"In A/J strain,
we found significant decreases in stiffness
with increasing fluoride dose treatment.
There was a significant difference between the treatment group
0 ppm and 100 ppm... In the A/J strain, there was
a decrease in ultimate load with increasing fluoride dose treatment,
with significant differences between the treatment group 0 ppm
and the treatment group 100 ppm (p=0.017)."
SOURCE: Mousny M, et al. (2006). The genetic influence on bone
susceptibility to fluoride. Bone
Aug 18; [Epub ahead of print]
"In group treated with NaF both the strength
and stiffness were significantly decreased
when compared with those in ovariectomized control."
SOURCE: Czerny B, et al. (2004). The Effect
of Tamoxifen and Fluoride on Bone Mineral Density, Biomechanical
Properties and Blood Lipids in Ovariectomized Rats. Basic
& Clinical Pharmacology & Toxicology
92:162–165.
"The highest fluoride intake (50 mg/L)
significantly diminished vertebral strength...
This impairment of mineralization by fluoride appeared to be the
primary cause of the diminished vertebral strength."
SOURCE: Turner CH, et al. (2001). Combined effects of diets with
reduced calcium and phosphate and increased fluoride intake on
vertebral bone strength and histology in rats. Calcified Tissue
International 69: 51-57.
"Bending strength
of the femoral shaft decreased significantly after fluoride therapy.
We conclude that high fluoride intake
decreases bone quality of the femoral shaft and neck in young
growing rats."
SOURCE: Bohatyrewicz A. (1999). Effects of fluoride on mechanical
properties of femoral bone in growing rats. Fluoride 32:
47-54.
"In this study, despite the observed
increased in hardness of both cancellous and cortical bone, the
fracture stress and elastic modulus of vertebrae tested in compression
and femora tested in three-point bending were decreased by
fluoride treatment."
SOURCE: Chachra D, et al. (1999). The effect of fluoride treatment
on bone mineral in rabbits. Calcified Tissue International
64:345-351.
"It is likely that the bone changes induced
by fluoride will lead to an impaired biomechanical competence
of antlers from deer inhabitating regions
with higher levels of environmental fluoride. We,
therefore, would expect to find an increased incidence of antler
breakage in such populations."
SOURCE: Kierdorf U, et al. (1997). Fluoride content and mineralization
of red deer (Cervus elaphus) antlers and pedicles from fluoride
polluted and uncontaminated regions. Archives of Environmental
Contamination and Toxicology 32: 222-227.
"Fluoride treatment reduced all biomechanical
measurements. The reductions
ranged from 5% to 25%. Several of these reductions were statistically
significant: the fracture force of the femoral neck was reduced
by 25%, the fracture stress of the L-5 vertebra was reduced by
19%, and the bending modulus of the femur was reduced by 21%."
SOURCE: Turner CH, et al. (1997). Fluoride treatment increased
serum IGF-1, bone turnover, and bone mass, but not bone strength,
in rabbits. Calcified Tissue International 61:77-83.
"Fluoride concentrations of 15 and 50
ppm reduced femoral bone strength in renal-deficient animals.
Femoral bone strength also was reduced in control animals given
50 ppm fluoride."
SOURCE: Turner CH, et al. (1996). High fluoride intakes cause
osteomalacia and diminished bone strength in rats with renal deficiency.
Bone 19:595-601.
"NaF reduced the strength of cancellous
bone from the L4 vertebrae, relative to the control animals,
and the stiffness (resistance to deformation) of the femora."
Bone strength "did not increase
with bone volume, suggesting that for bones with higher volume,
there was less strength per unit volume, that is, a
deterioration in bone 'quality.'"
SOURCE: Lafage MH, et al. (1995). Comparison of alendronate and
sodium fluoride effects on cancellous and cortical bone in minipigs.
A one-year study. Journal of Clinical Investigations 95(5):2127-33.
"Load corrected for ash content, which
is a measure of bone quality, decreased significantly after fluoride
therapy. It is concluded that the increase in bone mass during
fluoride treatment does not translate into an improved bone strength
and that the bone quality declines.
This investigation thereby supports the hypothesis of a possible
negative effect of fluoride on bone quality."
SOURCE: Sogaard CH, et al. (1995). Effects of fluoride on rat
vertebral body biomechanical competence and bone mass. Bone
16(1): 163-9.
"To date, animal studies of fluoride effects on bone have
used young and healthy experimental animals exclusively. The effects
of fluoride on old animals, that more closely represent people
most likely to fracture, have not been studied.... In
older rats receiving 50 ppm fluoride, failure stress was decreased
by as much as 29%. Such
dramatic losses in bone strength only have been shown previously
in studies where fluoride intake was accompanied by calcium deficiency,
yet, in this study, calcium intake in the older rats was no different
from that in the younger rats... [I]t
is possible that aging effects and fluoride incorporation in
the bone act synergistically to decrease bone strength."
SOURCE: Turner CH, et al. (1995). Fluoride reduces bone strength
in older rats. Journal of Dental Research 74:1475-81.
"[S]everal investigators - including ourselves
- have shown that bone strength decreases as bone fluoride
levels in the mineral phase increase to beyond about 4500
ppm."
SOURCE: Turner CH, Dunipace AJ. (1993). On fluoride and
bone strength (letter). Calcified Tissue International
53: 289-290.
"Interfacial bonding interactions
between the mineral and organic constituents of bone play an important
role in the mechanical properties of cortical bone... Under
a uniaxial tensile force, modification
of interfacial bonding by phosphate and fluoride ions results
in a reduction in the ultimate and yield stress and elastic
modulus. In tension, phosphate
ions effect is reversible upon removal of phosphate ions, while
the fluoride ion effect is irreversible. Interestingly, when tested
in compression, phosphate ion treatment results in a stiffening
effect, while fluoride ions continue
to lower the ultimate stress and elastic modulus."
SOURCE: Walsh WR, Guzelsu N. (1993). The role of ions and mineral-organic
interfacial bonding on the compressive properties of cortical
bone. Bio-medical materials and engineering 3: 75-8
"The results demonstrate that water fluoride
levels of 1 ppm may lead to increased bone strength, while water
fluoride levels of 4 ppm would be expected to cause a decrease
in bone strength."
SOURCE: Turner CH, et al. (1992). The
effects of fluoridated water on bone strength. Journal of Orthopedic
Research 10:581-7. (NOTE: In
subsequent studies, Turner was unable to duplicate the beneficial
effects on bone strength which he found at low doses in this study.
As Turner noted in a more extensive, follow-up study: "the
present results showed no evidence of increased bone strength
resulting from fluoride levels below 16 ppm." - Ref:: J Dent
Res; 1995; Vol 74: 1475-81.)
"Bone quality seemed to be affected since
significant decreases in bone-breaking strength and significant
increases in bone mineralization
were observed in fluoride-treated kestrels. When the breaking
strength (LOAD) was expressed as the maximum load the bone can
carry, no significant differences were detected among groups.
However, when these figures are used to calculate the maximum
stress the bone can resist, bone quality clearly
decreased as more fluoride was added to the diet of the growing
kestrels."
SOURCE: Bird DM, Carriere D, Lacombe D.
(1992). The effect of dietary sodium fluoride on internal organs,
breast muscle, and bones in captive American kestrels (Falco sparverius).
Archives of Environmental Contamination
and Toxicology 22:242-6.
"The reduction in interfacial bonding
due to fluoride action lowers the mechanical properties of
bone tissue."
SOURCE: Walsh WR, Guzelsu N. (1991). Fluoride ion effect on interfacial
bonding and mechanical properties of bone. Journal of Biomechanics
24: 237.
"[T]he mechanical parameters for the
fluorotic animals were unchanged...or decreased...It
is concluded that the increased bone mass during the initial stages
of fluoride treatment does not necessarily indicate an improved
bone quality."
SOURCE: Mosekilde L, et al. (1987). Compressive strength, ash
weight, and volume of vertebral trabecular bone in experimental
fluorosis in pigs. Calcified Tissue Research 40: 318-322.
"The data reported herein suggested that
levels of dietary F greater than 7 ppm are detrimental to bone
integrity. Breaking stress and modulus of elasticity were
reduced significantly at each level of added dietary F in both
experiments. Similar observations have been made with nearly all
species that have been subjected to F ingestion."
SOURCE: Burnell TW, et al. (1986). Effect of dietary fluorine
on growth, blood and bone characteristics of growing-finishing
pigs. Journal of Animal Science 63(6):2053-67.
"Thirty-six young rats were used to determine the effect
of the fluoride on collagen synthesis in healing of fracture...
Collagen synthesis of the callus was examined histochemically
and histologically. In the fluoride-treated
group, collagen synthesis was found to be defective, while
it was normal in the controls."
SOURCE: Uslu B. (1983). Effect of fluoride on collagen synthesis
in the rat. Research and Experimental Medicine 182:7-12.
"In the present study high levels of fluoride
in the drinking water did not prevent osteoporosis, but in some
experiments, by certain criteria, tended to increase it."
SOURCE: Robin JC, et al. (1980). Studies on osteoporosis III.
Effect of estrogens and fluoride. Journal of Medicine 11(1):1-14.
"F at high levels, tended to decrease
bone ash, cortical thickness, and mechanical strength parameters."
SOURCE: Guggenheim K, et al. (1976). The effect of fluoride on
bone of rats fed diets deficient in calcium or phosphorus. Calcified
Tissue Research 22: 9-17.
"The strength of osteopenic bone from
calcium deprived rats, quail and roosters was significantly reduced
after fluoride supplementation...This detrimental effect on
bone strength must be considered in any therapeutic attempt
to use fluoride ion to stimulate bone formation in osteopenic
bone disorders."
SOURCE: Riggins RS, et al. (1976). The effect of fluoride supplementation
on the strength of osteopenic bone. Clinical Orthopedics
(114):352-7.
"The administration of sodium fluoride increased bone diameter,
indicating stimulation of periosteal bone formation, but bone
strength was reduced or not affected by fluoride ingestion."
SOURCE: Riggins RS, et al. (1974).
The Effects of Sodium Fluoride on Bone Breaking Strength. Calcified
Tissue Research 14: 283-289.
"Our observations corroborate the findings that, in general,
elevated dietary fluoride results in an acceleration of bone mineralization.
Uniquely, however, the increase
in mineralization was accompanied by a decrease in bone strength...
the changes in bone that occur with prolonged and excessive fluoride
ingestion may result in a reduction of bone strength."
SOURCE: Chan MM, et al. (1973). Effect of Fluoride on Bone Formation
and Strength in Japanese Quail. Journal of Nutrition 103:
1431-1440.
"Femurs of fluoride-treated rats exhibited
a decrease in mechanical strength as manifested by a decrease
in ultimate stress to breaking as well as decrease in limit and
modulus of elasticity."
SOURCE: Wolinsky I, et al. (1972). Effects of fluoride on metabolism
and mechanical properties of rat bone. American Journal of
Physiology 223: 46-50.
"In the low calcium group a similar significant
increase in flexibility appeared at the 10.0 ppm dosage level
as well as the 45.0 ppm, but a significant decrease in strength
at the two dosage levels were observed. These were in direct relation
to the amount of fluoride given."
SOURCE: Beary DF. (1969). The effects of fluoride and low calcium
on the physical properties of the rat femur. Anatatomical Record
164: 305-316.
"[T]he heavily fluorinated bone tended
to break under less stress than did bone from any other group.
These findings suggest that the heavily fluorinated bone was not
as strong as the bone from normal rats or from rats fed low-calcium
diets without fluoride."
SOURCE: Daley R, et al. (1967). The Effects of Sodium Fluoride
on Osteoporotic Rats. The Journal of Bone and Joint Surgery
(Abstract). 49A:796.
"[T]he decrease in the mean breaking strength
was significant statistically" among the fluoride-treated
rats, and "is in agreement with the known fact that the
breaking strength of bone decreases with increased fluoride intake."
SOURCE: Gedalia I, et al. (1964). Effects of Estrogen
on Bone Composition in Rats at Low and High Fluoride Intake. Endocrinology
75: 201-205.
"Cristiani working with guinea pigs found that the fragility
of the bones was increased about 20 per cent in the fluorized
animals."
SOURCE: Dean HT. (1936). Chronic endemic
dental fluorosis. Journal of the American Medical Association
107: 1269-1273.
"The bones are subject to easy fracture."
SOURCE: Blood DC, Henderson JA, Radostits OM, eds. (1979). Veterinary
Medicine: A Textbook of the Diseases of Cattle, Sheep, Pgs and
Horses. 5th Edition. Lea & Febiger, Philadelphia.
"The bone was brittle and shattered
easily when cut on a bandsaw."
SOURCE: Krook L, Maylin GA. (1979). Industrial fluoride pollution.
Chronic fluoride poisoning in Cornwall Island cattle. Cornell
Veterinarian 69(Suppl 8): 1-70.
"fluorotic specimens had a lower tensile
strength and strain but a higher compressive strength and
strain than the nonfluorotic ones."
SOURCE: Gaynor F, et al. (1976). Mechanical properties and density
of bone in a case of severe endemic fluorosis. Acta Orthopaedica
Scandinavica 47: 489-495.
"Lameness, pain, exostoses, emaciation, and bone
fractures were symptoms associated
with horses exposed to F ingestion."
SOURCE: Lillie RJ. (1970). Air Pollutants Affecting the Performance
of Domestic Animals: A Literature Review. U.S. Dept. of Agriculture.
Agricultural Handbook No. 380. Washington D.C.
"The first sign of fluorosis in cattle
(and probably also in deer) is mottling, pitting, and black discoloration
of the teeth. Affected teeth are soft and show abnormal wear.
Later the leg and foot bones may become
deformed or fractured, resulting
in lameness."
SOURCE: Karstad L. (1967). Fluorosis
in deer (Odoceileus virginianus). Bulletin of the Wildlife
Disease Association 3:42-46.
"In advanced skeletal fluorosis the bones
are brittle."
SOURCE: Adams PH, Jowsey J. (1965). Sodium fluoride in the treatment
of osteoporosis and other bone diseases. Annals of Internal
Medicine 63: 1151-1155.
"In the macerated cattle specimens the
bone was brittle and crumbled readily. The new bone was
as fragile as chalk..."
SOURCE: Johnson LC. (1965). Histogenesis and mechanisms in the
development of osteofluorosis. In: H.C.Hodge and F.A.Smith, eds
: Fluorine chemistry, Vol. 4. New York, N.Y., Academic press (1965)
424-441.
"One of the most prominent features of fluorosis in cattle
in England, however, was the frequency of actue severe lameness,
especially in the early summer. It resembled that described by
Towers (1954) who associated it with fracture of the pedal bone
(3rd phalanx)....This suggests that traumatic
factors played a part in producing the lameness by causing damage
to bones which were relatively fragile as a result of skeletal
accumulation of fluorine..."
SOURCE: Burns KN, Allcroft R. (1964). Fluorosis in Cattle. 1 -
Occurrence and Effects in Industrial Areas of England and Wales
1954-57. Ministry of Agriculture, Fisheries and Food. Animal Disease
Surveys Report No 2, Part I. Her Majesty's Stationery Office,
London.
"Increased fragility of the bones
may be present, and they can be friable and crumbly."
SOURCE: Kumar SP, Harper RA. (1963). Fluorosis in Aden. British
Journal of Radiology 36: 497-502.
"During the examination of the Achintee
sheep, an unusally large number of fractures were detected;
these involved ribs, mandible, and pelvis."
SOURCE: Agate JN, et al. (1949). Industrial fluorosis: A study
of the hazard to man and animals near Fort William, Scotland.
Medical Research Council Memorandum No. 22. His Majesty's Stationery
Office, London.
"High fluorine levels interfere with mineral
metabolism and cause abnormal growth of bone that may be structurally
weak."
SOURCE: Huffman WT. (1949). Effects on livestock of air contamination
caused by fluoride fumes. In: Air Pollution. Proceedings of the
United States Technical Conference on Air Pollution. McGraw-Hill
Book Co, New York. pp. 59-63.
"The bone is abnormally brittle."
SOURCE: Lyth O. (1946). Endemic fluorosis in Kweichow, China.
The Lancet 1: 233-235
"The osteomalacic condition (of fluorosis) to some extent
varies with the species and age of the animal. Certain features
are common, however... Common features are the
reduced strength of the bones, the tendency to form exostoses,
bone atrophy, and a deficient calcification."
Roholm K. (1937). Fluoride intoxication: a clinical-hygienic study
with a review of the literature and some experimental investigations.
H.K. Lewis Ltd, London.
Summation
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