Application Of Sealant Research Articles

Application of Fibrin Sealant in the Treatment of Root Coverage Procedure - A Case Report

Application of Fibrin Sealant in the Treatment of Root Coverage Procedure - A Case Report

Retention and Effectiveness of School-based Dental Sealant Programs in Lucknow – A Randomized Controlled Trial

Background: Pit-and-fissure sealants, particularly the resin-based type, are widely used as the most efficient technique for preventing caries on the occlusal surfaces of permanent molars. School-based dental sealant (SBDS) program is a system where sealants are applied to the children in their schools with the primary aim to certify and safeguard the permanent molars that are sealed at the earliest after eruption. Aim: The aim of this study was to evaluate the retention and effectiveness of SBDS Programs in Lucknow, UP. Materials and Methods: A split-mouth randomized controlled trial was conducted among 6-year-old school-going children of Lucknow, UP. The study was carried out by a single trained and calibrated investigator who recorded the dentition status. The investigator interviewed the participants using a pro forma and examined the subjects included in the study. The sealant was applied to one tooth in the pair of fully erupted permanent first molars, and no treatment was done on the other side. Results: The proportion of total retention after 1½ years was significantly higher in mandibular as compared with maxillary molars (Z = 2.04; P = 0.04). The risk of having caries was 3.52 times more among children with no treatment as compared to children with treatment (odds ratio [OR] – 3.52 [1.01, 13.11]; P = 0.04; statistically significant). The association between survival rate of sealant and International Caries Detection and Assessment System codes (0 and 1–2) as well as that between retention of sealant and caries status was statistically significant (P < 0.01 and 0.00001, respectively). The risk of having caries was 1.28 times more among males as compared to females (OR – 1.28 [0.38, 4.24]; P = 0.06), 1.61 times for sugar exposure (OR – 1.61 [0.53, 6.19]; P = 0.53; nonsignificant). Conclusion: Sealant application proved to be an efficient method in preventing dental caries development; hence, SBDS programs, wherein the sealants were placed at school, were highly efficacious and acceptable in the vulnerable populace.

A tough bioadhesive hydrogel supports sutureless sealing of the dural membrane in porcine and ex vivo human tissue.

Complete sequestration of central nervous system tissue and cerebrospinal fluid by the dural membrane is fundamental to maintaining homeostasis and proper organ function, making reconstruction of this layer an essential step during neurosurgery. Primary closure of the dura by suture repair is the current standard, despite facing technical, microenvironmental, and anatomic challenges. Here, we apply a mechanically tough hydrogel paired with a bioadhesive for intraoperative sealing of the dural membrane in rodent, porcine, and human central nervous system tissue. Tensile testing demonstrated that this dural tough adhesive (DTA) exhibited greater toughness with higher maximum stress and stretch compared with commercial sealants in aqueous environments. To evaluate the performance of DTA in the range of intracranial pressure typical of healthy and disease states, ex vivo burst pressure testing was conducted until failure after DTA or commercial sealant application on ex vivo porcine dura with a punch biopsy injury. In contrast to commercial sealants, DTA remained adhered to the porcine dura through increasing pressure up to 300 millimeters of mercury and achieved a greater maximum burst pressure. Feasibility of DTA to repair cerebrospinal fluid leak in a simulated surgical context was evaluated in postmortem human dural tissue. DTA supported effective sutureless repair of the porcine thecal sac in vivo. Biocompatibility and adhesion of DTA was maintained for up to 4 weeks in rodents after implantation. The findings suggest the potential of DTA to augment or perhaps even supplant suture repair and warrant further exploration.

Micro-Scale Abrasive Wear Resistance of a Nanoceramic Sealant Applied on Galvanized Low Carbon Steel

The idea for this work came from a market need to obtain coatings or sealants that would extend the useful life of metallic materials in applications that involve exposure to corrosive environments. The main objective of the nanoceramic sealant studied in this work is to extend the life of metallic fasteners. To evaluate the performance of the sealant from other perspectives, microstructural analysis, adhesion test, micro-scale abrasive wear tests and corrosion test were carried out. These tests were performed on samples coated only with white zinc, which is commonly used in the fastener industry, and on samples coated with white zinc followed by application of the nanoceramic sealant. The application of the nanoceramic sealant contributed to the improvement of corrosion resistance and reduction of the corrosion rate. The corrosion rate of the sample coated with the sealant reduced by 62.2% when compared to the sample that only went through the white zinc coating process. The coating showed low adhesion to the substrate with the presence of severe delamination and microcracks. This feature contributed to the low wear resistance presented by the coating under the conditions studied in this work. Less attention, compared to studies involving corrosion resistance, has been given to wear resistance in the fastener industry. The results obtained in this paper show that the study of tribological behavior is an important factor in increasing the efficiency of fasteners applied in harsh environments.

Comparative Analysis of Techniques for Pit and Fissure Sealant Application to Reduce Microleakage.

Introduction In modern dentistry, the focus is more on preventing caries than on treating it, which helps preserve the tooth structure. Pit and fissure sealants (PFS) are the most effective methods for providing a mechanical barrier and avoiding the accumulation of dental plaque in deep pits and fissures, thereby preventing occlusal caries. The present study was conducted to compare the efficiency of dentin bonding agents (DBA) with or without fissurotomy in reducing microleakage before PFS placement. Materials and methods A total of 48 freshly extracted premolars were randomly divided into four groups as follows: Group 1, the conventional technique of PFS (Clinpro, 3M ESPE sealant); Group 2, fissurotomy performed before PFS placement; Group 3, Scotchbond Universal Adhesive (3M ESPE DBA) applied before PFS placement; and Group 4, fissurotomy along with DBA was used before PFS placement. The teeth were subjected to thermocycling followed by dye penetration using a 1% solution of methylene blue for 24 hours. All teeth were then assessed for microleakage by a qualitative method using a stereomicroscope at 40X and depth of dye penetration by image analysis. The Kruskal-Wallis test followed by Dunn's test was used for intergroup comparisons of microleakage scores, and ANOVAfollowed by Tukey's test was used for intergroup comparisons of the depth of dye penetration. These analyses were conducted using statistical software (SPSS version 22, Chicago, IL, USA). Results Statistically significant differences were observed between the groups in terms of the microleakage scores and depth of dye penetration (p<0.05). The group 4 showed a minimum microleakage score (0.50±0.52), and maximum scores were observed in Group 1 (2.16±0.71). Group 2 showed insignificant differences with groups 3 and 4 for depth of dye penetration (p>0.05). Statistically significant differences were observed between groups 1 and 2, groups 1 and 4, and groups 3 and 4 for the microleakage score (p<0.05). Conclusion Fissurotomy with or without DBA significantly reduced microleakage before the PFS placement. Prior use of fourth-generation DBA significantly reduced microleakage compared with PFS placement without the use of DBA.

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

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

Subfascial drains are safe and effective in preventing postoperative cerebrospinal fluid leaks after intradural spine tumor surgery.

Delayed cerebrospinal fluid (CSF) leaks are a known complication following intradural spinal tumor surgery. The placement of subfascial drains in these patients undergoing requisite intradural surgery is controversial. Here, we demonstrated that placing a subfascial drain on partial suction for 48 h, with early ambulation, proved to be safe and effective in preventing early/delayed recurrent CSF fistulas. Medical records of 17 patients undergoing surgery for intradural spinal tumors over a 30-month were reviewed. All patients underwent intradural tumor resection followed by primary dural closure, placement of Gelfoam in a non-compressive fashion, application of fibrin sealant, and utilization of a subfascial drain placed on partial suction for 48 h postoperatively. Patients are mobilized the morning following surgery. We tracked the incidence of postoperative recurrent CSF leaks, over drainage, infection, wound dehiscence, pseudo meningocele formation, and the reoperation rate. For the 17 patients, our programmed average utilization of subfascial drains was 48 h. Moreover, the average drain output was 165 mL. Over the 1-year follow-up period, no patient developed a recurrent early/ delayed CSF leak, there were no wound complications, nor need for revision surgery. Utilizing subfascial drains on partial suction following the resection of intradural spinal tumors with primary dural closure proved to be safe and effective.

Removal or preservation in place? A review of the conservation management options for asbestos cement sheeting in heritage properties

PurposeInvented in late 1890s, asbestos cement sheeting rose to prominence during the post-Second World War period as a building material for low-cost housing by state housing commissions and low-income families (“fibro homes”). The adverse health effects of asbestos fibres in the building industry and home renovation activities are well documented. Fibro homes of the 1950s and 1960s are increasingly coming under the gaze of heritage studies, which brings to the fore the question of how to deal with the asbestos cement sheeting most are clad with.Design/methodology/approachThis paper provides the first systematic review to assess the literature (126 papers were identified in Google Scholar and scanned for content) on the conservation management of asbestos cement sheeting in heritage properties.FindingsOverall, engagement with the conservation management of asbestos cement sheeting in heritage properties was low, with only two sources dealing with asbestos cement sheeting in any level of detail. The studies note that if asbestos cement sheeting is in good condition, it should be left alone. Numerous conservation and repair options do exist, in particular the application of (coloured) sealants that extend the life of asbestos cement sheets and asbestos cement roofing.Originality/valueThis paper represents the first systematic review to assess conservation management options for asbestos cement sheeting in heritage properties.

Time of Application of Fluoride Varnish versus Resin-Based Fissure Sealant in Newly Erupted Permanent Molars in Group of Egyptian Children: A Randomized Clinical Trial

Time of Application of Fluoride Varnish versus Resin-Based Fissure Sealant in Newly Erupted Permanent Molars in Group of Egyptian Children: A Randomized Clinical Trial

Attitudes of general dental practitioners toward preventive approach in pediatric patients: A cross-sectional survey

Abstract Objective: This cross-sectional survey aimed to assess the attitudes and practices of general dental practitioners regarding a preventive approach in pediatric patients. Methods: This cross-sectional survey involved 279 general dental practitioners and employed a structured questionnaire comprising multiple items to assess their attitudes and practices related to a preventive approach in pediatric patients and data were analyzed using the descriptive statistics and Chi-square tests. Results: The survey revealed that 60.1% of pediatric patients visited the clinic frequently and 71.0% were treated directly by the dentists. A preventive approach was common (69.2%) among practitioners. Prescription practices showed that 57.1% of dentists prescribed a specified amount of fluoridated toothpaste and 62.5% preferred fluoride gel over varnish. Nonfluoride remineralizing agents were preferred by 60.0% of dentists. Glass ionomer cement (66.7%) was preferred for pit fissure sealant applications. Conclusion: The survey indicates that general dental practitioners have a positive attitude toward preventive care in pediatric patients. However, further education and knowledge dissemination are needed to enhance their understanding and confidence.

Effect of Different Protocols on The Microleakage of A Fissure Sealant Applied During Saliva Contamination

Statement of the problem: Saliva contamination during sealant application has negative consequences that affects long-term success including retention and caries progression. Objective: The effect of different protocols to minimize the effect of saliva contamination on the microleakage of a resin based fissure sealant material (3M Clinpro™ Sealant) was investigated. Materials &amp; Methods: Extracted human third molars (n=160) were used: Group A. Etch-and-rinse adhesive (Prime &amp; Bond One Select); Group B. Selfetching adhesive (Clearfil SE Bond). These comprised eight paired subgroups where enameloplasty was done (or not), saliva contamination occurred before (or after) the polymerization of the bonding agent and the entire procedure was repeated (or not) following saliva contamination before the sealant application. Following thermocycling, the samples were immersed in basic fuchsin, sectioned, and dye penetration was quantitatively assessed with ImageJ. The data were statistically analyzed (α=0.05). Results: Significantly less microleakage was observed in Group A (P=0.000). Intergroup differences with respect to the effect of adhesive type, enameloplasty, saliva contamination occurred after the polymerization of the bonding agent and repeating the entire procedure following saliva contamination were significant (p&lt;0.05, each). Enameloplasty reduced microleakage in subgroups of A and B (P=0.002 and P=0.014, respectively). Saliva contamination after the polymerization of the bonding agent resulted in less microleakage in subgroups of A and B (P=0.01 and P=0.002, respectively). Less microleakage was observed in subgroups of A and B where the entire procedure was repeated following saliva contamination (P=0.000, both). Conclusions: The use of etch-and-rinse adhesive, enameloplasty, saliva contamination occurring after the polymerization of the bonding agent and repeating the entire procedure reduced microleakage of the fissure sealant applied during saliva contamination.

Study on corrosion resistance of passive film promoted by natural rosin-based passive sealant

An eco-friendly Rosin-based passive sealant is prepared, which can seal the micropores and repair the passive film in one-step. Sealing performance of sealants and the growth kinetics of the passive film were analyzed by 3D-XRT tomography, Electrochemistry and XPS. The results showed that the permeation depth of sealant reached more than 150 μm, and the natural rosin effectively prolonged the loss time of sealant. The phosphate conversion layer at the passive film/sealant interface changes the semiconductor properties of the passive film. After immersion for 360 h in 3.5 wt% NaCl solution, the amount of Fe2O3 and Cr2O3 in the passive film increased by 34 % and 20 %, respectively, and the film thickness increased by 257.9 %. Rosin-based passive sealant can directly inhibit the diffusion rate of defects in passive film. This study provides a new theoretical support for the application of rosin sealant.

Combining adhesive and nonadhesive injectable hydrogels for intervertebral disc repair in an ovine discectomy model.

Intervertebral disc (IVD) disorders (e.g., herniation) directly contribute to back pain, which is a leading cause of global disability. Next-generation treatments for IVD herniation need advanced preclinical testing to evaluate their ability to repair large defects, prevent reherniation, and limit progressive degeneration. This study tested whether experimental, injectable, and nonbioactive biomaterials could slow IVD degeneration in an ovine discectomy model. Ten skeletally mature sheep (4-5.5 years) experienced partial discectomy injury with cruciate-style annulus fibrosus (AF) defects and 0.1 g nucleus pulposus (NP) removal in the L1-L2, L2-L3, and L3-L4 lumbar IVDs. L4-L5 IVDs were Intact controls. IVD injury levels received: (1) no treatment (Injury), (2) poly (ethylene glycol) diacrylate (PEGDA), (3) genipin-crosslinked fibrin (FibGen), (4) carboxymethylcellulose-methylcellulose (C-MC), or (5) C-MC and FibGen (FibGen + C-MC). Animals healed for 12 weeks, then IVDs were assessed using computed tomography (CT), magnetic resonance (MR) imaging, and histopathology. All repaired IVDs retained ~90% of their preoperative disc height and showed minor degenerative changes by Pfirrmann grading. All repairs had similar disc height loss and Pfirrmann grade as Injury IVDs. Adhesive AF sealants (i.e., PEGDA and FibGen) did not herniate, although repair caused local endplate (EP) changes and inflammation. NP repair biomaterials (i.e., C-MC) and combination repair (i.e., FibGen + C-MC) exhibited lower levels of degeneration, less EP damage, and less severe inflammation; however, C-MC showed signs of herniation via biomaterial expulsion. All repair IVDs were noninferior to Injury IVDs by IVD height loss and Pfirrmann grade. C-MC and FibGen + C-MC IVDs had the best outcomes, and may be appropriate for enhancement with bioactive factors (e.g., cells, growth factors, and miRNAs). Such bioactive factors appear to be necessary to prevent injury-induced IVD degeneration. Application of AF sealants alone (i.e., PEGDA and FibGen) resulted in EP damage and inflammation, particularly for PEGDA IVDs, suggesting further material refinements are needed.

The effect of different deproteinization agents on microleakage and penetration depth of fissure sealants in permanent molars: An in vitro study

Aim: Acid etching alone is insufficient to remove organic residues from enamel, which can compromise the microretention of fissure sealants and lead to microleakage and failure. This study evaluated the impact of four different deproteinization agents on the microleakage and penetration depth of fissure sealants in human molars. Methods: A total of 170 caries-free mandibular third molars were randomly assigned to five groups (n=34 per group): (1) The Control group (acid etching only), (2) The NaOCl group (sodium hypochlorite + acid etching), (3) The Papacarie Duo group, (4) The Brix 3000 group (both papain enzyme + acid etching), and (5) The Bromelain group (10% bromelain + acid etching). Fissure sealants were applied after etching and deproteinization. Microleakage and penetration depth were evaluated after an aging process involving 1000 thermal cycles between 5-55ºC, using a dye penetration method under a stereomicroscope. Results: Within the groups, the Brix 3000 group demonstrated the most favorable microleakage scores, while the Papacarie Duo group exhibited the least favorable scores. Specifically, a microleakage score of 0 was observed in 50%, 32.4%, 23.5%, 20.6%, and 17.6% of the teeth in the Brix 3000, NaOCl, Bromelain, Control, and Papacarie Duo groups, respectively. Furthermore, a penetration depth score of 3 was observed in 29.4%, 29.4%, 26.5%, 11.8%, and 8.8% of the teeth in the Brix, Papacarie Duo, Control, Bromelain, and NaOCl groups, respectively. Conclusions: Deproteinization with Brix 3000 gel prior to acid etching in fissure sealant applications resulted in lower microleakage and greater penetration depth compared to other deproteinization agents and acid-etching alone. Deproteinization agents can be a promising way to yield favorable results Keywords: Bromelains; Dental Enamel; Papain; Pit and Fissure Sealants; Phosphoric Acid

The combined effect of pit and fissure sealant application and oral health education on oral health status of children aged 6–9 years: a 12-month follow-up study in Northeast China

BackgroundChildren aged 6–9 years are vulnerable to dental caries due to age-related limitations and a lack of adequate knowledge regarding oral health and hygiene practices. This study aimed to establish a cohort of children aged between 6 and 9 years and conducted a 12-month follow-up to examine the combined effect of pit and fissure sealant (PFS) application and oral health education on their oral health status.MethodsA cohort study with 12-month follow-up was conducted in Liaoning province, China. A multi-stage stratified cluster sampling approach was employed in the study. The enrolled 6- to 9-year-old children were all from the selected primary schools, who had resided in the designated area for at least 6 months. Children who were unable to cooperate with the examiner or without informed consent from their guardians were excluded. Experienced dental professionals examined the oral health status of primary school children aged 6–9 years. All children and their guardians were mandated to complete a questionnaire (qualitative data) at the beginning of the study. In the experiment group, children underwent PFS application and chairside oral health education. Clinical examinations and questionnaire surveys were repeated at the 12-month follow-up. The chi-square test and binary logistic regression were conducted to investigate the potential risk factors associated with dental caries prevalence (dependent variable). Independent variables were items from the questionnaire (such as living place, parents’ education level and children’ birth weight). The significant variables identified in the chi-square tests were subsequently included in the binary logistic regression analysis.ResultsA total of 4,085 children aged 6–9 years were included in the study, with 1805 participants assigned to the experiment group and 2280 to the control group. At baseline, the caries rates of the experimental and control group were 77.95% and 80.35%, respectively without any statistically significant differences. However, at the 12-month follow-up, the caries rate in the experimental group (83.65%) was significantly lower than that in the control group (86.62%) (P < 0.05). The results from the binary logistic regression analysis indicated that parents with a college degree and children in the experimental group exhibited lower caries rates. Conversely, higher caries rates were associated with the consumption of sweet beverages and foods more than once a day and a lack of knowledge regarding the causes of caries (P < 0.05).ConclusionsIn Liaoning, China, children aged 6 to 9 years exhibited a high prevalence of dental caries. Several factors, including the parent’s education level, the frequency of consuming sweet beverages and foods, and the children’s understanding of the cause of caries, significantly affected the caries prevalence rates. The implementation of PFS application and oral health education effectively reduce the caries rate among the surveyed children.

Adverse Effects of Application of Fluoride Varnish versus Resin-Based Fissure Sealant in Newly Erupted Permanent Molars in Group of Egyptian Children: A Randomized Clinical Trial

Adverse Effects of Application of Fluoride Varnish versus Resin-Based Fissure Sealant in Newly Erupted Permanent Molars in Group of Egyptian Children: A Randomized Clinical Trial

Multiscale insights into mechanical performance of a granite-based geopolymer: Unveiling the micro to macro behavior

Geopolymers (GPs), based on rocks and similar (waste) materials, have shown promising features as alternatives to Ordinary Portland Cement (OPC) in many applications. The properties of these materials can be tailored to a large degree, to meet the requirements of specific applications. This study presents a two-part granite-based GP system developed for wellbore sealant applications in Carbon Capture and Storage (CCS) operations. The system was modified by incorporating different concentrations of a Zn–K-based retarder. The performance of the GP system was then evaluated through consistency analyses, and uniaxial compressive strength (UCS) measurements. Further, the in-situ mechanical attributes of the GP system were assessed through tri-axial experiments at 90 °C and under varying confining pressures. Additionally, the morphology, mineralogy, and chemical composition of the hardened GP system were analyzed using X-ray diffraction (XRD), scanning electronic microscopy with energy dispersive spectroscopy (SEM-EDS), and Fourier transform infrared spectroscopy (FTIR). Consistency analyses revealed that slurries with higher retarder content exhibited improved fluidity but also longer setting times, which could result in fluid invasion and integrity issues. Accordingly, slurries with appropriate setting behavior were identified, striking a balance between rapid strength development and sufficient fluidity for downhole applications. The appropriate flow characteristics of the slurries and the stability of the solidified materials were also verified through rheological assessments, free-fluid tests, and sedimentation analyses. UCS measurements showed a continuous increase in strength for all GP samples, with optimized retarder content yielding the highest late-age mechanical strength. Tri-axial experiments showed that the in-situ Poisson's ratio, compressive strength, and compressive strength to Young's modulus ratio (C/E) of the GP system could be enhanced by 86.79%, 40.26% and 13.05%, respectively, through retarder content optimization. Furthermore, compressive strength and C/E ratios increased with higher confining pressure, while Poisson's ratio remained relatively constant. Moreover, XRD analyses revealed a transition from amorphous to crystalline phases within the GP system, depending on the retarder content, indicating enhanced network connectivity and the formation of new crystalline structures. FTIR analyses supported these observations, demonstrating the formation of new crystals and robust amorphous gels, indicating improved polycondensation and network connectivity in the GP system. Besides, SEM analysis of fractured samples exhibited distinct microstructural characteristics depending on the retarder content, with the optimized retarder content leading to higher crystallinity and more interconnected gel structures. These findings highlight the significance of microscale analysis alongside macroscale assessments when studying GP systems.

SEM study of resin tags depth for filled pit and fissure sealants using subpressure and adhesive system - An experimental analysis

Background: Pit and fissure caries account for about 90% of the caries of permanent posterior teeth and 44% of caries within the first teeth in children and adolescents. Sealant application may be a preventive conservative approach. However, it is still challenging to bolster the retention of the filled sealant and to chop back the microleakage. Aims and Objectives: To evaluate and compare the depth of resin tags of three filled pit and fissure sealants (PFS) using subpressure and adhesive system under scanning electron microscope (SEM). Materials and Methods: This study was in vitro experimental study. Forty-five orthodontically extracted premolars were prepared for resin tag depth measurement and divided according to materials and subgroups. Group A- Resin-based filled PFS, Group B- Resin modified glass ionomer-based filled PFS, Group C- Giomer based filled PFS. Subgroup 1- Only sealant application, Subgroup 2- Subpressure application, Subgroup 3-Adhesive system + Subpressure application. Samples were subjected to thermocycling. The sectioned tooth fragments were polished using a carbide stone and then mounted under SEM for analysis. Photographs of the sections were obtained and the resin tag lengths were measured. Unpaired t-test and one-way analysis of variance test used for analysis. Results were considered significant when P&lt;0.05. Results: The depth of resin tags of the tested materials differed significantly for Giomer-based and resin-modified glass ionomer-based filled PFS group with P&lt;0.05. Whereas Resin-based filled PFS group was not found significant P&gt;0.05 for the depth of resin tags. Conclusion: This study concludes that Giomer based filled PFS group and Resin-modified glass ionomer-based filled PFSs showed the highest Resin tag depth respectively when compared with Resin-based filled PFSs. The Subpressure application group was more effective followed by Adhesive+subpressure application group and Control group.

Micro-Hardness and Surface Roughness of Bulk-Fill Composite Resin: Effect of Surface Sealant Application and Two Bleaching Regimens

Abstract Objectives The aim of this study was to assess the impact of applying a surface sealant and two bleaching regimens, on the micro-hardness, and surface roughness of bulk-fill composite resin Materials and Methods One-hundred twenty specimens were prepared with a diameter of 5 mm and thickness of 4 mm using bulk-fill composite. Specimens were subdivided into group 1: (n= 60), in which Fortify surface sealant was used, and group 2 (control): (n= 60), in which specimens were only finished and polished. After applying in-office and at-home bleaching, micro-hardness and surface roughness were measured before and after bleaching. Statistical analysis was performed using Student's t-test and paired test. Results Hardness values of group 1 were lower than values of group 2 before and after bleaching, with different bleaching procedures. Applying surface sealant and different bleaching regimens led to a significant difference of surface roughness (p &lt; 0.001). Conclusion Applying surface sealant decreases both micro-hardness and surface roughness. The bleaching procedures significantly affect the surface roughness, but not the micro-hardness. Clinical Significance Surface sealant can enhance the surface roughness of bulk-fill composite in nonstress bearing area as it reduces the surface micro-hardness.

296. FIBRIN SEALANT FOR THE PREVENTION OF ANASTOMOTIC LEAKAGE AFTER ESOPHAGECTOMY: INTERIM REPORT OF A PROSPECTIVE, PHASE III, RANDOMIZED CONTROLLED STUDY

Abstract Purpose Anastomotic leakage (AL) is one of the most pernicious complications after esophagectomy for patients with esophageal or esophagogastric junction cancer (EC or EJC). The application of fibrin sealant (FS) may be advantageous for reducing the incidence of AL. This study aims to evaluate the safety and effectiveness of FS in preventing AL in patients undergoing McKeown esophagectomy. Methods In this multicenter, prospective, randomized controlled trial, we planned to recruit 360 patients aged 18–75 years with resectable EC or EJC and the interim analysis was performed when the number of participants reaches 180. Patients assigned to the FS group received McKeown esophagectomy with 2.5 mL Bioseal applied to the cervical anastomosis, while patients in the control group received surgery alone. The primary endpoint was the incidence of cervical AL within the first 3 months postoperatively. Result From February 2019 to November 2021, 180 patients were recruited, with 89 in the FS group and 91 in the control group. There was no statistically difference between the incidence of AL between the two groups [6.7% (6/89) in the FS vs. 14.3% (13/91) in the control group, P = 0.16]. Complications was comparable (P = 0.76) between the FS group (42 of 89, 47.2%) and the control group (45 of 91, 49.5%). No adverse events related to FS or deaths occurred postoperatively. Conclusion The application of Bioseal intraoperatively is feasible and does not increase the risk of complications, and its effectiveness for the prevention of AL needs to be revalidated after the completion of patient enrollment.