Cohesive Failure
Cohesive Failure - Related Videos
01:07
Cohesion
0 Views •
2019
Cohesion is the attraction between molecules of the same type, such as water molecules. Water molecules have an overall neutral charge but are polar molecule. An oxygen atom in one water molecule has a partial negative charge that can bind to a hydrogen atom with a partial positive charge in a second water molecule, forming a hydrogen bond. Each water molecule can form up to four hydrogen bonds with other water molecules. Hydrogen bonds are responsible for water's cohesive nature. On a surface,...
12:49
Measurement of Aggregate Cohesion by Tissue Surface Tensiometry
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Cited by 10 •
2011
We describe a method of measuring binding energy, expressible as tissue surface tension, between cells within 3D tissue-like aggregates. Differences in tissue surface tension have been demonstrated to correlate with invasiveness of lung, muscle, and brain tumors, and are fundamental determinants of establishing spatial relationships between different cell types.
07:35
Gene Transfer for Ischemic Heart Failure in a Preclinical Model
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Cited by 21 •
2011
A method of gene transfer for the treatment of ischemic heart failure is described using a swine model of myocardial infarction. Our simple and reproducible method enables us to readily evaluate the efficacy of various gene transfers with a very simple and reproducible way.
08:40
Standard Test Method ASTM D 7998-19 for the Cohesive Strength Development of Wood Adhesives
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Cited by 6 •
2020
We present a procedure, ASTM D7998-19, for a rapid and more consistent evaluation of both dry and wet strength of adhesive bonds on wood. The method can also be used to provide information on strength development as a function of temperature and time or strength retention up to 250 °C.
10:10
A Novel Murine Model of Arteriovenous Fistula Failure: The Surgical Procedure in Detail
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Cited by 24 •
2016
Here we present a murine model of arteriovenous fistula (AVF) failure in which a clinically relevant anastomotic configuration is incorporated. This model can be used to study the pathophysiology and to test possible therapeutic interventions.
FAQs
Failure begins when the applied stress exceeds the material’s internal strength, concentrating damage within the adhesive, cement, restorative material, or substrate. Cracks then propagate through that material while the bonded surfaces remain relatively intact. This pattern indicates that the limiting factor is the material’s resistance to internal fracture rather than its ability to adhere to the opposing surface.
The distinction identifies where performance is being lost. A cohesive pattern points to weakness within the biomaterial or substrate, whereas separation at the interface suggests inadequate bonding between surfaces. In medical device evaluation, this interpretation prevents researchers from treating a material-composition problem as a surface-preparation problem and helps direct more appropriate changes to design or processing.
Internal strength is the central mechanical factor, because failure occurs when stresses surpass the material’s capacity to remain intact. Material composition and processing can affect that capacity and therefore influence crack development. Assessing these variables helps explain why an adhesive, cement, restorative material, or device component may fracture internally even when its connection to another surface remains comparatively sound.
They determine where the crack traveled relative to the bonded surfaces. A fracture extending through the adhesive, cement, restorative material, or substrate supports a cohesive interpretation, while separation at the joining boundary supports an interfacial interpretation. This location-based assessment connects the observed failure pattern with the material or bonding mechanism most likely responsible for reduced performance.
The concept is relevant wherever a medical material must remain mechanically intact after bonding or integration. Examples include dental restorations, orthopedic implants, prosthetic components, tissue adhesives, and other medical devices. In each setting, identifying an internal fracture helps determine whether durability is limited by the biomaterial itself rather than by the connection between two bonded surfaces.
A cohesive pattern directs attention toward the material’s composition, processing, and mechanical performance. Researchers can use that information to evaluate how the material develops internal strength and resists crack propagation. The resulting changes aim to improve clinical durability, whether the application involves a dental restoration, implant, prosthetic component, tissue adhesive, or another medical device.