  5. A 48-month clinical evaluation of fissure sealants placed with different adhesive systems.

    PubMed

    Karaman, E; Yazici, A R; Tuncer, D; Firat, E; Unluer, S; Baseren, M

    2013-01-01

    To compare the retention rates of a nanofilled occlusal fissure sealant placed with the use of an etch-and-rinse or a self-etch adhesive over 48 months. The authors enrolled 244 teeth, each with no restoration or sealant and no detectable caries, from 16 patients. The sealants were placed with Solobond M two-step etch-and-rinse adhesive or Futurabond NR one-step self-etch adhesive by four previously calibrated dentists using a table of random numbers. After completion of the adhesive application, a nanofilled sealant, Grandio Seal, was applied and light-cured. Two other calibrated examiners, who were unaware of which adhesive had been used, independently evaluated the sealants at baseline and at 12-, 24-, 36-, and 48-month recalls. Each sealant was evaluated in terms of caries formation being present or absent and retention using the following criteria: 1 = completely retained, 2 = partial loss, and 3 = total loss. The Pearson χ (2) test was used to evaluate differences in retention rates among the sealants used with different adhesives for each evaluation period. The retention rates for sealants in the Solobond M group were significantly higher than those in the Futurabond NR group in all periods of evaluation (p<0.05). No statistically significant difference between the retention rates for premolars and molars was found at each evaluation period (p>0.05). There was no new caries formation throughout the 48-month recall period. Fissure sealants placed with etch-and-rinse adhesive showed better retention rates than those placed with self-etch adhesive.

  6. Retention of resin-based filled and unfilled pit and fissure sealants: A comparative clinical study.

    PubMed

    Reddy, V Rajashekar; Chowdhary, Nagalakshmi; Mukunda, K S; Kiran, N K; Kavyarani, B S; Pradeep, M C

    2015-03-01

    The most caries-susceptible period of a permanent first molar tooth is the eruption phase, during which the enamel is not fully matured and it is usually difficult for the child to clean the erupting tooth surfaces. Sealing occlusal pits and fissures with resin-based pit and fissure sealants is a proven method to prevent occlusal caries. The difference in the viscosity of the sealants differs in the penetration into pit and fissures and abrasive wear resistance property due to the addition of filler particles. The present study was conducted to evaluate and compare the retention of the resin-based filled (Helioseal F, Ivoclar Vivadent) and unfilled (Clinpro, 3M ESPE) pit and fissure sealants, which is important for their effectiveness. Fifty-six children between the age group of 6 and 9 years, with all four newly erupted permanent first molars were selected. Sealants were applied randomly using split mouth design technique on permanent first molars. Evaluation of sealant retention was performed at regular intervals over 12 months, using Simonsen's criteria at 2(nd), 4(th), 6(th), 8(th), 10(th) and 12(th) month. The results were subjected to statistical analysis. At the end of our study period (12(th) month), 53.57% showed complete retention, 37.50% showed partial retention, and 8.83% showed complete missing of resin-based filled (Helioseal F) pit and fissure sealant. And, 64.29% showed complete retention, 32.14% showed partial retention, and 3.57% showed complete missing of resin-based unfilled (Clinpro) pit and fissure sealant. This difference in retention rates between filled and unfilled pit and fissure sealants was not statistically significant. The difference in retention rates between Helioseal F and Clinpro was not statistically significant, but Clinpro (unfilled) sealant showed slightly higher retention rates and clinically better performance than Helioseal F (filled).

  7. Caries-preventive effect of sealants produced with altered glass-ionomer materials, after 2 years.

    PubMed

    Chen, X; Du, M Q; Fan, M W; Mulder, J; Huysmans, M C D N J M; Frencken, J E

    2012-05-01

    The aim of the present study was to investigate the caries-preventive effect of sealants produced with a high-viscosity glass-ionomer with an elevated powder-liquid ratio (ART), of having energy added to this glass-ionomer, and that of glass-carbomer, in comparison to that of resin composite sealants. The randomized controlled trial covered 407 children, with a mean age of 8 years. At a school compound three dentists placed sealants in pits and fissures of high caries-risk children. Evaluation by two independent evaluators was conducted after 0.5, 1 and 2 years. The Kaplan-Meier survival method, ANOVA and t-test were used in analyzing the data. 1352 first permanent molars were sealed. 6.6% of children and 6.8% of sealants dropped out within 2 years. 27 re-exposed pits and fissures, 20 in occlusal and 7 in smooth surfaces, in 25 children, developed a dentin carious lesion. The cumulative survival of dentin carious lesion-free pits and fissures in the glass-carbomer sealant group was statistically significantly lower (97.4%) than those in the high-viscosity glass-ionomer with energy supplied (99%) and the resin-composite (98.9%) sealant groups. There was no statistically significant difference in the cumulative survival of dentin carious lesion-free pits and fissures, between the high-viscosity glass-ionomer with (99%) and without (98.3%) energy supplied sealant groups, after 2 years. The survival of dentin carious lesion-free pits and fissures was high in all sealant types. More dentin carious lesions were observed in the glass-carbomer sealant group. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  8. Retention of resin-based filled and unfilled pit and fissure sealants: A comparative clinical study

    PubMed Central

    Reddy, V. Rajashekar; Chowdhary, Nagalakshmi; Mukunda, K. S.; Kiran, N. K.; Kavyarani, B. S.; Pradeep, M. C.

    2015-01-01

    Background and Objectives: The most caries-susceptible period of a permanent first molar tooth is the eruption phase, during which the enamel is not fully matured and it is usually difficult for the child to clean the erupting tooth surfaces. Sealing occlusal pits and fissures with resin-based pit and fissure sealants is a proven method to prevent occlusal caries. The difference in the viscosity of the sealants differs in the penetration into pit and fissures and abrasive wear resistance property due to the addition of filler particles. The present study was conducted to evaluate and compare the retention of the resin-based filled (Helioseal F, Ivoclar Vivadent) and unfilled (Clinpro, 3M ESPE) pit and fissure sealants, which is important for their effectiveness. Materials and Methods: Fifty-six children between the age group of 6 and 9 years, with all four newly erupted permanent first molars were selected. Sealants were applied randomly using split mouth design technique on permanent first molars. Evaluation of sealant retention was performed at regular intervals over 12 months, using Simonsen's criteria at 2nd, 4th, 6th, 8th, 10th and 12th month. The results were subjected to statistical analysis. Results: At the end of our study period (12th month), 53.57% showed complete retention, 37.50% showed partial retention, and 8.83% showed complete missing of resin-based filled (Helioseal F) pit and fissure sealant. And, 64.29% showed complete retention, 32.14% showed partial retention, and 3.57% showed complete missing of resin-based unfilled (Clinpro) pit and fissure sealant. This difference in retention rates between filled and unfilled pit and fissure sealants was not statistically significant. Conclusion: The difference in retention rates between Helioseal F and Clinpro was not statistically significant, but Clinpro (unfilled) sealant showed slightly higher retention rates and clinically better performance than Helioseal F (filled). PMID:25821368

  9. Microleakage of two fluoride-releasing sealants when applied following saliva contamination.

    PubMed

    Rirattanapong, Praphasri; Vongsavan, Kadkao; Surarit, Rudee

    2013-09-01

    The purpose of this in vitro study was to evaluate microleakage of two fluoride-releasing sealants in saliva contaminated and non-contaminated conditions. Twenty-four human third molars were randomly assigned to two groups: saliva contaminated and saliva non-contaminated teeth. In the contaminated group, the teeth were contaminated with 0.02 ml artificial saliva for 20 seconds and blowed dry afterward. Each group was divided into two subgroups: Group A, a fluoride-releasing resin sealant marketed as Clinpro and Group B, a glass-ionomer sealant marketed as Fuji VII. After sealant application, all the teeth were thermocycled for 2,000 cycles and coated with nail varnish 1.0 mm from the sealed areas. The teeth were stained with 2% methylene blue dye for 24 hours and sectioned in the bucco-lingual direction. Dye penetration (microleakage) was examined with a 25x polarized light microscope and measured by a computerized-calculated method. Data were compared with the Mann-Whitney U test at significance level of p<0.05. A comparison of the two types of sealant revealed microleakage of the glass-ionomer sealant was present but there was no significant difference between the saliva contaminated and saliva non-contaminated teeth. Microleakage of the fluoride-releasing resin sealant was present and was greater among the saliva-contaminated teeth than the saliva non-contaminated teeth. The glass-ionomer sealant had significantly greater microleakage than the fluoride-relasing resin-based sealant in both the saliva-contaminated and saliva non-contaminated teeth.

  10. Expedition 17 Patch

    NASA Image and Video Library

    2007-08-01

    ISS017-S-001B (Oct. 2007) --- The Expedition 17 patch is meant to celebrate current human achievements in space as well as symbolize the future potential for continuing exploration. The Earth, represented at the bottom of the patch, is the base from which all space exploration activities initiate. The International Space Station (ISS), shown in low Earth orbit, illustrates the current level of space operations. The arrow and star point outwards, away from the Earth, towards the wider universe indicating the direction of future activities as human beings build on what has already been accomplished. The flags, representing the home countries of the crew members, Russia and the United States, are touching, highlighting the cooperative nature of the space program and symbolizing the merger of science and technical knowledge of these two experienced space-faring nations. The NASA insignia design for space station flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, it will be publicly announced.

  11. Expedition 17 Patch

    NASA Image and Video Library

    2007-10-01

    ISS017-S-001D (Oct. 2007) --- The Expedition 17 patch is meant to celebrate current human achievements in space as well as symbolize the future potential for continuing exploration. The Earth, represented at the bottom of the patch, is the base from which all space exploration activities initiate. The International Space Station (ISS), shown in low Earth orbit, illustrates the current level of space operations. The arrow and star point outwards, away from the Earth, towards the wider universe indicating the direction of future activities as human beings build on what has already been accomplished. The flags, representing the home countries of the crew members, Russia and the United States, are touching, highlighting the cooperative nature of the space program and symbolizing the merger of science and technical knowledge of these two experienced space-faring nations. The NASA insignia design for space station flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, it will be publicly announced.

  12. Expedition 17 Patch

    NASA Image and Video Library

    2007-10-01

    ISS017-S-001C (Oct. 2007) --- The Expedition 17 patch is meant to celebrate current human achievements in space as well as symbolize the future potential for continuing exploration. The Earth, represented at the bottom of the patch, is the base from which all space exploration activities initiate. The International Space Station (ISS), shown in low Earth orbit, illustrates the current level of space operations. The arrow and star point outwards, away from the Earth, towards the wider universe indicating the direction of future activities as human beings build on what has already been accomplished. The flags, representing the home countries of the crew members, Russia and the United States, are touching, highlighting the cooperative nature of the space program and symbolizing the merger of science and technical knowledge of these two experienced space-faring nations. The NASA insignia design for space station flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, it will be publicly announced.

  13. Patched Conic Trajectory Code

    NASA Technical Reports Server (NTRS)

    Park, Brooke Anderson; Wright, Henry

    2012-01-01

    PatCon code was developed to help mission designers run trade studies on launch and arrival times for any given planet. Initially developed in Fortran, the required inputs included launch date, arrival date, and other orbital parameters of the launch planet and arrival planets at the given dates. These parameters include the position of the planets, the eccentricity, semi-major axes, argument of periapsis, ascending node, and inclination of the planets. With these inputs, a patched conic approximation is used to determine the trajectory. The patched conic approximation divides the planetary mission into three parts: (1) the departure phase, in which the two relevant bodies are Earth and the spacecraft, and where the trajectory is a departure hyperbola with Earth at the focus; (2) the cruise phase, in which the two bodies are the Sun and the spacecraft, and where the trajectory is a transfer ellipse with the Sun at the focus; and (3) the arrival phase, in which the two bodies are the target planet and the spacecraft, where the trajectory is an arrival hyperbola with the planet as the focus.

  14. STS-62 crew patch

    NASA Image and Video Library

    1993-10-01

    STS062-S-001 (October 1993) --- The crew patch depicts the world's first reusable spacecraft on its sixteenth flight. The space shuttle Columbia is in its entry-interface attitude as it prepares to return to Earth. The primary mission objectives of STS-62 include the United States Microgravity Payload (USMP-2) and the NASA Office of Aeronautics and Space Technology (OAST-2) payloads. These payloads represent a multifaceted array of space science and engineering experiments. The varied hues of the rainbow on the horizon connote the varied, but complementary, nature of all the payloads united on this mission. The upward-pointing vector shape of the patch is symbolic of America's reach for excellence in its in its unswerving pursuit to explore the frontiers of space. The brilliant sunrise just beyond Columbia suggests the promise that research in space holds for the hopes and dreams of future generations. The STS-62 insignia was designed by Mark Pestana. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

  15. Tiling motion patches.

    PubMed

    Hyun, Kyunglyul; Kim, Manmyung; Hwang, Youngseok; Lee, Jehee

    2013-11-01

    Simulating multiple character interaction is challenging because character actions must be carefully coordinated to align their spatial locations and synchronized with each other. We present an algorithm to create a dense crowd of virtual characters interacting with each other. The interaction may involve physical contacts, such as hand shaking, hugging, and carrying a heavy object collaboratively. We address the problem by collecting deformable motion patches, each of which describes an episode of multiple interacting characters, and tiling them spatially and temporally. The tiling of motion patches generates a seamless simulation of virtual characters interacting with each other in a nontrivial manner. Our tiling algorithm uses a combination of stochastic sampling and deterministic search to address the discrete and continuous aspects of the tiling problem. Our tiling algorithm made it possible to automatically generate highly complex animation of multiple interacting characters. We achieve the level of interaction complexity far beyond the current state of the art that animation techniques could generate, in terms of the diversity of human behaviors and the spatial/temporal density of interpersonal interactions.

  16. Tiling Motion Patches.

    PubMed

    Hyun, Kyunglyul; Kim, Manmyung; Hwang, Youngseok; Lee, Jehee

    2013-05-08

    Simulating multiple character interaction is challenging because character actions must be carefully coordinated to align their spatial locations and synchronized with each other. We present an algorithm to create a dense crowd of virtual characters interacting with each other. The interaction may involve physical contacts, such as hand shaking, hugging, and carrying a heavy object collaboratively. We address the problem by collecting deformable motion patches, each of which describes an episode of multiple interacting characters, and tiling them spatially and temporally. The tiling of motion patches generates a seamless simulation of virtual characters interacting with each other in a non-trivial manner. Our tiling algorithm uses a combination of stochastic sampling and deterministic search to address the discrete and continuous aspects of the tiling problem. Our tiling algorithm made it possible to automatically generate highly-complex animation of multiple interacting characters. We achieved the level of complexity far beyond the current state-of-the-art animation techniques could generate, in terms of the diversity of human behaviors and the spatial/temporal density of interpersonal interactions.

  17. Expedition 13 crew patch

    NASA Image and Video Library

    2006-01-01

    ISS013-S-001 (January 2006) --- This patch commemorates the thirteenth expeditionary mission to the International Space Station (ISS) which continues the permanent human presence in space. The ISS is depicted in its configuration at the start of the six-month expedition with trailing elements from the country flags representing both of the crew members--cosmonaut Pavel V. Vinogradov and astronaut Jeffrey N. Williams. The crew members made the following statement about their patch: "The dynamic trajectory of the space station against the background of the Earth, Mars, and the Moon symbolizes the vision for human space exploration beyond Earth orbit and the critical role that the ISS plays in the fulfillment of that vision." The NASA insignia design for shuttle flights and station increments is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced.

  18. STS-128 patch Pathd

    NASA Image and Video Library

    2009-04-14

    STS128-S-001 (April 2009) --- The STS-128 patch symbolizes the 17A mission and represents the hardware, people and partner nations that contribute to the flight. The Space shuttle Discovery is shown in the orbit configuration with the Multi-Purpose Logistics Module (MPLM) Leonardo in the payload bay. Earth and the International Space Station wrap around the Astronaut Office symbol reminding us of the continuous human presence in space. The names of the STS-128 crew members border the patch in an unfurled manner. Included in the names is the expedition crew member who will launch on STS-128 and remain on board ISS, replacing another Expedition crew member who will return home with STS-128. The banner also completes the Astronaut Office symbol and contains the U.S. and Swedish flags representing the countries of the STS-128 crew. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

  19. Statistics for Patch Observations

    NASA Astrophysics Data System (ADS)

    Hingee, K. L.

    2016-06-01

    In the application of remote sensing it is common to investigate processes that generate patches of material. This is especially true when using categorical land cover or land use maps. Here we view some existing tools, landscape pattern indices (LPI), as non-parametric estimators of random closed sets (RACS). This RACS framework enables LPIs to be studied rigorously. A RACS is any random process that generates a closed set, which encompasses any processes that result in binary (two-class) land cover maps. RACS theory, and methods in the underlying field of stochastic geometry, are particularly well suited to high-resolution remote sensing where objects extend across tens of pixels, and the shapes and orientations of patches are symptomatic of underlying processes. For some LPI this field already contains variance information and border correction techniques. After introducing RACS theory we discuss the core area LPI in detail. It is closely related to the spherical contact distribution leading to conditional variants, a new version of contagion, variance information and multiple border-corrected estimators. We demonstrate some of these findings on high resolution tree canopy data.

  20. Chemically bonded phosphate ceramic sealant formulations for oil field applications

    SciTech Connect

    Wagh, Arun S.; Jeong, Seung-Young; McDaniel, Richard

    2008-10-21

    A sealant for an oil or geothermal well capable of setting within about 3 to about 6 hours at temperatures less than about 250.degree. F. for shallow wells less than about 10,000 feet and deep wells greater than about 10,000 feet having MgO present in the range of from about 9.9 to about 14.5%, KH.sub.2PO.sub.4 present in the range of from about 29.7 to about 27.2%, class C fly ash present in the range of from about 19.8 to about 36.3%, class F fly ash present in the range of from about 19.8 to about 0%, boric acid or borax present in the range of from about 0.39 to about 1.45%, and water present in the range of from about 20.3 to about 21.86% by weight of the sealant.A method of sealing wells is disclosed as are compositions for very high temperature wells is disclosed as is a composition for treating oil field wastes.

  1. Dystrophic heart failure blocked by membrane sealant poloxamer

    NASA Astrophysics Data System (ADS)

    Yasuda, Soichiro; Townsend, Dewayne; Michele, Daniel E.; Favre, Elizabeth G.; Day, Sharlene M.; Metzger, Joseph M.

    2005-08-01

    Dystrophin deficiency causes Duchenne muscular dystrophy (DMD) in humans, an inherited and progressive disease of striated muscle deterioration that frequently involves pronounced cardiomyopathy. Heart failure is the second leading cause of fatalities in DMD. Progress towards defining the molecular basis of disease in DMD has mostly come from studies on skeletal muscle, with comparatively little attention directed to cardiac muscle. The pathophysiological mechanisms involved in cardiac myocytes may differ significantly from skeletal myofibres; this is underscored by the presence of significant cardiac disease in patients with truncated or reduced levels of dystrophin but without skeletal muscle disease. Here we show that intact, isolated dystrophin-deficient cardiac myocytes have reduced compliance and increased susceptibility to stretch-mediated calcium overload, leading to cell contracture and death, and that application of the membrane sealant poloxamer 188 corrects these defects in vitro. In vivo administration of poloxamer 188 to dystrophic mice instantly improved ventricular geometry and blocked the development of acute cardiac failure during a dobutamine-mediated stress protocol. Once issues relating to optimal dosing and long-term effects of poloxamer 188 in humans have been resolved, chemical-based membrane sealants could represent a new therapeutic approach for preventing or reversing the progression of cardiomyopathy and heart failure in muscular dystrophy.

  2. Reinforced composite sealants for solid oxide fuel cell applications

    NASA Astrophysics Data System (ADS)

    Gross, Sonja M.; Federmann, Dirk; Remmel, Josef; Pap, Michael

    Glass-ceramic sealants are commonly used as joining materials for planar solid oxide fuel cells stacks. Several requirements need to be fulfilled by these materials: beside of electrical insulation and appropriate thermal expansion, a good adhesion on the ceramic and metallic components of a SOFC stack is necessary to form a gas-tight joint. Even though the joining process might have been successful, failures and leaks often occur during the stack operation due to fracture of the brittle material under thermal stresses or during thermal cycling of the components. This study focusses on composite materials consisting of a glass matrix based on the system of BaO-CaO-SiO 2 and various filler materials, e.g. yttria-stabilized zirconia fibres or particles and silver particles. In order to evaluate a possible reinforcing influence of the filler material of the composite, tensile strength tests were carried out on circular butt joints. The highest strength values were found for the composite material with addition of silver particles, followed by the glass matrix itself without any filler addition and the lowest values were measured for the composite with YSZ particles. SEM investigations of cross-sections of the joints elucidated these results by the microstructure of the glass-ceramic sealants.

  3. Stopping duct quacks: Longevity of residential duct sealants

    SciTech Connect

    Sherman, Max H.; Walker, Iain S.; Dickerhoff, Darryl J.

    2000-08-01

    Duct leakage has been identified as a major source of energy loss in residential buildings. Most duct leakage occurs at the connections to registers, plenums or branches in the duct system. At each of these connections a method of sealing the duct system is required. Typical sealing methods include tapes or mastics applied around the joints in the system. Field examinations of duct systems have shown that these seals tend to fail over time periods ranging from days to years. We have used several test methods over the last few years to evaluate the longevity of duct sealants when subjected to temperatures and pressures representative of those found in the field. Traditional cloth duct tapes have been found to significantly under-perform other sealants and have been banned from receiving duct tightness credits in California's energy code (California Energy Commission 1998). Our accelerated testing apparatus has been redesigned since its first usage for improved performance. The methodology is currently under consideration by the American Society for Testing and Materials (ASTM) as a potential new test method. This report will summarize the set of measurements to date, review the status of the test apparatus and test method, and summarize the applications of these results to codes and standards.

  4. Indications for fissure sealants and their role in children and adolescents.

    PubMed

    Mejàre, Ingegerd

    2011-12-01

    The aim of this article is to summarize and interpret present knowledge and evidence on the effect of fissure sealing permanent first and second molars in children and adolescents with two commonly used materials: resin sealants and glass ionomer sealants. Also, to identify important gaps in our knowledge. The results show that the conclusions from systematic reviews differ in several aspects, and that important knowledge gaps still exist, such as the costs and benefits of sealing low- versus high-risk populations. The effect of sealing noncavitated caries lesions is uncertain and possible differences in effect between resin sealants and the high viscosity glass ionomers need to be investigated.

  5. Improved Gain Microstrip Patch Antenna

    DTIC Science & Technology

    2015-08-06

    08-2015 Publication Improved Gain Microstrip Patch Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L...Distribution A An antenna for mounting on a ground plane includes a dielectric substrate for mounting on the ground plane. A conductive patch...GAIN MICROSTRIP PATCH ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by or for the

  6. STS-102 Crew Patch

    NASA Image and Video Library

    2001-04-24

    STS102-S-001 (January 2001) --- The central image on the STS-102 crew patch depicts the International Space Station (ISS) in the build configuration that it will have at the time of the arrival and docking of Discovery during the STS-102 mission, the first crew exchange flight to the space station. The station is shown along the direction of the flight as will be seen by the shuttle crew during their final approach and docking, the so-called V-bar approach. The names of the shuttle crew members are depicted in gold around the top of the patch, and surnames of the Expedition crew members being exchanged are shown in the lower banner. The three ribbons swirling up to and around the station signify the rotation of these ISS crew members. The number two is for the Expedition Two crew who fly up to the station, and the number one is for the Expedition One crew who then return down to Earth. In conjunction with the face of the Lab module of the station, these Expedition numbers create the shuttle mission number 102. Shown mated below the ISS is the Italian-built Multi-Purpose Logistics Module, Leonardo, that will fly for the first time on this flight, and which will be attached to the station by the shuttle crew during the docked phase of the mission. The flags of the countries that are the major contributors to this effort, the United States, Russia, and Italy are also shown in the lower part of the patch. The build-sequence number of this flight in the overall station assembly sequence, 5A.1, is captured by the constellations in the background. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

  7. A randomised clinical trial on the use of intermediate bonding on the retention of fissure sealants in children.

    PubMed

    McCafferty, Jennifer; O'Connell, Anne C

    2016-03-01

    To assess whether an adhesive bonding agent increases the retention of resin fissure sealants on first permanent molars (FPMs) and to determine any difference in sealant retention on occlusal, buccal, or palatal surfaces. The effect of the child's behaviour on the retention of the sealants was also assessed. One hundred and twelve children were recruited (age range 5-15 years). One operator placed sealants (Helioseal, Ivoclar Vivadent) on 390 FPMs using a split-mouth design. The study group, (n = 195), had an ethanol-based adhesive bond (ExciTEF, Ivoclar Vivadent) placed prior to sealant application, and no bond was used in the control group (n = 195). The sealants were reviewed after 12 months and analysed using Fisher's exact test. The addition of a bonding agent significantly increased sealant retention (P = 0.0005). Retention of bonded sealants on occlusal surfaces was higher (98%) than non-bonded sealants (93%) (P = 0.08). Bonded sealants placed on buccal/palatal surfaces were retained (92%) more successfully than non-bonded sealants (82%) (P = 0.0005). The behaviour of the patient significantly affected the retention of fissure sealants (P = 0.0001). The addition of an ethanol-based bonding agent significantly increased the retention of sealants at 12 months particularly on palatal fissures of maxillary first permanent molar teeth. © 2015 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Effect of One Percent Chlorhexidine Addition on the Antibacterial Activity and Mechanical Properties of Sealants: An in vitro Study.

    PubMed

    Shanmugaavel, Arunachalam Karthikeyan; Asokan, Sharath; John, J Baby; Priya, Pr Geetha; Devi, Jagadeesan Gnana

    2015-01-01

    The aim of the study was to evaluate the effect of addition of 1% chlorhexidine digluconate solution on the antibacterial activity and mechanical properties of glass ionomer and resin based sealant. Conventional glass ionomer sealant (GIS) (Fuji VII, Japan) and resin sealant (Clinpro 3M ESPE, USA) were used in this study. Chlorhexidine digluconate (CHX) (20%) liquid was added to both the sealants, and the concentration of chlorhexidine in sealants was adjusted to 1%. The sealants were divided into four groups as: group A (GIS), group B (GIS + 1% CHX), group C (resin sealant), group D (resin sealant + 1% CHX). Five cylindrical specimens were prepared in each group. Their antibacterial activity against Streptococcus mutans and Lactobacillus acidophilus, and their mechanical properties (compressive strength and diametrical tensile strength) were assessed. Mann-Whitney and Wilcoxon signed rank test were used appropriately for statistical analysis (SPSS version 19). Addition of one percent chlorhexidine significantly increased the antibacterial activity of both the sealants. There was a significant difference between groups A and B (p < 0.009), and groups C and D (p < 0.008). There was no significant difference in the mechanical properties of the sealants. Addition of one percent chlorhexidine to the glass ionomer and resin based sealants provided sufficient antibacterial activity, without significantly affecting the mechanical property of the sealants. How to cite this article: Shanmugaavel AK, Asokan S, John JB, Geetha Priya PR, Gnana Devi J. Effect of one percent Chlorhexidine Addition on the Antibacterial Activity and Mechanical Properties of Sealants: An in vitro Study. Int J Clin Pediatr Dent 2015;8(3):196-201.

  9. Effect of One Percent Chlorhexidine Addition on the Antibacterial Activity and Mechanical Properties of Sealants: An in vitro Study

    PubMed Central

    Asokan, Sharath; John, J Baby; Priya, PR Geetha; Devi, Jagadeesan Gnana

    2015-01-01

    ABSTRACT Aim: The aim of the study was to evaluate the effect of addition of 1% chlorhexidine digluconate solution on the antibacterial activity and mechanical properties of glass ionomer and resin based sealant. Materials and methods: Conventional glass ionomer sealant (GIS) (Fuji VII, Japan) and resin sealant (Clinpro 3M ESPE, USA) were used in this study. Chlorhexidine digluconate (CHX) (20%) liquid was added to both the sealants, and the concentration of chlorhexidine in sealants was adjusted to 1%. The sealants were divided into four groups as: group A (GIS), group B (GIS + 1% CHX), group C (resin sealant), group D (resin sealant + 1% CHX). Five cylindrical specimens were prepared in each group. Their antibacterial activity against Streptococcus mutans and Lactobacillus acidophilus, and their mechanical properties (compressive strength and diametrical tensile strength) were assessed. Mann-Whitney and Wilcoxon signed rank test were used appropriately for statistical analysis (SPSS version 19). Result: Addition of one percent chlorhexidine significantly increased the antibacterial activity of both the sealants. There was a significant difference between groups A and B (p < 0.009), and groups C and D (p < 0.008). There was no significant difference in the mechanical properties of the sealants. Conclusion: Addition of one percent chlorhexidine to the glass ionomer and resin based sealants provided sufficient antibacterial activity, without significantly affecting the mechanical property of the sealants. How to cite this article: Shanmugaavel AK, Asokan S, John JB, Geetha Priya PR, Gnana Devi J. Effect of one percent Chlorhexidine Addition on the Antibacterial Activity and Mechanical Properties of Sealants: An in vitro Study. Int J Clin Pediatr Dent 2015;8(3):196-201. PMID:26628854

  10. Endothelial fibrinolytic response onto an evolving matrix of fibrin.

    PubMed

    Castillo, O; Rojas, H; Domínguez, Z; Anglés-Cano, E; Marchi, R

    2016-01-01

    Fibrin provides a temporary matrix at the site of vascular injury. The aims of the present work were (1) to follow fibrin formation and lysis onto the surface of human dermal microvascular endothelial cells (HMEC-1), and (2) to quantify the secretion of fibrinolytic components in the presence of fibrin. Fibrin clots at different fibrinogen concentrations were formed on top of (model 1) or beneath (model 2) the endothelial cells. Fibrin formation or lysis onto the surface of HMEC-1 cells, was followed by turbidity. Clot structure was visualized by laser scanning confocal microscopy (LSCM). The secretion of uPA and PAI-1 by HMEC-1 cells was quantified by ELISA. The rate of fibrin formation increased approximately 1.5-fold at low fibrinogen content (0.5 and 1 mg/mL; p < 0.05) compared to the condition without cells; however, it was decreased at 2 mg/mL fibrinogen (p < 0.05) and no differences were found at higher fibrinogen concentrations (3 and 5 mg/mL). HMEC-1 retarded dissolution of clots formed onto their surface at 0.5 to 3 mg/mL fibrinogen (p < 0.05). Secretion of uPA was 13 × 10(-6) ng/mL per cell in the absence of RGD and 8 × 10(-6) ng/mL per cell in the presence of RGD, when clots were formed on the top of HMEC-1. However, the opposite was found when cells were grown over fibrin: 6 × 10(-6) ng/mL per cell without RGD vs. 17 × 10(-6) ng/mL per cell with RGD. The secretion of PAI-1 by HMEC-1 cells was unrelated to the presence of fibrin or RGD, 7 × 10(-6) μg/mL per cell and 5 × 10(-6) μg/mL per cell, for the apical (model 1) and basal clots (model 2), respectively. HMEC-1 cells influence fibrin formation and dissolution as a function of the fibrin content of clots. Clot degradation was accentuated at high fibrin concentrations. The secretion of fibrinolytic components by HMEC-1 cells seemed to be modulated by integrins that bind RGD ligands.

  11. Expedition Seven patch

    NASA Image and Video Library

    2003-03-01

    ISS007-S-001 (March 2003) --- The International Space Station (ISS) Expedition Seven patch consists of two elliptical orbits which evoke the histories of the two space programs from which the crew is drawn. The Russian and American flags are intersecting, representing the peaceful cooperation of the many countries contributing to the ISS. Two stars indicate the station's goals of contributing to life on Earth through science and commerce. The NASA insignia design for station space flights is reserved for use by the crew members and other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, such will be publicly announced.

  12. Expedition 10 patch

    NASA Image and Video Library

    2004-05-01

    ISS010-S-001 (May 2004) --- The Expedition 10 patch uses simple symbolism to describe the mission. The large Roman numeral "X," formed by the American and Russian flags, symbolizes the joint nature of this mission, as well as the fact that this flight is the 10th mission to stay on the International Space Station (ISS). The current configuration of the ISS is next to the name of the ISS Commander, while the Soyuz vehicle is placed next to the name of the Soyuz Commander. The single star and the black background signify this is a space mission. The NASA insignia design for shuttle flights and station increments is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced.

  13. sts-135patch only

    NASA Image and Video Library

    2011-01-25

    STS135-S-001 (27 Jan. 2011) --- The STS-135 patch represents the space shuttle Atlantis embarking on its mission to resupply the International Space Station. Atlantis is centered over elements of the NASA emblem depicting how the space shuttle has been at the heart of NASA for the last 30 years. It also pays tribute to the entire NASA and contractor team that made possible all the incredible accomplishments of the space shuttle. Omega, the last letter in the Greek alphabet, recognizes this mission as the last flight of the Space Shuttle Program. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

  14. Acute Fibrinous and Organizing Pneumonia Following Hematopoietic Stem Cell Transplantation

    PubMed Central

    Lee, Sang Min; Park, Jae-Jung; Sung, Sun Hee; Kim, Yookyung; Lee, Kyoung Eun; Lee, Soon Nam; Seong, Chu Myong

    2009-01-01

    A 60-year-old man presented with cough, sputum, and dyspnea. He had a history of acute myeloid leukemia and hematopoietic stem cell transplantation with chronic renal failure. Chest CT scans showed miliary nodules and patchy consolidations. Histological examination revealed numerous fibrin balls within the alveoli and thickening of the alveolar septum, both of which are typical pathological features of acute fibrinous and organizing pneumonia (AFOP). We report the first case of AFOP following allogeneic hematopoietic stem cell transplantation. PMID:19543497

  15. Prevention of growth arrest by fibrin interposition into physeal injury.

    PubMed

    Jie, Qiang; Hu, Yunyu; Yang, Liu; Lei, Wei; Zhao, Li; Lv, Rong; Wang, Jun

    2010-03-01

    This study investigated the repair effects of fat and fibrin graft interposition through a proximal tibia transphyseal injury model and assessed the effectiveness of treatment to physeal injury with the fibrin. In this study, a unilateral growth plate injury was created in the right proximal tibia of 28 rats without any graft interposition; all left tibias were left untouched. In the other group of 28 rats, a bilateral physeal injury was made with the left tibia filled with autogenously adipose tissue and the right tibia filled with fibrin. To compare the malformed extents induced by different interventions, the length and the metaphyseal-diaphyseal angle of the tibia of three injured groups were examined. Further studies on bone density analysis and histological change were used to compare the bony bridge formation under different interventions. Results showed that the deformity angle and medial length of the tibia were significantly different between the grafted groups and nongrafted group at 4, 16, and 24 weeks postoperative (P<0.01). Results also showed no significant difference between fibrin-graft and fat-graft groups (P>0.05). Furthermore, the bone mineralization density of bony bridge induced by injury was significantly different between the grafted group and nongrafted group at 4, 16, and 24 weeks postoperative (P<0.01). Histological findings showed that bony repair after physeal injury was inhibited by both fibrin and fat interventions. We concluded that fibrin could be a substitute of adipose tissue in preventing the deformities induced by epiphyseal injury. Similar to autogenous fat, fibrin was found to alleviate limb shortness and prevent angular malformation by forming a scar instead of a bony bridge. The use of fibrin can help us to develop effective and compound intervention grafts to prevent skeletal deformity and regenerate normal cartilage tissue in the future.

  16. Fibrin glue inhibits migration of ocular surface epithelial cells.

    PubMed

    Yeung, A M; Faraj, L A; McIntosh, O D; Dhillon, V K; Dua, H S

    2016-10-01

    PurposeFibrin glue has been used successfully in numerous ophthalmic surgical procedures. Recently, fibrin glue has been used in limbal stem cell transplantation to reduce both operative time and to negate the need for sutures. The aim of this study was to determine the effects of fibrin glue on epithelial cell migration in vitro.MethodsCorneoscleral rims were split to retain the epithelial layer, Bowman's layer, and anterior stroma. Rims were cut into eight equal-sized pieces and were placed directly on culture plates or affixed with fibrin glue. Rims were maintained in culture for 25 days and epithelial cell growth was monitored. Cells were photographed to measure area or growth and immunofluorescence staining of explants for fibrin was performed.ResultsExplants that were glued demonstrated significantly delayed epithelial cell growth and migration as compared with explants without glue. By day 16, all fibrin glue had dissolved and coincided with onset of cell growth from glued explants. Cell growth commenced between days 3 and 4 for control explants without glue and around days 14-16 for explants with fibrin glue.ConclusionsFibrin glue delays epithelial cell migration by acting as a physical barrier and can potentially interfere with explant-derived limbal epithelial cell migration on to the corneal surface. We propose that glue should be used to attach the conjunctival frill of the limbal explant but care should be taken to ensure that the glue does not wrap around the explant if used to secure the explant as well. Strategic use of glue, to attach the recessed conjunctiva, can be advantageous in delaying conjunctival cell migration and reducing the need for sequential sector conjunctival epitheliectomy.

  17. Multivalent viral capsids with internal cargo for fibrin imaging.

    PubMed

    Obermeyer, Allie C; Capehart, Stacy L; Jarman, John B; Francis, Matthew B

    2014-01-01

    Thrombosis is the cause of many cardiovascular syndromes and is a significant contributor to life-threatening diseases, such as myocardial infarction and stroke. Thrombus targeted imaging agents have the capability to provide molecular information about pathological clots, potentially improving detection, risk stratification, and therapy of thrombosis-related diseases. Nanocarriers are a promising platform for the development of molecular imaging agents as they can be modified to have external targeting ligands and internal functional cargo. In this work, we report the synthesis and use of chemically functionalized bacteriophage MS2 capsids as biomolecule-based nanoparticles for fibrin imaging. The capsids were modified using an oxidative coupling reaction, conjugating ∼90 copies of a fibrin targeting peptide to the exterior of each protein shell. The ability of the multivalent, targeted capsids to bind fibrin was first demonstrated by determining the impact on thrombin-mediated clot formation. The modified capsids out-performed the free peptides and were shown to inhibit clot formation at effective concentrations over ten-fold lower than the monomeric peptide alone. The installation of near-infrared fluorophores on the interior surface of the capsids enabled optical detection of binding to fibrin clots. The targeted capsids bound to fibrin, exhibiting higher signal-to-background than control, non-targeted MS2-based nanoagents. The in vitro assessment of the capsids suggests that fibrin-targeted MS2 capsids could be used as delivery agents to thrombi for diagnostic or therapeutic applications.

  18. Microporous Nanofibrous Fibrin-based Scaffolds for Bone Tissue Engineering

    PubMed Central

    Osathanon, Thanaphum; Linnes, Michael L.; Rajachar, Rupak M.; Ratner, Buddy D.; Somerman, Martha J.; Giachelli, Cecilia M.

    2008-01-01

    The fibrotic response of the body to synthetic polymers limits their success in tissue engineering and other applications. Though porous polymers have demonstrated improved healing, difficulty in controlling their pore sizes and pore interconnections has clouded the understanding of this phenomenon. In this study, a novel method to fabricate natural polymer/calcium phosphate composite scaffolds with tightly controllable pore size, pore interconnection, and calcium phosphate deposition was developed. Microporous, nanofibrous fibrin scaffolds were fabricated using sphere-templating methods. Composite scaffolds were created by solution deposition of calcium phosphate on fibrin surfaces or by direct incorporation of nanocrystalline hydroxyapatite (nHA). The SEM results showed that fibrin scaffolds exhibited a highly porous and interconnected structure. Osteoblast-like cells, obtained from murine calvaria, attached, spread and showed a polygonal morphology on the surface of the biomaterial. Multiple cell layers and fibrillar matrix deposition were observed. Moreover, cells seeded on mineralized fibrin scaffolds exhibited significantly higher alkaline phosphatase activity as well as osteoblast marker gene expression compared to fibrin scaffolds and nHA incorporated fibrin scaffolds (0.25 g and 0.5 g). All types of scaffolds were degraded both in vitro and in vivo. Furthermore, these scaffolds promoted bone formation in a mouse calvarial defect model and the bone formation was enhanced by addition of rhBMP-2. PMID:18640716

  19. Shear dependence of the fibrin coagulation kinetics in vitro.

    PubMed

    Tippe, A; Müller-Mohnssen, H

    1993-12-01

    Fibrin thrombus formation, in vivo and in vitro, preferentially occurs in regions of retarded, recirculating flow which promote local variations of the distribution of blood components, e.g. thrombin, and shear rates. To better understand the effects of shear forces on the thrombin induced fibrin coagulation process the time course of fibrin formation in a fibrinogen/thrombin solution was studied for different shear rates gamma (0 s-1 < or = gamma < or = 500 s-1) and thrombin concentrations cthr (0.1 units/ml < or = cthr < or = 1.0 units/ml). The clotting curves at zero shear and the shear induced alterations of these curves could essentially be described in terms of a reaction kinetics defined by two rate coefficients k1, k2 which can be attributed to fibrinogen cleavage by thrombin and fibrin polymerisation, respectively. For cthr > approximately 0.5 units/ml and gamma > approximately 15 s-1 an additional mechanism, presumably fibrin breakage, had to be assumed. The rate coefficient k2 was markedly more affected by cthr and shear forces then was k1. The results fit well to the growth kinetics of fibrin thrombi formed in glass models of an arterial branching.

  20. The economics of pit and fissure sealants in preventive dentistry: a review.

    PubMed

    Kitchens, Dinah H

    2005-08-15

    Oral diseases are progressive, cumulative, and become more intricate to treat with advancement. While dental caries is an infectious transmissible disease with children being at the highest risk, primary prevention can reduce this risk. Primary prevention in dentistry is usually considered to be community fluoridated water supplies, professional fluoride treatments, and pit and fissure sealants. While community fluoridated water supplies have been proven to be cost-effective, the cost-effectiveness of pit and fissure sealants has primarily been studied in school-based programs of children from low socio-economic backgrounds. Dental sealant programs are just one way to help increase primary prevention in the oral health disparities of children. The purpose of this paper is to review the literature regarding the cost-effectiveness of pit and fissure sealants as a preventive strategy in preventive dentistry.

  1. Bond strength and microleakage of self-adhesive and conventional fissure sealants.

    PubMed

    Simsek Derelioglu, Sera; Yilmaz, Yucel; Celik, Pelin; Carikcioglu, Burak; Keles, Sultan

    2014-01-01

    The aim of this study was to compare the shear bond strengths (SBS), failure modes (adhesive, cohesive, or mixed), and marginal microleakage occurrence of conventional resin (CR)-based, glass ionomer (GI)-based, and self-adhesive resin (SAR)-based fissure sealants with or without prior phosphoric acid (PA) etching. Fifty extracted premolars were randomly and equally assigned into five groups -G1:PA+CR, G2:PA+GI, G3:GI, G4:PA+SAR, and G5:SAR. Prior PA etching significantly (p<0.05) increased the SBSs of sealants. Adhesive failure mainly occurred in teeth treated with SAR- or GI-based fissure sealants, and cohesive failure mainly occurred in PA-etched teeth. Microleakage occurrence differed significantly (p<0.05) among the five groups of treated teeth. We concluded that conditioning of a tooth's enamel surface is crucial to creating strong bonds and leak-free sealing between tooth and fissure sealant.

  2. Effect of sealants of the sound absorption coefficients of acoustical friable insulating materials

    NASA Astrophysics Data System (ADS)

    Wayman, J. L.; Lory, M. K.

    1984-10-01

    Acoustical friable insulating materials (AFIM), which often in the past contained asbestos, have been used for sound control since the mid 1930's. Because of their widespread use and the ease of fiber dissemination, friable asbestos materials are considered to be the major source of asbestos fiber contamination in the indoor environment. Encapsulation of asbestos materials with a commercial sealant product is one of several methods used to control potential asbestos exposure in rooms. A sealant product that preserves most of the acoustical properties of the material is preferred in this usage. AFIM sample materials were treated with 6 types of sealants and the effects on normally incident absorption coefficients from 100 to 2500 Hz were measured using a fixed, dual-microphone technique. Penetrating type sealants were found to have a less detrimental effect on sound absorption than those of a bridging type.

  3. Evidence-based Clinical Practice Guideline for the Use of Pit-and-Fissure Sealants.

    PubMed

    2016-10-15

    This article presents evidence-based clinical recommendations for the use of pit-and-fissure sealants on the occlusal surfaces of primary and permanent molars in children and adolescents. A guideline panel convened by the American Dental Association (ADA) Council on Scientific Affairs and the American Academy of Pediatric Dentistry conducted a systematic review and formulated recommendations to address clinical questions in relation to the efficacy, retention, and potential side effects of sealants to prevent dental caries; their efficacy compared with fluoride varnishes; and a head-to-head comparison of the different types of sealant material used to prevent caries on pits-and-fissures of occlusal surfaces. This is an update of the ADA 2008 recommendations on the use of pit-and-fissure sealants on the occlusal surfaces of primary and permanent molars. The authors conducted a systematic search in MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and other sources to identify randomized controlled trials reporting on the effect of sealants (available on the U.S. market) when applied to the occlusal surfaces of primary and permanent molars. The authors used the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the quality of the evidence and to move from the evidence to the decisions. The guideline panel formulated 3 main recommendations. They concluded that sealants are effective in preventing and arresting pit-and-fissure occlusal carious lesions of primary and permanent molars in children and adolescents compared with the nonuse of sealants or use of fluoride varnishes. They also concluded that sealants could minimize the progression of non-cavitated occlusal carious lesions (also referred to as initial lesions) that receive a sealant. Finally, based on the available limited evidence, the panel was unable to provide specific recommendations on the relative merits of 1 type of sealant material over the others

  4. Comparison of Microleakage and Penetration Depth between Hydrophilic and Hydrophobic Sealants in Primary Second Molar

    PubMed Central

    Chaugule, Vishwas B; Panse, Amey M

    2016-01-01

    Introduction Optimal pit and fissure sealing is determined by surface preparation techniques and choice of materials. The performance of pit and fissure sealant materials has been intensively investigated, yet no single product is reported as an ideal sealant. In children, moisture control during cavity preparation is always a big challenge, and hence, hydrophilic sealants have been developed. Aim To compare the microleakage and penetration depth of hydrophilic and hydrophobic sealants using acid-etching on dry and moist surfaces. Materials and methods Recently, extracted 28 2nd primary molars are assigned to two groups (hydrophobic group I; hydrophilic group II) depending on the surface condition (dry group: A1 and B1; moist group: A2 and B2) of 7 teeth in each group. Samples from group A1 and B1 are cleaned and dried with a 3-way syringe and etched with etching gel, and sealant is applied to the fissures and cured with visible light. Sample from A2 and B2 are immersed in 0.1 mL of fresh whole human saliva for 20 seconds and dried using a pellet cotton, and the same procedure is carried out. All samples are subjected to 1000 thermal cycles and sectioned to compare the depth of penetration and microleakage. Sections will be examined under light microscope and analyzed using an image analysis software (SigmaScan). Results The least microleakage was seen with hydrophilic sealant under moist surface condition, and the depth of penetration of hydrophobic sealant was found to be better than that of hydrophilic sealant in both dry and moist surface conditions. Conclusion Hydrophilic pit and fissure sealants showed higher tolerance to saliva contamination with less microleakage, but in terms of penetration ability hydrophobic sealants were found to be superior. How to cite this article Gawali PN, Chaugule VB, Panse AM. Comparison of Microleakage and Penetration Depth between Hydrophilic and Hydrophobic Sealants in Primary Second Molar. Int J Clin Pediatr Dent 2016

  5. Evidence-based Clinical Practice Guideline for the Use of Pit-and-Fissure Sealants.

    PubMed

    2016-10-01

    This article presents evidence-based clinical recommendations for the use of pit-and-fissure sealants on the occlusal surfaces of primary and permanent molars in children and adolescents. A guideline panel convened by the American Dental Association (ADA) Council on Scientific Affairs and the American Academy of Pediatric Dentistry conducted a systematic review and formulated recommendations to address clinical questions in relation to the efficacy, retention, and potential side effects of sealants to prevent dental caries; their efficacy compared with fluoride varnishes; and a head-to-head comparison of the different types of sealant material used to prevent caries on pits-and-fissures of occlusal surfaces. This is an update of the ADA 2008 recommendations on the use of pit-and-fissure sealants on the occlusal surfaces of primary and permanent molars. The authors conducted a systematic search in MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and other sources to identify randomized controlled trials reporting on the effect of sealants (available on the U.S. market) when applied to the occlusal surfaces of primary and permanent molars. The authors used the Grading of Recommendations Assessment, Development, and Evaluation approach to assess the quality of the evidence and to move from the evidence to the decisions. The guideline panel formulated 3 main recommendations. They concluded that sealants are effective in preventing and arresting pit-and-fissure occlusal carious lesions of primary and permanent molars in children and adolescents compared with the nonuse of sealants or use of fluoride varnishes. They also concluded that sealants could minimize the progression of non-cavitated occlusal carious lesions (also referred to as initial lesions) that receive a sealant. Finally, based on the available limited evidence, the panel was unable to provide specific recommendations on the relative merits of 1 type of sealant material over the others

  6. A One-Year Evaluation of a Free Fissure Sealant Program

    PubMed Central

    M, Bakhtiar; N, Azadi; A, Golkari

    2016-01-01

    Statement of Problem: Pit and fissure sealant therapy has been approved as an effective measure in the prevention of occlusal dental caries. Resin based materials are the most common materials used worldwide. A variety of resin based fissure sealants are produced and used. Most of them have been presented with ideal results in research environment. However, their effectiveness in the real life, especially in a mass application program such as Iran’s oral health reform plan is not clear. Objectives: To evaluate the longevity of different fissure sealant applied in Iran’s oral health reform plan in Fars Province (south of Iran) after one year. Materials and Methods: Seven counties were selected. One hundred 6- to 8-year-old school children who had undergone fissure sealant therapy in spring 2015 were randomly selected from each county. Their first molars were examined to evaluate the status of the fissure sealants which were applied one year ago. Data on the type/brand of fissure sealant materials, type and experience of clinicians who applied them, existence of a chair-side assistant, and whether the children were caries-free at the time of fissure sealant application were collected from the existing reports. Results: Data of 1974 teeth from 598 children were used for the final analysis. The effects of type/brand of the material was significant on the final results and remained significant (p < 0.001) after adjustments for the level of fluoride, urban/rural area, upper/lower jaw, type of clinician who applied the sealant, existence of a chair-side assistant, and child’s gender, age, and being caries-free. Conclusions: Many factors affect the success rate of a fissure sealant therapy program. The type/brand of the material remained significantly related to the success rate of the fissure sealant even after adjustments for other influencing factors. In this study, ClinproTM Sealant (3M/ESPE, USA) showed better longevity after one year of application. PMID

  7. Mapped Plot Patch Size Estimates

    Treesearch

    Paul C. Van Deusen

    2005-01-01

    This paper demonstrates that the mapped plot design is relatively easy to analyze and describes existing formulas for mean and variance estimators. New methods are developed for using mapped plots to estimate average patch size of condition classes. The patch size estimators require assumptions about the shape of the condition class, limiting their utility. They may...

  8. 3-year survival rates of retained composite resin and ART sealants using two assessment criteria.

    PubMed

    Hilgert, Leandro Augusto; Leal, Soraya Coelho; Freire, Gabriela Mesquita Lopes; Mulder, Jan; Frencken, Jo E

    2017-05-04

    The aim was to test the null-hypothesis that there is no difference in the cumulative survival rate of retained composite resin (CR) sealants and a high-viscosity glass-ionomer Atraumatic Restorative Treatment (ART) sealant in first permanent molars calculated according to the traditional and the modified retention assessment criteria over a period of 3 years. This cluster-randomized controlled clinical trial consisted of 123 schoolchildren, 6-7-years-old. At baseline, high-caries risk pits and fissures of fully erupted first permanent molars were treated with CR and ART sealants. Evaluations were performed after 0.5, 1, 2 and 3 years. Retention was scored for free-smooth surface and for each of three sections into which the occlusal surface had been divided. The modified criterion differed from the traditional in that it determined an occlusal sealant to be a failure when at least one section contained no visible sealant material. Data were analysed according to the PHREG model with frailty correction, Wald-test, ANOVA and t-test, using the Jackknife procedure. The cumulative survival rates for retained CR and ART sealants in free-smooth and occlusal surfaces for both criteria were not statistically significantly different over the 3 years. A higher percentage of retained CR sealants on occlusal surfaces was observed at longer evaluations. Cumulative survival rates were statistically significantly lower for the modified criterion in comparison to the traditional. The modified retention assessment criterion should be used in future sealant-retention studies.

  9. Comparison of various concentrations of tricalcium phosphate nanoparticles on mechanical properties and remineralization of fissure sealants.

    PubMed

    Tavassoli-Hojjati, Sara; Atai, Mohammad; Haghgoo, Roza; Rahimian-Imam, Sara; Kameli, Somayeh; Ahmaian-Babaki, Fatemeh; Hamzeh, Faezeh; Ahmadyar, Maryam

    2014-07-01

    The aim of this study was to investigate the mechanical properties (flexural strength, micro-shear bond strength) and remineralizing potential of fissure sealants by adding various concentrations of β-tricalcium phosphate nanoparticles. This in-vitro study consisted of five experimental groups containing prepared nano-fisssure sealants (1-5 wt.% β-TCP nanoparticles) and two control groups containing a prepared and a commercial fissure sealant. Flexural/micro-shear bond strength values were measured using Zwick test machine. Cavities on sixty healthy premolar teeth were filled with the fissure sealants containing 0-5 wt.% of nano β-TCP. The samples were assessed for remineralization under scanning electron microscopy (SEM) and EDAX. Kolmogorov-Smirnov test, One-way ANOVA and Tukey's Post Hoc analysis/HSD were used to analyze the data. There was no significant difference between the flexural strengths/elastic modulus of the 0-5 wt.% nano β-TCP groups (p>0.05). The average flexural strength/elastic modulus of the prepared fissure sealant group (0%) was significantly higher than the commercial fissure sealant group (Clinpro) (p<0.05). There was no significant difference between micro-shear bond strengths of the experimental groups (1-5 wt.%), and between the commercial and the prepared (0%) fissure sealant groups (p>0.05). Examining the samples under SEM showed a significant increase in thickness of the intermediate layer with increasing concentrations of β-TCP nanoparticles (p<0.05). Addition of 1-5 wt.% β-TCP nanoparticles to the fissure sealants significantly increased the remineralization potential without affecting the mechanical properties.

  10. Relation Between PAHs and Coal-Tar-Based Pavement Sealant in Urban Environments (Invited)

    NASA Astrophysics Data System (ADS)

    Mahler, B. J.; van Metre, P. C.

    2010-12-01

    Since 2003, coal-tar-based sealant products have come under increased scrutiny as a source of PAHs in urban environments. Sealant (or sealcoat) is the black, shiny substance often applied to asphalt pavement, in particular parking lots and driveways, for esthetic and maintenance purposes. Coal-tar-based sealant, one of the two primary pavement sealant types on the market, typically is 20-35 percent coal-tar pitch, a known carcinogen that is more than 50 percent polycyclic aromatic hydrocarbons (PAHs). The PAH content of the coal-tar-based sealant product is about 1,000 times that of a similar, asphalt-based product, on average. This difference is reflected in regional differences in sealant use and PAH concentrations in pavement dust. In the central and eastern U.S., where the coal-tar-based formulation is prevalent, ΣPAH in mobile particles from sealed pavement have been shown to be about 1,000 times higher than in the western U.S., where the asphalt-based formulation is prevalent (the median ΣPAH concentrations are 2,200 mg/kg in the central and eastern U.S. and 2.1 mg/kg in the western U.S.). Source apportionment modeling indicates that, in the central and eastern U.S., particles from sealed pavement are contributing the majority of the PAHs in recently deposited (post-1990) lake sediment, with implications for ecological health, and that coal-tar-based sealant is the primary cause of upward trends in PAHs in U.S. urban lakes. From the standpoint of human health, research indicates that mobile particles from parking lots with coal-tar-based sealant are tracked indoors, resulting in elevated PAH concentrations in house dust. Coal-tar-based sealcoat being applied to an asphalt parking lot at the University of Texas Pickle Research Center.

  11. Comparison of Various Concentrations of Tricalcium Phosphate Nanoparticles on Mechanical Properties and Remineralization of Fissure Sealants

    PubMed Central

    Tavassoli-Hojjati, Sara; Atai, Mohammad; Haghgoo, Roza; Rahimian-Imam, Sara; Kameli, Somayeh; Ahmaian-Babaki, Fatemeh; Hamzeh, Faezeh; Ahmadyar, Maryam

    2014-01-01

    Objective: The aim of this study was to investigate the mechanical properties (flexural strength, micro-shear bond strength) and remineralizing potential of fissure sealants by adding various concentrations of β-tricalcium phosphate nanoparticles. Materials and Methods: This in-vitro study consisted of five experimental groups containing prepared nano-fisssure sealants (1–5 wt.% β-TCP nanoparticles) and two control groups containing a prepared and a commercial fissure sealant. Flexural/micro-shear bond strength values were measured using Zwick test machine. Cavities on sixty healthy premolar teeth were filled with the fissure sealants containing 0–5 wt.% of nano β-TCP. The samples were assessed for remineralization under scanning electron microscopy (SEM) and EDAX. Kolmogorov-Smirnov test, One-way ANOVA and Tukey’s Post Hoc analysis/HSD were used to analyze the data. Results: There was no significant difference between the flexural strengths/elastic modulus of the 0–5 wt.% nano β-TCP groups (p>0.05). The average flexural strength/elastic modulus of the prepared fissure sealant group (0%) was significantly higher than the commercial fissure sealant group (Clinpro) (p<0.05). There was no significant difference between micro-shear bond strengths of the experimental groups (1–5 wt.%), and between the commercial and the prepared (0%) fissure sealant groups (p>0.05). Examining the samples under SEM showed a significant increase in thickness of the intermediate layer with increasing concentrations of β-TCP nanoparticles (p<0.05). Conclusion: Addition of 1–5 wt.% β-TCP nanoparticles to the fissure sealants significantly increased the remineralization potential without affecting the mechanical properties. PMID:25584048

  12. Surface roughness and maintenance of surface sealants for resin composites after toothbrushing.

    PubMed

    Bonato, Fernanda; Spohr, Ana Maria; Mota, Eduardo Gonçalves; Rodrigues-Junior, Sinval Adalberto; Burnett, Luiz Henrique

    2016-02-01

    (1) To evaluate in vitro the surface roughness of a resin composite covered with three surface sealants and submitted to simulated toothbrushing for different periods; (2) Verify, through scanning electron microscopy (SEM), the presence of surface sealants after simulated toothbrushing; and (3) To evaluate whether the type of dentifrice influences the maintenance of the surface sealant. The study hypothesis was that neither variable would influence the surface roughness of the composite and the maintenance of the surface sealant. 108 specimens were prepared with the resin Amelogen Plus, and divided into six groups (n = 18) according to the type of surface sealant [Fortify (F), BisCover LV (B) and Permaseal (P)] and toothpaste [Total 12 Clean Mint (CT) and Colgate Total 12 Professional Whitening (PW)]. The samples were subjected to brushing cycles, simulating periods of 6, 12, 18, and 24 months. After each period, the surface roughness of the samples was measured. An additional group of 48 samples was prepared for SEM analysis. The results were analyzed by ANOVA with three fixed variables (sealants, time and toothpaste) and by Tukey's test (α = 0.05). BisCover had the lowest mean surface roughness (0.06 µm) compared with the sealants Fortify (0.09 µm) and Permaseal (0.08 µm), which were not statistically different. Fortify, at 12 months of brushing, had the highest mean roughness (0.13 µm). The mean roughness for the dentifrice CT was lower (0.07 µm) when compared with PW (0.08 µm) and was statistically different. Roughness increased up to 12 months of simulated brushing (0.04 µm, 0.08 µm and 0.11 µm), decreasing from the 18th month (0.08 µm) to the 24th month of brushing (0.07 µm). None of the sealants was observed (with SEM) to be completely removed from the resin at 24 months of brushing.

  13. Conversion degree, microhardness, microleakage and fluoride release of different fissure sealants.

    PubMed

    Kuşgöz, Adem; Tüzüner, Tamer; Ulker, Mustafa; Kemer, Bariş; Saray, Onur

    2010-11-01

    The purpose of this study was to determine the degree of conversion (DC), microhardness, microleakage and fluoride release of a nano-filled resin based fissure sealant (Grandio Seal, GS) and compare it with an un-filled resin based fissure sealant (Clinpro, CL) and a glass-ionomer based fissure sealant (Fuji Triage, FT). Disk shaped specimens were prepared from tested fissure sealants to determine the DC, Vicker hardness (VHN) and fluoride release (FR). The DC and VHN of each material was evaluated after 24 h. The cumulative fluoride concentrations were evaluated at 1 h, 6 h, 12 h, 1, 7, 15 and 30 days. For microleakage evaluation, fissure sealants were applied to the etched and dried enamel surfaces of sound third molar teeth according to the manufacturer's instructions (n=10). After the thermocycling and mechanical loading procedures, microleakage assessments were carried out. Data were analyzed using one-way ANOVA followed by a post hoc Tukey test, the Kruskal Wallis and Mann-Whitney U test (p<0.05). Results revealed differences regarding DC between all groups: FT (89%) > GS (55.02%) > CL (%51.10) (p<0.05). The VHN values were significantly different among all groups in the following order: GS > FT > CL (p<0.05). FT exhibited significantly higher microleakage scores compared to the CL and GS sealants (p<0.05). The FR of FT was significantly greater than CL and GS (p<0.05). Nano-filled resin based sealant can be used as an alternative to other fissure sealant materials because of its superior hardness results and feasible sealing ability.

  14. Synthetic phenolic antioxidants, including butylated hydroxytoluene (BHT), in resin-based dental sealants.

    PubMed

    Wang, Wei; Kannan, Pranav; Xue, Jingchuan; Kannan, Kurunthachalam

    2016-11-01

    Resin-based dental sealants (also referred to as pit-and-fissure sealants) have been studied for their contribution to bisphenol A (BPA) exposure in children. Nevertheless, little attention has been paid to the occurrence of other potentially toxic chemicals in dental sealants. In this study, the occurrence of six synthetic phenolic antioxidants (SPAs), including 2,6-di-tert-butyl-4-hydroxytoluene (BHT), 2,6-di-tert-butyl-4-(hydroxyethyl)phenol (BHT-OH), 3,5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-CHO), 2,6-di-tert-butylcyclohexa-2,5-diene-1,4-dione (BHT-Q), 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-COOH) and 2-tert-butyl-4-methoxyphenol (BHA), was examined in 63 dental sealant products purchased from the U.S. market. BHT was found in all dental sealants at median and maximum concentrations of 56.8 and 1020µg/g, respectively. The metabolites of BHT and BHA were detected in 39-67% of samples, at concentration ranges of sealants to inhibit oxidative reactions, remove free radicals, and inhibit potential polymerization, which would eventually prolong the shelf-life of the products. The estimated daily intake (EDI) of BHT, following sealant placement, based on a worst-case scenario (application on eight teeth at 8mg each tooth), was 930 and 6510ng/kg bw/d for adults and children, respectively. The EDI of BHT from dental sealants was several orders of magnitude lower than the current acceptable daily intake (ADI) proposed by the European Food Safety Authority (EFSA). Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Development of High Temperature, Improved Performance Polythioether Sealants, Coatings and Adhesives

    DTIC Science & Technology

    1986-06-30

    REPORT NO. NADC-87071-6 -0= Ifl1C FILE COPY in DEVELOPMENT OF HIGH TEMPERATURE, IMPROVED PERFORMANCE POLYTHIOETHER SEALANTS, COATINGS AND ADHESIVES ...Polythioether Sealants, Coatings, and Adhesives (UNCLASSIFIED) 12. PERSONAL AUTHOR(S) Lester Morris, David A. Jordan, Melvin B. Young 13a. TYPE OF REPORT...those of polyether urethanes providing th catalyst used in the polymerization is removed. Polythioether urethanes have significantly improved water and

  16. OMNEX surgical sealant in the extracorporeal repair of renal artery aneurysms.

    PubMed

    Garcia-Roig, Michael; Gorin, Michael A; Castellan, Miguel; Ciancio, Gaetano

    2011-11-01

    OMNEX (Ethicon, Inc.; Somerville, NJ) is a cyanoacrylate-based synthetic surgical sealant. To date, the use of OMNEX has only been described in a limited number of vascular surgery procedures. We present the cases of two patients who underwent successful extracorporeal renal artery aneurysm repair with the aid of OMNEX sealant. This report is the first evidence to suggest the utility of OMNEX in renovascular surgery.

  17. Long-term Imaging of the Lungs After Sealant Bronchoscopic Lung Volume Reduction.

    PubMed

    Lieberman, Sivan; Shulimzon, Tiberiu R; Davidson, Tima; Marom, Edith M

    2016-11-01

    The aim of the study was to assess the pulmonary temporal changes after bronchoscopic lung volume reduction (BLVR) using sealants for treatment of emphysema. We retrospectively assessed all chest computerized tomography (CT) and F-18 fluorodeoxyglucose (FDG) positron emission tomography CT scans of patients treated at our institution with BLVR. Eleven patients were treated with sealants: 4 with biological sealants and 7 with synthetic sealants. The first CT scan after biological sealant treatment showed no abnormalities in 8 lobes and 5 nodules, and 3 consolidations in 7 lobes. All findings resolved within 3 months, except for a nodule that decreased after 2 months and remained stable for 9 years. The first CT scan after utilizing the synthetic sealant showed abnormalities in each treated lobe: 19 nodules/masses (16 cavitary, 3 solid) and 3 consolidations. Follow-up CT scans were available for 16 nodules/masses: 1 resolved, 12 slowly decreased in size, 1 remained unchanged, and 2 grew. Of 3 consolidations 1 resolved and 2 decreased in size. FDG positron emission tomography CT scans performed in 2 patients showed FDG uptake higher than mediastinal background activity in 2 nodules in the same patient. Pulmonary changes after BLVR are variable. After treatment with biological sealants, most findings resolve within 3 months. In contrast, after synthetic sealants, although the majority regress over time, some show waxing and waning in growth that can mimic malignancy. FDG uptake in some of these lesions is suggestive of chronic inflammation. Radiologists should be aware of the spectrum of these pulmonary changes to avoid misdiagnosis of lung cancer.

  18. Microstructural and mechanical differences between digested collagen-fibrin co-gels and pure collagen and fibrin gels.

    PubMed

    Lai, Victor K; Frey, Christina R; Kerandi, Allan M; Lake, Spencer P; Tranquillo, Robert T; Barocas, Victor H

    2012-11-01

    Collagen and fibrin are important extracellular matrix (ECM) components in the body, providing structural integrity to various tissues. These biopolymers are also common scaffolds used in tissue engineering. This study investigated how co-gelation of collagen and fibrin affected the properties of each individual protein network. Collagen-fibrin co-gels were cast and subsequently digested using either plasmin or collagenase; the microstructure and mechanical behavior of the resulting networks were then compared with the respective pure collagen or fibrin gels of the same protein concentration. The morphologies of the collagen networks were further analyzed via three-dimensional network reconstruction from confocal image z-stacks. Both collagen and fibrin exhibited a decrease in mean fiber diameter when formed in co-gels compared with the pure gels. This microstructural change was accompanied by an increased failure strain and decreased tangent modulus for both collagen and fibrin following selective digestion of the co-gels. In addition, analysis of the reconstructed collagen networks indicated the presence of very long fibers and the clustering of fibrils, resulting in very high connectivities for collagen networks formed in co-gels.

  19. Fibrin glue mixed with platelet-rich fibrin as a scaffold seeded with dental bud cells for tooth regeneration.

    PubMed

    Yang, Kai-Chiang; Wang, Chun-Hao; Chang, Hao-Hueng; Chan, Wing P; Chi, Chau-Hwa; Kuo, Tzong-Fu

    2012-11-01

    Odontogenesis is a complex process with a series of epithelial-mesenchymal interactions and odontogenic molecular cascades. In tissue engineering of teeth from stem cells, platelet-rich fibrin (PRF), which is rich in growth factors and cytokines, may improve regeneration. Accordingly, PRF was added into fibrin glue to enrich the microenvironment with growth factors. Unerupted second molar tooth buds were harvested from miniature swine and cultured in vitro for 3 weeks to obtain dental bud cells (DBCs). Whole blood was collected for the preparation of PRF and fibrin glue before surgery. DBCs were suspended in fibrin glue and then enclosed with PRF, and the DBC-fibrin glue-PRF composite was autografted back into the original alveolar sockets. Radiographic and histological examinations were used to identify the regenerated tooth structure 36 weeks after implantation. Immunohistochemical staining was used to detect proteins specific to tooth regeneration. One pig developed a complete tooth with crown, root, pulp, enamel, dentin, odontoblast, cementum, blood vessels, and periodontal ligaments in indiscriminate shape. Another animal had an unerupted tooth that expressed cytokeratin 14, dentin matrix protein-1, vascular endothelial growth factor, and osteopontin. This study demonstrated, using autogenic cell transplantation in a porcine model, that DBCs seeded into fibrin glue-PRF could regenerate a complete tooth. Copyright © 2011 John Wiley & Sons, Ltd.

  20. Microstructural and Mechanical Differences Between Digested Collagen-Fibrin Co-Gels and Pure Collagen and Fibrin Gels

    PubMed Central

    Lai, Victor K.; Frey, Christina R.; Kerandi, Allan M.; Lake, Spencer P.; Tranquillo, Robert T.; Barocas, Victor H.

    2012-01-01

    Collagen and fibrin are important extra-cellular matrix (ECM) components in the body, providing structural integrity to various tissues. These biopolymers are also common scaffolds used in tissue engineering. This study investigated how co-gelation of collagen and fibrin affected the properties of each individual protein network. Collagen-fibrin co-gels were cast and subsequently digested using either plasmin or collagenase; the microstructure and mechanical behavior of the resulting networks were then compared with respective pure collagen or fibrin gels of the same protein concentration. The morphologies of the collagen networks were further analyzed via 3-D network reconstruction from confocal image z-stacks. Both collagen and fibrin exhibited a decrease in mean fiber diameter when formed in the co-gels compared to the pure gels; this microstructural change was accompanied by increased failure strain and decreased tangent modulus for both collagen and fibrin following selected digestion of the co-gels. In addition, analysis of the reconstructed collagen networks indicated presence of very long fibers and clustering of fibrils, resulting in very high connectivities for collagen networks formed in co-gels. PMID:22828381

  1. Evidence not practised: the underutilisation of preventive fissure sealants.

    PubMed

    Bonetti, D L

    2014-04-01

    International and UK professional organisations, Cochrane systematic reviews, and international and UK guidance documents all support the application of preventive fissure sealants (PFSs) as an effective treatment for reducing caries. However, PFSs are well known to be underutilised in primary care. This paper collates data from PFS-relevant studies in Scotland, which has a large population of children at caries risk, to identify the beliefs and factors dentists perceive as influencing their decision not to provide this treatment. This information provides a platform to suggest how to increase the application of PFSs in this region (a standardised audit incorporating evidence-based behaviour change techniques, supplemental guidance on how to implement gold-standard recommendations in practice, training). This may also be relevant outside of Scotland, as well as to the implementation of other evidence-based behaviours in practice.

  2. Patient blood management: use of topical hemostatic and sealant agents.

    PubMed

    Ozawa, Sherri

    2013-11-01

    Patient blood management is the scientific use of safe, effective medical and surgical techniques designed to conserve blood, prevent anemia, decrease bleeding, and optimize coagulation in an effort to improve patient outcomes. Perioperative and primary care nurses play a vital role in promoting and making the best use of patient blood management and can play a key role in implementing effective strategies that decrease or eliminate patient exposure to allogeneic blood. The fast and effective minimization of intraoperative bleeding is integral in an effective blood management program. Topical hemostatic and sealant agents can be used to improve blood conservation, reduce overall procedure time, and contribute to faster patient recovery based on specific clinical situations. The proper selection of hemostatic agents can greatly influence the patient's clinical outcomes.

  3. Effect of different prophylaxis methods on sealant adhesion.

    PubMed

    Sol, E; Espasa, E; Boj, J R; Canalda, C

    2000-01-01

    The objective of this study was to evaluate the retention of a light-cured sealant using previously different prophylaxis methods and two different etching times, thirty and fifteen seconds. Eighty, third molars surgically extracted were sectioned into two halves (buccal and lingual). The teeth were divided into 8 groups of 20 samples each, according to prophylaxis type: pumice powder, fluoridated paste, sodium bicarbonate spray, and control (no prophylaxis); and etching time: 30 and 15 seconds. Tensile bond strengths were studied using a universal Instron testing machine. A statistical test ANOVA was used. No statistical differences were found when comparing both etching times, but when prophylaxis methods were compared a statistically significant higher retention was found in the sodium bicarbonate and fluoridated paste groups.

  4. A two-year clinical evaluation of glass ionomer and ormocer based fissure sealants.

    PubMed

    Guler, C; Yilmaz, Y

    2013-01-01

    The objective of the present study provides further data comparing retention, marginal integrity and caries preventive effects of two fissure sealants (glass ionomer based; GC Fuji VII Capsule [Fuji VII] and ormocer based; Admira Seal [AS]) in children. This study was designed as a randomized single-blind clinical trial. The permanent first molars (PFMs) of 50 children, 7-13 years of age (mean age: 8.9 +/- 1.3 years), were sealed with a split-mouth design. Fissure sealants applied to the PFMs according to the manufacturer's recommendations by one pediatric dentist. Clinical evaluation of the sealants was carried out to record retention, marginal integrity and presence of caries at 6, 12, 18 and 24 months after placement by the other pediatric dentist. Kaplan-Meier survival analysis and Cox's regression models were used to estimate the probability of two sealants success. Alpha and Bravo retention rates at the end of follow-up were 13% and 80% for Fuji VII and 3% and 83% for AS, respectively. For retention and marginal integrity between fissure sealants was found similar survival rates (p > 0.05). After 24 months, presence of caries was 16% for Fuji VII and 32% for AS (p < 0.05). Fuji VII and AS exhibited similar retention and marginal integrity during 24 months. However Fuji VII was showed better results than AS for caries preventive effect. Consequently, Fuji VII sealants may be a better choice for preventing occlusal caries.

  5. Retention Loss of Resin Based Fissure Sealants - a Valid Predictor for Clinical Outcome?

    PubMed Central

    Mickenautsch, Steffen; Yengopal, Veerasamy

    2013-01-01

    Purpose: The null-hypothesis that retention loss of resin fissure sealants predicts caries manifestation no more accurately than random values was tested. Methods: Systematic reviews were checked and electronic databases searched for clinical trials. Trials reporting on the retention of resin sealants and caries occurrence in permanent molar teeth, with minimum 24-month follow-up period, were included. Extracted data: number of sealed teeth, number of teeth without completely retained sealants, number of sealed teeth with caries. The number of teeth with complete sealant retention and absence of carious lesions/cavities was calculated; the predictive outcomes: true/false positive; false/true negative were established. Random values were generated as control-data. Diagnostic Odds ratios (DOR) were computed and tested for statistical difference. Summary Receiver Operating Characteristic curves were plotted. Results: 95 trials were found. Median DOR values were 1.21 and 0.28 for test- and control data, respectively. Wilcoxon test (z = 0.56; p = 0.58) and Sign test (z = 1.38; p = 0.17) results were statistically non-significant. The null-hypothesis was not rejected. Conclusions: Predictions based on the retention loss of resin sealants, regarding caries manifestation, was no more accurate than random guesses. Sealant retention loss appears not to be a valid predictor for clinical outcome. PMID:24078856

  6. Worker exposure to polychlorinated biphenyls in elastic polysulphide sealant renovation.

    PubMed

    Kontsas, Helena; Pekari, Kaija; Riala, Riitta; Bäck, Beatrice; Rantio, Tiina; Priha, Eero

    2004-01-01

    Worker exposure to polychlorinated biphenyls (PCBs) in renovation of prefabricated houses was assessed by biological monitoring of 24 PCB congeners including the 10 most abundant PCBs in elastic polysulphide sealants. Serum samples from 22 exposed and 21 non-exposed men were analysed using gas chromatography-mass spectrometry with negative chemical ionization. Total PCB concentration of 24 PCB congeners in workers' serum varied between 0.6 and 17.8 microg/l (mean 3.9 microg/l, median 1.9 microg/l). The Finnish upper reference limit for occupationally non-exposed persons (3 microg/l) was exceeded in the serum samples of 10 workers. Concentrations for non-exposed persons were 0.3-3.0 microg/l (mean 1.7 microg/l, median 1.5 microg/l). The concentration for the sum of the 10 most abundant PCB congeners in elastic polysulphide sealants in serum samples taken in autumn after the renovation season was 2-10 times higher than in samples from the same workers (n=5) taken in the previous spring. The concentrations of PCB congeners PCB 28, 52, 77, 101, 138, 153 and 180 in hygienic samples taken from the breathing zone of the workers were low, ranging from not detected to 3.1 microg/m3. The concentrations of PCB 28 and 52 in sera were positively correlated with the concentrations in air samples taken from the breathing zone of six workers (r=0.70 and 0.80).

  7. LIQUIDARMOR CM Flashing and Sealant, High Impact Technology Demonstration

    SciTech Connect

    Hun, Diana E.; Bhandari, Mahabir S.

    2016-12-01

    Air leakage is responsible for about 1.1 quads of energy or 6% of the total energy used by commercial buildings in the US. Consequently, infiltration and exfiltration are among the largest envelope-related contributors to the heating, ventilation, and air conditioning loads in commercial buildings. New air sealing technologies have recently emerged that aim to improve the performance of air barrier systems by simplifying their installation procedure. LIQUIDARMORTM CM Flashing and Sealant is an example of these new advanced material technologies. This technology is a spray-applied sealant and liquid flashing and can span gaps that are up to ¼ in. wide without a supporting material. ORNL verified the performance of LIQUIDARMORTM CM with field tests and energy simulations from a building in which LIQUIDARMORTM CM was one of components of the air barrier system. The Homeland Security Training Center (HTC) at the College of DuPage in Glen Ellyn, IL, served as the demonstration site. Blower door test results show the average air leakage rate in the demonstration site to be 0.15 cfm/ft2 at 1.57 psf, or 63% lower than the 0.4 cfm at 1.57 psf specified in the 2015 International Energy Conservation Code (IECC). According to simulation results, HTC lowered its annual heating and cooling cost by about $3,000 or 9% compared to a similar building that lacked an air barrier system. This demonstration project serves as an example of the level of building envelope airtightness that can be achieved by using air barrier materials that are properly installed, and illustrates the energy and financial savings that such an airtight envelope could attain.

  8. Does the amount of filler content in sealants used to prevent decalcification on smooth enamel surfaces really matter?

    PubMed

    Van Bebber, Lauren; Campbell, Phillip M; Honeyman, Allen L; Spears, Robert; Buschang, Peter H

    2011-01-01

    To determine how filler content and an acidic environment affect the retention of sealants placed on smooth enamel surfaces. A sample of 120 teeth was randomly divided into six subsamples. Three experimental sealants with identical formulas, with the exception of the amount of filler content (18%, 30%, 50%), were applied according to manufacturers' recommendations. Half of the subsamples were exposed to an acid environment (pH of 2.5) for 96 hours. With the use of a tooth-brushing simulator, each tooth was exposed to 15,000 brushing strokes, while a slurry of 1 : 3 toothpaste/neutral sodium bicarbonate cycled through the machine. Initial and final photographs were analyzed subjectively and objectively. Scanning electron microscope photomicrographs were used to evaluate the tooth surface. Subjective analyses showed significant (P < .05) filler effects, with the 18% filled sealant showing the least change, followed by the 30% sealant, then the 50% filled sealant, which showed the greatest loss. Objective analyses showed the same pattern of loss, but the differences between sealants were not statistically significant. Exposure to an acidic environment had no significant effect on sealant retention. SEMS showed a layer of sealant remaining on all of the sealed teeth evaluated. Filler content of resin sealant material affects the retention of sealants on smooth enamel surfaces; exposure to an acid environment has no effect on sealant retention. Within the limits of this study, highly filled resin sealants once saturated have the ability to endure the oral environment and remain on a smooth enamel surface, regardless of the amount of filler content.

  9. Influence of Shortened Light-curing Duration on the Potential of Resin-based Surface Sealants to Prevent Erosion.

    PubMed

    Wegehaupt, Florian; Jorge, Fabiana; Attin, Thomas; Tauböck, Tobias

    To determine whether reducing the light-curing time of resin-based surface sealants influences their potential to prevent erosion, as well as their mechanical stability and degree of conversion. 240 bovine dentin samples were randomly divided into 10 groups (1-10). The 24 samples of one group remained unsealed and served as control. Three groups were sealed with Seal&Protect, another three groups with K-0184 (experimental sealant), and the remaining three groups with Syntac Classic. One group of each sealant was light cured for 10 s, another group of that sealant for 5 s, and the last group of the respective sealant for 2 s at 1014 mW/cm2. After 7-day water storage, the first measurement of sealant permeability was performed. The samples were stored in hydrochloric acid (pH 2.3) for 24 h and the dentin calcium release was measured by atomic absorption spectroscopy. Following thermomechanical loading (5000 cycles, 5°/50°C, 12,000 brushing strokes), the second measurement of sealant permeability was performed. Additionally, the sealants' degrees of conversion (DC) were determined by FTIR spectroscopy. For the first and second measurements, no significant difference in the permeability of the sealants was observed when the light-curing duration was shortened. Additionally, no significant difference in the stability of the respective sealants was observed when light cured for different durations. Regarding DC, a significant influence of the light-curing duration was observed (p = 0.000). Shortening the light-curing time has no influence on permeability and stability of the investigated sealants. However, short light-curing times (2 s or 5 s) decrease the DC of the tested sealants.

  10. Clinical Evaluation of an Adhesive Sealant for Controlling Dental Caries in Naval Personnel: One-Year Results

    DTIC Science & Technology

    1974-08-20

    NUMBER 792 CLINICAL EVALUATION OF AN ADHESIVE SEALANT FOR CONTROLLING DENTAL CARIES IN NAVAL PERSONNEL: ONE-YEAR RESULTS by George T. Eden, CDR...s Approved for public release; distribution unlimited CLINICAL EVALUATION OF AN ADHESIVE SEALANT FOR CONTROLLING DENTAL CARIES IN NAVAL...SUMMARY PAGE THE PROBLEM To ascertain the effectiveness of an adhesive type sealant material in reducing the incidence of dental caries in Naval

  11. Expedition 11 patch

    NASA Image and Video Library

    2005-01-01

    ISS011-S-001 (January 2005) --- The emblem of the eleventh expedition to the International Space Station (ISS) emphasizes the roles of the United States and the Russian Federation in the multinational ISS partnership. The two rocket plumes, in the style of the flags of these two nations, represent the Russian Soyuz vehicles and the American space shuttles. The ISS image shows the configuration of the orbiting station at the start of the expedition, with docked Soyuz and Progress vehicles and the huge American solar panels. The names of the two crew members are shown on the margin of the patch. ISS Commander Sergei Krikalev and John Phillips, NASA ISS science officer and flight engineer, are expected to launch on a Soyuz vehicle and to be in orbit during the return to flight of the space shuttle. The crew explains, “The beauty of our home planet and the vivid contrasts of the space environment are shown by the blue and green Earth with the space station orbiting overhead, and by the bright stars, dark sky, and dazzling sun.” The NASA insignia design for shuttle flights and station increments is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced.

  12. Exp 45 Patch - FINALai

    NASA Image and Video Library

    2014-02-05

    ISS045-S-001 (July 2014) --- The Expedition 45 crew will conduct its journey of exploration and discovery from a summit whose foundation was built by past generations of pioneers, scientists, engineers and explorers. This foundation is represented by the book of knowledge at the bottom of the patch. Curves radiate from the book representing the flow of knowledge - and the hard work, sacrifice and innovation that makes human spaceflight possible. The pages written during Expedition 45 will serve to benefit humanity on Earth and in space. The International Space Station is represented by a single bright star soaring over the Earth, illuminating a path to future, more distant destinations. Note: The NASA insignia design for shuttle and space station flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, it will be publicly announced.

  13. STS-121 Mission Patch

    NASA Image and Video Library

    2005-06-01

    STS121-S-001 (June 2005) --- The STS-121 patch depicts the space shuttle docked with the International Space Station (ISS) in the foreground, overlaying the astronaut symbol with three gold columns and a gold star. The ISS is shown in the configuration that it will be in during the STS-121 mission. The background shows the nighttime Earth with a dawn breaking over the horizon. STS-121, ISS mission ULF1.1, is the final Shuttle Return to Flight test mission. This utilization and logistics flight will bring a multipurpose logistics module (MPLM) to the ISS with several thousand pounds of new supplies and experiments. In addition, some new orbital replacement units (ORUs) will be delivered and stowed externally on ISS on a special pallet. These ORUs are spares for critical machinery located on the outside of the ISS. During this mission the crew will also carry out testing of shuttle inspection and repair hardware, as well as evaluate operational techniques and concepts for conducting on-orbit inspection and repair. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

  14. Expedition 12 patch

    NASA Image and Video Library

    2005-09-01

    ISS012-S-001 (September 2005) --- The Expedition 12 patch represents both mankind’s permanent presence in space and future dreams of exploration. The International Space Station (ISS), featured prominently in the center, will continue to grow in its capability as a world-class laboratory and test bed for exploration. The vision of exploration is depicted by the moon and Mars. The star symbolizes mankind's destiny in space and is a tribute to the space explorers who have been lost in its pursuit. The Roman numeral XII in the background signifies the 12th expeditionary mission to the ISS. The NASA insignia design for Shuttle flights and Space Station increments is reserved for use by the astronauts and cosmonauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, it will be publicly announced.

  15. Retention of dental sealants placed on sound teeth and incipient caries lesions as part of a service-learning programme in rural areas in Mexico.

    PubMed

    Soto-Rojas, Armando E; Escoffié-Ramírez, Mauricio; Pérez-Ferrera, Gloriana; Guido, Joseph A; Mantilla-Rodriguez, Andres A; Martinez-Mier, Esperanza A

    2012-11-01

    Dental sealants are an effective treatment for the prevention and management of caries. To determine the retention of sealants placed in a rural setting in Mexico as part of an international service-learning (ISL) programme and to determine associations between dental sealant's retention and caries diagnosis at the time of sealant placement. Children aged 6-15 were examined for dental caries, received sealants by dental students as part of an ISL programme, and were re-examined 4, 2, or 1 years after placement to assess sealant survival. Sealants were placed on permanent sound surfaces and enamel caries lesions [International Caries Assessment and Detection System (ICDAS) criteria]. Sealant survival was explored using Cochran-Mantel-Haenszel tests and multivariate prediction models. 219 (46%) of 478 (mean age = 10.53 SD = 5.11) children who had received sealants returned for a recall examination (mean age = 10.89 SD = 3.11). After 1-4 years, 96.4% to 60.6% of the sealants placed on sound teeth had survived, and for sealants placed on surfaces with enamel caries lesions (ICDAS 1-3), 94.2% to 55.6% had survived. Differences were not statistically significant. Sealants had survival rates comparable to those previously reported in the literature. Sealants placed on sound and enamel caries lesions had similar survival rates. © 2012 The Authors. International Journal of Paediatric Dentistry © 2012 BSPD, IAPD and Blackwell Publishing Ltd.

  16. Effect of Silver Nanoparticle-Added Pit and Fissure Sealant in the Prevention of Dental Caries in Children.

    PubMed

    Salas-López, Enid Karina; Pierdant-Pérez, Mauricio; Hernández-Sierra, Juan Francisco; Ruíz, Facundo; Mandeville, Peter; Pozos-Guillén, Amaury J

    The objective of this study was to evaluate the effects of pit and fissure sealant mixed with silver nanoparticles on dental caries, by means of monthly measurement of fluorescence with DIAGNOdent over six months. This study was divided in two phases: experimental and clinical. In the experimental phase, the adhesion and microleakage of the pit and fissure sealant experiment were evaluated. Two groups of 10 teeth, without serious carious lesions, were included. Conventional (group A) and silver nanoparticles (group B) were added to the pit and fissure sealant. For the clinical phase, a split-mouth study was performed on 40 children aged 6-10 years old with healthy, erupted permanent first molars. A conventional pit and fissure sealant or a silver nanoparticle-mixed sealant was randomly placed. Repeated measures analysis was performed. Conventional sealant presented an average microleakage of 30.6%, and the silver nanoparticle-mixed sealant showed 33.6% (P=NS). A three times greater reduction in fluorescence was found in the silver nanoparticles group compared to the conventional group (P<0.05). No sex- or age-based associations were found. The silver nanoparticle-mixed sealant reduced tooth demineralization significantly and likely increased remineralization, compared to the conventional sealant.

  17. Fibronectin alters the rate of formation and structure of the fibrin matrix.

    PubMed

    Ramanathan, Anand; Karuri, Nancy

    2014-01-10

    Plasma fibronectin is a vital component of the fibrin clot; however its role on clot structure is not clearly understood. The goal of this study was to examine the influence of fibronectin on the kinetics of formation, structural characteristics and composition of reconstituted fibrin clots or fibrin matrices. Fibrin matrices were formed by adding thrombin to 1, 2 or 4 mg/ml fibrinogen supplemented with 0-0.4 mg/ml fibronectin. The rate of fibrin matrix formation was then monitored by measuring light absorbance properties at different time points. Confocal microscopy of fluorescein conjugated fibrinogen was used to visualize the structural characteristics of fibrin matrices. The amount of fibronectin in fibrin matrices was determined through electrophoresis and immunoblotting of solubilized matrices. Fibronectin concentration positively correlated with the initial rate of fibrin matrix formation and with steady state light absorbance values of fibrin matrices. An increase in fibronectin concentration resulted in thinner and denser fibers in the fibrin matrices. Electrophoresis and immunoblotting showed that fibronectin was covalently and non-covalently bound to fibrin matrices and in the form of high molecular weight multimers. The formation of fibronectin multimers was attributed to cross-linking of fibronectin by trace amounts Factor XIIIa. These findings are novel because they link results from light absorbance studies to microcopy analyses and demonstrate an influence of fibronectin on fibrin matrix structural characteristics. This data is important in developing therapies that destabilize fibrin clots.

  18. A CCR2 macrophage endocytic pathway mediates extravascular fibrin clearance in vivo.

    PubMed

    Motley, Michael P; Madsen, Daniel H; Jürgensen, Henrik J; Spencer, David E; Szabo, Roman; Holmbeck, Kenn; Flick, Matthew J; Lawrence, Daniel A; Castellino, Francis J; Weigert, Roberto; Bugge, Thomas H

    2016-03-03

    Extravascular fibrin deposition accompanies many human diseases and causes chronic inflammation and organ damage, unless removed in a timely manner. Here, we used intravital microscopy to investigate how fibrin is removed from extravascular space. Fibrin placed into the dermis of mice underwent cellular endocytosis and lysosomal targeting, revealing a novel intracellular pathway for extravascular fibrin degradation. A C-C chemokine receptor type 2 (CCR2)-positive macrophage subpopulation constituted the majority of fibrin-uptaking cells. Consequently, cellular fibrin uptake was diminished by elimination of CCR2-expressing cells. The CCR2-positive macrophage subtype was different from collagen-internalizing M2-like macrophages. Cellular fibrin uptake was strictly dependent on plasminogen and plasminogen activator. Surprisingly, however, fibrin endocytosis was unimpeded by the absence of the fibrin(ogen) receptors, αMβ2 and ICAM-1, the myeloid cell integrin-binding site on fibrin or the endocytic collagen receptor, the mannose receptor. The study identifies a novel fibrin endocytic pathway engaged in extravascular fibrin clearance and shows that interstitial fibrin and collagen are cleared by different subsets of macrophages employing distinct molecular pathways.

  19. A CCR2 macrophage endocytic pathway mediates extravascular fibrin clearance in vivo

    PubMed Central

    Motley, Michael P.; Madsen, Daniel H.; Jürgensen, Henrik J.; Spencer, David E.; Szabo, Roman; Holmbeck, Kenn; Flick, Matthew J.; Lawrence, Daniel A.; Castellino, Francis J.; Weigert, Roberto

    2016-01-01

    Extravascular fibrin deposition accompanies many human diseases and causes chronic inflammation and organ damage, unless removed in a timely manner. Here, we used intravital microscopy to investigate how fibrin is removed from extravascular space. Fibrin placed into the dermis of mice underwent cellular endocytosis and lysosomal targeting, revealing a novel intracellular pathway for extravascular fibrin degradation. A C-C chemokine receptor type 2 (CCR2)-positive macrophage subpopulation constituted the majority of fibrin-uptaking cells. Consequently, cellular fibrin uptake was diminished by elimination of CCR2-expressing cells. The CCR2-positive macrophage subtype was different from collagen-internalizing M2-like macrophages. Cellular fibrin uptake was strictly dependent on plasminogen and plasminogen activator. Surprisingly, however, fibrin endocytosis was unimpeded by the absence of the fibrin(ogen) receptors, αMβ2 and ICAM-1, the myeloid cell integrin-binding site on fibrin or the endocytic collagen receptor, the mannose receptor. The study identifies a novel fibrin endocytic pathway engaged in extravascular fibrin clearance and shows that interstitial fibrin and collagen are cleared by different subsets of macrophages employing distinct molecular pathways. PMID:26647393

  20. Foam-like compression behavior of fibrin networks

    PubMed Central

    Litvinov, Rustem I.; Weisel, John W.; Alber, Mark S.; Purohit, Prashant K.

    2016-01-01

    The rheological properties of fibrin networks have been of long-standing interest. As such there is a wealth of studies of their shear and tensile responses, but their compressive behavior remains unexplored. Here, by characterization of the network structure with synchronous measurement of the fibrin storage and loss moduli at increasing degrees of compression, we show that the compressive behavior of fibrin networks is similar to that of cellular solids. A non-linear stress-strain response of fibrin consists of three regimes: 1) an initial linear regime, in which most fibers are straight, 2) a plateau regime, in which more and more fibers buckle and collapse, and 3) a markedly non-linear regime, in which network densification occurs by bending of buck-led fibers and inter-fiber contacts. Importantly, the spatially non-uniform network deformation included formation of a moving “compression front” along the axis of strain, which segregated the fibrin network into compartments with different fiber densities and structure. The Young’s modulus of the linear phase depends quadratically on the fibrin volume fraction while that in the densified phase depends cubically on it. The viscoelastic plateau regime corresponds to a mixture of these two phases in which the fractions of the two phases change during compression. We model this regime using a continuum theory of phase transitions and analytically predict the storage and loss moduli which are in good agreement with the experimental data. Our work shows that fibrin networks are a member of a broad class of natural cellular materials which includes cancellous bone, wood and cork. PMID:25982442

  1. Ultrastructural changes to rabbit fibrin and platelets due to aspartame.

    PubMed

    Pretorius, E; Humphries, P

    2007-01-01

    The coagulation process, including thrombin, fibrin, as well as platelets, plays an important role in hemostasis, contributing to the general well-being of humans. Fibrin formation and platelet activation are delicate processes that are under the control of many small physiological events. Any one of these many processes may be influenced or changed by external factors, including pharmaceutical or nutritional products, e.g., the sweetener aspartame (L-aspartyl-L-phenylalanine methyl ester). It is known that phenylalanine is present at position P(9) and aspartate at position P(10) of the alpha-chain of human fibrinogen, and plays an important role in the conversion of fibrinogen to fibrin by the catalyst alpha-thrombin. The authors investigate the effect of aspartame on platelet and fibrin ultrastructure, by using the rabbit animal model and the scanning electron microscope. Animals were exposed to 34 mg/kg of aspartame 26x during a 2-month period. Aspartame-exposed fibrin networks appeared denser, with a thick matted fine fiber network covering thick major fibers. Also, the platelet aggregates appeared more granular than the globular control platelet aggregates. The authors conclude by suggesting that aspartame usage may interfere with the coagulation process and might cause delayed fibrin breakup after clot formation. They suggest this, as the fibrin networks from aspartame-exposed rabbits are more complex and dense, due to the netlike appearance of the minor, thin fibers. Aspartame usage should possibly be limited by people on anti-clotting medicine or those with prone to clot formation.

  2. Platelet rich fibrin in jaw defects

    NASA Astrophysics Data System (ADS)

    Nica, Diana; Ianes, Emilia; Pricop, Marius

    2016-03-01

    Platelet rich fibrin (PRF) is a tissue product of autologous origin abundant in growth factors, widely used in regenerative procedures. Aim of the study: Evaluation of the regenerative effect of PRF added in the bony defects (after tooth removal or after cystectomy) Material and methods: The comparative nonrandomized study included 22 patients divided into 2 groups. The first group (the test group) included 10 patients where the bony defects were treated without any harvesting material. The second group included 12 patients where the bony defects were filled with PRF. The bony defect design was not critical, with one to two walls missing. After the surgeries, a close clinically monitoring was carried out. The selected cases were investigated using both cone beam computer tomography (CBCT) and radiographic techniques after 10 weeks postoperatively. Results: Faster bone regeneration was observed in the bony defects filled with PRF comparing with the not grafted bony defects. Conclusions: PRF added in the bony defects accelerates the bone regeneration. This simplifies the surgical procedures and decreases the economic costs.

  3. Adhesion mechanisms of bituminous crack sealant to aggregate and laboratory test development

    NASA Astrophysics Data System (ADS)

    Hajialiakbari Fini, Elham

    Crack sealing is a common pavement maintenance treatment because it extends pavement service life. However, crack sealant often fails prematurely due to a loss of adhesion. Since current test methods are mostly empirical and only provide a qualitative measure of bond strength, they cannot predict sealant adhesive failure accurately. Hence, there is an urgent need for test methods based on bituminous sealant rheology that can better predict sealant field performance. This study introduces three laboratory tests aimed to assess the bond property of hot-poured crack sealant to pavement crack walls. The three tests are designed to serve the respective needs of producers, engineers, and researchers. The first test implements the principle of surface energy to measure the thermodynamic work of adhesion, which is the energy spent in separating the two materials at the interface. The work of adhesion is reported as a measure of material compatibility at an interface. The second test is a direct adhesion test, a mechanical test which is designed to closely resemble both the installation process and the crack expansion due to thermal loading. This test uses the Direct Tension Test (DTT) device. The principle of the test is to apply a tensile force to detach the sealant from its aggregate counterpart. The maximum load, Pmax, and the energy to separation, E, are calculated and reported to indicate interface bonding. The third test implements the principles of fracture mechanics in a pressurized circular blister test. The apparatus is specifically designed to conduct the test for bituminous crack sealant, asphalt binder, or other bitumen-based materials. In this test, a fluid is injected at a constant rate at the interface between the substrate (aggregate or a standard material) and the adhesive (crack sealant) to create a blister. The fluid pressure and blister height are measured as functions of time; the data is used to calculate Interfacial Fracture Energy (IFE), which is a

  4. Formulation study of oxybutynin patches.

    PubMed

    Minghetti, Paola; Cilurzo, Francesco; Pagani, Stefania; Casiraghi, Antonella; Assandri, Riccardo; Montanari, Luisa

    2007-01-01

    The present feasibility study was designed to obtain a monolayer patch containing oxybutynin (OXY) avoiding chemical permeation enhancers. The highest flux was obtained with a polydimethylsiloxane matrix patch. Because OXY crystals were detected in the matrix within a week, two amino methylmethacrylate copolymers (Eudragit E or Eudragit RS) were used as OXY crystallization inhibitors. A preliminary in vivo study indicated that flux from the stabilized patches had to be increased about 30-40%. This goal was reached by occlusion with a polyethylene layer.

  5. "Birdlime" technique using TachoSil tissue sealing sheet soaked with fibrin glue for sutureless vessel transposition in microvascular decompression: operative technique and nuances.

    PubMed

    Otani, Naoki; Toyooka, Terushige; Fujii, Kazuya; Kumagai, Kosuke; Takeuchi, Satoru; Tomiyama, Arata; Nakao, Yasuaki; Yamamoto, Takuji; Wada, Kojiro; Mori, Kentaro

    2017-08-11

    OBJECTIVE Microvascular decompression (MVD) is effective for the treatment of trigeminal neuralgia (TN), hemifacial spasm (HFS), and glossopharyngeal neuralgia. The transposition technique is the standard procedure to avoid adhesions and granuloma around the decompression site but is more complex and difficult to perform than the interposition technique. The authors describe a simple and safe MVD transposition procedure they call the "birdlime" technique, which uses a tissue glue-coated collagen sponge soaked with fibrin glue, and the results of this technique. METHODS The authors retrospectively reviewed the medical charts and radiographic findings of 27 consecutive patients with TN (8 patients) and HFS (19 patients) who, between January 2012 and December 2015, had undergone an MVD transposition procedure utilizing a tissue glue-coated collagen sponge (TachoSil tissue sealing sheet) soaked with fibrin glue (Tisseel 2-component fibrin sealant, vapor heated). Offending arteries among the patients with TN were the superior cerebellar artery (SCA) in 5 patients, the SCA and anterior inferior cerebellar artery (AICA) in 2, and the AICA in 1. Those among the patients with HFS were the vertebral artery (VA) in 3 patients, the VA and AICA in 4, the VA and posterior inferior cerebellar artery (PICA) in 3, the PICA in 4, the AICA in 1, the AICA-PICA in 3, and the PICA and AICA in 1. Operations were performed according to the Jannetta procedure. The offending artery was transposed and fixed to the dura mater of the petrous bone using TachoSil pieces soaked with fibrin glue. Postoperative constructive interference in steady-state MRI was performed to evaluate the change in the position of the offending artery. RESULTS Transposition of the offending artery was easily and safely performed in all patients. All patients had total remission of symptoms directly after the procedure. No severe complications occurred. The postoperative course was uneventful. No recurrences, adhesions

  6. Fibrin(ogen)olytic activity of bumblebee venom serine protease

    SciTech Connect

    Qiu Yuling; Choo, Young Moo; Yoon, Hyung Joo; Jia Jingming; Cui Zheng; Wang Dong; Kim, Doh Hoon; Sohn, Hung Dae; Jin, Byung Rae

    2011-09-01

    Bee venom is a rich source of pharmacologically active components; it has been used as an immunotherapy to treat bee venom hypersensitivity, and venom therapy has been applied as an alternative medicine. Here, we present evidence that the serine protease found in bumblebee venom exhibits fibrin(ogen)olytic activity. Compared to honeybee venom, bumblebee venom contains a higher content of serine protease, which is one of its major components. Venom serine proteases from bumblebees did not cross-react with antibodies against the honeybee venom serine protease. We provide functional evidence indicating that bumblebee (Bombus terrestris) venom serine protease (Bt-VSP) acts as a fibrin(ogen)olytic enzyme. Bt-VSP activates prothrombin and directly degrades fibrinogen into fibrin degradation products. However, Bt-VSP is not a plasminogen activator, and its fibrinolytic activity is less than that of plasmin. Taken together, our results define roles for Bt-VSP as a prothrombin activator, a thrombin-like protease, and a plasmin-like protease. These findings offer significant insight into the allergic reaction sequence that is initiated by bee venom serine protease and its potential usefulness as a clinical agent in the field of hemostasis and thrombosis. - Graphical abstract: Display Omitted Highlights: > Bumblebee venom serine protease (Bt-VSP) is a fibrin(ogen)olytic enzyme. > Bt-VSP activates prothrombin. > Bt-VSP directly degrades fibrinogen into fibrin degradation products. > Bt-VSP is a hemostatically active protein that is a potent clinical agent.

  7. Fibrin-fiber architecture influences cell spreading and differentiation

    PubMed Central

    Bruekers, Stéphanie M. C.; Jaspers, Maarten; Hendriks, José M. A.; Kurniawan, Nicholas A.; Koenderink, Gijsje H.; Kouwer, Paul H. J.; Rowan, Alan E.; T. S. Huck, Wilhelm

    2016-01-01

    ABSTRACT The mechanical and structural properties of the extracellular matrix (ECM) play an important role in regulating cell fate. The natural ECM has a complex fibrillar structure and shows nonlinear mechanical properties, which are both difficult to mimic synthetically. Therefore, systematically testing the influence of ECM properties on cellular behavior is very challenging. In this work we show two different approaches to tune the fibrillar structure and mechanical properties of fibrin hydrogels. Addition of extra thrombin before gelation increases the protein density within the fibrin fibers without significantly altering the mechanical properties of the resulting hydrogel. On the other hand, by forming a composite hydrogel with a synthetic biomimetic polyisocyanide network the protein density within the fibrin fibers decreases, and the mechanics of the composite material can be tuned by the PIC/fibrin mass ratio. The effect of the changes in gel structure and mechanics on cellular behavior are investigated, by studying human mesenchymal stem cell (hMSC) spreading and differentiation on these gels. We find that the trends observed in cell spreading and differentiation cannot be explained by the bulk mechanics of the gels, but correlate to the density of the fibrin fibers the gels are composed of. These findings strongly suggest that the microscopic properties of individual fibers in fibrous networks play an essential role in determining cell behavior. PMID:26910190

  8. Alignment of the Fibrin Network Within an Autologous Plasma Clot.

    PubMed

    Gessmann, Jan; Seybold, Dominik; Peter, Elvira; Schildhauer, Thomas Armin; Köller, Manfred

    2016-01-01

    Autologous plasma clots with longitudinally aligned fibrin fibers could serve as a scaffold for longitudinal axonal regrowth in cases of traumatic peripheral nerve injuries. Three different techniques for assembling longitudinally oriented fibrin fibers during the fibrin polymerization process were investigated as follows: fiber alignment was induced by the application of either a magnetic field or-as a novel approach-electric field or by the induction of orientated flow. Fiber alignment was characterized by scanning electron microscopy analysis followed by image processing using fast Fourier transformation (FFT). Besides FFT output images, area xmin to xmax, as well as full width at half maximum (FWHM) of the FFT graph plot peaks, was calculated to determine the relative degree of fiber alignment. In addition, fluorescently labeled human fibrinogen and mesenchymal stem cells (MSCs) were used to visualize fibrin and cell orientation in aligned and nonaligned plasma clots. Varying degrees of fiber alignment were achieved by the three different methods, with the electric field application producing the highest degree of fiber alignment. The embedded MSCs showed a longitudinal orientation in the electric field-aligned plasma clots. The key feature of this study is the ability to produce autologous plasma clots with aligned fibrin fibers using physical techniques. This orientated internal structure of an autologous biomaterial is promising for distinct therapeutic applications, such as a guiding structure for cell migration and growth dynamics.

  9. Fibrin-fiber architecture influences cell spreading and differentiation.

    PubMed

    Bruekers, Stéphanie M C; Jaspers, Maarten; Hendriks, José M A; Kurniawan, Nicholas A; Koenderink, Gijsje H; Kouwer, Paul H J; Rowan, Alan E; T S Huck, Wilhelm

    2016-09-02

    The mechanical and structural properties of the extracellular matrix (ECM) play an important role in regulating cell fate. The natural ECM has a complex fibrillar structure and shows nonlinear mechanical properties, which are both difficult to mimic synthetically. Therefore, systematically testing the influence of ECM properties on cellular behavior is very challenging. In this work we show two different approaches to tune the fibrillar structure and mechanical properties of fibrin hydrogels. Addition of extra thrombin before gelation increases the protein density within the fibrin fibers without significantly altering the mechanical properties of the resulting hydrogel. On the other hand, by forming a composite hydrogel with a synthetic biomimetic polyisocyanide network the protein density within the fibrin fibers decreases, and the mechanics of the composite material can be tuned by the PIC/fibrin mass ratio. The effect of the changes in gel structure and mechanics on cellular behavior are investigated, by studying human mesenchymal stem cell (hMSC) spreading and differentiation on these gels. We find that the trends observed in cell spreading and differentiation cannot be explained by the bulk mechanics of the gels, but correlate to the density of the fibrin fibers the gels are composed of. These findings strongly suggest that the microscopic properties of individual fibers in fibrous networks play an essential role in determining cell behavior.

  10. Phase-separated chitosan–fibrin microbeads for cell delivery

    PubMed Central

    Chen, Zhewei; Wang, Limin; Stegemann, Jan P.

    2011-01-01

    Matrix-enhanced delivery of cells is a promising approach to improving current cell therapies. Our objective was to create cell-laden composite microbeads that combine the attractive features of the natural polymers chitosan and fibrin. Liquid polydimethylsiloxane was used to emulsify a chitosan–fibrinogen solution containing suspended human fibroblast cells, followed by initiation of thrombin-mediated polymerization of fibrin and thermal/pH-mediated gelation of chitosan. Chitosan/fibrin weight percent (wt%) ratios of 100/0, 75/25, 50/50 and 25/75 were investigated. Microbead diameters ranged from 275 ± 99 μm to 38 ± 10 μm using impeller speeds from 600 to 1400 rpm. Fibroblasts remained viable on day 1 post-fabrication in all matrices, but cell viability was markedly higher in high-fibrin microbeads by day 8 post-fabrication. Cell spreading and interaction with the extracellular matrix was also markedly increased in high-fibrin matrices. Such composite microbeads containing viable entrapped cells have potential for minimally invasive delivery of cells for a variety of tissue repair applications. PMID:21736519

  11. Laminin-111 enriched fibrin hydrogels for skeletal muscle regeneration.

    PubMed

    Marcinczyk, Madison; Elmashhady, Hady; Talovic, Muhamed; Dunn, Andrew; Bugis, Faiz; Garg, Koyal

    2017-10-01

    Laminin (LM)-111 supplementation has improved muscle regeneration in several models of disease and injury. This study investigated a novel hydrogel composed of fibrinogen and LM-111. Increasing LM-111 concentration (50-450 μg/mL) in fibrin hydrogels resulted in highly fibrous scaffolds with progressively thinner interlaced fibers. Rheological testing showed that all hydrogels had viscoelastic behavior and the Young's modulus ranged from 2-6KPa. C2C12 myobalsts showed a significant increase in VEGF production and decrease in IL-6 production on LM-111 enriched fibrin hydrogels as compared to pure fibrin hydrogels on day 4. Western blotting results showed a significant increase in MyoD and desmin protein quantity but a significant decrease in myogenin protein quantity in myoblasts cultured on the LM-111 (450 μg/mL) enriched fibrin hydrogel. Combined application of electromechanical stimulation significantly enhanced the production of VEGF and IGF-1 from myoblast seeded fibrin-LM-111 hydrogels. Taken together, these observations offer an important first step toward optimizing a tissue engineered constructs for skeletal muscle regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Weight reduction is associated with increased plasma fibrin clot lysis.

    PubMed

    Brzezińska-Kolarz, Beata; Kolarz, Marek; Wałach, Angelika; Undas, Anetta

    2014-11-01

    Obesity is associated with an increased risk of vascular thrombotic events. We sought to investigate how obesity and weight loss affect plasma fibrin clot properties. A total of 29 obese patients were studied before and after 3-month low-fat diet. Plasma fibrin clot parameters, including fibrin clot permeation coefficient (Ks), the lag phase of the turbidity curve, clot lysis time (t 50%), maximum rate of increase in D-dimer levels, and maximum D-dimer concentrations, were determined. Low-fat diet resulted in the reduction of body weight (P < .0001), body mass index (P < .0001), fat mass (P < .0001), total cholesterol (P < .0001), low-density lipoprotein cholesterol (P = .0005), triglycerides (P = .008), and plasminogen activator inhibitor 1 (P = .02), but not in fibrinogen or C-reactive protein. The only change in fibrin clot variables was shorter t 50% (P = .02). Baseline t 50%, but not posttreatment, correlated with waist circumference (r = .44, p = .02). This study demonstrates that weight loss in obese people can increase the efficiency of fibrin clot lysis.

  13. Phase-separated chitosan-fibrin microbeads for cell delivery.

    PubMed

    Chen, Zhewei; Wang, Limin; Stegemann, Jan P

    2011-01-01

    Matrix-enhanced delivery of cells is a promising approach to improving current cell therapies. Our objective was to create cell-laden composite microbeads that combine the attractive features of the natural polymers chitosan and fibrin. Liquid polydimethylsiloxane was used to emulsify a chitosan-fibrinogen solution containing suspended human fibroblast cells, followed by initiation of thrombin-mediated polymerization of fibrin and thermal/pH-mediated gelation of chitosan. Chitosan/fibrin weight percent (wt%) ratios of 100/0, 75/25, 50/50 and 25/75 were investigated. Microbead diameters ranged from 275 ± 99 µm to 38 ± 10 µm using impeller speeds from 600 to 1400 rpm. Fibroblasts remained viable on day 1 post-fabrication in all matrices, but cell viability was markedly higher in high-fibrin microbeads by day 8 post-fabrication. Cell spreading and interaction with the extracellular matrix was also markedly increased in high-fibrin matrices. Such composite microbeads containing viable entrapped cells have potential for minimally invasive delivery of cells for a variety of tissue repair applications.

  14. Measurement of clottability of fibrin polymers using magnetic orientation

    NASA Astrophysics Data System (ADS)

    Iwasaka, M.; Ueno, S.; Tsuda, H.

    1996-04-01

    Fibrin polymers, as a kind of diamagnetic material, are oriented parallel to the direction of magnetic fields. We investigated the polymerization of partially digested fibrinogens in an 8 T magnetic field in order to observe the clotting ability of various sizes of fibrinogen fractions using a magnetic orientation technique. We purified high-molecular weight fraction (F1) and low-molecular weight fraction from human fibrinogen (F2). Fibrin gels were formed in an 8 T magnetic field for 9 h, and transmittancies were measured to evaluate the degree of magnetic orientation. The results show that a lack at the C-terminal half of one Aα chain did not affect the magnetic orientation of fibrin. We also investigated the effect of the digestion of fibrinogen by plasmin on the magnetic orientation of fibrin. The result shows that partially digested fibrin molecules also orient in an 8 T magnetic field. However, the degree of magnetic orientation significantly decreases when fragment X and fragment Y appear.

  15. Effect of collagen sponge and fibrin glue on bone repair

    PubMed Central

    SANTOS, Thiago de Santana; ABUNA, Rodrigo Paolo Flores; de ALMEIDA, Adriana Luisa Gonçalves; BELOTI, Marcio Mateus; ROSA, Adalberto Luiz

    2015-01-01

    ABSTRACT The ability of hemostatic agents to promote bone repair has been investigated using in vitro and in vivo models but, up to now, the results are inconclusive. Objective In this context, the aim of this study was to compare the potential of bone repair of collagen sponge with fibrin glue in a rat calvarial defect model. Material and Methods Defects of 5 mm in diameter were created in rat calvariae and treated with either collagen sponge or fibrin glue; untreated defects were used as control. At 4 and 8 weeks, histological analysis and micro-CT-based histomorphometry were carried out and data were compared by two-way ANOVA followed by Student-Newman-Keuls test when appropriated (p≤0.05). Results Three-dimensional reconstructions showed increased bone formation in defects treated with either collagen sponge or fibrin glue compared with untreated defects, which was confirmed by the histological analysis. Morphometric parameters indicated the progression of bone formation from 4 to 8 weeks. Additionally, fibrin glue displayed slightly higher bone formation rate when compared with collagen sponge. Conclusion Our results have shown the benefits of using collagen sponge and fibrin glue to promote new bone formation in rat calvarial bone defects, the latter being discreetly more advantageous. PMID:26814464

  16. Survival of sealants in molars affected by molar-incisor hypomineralization: 18-month follow-up.

    PubMed

    Fragelli, Camila Maria Bullio; Souza, Juliana Feltrin de; Bussaneli, Diego Girotto; Jeremias, Fabiano; Santos-Pinto, Lourdes Dos; Cordeiro, Rita de Cássia Loiola

    2017-04-27

    The objective of this study was to evaluate the clinical survival of sealants applied in first permanent molars (FPMs) affected by molar-incisor hypomineralization (MIH), at 18 months of follow-up. Forty-one first permanent molars were selected from 21 children, 6-8 years of age. MIH was classified by one calibrated examiner (kappa = 0.80) according to EAPD criteria. The inclusion criteria were fully erupted FPMs with MIH or sound FPMs (without MIH) for which sealant treatment was indicated. The FPMs were assigned to two groups: CG (control group) and HG (MIH group). Both groups were treated with sealant (FluroShield). Clinical follow-up was performed from baseline to 18 months to assess anatomical form, marginal adaptation, retention and presence of caries, according to criteria set by the United States Public Health Service-Modified, and was conducted by a blinded examiner (kappa = 0.80). The actuarial method was used to evaluate the survival of the sealants. The survival rates for the groups were compared using Fisher's exact test (α = 5%). The cumulative survival rates were 81% at 1 month, 68.8% at 6 months, 68.8% at 12 months, and 62.6% at 18 months for CG, and 88% at 1 month, 84% at 6 months, 76% at 12 months, and 72% at 18 months for HG. No significant difference was found between the groups. The sealants in molars affected by MIH presented a survival rate similar to the sealants in the control, suggesting that sealants may be an adequate approach for preventing carious lesions in MIH-affected molars.

  17. Depth of cure of sealants polymerized with high-power light emitting diode curing lights.

    PubMed

    Kitchens, Brandon; Wells, Martha; Tantbirojn, Daranee; Versluis, Antheunis

    2015-03-01

    To determine whether recommended short curing times of three high-power light emitting diode (LED) curing lights are sufficient to polymerize sealant materials. Opaque-unfilled sealant (Delton LC Opaque), opaque-filled sealant (UltraSeal XT plus), and clear-filled sealant (FluroShield) were light cured in a covered slot-mold using the manufacturers' shortest recommended curing times with three high-power LED lights (3-s VALO, 5-s Fusion, 10-s Smartlite). A 40-s cure with a quartz-tungsten halogen (QTH) light was used as control. Vickers hardness was measured 24 h after curing at the sealant surface and through the depth (0.5 mm increments) (N = 10). Results were analyzed with two-way anova (pair-wise multiple comparisons, significance level 0.05). The high-power LEDs did not cure the sealants as deep as the QTH. Delton LC Opaque showed the least depth of cure as hardness values beyond a depth of 0.5 mm were not measurable regardless of the curing light. Even for UltraSeal XT plus, when surface hardness was about the same with all lights, hardness decreased more rapidly with depth for the LEDs. FluroShield showed the slowest decline in hardness through the depth for all lights. Manufacturers' recommendations for shortest possible curing time with high-power LEDs were not sufficient for adequate polymerization of the tested sealants. © 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Adhesive systems under fissure sealants: yes or no?: A systematic review and meta-analysis.

    PubMed

    Bagherian, Ali; Sarraf Shirazi, Alireza; Sadeghi, Ramin

    2016-06-01

    The authors of this systematic review and meta-analysis had 2 aims: to evaluate fissure sealant retention with and without the use of an adhesive system and to compare fissure sealant retention using etch-and-rinse adhesive systems versus self-etching adhesive systems. The authors conducted a literature search (all articles published through November 1, 2015) to identify studies for inclusion in this systematic review. They assessed the quality of the evidence provided using the modified Jadad scale and performed meta-analyses using a random-effects model. The authors considered 12 studies that met the inclusion criteria for the systematic review. In addition, they used 5 of 9 studies related to the first part of the study and 3 of 4 studies related to the second part of the study that met the inclusion criteria for meta-analysis. In the analysis of the first part of the systematic review, the authors found that adhesive systems had a significant positive effect on fissure sealant (odds ratio, 3.294; 95% confidence interval, 1.292-8.401; P = .013). In the analysis of the second part of the systematic review, the authors found that etch-and-rinse adhesives were superior to self-etching adhesives in the fissure sealant procedure (odds ratio, 14.569; 95% confidence interval, 2.616-81.131; P = .002). The use of adhesive systems beneath fissure sealants can increase the retention of fissure sealants. Also, when adhesive systems are used with fissure sealants, etch-and-rinse systems are preferable. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

  19. Selective removal of composite sealants with near-UV laser pulses

    NASA Astrophysics Data System (ADS)

    Louie, Tiffany M.; Jones, Robert S.; Sarma, Anupama V.; Fried, Daniel

    2004-05-01

    It is often necessary to replace pit and fissure sealants and composite restorations. This task is complicated by the necessity for complete removal of the remaining composite to enable suitable adhesion of new composite. Previous studies have shown that lasers pulses from a frequency-tripled Nd:YAG laser (355-nm) can selectively remove residual composite after orthodontic bracket removal on enamel surfaces. UV laser light is preferentially absorbed by polymeric resins and the organic content of the tooth enamel. The objective of this study was to determine if such laser pulses are suitable for selective removal of the old composite from pit and fissure sealants and restorations without damaging surrounding sound tissues. Optical coherence tomography was used to acquire optical cross sections of the occlusal topography and peripheral tooth structure non-destructively before application of the sealants, after sealant application, and after sealant removal with 355-nm laser pulses with intensities ranging from 0-10 J/cm2. Thermocouples were used to monitor the temperature in the pulp chamber during composite removal under clinically relevant ablation rates, i.e., 30 Hz and 30 mJ per laser pulse. At an irradiation intensity of 1.3 J/cm2 pit and fissure sealants were completely removed without visible damage to the underlying enamel. At intensities above 1.5 J/cm2, the laser removes the resin layer while at the same time preferentially etching the surface of the enamel. Temperature excursions in the pulp chamber of extracted teeth was limited to less than 5°C if air-cooling was used during the rapid removal (1-2 min) of sealants, water-cooling was not needed. This is the first presentation of a method for the selective removal of composite restorative materials without damage to the underlying sound tooth structure.

  20. Fluoride release rate from an orthodontic sealant and its clinical implications.

    PubMed

    Soliman, Manal M; Bishara, Samir E; Wefel, James; Heilman, Judi; Warren, John J

    2006-03-01

    The objectives were to measure the rate and amount of fluoride ions released from the sealant over a period of 17 weeks and to determine whether the fluoride-releasing sealant has a recharging ability when fluoride ions are reintroduced into the environment. Disc-shaped specimens were prepared from two types of sealants: (1) 10 discs were made using a fluoride-releasing sealant and (2) 10 discs were made of a nonfluoride adhesive primer (control). An ion analyzer was used to measure the fluoride release using a fluoride ion-specific combination electrode. The results of the repeated measure analysis (F = 7.76) indicated that the fluoride-containing sealant released fluoride ions into the solution in sustained but significantly (P = .014) decreasing rates from a high of 0.074 +/- 0.04 ppm/week/mm2 in the first week to a low of 0.015 +/- 0.017 ppm/week/mm2 at the end of the 17th week. Furthermore, the Pro Seal discs had the ability to be recharged with fluoride ions introduced from a foaming solution of acidulated phosphate fluoride. The mean fluoride release rate one week after recharging was 0.354 +/- 0.095 ppm/week/mm2 and decreased to 0.014 +/- 0.009 ppm/week/mm2 after eight weeks. The control sealant showed no significant fluoride release and was unable to absorb the fluoride ions available in the solution. The fluoride-containing sealant Pro Seal released fluoride ions in sustained but significantly decreasing amounts. The Pro Seal discs had the ability to be recharged with fluoride ions.

  1. Microbial sealants do not decrease surgical site infection for clean-contaminated colorectal procedures.

    PubMed

    Doorly, M; Choi, J; Floyd, A; Senagore, A

    2015-05-01

    Surgical site infections (SSI) are costly complications that may cause significant morbidity and increase the cost of care, particularly in colorectal surgery. Microbial sealants (MS) are a new class of wound barriers aimed at decreasing SSI; however, there is only evidence of benefit in clean class 1 procedures. Based on its success in class 1 procedures, we hypothesized that a microbial sealant could reduce the rate of SSI by half for clean-contaminated colorectal procedures (class 2). This was a single institution, multihospital, prospective, randomized study approved by the institutional review board. The primary objective was to determine the rate of SSI when microbial sealant (InteguSeal© Kimberly-Clark) is used compared to control (no microbial sealant). Data collected included: open versus laparoscopy, age, body mass index (BMI), diabetes and morbidity [American Society of Anesthesiologists (ASA) class], hospital readmission, reoperation and wound dehiscence. Enrolled subjects received the same preoperative mechanical bowel preparation with oral antibiotics, operative skin preparation (Chloraprep), Surgical Care Improvement Project guidelines implementation), and postoperative care glycemic control for diabetics. A total of 100 subjects were recruited over 15 months (MS-50; no MS-50). The overall incidence of SSI was 12 %, 14 % (7/50) in the MS versus 10 % (5/50) in the no MS group (p = 0.545). SSI incidence with and without microbial sealant was not significantly different in either the open or the laparoscopic subgroup. Laparoscopy decreased absolute risk of SSI by 16 %. Secondary data (age, BMI, diabetes, ASA) and tertiary data (readmission, reoperation, wound dehiscence) were positively correlated with SSI. Microbial sealant as employed in this study did not appear to offer any benefit in a class 2 (clean contaminated) operative procedure when perioperative care is standardized. The relative benefit of laparoscopy was also confirmed but unaffected by

  2. Validity of Sealant Retention as Surrogate for Caries Prevention – A Systematic Review

    PubMed Central

    Mickenautsch, Steffen; Yengopal, Veerasamy

    2013-01-01

    Introduction/Aim To appraise the clinical literature in determining whether loss of complete sealant retention as surrogate endpoint is directly associated with caries occurrence on sealed teeth as its clinical endpoint and to apply the appraised evidence in testing the null-hypothesis that the retention/caries ratio between different types of sealant materials (resin and glass-ionomer cement) is not statistically significant ( = Prentice criterion for surrogate endpoint validity). Methods Databases searched PubMed/Medline, Directory of Open Access Journals; IndMed, Scielo. Systematic reviews were checked for suitable trials. The search terms: “fiss* AND seal*” and “fissure AND sealant” were used. Article selection criteria were: clinical trial reporting on the retention and caries occurrence of resin and/or glass-ionomer cement (GIC) fissure sealed permanent molar teeth; minimum 24-month follow-up period; systematic review or meta-analysis. Datasets and information were extracted from accepted trials. The principle outcome measure was the ratio of Risk of loss of complete retention to the Risk of caries occurrence per sealant type (RCR). Risk of bias was assessed in trials and sensitivity analysis with regard to potential confounding factors conducted. The null-hypothesis was tested by graphical and statistical methods. Results The risk of loss of complete retention of sealant materials was associated with the risk of caries occurrence for resin but not for GIC based sealants. The difference between RCR values of the two sealant types was statistically significant (p<0.05). The null-hypothesis was rejected. Conclusions The current clinical evidence suggests that complete retention of pit and fissure sealants may not be a valid surrogate endpoint for caries prevention as its clinical endpoint. Further research is required to corroborate the current results. PMID:24194861

  3. Creation of polar cap patches

    NASA Astrophysics Data System (ADS)

    Hosokawa, K.; Taguchi, S.; Ogawa, Y.

    2014-12-01

    Polar cap patches, which are islands of enhanced plasma density drifting anti-sunward, are one of the outstanding phenomena in the polar cap F region ionosphere. In the last decade, data from all-sky airglow imagers have been extensively used for better understanding the propagation of patches in the central polar cap region. But still, it has been rather difficult to capture the birth of patches in their generation region near the dayside cusp, because, in most places, the dayside part of the polar cap ionosphere is sunlit even in winter. In Longyearbyen (78.1N, 15.5E), Norway, however, optical observations are possible near the dayside cusp region in a limited period around the winter solstice. This enables us to directly image how polar cap patches are born in the cusp. In this paper, we present a few intervals of daytime optical observations, during which polar cap patches were generated within the field-of-view of an all-sky imager in Longyearbyen. During all the intervals studied here, we identified several signatures of poleward moving auroral forms (PMAF) in the equatorward half of the field-of-view, which are known as ionospheric manifestations of dayside reconnection. Interestingly, patches were directly produced from such poleward moving auroral signatures and propagated poleward along the anti-sunward convection near the cusp. In the literature, Lorentzen et al. (2012) first reported such a direct production of patches from PMAFs. During the current observations, however, we succeeded in tracking the propagation of patches until they reached the poleward edge of the field-of-view of the imager. This confirms that the faint airglow structures produced from PMAFs were actually transported for a long distance towards the central polar cap area; thus, polar cap patches were produced. From this set of observations, we suggest that polar cap patches during moderately disturbed conditions (i.e, non-storm time conditions) can be directly produced by the

  4. Formulation Optimization of Arecoline Patches

    PubMed Central

    Wu, Pao-Chu; Tsai, Pi-Ju; Lin, Shin-Chen; Huang, Yaw-Bin

    2014-01-01

    The response surface methodology (RSM) including polynomial equations has been used to design an optimal patch formulation with appropriate adhesion and flux. The patch formulations were composed of different polymers, including Eudragit RS 100 (ERS), Eudragit RL 100 (ERL) and polyvinylpyrrolidone K30 (PVP), plasticizers (PEG 400), and drug. In addition, using terpenes as enhancers could increase the flux of the drug. Menthol showed the highest enhancement effect on the flux of arecoline. PMID:24707220

  5. Formulation optimization of arecoline patches.

    PubMed

    Wu, Pao-Chu; Tsai, Pi-Ju; Lin, Shin-Chen; Huang, Yaw-Bin

    2014-01-01

    The response surface methodology (RSM) including polynomial equations has been used to design an optimal patch formulation with appropriate adhesion and flux. The patch formulations were composed of different polymers, including Eudragit RS 100 (ERS), Eudragit RL 100 (ERL) and polyvinylpyrrolidone K30 (PVP), plasticizers (PEG 400), and drug. In addition, using terpenes as enhancers could increase the flux of the drug. Menthol showed the highest enhancement effect on the flux of arecoline.

  6. Vital Signs: Dental Sealant Use and Untreated Tooth Decay Among U.S. School-Aged Children.

    PubMed

    Griffin, Susan O; Wei, Liang; Gooch, Barbara F; Weno, Katherine; Espinoza, Lorena

    2016-10-21

    Tooth decay is one of the greatest unmet treatment needs among children. Pain and suffering associated with untreated dental disease can lead to problems with eating, speaking, and learning. School-based dental sealant programs (SBSP) deliver a highly effective intervention to prevent tooth decay in children who might not receive regular dental care. SBSPs benefits exceed their costs when they target children at high risk for tooth decay. CDC used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014 to estimate current prevalences of sealant use and untreated tooth decay among low-income (≤185% of federal poverty level) and higher-income children aged 6-11 years and compared these estimates with 1999-2004 NHANES data. The mean number of decayed and filled first molars (DFFM) was estimated for children with and without sealants. Averted tooth decay resulting from increasing sealant use prevalence was also estimated. All reported differences are significant at p<0.05. From 1999-2004 to 2011-2014, among low- and higher-income children, sealant use prevalence increased by 16.2 and 8.8 percentage points to 38.7% and 47.8%, respectively. Among low-income children aged 7-11 years, the mean DFFM was almost three times higher among children without sealants (0.82) than among children with sealants. Approximately 6.5 million low-income children could potentially benefit from the delivery of sealants through SBSP. The prevalence of dental sealant use has increased; however, most children have not received sealants. Increasing sealant use prevalence could substantially reduce untreated decay, associated problems, and dental treatment costs.

  7. Characterization of Leukocyte-platelet Rich Fibrin, A Novel Biomaterial.

    PubMed

    Madurantakam, Parthasarathy; Yoganarasimha, Suyog; Hasan, Fadi K

    2015-09-29

    Autologous platelet concentrates represent promising innovative tools in the field of regenerative medicine and have been extensively used in oral surgery. Unlike platelet rich plasma (PRP) that is a gel or a suspension, Leukocyte-Platelet Rich Fibrin (L-PRF) is a solid 3D fibrin membrane generated chair-side from whole blood containing no anti-coagulant. The membrane has a dense three dimensional fibrin matrix with enriched platelets and abundant growth factors. L-PRF is a popular adjunct in surgeries because of its superior handling characteristics as well as its suturability to the wound bed. The goal of the study is to demonstrate generation as well as provide detailed characterization of relevant properties of L-PRF that underlie its clinical success.

  8. Fibrin breakdown products and fibrinolysis in renal disease

    PubMed Central

    Wardle, E. N.; Taylor, G.

    1968-01-01

    In chronic renal failure and after acute renal failure, fibrinogen levels are raised and there is diminished fibrinolysis as the result of renal damage. A similar situation is found in nephrosis, possibly due to fibrinolytic inhibitors. Increased levels of cryofibrinogen were found in one quarter of cases of acute nephritis, nephrosis, and acute and chronic renal failure. In addition, after acute renal failure low platelet counts, prolonged thrombin times, and high levels of fibrin degradation products, yet with diminished fibrinolysis, indicate that intravascular coagulation has occurred. A positive result for fibrin degradation products was found in 17 of 20 cases of acute renal failure but in none of 10 cases of chronic uraemia. Intravascular coagulation is a process in which fibrin is deposited in the glomerular filters and may account for anuria, and, in the renal vasculature, where it may cause ischaemic tubular necrosis. Images PMID:5697045

  9. Vasculogenesis and Angiogenesis in Modular Collagen-Fibrin Microtissues.

    PubMed

    Peterson, A W; Caldwell, D J; Rioja, A Y; Rao, R R; Putnam, A J; Stegemann, J P

    2014-10-01

    The process of new blood vessel formation is critical in tissue development, remodeling and regeneration. Modular tissue engineering approaches have been developed to enable the bottom-up assembly of more complex tissues, including vascular networks. In this study, collagen-fibrin composite microbeads (100-300 μm in diameter) were fabricated using a water-in-oil emulsion technique. Human endothelial cells and human fibroblasts were embedded directly in the microbead matrix at the time of fabrication. Microbead populations were characterized and cultured for 14 days either as free-floating populations or embedded in a surrounding fibrin gel. The collagen-fibrin matrix efficiently entrapped cells and supported their viability and spreading. By 7 days in culture, endothelial cell networks were evident within microbeads, and these structures became more prominent by day 14. Fibroblasts co-localized with endothelial cells, suggesting a pericyte-like function, and laminin deposition indicated maturation of the vessel networks over time. Microbeads embedded in a fibrin gel immediately after fabrication showed the emergence of cells and the coalescence of vessel structures in the surrounding matrix by day 7. By day 14, inosculation of neighboring cords and prominent vessel structures were observed. Microbeads pre-cultured for 7 days prior to embedding in fibrin gave rise to vessel networks that emanated radially from the microbead by day 7, and developed into connected networks by day 14. Lumen formation in endothelial cell networks was confirmed using confocal sectioning. These data show that collagen-fibrin composite microbeads support vascular network formation. Microbeads embedded directly after fabrication emulated the process of vasculogenesis, while the branching and joining of vessels from pre-cultured microbeads resembled angiogenesis. This modular microtissue system has utility in studying the processes involved in new vessel formation, and may be developed into

  10. Fibrin activates GPVI in human and mouse platelets.

    PubMed

    Alshehri, Osama M; Hughes, Craig E; Montague, Samantha; Watson, Stephanie K; Frampton, Jon; Bender, Markus; Watson, Steve P

    2015-09-24

    The glycoprotein VI (GPVI)-Fc receptor γ (FcRγ) chain is the major platelet signaling receptor for collagen. Paradoxically, in a FeCl3 injury model, occlusion, but not initiation of thrombus formation, is delayed in GPVI-deficient and GPVI-depleted mice. In this study, we demonstrate that GPVI is a receptor for fibrin and speculate that this contributes to development of an occlusive thrombus. We observed a marked increase in tyrosine phosphorylation, including the FcRγ chain and Syk, in human and mouse platelets induced by thrombin in the presence of fibrinogen and the αIIbβ3 blocker eptifibatide. This was not seen in platelets stimulated by a protease activated receptor (PAR)-4 peptide, which is unable to generate fibrin from fibrinogen. The pattern of tyrosine phosphorylation was similar to that induced by activation of GPVI. Consistent with this, thrombin did not induce tyrosine phosphorylation of Syk and the FcRγ chain in GPVI-deficient mouse platelets. Mouse platelets underwent full spreading on fibrin but not fibrinogen, which was blocked in the presence of a Src kinase inhibitor or in the absence of GPVI. Spreading on fibrin was associated with phosphatidylserine exposure (procoagulant activity), and this too was blocked in GPVI-deficient platelets. The ectodomain of GPVI was shown to bind to immobilized monomeric and polymerized fibrin. A marked increase in embolization was seen following FeCl3 injury in GPVI-deficient mice, likely contributing to the delay in occlusion in this model. These results demonstrate that GPVI is a receptor for fibrin and provide evidence that this interaction contributes to thrombus growth and stability.

  11. Fibrin activates GPVI in human and mouse platelets

    PubMed Central

    Alshehri, Osama M.; Montague, Samantha; Watson, Stephanie K.; Frampton, Jon; Bender, Markus; Watson, Steve P.

    2015-01-01

    The glycoprotein VI (GPVI)-Fc receptor γ (FcRγ) chain is the major platelet signaling receptor for collagen. Paradoxically, in a FeCl3 injury model, occlusion, but not initiation of thrombus formation, is delayed in GPVI-deficient and GPVI-depleted mice. In this study, we demonstrate that GPVI is a receptor for fibrin and speculate that this contributes to development of an occlusive thrombus. We observed a marked increase in tyrosine phosphorylation, including the FcRγ chain and Syk, in human and mouse platelets induced by thrombin in the presence of fibrinogen and the αIIbβ3 blocker eptifibatide. This was not seen in platelets stimulated by a protease activated receptor (PAR)-4 peptide, which is unable to generate fibrin from fibrinogen. The pattern of tyrosine phosphorylation was similar to that induced by activation of GPVI. Consistent with this, thrombin did not induce tyrosine phosphorylation of Syk and the FcRγ chain in GPVI-deficient mouse platelets. Mouse platelets underwent full spreading on fibrin but not fibrinogen, which was blocked in the presence of a Src kinase inhibitor or in the absence of GPVI. Spreading on fibrin was associated with phosphatidylserine exposure (procoagulant activity), and this too was blocked in GPVI-deficient platelets. The ectodomain of GPVI was shown to bind to immobilized monomeric and polymerized fibrin. A marked increase in embolization was seen following FeCl3 injury in GPVI-deficient mice, likely contributing to the delay in occlusion in this model. These results demonstrate that GPVI is a receptor for fibrin and provide evidence that this interaction contributes to thrombus growth and stability. PMID:26282541

  12. Demonstration of an instrumented patch

    NASA Astrophysics Data System (ADS)

    Martinez, M.; Renaud, G.; Backman, D.; Genest, M.; Delannoy, M.

    2007-04-01

    The primary objective of this study was to demonstrate the effectiveness of various strain measurement techniques at detecting the disbonding of a composite repair patch and then using this information to validate a new capacitance based disbond detection technique. The instrumented repair patch was parametrically designed with the help of Finite Element Analysis (FEA) software to have a stress concentration at its tip. This stress concentration was designed to produce a disbond during fatigue testing, without the need for the introduction of any foreign material to create an artificial disbond condition. The aluminum substrate was grit blasted and the instrumented patch was bonded using FM ®73 adhesive, and was cured following the recommendations of the manufacturer. The geometric characteristics of the patch followed standard repair guidelines for such variables as material selection, taper angles and loading conditions, with the exception of the area designed for premature disbond. All test specimens were inspected using non-destructive testing technique (ultrasound pulse echo) to guarantee that no disbonding had occurred during curing of the specimen. The specimens were placed under fatigue loading to induce a disbond condition between the aluminum substrate and the patch. The specimens were cyclically loaded and strain gauges bonded to strategic locations on the aluminum and composite patch surface to be able to measure changes in surface strains as the disbond progressed. A Digital Image Correlation (DIC) system was also used to measure full field strains over the gauge length of the coupon. The DIC results were compared with the strain gauge data and were used to provide a qualitative measure of the load transfer in the bonded specimen, which clearly demonstrated the change in surface strain that occurred as the composite patch disbonded from the aluminum substrate. Thermoelastic Stress Analysis (TSA) was also used to measure surface strains on the

  13. Sealants for Preventing and Arresting Pit-and-fissure Occlusal Caries in Primary and Permanent Molars.

    PubMed

    Wright, John T; Tampi, Malavika P; Graham, Laurel; Estrich, Cameron; Crall, James J; Fontana, Margherita; Gillette, E Jane; Nový, Brian B; Dhar, Vineet; Donly, Kevin; Hewlett, Edmond R; Quinonez, Rocio B; Chaffin, Jeffrey; Crespin, Matt; Iafolla, Timothy; Siegal, Mark D; Carrasco-Labra, Alonso

    2016-01-01

    National Health and Nutrition Examination Survey 2011-2012 data indicated that, in the United States, nearly onefourth of children and over one-half of adolescents experienced dental caries in their permanent teeth. The purpose of this review was to summarize the available clinical evidence regarding the effect of dental sealants for the prevention and management of pit-and-fissure occlusal carious lesions in primary and permanent molars, compared with a control without sealants, with fluoride varnishes, or with other head-to head comparisons. The authors included parallel and split-mouth randomized controlled trials that included at least 2 years of follow-up, which they identified using MEDLINE (via PubMed), Embase, LILACS, the Cochrane Central Register of Controlled Trials, and registers of ongoing trials. Pairs of reviewers independently conducted the selection of studies, data extraction, risk of bias assessments, and quality of the evidence assessments by using the Grading of Recommendations Assessment, Development and Evaluation approach. Of 2,869 records screened, the authors determined that 24 articles (representing 23 studies) proved eligible. Moderate-quality evidence suggested that participants who received sealants had a reduced risk of developing carious lesions in occlusal surfaces of permanent molars compared with those who did not receive sealants (odds ratio [OR], 0.15; 95% confidence interval [CI], 0.08-0.27) after 7 or more years of follow-up. When the authors compared studies whose investigators had compared sealants with fluoride varnishes, they found that sealants reduced the incidence of carious lesions after 7 or more years of follow-up (OR, 0.19; 95% CI, 0.07-0.51); however, this finding was supported by low-quality evidence. On the basis of the evidence, the authors could not provide a hierarchy of effectiveness among the studies whose investigators had conducted head-to-head comparisons. The investigators of 2 trials provided information

  14. PAH Concentrations Decline Following 2006 Ban on Coal-Tar-Based Pavement Sealants in Austin, Texas

    NASA Astrophysics Data System (ADS)

    Van Metre, P. C.; Mahler, B. J.

    2013-12-01

    Recent studies have concluded that coal-tar-based pavement sealants (CT sealants) are a major source of polycyclic aromatic hydrocarbons (PAHs) in non-industrial urban settings in the United States. In 2006, Austin, TX, became the first jurisdiction in the U.S. to ban the use of CT sealants. We evaluated PAH concentrations following the ban by analyzing sediment cores collected from Lady Bird Lake in 2012; Lady Bird Lake impounds the Colorado River in central Austin and receives runoff from much of the greater Austin area. The mean sum concentration of the 16 U.S. Environmental Protection Agency Priority Pollutant PAHs (∑PAH16) in one of two 2012 sediment cores analyzed for PAHs declined 75% from before 2006 (mean of 4 samples=8,090 μg kg-1) to 2012 (mean of 2 samples=2,030 μg kg-1), reversing a 40-year (1959-1999) upward trend in PAH concentrations that was previously documented. The downward trend in PAH concentrations in the seven uppermost 1 cm sampling intervals in the first 2012 core was statistically significant (r=0.93, p-value=0.002). Post-2008 PAH trends in the second 2012 core were similar (significant downward trend in the six uppermost 1 cm sampling intervals and mean 2012 ∑PAH16 of 2,390 μg kg-1); however, pre-2007 sediment did not appear to have been preserved in this core likely because of the effects of flooding on sediment deposition and mixing at this site--the largest flood on the Colorado River in Austin in 20 years was in 2007. On the basis of a comparison of lake-sediment PAH profiles to 22 PAH source profiles, the PAH loading to lake sediment continues to be dominated by CT sealants. The continued dominance of proportional PAH loading by CT sealants in spite of decreased concentrations since 2006 might be because legacy CT sealant and contaminated soils and sediments continue to yield PAHs to runoff. A previous study using source-receptor modeling concluded that CT sealants were the largest PAH source to 40 urban lakes studied in the

  15. Effectiveness of pit and fissure sealants bonded with different adhesive systems: a prospective randomized controlled trial.

    PubMed

    Erbas Unverdi, Gizem; Atac, Stephan Atilla; Cehreli, Zafer Cavit

    2016-11-30

    To evaluate and compare the clinical retention of a resin-based fissure sealant placed with an intermediate layer of etch-and-rinse (ER) or self-etch (SE) adhesives. Two hundred twenty-eight sealants were placed in 57 children with previously unsealed, caries-free permanent first molars, employing a split-mouth design. The teeth were randomized into four groups (n = 57 teeth/groups) according to the adhesive system placed under the tested sealant (Delton FS+; Dentsply). Group 1 (control): no bonding agent (conventional acid-etch sealant); group 2: prior enamel etch + ER adhesive (XP Bond; Dentsply); group 3: SE adhesive (Clearfil SE Bond; Kuraray) without prior etching; and group 4: prior enamel etch + SE adhesive (Clearfil SE Bond). Clinical assessments were performed according to modified USPHS criteria at 1, 3, 6, 12, 18, and 24 months. The data were analyzed statistically using Fisher's Exact test, the Kaplan-Meier analysis, and the Log-rank test. At 24 months, sealants bonded with XP Bond and Clearfil SE Bond with prior enamel etching showed similar retention rates (p > 0.05), and these rates were significantly better than the rates of the conventional sealant and Clearfil-SE groups (p < 0.05). There was no significant difference between the retention rates of the latter two groups (p > 0.05). The cumulative survival rates on palatal/buccal surfaces showed similar outcomes as with occlusal surfaces: XP Bond (94%), Clearfil SE Bond + acid-etch (94%), conventional sealant (52%), and Clearfil SE Bond only (37%). Application of the tested ER adhesive and the SE adhesive with enamel etching significantly improved the clinical retention of Delton-FS over the 24-month period. The use of a resin-based fissure sealant placed with ER or SE adhesive with prior acid-etching yielded better retention than the conventional sealant over the 24-month period.

  16. Effectiveness of a sealant compared with no sealant in preventing enamel demineralization in patients with fixed orthodontic appliances: a prospective clinical trial.

    PubMed

    O'Reilly, Maria T; De Jesús Viñas, Jaime; Hatch, John P

    2013-06-01

    In this study, we tested the efficacy of a tooth sealant polish (Biscover LV; Bisco, Schaumberg, Ill) to prevent enamel demineralization (white spot lesions) for the full duration of orthodontic treatment with fixed appliances. The trial design was an alternating-tooth split-mouth design. Patients starting treatment with bonded appliances in a private practice were enrolled. The 6 maxillary anterior teeth received the test sealant or no sealant. The nonblinded orthodontists visually examined the teeth immediately after debonding and rated the presence and severity of white spot lesions using a 4-point scale. The difference in incidence of white spot lesions on treated and control teeth was tested with multivariate binary logistic regression for repeated measures by using the generalized estimating equations approach. Sixty-five subjects were enrolled, and 3 were lost to follow-up, leaving 62 for analysis. There was a slightly lower incidence of white spot lesions on treated teeth (13.5%; 95% confidence interval, 8.6-18.4) compared with the control teeth (17.7%; 95% confidence interval, 12.4-23.7). This difference was statistically significant in the multivariate model (Wald chi-square, 5.07; df = 1; P = 0.024). The odds ratio was equal to 0.68 (95% confidence interval, 0.47-0.95) that treated teeth would show white spot lesions relative to the control teeth. White spot lesion severity was nearly the same for treated and control teeth (mean ± SD = 1.17 ± 0.47 and 1.20 ± 0.48, respectively; Wald chi-square, 3.03; df = 1; P = 0.082). No serious adverse effects were reported. The sealant did not prevent all white spot lesions for the full duration of treatment. The sealant demonstrated a clinically small but statistically significant ability to prevent white spot lesions. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  17. Fibrin Adhesive: Clinical Application in Coronary Artery Bypass Graft Surgery

    PubMed Central

    Fundaró, Pino; Velardi, Antonio R.; Santoli, Carmine

    1985-01-01

    Fibrin adhesive was used 72 times in a group of 67 patients undergoing elective coronary artery bypass graft surgery. The indications were prophylactic sealing of potential sources of bleeding, topical hemostasis (control of bleeding sites dangerous or difficult to suture), and fixation of the graft in the optimal position. The method of glue application under varying circumstances is described and the results are reported. This experience suggests that in some cases the glue expedites the operation and makes it safer. We conclude that the fibrin sealing represents a valid aid in coronary artery bypass graft surgery. PMID:15227018

  18. The effects of fibrin tissue adhesive on the middle ear.

    PubMed

    Katzke, D; Pusalkar, A; Steinbach, E

    1983-02-01

    This study investigated the effects of fibrin glue ('Tissucol', Immuno Pty. Ltd.) in the middle and inner ear. Small amounts of the adhesive were used in 36 operations performed on 18 rabbits. The light microscopic examination of these ears four, eight and 12 weeks after surgery showed that the adhesive was well tolerated and that it did not have any toxic effect on the middle ear or membranous labyrinth. The fibrin tissue adhesive can therefore safely be used to facilitate reconstructive middle-ear surgery and, with the aid of fascia, also for the closure of labyrinthine fistulae; or to achieve a definite seal of oval window niche after stapes surgery.

  19. In vitro study of Streptococcus mutans adhesion on composite resin coated with three surface sealants.

    PubMed

    Kim, Da Hye; Kwon, Tae-Yub

    2017-02-01

    Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans) on the dental composite resins coated with three commercial surface sealants. Composite resin (Filtek Z250) discs (8 mm in diameter, 1 mm in thickness) were fabricated in a mold covered with a Mylar strip (control). In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP). The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9). Group OG achieved the lowest water contact angle among all groups tested (p < 0.001). The cell surface of S. mutans tested showed hydrophobic characteristics. Group PoGo exhibited the greatest bacterial adhesion among all groups tested (p < 0.001). The sealant-coated groups showed statistically similar (groups PS and FP, p > 0.05) or significantly lower (group OG, p < 0.001) bacterial adhesion when compared with the control group. The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo.

  20. Effect of new light curing units on microleakage and microhardness of resin sealants.

    PubMed

    Bani, Mehmet; Tirali, Resmiye Ebru

    2016-01-01

    To determine new developed light curing units with shorter curing times effects on microleakage and microhardness values for resin fissure sealants. Resin filled sealant (UltraSeal-XT), resin unfilled sealant (Delton Type-II) and ormocer-based sealant (Admira-Seal) were light cured with a quartz-tungsten-halogen (QTH), two LED light and a high power LED. Two hundred and forty extracted human molars were randomly allocated into four groups according to used light-curing unit and three subgroups were formed for three different fissure sealant materials. Specimens were immersed in 0.5% basic fuchsin for 24 h, sectioned and examined under a stereomicroscope, and scored for marginal microleakage. Knoop hardness number (KHN) readings were measured after 48 h. Statistical analyses of test were found in significant difference both microleakage and microhardness values between the various light curing units. The time saving approaches in the curing light were determined higher microhardness, although it was found in higher microleakage.

  1. Effect of ozone pretreatment on the microleakage of pit and fissure sealants.

    PubMed

    Cehreli, S Burcak; Yalcinkaya, Zeynep; Guven-Polat, Gunseli; Cehreli, Zafer Cavit

    2010-01-01

    This study investigated the effect of ozone pretreatment on the microleakage and marginal integrity of pit and fissure sealants placed with or without a self-etch 6th generation adhesive. Freshly-extracted, human third molars were randomly assigned into two main groups (n = 48): Group A: Fissures were pretreated with ozone; Group B: Fissures were left untreated. The teeth were further randomly divided into two subgroups (n = 24/each) so that half of teeth were sealed with a conventional fissure sealant (Fissurit F, Voco, Germany), while the remaining half received the same sealant bonded with a self-etch adhesive (Clearfil Protect Bond, Kuraray, Japan). Following thermal cycling (1000X), the specimens were subjected to dye penetration within 0.5% basic fuchsin for 24h. The extent of dye penetration was measured by image analysis. Kruskal Wallis and Mann-Whitney U tests were used for statistical analysis of the data (p = 0.05). Two randomly-selected sections from each group were observed under SEM RESULTS: In all groups, ozone pretreatment significantly reduced the extent of microleakage (p < 0.001). SEM investigation demonstrated better adaptation of the sealants in ozone-pretreated groups. Clearfil Protect Bond did not improve the marginal seal of Fissurit F (p > 0.05). Ozone pretreatment favorably affected the marginal sealing ability of the tested fissure sealants.

  2. Evaluation of pumice, fissure enameloplasty and air abrasion on sealant microleakage.

    PubMed

    Blackwood, Julie A; Dilley, Diane C; Roberts, Michael W; Swift, Edward J

    2002-01-01

    The purpose of this in vitro study was to evaluate microleakage of pit and fissure sealants after using three different pit and fissure preparation techniques: (1) traditional pumice prophylaxis and acid etching, (2) fissure enameloplasty and acid etching and (3) air abrasion and acid etching. Sixty extracted third molars with no clinical evidence of caries were randomly divided into 3 groups of 20 each. Teeth were prepared using 1 of 3 occlusal surface treatments prior to placement of Delton opaque light-cured sealant. The teeth were thermocycled between 5 +/- 2 degrees C and 55 +/- 2 degrees C for 500 cycles with a dwell time of 30 seconds and then stored in 0.9% normal saline. All teeth were sealed apically and coated within 1.5 mm of the sealant margin with two layers of nail varnish. The teeth were immersed in a 1% solution of methylene blue for 24 hours to allow dye penetration into possible gaps between enamel and sealant. Three buccolingual cuts parallel to the long axis of the tooth were made yielding 4 sections and 6 surfaces per tooth for analysis. The surfaces were scored 0 to 3 for extent of microleakage using a binocular microscope at 25X magnification. Kruskal-Wallis and t tests revealed no significant difference in microleakage between the 3 fissure preparation methods prior to sealant placement. Neither air abrasion nor enameloplasty followed by acid etching produced significantly less microleakage than the traditional pumice prophylaxis with acid etching technique.

  3. Microleakage assessment of fissure sealant following fissurotomy bur or pumice prophylaxis use before etching.

    PubMed

    Bagherian, Ali; Akbari, Majid; Rezaeian, Mohsen; Ansari, Ghassem

    2013-09-01

    A prolonged life of fissure sealant has always been the target for preventing caries in vulnerable newly erupted teeth. The use of preparatory techniques including bur introduction to the fissures is considered among such improving steps. Ninety freshly extracted healthy maxillary premolar teeth were randomly selected for this investigation. Teeth were then divided into three fissure sealant preparatory groups of A: Fissurotomy bur + acid etch; B: Pumice prophylaxis + acid etch and C: Acid etch alone. Sealant was applied to the occlusal fissures of all specimens using a plastic instrument. This was to avoid any air trap under the sealant. Sample teeth were first thermocycled (1000 cycles, 20 s dwell time) and then coated with two layers of nail varnish leaving 2 mm around the sealant. This was then followed by immersion in basic fuchsin 3%. Processed teeth were sectioned longitudinally and examined under a stereomicroscope for microleakage assessment using a score of 0-3. Collected data was then subjected to Kruskall-Wallis Analysis of Variance and Mann-Whitney U-test. P > 0.05 was considered as significant. Teeth in fissurotomy bur and pumice prophylaxis groups had significantly reduced level of microleakage than those in acid etch alone (P = 0.005 and P = 0.003, respectively). Use of fissurotomy bur and pumice prophylaxis accompanied with acid etching appears to have a more successful reduction of microleakage than acid etch alone.

  4. Microleakage assessment of fissure sealant following fissurotomy bur or pumice prophylaxis use before etching

    PubMed Central

    Bagherian, Ali; Akbari, Majid; Rezaeian, Mohsen; Ansari, Ghassem

    2013-01-01

    Background: A prolonged life of fissure sealant has always been the target for preventing caries in vulnerable newly erupted teeth. The use of preparatory techniques including bur introduction to the fissures is considered among such improving steps. Materials and Methods: Ninety freshly extracted healthy maxillary premolar teeth were randomly selected for this investigation. Teeth were then divided into three fissure sealant preparatory groups of A: Fissurotomy bur + acid etch; B: Pumice prophylaxis + acid etch and C: Acid etch alone. Sealant was applied to the occlusal fissures of all specimens using a plastic instrument. This was to avoid any air trap under the sealant. Sample teeth were first thermocycled (1000 cycles, 20 s dwell time) and then coated with two layers of nail varnish leaving 2 mm around the sealant. This was then followed by immersion in basic fuchsin 3%. Processed teeth were sectioned longitudinally and examined under a stereomicroscope for microleakage assessment using a score of 0-3. Collected data was then subjected to Kruskall-Wallis Analysis of Variance and Mann-Whitney U-test. P > 0.05 was considered as significant. Results: Teeth in fissurotomy bur and pumice prophylaxis groups had significantly reduced level of microleakage than those in acid etch alone (P = 0.005 and P = 0.003, respectively). Conclusion: Use of fissurotomy bur and pumice prophylaxis accompanied with acid etching appears to have a more successful reduction of microleakage than acid etch alone. PMID:24348623

  5. Development of a Teat Bio-sealant and Evaluation of its Technological and Functional Properties.

    PubMed

    Serna-Cock, Liliana; Pabón-Rodríguez, Omar Vladimir

    2016-06-01

    A teat bio-sealant was developed using Weissella cibaria, and the bio-sealant's technological and functional properties were assessed. The development included four experimental phases that were analyzed using independent experimental designs. Initially, sterilized or pasteurized Aloe vera gels were used, and the effect of heat treatment was investigated. In the second phase, the effects of time, storage temperature, and addition of cryopreservatives on the viability of the probiotic were observed. The third phase consisted of evaluating the synergistic effects of the cryopreservatives. The fourth phase involved selecting a material that would provide viscosity to the teat sealant. Technological and functional properties were measured in terms of viability of W. cibaria, and antimicrobial activity against Staphylococcus aureus and Streptococcus agalactiae was also analyzed. A mixture of milk powder and glycerol preserved this antimicrobial activity. Pullulan provided greater viscosity and maintained the technological and functional properties of the bio-sealant for 29 days. This teat bio-sealant can be used as an alternative for the prevention of bovine mastitis.

  6. Dental Sealants: Knowledge, Value, Opinion, and Practice among Dental Professionals of Bathinda City, India

    PubMed Central

    Asawa, Kailash; Gupta, Vivek V.; Tak, Mridula; Nagarajappa, Ramesh; Chaturvedi, Pulkit; Bapat, Salil; Mishra, Prashant; Roy, Santanu Sen

    2014-01-01

    Objective. The purpose of the study was to assess the knowledge, value, opinion, and practice regarding use of dental sealants among private dental practitioners in Bathinda City, Punjab, India. Materials and Methods. A cross-sectional survey was conducted among all private dental practitioners in Bathinda City, Punjab. A self-administered structured questionnaire consisting of 28 items was used to assess their knowledge, value, opinion, and practice regarding dental sealants. One-way analysis of variance, independent sample t-test, and multivariate regression analysis were utilized for statistical analysis. Confidence level and level of significance were set at 95% and 5%, respectively. Results. The mean scores for knowledge, value, opinion, and practice were 41.8 ± 3.7, 18.7 ± 2.8, 18.1 ± 1.4, and 12.9 ± 2.3, respectively. Analysis revealed that qualification was statistically significant among all dependent variables (P ≤ 0.05); work experience was significantly associated with both knowledge and opinion means scores (P ≤ 0.05). Conclusion. The results suggest that dental practitioners had sufficient knowledge about dental sealants. They also acknowledge the importance of use of dental sealants. Practice of dental sealants in clinics was found adequate but they were not following the specific guidelines and standardized procedures. PMID:24818028

  7. Impact of adhesive and photoactivation method on sealant integrity and polymer network formation.

    PubMed

    Borges, Boniek Castillo Dutra; Pereira, Fabrício Lopes da Rocha; Alonso, Roberta Caroline Bruschi; Braz, Rodivan; Montes, Marcos Antônio Japiassú Resende; Pinheiro, Isauremi Vieira de Assunção; Santos, Alex José Souza dos

    2012-01-01

    We evaluated the influence of photoactivation method and hydrophobic resin (HR) application on the marginal and internal adaptation, hardness (KHN), and crosslink density (CLD) of a resin-based fissure sealant. Model fissures were created in bovine enamel fragments (n = 10) and sealed using one of the following protocols: no adhesive system + photoactivation of the sealant using continuous light (CL), no adhesive system + photoactivation of the sealant using the soft-start method (SS), HR + CL, or HR + SS. Marginal and internal gaps and KHN were assessed after storage in water for 24 h. The CLD was indirectly assessed by repeating the KHN measurement after 24 h of immersion in 100% ethanol. There was no difference among the samples with regard to marginal or internal adaptation. The KHN and CLD were similar for samples cured using either photoactivation method. Use of a hydrophobic resin prior to placement of fissure sealants and curing the sealant using the soft-start method may not provide any positive influence on integrity or crosslink density.

  8. Pit and Fissure Sealant Retention Following Air Abrasion Preparation with Bioactive Glass and Aluminum Oxide Particles.

    PubMed

    Khoroushi, Maryam; Eshghi, Alireza; Naderibeni, Fatemeh

    2016-09-15

    Alumina air abrasion is an alternative for acid-etch technique for tooth preparation before placement of a fissure sealant. The aim of this study was to compare the retention of sealants placed subsequent to air abrasion with alumina and bioactive glass (BAG) particles. Sixty-two 6-12 year old children were included in this study. Using a halfmouth design, the fissures were prepared using air abrasion with alumina particles on randomly assigned permanent mandibular or/and maxillary first molars on one side of the mouth (Group 1) and air abrasion with BAG on the contralateral side of the mouth (Group 2). Sealants were applied on 180 teeth, and were scored as missing, partially retained, and completely retained after three, six, nine and 12 months. Data were analyzed using Friedman and Wilcoxon tests (α=0.05). Sealant retention rates in the alumina group were higher than those in the BAG group at all time periods (P<0.001). Sealant retention after air abrasion with alumina particles was higher than BAG over 12 months.

  9. In vitro study of Streptococcus mutans adhesion on composite resin coated with three surface sealants

    PubMed Central

    Kim, Da Hye

    2017-01-01

    Objectives Although the coating of surface sealants to dental composite resin may potentially reduce bacterial adhesion, there seems to be little information regarding this issue. This preliminary in vitro study investigated the adhesion of Streptococcus mutans (S. mutans) on the dental composite resins coated with three commercial surface sealants. Materials and Methods Composite resin (Filtek Z250) discs (8 mm in diameter, 1 mm in thickness) were fabricated in a mold covered with a Mylar strip (control). In group PoGo, the surfaces were polished with PoGo. In groups PS, OG, and FP, the surfaces polished with PoGo were coated with the corresponding surface sealants (PermaSeal, PS; OptiGuard, OG; Fortify Plus, FP). The surfaces of the materials and S. mutans cells were characterized by various methods. S. mutans adhesion to the surfaces was quantitatively evaluated using flow cytometry (n = 9). Results Group OG achieved the lowest water contact angle among all groups tested (p < 0.001). The cell surface of S. mutans tested showed hydrophobic characteristics. Group PoGo exhibited the greatest bacterial adhesion among all groups tested (p < 0.001). The sealant-coated groups showed statistically similar (groups PS and FP, p > 0.05) or significantly lower (group OG, p < 0.001) bacterial adhesion when compared with the control group. Conclusions The application of the surface sealants significantly reduced S. mutans adhesion to the composite resin polished with the PoGo. PMID:28194363

  10. Sealant retention is better assessed through colour photographs than through the replica and the visual examination methods.

    PubMed

    Hu, Xuan; Fan, Mingwan; Rong, Wensheng; Lo, Edward C M; Bronkhorst, Ewald; Frencken, Jo E

    2014-08-01

    The aim of this study was to test the hypothesis that the colour photograph method has a higher level of validity for assessing sealant retention than the visual clinical examination and replica methods. Sealed molars were assessed by two evaluators. The scores for the three methods were compared against consensus scores derived through assessing retention from scanning electron microscopy images (reference standard). The presence/absence (survival) of retained sealants on occlusal surfaces was determined according to the traditional and modified categorizations of retention. Sensitivity, specificity, and Youden-index scores were calculated. Sealant retention assessment scores for visual clinical examinations and for colour photographs were compared with those of the reference standard on 95 surfaces, and sealant retention assessment scores for replicas were compared with those of the reference standard on 33 surfaces. The highest mean Youden-index score for the presence/absence of sealant material was observed for the colour photograph method, followed by that for the replica method; the visual clinical examination method scored lowest. The mean Youden-index score for the survival of retained sealants was highest for the colour photograph method for both the traditional (0.882) and the modified (0.768) categories of sealant retention, whilst the visual clinical examination method had the lowest Youden-index score for these categories (0.745 and 0.063, respectively). The colour photograph method had a higher validity than the replica and the visual examination methods for assessing sealant retention. © 2014 Eur J Oral Sci.

  11. [Public school programme for fissure sealants and its effect on the private demand for restorative dentistry for temporary teeth].

    PubMed

    Prados Atienza, María Belén; Muñoz Soto, Esther; Bravo, Manuel; González Rodríguez, María Paloma; Prados Sánchez, Estrella

    2006-11-30

    To analyse the effect of a public school odontological programme of fissure sealants on the private demand for restorative dentistry for temporary teeth. A longitudinal, comparative study was conducted. It had 2 groups, control and sealant, with 3 years monitoring. Santa Fe Health Area, concretely in the local districts (LD) of Santa Fe and Pinos Puente, Granada, Spain, starting in the school year 1996/1997. The sealant group was selected from the Santa Fe LD (which had a public programme of fissure sealants) (n=129); and the control group (n=120), from Pinos Puente LD. All the school students were examined (+ report issued) in the schools every 6 months for 3 years. The sealant group children received at the health centre fissure sealants in their first permanent molars. The restorations performed in temporary teeth for both groups were analysed (x+/-EE) during the study at 12, 24, and 36 month follow-up. RESULTS. The sealant group had a significantly greater increase in restorative treatment for temporary teeth (P< .05) than the Control group at all monitoring points. A public programme of fissure sealants raised private restorative treatment for temporary teeth.

  12. Effect of type and content of tackifier on adhesion of natural rubber and reclaimed natural rubber based sealant

    NASA Astrophysics Data System (ADS)

    Raethong, P.; Boonkerd, K.

    2017-07-01

    Adhesion property of natural rubber (NR) and reclaimed natural rubber (RNR) based sealant with concrete was studied here. The effect of tackifier type and loading on the tensile properties of the rubber based sealant sandwished between two flat cements was evaluated. There are three different tackifiers including Coumarone-indene resin (CI), petro resin (PE) and gum rosin (GR). The result initially showed that at the 20 phr of tackifier both NR and RNR sealant mixed with CI consumed the highest force to separate the rubber based sealant from the concrete. This might be due to the highest compatiblility between CI and rubber. Regardless of the tackifier type, all NR based sealants showed the cohesive failure while all RNR based sealants only showed the adhesive failure. Moreover, the NR based sealant seemed to be stronger than the RNR based one. When considering the effect of CI loading on the adhesion, it was shown that for both NR and RNR based sealents, the highest stress was observed when the rubber based sealant loaded with the 20 phr of CI.

  13. [Study of physical-chemical properties ot endodontic sealant Acroseal when different methods of root canal obturation].

    PubMed

    Ivanova, E V; Zubov, S V; Ivanchenko, O N; Poiurovskaia, I Ia; Rusanov, F S

    2009-01-01

    Results of the study of physical-chemical properties of new endodontic sealant Acrosil (Septodent, France) were presented. The results of all used in the experiment tests corresponded with the existing standards. The received data were compared with the corresponding tests of endodontic sealant AH-Plus (Dentsply, DeTrey, Germany) and were analyzed statistically. The comparison showed higher adhesion properties of Acrosil.

  14. Practice of Sealants and Preventive Resin Restorations Among Malaysian Dentists.

    PubMed

    Chin, Zhe W; Chong, Wai S; Mani, Shani A

    2016-01-01

    To assess the knowledge, attitude and utilisation regarding fissure sealants (FS) and preventive resin restorations (PRR) among Malaysian dentists. A questionnaire consisting of 35 questions was distributed by mail or an online survey to 425 registered dentists selected according to place of work by stratified random sampling. One hundred fifty-three dentists responded to the survey. A positive attitude towards FS and PRR was noted among most Malaysian dentists. About half of the respondents used FS/PRR occasionally (48.4%), while few (13.7%) applied them routinely. The majority of the dentists agreed that minimally invasive dentistry is important and FS are effective in caries prevention, using them on high caries-risk individuals. Most of the dentists used pumice or paste to clean teeth before placing FS/PRR. A significant number of dentists used a bonding agent prior to placing FS. Although only 57.5% dentists were aware of guidelines for FS use, most dentists agreed that guidelines are important. Although there was a positive attitude towards FS/PRR, few dentists applied them routinely. Some of the steps undertaken for placement of FS and PRR were outdated. Updating local guidelines for dentists to ensure uniform practice of FS and PRR is justified.

  15. A 2-year clinical evaluation of fluoride-containing pit and fissure sealants placed with an invasive technique.

    PubMed

    do Rego, M A; de Araújo, M A

    1996-02-01

    The aim of this study was to clinically evaluate fluoride-containing sealants in teeth subjected to minimal enamel reduction (preventive resin restorations). Two hundred fourteen sealants (109 FluroShield and 105 Delton Fluor) were applied in 153 teeth of 32 subjects. The sealants were evaluated for superficial irregularities, marginal adaptation, retention, and caries after 6, 12, 18, and 24 months. After 6, 12, and 18 months, the attendance at recall was 100.00%. After 24 months, 93.75% of subjects returned for reevaluation. Although total or partial loss of sealant occurred in a few instances, no occlusal caries was found in any tooth at any recall. No statistically significant differences in the results of the clinical evaluation were found between sealant in the maxillary and mandibular dentitions.

  16. Retention of fissure sealants in young permanent molars affected by dental fluorosis: a 12-month clinical study.

    PubMed

    Hasanuddin, S; Reddy, E R; Manjula, M; Srilaxmi, N; Rani, S T; Rajesh, A

    2014-10-01

    To evaluate and compare retention and caries occurance following placement of Clinpro and FUJI VII fissure sealants, by two different techniques simultaneously in unsealed, contralateral young permanent molars of 7- to 10-year-old children affected by mild to moderate dental fluorosis at various recall intervals of 1 week, 1, 3, 6 and 12 months. 80 schoolchildren with mild to moderate dental fluorosis were assigned to Group A and Group B with 40 children in each group. In Group A Clinpro fissure sealant and in Group B Fuji VII fissure sealant was used. In both the groups fissure sealants were applied by conventional fissure sealant technique (CST) on one side and enameloplasty sealant technique (EST) on the other side of the same arch. The applied fissure sealants were evaluated clinically for retention and caries incidence. Clinpro fissure sealant showed a retention rate of 95% when compared with Fuji VII (57.5%) at the end of 12 months, which was statistically significant. Regarding techniques, EST showed better results than CST in both the groups. Comparison of groups with respect to retention and techniques at different time periods was performed using Mann-Whitney U test (p < 0.05). Comparison of different time periods with respect to retention and technique in all the groups was performed using Wilcoxon matched pairs test by ranks (p < 0.05). Clinpro fissure sealant showed better retention at all treatment intervals, when compared with Fuji VII. Further follow-up is required to study the efficacy of the fissure sealant placement techniques.

  17. Comparison between visual clinical examination and the replica method for assessments of sealant retention over a 2-year period.

    PubMed

    Hu, Xuan; Chen, Xi; Ye, Lu; Fan, Ming-Wen; Huysmans, Marie-Charlotte; Frencken, Jo E

    2014-06-01

    To compare the levels of agreement and the survival rates of sealant retention for different sealing materials over a 2-year period assessed using the visual clinical examination and replica methods, sealant retention data were obtained by visual clinical examination and from replicas of the same sealed tooth at baseline and at 0.5-, 1- and 2-year evaluation points in 407 children and were compared for agreement using kappa coefficients. Survival curves of retained sealants on occlusal surfaces were created using modified categorisation (fully retained sealants and those having all pits and fissures partly covered with the sealant material versus completely lost sealants that included pit and fissure systems that had ≥1 pit re-exposed) according to the Kaplan-Meier method. The kappa coefficient for the agreement between both assessment methods over the three evaluation time points combined was 0.38 (95% confidence interval (CI): 0.35-0.41). More sealant retention was observed from replicas than through visual clinical examination. Cumulative survival curves at the three evaluation times were not statistically significantly higher when assessed from replicas (P=0.47). Using the replica method, more retained sealant material was observed than through visual clinical examination during the 2-year period. This finding did not result in a difference in the survival rates of sealants assessed by the two assessment methods. When replicas cast in die stone are used for assessing sealant retention, the level of reliability of the data is higher than that of data obtained through the commonly used visual clinical examination, particularly if such assessments are conducted over time.

  18. Long-term release of fluoride from fissure sealants-In vitro study.

    PubMed

    Kosior, Piotr; Dobrzyński, Maciej; Korczyński, Mariusz; Herman, Katarzyna; Czajczyńska-Waszkiewicz, Agnieszka; Kowalczyk-Zając, Małgorzata; Piesiak-Pańczyszyn, Dagmara; Fita, Katarzyna; Janeczek, Maciej

    2017-05-01

    The intensity of the cariostatic activity of fluoride ions can be attributed to their multidirectional influence on the caries process. They are an irreplaceable factor that helps sustain mineral balance of dental tissues, simultaneously demonstrating antibacterial properties. As a consequence, many manufacturers of fissure sealants include fluoride ions in their products. The aim of this in vitro study was to determine long-term fluoride release from four fissure sealants (Conseal F, Fissurit FX, Delton Fs+, Admira Seal). During a 14-week-long observation, all the materials showed a relatively constant level of F- release; however, it is crucial to mention that within the first 48h, the most significant increase in fluoride release was found for Fissurit and Delton sealants. Based on the overall assessment, the highest total amount of the released fluoride ions was observed for Delton, and the lowest level was reported for Admira Seal. Copyright © 2017 Elsevier GmbH. All rights reserved.

  19. Glass-ceramic sealant for solid oxide fuel cells application: Characterization and performance in dual atmosphere

    NASA Astrophysics Data System (ADS)

    Sabato, A. G.; Cempura, G.; Montinaro, D.; Chrysanthou, A.; Salvo, M.; Bernardo, E.; Secco, M.; Smeacetto, F.

    2016-10-01

    A glass-ceramic composition was designed and tested for use as a sealant in solid oxide fuel cell (SOFC) planar stack design. The crystallization behaviour was investigated by calculating the Avrami parameter (n) and the activation energy for crystallization (Ec) was obtained. The calculated values for n and Ec were 3 and 413.5 kJ/mol respectively. The results of thermal analyses indicate that this composition shows no overlap between the sintering and crystallization stages and thus an almost pore-free sealant can be deposited and sintered at 850 °C in air for 30 min. A gas tightness test has been carried out at 800 °C for 1100 h in dual atmosphere (Ar-H2 and air) without recording any leakage. Morphological and crystalline phase analyses were conducted prior and following tests in dual atmospheres in order to assess the compatibility of the proposed sealant with the metallic interconnect.

  20. An in-vitro evaluation of mechanical and esthetic properties of orthodontic sealants

    PubMed Central

    Premaraj, Thyagaseely Sheela; Rohani, Nima; Covey, David; Premaraj, Sundaralingam; Hua, Yi; Watanabe, Hidehiko

    2014-01-01

    Objective: To evaluate mechanical and esthetic Properties of two commercially available orthodontic sealants: Opal®Seal (OS) and L.E.D. Pro Seal (PS). Materials and Methods: Discs of each sealant were prepared to test the following properties: Micro hardness, wear resistance and color stability. Samples were randomly selected after the wear test for SEM imaging to analyze surface morphology. Results: OS was significantly harder than PS (P < 0.001). PS was significantly more wear resistant than OS (P < 0.05). PS showed a greater ∆E*ab (increased staining) when placed in wine or coffee showing a significant difference (P < 0.05). SEM showed particle size, shape and distribution were different for PS and OS reflecting the pattern seen on wear surfaces. Conclusion: Both orthodontic sealants are beneficial for protecting enamel. However with better wear properties PS was superior in resisting mechanical stresses. OS was more color stable. PMID:25512729

  1. Modification of silicone sealant to improve gamma radiation resistance, by addition of protective agents

    NASA Astrophysics Data System (ADS)

    González-Pérez, Giovanni; Burillo, Guillermina

    2013-09-01

    Poly (dimethylsiloxane) (PDMS) sealant (SS) was modified with the addition of different protective compounds to conserve its physical-chemical properties during gamma irradiation. 2-Vinyl naphthalene (2-VN), bisphenol-A (BPA) and poly (vinyl carbazole) (PVK) were used to evaluate radiation protection through the crosslinking effect of radiation. The samples were irradiated with doses from 100 kGy to 500 kGy at room temperature in air, with a 60Co gamma source, and the changes in molecular weight, thermal behavior, elastic properties and infrared spectra (FTIR-ATR) absorbance analysis were determined. The molecular weight of unmodified silicone sealant increases with the absorbed dose because of crosslinking as predominant effect. However, the crosslinking effect was inhibited with the addition of protective agent due to the aromatic compounds present. Modified silicone sealant films present better radiation resistance than unmodified system.

  2. Enhanced Neurite Growth from Mammalian Neurons in Three-Dimensional Salmon Fibrin Gels

    PubMed Central

    Ju, Yo-El; Janmey, Paul A.; McCormick, Margaret; Sawyer, Evelyn S.; Flanagan, Lisa A.

    2007-01-01

    Three-dimensional fibrin matrices have been used as cellular substrates in vitro and as bridging materials for central nervous system repair. Cells can be embedded within fibrin gels since the polymerization process is non-toxic, making fibrin an attractive scaffold for transplanted cells. Most studies have utilized fibrin prepared from human or bovine blood proteins. However, fish fibrin may be well suited for neuronal growth since fish undergo remarkable central nervous system regeneration and molecules implicated in this process are present in fibrin. We assessed the growth of mammalian central nervous system neurons in bovine, human, and salmon fibrin and found that salmon fibrin gels encouraged the greatest degree of neurite (dendrite and axon) growth and were the most resistant to degradation by cellular proteases. The neurite growth-promoting effect was not due to the thrombin used to polymerize the gels or to any copurifying plasminogen. Co-purified fibronectin partially accounted for the effect on neurites, and blockade of fibrinogen/fibrin-binding integrins markedly decreased neurite growth. Anion exchange chromatography revealed different elution profiles for salmon and mammalian fibrinogens. These data demonstrate that salmon fibrin encourages the growth of neurites from mammalian neurons and suggest that salmon fibrin may be a beneficial scaffold for neuronal regrowth after CNS injury. PMID:17258313

  3. Fibrin glue improves the therapeutic effect of MSCs by sustaining survival and paracrine function.

    PubMed

    Kim, Inok; Lee, Sung Koo; Yoon, Jung In; Kim, Da Eun; Kim, Mihyung; Ha, Hunjoo

    2013-11-01

    Fibrin glue has been widely investigated as a cell delivery vehicle for improving the therapeutic effects of mesenchymal stem cells (MSCs). Implanted MSCs produce their therapeutic effects by secreting paracrine factors and by replacing damaged tissues after differentiation. While the influence of fibrin glue on the differentiation potential of MSCs has been well documented, its effect on paracrine function of MSCs is largely unknown. Herein we investigated the influence of fibrin glue on the paracrine effects of MSCs. MSCs were isolated from human adipose tissue. The effects of fibrin glue on survival, migration, secretion of growth factors, and immune suppression of MSCs were investigated in vitro. MSCs in fibrin glue survived and secreted growth factors such as the vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) over 14 days. VEGF and immune modulators, including the transforming growth factor (TGF)-β1 and prostaglandin E2, secreted from MSCs in fibrin glue significantly increased under inflammatory conditions. Thus, MSCs in fibrin glue effectively suppressed immune reactions. In addition, fibrin glue protected the MSCs from oxidative stress and prevented human dermal fibroblast death induced by exposure to extreme stress. In contrast, MSCs within fibrin glue hardly migrated. These results suggest that fibrin glue may sustain survival of implanted MSCs and their paracrine function. Our results provide a mechanistic data to allow further development of MSCs with fibrin glue as a clinical treatment.

  4. Micromachined patch-clamp apparatus

    SciTech Connect

    Okandan, Murat

    2012-12-04

    A micromachined patch-clamp apparatus is disclosed for holding one or more cells and providing electrical, chemical, or mechanical stimulation to the cells during analysis with the patch-clamp technique for studying ion channels in cell membranes. The apparatus formed on a silicon substrate utilizes a lower chamber formed from silicon nitride using surface micromachining and an upper chamber formed from a molded polymer material. An opening in a common wall between the chambers is used to trap and hold a cell for analysis using the patch-clamp technique with sensing electrodes on each side of the cell. Some embodiments of the present invention utilize one or more electrostatic actuators formed on the substrate to provide mechanical stimulation to the cell being analyzed, or to provide information about mechanical movement of the cell in response to electrical or chemical stimulation.

  5. Microleakage, adaptation ability and clinical efficacy of two fluoride releasing fissure sealants.

    PubMed

    Marković, Dejan; Petrović, Bojan; Perić, Tamara; Blagojević, Duska

    2012-04-01

    Retention of fissure sealants and good adaptation to enamel are essential for their success. Fluoride releasing resin-based materials are widely accepted for pit and fissure sealing, but newly designed glass ionomers can serve as a good alternative. The aim of this study was to evaluate microleakage and sealing ability in vitro, and to clinically assess two fluoride releasing fissure sealants. The sample for experimental study consisted of 20 freshly extracted intact human third molars, divided in two experimental groups according to the sealing material: fluoride releasing resin-based (Heliosel F) and glass ionomer (Fuji Triage) material. Digital images and scanning electron microscope were used to assess microleakage and adaptation ability. Sample for clinical study consisted of 60 children, aged 6-8 years, with high caries risk, divided in two groups according to the sealant material. Fissure sealant was applied to all erupted, caries-free first permanent molars. Sealants were evaluated after 3, 6 and 12 months using modified Ryge criteria for retention, marginal adaptation, colour match, surface smoothness and caries. Microleakage was detected in more than half of the specimen, without significant differences between the two groups (p > 0.05). Both materials exhibited acceptable sealing ability. Complete retention at the end of the observation period was 81.8% for resin-based, and 21.1% for glass-ionomer fissure sealant (p < 0.001). The presence of caries in sealed molars has been detected in one patient in both groups. During the 12-month observation period, Helioseal F demonstrated better retention, marginal adaptation and surface smoothness (p < 0.001). There were no differences between the two materials regarding caries and color match (p > 0.05). Both tested materials demonstrate satisfactory clinical and caries prophylactic characteristics that justify their use in contemporary preventive dentistry.

  6. Dental sealants and flowable composite restorations and psychosocial, neuropsychological, and physical development in children.

    PubMed

    Maserejian, Nancy N; Shrader, Peter; Trachtenberg, Felicia L; Hauser, Russ; Bellinger, David C; Tavares, Mary

    2014-01-01

    Dental sealant materials may intraorally release their components, including bisphenol-A (BPA), but long-term health effects are uncertain. The New England Children's Amalgam Trial (NECAT) found that composite restorations were associated with psychosocial, but not neuropsychological or physical, outcomes. The previous analysis did not consider sealants and preventive resin restorations (PRRs), which were routinely placed. The purpose of this analysis was to examine sealant/PRR exposure in association with psychosocial and other health outcomes. NECAT recruited 534 six- to 10-year-olds and provided dental care during a five-year follow-up. Annually, examiners conducted psychosocial and neuropsychological tests and measured body mass index (BMI) and fat percentage (BF%). Associations between surface years (SY) of sealants/PRRs and outcomes were tested using multivariable models. Cumulative exposure level to sealants and/or PRRs was not associated with psychosocial assessments (eg, total problems: Child Behavior Checklist, 10-SY β=-0.2 ± 0.3, P=.60) or neuropsychological tests (eg, full-scale IQ, 10-SY β=0.1 ± 0.2, P=.60). There were no associations for changes in BMI-for-age z-score (P=.40), BF% (girls 10-SY β=-0.2 ± 0.3; boys 10-SY β=-0.1 ± 0.3), or menarche (10-SY hazard ratio=0.91, 95% confidence interval=0.83-1.01, P=.08). This study showed no associations between exposure level of dental sealants or PRRs and behavioral, neuropsychological, or physical development in children over 5-years.

  7. Dental Sealants and Flowable Composite Restorations and Psychosocial, Neuropsychological, and Physical Development in Children

    PubMed Central

    Maserejian, Nancy N.; Shrader, Peter; Trachtenberg, Felicia L.; Hauser, Russ; Bellinger, David C.; Tavares, Mary

    2016-01-01

    Purpose Dental sealant materials may release their components, including bisphenol-A (BPA), intra-orally, but long-term health effects are uncertain. The New England Children’s Amalgam Trial (NECAT) found that composite restorations were associated with psychosocial, but not neuropsychological or physical, outcomes. The previous analysis did not consider sealants and preventive resin restorations (PRRs), which were routinely placed during NECAT. This analysis examines sealant/PRR exposure in association with psychosocial and other health outcomes. Methods NECAT recruited 534 children aged 6–10 years and provided dental care during 5-year follow-up. Annually, examiners conducted psychosocial and neuropsychological tests, and measured body mass index (BMI) and fat percentage (BF%). Associations between surface-years (SY) of sealants/PRRs and outcomes were tested using multivariable models. Results Cumulative exposure level to sealants and/or PRRs was not associated with psychosocial assessments (e.g. total problems: Child Behavior Checklist, 10-SY β=−0.2, SE=0.3, P=0.6) or neuropsychological tests (e.g. full-scale IQ, 10-SY β=0.1, SE=0.2, P=0.6). There were no associations for changes in BMI-for-age z-score (P=0.4), BF% (girls 10-SY β= −0.2 SE=0.3; boys 10-SY β= −0.1 SE=0.3), or menarche (10-SY hazard ratio=0.91, 95%CI 0.83–1.01, P=0.08). Conclusions This analysis showed no significant associations between exposure level of dental sealants or PRRs and behavioral, neuropsychological, or physical development in children during 5-year follow-up. PMID:24717713

  8. A Chitosan-Based Sinus Sealant for Reduction of Adhesion Formation in Rabbit and Sheep Models

    PubMed Central

    Medina, Jennifer G.; Steinke, John W.; Das, Subinoy

    2013-01-01

    Objective Chronic sinusitis is the most prevalent chronic disease in the United States in adults aged 18 to 44 years, with approximately 250,000 operations performed annually. Although often successful, sinus surgery fails in greater than 15% of patients. Adhesion formation is a common complication and cause for subsequent revision surgery. Here, the authors evaluate a sprayable chitosan/starch-based sinus sealant and demonstrate its ability to reduce adhesion formation both in vitro and in 2 animal models. Study Design Randomized, controlled, animal trials. Setting Academic medical center (fibroblast experiments) and animal laboratories (sheep and rabbit studies). Subjects and Methods This sinus sealant was applied to human cultured fibroblasts obtained from surgically removed polyps to examine its ability to inhibit fibroblast migration and proliferation. The sinus sealant was applied to New Zealand White rabbits (n = 20) in an established cecal-sidewall abrasion model and to sheep (n = 10) in a sinus surgical adhesion model to examine its ability to reduce adhesion formation. Results This sinus sealant inhibited migration and proliferation of human cultured fibroblasts and reduced the total adhesion score from 4.9 to 0.3 for a total reduction of 94% (95th percentile confidence interval [CI], 78%, 100%; P < .001) in a well-established rabbit cecal-sidewall model commonly used for adhesion testing. Moreover, this sealant reduced adhesion formation from 80% to 10% for a total reduction of 70% (95th percentile CI, 57%, 93%; P = .003) in a sheep sinus adhesion surgical model. Conclusion This chitosan-based sealant demonstrates promise for reducing adhesion formation in sinus surgery. PMID:22492298

  9. Influence of tooth-polishing pastes and sealants on DIAGNOdent values.

    PubMed

    Hosoya, Yumiko; Matsuzaka, Kenichi; Inoue, Takashi; Marshall, Grayson W

    2004-09-01

    The purpose of this study was to investigate the influence of tooth-polishing pastes and sealants on values obtained with a caries diagnostic system based on detection of caries-associated fluorescence (DIAGNOdent, KaVo). Ten tooth-polishing pastes and four dentifrices were measured alone, and it was shown that products containing pumice gave high DIAGNOdent values. The deepest occlusal pits of 20 extracted sound premolars (12 unsealed teeth, 8 sealed teeth) were measured before polishing, after rotating-brush polishing with pumice-containing tooth-polishing paste, and after final rotating-brush polishing with water in this in vitro study. In the clinical phase, the deepest occlusal pits of 21