Abstract
The mechanical properties of composite material (such as bone) rely on the properties of its constituents as well as the interfacial bonding between them. Bone tissue is a porous mineralized matrix composite of inorganic bone mineral and organic constituents (collagen and non-collagenous proteins). The porosity of bone is due in part to the organic lined vascular channels (Haversian canals) which separates bone fluid spaces. Detergent treatments can be used to remove some of the organic layers and allows ions access to the mineralized matrix and the mineral-organic interface to examine the role of interfacial bonding on the mechanical properties of bone. This study demonstrates the importance of interfacial bonding between the mineral and organic constituents of bone through fluoride ion treatments. Fluoride ions alter interfacial bonding between the mineral and organic components of bone by exchanging with OH ions of bone mineral and creating an unfavourable electrostatic condition by a rise in pH. The reduction in interfacial bonding due to fluoride action lowers the mechanical properties of bone tissue.
-
-
The effect of in vitro fluoride ion treatment on the ultrasonic properties of cortical bone
The mechanical properties of composites are influenced, in part, by the volume fraction, orientation, constituent mechanical properties, and interfacial bonding. Cortical bone tissue represents a short-fibered biological composite where the hydroxyapatite phase is embedded in an organic matrix composed of type I collagen and other noncollagenous proteins. Destructive mechanical testing
-
Varying the mechanical properties of bone tissue by changing the amount of its structurally effective bone mineral content
The effect of fluoride ions on the mechanical properties of bone tissue in tension was investigated with an in vitro model. Structurally effective Bone Mineral Content (BMC) of bovine bone tissue was changed by fluoride ion treatment. First, bovine cortical bone specimens were treated with a detergent solution in order
-
The role of ions and mineral-organic interfacial bonding on the compressive properties of cortical bone
Bone tissue is a composite material composed of an inorganic stiff mineral phase embedded in a compliant organic matrix. Similar to other composites, the mechanical properties of bone depend upon the properties, volume fraction, and orientation of its constituents as well as the bonding interactions. Interfacial bonding between the mineral
-
In situ observation of fluoride-ion-induced hydroxyapatite-collagen detachment on bone fracture surfaces by atomic force microscopy
The topography of freshly fractured bovine and human bone surfaces was determined by the use of atomic force microscopy (AFM). Fracture surfaces from both kinds of samples exhibited complex landscapes formed by hydroxyapatite mineral platelets with lateral dimensions ranging from ~90 nm × 60 nm to ~20 nm × 20 nm. Novel AFM techniques
-
The effect of fluoride treatment on bone mineral in rabbits
Fluoride therapy has been used clinically for many years, but its use remains controversial and many basic questions remain unanswered. Accordingly, this study returns to an animal model to study the effects of high doses of fluoride on bone mineral in rabbits. Twelve rabbits, aged 3(1/2) months at the start
Related Studies :
-
-
-
Skeletal Fluorosis Causes Bones to be Brittle & Prone to Fracture
It has been known since as the early as the 1930s that patients with skeletal fluorosis have bone that is more brittle and prone to fracture. More recently, however, researchers have found that fluoride can reduce bone strength before the onset of skeletal fluorosis. Included below are some of the
-
Fluoride Reduces Bone Strength Prior to Onset of Skeletal Fluorosis
The majority of animal studies investigating fluoride's impact on bone strength have found that fluoride has either no effect, or a detrimental effect, on bone strength. Importantly, several of the animal studies that have found fluoride reductes bone strength have reported that this reduction in strength occurs before signs of skeletal fluorosis
-
Mechanisms by which fluoride may reduce bone strength
Based on a large body of animal and human research, it is now known that fluoride ingestion can reduce bone strength and increase the rate of fracture. There are several plausible mechanisms by which fluoride can reduce bone strength. As discussed below, these mechanisms include: Reduction in Cortical Bone Density De-bonding of
-
"Pre-Skeletal" Fluorosis
As demonstrated by the studies below, skeletal fluorosis may produce adverse symptoms, including arthritic pains, clinical osteoarthritis, gastrointestinal disturbances, and bone fragility, before the classic bone change of fluorosis (i.e., osteosclerosis in the spine and pelvis) is detectable by x-ray. Relying on x-rays, therefore, to diagnosis skeletal fluorosis will invariably fail to protect those individuals who are suffering from the pre-skeletal phase of the disease. Moreover, some individuals with clinical skeletal fluorosis will not develop an increase in bone density, let alone osteosclerosis, of the spine. Thus, relying on unusual increases in spinal bone density will under-detect the rate of skeletal fluoride poisoning in a population.
-
The Relationship Between Fluoride, Bone Density, and Bone Strength
Although fluoride has generally been found to reduce the bone density of cortical bone, it is well documented that fluoride can increase the density of trabecular bone (aka cancellous bone). Trabecular bone is the primary bone of the spine, whereas cortical bone is the primary bone of the legs and arms. While increases in
Related FAN Content :
-