Flowable Group Research Articles

Effectiveness of a thrombin-gelatin flowable for treating severe liver bleeding: an experimental study

BackgroundCurrent scientific evidence has pointed out the relevance of hemostatic products for improving clinical outcomes in liver trauma, including increased survival rates and reductions in bleeding-related complications. The purpose of this study was to compare the use of the gelatin-thrombin flowable (Flowable) versus the standard technique of Packing in a new experimental liver injury model.MethodsTwenty-four swine were prospectively randomized to receive either Flowable or standard packing technique. We used a novel severe liver injury model, in which the middle and left suprahepatic veins were selectively injured, causing an exsanguinating hemorrhage. The main outcome measure was the percentage of lost blood volume.ResultsThe median total percentage of total blood volume per animal lost, from injury to minute 120, was significantly lower in the Flowable group (15.2%; interquartile range: 10.7–46.7%) than in the Packing group (64.9%; Interquartile range: 53.4–73.0%) (Hodges-Lehmann median difference: 41.1%; 95% CI: 18.9–58.0%, p = 0.0034). The 24-hour survival rate was significantly higher in the Flowable group (87.0%) than in the Packing group (0.0%) (Hazard ratio (HR) 0.08; 95% confidence interval 0.102 to 0.27; p < 0.0001). Mean-arterial pressure was significantly lower at minute 60 and 120 in the Flowable group than in the packing group (p = 0.0258 and p = 0.0272, respectively). At minute 120, hematocrit was higher in the Flowable than in the packing group (Hodges-Lehmann median difference: 5.5%; 95%CI: 1.0 to11.0, p = 0.0267). Finally, the overall-surgical-procedure was significantly shorter with Flowable than with Packing (Hodges-Lehmann median difference: 39.5 s, 95% CI: 25.0 to 54.0 s, p = 0.0004).ConclusionsThe use of the Flowable was more effective in achieving hemostasis, reducing blood loss, and improving survival rates than standard packing in a severe porcine-liver bleeding model.

Flowable Composite for Orthodontic Bracket Bonding (in vitro study)

Flowable resin composites have been recommended for many clinical uses and have been formulated in a variety of compositions and viscosities to meet various uses. The aim of this study was to determine if flowable composite with or without resins could be used as orthodontic bracket bonding. Sixty noncarious human premolars were divided into three equal groups. Metal brackets were bonded to etched enamel using a composite resin control (Resilience® orthodontic adhesive) and flowable composite with and without sealant resin (Resilience® flowable composite). After 72 hours of incubation in deionized water at 37 C°, debonding was performed with a shearing force. The shear bond strength (SBS) and the mode of bond failure were examined. High significant difference was observed in the SBS between control and flowable groups. Clinically acceptable SBS was found for the two flowable adhesives with bond failures occurred mostly in the bracket–adhesive interface. No significant differences between flowable groups. In conclusion, the use of flowable composite with and without sealant resin is advocated for orthodontic bracket bonding

Comparative Evaluation of Surface Roughness and Colour Stability of Four Different Composite Resins after Application of Desensitising Agents: An In-vitro Study

Introduction: Dentinal Hypersensitivity (DH) is a common clinical condition usually associated with exposed dentinal surfaces. Desensitising agents are regularly used by patients experiencing hypersensitivity, which can affect the physical properties of the existing restorative material. Aim: To evaluate the surface roughness and colour stability of four different types of composite resin restorations after exposure to a desensitising agent. Materials and Methods: The in-vitro study was conducted in the Department of Conservative Dentistry and Endodontics at Ranjeet Deshmukh Dental College and Research Centre, Nagpur, Maharashtra, India from January 2024 to March 2024. Total 56 standardised composite resin discs of size 8×2 mm thickness were prepared using four different types of composites: microhybrid, nanofilled, nanohybrid, and flowable. They were further divided into control and experimental groups based on the application of a desensitising agent, with seven samples in each subgroup. The desensitising agent was applied twice a day for three minutes for one month. Surface roughness was evaluated using a surface profilometer, and colour stability was assessed using a spectrophotometer with the Commision on Ilumination (CIE) L*a*b* formula. The data were analysed using Student’s t-test for pair-wise comparison and One-way Analysis of Variance (ANOVA), with Tukey post-hoc tests for intergroup comparison. Results: The application of a desensitising agent on the samples resulted in a significantly greater effect on the surface roughness of the experimental subgroup than their control counterparts (p≤0.05). Among all groups, the nanofilled group exhibited the lowest surface roughness (0.418±0.047), and the colour change (1.87±0.00) was clinically acceptable. However, the flowable group had the maximum colour change amongst all the other groups (3.16±0.00). Conclusion: Within the limitations of the study, nanofilled composite resin restorative material has minimal surface roughness and colour change after exposure to the desensitising agent. It can be considered the material of choice for restoration in patients with DH.

Comparison of a gelatin thrombin versus a modified absorbable polymer as a unique treatment for severe hepatic hemorrhage in swine

There are many surgical techniques (packing, Pringle maneuver, etc.) and hemostatic agents to manage hepatic bleeding in trauma surgery. This study compares the effectiveness of two different types of hemostatic agents, one is an active flowable hemostat and the other is a passive hemostat made of modified absorbable polymers [MAP]. Both surgical technique and hemostatic agents can be used together as a means of controlling bleeding. We have hypothesized that a single hemostatic agent might be as effective as a unique hemostatic surgical technique. Twenty swine were prospectively randomized to receive either active Flowable (Floseal) or passive MAP powder (PerClot) hemostatic agents. We used a novel severe liver injury model that caused exsanguinating hemorrhage. The main outcome measure was total blood loss volume. The total volume of blood loss, from hepatic injury to minute 120, was significantly lower in the Flowable group (407.5 cm3; IqR: 195.0–805.0 cm3) compared to MAP group (1107.5 cm3; IqR: 822.5 to 1544.5 cm3) (Hodges–Lehmann median difference: − 645.0 cm3; 95% CI: − 1144.0 to − 280.0 cm3; p = 0.0087). The rate of blood loss was significantly lower in the flowable group compared with the MAP group as measured from time of injury to minutes 3, 9, 12, and 120 (except for 6 min). The mean arterial pressure gradually recovered in the flowable group by 24 h, whereas in the MAP group, the mean arterial pressure was consistently stayed below baseline values. Kaplan–Meier survival analysis indicated similar rates of death between study groups (Logrank test p = 0.3395). Both the flowable and the MAP hemostatic agents were able to effectively control surgical bleeding in a novel severe liver injury model, however, the flowable gelatin–thrombin agent provided quicker and better bleed control.

Evaluating the effect of preheating on resin composites in pit-and-fissure caries treatments with a digital intraoral scanner.

To evaluate the effect of preheating on the microleakage and surface hardness of resin composites in the treatment of pit-and-fissure caries with various widths,as measured by an intraoral scanner. A total of 153L-shaped cavities with different widths (1mm, 1.6mm and 2mm) were prepared on the buccal or palatal/lingual surfaces of human molars. The cavities were measured in three dimensions by a TRIOS scanner and then filled with various resins (room temperature Z350 flowable resin and room temperature and 60℃ Z350 universal resin). Microleakage and gap formation at 2 sites were evaluated by stereomicroscopy and scanning electron microscope. Resin samples were prepared, and the top surface Vickers hardness (VHNtop) of all samples was measured at 1day and 30 days postirradiation. No difference were observed in the 3D scans for the cavities sizes among groups with the same width. For the 1mm-wide cavity, the lowest microleakage was obtained with the flowable group; for the 1.6mm-wide cavity, the nonpreheating universal group showed the highest microleakage at site 1, and the preheating group exhibited lower microleakage than that of the nonpreheating universal group at site 2; and for the 2mm-wide cavity, the preheating group presented lower microleakage at site 2. The gap formations were consistent with the microleakage degrees. The preheating group exhibited the highest VHNtop at 1day and 30 days postirradiation. A digital intraoral scanner could be used to scan the cavities in three dimensions. Preheating technology could reduce the microleakage of Z350 universal resin and enhance its surface hardness.

Marginal Adaptation of Flowable vs Sonically Activated or Preheated Resin Composites in Cervical Lesions.

To investigate marginal integrity of restorations applied with preheated and non-preheated composite, flowable composite, sonically activated composite, and a new thermo-viscous bulk-fill composite using near-infrared technology for preheating, in class V cavities of human molars. Standardized cavities were prepared on the buccal surfaces of 60 human mandibular molars and restored with one of the following resin composite materials after application of an etch-and-rinse adhesive (OptiBond FL, Kerr): non-preheated or preheated conventional composite (Filtek Supreme XTE, 3M Oral Care), preheated thermo-viscous composite (VisCalor bulk, Voco), soncially activated composite (SonicFill 3, Kerr), or flowable composite (Filtek Supreme XTE Flowable, 3M Oral Care) applied in bulk or as a lining material using the snow-plow technique. After light curing and polishing, the percentage of continuous margins (PCM) of the restorations in enamel and dentin was assessed using SEM both before and after thermomechanical loading (TML). TML was carried out with 3000 thermal cycles (5°C-50°C) and a simultaneous mechanical stress application with 1.2 million load-cycles (1.7 Hz, 49 N) in a computer-controlled masticator. Non-parametric statistical analysis was performed using Wilcoxon, Kruskal-Wallis, and Mann-Whitney U-tests (α = 0.05). All groups revealed a significant decline in marginal integrity after TML in both enamel and dentin. Although the flowable group in enamel and the snow-plow group in dentin showed the highest PCM before TML, the differences between the groups were compensated after TML. All of the tested composites and application methods showed similar marginal integrities after thermomechanical loading and can be recommended for clinical implementation.

Comparison of adhesion forces developed by foil mesh of various dimensions applied in combination with composites of different viscosity

The aim of this study was to determine what effect various combinations of particular bracket bases and composites of different viscosity have on adhesion force. Eighty extracted premolars, upper and lower, were randomly assigned to four groups of 20 teeth and the combinations of either flowable or paste composite and brackets with either 80-gauge or 100-gauge foil mesh were applied to their labial surfaces accordingly: group A: flowable composite+80-mesh base; group B: flowable composite+100-mesh base; group C: paste composite+80-gauge base; group D: paste composite+100-gauge base. Each sample was subjected to shear bond stress to failure using a Zwick Roell Z050 testing machine at 50N/min load. The load required to detach each bracket was recorded in N and subsequently converted to MPa. After debonding, each tooth was analysed under optical microscope at 12× magnification and photographed prior to calculation of the Adhesive Remnant Index (ARI). The paste composite showed greater adhesion strength than the flowable in all cases, but this was further increased when the 80-gauge, rather than the 100-gauge, mesh was used. No statistically significant difference in ARI values was found between the flowable groups (groups A and B), on the other hand, in the paste composite groups, a statistically significant difference was highlighted between the 80-gauge (group D) and 100-gauge (group C) mesh bracket bases. Both the density of the composite and the gauge of a mesh bracket base are able to influence bond strength and the bond failure interface.