Urinary Fluoride Levels Research Articles

Operational state of drinking water defluorination project and situation of fluorosis in children aged 8 to 12 in Dagang district of Tianjin in 2009

Objective To investigate the state of drinking water defluorination project in Dagang district and study urinary fluoride levels and detect dental fluorosis of children aged 8 to 12, and to provide scientific basis for prevention and control of fluorosis. Methods Five defluorination projects in rural streets (towns) with highfluoride water and 2 urban water supply projects were choosen to investigate the running status in Dagang district Tianjin in 2009. Five rural and 2 urban schools were choosen to select 100 children aged 8 to 12 (for gender, age matched) in each primary school to study urinary fluoride levels and detection of dental fluorosis. Results A total of 66 defluorination projects in 73 villages were surveyed, among which 61 projects actually worked normally with using rate 92.4%(61/66). Water qualification of all projects could not be ensured due to direct project managers'lack of necessary expertise. In 2009, water qualification rate were 39.3%(24/61 )among the project normally used,with highlighted problem of biological pollution. A total of 490 children aged 8 - 12 in 5 rural towns were surveyed,dental fluorosis rate were 90%(441/490), and dental fluorosis index were 1.82. A total of 207 children aged 8 - 12in 2 urban areas were surveyed, the detection rate of dental fluorosis was 49.8%(103/207), and dental fluorosis index were 0.86. The urinary fluoride level of 230 children aged 8 - 12 in the 5 villages were surveyed. The Range of geometric mean of urinary fluoride were 1.82 - 2.70 mg/L. The urinary fluoride of 102 children aged 8 - 12 in the 2 urban area were surveyed. The Range of geometric mean of urinary fluoride were 1.53 - 1.72 mg/L. Conclusions There was phenomenon of high coverage, low utilization rate and less water consumption in the villages of Dagang district, Tianjin drinking water defluoridation projects, thus the health effects of the projects was minimum.Significant health effects is found in the defluorination projects in the urban areas with high coverage and high utilization rate. Studying new water improvment methods and new forms of water supply system is urgent for solving the problems met in the ineffective water defluorination project. Key words: Drinking water; Fluorosis, dental; Engineering; Data collection

Association of Fluoride Exposure and Bone Mineral Density: A Comparison of Area With Individual

PP-29-080 Background/Aims: Although the benefit of fluoridation in the prevention of dental caries has been overwhelmingly substantiated, the effect of fluoride on bone mineral density (BMD) is less clear. This cross-sectional study was designed to compare BMD of adults exposed to fluoride from various source in environment by individual level. Methods: Participants recruited from 2 Korean cities, Siwha with naturally occurring fluoride in its water system and Ansan with fluoridated water system since 2001. They participated voluntarily with a written informed consent. All subjects took part in BMD examination. BMD was measured by means of dual-energy x-ray absorptiometry at left heel of the subject. To obtain individual fluoride exposure, serum (n = 565), 24 hours urine (n = 99), fingernail (n = 70), and toenail (n = 70) were collected. The measurement of fluoride concentration in serum, 24 hours urine, fingernail, and toenail were made by fluoride ion electrode (Orion Research EA940). Linear regression analysis was performed. Outcome variable was BMD, and explanatory variables were fluoride concentration in serum, 24 hours urine, fingernail, and toenail. Confounders were age, gender, residential area, and monthly household income. Results: BMD showed no relationship with fluoride level in serum, 24-hour urine, fingernail, and toenail. BMD has a tendency of decreasing as the toenail fluoride level increased (P = 0.082). Conclusion: Based on the results of this study, exposure to fluoride appears to have no impact on bone mineral density. However, the relationship of fluoride exposure with bone mineral density by individual and area level requires further investigation.

Fluorotic cervical compressive myelopathy, 20 years after laminectomy: A rare event

Background:Spinal cord compression in flourosis is a common complication. These complications are mainly due to compression of the spinal cord by thickening and ossification of posterior longitudinal ligament and ligamentum flavum. Surgical decompression is the treatment of choice for fluorotic spinal cord compression. The recurrence of spinal cord compression after surgical decompression in flourosis is a rare event.Case Description:We are presenting a case of a 63-year-old man who belonged to Kanpur, an endemic fluorosis region in India, with symptoms of cervical cord compression cranial to the operative site, 20 years after laminectomy for cervical fluorotic myelopathy. Urinary and serum fluoride levels were elevated. The patient underwent a skeletal survey: computed tomography and magnetic resonance imaging of the cervical spine showed a postoperative defect of laminectomy, osteosclerosis, osteophyte formation, calcification of the intraosseus membrane in the forearm, thickening and ossification of the posterior longitudinal ligament at C1, thickening and ossification of the residual ligamentum flavum at C1/C2, and dural calcification at the C2 vertebral level and compressive myelopathy. The patient refused surgical decompression and was managed with tizanidine HCl (an antispasticity medicine), a sublingual single night dose, 8 mg for symptomatic relief.Conclusion:The recurrence of spinal cord compression in the fluorotic spine 20 years after laminectomy is a very unusual event and hence the patient should be kept under observation for a long duration. This case report contributes to the literature associated with the management of fluorotic spine.

Serum Copper, Zinc, and Magnesium Levels in Patients with Chronic Fluorosis

Although there are many studies on effect of fluoride on trace elements in experimental animals, few studies exist on serum trace elements levels in patients with endemic fluorosis. We aimed to determine the serum levels of trace elements including serum copper (Cu), zinc (Zn), and serum levels of minerals including calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K) in patients with endemic fluorosis. The study group consisted of 30 patients with endemic fluorosis (17 females, 13 males, mean age 33.53±9.85 years). An age, gender, and body mass index matched 30 healthy volunteers comprised control group (21 females, ten males with a mean age 33.93±7.39 years). Urine fluoride levels of chronic fluorosis patients were significantly higher than that of control subjects as expected (1.92±0.10 mg/l vs. 0.41±0.09 mg/l, respectively; P<0.001). Serum Cu levels (89.14±16.77 μg/dL vs. 102.69±25.04 μg/dL, respectively, P=0.017), serum Zn levels (77.98±20.58 μg/dL vs. 94.57±35.87μg/dL, respectively, P=0.032), and serum Mg levels (1.92±0.18 mg/dL vs. 2.07±0.31 mg/dL, respectively, p=0.022) was significantly lower in chronic fluorosis patients than in controls. There were no statistically significant differences between the fluorosis group and control group with respect to serum levels of Na, K, Ca, and P. We concluded that chronic fluorosis is associated with reduced serum levels of Cu, Zn, and Mg.

Skeletal fluorosis due to excessive tea and toothpaste consumption

We describe the case of a 53-year-old woman who presented with a metatarsal fracture and was found to have a bone mineral density (BMD) T-score of +11 in the lumbar spine and +7.6 in the hip. Subsequent investigation revealed very high serum, urine and tissue fluoride levels, associated with excessive tea and toothpaste consumption. The case emphasises the need to exclude fluorosis in individuals with unexpectedly high BMD levels.

Serum Parathyroid Hormone Levels in Chronic Endemic Fluorosis

Endemic waterborne fluorosis is a public health problem in Isparta, a city located in southern Turkey. Fluoride is a cumulative element that increases metabolic turnover of the bone and also affects the homeostasis of bone mineral metabolism. There are number of similarities between the effects of excess parathyroid hormone (PTH) and fluorosis on bone. So fluoride might show its effect via PTH. We aimed to determine PTH levels in patients with endemic fluorosis to estimate the possible toxic effects of chronic fluoride intake. Fifty-six patients with endemic fluorosis and 28 age-, sex-, and body-mass-index-matched healthy controls were included in this study. Endemic fluorosis was diagnosed according to the clinical diagnosis criteria of Wang. The urine fluoride levels of fluorosis patients were significantly higher than those of control subjects as expected (1.9 ± 0.1 vs. 0.4 ± 0.1 mg/L, respectively; P < 0.001). PTH levels in fluorosis group were significantly higher than control group (65.09 ± 32.91 versus 47.40 ± 20.37, respectively; P = 0.01). The results of our study demonstrate that serum PTH levels are increased in patients with endemic fluorosis. Fluoride, by interfering calcium balance, may be the cause of secondary hyperparathyroidism.

Child-education program for the reduction of health risks due to fluoride in water sources in the Chiang Mai Basin, Thailand

Groundwater is the major source of drinking water in Lamphun Province in the Chiang Mai Basin, Thailand. However, groundwater contains high fluoride up to 16 mg F/L, which has caused dental and skeletal fluorosis. Although Thai Government installed RO membrane plants for the removal of fluoride from groundwater; and delivers RO-filtered bottled water that contains less fluoride than the Thai Standard of 0.7 mg F/L, it was found that the urinary fluoride levels are still high among the residents. To find the major sources of fluoride intake, fluoride contents in various water sources, such as village water supply, shallow and deep groundwaters, rain water and bottled water, were measured, and the local people's behavior on water uses was recorded by interview and questionnaire study. As a result, it was found that the highest risk of fluoride ingestion comes from cooking rice with fluoride-containing water because of a lack of knowledge on fluoride sources and fluoride chemistry. To reduce the health risks arising from fluoride intake, a hands-on educational program on the sources and risks of fluoride in water was developed and implemented in the local schools. The participatory educational program promoted active involvement of schoolchildren, but it was found that the effectiveness of education varied depending on the questions we asked. Therefore, it needs to be improved by an iterative and interactive educational program. In conclusion, it was found that the benefits of providing safe drinking water using such advanced technology as RO membrane can be maximized only when it comes along with a participatory educational program on fluoride sources and health risks.

Impact of chronic fluorosis on left ventricular diastolic and global functions

Sixty three patients with endemic fluorosis (36 males/27 females; mean age 33.9 ± 8.6 years) and 45 age, sex and body mass index (BMI) matched healthy controls (30 males/15 females; mean age 32.7 ± 8.8 years) were included in this study. Basic echocardiographic measurements, left ventricular diastolic parameters and left ventricular myocardial performance index (MPI) were measured. The left ventricular MPI was calculated as (isovolumic contraction time + isovolumic relaxation time) / aortic ejection time by Doppler. The urine fluoride levels of fluorosis patients were significantly higher than control subjects as expected (1.9 ± 0.1 mg/l vs 0.4 ± 0.1 mg/l respectively; P < 0.001). Isovolumic relaxation time (IVRT) and deceleration time (DT) were significantly higher in fluorosis patients than in controls (for IVRT 106.9 ± 15.6 ms vs 96.7 ± 12.2 ms; P < 0.001 and for DT 211.7 ± 30.7 ms vs 188.0 ± 30.0 ms; P < 0.001, respectively). MPI was significantly higher in fluorosis patients than in controls (0.62 ± 0.15 ms vs 0.49 ± 0.10 ms; P < 0.001, respectively). We have shown that chronic fluorosis patients had left ventricular diastolic and global dysfunctions.

Effect of Endemic Fluorosis on Hematological Parameters

Although so many studies exist on effect of fluoride on hematological parameters in experimental animals, a few studies have been conducted to investigate the effects of chronic fluorosis on hematological parameters in humans' subjects with endemic fluorosis. So we aimed to determine the hematological parameters in patients with endemic fluorosis. The study group consisted of 60 patients with endemic fluorosis (27 females, 33 males, and mean age 33.4 ± 9.6 years). An age-, gender-, and body mass index-matched control group was composed of 34 healthy volunteers (11 females, 23 males with a mean age 32.6 ± 5.6 years). Urine fluoride levels of fluorosis patients were significantly higher than control subjects as expected (0.42 ± 0.09 vs 1.92 ± 0.14 mg/l, respectively; P < 0.001). There were no statistically significant differences between the fluorosis group and control group with respect to hematological parameters (complete blood count and ferritin). We concluded that chronic fluorosis has no effect on hematological parameters in patients with endemic fluorosis.

Aortic Elasticity is Impaired in Patients with Endemic Fluorosis

Sixty-three patients with endemic fluorosis (36 males/27 females; mean age 33.9 +/- 8.6 years) and 45 age-, sex-, and body mass index-matched healthy controls (30 males/15 females; mean age 32.7 +/- 8.8 years) were included in this study. Aortic stiffness indices, aortic strain (AS), aortic distensibility (AD), and aortic strain index (ASI) were calculated from the aortic diameters measured by echocardiography and blood pressure obtained by sphygmomanometry. The urine fluoride levels of fluorosis patients were significantly higher than control subjects as expected (1.9 +/- 0.1 mg/l vs. 0.4 +/- 0.1 mg/l, respectively; P < 0.001). AS and AD were significantly lower in fluorosis patients than in the controls (for AS 5.3 +/- 3.6 vs. 8.0 +/- 3.4%; P < 0.001 and for AD 0.2 +/- 0.1 vs. 0.3 +/- 0.1 cm(2) dyn(-1) 10(-3); P < 0.001, respectively). In contrast, significantly higher ASI was observed in fluorosis patients than in the controls (3.4 +/- 0.6 vs. 3.0 +/- 0.4; P < 0.001, respectively). The results of our study demonstrate that elastic properties of ascending aorta are impaired in patients with endemic fluorosis.

Oxidative stress in cases of chronic fluoride intoxication

This study was conducted to find out the level of oxidative stress and effect of supplementation of vitamin C, D and Calcium on levels of SOD, serum and urinary fluoride in children residing in endemic fluorosis area. For this the fluoride belt of Jaipur district was selected. The parameters selected were Super oxide dismutase, serum fluoride and urinary fluoride. The study was conducted on one hundred children, selected from four areas (25 from each area) consuming water containing 1.2, 2.4, 5.6 and 13.6 mg/l of fluoride. Drinking water fluoride, serum and urinary fluoride were measured by Ion selective electrode method. Serum SOD by Xanthine oxidase method using kit of Ransod (kit cat. No. SD125). The post treatment values showed a significant reduction in serum fluoride and SOD. Urinary fluoride levels increased significantly in post treatment stage. The results revealed a normal SOD levels in all groups but an increasing trend was observed with increasing fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C showed a significant reduction in serum fluoride and SOD and increase in urinary fluoride. A high positive correlation between pretreatment and post treatment group was observed in serum fluoride, SOD and urinary fluoride (P < 0.05). The study indicated an increasing oxidative stress in cases of fluorosis with increasing drinking water fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C resulted a significant reduction in serum fluoride and SOD and increase in urinary fluoride.

Absorción sistémica de flúor en niños secundaria al cepillado con dentífrico fluorado

The effect of the fluoride in the caries prevention is strongly linked to its topical action. When the fluoride is ingested, its anticaries effect is weak and, in addition, it can cause side effects such as dental fluorosis in children. The toothbrushing with fluoride dentifrice is a suitable procedure to provide the topical fluoride, but in small children there is risk of inadvertent swallowing. The main goal of this study is to quantify the fluoride levels in urine after toothbrushing with fluoride dentifrice. A sample of 115 children between 5 to 8 years was randomly selected. The pH, as well as creatinine and fluoride levels were analyzed in the urine excreted before and two hours after toothbrushing with fluoride dentifrice. The fluoride/creatinine (F/Cr) ratio was used to minimize the variations of the fluoride levels in urine due to the different rates of secretion. For the statistical analysis, the average, the standard deviation and the T test were used for the variables with normal distributions, and nonparametric tests were applied for the variables with non normal distribution. The average amount of dentifrice was 1192 mg (SD: 421). The variables pH and creatinine showed similar values in the two samples of urine analyzed (pH: 6,35 and 6,36; creatinine: 0,76 g/l and 0,81 g/l). Nevertheless, the F/Cr ratio increased significantly after toothbrushing, ranging from 0.61 to 1.25 mg/g. The use of fluoride dentifrice is related to a significant increase of the fluoride concentration in urine in children.

Prevalence and manifestations of water-born fluorosis among schoolchildren in Kaiwara village of India: a preliminary study.

Background: Fluorosis is an endemic condition with prevalence in 19 states and union territories in India. It is an urgent task to survey the fluorosis-related problems in these regions. Objective: To study the clinical manifestations of water-born fluorosis among schoolchildren in Kaiwara village of India. Methods: A cross-sectional study was conducted in all schoolchildren between 1 st and 7 th standard studying in Kaiwara village, Karnataka State, India. Parameters studied included fluoride ingestion through drinking water, fluoride excretion through urine, clinical features of fluorosis. These included dental staining, genu valgum, goiter, and conjunctival xerosis. Fluoride in water and urine samples was estimated using an ion meter. Results: Of the 416 schoolchildren studied, 24.0% children had dental fluorosis, 11.4% children had genu valgum, 20.9% had goiter, and 10.3% had xerosis of the conjunctiva. One hundred children passed high levels of fluoride in urine, while 90% of water samples consumed by the local residents contained high levels of fluoride. Conclusion: It was proved that water-born fluorosis is endemic in Kaiwara village. The endemic prevalence of the syndrome of fluorosis among school children was characterized by dental mottling, genu valgum, endemic goiter, and xerosis of the conjunctiva.

COL1A2 gene polymorphisms (Pvu II and Rsa I), serum calciotropic hormone levels, and dental fluorosis

To investigate the relationship between dental fluorosis, polymorphisms in the COL1A2 gene, and serum calciotropic hormone levels. We conducted a case-control study among children between 8 and 12 years of age with (n = 75) and without (n = 165) dental fluorosis in two counties in Henan Province, China. The PvuII and RsaI polymorphisms in the COL1A2 gene were genotyped using the PCR-RFLP procedure. Calcitonin and osteocalcin levels in the serum were measured using radioimmunassays. Children carrying the homozygous genotype PP of COL1A2 PvuII had a significantly increased risk of dental fluorosis (OR =4.85, 95% CI: 1.22-19.32) compared to children carrying the homozygous genotype pp in an endemic fluorosis village (EFV). However, the risk (OR = 1.07, 95% CI: 0.45-2.52) was not elevated when the control population was recruited from a non-endemic fluorosis village. Additionally, fluoride levels in urine and osteocalcin levels in serum were found to be significantly lower in controls from non-endemic villages compared to cases. However, the differences in fluoride and osteocalcin levels were not observed when cases were compared to a control population from endemic fluorosis villages. This study provides the first evidence of an association between polymorphisms in the COL1A2 gene with dental fluorosis in high fluoride exposed populations. Future studies are needed to confirm the association.

Determination of fluoride in human whole blood and urine by gas chromatography-mass spectrometry

We developed a simple and sensitive method for determination of fluoride in human whole blood and urine using gas chromatography-mass spectrometry (GC-MS). Fluoride was alkylated with pentafluorobenzyl bromide in a mixture of acetone and phosphate buffer (pH 6.8). The derivative obtained was analyzed by GC-MS in the positive-ion electron-impact mode. The lower limit of detection for the compound was 0.5 mg/l for both matrices. The calibration curve for fluoride was linear over the concentration range of 1–100 mg/l. The precision and accuracy of the method were evaluated, and relative standard deviation was within 10%. Using this method, levels of fluoride in whole blood and urine were determined in a case of poisoning caused by hydrofluoric acid exposure.

The Relationship between High Fluoride Intake and Nephrolithiasis

Background and Aims: One poorly studied factor that probably has a significant influence on the development of calcium oxalate renal calculi is the presence of urinary het-erogeneous nucleants, since the urine of all individuals is per-manently supersaturated with calcium oxalate. In this study we investigated and evaluated the role of calcium fluoride (CaF₂) as seed crystals for the induction of calcium oxalate urolith development. Materials and Methods: Induction of calcium oxalate urolith development in the presence of CaF₂seed crystals was studied using batch crystallizers and flow systems in the presence of both fluoride ions and CaF₂seed crystals. The effects of diverse crystallization inhibitors were also evaluated. Results: The results suggest that the forma-tion of CaF₂crystals in urine, even considering the excretion of high amounts of fluoride ions, is very unlikely. Nevertheless, when formed, CaF₂crystals acted as heterogeneous nucleants of calcium oxalate crystals. This effect was delayed in the presence of the crystallization inhibitors phytate and pyrophosphate at concentrations similar to those normally found in urine. Citrate, chondroitin sulfate and pentosan polysulfate were not inhibitory. Conclusion: High urinary fluoride levels alone do not cause calcium oxalate stone development; other factors must also exist, such as retention of CaF₂ crystals and deficit of crystallization inhibitors.

Fluoride Levels in Water, Animal Feeds, Cow Milk, Cow Urine and Milk Production of Dairy Cattle from Kiambu and Thika Districts in Kenya

Kiambu and Thika Districts are situated in Central part of Kenya. Most of the available land is suitable for agricultural use. Majority of the farmers are small scale or subsistence dairy farmers. Intake of excess fluoride in water, feed and mineral supplements may adversely affect health, reproduction and production in dairy cattle. The objectives of this study were to investigate the levels of fluoride in water, urine, milk and animal feeds and mineral salts from dairy farms in Kiambu and Thika, as well as to relate milk yield and fluoride intake. Samples were analyzed using electroanalysis technique. The overall mean fluoride concentration in feeds from societies was 60.9 + 132.0 mg F/kg. The mean fluoride concentration in feeds from Nderi, Kikuyu, Chania, Limuru, Kiambaa and Lari co-operative societies were: 19.5 +11.3 (n=19) 24.1+28.6 (n=22), 55.2+73.7 (n=18), 67.6+93.4 (n=15), 91.9+226.3 (n=24) and 203.4+ 243.2 (n=6) mg F/kg respectively. Individual dairy co-operative society and the type of sample significantly (p

Fluorose osseuse : à propos d’un cas

The authors report a case of skeletal fluorosis described in a 60 years old man living in south-west Tunisian. The main clinical sign is a severe functional legs disability. Radiographic examination has shown a diffused osteocondensation, with cervical spine degenerative discopathy, a pelvis bilateral osteoarthritis and an interosseous membrane ossification of forearms and legs. The skeletal fluorosis diagnosis has been confirmed by high serum and urinary fluoride levels.

Recovery From Skeletal Fluorosis (an Enigmatic, American Case)

A 52-year-old man presented with severe neck immobility and radiographic osteosclerosis. Elevated fluoride levels in serum, urine, and iliac crest bone revealed skeletal fluorosis. Nearly a decade of detailed follow-up documented considerable correction of the disorder after removal of the putative source of fluoride (toothpaste). Skeletal fluorosis, a crippling bone disorder, is rare in the United States, but affects millions worldwide. There are no data regarding its reversibility. A white man presented in 1996 with neck immobility and worsening joint pains of 7-year duration. Radiographs revealed axial osteosclerosis. Bone markers were distinctly elevated. DXA of lumbar spine (LS), femoral neck (FN), and distal one-third radius showed Z scores of +14.3, +6.6, and -0.6, respectively. Transiliac crest biopsy revealed cancellous volume 4.5 times the reference mean, cortical width 3.2 times the reference mean, osteoid thickness 25 times the reference mean, and wide and diffuse tetracycline uptake documenting osteomalacia. Fluoride (F) was elevated in serum (0.34 and 0.29 mg/liter [reference range: <0.20]), urine (26 mg/liter [reference range: 0.2-1.1 mg/liter]), and iliac crest (1.8% [reference range: <0.1%]). Tap and bottled water were negative for F. Surreptitious ingestion of toothpaste was the most plausible F source. Monitoring for a decade showed that within 3 months of removal of F toothpaste, urine F dropped from 26 to 16 mg/liter (reference range: 0.2-1.1 mg/liter), to 3.9 at 14 months, and was normal (1.2 mg/liter) after 9 years. Serum F normalized within 8 months. Markers corrected by 14 months. Serum creatinine increased gradually from 1.0 (1997) to 1.3 mg/dl (2006; reference range: 0.5-1.4 mg/dl). Radiographs, after 9 years, showed decreased sclerosis of trabeculae and some decrease of sacrospinous ligament ossification. DXA, after 9 years, revealed 23.6% and 15.1% reduction in LS and FN BMD with Z scores of +9.3 and +4.8, respectively. Iliac crest, after 8.5 years, had normal osteoid surface and thickness with distinct double labels. Bone F, after 8.5 years, was 1.15% (reference range, <0.1), which was a 36% reduction (still 10 times the reference value). All arthralgias resolved within 2 years, and he never fractured, but new-onset nephrolithiasis occurred within 9 months and became a chronic problem. With removal of F exposure, skeletal fluorosis is reversible, but likely impacts for decades. Patients should be monitored for impending nephrolithiasis.

Osteosclerosis due to endemic fluorosis

Endemic water borne fluorosis is a public health problem in Isparta, a city located in southern Turkey. In order to investigate the association between osteosclerosis and fluorosis, we retrospectively screened the results of lumbar spine and femur neck bone mineral density (BMD) of 1500 patients who were examined before, for any reason in between 2001-2003. Sixty nine patients (67 females and 2 males, mean age 52.6+/-10.2) with vertebra T-scores>or=+2 were found only except a patient with osteoid osteoma in the femur neck (femur T-score+6.64). Thirty-four of the patients could be reexamined with lateral vertebra BMD and investigated for fluorosis and the other etiologic causes of osteosclerosis. Of 34 patients, 14 had either mottled tooth enamel or urine fluoride level greater than 1.5 mg/l. Other etiologic causes were hypothyroidism (2), hypoparathyroidism (1), history of lumbar fracture (1), use of retinoids (1), vitamin D (7), oral calcium preparations (9), and bisphosphanates (3). Lateral lumbar vertebral T-score was greater than+2 in 12 patients (35.3%). Femur T-score was greater than+2 in 7 patients (20.6%). Fourteen patients (41.2%) had lateral vertebral or femur T-score>or=+2. Five (35.7%) of these patients had signs of fluorosis, as discussed before. Mean body mass index of individuals with fluorosis was 36.4+/-7.9 and this result was significantly higher than other osteosclerotic subjects (31.6+/-4.4). In conclusion we believe that approximately one third of the osteosclerosis in our region was due to endemic skeletal fluorosis and obesity may enhance this osteosclerotic type bone changes in endemic fluorosis.