Fluorosis Of Teeth Research Articles

Usage of Fluoridated toothpaste in children and Fluorosis of permanent teeth

Objective: To determine the usage of fluoridated toothpaste in children and the presence of fluorosis in permanent teeth. Study Design: Descriptive cross-sectional study. Place and Duration: This study was undertaken in Hayatabad Model School Hayatabad Peshawar, from 1st March, 2022 to 31st October, 2022. Methodology: Eighty (N=80) school going children of both genders from 11-16 years age with healthy and vital teeth were included in this study. Children with chronic diseases were excluded from this study. Ingestion of childhood fluoride toothpaste and degree of fluorosis was recorded by using a questionnaire. Fluorosis was graded on basis of clinical examination by Dean Index. The data was analyzed using statistical package for social sciences (SPSS) version 20. Numerical variables were presented as mean and standard deviation whereas categorical variables were mentioned as numbers and percentages. Results: Mean age of children was 13.15 with 71.25% females (n=57) and 28.75% (n=23) males. 40.6% children (n=65) had dental fluorosis. Majority of children had mild fluorosis 65% (n=52), followed by moderate fluorosis (12.5%, n=10) and severe fluorosis (3.8%, n=3). 36.3% of the children ingested toothpaste in their early childhood (n=29) whereas 63.7% did not ingest tooth paste (n=51). Conclusion: Dental fluorosis is more common in those children who have a history of ingestion of fluoride tooth paste in their childhood. Keywords: Dental Fluorosis, Fluoride, Dental Caries, Dean Index, Childhood, Tooth Paste, Community Water Fluoridation.

Fine‐tuning of fully‐aromatic polyamide membrane for fluorinated water purification

AbstractHigh concentrations of fluoride in drinking water can lead to fluorosis of teeth and bones and other serious diseases, while nanofiltration is an attractive technique for fluoride removal. Interfacial temperature can determine the monomer diffusion rate in interfacial polymerization (IP) process, thereby tuning the structure of membrane such as thickness, pore size and surface charge. Herein, a fully‐aromatic polyamide nanofiltration membrane with desirable separation performance was customized by interface temperature. The resulting membrane exhibits a flux of 6 L m−2 h−1 bar−1 and the molecular weight cut‐off is 211 Da, most importantly, a 90.3% F− rejection to underground water, indicating that the membrane has application potential in underground water treatment. This work helps to better understand the effects of interface temperature on the IP process and provides a new strategy to address the drinking water problem.

Aesthetic problem in the appearance of permanent teeth in children and adolescents - dental fluorosis.

Introduction: Dental fluorosis is a disease caused by excessive consumption of fluoride and its deposition in the enamel during odontogenesis. The result of this process is the appearance on the surface of permanent teeth of unsightly stains of various colors depending on the intensity of damage to the enamel. Deterioration of dental aesthetics can significantly affect the quality of life of patients affected by dental fluorosis.Aim of the study: The purpose of this study is to present contemporary knowledge on the cause, diagnosis and treatment of dental fluorosis.Materials and methods: Medical databases of the National Center for Biotechnology Information/PubMed and Google Scholar were analyzed by typing the following keywords: dental fluorosis, fluoride poisoning, amelogenesis, enamel. When analyzing the literature, data from 25 scientific articles from the last five years (2017-2022) were used.Results: In most of the articles, the authors emphasize the significant association between consumption of fluoridated water and fluorosis of permanent teeth. The literature is unanimous regarding the choice of minimally invasive treatment procedures when dental fluorosis needs to be treated.Conclusions: Dental fluorosis is a significant aesthetic and functional problem among affected children. Education about the etiology of dental fluorosis and ways to avoid it should be constantly disseminated among children's caregivers. Patients affected by this problem should be under the constant care of a dentist.

Clinical condition of teeth and dentition in children and adolescents with cerebral palsy

BACKGROUND: Literature and statistical data reveal the increasing incidence of psychoneurological diseases (PND) and thus dental pathologies with PND in children and adolescents. Thus, the authors examined the structures and frequency of dental defects and deformities in patients with PND. Children and adolescents with PND aged 718 years are at high risk for the development of dental pathologies, and oxidative stress and immune system disorder present major associations with the pathogenesis of dental pathologies.
 AIM: To determine the structure and frequency of dental defects and deformities in children and adolescents with PND and study the etiopathogenetic factors and mechanism of pathology formation to guide the development of preventive measures.
 MATERIAL AND METHODS: The study comprehensively analyzed the data of 299 patients aged 718 years, of which 143 were diagnosed with PND based on the International Classification of Disease 10th Revision (main group; МG) and 156 somatically healthy patients with dental pathologies (control group; CG). The participants were divided into two subgroups: 75 patients aged 712 years (52.44%; МG-1) and 68 patients aged 1318 years (47.55%; МG-2) from the main group (MG) and 65 (41.66%; CG-1) and 91 (58.33%; CG-2) patients from the CG of the respective age groups.
 RESULTS: The incidence rates of caries in the temporary teeth of MG-1 and CG-1 were 97.33% and 84.61% and in the permanent teeth of MG-2 and CG-2 were 95.58 and 87.91%, respectively. In the pre-eruptive period, the rates of dental lesions were as follows: hypoplasia, 20.97%; impaired dentition, 49.65%; primary adentia, 47.55%; anomalies of the completeness of teeth, 64.33%; endemic fluorosis of teeth, 2.79% in patients with PND; and 12.17%, 12.17%, 26.92%, 11.53%, and 0.6% in children and adolescents in CG, respectively (p 0.0001): disappearance of dental hard tissues, 9.09%; dental injuries, 24.47%; enamel necrosis, 7.7%; enamel erosion, 17.5% of patients with MG. In children and adolescents of CG, only tooth trauma was noted in 7.7% and enamel necrosis in 1.3%. In patients with PND, 49.6% had distal occlusion; 37.8%, cross occlusion; 31.6%, neutral occlusion; 29.9%, deep incisor occlusion; 25.9%, deep incisor malocclusion; 54.5%, narrowing of the lower dentition; 43.3%, crowding of teeth in the lower jaw; 26.6%, diastemas; and tremas, 23.8%.
 CONCLUSION: Non-carious lesions of the teeth and a shift in the timing of the development of temporary and permanent teeth are more common in MG than in CG and lead to impaired dental anatomy and disrupt the aesthetics of smiles, speech, etc. Moreover, hypertrophic gingivitis and local periodontitis were characteristic of children with severe PND, who are at high risk for dental pathologies associated with oxidative stress and genetically related immune system disorders, especially in older children with PND.

Adsorption Characteristics and Charge Transfer Kinetics of Fluoride in Water by Different Adsorbents

Water containing high concentrations of fluoride is widely distributed and seriously harmful, largely because long-term exposure to fluoride exceeding the recommended level will lead to fluorosis of teeth and bones. Therefore, it is imperative to develop cost-effective and environmentally friendly adsorbents to remove fluoride from polluted water sources. In this study, diatomite (DA), calcium bentonite (CB), bamboo charcoal (BC), and rice husk biochar (RHB) were tested as adsorbents to adsorb fluoride (F‐) from water, and this process was characterized by scanning electron microscopy (FEI-SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). The effects of pH, dosage, and the initial mass concentration of each treatment solution upon adsorption of F‐ were determined. Kinetic and thermodynamic models were applied to reveal the mechanism of defluoridation, and an orthogonal experiment was designed to obtain the optimal combination of conditions. The results show that the surfaces of CB, BC, and RHB have an irregular pore structure and rough surface, whereas DA has a rich pore structure, clear pores, large specific surface area, and high silica content. With regard to the adsorption process for F‐, DA has an adsorption complex electron interaction; that of CB, BC, and RHB occur mainly via ion exchange with positive and negative charges; and CB on F‐ relies on chemical electron bonding adsorption. The maximum adsorption capacity of DA can reach 32.20 mg/g. When the mass concentration of fluoride is 100 mg/L, the pH value is 6.0 and the dosage is 4.0 g/L; the adsorption rate of F‐ by DA can reach 91.8%. Therefore, we conclude that DA soil could be used as an efficient, inexpensive, and environmentally friendly adsorbent for fluoride removal, perhaps providing an empirical basis for improving the treatment of fluorine-containing water in the future.

The main criteria of dental morbidity in children under seven years of age living in regions with different fluoride content in drinking water

Relevance. Early caries is one of the most prevalent childhood diseases worldwide. Up to 32% of three-year-olds have tooth decay, the prevalence of caries in 6-7-year-old children in different cities of Russia increases to 65%, while 55.7% of children have caries of permanent teeth. In order to improve the quality of dental care, it is necessary to receive information about the prevalence and intensity of dental diseases, taking into account medical geography. Purpose – to assess caries and fluorosis incidence rate in primary teeth, to determine the hygiene index and the level of dental care for children under seven years old living in regions with different fluoride concentrations in drinking water.Materials and methods. The study conducted dental examinations of 150 children living in the South-Eastern Administrative District of Moscow aged 1 to 6 years and of 200 children living in Krasnogorsk aged 1 to 6 years. The study included the patients based on the developed inclusion criteria and informed voluntary parent consent. We entered the data into the registration card, which noted the dental formula, the prevalence and intensity of caries, the hygiene index according to Fedorov-Volodkina, the level of dental care according to P.A. Leus (1987).Results. Children living in an area with a low fluoride concentration in drinking water show the first signs of caries by the first year of age, then there is a significant increase, observed in the group of 3and 6-year-olds. The prevalence of caries in 1-year-old children living in an endemic focus of fluorosis is almost two times lower than in children living in an area with a reduced content of fluorides in drinking water, in 3-4-year-old children – 1.5 times lower, and in 5-6-year-old children 2 times lower. Along with this, 16-year-old children living in the focus of endemic fluorosis, Krasnogorsk, Moscow region, revealed fluorosis of primary teeth with a prevalence of 27%.Conclusions. The results indicates the need to increase the frequency and quality of patient education and increase the level of dental care.

A simple microabrasion technique as aesthetic approach on fluorosis of anterior teeth

ABSTRACT Dentistry treatment is not only focused on restoring the function of mastication but also onthe aesthetic problem. Fluorosis is one of the aesthetic problems caused by excessive fluoride intakeduring email formation and produced color changes on the surface of the email. Fluorosis was notaffected by the aesthetics but also influenced the confidence of the patient. The Microabrasion techniqueis an option for fluorosis because it is conservative treatment with good results. A 20-year-old womanwho came to the Dental Conservation clinic complained that she wants to remove the brown color andwhite spots seen on the front teeth, which significantly interfere with her appearance. Based on clinicalexamination, many cavities were found in the back teeth of the upper and lower jaw. The results of thehistory and clinical study revealed that the patient had fluorosis in her teeth. Microabrasion was carriedout using Opalustre (ultradent). This material was applied to the tooth surface and rubbed using anapplicator (opal bristle) for 60 seconds. Then applied fluoride gel paste with finishing cup opal.Treatment results showed changes in tooth color, brown and white patches disappeared. Microabrasionis the first choice for aesthetic treatment in fluorosis and has shown satisfying results to restore thepatient's aesthetics problem. KEYWORDS: Fluorosis, microabrasion technique

Dental fluorosis and its burden in India-revisiting a forgotten chapter

“Flouride” mineral is essential for the normal development of bone and teeth. However, its presence in excess of the required limit results in fluorosis of bone (skeletal) and teeth (dental). It is a dominating public health issue in India due to the geographical fluoride belt across numerous states. Dental fluorosis is characterised by the staining and pitting of tooth/teeth. Despite fluoride’s anticariogenic potential, when present in excess amounts, deteriorates aesthetics and cripples the physical, mental and social health of individuals. Numerous government-led initiatives are in place to optimize fluoride levels, unfortunately, with limited coverage and constrained time frame. The overview is an endeavour to assemble the breathing information on dental fluorosis and the obliviousness towards this condition devastating many lives in India. In this manner, stressing on the squeezing need of educational and dental treatment mediations alongside rebuilding of defluoridation programs across the nation.

Effectiveness of a microabrasion technique using 16% HCL with manual application on fluorotic teeth: A series of studies.

BACKGROUNDDental fluorosis is caused by excessive fluoride ingestion during tooth formation. As a consequence, there is a higher porosity on the enamel surface, which causes an opaque look.AIMThe aim of this study was to identify a dental intervention to improve the smile in patients with tooth fluorosis. Additional aims were to relate the stain size on fluorotic teeth with the effectiveness of stain removal, enamel loss and procedure time using a manual microabrasion technique with 16% hydrochloric acid (HCL).METHODSAn experimental study was carried out on 84 fluorotic teeth in 57 adolescent patients, 33 females and 24 males, with moderate to severe fluorosis. The means, standard deviations and percentages were analyzed using nonparametric statistics and ArchiCAD 15 software was used for the variables including stain size and effectiveness of stain removal.RESULTSThe average enamel loss was 234 µm and was significantly related to the procedure time categorized as 1-4 min and 4.01-6 min, resulting in a P > 0.000. The microabrasion technique using 16% HCL was effective in 90.6% of patients and was applied manually on superficial stains in moderate and severe fluorosis. Procedure time was less than 6 min and enamel loss was within the acceptable range.CONCLUSIONMicroabrasion is a first-line treatment; however, the clinician should measure the average enamel loss to ensure that it is within the approximate range of 250 µm in order to avoid restorative treatment.

Фтор в природних водах Одещини: медико-географічний аналіз

The study of fluorine content in the natural waters of the Odesa region was carried out. The content of fluorine in the waters of the centralized and non-centralized drinking waters supply of the Odesa region and the city of Odesa is determined. Areas with low and high fluorine content are found. Very low fluorine content is determined in Kiliyskyi, Bilyaivskyi, Kodimskyi and Savranskyi districts of the Odessa region. High fluorine content (above MAC) is determined in the Tarutinskiy and Arzizkyi districts. Correlation dependence of fluorine content in drinking water of the Odesa region and indicators of the prevalence of dental diseases (caries and fluorosis of teeth) of the population of the region and the city are established. It is determined that for most districts of the region there is a relationship between the content of fluorine in drinking waters and dental health. In some areas, this dependence is not sufficiently expressed, which is due to the geochemical and ecological characteristics of the territory. It is revealed that for the population of Odesa, who use water with very low fluoride content, high indicators of the disease for caries and fluorosis of teeth are characteristic, which is connected with the allocation of industrial areas with significant anthropogenic loading, including fluorine compounds. One of the possible causes of dental disease, even with optimal fluorine content in drinking water, can be the combination of its action with other chemical elements. Key words: fluorine, drinking water, Odesa region, Odesa city, caries and fluorosis of teeth.

Bond strength and micro-computed tomographic evaluation of pre-coated brackets

Abstract Objectives The aim of the present study was to assess and compare the shear bond strength (SBS) of metal pre-coated orthodontic brackets bonded to fluorotic and non-fluorotic teeth treated with three different etching techniques. A second aim was to determine the volume of adhesive remaining on the tooth at debond using micro-computed tomography (μCT). Methods Ninety extracted premolars were selected to include 45 fluorotic (test group) and 45 non-fluorotic (control group) teeth. Each group was divided into three subgroups of 15 each, which were treated as follows: 1) micro-etched; 2) acid-etched; and 3) both micro-etched and acid-etched. A bonding agent was applied to the prepared surfaces; pre-coated and light-cured brackets were attached to all teeth. An Instron universal testing machine was used to record the debonding force. Specimens were then scanned using a microCT to evaluate the amount of adhesive remaining on the teeth. The significance of the statistical tests was pre-determined at p < 0.05. Results Two-way ANOVA showed that fluorosis of teeth had no influence on the SBS (p = 0.165) whereas the volume of adhesive remnants was significantly higher in the control group compared with the test group (p < 0.001). Conclusions Fluorosis had no influence on the SBS of brackets, whereas it had a negative influence on retaining adhesives onto the tooth surfaces.

Fluoride removal from diluted solutions by Donnan dialysis using full factorial design

Excessive fluoride concentration in potable water can lead to fluorosis of teeth and bones. In the present study, Donnan dialysis (DD) is applied for the removal of fluoride ions from diluted sodium fluoride solutions. A four factor two level (24) full factorial design was used to investigate the influence of different physico-chemical parameters on fluoride removal efficiency (Y F ) and fluoride flux (J F ) through anion exchange membrane. The statistical design determines factors which have the important effects on Donnan dialysis performance and studies all interactions among the considered parameters. The four significant factors were initial fluoride concentration, feed flow rate, temperature and agitation speed. The experimental results and statistical analysis show that the temperature and agitation speed have positive effects on fluoride removal efficiency and the initial fluoride concentration has a negative effect. In the case of fluoride flux, feed flow rate and initial concentration are the main effect and all factors have a positive effect. The interaction between studied parameters was not negligible on two responses. A maximum fluoride removal of 75.52% was obtained under optimum conditions and the highest value of fluoride flux obtained was 2.4 mg/cm2·h. Empirical regression models were also obtained and used to predict the flux and the fluoride removal profiles with satisfactory results.

Amoxicillin use during early childhood and fluorosis of later developing tooth zones

Amoxicillin use has been reported to be associated with developmental defects on enamel surfaces. This analysis assessed the association between amoxicillin use and fluorosis on late-erupting permanent teeth. As part of the Iowa Fluoride Study, subjects were followed from birth to 32 months with questionnaires every 3-4 months to gather information on fluoride intake and amoxicillin use (n = 357 subjects for this analysis). Permanent tooth fluorosis on late-erupting zones was assessed by three trained dentists using the fluorosis risk index (FRI) at approximately age 13. A case was defined as fluorosis if a subject had at least two FRI classification II zone scores of 2 or 3. Chi-square tests and logistic regression were used, and relative risks (RRs) and odds ratios (ORs) were calculated. There were 113 cases and 244 controls. In bivariate analyses, amoxicillin use from 20 to 24 months significantly increased the risk of fluorosis on FRI classification II zones [44.2 percent versus 30.4 percent, [RR = 1.45, 95 percent confidence interval (CI) 1.05-2.04], but other individual time periods did not. Multivariable logistic regression confirmed the increased risk of fluorosis for amoxicillin use from 20 to 24 months (OR = 2.92, 95 percent CI = 1.34-6.40), after controlling for otitis media, breast-feeding, and fluoride intake. Amoxicillin use during early childhood could be a risk factor in the etiology of fluorosis on late-erupting permanent tooth zones, but further research is needed.

Associations Between Dental Fluorosis of the Permanent and PrimarvJ Dentitions

Relatively little is known about associations between primary and permanent tooth fluorosis. In this study, associations between dental fluorosis of the permanent and primary dentitions were assessed. Subjects (n = 601) are in the Iowa Fluoride Study, which included fluorosis examinations of the primary and early-erupting permanent dentitions by trained dentist examiners. Relative risks, correlations, and logistic regression assessed associations between permanent tooth fluorosis and primary molar fluorosis. Ten percent had primary molar fluorosis at age 5; 36% had definitive (mostly mild), 28% questionable, and 36% no permanent incisor fluorosis at age 9. Those with primary molar fluorosis were significantly more likely to have definitive permanent incisor fluorosis (76% vs. 32%), and permanent molar fluorosis (59% vs. 16%). The strong association between primary and permanent tooth fluorosis is independent of level of fluoride intake. Detection of primary tooth fluorosis in pre-school children should alert clinicians and parents to the high likelihood of subsequent fluorosis in the permanent dentition.

Associations between Intakes of Fluoride from Beverages during Infancy and Dental Fluorosis of Primary Teeth

Objective: We describe associations between primary tooth fluorosis status and intakes of beverages and fluoride from these beverages during infancy.Methods: Subjects (n = 677) are members of the Iowa Fluoride Study, a cohort of young children followed from birth. Food and nutrient intakes were obtained from 3-day diet records. Diets were analyzed at 6 weeks, 3, 6, 9, 12 and 16 months and cumulatively for 6 weeks through 16 months of age. Primary tooth fluorosis was assessed at 4.5–6.9 years of age and defined as present or absent. Multiple logistic regression analyses were used to develop models to predict fluorosis status.Results: Water-based beverage intakes were higher in subjects with fluorosis than in those without. Specifically, higher intakes of water used to reconstitute formulas at 3, 6 and 9 months; any intake of water as a beverage at 16 months; and higher intakes of combined 100% juice and miscellaneous beverages at 16 months were positively associated with fluorosis (p < 0.05). Fluoride intakes from water sources were also higher in subjects with fluorosis than in those without. Specifically, higher intakes of fluoride from water used to reconstitute formulas at 3, 6, 9 and 12 months and for 6 weeks through 16 months, and higher intakes of fluoride from water as a beverage at 16 months and for 6 weeks through 16 months were positively associated with fluorosis (p < 0.05).Conclusion: Infant beverages, particularly infant formulas prepared with fluoridated water, can increase the risk of fluorosis in primary teeth.

Primary Tooth Fluorosis and Amoxicillin Use During Infancy

It has been speculated that amoxicillin use could be associated with enamel defects, but there have been few studies of this possible relationship. This study assessed the association between amoxicillin use during the first year of life and primary tooth fluorosis. Subjects (n = 490) were recruited at birth and followed prospectively with a series of questionnaires to gather information on fluoride intake and amoxicillin use. Primary tooth fluorosis was assessed by calibrated examiners at approximately 5 years of age. Amoxicillin use for 6 weeks to 3 months and 3 months to 6 months significantly increased the risk for fluorosis of primary second molars in bivariate analyses. However, after controlling for fluoride intake, the adjusted risks of fluorosis were not significant for amoxicillin use. No other antibiotics were significantly associated with fluorosis in the bivariate analyses. In multivariate analyses with logistic regressions, only fluoride intake was statistically significantly related to fluorosis. Fluoride exposure was the sole predictor of primary tooth fluorosis in a multivariate model. However, bivariate results suggest that amoxicillin could play a contributing role in the development of primary tooth fluorosis, especially for children exposed to lower levels of fluoride. An investigation of the relationship between amoxicillin intake and fluorosis of permanent teeth is warranted.

Primary tooth fluorosis and fluoride intake during the first year of life.

Few studies in North America have assessed dental fluorosis of the primary dentition and few, if any, anywhere have assessed the relative importance in fluorosis etiology of fluoride intake during different time periods or from multiple sources. The purpose of this paper is to report on analyses relating estimated prenatal fluoride intake and fluoride intake during different parts of the first year of life to primary tooth fluorosis. As part of The Iowa Fluoride Study, subjects were recruited at birth and studied longitudinally. Trained examiners assessed dental fluorosis for children aged 4-7 years using the Tooth Surface Index of Fluorosis (TSIF) adapted for the primary dentition. Detailed parent questionnaires at childbirth were used to estimate prenatal fluoride intake and questionnaires sent at 6 weeks and 3, 6, 9, and 12 months were used to estimate fluoride intake during the first year of life (combined fluoride intake from water, food and beverage, supplements, and dentifrice). There were 504 children with prenatal and at least four of the five postnatal responses with complete data. Fluorosis prevalence was 12.1%, occurring primarily on the second primary molars. Receiver operating characteristic (ROC) curves and logistic regression were used to assess the importance of different time periods' fluoride intake. In bivariate analyses, fluoride intake during each time interval was individually significantly related to fluorosis occurrence. For multivariate analyses, the period from 6 to 9 months was most important individually (P = 0.0001), and no other period was jointly statistically significant. Results suggest that the middle of the first year of life is most important in fluorosis etiology for the primary dentition in this setting.

Prevalence of Dental Fluorosis in the Primary Dentition

This paper presents data on the prevalence of primary tooth fluorosis among children residing in Iowa, and the relationships between fluorosis prevalence and selected measures of fluoride exposures. Children in the study cohort were followed prospectively during the first year of life. This study assessed their home water fluoride concentrations and use of fluoride dentifrice or dietary fluoride supplements. A total of 637 children (320 females and 317 males) were examined for fluorosis using a modification of the TSIF index at age 4 1/2 to 5 years, with 90.4 percent having intact primary dentitions. 74 children (11.6%) had fluorosis present on one or more of their primary teeth, and 71 children (11.1%) had two or more teeth affected. Nearly all fluorosis was mild, with the primary second molar teeth most commonly affected. Fluorosis was significantly associated with higher water fluoride concentration, but not with the use of dentifrice or fluoride supplements. The results of this study show that primary tooth fluorosis is relatively uncommon, but is most frequently seen on the posterior teeth, particularly the primary second molars, which form at later stages of development. This finding suggests that primary tooth fluorosis is mostly a postnatal phenomenon, and is associated with higher water fluoride levels.

Prevention of brick tea fluorosis in rats with low-fluoride brick tea on laboratory observation

To test whether low-fluoride brick tea can prevent the occurrence of fluorosis, rats had access only to a specially prepared low-fluoride brick tea for 1 year. The daily fluoride intake, fluoride metabolism, tissue distribution and development of tooth fluorosis were observed at 4-monthly intervals, at the end of months 4, 8 and 12, respectively. Rats drinking ordinary brick tea (F − 503.5 mg/kg) served as control. The daily intake of fluoride in the ordinary brick tea group was 0.3 mg, and this group developed dental fluorosis characterized as brown and white horizontal marks at the end of month 8, and white chalky dental fluorosis developed at the end of month 12. The total incidence was 75%. In contrast, the daily fluoride intake of the low-fluoride brick tea (F − 210 mg/kg) group was 0.19 mg, and this group did not develop any signs of dental fluorosis. Fluoride distribution was mainly retained in the bone tissue, and about half of the absorbed fluoride was excreted via urine and feces. The results suggest that this low-fluoride brick tea did not induce fluorosis in rats and can be used as an effective control measure for humans.

Effect of fluoridated salt intake in infancy: a blind caries and fluorosis study in 8th grade Hungarian pupils.

Salt fluoridation is effective at inhibiting caries, but fluorosis prevalence data are deficient. The purpose was to undertake a blind study of caries and tooth mottling in 8th grade school pupils from south-east Hungary who had resided (test) or not resided (control), until November 1985, in a 350 ppm F-/kg domestic salt-fluoridated area during their early years of life. In Szeged, blind clinical caries and anterior tooth mottling scoring (+10% repeats) of 49 previously salt-fluoridated (mean age 14.14 years) and 59 non-salt-fluoridated subjects (mean age 14.08 years) were undertaken by one examiner, in June 1997. In addition, radiographic and photographic recordings were taken. In Glasgow, four dental and two lay staff scored the projected 35 mm colour transparencies (+10% repeats) of each pupil's six upper anterior teeth, for tooth mottling. All clinical, radiographic and photographic data were then analysed. Mean DMFS scores were 9.18 (SD=10.72) for test users and 4.51 (SD=6.24) for control users (P<0.01) and, based on repeat observations, clinical reliability=0.99; X-ray reliability=0.95. Clinically, three test children had fluorosis of 10 teeth, with eight teeth in two controls. Photographic scoring by the clinical examiner gave a 97.2% clinical match, while photographic agreements for all four dentist pairs were 92.5%-97.2%, with lay observers' agreements at 89.8%. For both groups, 10% repeats produced 98.5% agreements. In a sole test case "fluorosis" photographic unanimity was obtained, and non-unanimous "possible fluorosis" was recorded by two to four panel members for only three other test and two control subjects. No evidence was found that significant anterior tooth fluorosis resulted in subjects exposed previously to 350 ppm F-/kg domestic salt from birth to 2.3-4.8 years of age. However, no caries benefit was demonstrated after the 11.5-year salt fluoridation gap. Caries differences seemed social class-related, city-based controls having less disease than rural test subjects, in spite of an identical F- tablet regimen in all schools from 1987, until subjects were 10 years old. These data emphasise (a) the superiority of sustained community-delivered fluoridation and (b) the need to maintain constant fluoride delivery to tooth surfaces, certainly well beyond 10 years of age.