Examiner reliability in fluorosis scoring: a comparison of photographic and clinical methods

OBJECTIVE

To assess examiner reliability when scoring dental fluorosis in Malaysian children using clinical (Dean's Index) and photographic methods.

METHOD

The upper central incisors of 111 children were examined both clinically and photographically for fluorosis status using Dean's index. Twenty children were re-examined after a two-week interval for intra-examiner reliability by a single examiner. In addition, two independent examiners and the clinical examiner scored 111 photographic images of the same children in a standardized manner. Fluorosis scores were compared individually between examiners for both clinical and photographic scoring. Examiner reliability was assessed using both simple and weighted kappa statistics at tooth level. Sensitivity, specificity, positive-negative predictive values and a Receiver Operating Characteristic (ROC) curve were also calculated to determine the accuracy of the test.

RESULTS

Across the three examiners, the prevalence of fluorosis (Dean's score ≥ 2) using photographs was lower (ranged from 23% to 26%) than the prevalence recorded by clinical examination (30%). The kappa score for intra-examiner reliability for the duplicate clinical examination was excellent (0.89). Inter-examiner reliability between the photographic method and the clinical examination (gold standard) for each examiner was substantial with weighted kappa values ranging from 0.74 to 0.77. The photographic method indicated higher specificity (99%) than sensitivity (79%) and the area under the ROC curve was also high (0.89) which suggests good accuracy of the diagnostic test.

CONCLUSION

These results suggest that photographic examination of fluorosis on central incisors can be recorded with good examiner reliability. The recorded fluorosis prevalence was lower using the photographic scores.

The impact of oral health status on the oral health-related quality of life (OHRQoL) of 12-year-olds from children's and parents' perspectives

OBJECTIVES

To assess the effect of dental caries, periodontal status and dental fluorosis on the oral health-related quality life (OHRQoL) of 12-year-olds and to assess the agreement between parents and children on the children's OHRQoL relative to the children's oral health status.

METHODS

A two-stage sampling method was used to select a sample of 12-year-olds from Binzhou, China. Their oral health status was recorded using the DMFT, CPI and Dean's Index. The Child Perception Questionnaire 11-14 (CPQ(11-14)) and the Parental Perception Questionnaire (PPQ) were administered to the children and their parents, respectively, to assess the children's oral health-related quality of life.

RESULTS

The data used in the analysis were collected from 1,120 children. The prevalence of tooth decay was 31.6% and that of dental fluorosis was 29.7%; 4.1% of the children had healthy gums and 52.4% had dental calculus. There was a moderate to good correlation between the CPQ and PPQ (ICC = 0.51-0.68). Having dental fluorosis and brushing teeth less than twice a day negatively influenced the emotional well-being domain of the CPQ, but was not related to this domain of the PPQ. Having calculus, dental fluorosis, brushing teeth less than twice a day and having dental visits negatively influenced the social well-being domain of the CPQ, but only tooth brushing was related to this domain of the PPQ.

CONCLUSIONS

Children's self-reported CPQ(11-14) scores were more strongly associated with their oral health status and OHRQoL than their parents' PPQ scores were, especially in the social and emotional well-being domains. Having caries, dental fluorosis or dental calculus negatively affected children's oral health-related quality of life.

Effects of enamel fluorosis and dental caries on quality of life

The objectives of this study were to determine the impact of enamel fluorosis and dental caries on oral health-related quality of life (OHRQoL) in North Carolina schoolchildren and their families. Students (n = 7,686) enrolled in 398 classrooms in grades K-12 were recruited for a onetime survey. Parents of students in grades K-3 and 4-12 completed the Early Childhood Oral Health Impact Scale (ECOHIS) and Family Impact Scale (FIS), respectively. Students in grades 4-12 completed the Child Perceptions Questionnaire (CPQ8-10 in grades 4-5; CPQ11-14 in grades 6-12). All students were examined for fluorosis (Dean's index) and caries experience (d2-3fs or D2-3MFS indices). OHRQoL scores (sum response codes) were analyzed for their association with fluorosis categories and sum of d2-3fs and D2-3MFS according to ordinary least squares regression with SAS procedures for multiple imputation and analysis of complex survey data. Differences in OHRQoL scores were evaluated against statistical and minimal important difference (MID) thresholds. Of 5,484 examined students, 71.8% had no fluorosis; 24.4%, questionable to very mild fluorosis; and 3.7%, mild, moderate, or severe fluorosis. Caries categories were as follows: none (43.1%), low (28.6%), and moderate to high (28.2%). No associations between fluorosis and any OHRQoL scales met statistical or MID thresholds. The difference (5.8 points) in unadjusted mean ECOHIS scores for the no-caries and moderate-to-high caries groups exceeded the MID estimate (2.7 points) for that scale. The difference in mean FIS scores (1.5 points) for the no-caries and moderate-to-high groups exceeded the MID value (1.2 points). The sum of d2-3fs and D2-3MFS scores was positively associated with CPQ11-14 (B = 0.240, p < .001), ECOHIS (B = 0.252, p ≤ .001), and FIS (B = 0.096, p ≤ .01) scores in ordinary least squares regression models. A child's caries experience negatively affects OHRQoL, while fluorosis has little impact.

Use of clinical bleaching with 35% hydrogen peroxide in esthetic improvement of fluorotic human incisors in vivo

AIM

The aim of the study was to evaluate esthetic improvement with the use of 35% hydrogen peroxide clinical bleaching as related to the different grades of enamel fluorosis in vivo and to study adverse effect of clinical bleaching with 35% hydrogen peroxide on teeth and gingiva.

MATERIALS AND METHODS

A total of 60 children of different grades of fluorosis were included in the study. With 35% hydrogen peroxide-based dual activated bleaching system, in-office vital teeth bleaching was carried out for each subject. Clinical evaluation for improvement in esthetics, effect on teeth and gingiva were performed for each child during preoperative, immediate postoperative and later 6 months postoperative period. For evaluation and comparison, all the collected data were subjected to statistical analysis.

RESULTS

Although in all the subjects, partial shade relapse was seen over a period of time, good homogeneous and esthetic results were seen in very mild and mild cases. A total of 35% hydrogen peroxide in-office bleaching has no adverse effect on teeth and gingiva.

CONCLUSION

Comparing all the three groups who participated in the study, 35% hydrogen peroxide in-office bleaching seems to be very effective in very mild and mild forms of fluorosis.

CLINICAL SIGNIFICANCE

In very mild and mild forms of fluorosis, in-office vital tooth bleaching with 35% hydrogen peroxide is the most conservative and effective approach in esthetic improvement.

The impact of a dental program for maternal and infant health on the prevalence of dental fluorosis

PURPOSE

This study's purpose was to investigate the prevalence of dental fluorosis in children, whose parents had participated in an oral health program when the children were between zero and three years old, residing in a city with fluoridated water.

METHODS

Group 1 consisted of 128 eight- to 12-year-olds whose parents had visited a program on at least five occasions when the children were zero to three years old and received education about tooth-brushing and the proper use of fluoridated toothpaste in this young age group. The prevalence of dental fluorosis in the permanent maxillary incisors, using the Thylstrup-Fejerskov index, in Group 1 was compared to that of an age-matched group of children (n=128) whose parents had not participated in the program (Group 2).

RESULTS

Group 1 mothers reported higher education levels (P<.05). Group 1 children had a significantly lower prevalence (∼42 percent) and severity (P<.05) of dental fluorosis than those in the control group (∼61 percent).

CONCLUSION

Children whose parents participated in a dental program that included counselling on the proper amount of fluoridated toothpaste when their children were between zero and three years old presented less frequently with dental fluorosis than a control group when examined at eight to 12 years old.

Associations between fluorosis of permanent incisors and fluoride intake from infant formula, other dietary sources and dentifrice during early childhood

OBJECTIVES

The authors describe associations between dental fluorosis and fluoride intakes, with an emphasis on intake from fluoride in infant formula.

METHODS

The authors administered periodic questionnaires to parents to assess children's early fluoride intake sources from beverages, selected foods, dentifrice and supplements. They later assessed relationships between fluorosis of the permanent maxillary incisors and fluoride intake from beverages and other sources, both for individual time points and cumulatively using area-under-the-curve (AUC) estimates. The authors determined effects associated with fluoride in reconstituted powdered infant formulas, along with risks associated with intake of fluoride from dentifrice and other sources.

RESULTS

Considering only fluoride intake from ages 3 to 9 months, the authors found that participants with fluorosis (97 percent of which was mild) had significantly greater cumulative fluoride intake (AUC) from reconstituted powdered infant formula and other beverages with added water than did those without fluorosis. Considering only intake from ages 16 to 36 months, participants with fluorosis had significantly higher fluoride intake from water by itself and dentifrice than did those without fluorosis. In a model combining both the 3- to 9-months and 16- to 36-months age groups, the significant variables were fluoride intake from reconstituted powder concentrate formula (by participants at ages 3-9 months), other beverages with added water (also by participants at ages 3-9 months) and dentifrice (by participants at ages 16-36 months).

CONCLUSIONS

Greater fluoride intakes from reconstituted powdered formulas (when participants were aged 3-9 months) and other water-added beverages (when participants were aged 3-9 months) increased fluorosis risk, as did higher dentifrice intake by participants when aged 16 to 36 months.

CLINICAL IMPLICATIONS

Results suggest that prevalence of mild dental fluorosis could be reduced by avoiding ingestion of large quantities of fluoride from reconstituted powdered concentrate infant formula and fluoridated dentifrice.

Perceptions and concerns about dental fluorosis as assessed by tooth surface index of fluorosis among high school children in an area of endemic fluorosis--Kaiwara

PURPOSE

The aim of this study was to assess the perceptions and concerns about dental fluorosis among high school children in an area that is endemic to fluorosis, and to correlate the children's perceptions of dental fluorosis with different scores of tooth surface index of fluorosis.

MATERIALS AND METHODS

The study was conducted among 155 children affected with fluorosis, aged between 12 and 16 years, studying in all four high schools of Kaiwara, Karnataka, India. Fluorosis was assessed on labial surfaces of maxillary anterior teeth using tooth surface index of fluorosis, and the data were collected using a self-administered pretested questionnaire that was given to the study subjects. Analysis was performed using frequency distribution, chi-square test and Spearman's correlation coefficients.

RESULTS

Significant high correlations were found between tooth surface index of fluorosis scores and the perception of the importance of the condition (r = 0.226, chi2 = 72.065, P < 0.01), considering the condition to be a disadvantage in the future (r = 0.166, chi2 = 73.097, P < 0.05) and also the last visit to the clinician for the condition (r = -0.184, chi2 = 14.252, P < 0.05).

CONCLUSION

Perceptions and concerns of dental fluorosis among this age group of children appear to be of aesthetic concern making it essential to focus on this issue and to intervene.

Disparities in oral health-related quality of life in a population of Canadian children

OBJECTIVES

To assess socioeconomic disparities in the oral health-related quality of life in a group of Canadian children.

METHODS

Data were obtained as part of a study designed to assess the functional and psychosocial impact of traumatic dental injury. Clinical data were collected on a random sample of children during a school-based dental screening program that included measures of dental decay experience, treatment needs, dental trauma, fluorosis, and malocclusion. Children with dental trauma and a comparison group of trauma-free children were selected for follow-up. Their parents were mailed a questionnaire concerning the child's personal and family characteristics. Also enclosed was a questionnaire for the child that contained a short form of the Child Perceptions Questionnaire (CPQ) 11-14. Bivariate and multivariate analyses were undertaken to determine whether there were disparities in oral health-related quality of life according to household income.

RESULTS

Complete data were collected from 370 children. Mean CPQ11-14 scores showed a gradient across income categories with children from low income households having poorer oral health-related quality of life. Children from households containing only one adult also had higher scores than children living with two or more adults. In both linear and logistic regression analyses household income and family structure remained significant predictors of CPQ11-14 scores after controlling for oral disease variables. Further analyses suggested that oral disorders had little impact on the health-related quality of life of higher income children but a marked impact on lower income children. The highest mean CPQ11-14 scores were observed among low income children with the more severe levels of oral disease.

CONCLUSION

The data indicate that in this group of children there were socioeconomic disparities in oral health-related quality of life. A potential explanation may be differences in psychological assets and psychosocial resources.

[A socioeconomic classification and the discussion related to prevalence of dental caries and dental fluorosis]

OBJECTIVE

The aim of this study was to evaluate the relationship between a socioeconomic classification model and prevalence of dental caries and dental fluorosis in Piracicaba, Sâo Paulo, Brazil.

METHODS

For this classification five indicators were used (family monthly income, number of residents in the same household, parents' formal educational level, type of housing and occupation of person responsible for the family). A scoring system was used in order to arrange in a hierarchy, 812 12 year old school children distributed between six different social classes. Volunteers were examined in the school's back patio under natural light with a dental mirror, by two examiners calibrated for DMFT index (dental caries) and T-F (dental fluorosis). The qui-square test (p<0.01) was used in the statistical analysis for the association of DMFT and the dental fluorosis and between the socioeconomic variable and the proposed social classes.

RESULTS

The DMFT average was 1.7, while 31.4%, of the children had dental fluorosis (T-Fe"1).

CONCLUSION

With respect to socioeconomic class a statistically significant association was only verified with dental caries.

Prevalence and severity of dental fluorosis among students from João Pessoa, PB, Brazil

The aim of this study was to determine the prevalence and severity of dental fluorosis among 12-15-year-old students from João Pessoa, PB, Brazil before starting a program of artificial fluoridation of drinking water. The use of fluoridated dentifrice was also surveyed. A sample of 1,402 students was randomly selected. However, 31 students refused to participate and 257 were not permanent residents in João Pessoa, thus leaving a final sample of 1,114 students. Clinical exams were carried out by two calibrated dentists (Kappa = 0.78) under natural indirect light. Upper and lower front teeth were cleaned with gauze and dried, and then examined using the TF index for fluorosis. A questionnaire on dentifrice ingestion and oral hygiene habits was applied to the students. The results revealed that fluorosis prevalence in this age group was higher than expected (29.2%). Most fluorosis cases were TF = 1 (66.8%), and the most severe cases were TF = 4 (2.2%). The majority of the students reported that they had been using fluoridated dentifrices since childhood; 95% of the participants preferred brands with a 1,500 ppm F concentration, and 40% remembered that they usually ingested or still ingest dentifrice during brushing. It was concluded that dental fluorosis prevalence among students in João Pessoa is higher than expected for an area with non-fluoridated water. However, although most students use fluoridated dentifrices, and almost half ingest slurry while brushing, the majority of cases had little aesthetic relevance from the professionals' point of view, thus suggesting that fluorosis is not a public health problem in the locality.

Perception of dental fluorosis and other oral health disorders by 12-year-old Brazilian children

AIM

The aim of this study was to verify the perception of dental fluorosis as an oral health problem by 12-year-old Brazilian children and to evaluate if they were able to detect other oral disorders.

METHODOLOGY

The sample consisted of 401 schoolchildren. Firstly, clinical examinations were performed using a visual method under natural light. After that, children answered a questionnaire with the purpose of assessing the self-perception of their oral health problems. Next, the volunteers were shown a photo album containing 24 photographs, and had to match each photo with a severity scale.

RESULTS

The prevalence of fluorosis was 18.2%; 81.8% of this total in fluorosis scale T-F 1. Of the 401 children, 48.9% (n = 196) answered oral health problems related to concerns, such as aesthetic appearance or pain. Among them, only two children, both with fluorosis T-F 2, correlated their problems with the presence of stained teeth. As regards the photo album analysis, the children considered photos showing fluorosis T-F 7-9 as the most severe, whereas the photo of an orally healthy patient was considered the least severe.

CONCLUSION

Children did not show negative perception of dental fluorosis, except for dental fluorosis at severe levels (T-F 7-9), and were mainly able to detect aesthetic or pain-related problems.

Agreement amongst examiners assessing dental fluorosis from digital photographs using the TF index

OBJECTIVE

To compare the scoring of dental fluorosis by experienced examiners from digital photographs using the TF index.

BASIC RESEARCH DESIGN

120 images were selected from 703 photographs obtained during a clinical trial (Tavener et al., 2004). The selection process was stratified so that the full range of defects seen in the main study was included. The children, aged 8-10 years, were from deprived areas of Manchester, England with fluoride levels in the drinking water of less the 0.1 ppm F. The photographs of the upper and lower anterior sextants were taken after cleaning and drying the teeth. The examiners were identified by searching Medline for individuals who had previously used the TF index or had experience of scoring dental fluorosis. Of the 12 examiners identified, 10 agreed to take part. Each examiner was provided with identical CDs containing a PowerPoint presentation of the images. Twelve images were duplicated and interspersed amongst the 120 images to assess intra examiner agreement. Each examiner was also supplied with a table listing the criteria and illustrations for each of the TF index scores (Fejerskov et al., 1988).

RESULTS

The prevalence of fluorosis (TF > 0) amongst the 10 examiners ranged from 43% to 70% and from 2% to 13% for the more severe scores (TF 3 or 4). Paired agreements amongst subject scores for the 10 examiners, measured using a weighted Kappa score, ranged from 0.40 to 0.71.

CONCLUSION

It is concluded that although the criteria for the TF index are well defined, it is possible that examiners may interpret the criteria in different ways and conditions in which images are viewed may need to be standardised. This study may explain some of the differences in the prevalence and severity of fluorosis reported in different studies. There is a need to standardise the methods used to score dental fluorosis.

Improving esthetically objectionable human enamel fluorosis with a simple microabrasion technique

Mild-to-moderately severe enamel fluorosis (EF) is an unsightly maturation-phase dental disorder. Despite extensive epidemiological studies on EF, little is known about individual treatment options. This study was carried out to determine whether a simple microabrasion technique is effective in improving the esthetics of EF. Patients with a variety of severities were treated using a water-cooled fine diamond polishing bur at high speed to remove the surface enamel layers. Photographs of the affected teeth before and after treatment were shown by computer to a panel of three judges (two lay and one experienced), who rated the appearance of the teeth using a newly developed visual analog scale. The severity of EF was rated randomly and blind for 52 individual teeth (26 before and 26 after treatment). Reteated-measures analysis of variance was used to analyze the results. The lay judges rated the appearance of the teeth with EF as significantly more objectionable before treatment. All judges found a significant improvement in the severity of EF after treatment. Using a newly developed visual analog scale, our study indicates that EF of an objectionable nature can be significantly improved with a simple microabrasion technique, thus conserving tooth structure and minimizing the cost of treating EF.

Changes in dental fluorosis following the cessation of water fluoridation

OBJECTIVES

To determine changes in the prevalence of dental fluorosis, and in perceptions of aesthetic concerns due to dental fluorosis after water fluoridation ceased.

METHODS

Schoolchildren in second and third grades were examined in 1993-94, 1996-97 and 2002-03 to determine changes in the prevalence of dental fluorosis following fluoridation cessation of the public water supplies in 1992. The Thylstrup-Fejerskov Index (TFI) was used to quantify dental fluorosis. Perceptions of aesthetics were assessed by questionnaires which were sent home to parents. Residence and dental histories were confirmed on all children to determine the extent of exposure to all types of fluorides. Comparisons between the three surveys were used to establish the influence of fluoridated water and other fluoride sources on the occurrence and severity of dental fluorosis. Aesthetic ratings from parents were used to assess the aesthetic conditions of maxillary anterior teeth across the three surveys.

RESULTS

When fluoride was removed from the water supply in 1992, the prevalence and severity of TFI scores decreased significantly from the 1993-94 survey cycle when compared with the 1996-97 and 2002-03 survey cycles. The use of fluoride supplements and fluoride dentifrice also decreased during this study period. Analyses were unable to determine the influence of these different fluoride exposures on the changes in TFI scores over time. Comparisons of aesthetic ratings from parents between survey cycles failed to show any significant differences.

Attitudes to fluorosis and dental caries by a response latency method

BACKGROUND

Understanding socially relevant attitudes to fluorosis and dental caries is important. Previous studies have concentrated mainly on aesthetic implications.

AIMS

To investigate social judgements beyond the aesthetic, made when viewing digitally manipulated extraoral images of dental fluorosis of varying degrees of severity and images of dental caries.

METHODOLOGY

Using a response latency technique, which allowed both the direction and strength of attitudes to be measured, 40 volunteers made judgements on 144 image/characteristic combinations.

RESULTS

Participants made social judgements which extended beyond the aesthetic to factors such as sociability, reliability and cleanliness. Judgements on mild fluorosis were not markedly different from those made about the same individual with normal enamel, but severe fluorosis had a significant negative impact on social judgements. Untreated dental caries was judged less favourably than normal enamel and mild fluorosis.

CONCLUSIONS

Attribution of characteristics that go beyond the aesthetic are significantly influenced by altered tooth appearance.

Subjective impacts of dental caries and fluorosis in rural Ugandan children

OBJECTIVE

Describe the oral health related quality of life among a group of children in rural Uganda and compare impacts on oral health related quality of life associated with dental caries and fluorosis.

BASIC RESEARCH DESIGN

Cross-sectional clinical and questionnaire analytical study.

PARTICIPANTS

Proportional sample of 174 12 year olds attending primary schools in a rural sub-county of Uganda.

OUTCOME MEASURES

Clinical assessments using WHO basic methods and the Thylstrup and Fejerskov index of Fluorosis (TFI). Child Oral Health Related Quality of Life data collected with self-administered child perception questionnaire (CPQ11-14).

RESULTS

Two thirds of children reported a dental impact 'often' or 'everyday'. The mean number of impacts per child at this threshold was 2.6 and the mean total CPQ11-14 score was 25.8 (sd 21.1). Mean DMFT was 0.68. No children had fillings. Forty-one children had dental fluorosis with 10 having scores greater than 2. CPQ11-14 showed acceptable criterion validity and reliability. The number of sites with gingivitis or the presence of calculus or trauma were not associated with summary measures of CPQ11-14 whereas having any dental caries or treatment experience was associated with higher total scores and more impacts. Socially noticeable fluorosis (TFI >2) was associated with more impacts but not with higher total scores.

CONCLUSIONS

Despite low levels of oral disease these children experience appreciable impacts on oral health related quality of life. The greatest burden was associated with dental caries and to a lesser extent, fluorosis.

A visual analog scale for measuring dental fluorosis severity

BACKGROUND

To date, no continuous scale exists for measuring the severity of dental fluorosis (DF).

OBJECTIVES

The authors developed and validated a visual analog scale (VAS) for DF. They tested the scale in clinical (DF-endemic area) and laboratory settings.

METHODS

Dentists and nondentists (23 per group) were asked to grade the DF severity in photographs of 23 anterior teeth with different DF levels (using a 100-millimeter VAS) to create a VAS for DF. Statistical analysis was performed to validate the new scale. The authors used clinical and laboratory (unerupted third molars) analyses to assess the usefulness of the VAS.

RESULTS

The authors used an intraclass correlation coefficient (ICC) to assess the interexaminer (ICC = .79: good agreement) and intraexaminer (.88 < ICC < .97: excellent agreement) reliability during creation of the scale. They used the Spearman rank correlation (r(s)) to validate the VAS against the gold standards (that is, the Thylstrup-Fejerskov index [TFI] and Dean's index [DI]) (the results showed excellent or good correlation for 45 examiners). Two dentist examiners clinically tested the new VAS, and the results showed excellent (r(s) = .922, P < .001) correlation and excellent ICC between the examiners (ICC = .96), as well as good ICC between the TFI and the VAS for DF (ICC = .6). The laboratory study showed better correlation between fluoride concentration and the VAS for DF than between fluoride concentration and the TFI.

CONCLUSION

Because of its simplicity, precision and utility in statistical applications, the VAS for DF can be useful in DF studies.

Responder and Nonresponder Analysis for a Caries Prevention Program

To be able to generalize studies, it is important to know whether responders and nonresponders differ significantly. These data are usually not available. To assess whether responders and nonresponders differed significantly, 319 first and second graders in Greifswald, Germany took part in a compulsory dental school examination. Their parents completed a questionnaire on oral health topics and were asked to decide about their children's participation in a school-based caries prevention program plus anonymous scientific evaluation. The 91 children who were not allowed to participate (nonresponders) were older (mean 8.5 years) than the 228 responders (mean 8.1 years; p < 0.001), mostly because of a few older children having repeated a grade. In an age-adjusted analysis, nonresponders exhibited in 21 of 30 indices of higher caries and plaque values, less preventive measures and a lower rate of participation. The difference in caries in the permanent dentition and fluorosis reached statistical significance. This study suggests that nonresponders to caries prevention programs might comply less with preventive measures and exhibit poorer oral health than responders: a result which has to be taken into account in research and prevention programs in the community.

The prevalence and severity of fluorosis and other developmental defects of enamel in children who received free fluoride toothpaste containing either 440 or 1450 ppm F from the age of 12 months

OBJECTIVE

To assess the impact of a programme regularly supplying free fluoride toothpaste to children on the prevalence and severity of fluorosis and other developmental defects of enamel.

DESIGN

Randomised, controlled, parallel three-group clinical trial. Two groups received toothpaste containing either 440 or 1450 ppm F; the third group received no intervention. Children were supplied with toothpaste and advice on its use from the age of 12 months until they were 5-6 years old. The participants were a sub sample of those involved in a study that considered the caries benefits of providing free fluoride toothpaste. They were eligible if they completed the main study, lived in four of the nine districts involved and attended schools with 6 or more eligible participants.

SETTING

Children from the north west of England consuming drinking water containing less than 0.1 ppm F were examined in primary schools.

PARTICIPANTS

3731 children completed the main study. Of the 1833 children in the four selected districts, 927 were from schools with six or more participants.

METHOD

Digital images encompassing the upper and lower anterior sextants were taken of each child when they were 8-9 years old.

MAIN OUTCOME MEASURES

Developmental defects of enamel and dental fluorosis (TF index) were recorded on upper central incisors from wet and dry images.

RESULTS

A total of 703 children were included in the data analysis. In the 1450 ppm F (n=218), 440 ppm F (n = 226) and control (n = 259) groups the prevalence of dental fluorosis (TF > 0) was 17%, 15% and 12% for the wet (p > 0.05) and 26%, 24% and 25% for the dry (p > 0.05) photographs respectively. The prevalence of TF scores 2 or 3 (highest score) was 5%, 4% and 2% and for the wet (p > 0.05) and 7%, 4% and 5% for the dry (p > 0.05) photographs respectively. All subjects identified with TF score 3 were found in the group using the 1450 ppm F toothpaste (3 wet and 4 dry) and there were statistically significant differences between the three groups for both wet (p = 0.03) and dry photographs (p < 0.01). However, the pairwise comparisons between the groups failed to attain statistical significance. The highest prevalence and severity of demarcated opacities was seen in the control group and for the wet photographs the difference between the three groups attained statistical significance (p = 0.04). For both the wet and dry photographs the prevalence of any enamel defects (including fluorosis) and large demarcated or TF score 3 was similar for the three groups (p > 0.05).

CONCLUSION

Previously it has been reported that only the provision of 1450 ppm F toothpaste provides anticaries benefits in a programme of this type. This benefit is accompanied by a slight increase in prevalence of TF score 3 but not the overall prevalence of developmental defects of enamel. Careful targeting and implementation of a programme of this type is required to maximise benefits and minimise risks of fluoride exposure.

The presence of dental fluorosis in the permanent dentition in Doha

The main purpose of this study is to draw attention to the presence and the severity of dental fluorosis in Doha (Qatar) through the high level of registered cases of fluorosis found among the groups examined. Of 4800 people aged 8-50 years, 2654 (55.29%) had dental fluorosis of some degree. This problem urgently requires more studies throughout the country to provide an accurate assessment.

Is fluoride concentration in dentin and enamel a good indicator of dental fluorosis?

Despite some studies correlating dental fluorosis (DF) and fluoride (F) concentration in dental enamel, no information is available about DF and dentin F concentration. Our objective was to determine the correlation between teeth F concentration and DF severity in unerupted human 3rd molars, and the correlation between dentin and enamel F concentrations in the same tooth. Ninety-nine 3rd molars were studied-53 from Fortaleza, Brazil (F water, 0.7 ppm), 22 from Toronto (1.0 ppm), and 24 from Montreal (0.2 ppm). DF severity was evaluated according to the Thylstrup-Fejerskov Index, while F concentration was analyzed by Instrumental Neutron Activation Analysis. DF severity varied between TF0 and TF4, while F concentration ranged between 39 and 550 ppm in enamel and 101 and 860 ppm in dentin. Our results showed correlation between dentin F concentration and DF (r(S) = 0.316, p = 0.001), but no correlation between enamel F concentration and DF (r(S) = 0.154, p = 0.133). No correlation was observed between dentin and enamel F concentrations in the same tooth (r(S) = 0.064, p = 0.536).

Socio-demographic features and fluoride technologies contributing to higher fluorosis scores in permanent teeth of Canadian children

OBJECTIVE

To examine levels of fluorosis among children in two Canadian communities exposed to fluoride.

BACKGROUND

One community had discontinued fluoride, the other had maintained it. Water supplies, however, were fluoridated for all the children when their esthetically important teeth were mineralized.

METHODS

We examined 8,277 children to assess Thystrup-Fejerskov Index (TFI) scores. Multivariate Poisson regression models were used to identify the relationship between TFI and water fluoride status, age, gender, SES, and dietary and fluoride exposure histories (supplements, rinses, toothpaste amount, tooth brushing frequency, and tooth brushing starting age). Parent(s) completed questionnaires.

RESULTS

Overall, levels of fluorosis were low to mild, with residents of the fluoridation-ended communities having marginally higher TFI scores than those of the still-fluoridated community. Females had higher TFI scores than males. Children aged 10 years or more had higher TFI scores than younger children. Consuming bottled water between birth and 6 months of age was protective. Exposure to fluoridation technologies was consistently associated with fluorosis experience. Children who began brushing with fluoride toothpaste between their first and second birthdays had higher TFI scores than those who began between their second and third birthdays, regardless of daily brushing frequency. Children who regularly used supplements had higher TFI scores than those who did not. Children with a college-educated father had higher TFI scores than those whose fathers had less education.

CONCLUSIONS

Higher fluoride exposure slightly increased the likelihood that a child had a higher TFI score, especially when more fluoridation technologies were used at home.

Perception of dental fluorosis amongst Ethiopian children and their mothers

This study was conducted in three Ethiopian Rift Valley villages known for endemic fluorosis. Three-hundred-and-six adolescents (12-15 years) and 233 mothers participated. The aim was to study dental fluorosis in the youngsters and to assess the extent of agreement between clinical and self-rated discoloration and pitting of teeth, and also the level at which dental fluorosis is perceived as a problem both by children and their mothers. The children (154 M and 152 F) gave a simple self-assessment of tooth-color and quality of their teeth, and were subsequently examined for dental fluorosis. Finally, four color photographs of teeth with dental fluorosis (TF-scores 2, 3, 5, and 7) were used as references during a structured oral interview of the children, as well as their mothers. At TF score > or = 2, the prevalence of dental fluorosis on maxillary central incisors was 72% and 37% at TF score > or = 4. The mean TF score was significantly higher among boys than among girls of unemployed fathers compared to children of employed fathers. The likelihood of reporting problems with dental appearance increased with increasing individual TF scores. The child/mother pairs found teeth with TF scores 2 and 3 esthetically acceptable, while teeth with TF scores 5 and 7 were considered unacceptable. Mothers were more critical of severe fluorosis than were their children.

Ecotoxicological risks associated with land treatment of petrochemical wastes. I. Residual soil contamination and bioaccumulation by cotton rats (Sigmodon hispidus)

Petrochemical waste contains both organic and inorganic contaminants that can pollute soil and may pose significant ecological risks to wildlife. Petrochemical waste typically is disposed of in land treatment units, which are widespread throughout Oklahoma and the United States. Few studies have been conducted evaluating possible toxicity risks to terrestrial organisms residing on these units. In this study, the extent of soil contamination with fluoride (F), metals, and organic hydrocarbons, the bioaccumulation of F and metals in cotton rats (Sigmodon hispidus), the relationship between contaminants in soil and in tissues of cotton rats, and the level of potentially toxic polycyclic aromatic hydrocarbons (PAHs) in soil were determined on land treatment units. Over a 2-yr period, cotton rats and soils were collected and analyzed from 5 land treatment and matched reference units. The number of land treatment units with soil metal contamination (in parentheses) included: Cr, Cu, Pb (5). Al, As, Ni, Sr, Zn (4). Ba (3). and Cd, V (2). The number of land treatment units with soil PAH contamination (in parentheses) were naphthalene, phenanthrene, benzo[g,h,i]perylene (3). acenaphthene, anthracene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[a]pyrene, indeno[1,2,3-c,d]pyrene, dibenz[a,h]anthracene (2). and acenaphthylene, fluorene, fluoranthene, benzo[k]fluoranthene (1). Total PAH and total petroleum hydrocarbons (TPH) were elevated at all five land treatment units. Mean sums of benzo[a]pyrene (BaP) equivalents (BaPequiv ) were not affected on

Fluorosis development in seven age cohorts after an 11-month break in water fluoridation

This study used an 11-month break in water fluoridation to identify the time when developing incisors are most sensitive to fluorosis development. The study was based in Durham, NC, where an interruption to water fluoridation occurred between September, 1990, and August, 1991. A total of 1896 children was dentally examined. Fluorosis was measured by the TF index, and parents or guardians completed a questionnaire on demographics and fluoride history. Age cohorts ranged from those born 5 years before the break, to those born 1 year after the resumption of fluoridation. Fluorosis prevalence for seven age cohorts whose birth years ranged from 1985-86 to 1991-92 was 57.1, 62.3, 33.0, 32.3, 39.8, 30.2, and 36.8%, respectively. Children aged from birth to 3 years at the break, and those born 1 year after it, had less fluorosis than those aged 4-5 years at the break.

Degree of fluorosis in areas of South Africa with differing levels of fluoride in drinking water

The purpose of this study was to study the relationship between degree of fluorosis and varying fluoride concentrations in the drinking water in a relatively dry region in South Africa. A strong positive association was found between drinking water fluoride levels and fluorosis but only up to a level of approximately 2.0 ppm for areas with a high average daily temperature (approximately 79 degrees F). The results indicate that the optimum drinking water fluoride concentration for a region with a high average daily temperature should be less than 1.00 ppm.

Caries experience and caries predictors--a study of Tanzanian children consuming drinking water with different fluoride concentrations

The aim of this investigation was to assess the role of predictors of caries experience among children in urban and rural areas of northern Tanzania. Children of the different communities had varying dietary habits and consumed water with varying fluoride (F) concentration. Subjects (n=256) aged 9-14 years were examined in high-F areas (3.6 mg F/l, Arusha and Arusha Meru, n=101) and low-F areas (<0.4 mg F/l, Moshi and Kibosho, n=155). Dental caries was assessed under field conditions using the decayed, missing, filled teeth (DMFT) index and the WHO criteria. The prevalence of caries was 14%. The mean DMFT score was 0.22 (n=256), the range between areas 0.07-0.66. Carious lesions were mainly observed in mandibular first molars. Logistic regression analyses indicated that subjects in the high-F and urban Arusha municipality were at a significantly higher risk of dental caries than children in the low-F areas (odds ratio [OR] 2.6). Controlling for ethnicity, children in urban areas were at higher risk for caries (OR 5.4) than children living in low-F rural Kibosho.

Caries reduction in belgian 12-year-old children related to socioeconomic status

This study compares dental caries reduction in Belgian 12-year-old children of different socioeconomic status in 1983 and 1998. Moreover, the relative effect of dental health factors on caries reduction is estimated. In the region of Brussels, children in the 7th grade at the same schools participated in cohort 1983 (n = 533) and in cohort 1998 (n = 496). DMFT, DMFS, and dental fluorosis were clinically recorded. The socioeconomic status of the children was established on the basis of their parents' education and profession. Data on children's home-based and professional dental health care habits were registered. Caries reduction was observed in both privileged and non-privileged children. However, non-privileged children, in cohort 1983 and cohort 1998, had significantly higher DMF scores than privileged children (P < 0.01). Dental fluorosis was more often identified in privileged children than in non-privileged ones. Most of the dental factors relating to children's home based and professional care were associated with caries reduction. Caries reduction was strongly related to socioeconomic status; non-privileged children registered lower than their counterparts.

Follow-up study of dental students' esthetic perceptions of mild dental fluorosis

OBJECTIVES

Several studies have assessed people's esthetic perceptions of dental fluorosis, suggesting that concerns may be greater than believed previously. Few studies have assessed dental students' perceptions and none has done so over time. The purpose of this paper is to report on changes in dental students' esthetic perceptions of dental fluorosis and other conditions.

METHODS

Fourth-year dental students (n=45) completed questionnaires about computer-generated photographs of fluorosis and other conditions, using the same protocol as when they were entering dental students. Results were compared for each of the eight images at the individual level using paired statistical tests.

RESULTS

Although many patterns were generally consistent, there were a substantial number of differences in results over time, concerning both the mild fluorosis and non-fluorosis images. In general, students tended to score both fluorosis and non-fluorosis images more favorably as fourth-year students. When rating images from very pleased (1) to very embarrassed (10), fourth-year students rated the images significantly more favorably than they had done as first-year students for normal/control, incisal third only dental fluorosis, and a more generalized, mild fluorosis. Similarly, with a visual analog scale from satisfactory (0) to unsatisfactory (69), fourth-year students reported significantly lower (more favorable) scores than they had done as first-year students for the normal/control, diastema/no fluorosis, more involved mild fluorosis, and incisal third only mild fluorosis. There were no obvious changes in the relative levels of favorable evaluation of fluorosis vs. the other conditions.

CONCLUSIONS

Fourth-year dental students generally had more favorable esthetic perceptions of mild dental fluorosis and other conditions than they had reported as entering students.

Prevalence and trends in enamel fluorosis in the United States from the 1930s to the 1980s

BACKGROUND

The National Survey of Dental Caries in U.S. School Children: 1986-1987 conducted by the National Institute of Dental Research, or NIDR, remains the only source of national data about the prevalence of enamel fluorosis. The authors analyze these data and describe changes in the prevalence of enamel fluorosis since the 1930s, as reported by H. Trendley Dean.

METHODS

A sample of children comparable to those described in the 1930s was selected from the NIDR data set among children living in households served by public water systems during the child's first eight years of life. The type of water system (that is, natural, optimal and suboptimal) for each household had been recorded in the NIDR data set using data from the 1985 U.S. Fluoridation Census. The NIDR data set included information about the children's history of fluoride exposure obtained from parents.

RESULTS

In the 1986-1987 period, the prevalence of enamel fluorosis (ranging from very mild to severe) was 37.8 percent among children living in residences with natural fluoride (0.7 to 4.0 parts per million fluoride ions, or F-), 25.8 percent in the optimal fluoride group (0.7 to 1.2 ppm F- and 15.5 percent in the suboptimal fluoride group (< 0.7 ppm F-). The largest increase in fluorosis prevalence from the 1930s to the 1980s was in the suboptimal fluoride group (6.5 to 15.5 percent).

CONCLUSIONS AND CLINICAL IMPLICATIONS

Exposure to multiple sources of fluoride may explain the increase in enamel fluorosis from the 1930s to the 1980s. The exposure to fluoride from sources such as dietary supplements has decreased since the 1980s because of reductions in the recommended dosage, but these changes occurred too late to have an effect on the study cohort. Evidence of simultaneous use of systemic fluorides indicates the need to reinforce guidelines for the appropriate use of fluorides and promote research on measuring total fluoride exposure.

A study of some parameters in stimulated saliva from adolescents with dental fluorosis

In this study, parameters such as the flow rate, buffer capacity, sialic acid, protein and electrolyte concentrations, and amylase and peroxidase activities were analyzed in stimulated whole saliva from adolescents with dental fluorosis. From 135 adolescents (13 and 14 years-old) attending a primary and secondary school in the coastal city of Vitoria-Brazil, 72 were selected to participate in this study. The degree of fluorosis was graded using the TSIF, and was carried out by a calibrated and trained dentist. No variation in the flow rate, pH and buffer capacity, protein concentration or amylase activity was observed between the groups with dental fluorosis and the control group (fluorosis score 0). The peroxidase activity and sialic acid concentration showed some differences compared to the control. Sialic acid concentrations were reduced in the groups with dental fluorosis scores above 2. The concentration of Na was lower in adolescents with dental fluorosis, while Mg concentrations were higher in two fluorosis groups, Ca concentration was reduced in two groups with fluorosis. We conclude, that 13 and 14 year-old adolescents attending a school in the coastal city of Vitoria-Brazil showed no variations relative to some parameters and some variations in relation to others of the salivary parameters studied.

Perceptions of fluorosis in northern Cape communities

The objective of the study was to determine the perception of fluorosis in communities living in the Northern Cape Province of South Africa where there is a considerable range in fluoride levels of drinking water. The fluoride levels of the drinking water were categorised as suboptimal (0.40-0.60 ppmF), optimal (0.99-1.10 ppmF) or supra-optimal (1.70-2.70 ppmF). The teeth of 694 children aged 6, 12 and 15 years were examined. Dental fluorosis occurred among children of all ages in all areas studied. As anticipated there appears to be a direct relationship between fluoride levels in the drinking water and levels of dental fluorosis, and the severity of the condition increased with an increase in levels of fluoride in the water supplies. Children in low fluoride areas showed some form of mild fluorosis (37% very mild and 17% mild). However, 19% of this group experienced moderate or severe forms of fluorosis. In areas with optimal levels of fluoride 30% of children showed a questionable form of fluorosis and 21% mild fluorosis. Moderate or severe forms of fluorosis were recorded in 31% of children in the optimal fluoride area. The Community Fluorosis Index (CFI) scores for the sub-optimal and optimal areas were of medium public health significance and for the supra-optimal area of very high public health significance. Of concern is the high percentage of children (45%) in the supra-optimal area with severe forms of fluorosis. The awareness and concern for stains on teeth were mostly expressed by children with moderate or severe fluorosis. This study suggests that the proposed fluoride concentration (not more than 0.7 ppmF) prescribed in the Regulations on Fluoridating the Water Supplies for South Africa would minimise the risk of dental fluorosis.

Prevalence of dental fluorosis in the primary dentition

OBJECTIVES

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Dental fluorosis and caries experience in relation to three different drinking water fluoride levels in South Africa

OBJECTIVES

The purpose of this study was to determine the relationship between caries experience, degree of fluorosis and different concentrations of fluoride in the drinking water of children.

SAMPLE AND METHODS

The study included 282 children aged 10-15 years, who lived continuously since birth in three different naturally fluoridated areas (Leeu Gamka, 3.0; Kuboe 0.48 and Sanddrif 0.19 p.p.m. F), with virtually no dental care or any fluoride therapy The teeth of the children were examined for caries using the DMFT index according to th WHO criteria and for fluorosis, using Dean's criteria according to the WHO guidelines.

RESULTS

The prevalence of fluorosis (scores 2, 3, 4 and 5) among the school children was 47% in Sanddrif, 50% in Kuboes and 95% in Leeu Gamka. Almost half the children in the two low fluoride areas had no fluorosis (scores 0 and 1), whereas only 5% in Leeu Gamka had no fluorosis. Of the children in Sanddrif, 42.5% had very mild/mild (scores 2 and 3) fluorosis, 44.3% in Kuboes and 34.1% in Leeu Gamka. Except for one individual in Kuboes, severe fluorosis (score 5) was only observed in the high fluoride area in 30% of the children. According to the Bonferroni adaptation for multiple comparisons, the degree of fluorosis in Leeu Gamka differed significantly from both those of Sanddrif and Kuboes. The mean DMFT for the children in Sanddrif and Kuboe was similar (164 +/- 0.30 and 1.54 +/- 0.24, respectively) but the caries experience of Leeu Gamka (198 +/- 0.22) was significantly higher (P < 0.05) than that of both the other two areas. A strong positive correlation (P < 0.05) was found between the caries experience and the fluorosis scores of children in the high fluoride area (Leeu Gamka) but no correlation could be found in the other two areas. Significantly (P < 0.01) more children had decayed teeth in the high F area (Leeu Gamka) than in the other two areas.

CONCLUSION

The results suggest a positive association between high F levels in the drinking water and dental caries. Furthermore, a low caries experience and no difference in DMFT and fluorosis between the two low fluoride areas were found.

The prevalence of dental caries and fluorosis in Japanese communities with up to 1.4 ppm of naturally occurring fluoride

OBJECTIVES

The purpose of this study was to determine the relationship between the concentration of fluoride in drinking water and the prevalence of dental caries and fluorosis in seven Japanese communities with different concentrations of fluoride occurring naturally in the drinking water.

METHODS

A total of 1,060 10- to 12-year-old lifetime residents were examined to determine the prevalence of dental caries and fluorosis in communities with trace amounts to 1.4 ppm fluoride in the drinking water in 1987. Systemic fluorides (drops or tablets) have never been available in Japan and the market share of fluoride-containing toothpaste was 12 percent at the time of the study.

RESULTS

The prevalence of dental caries was inversely related and the prevalence of fluorosis was directly related to the concentration of fluoride in the drinking water. The mean DMFS in the communities with 0.8 to 1.4 ppm fluoride was 53.9 percent to 62.4 percent lower than that in communities with negligible amounts of fluoride. Multivariate analysis showed that water fluoride level was the strongest factor influencing DMFS scores. The prevalence of fluorosis ranged from 1.7 percent to 15.4 percent, and the increase in fluorosis with increasing fluoride exposure was limited entirely to the milder forms.

CONCLUSIONS

The findings of this study conducted in 1987 in Japan parallel those reported by Dean et al. in the early 1940s.

Prevalence and distribution pattern of enamel fluorosis in Langtang town, Nigeria

Dental fluorosis, a defect which causes white flecks or brown staining of the teeth, has been reported in some parts of the world. This study, a descriptive, cross-sectional survey was designed to determine the prevalence and distribution pattern of dental fluorosis in Langtang town, Plateau State of Nigeria between April and June 1997. Community members had recognised the discolouration of teeth as a public health problem for which solution had been sought from the near-by public health agency. A representative sample of 475 persons drawn from the 7 wards of the local government area were interviewed. Information on their age, ethnicity, occupation and source of drinking water were obtained. Intra-oral examinations were conducted to determine the status of participants' enamel using a modified version of Dean's classification of enamel mottling. Results revealed a 26.1% prevalence rate of enamel fluorosis, with 20.6% of the cases classified as mild and 5.5% as severe. While the prevalence rate was not influenced by sex and ethnicity, it was strongly associated with the source of drinking water (P < 0.05). Drinking from streams seemed to increase the likelihood of participants having dental fluorosis. A pattern of distribution with age also emerged with the highest prevalence being among the 10-19 years age group. Six cases were detected in deciduous teeth. In view of the strong indication of an environmental aetiological basis, there is need for the determination of the current levels of fluoride in water, foods beverages and other likely sources of exposure in that community.

Dental fluorosis and nutritional status of 6- to 11-year-old children living in rural areas of Paraíba, Brazil

The aim of this study was to investigate the relationship between nutritional status and dental fluorosis in areas with fluoride in the drinking water in Paraíba, Brazil. Rural villages of comparable low socio-economic status and stable water fluoride levels were selected. Lifelong residents (6-11 years old, n = 650) were examined for nutritional status (height-for-age index; WHO methods) and dental fluorosis of central incisors and first molars (TF index). The sample was divided into three groups according to fluoride levels in the drinking water: low (below 0.7 ppm F, n = 164), medium (between 0.7 and 1.0 ppm F, n = 360) and high (above 1.0 ppm F, n = 126). Dental fluorosis was observed in 30.5, 61.1 and 71.4% of the children in these F groups, respectively. The prevalence was significantly related to the water F concentrations (chi2 = 59.93, d. f. = 2, p<0.001). The severity of dental fluorosis ranged from TF 1 to 3 in the low F group and up to 7 in the others. Malnutrition prevalence was approximately 20% in all F groups, but was unrelated to dental fluorosis. The fairly high prevalence of dental fluorosis observed suggests that other factors may be operating.

Dean's fluorosis index: an assessment of examiner reliability

OBJECTIVES

This report describes the interexaminer reliability achieved using Dean's Index in a study of dental fluorosis, and shows the effect on kappa values of assigning different weights to the various components of Dean's Index.

METHODS

Three dentists conducted replicate fluorosis examinations on 202 children in Newburgh and Kingston, NY. Examiner reliability was assessed by computing percent agreement and weighted and unweighted kappa statistics.

RESULTS

Agreement on the presence or absence of fluorosis using Dean's definition of fluorosis ranged from 92 to 97 percent and the respective kappa values ranged from 0.75 to 0.94. A comparison of subject-level severity scores for Dean's Index resulted in percent agreement ranging from 79.6 percent to 86.8 percent and kappa values ranging from 0.67 to 0.76. Weighting the kappa statistics improved agreement and reduced the differences.

CONCLUSIONS

Examiners showed good to excellent agreement beyond chance in the use of the index. Subject level kappa scores were higher than tooth-level scores.

Factors affecting shear bond strength of composite resin to fluorosed human enamel

The aim of this work was to determine the effects of age, severity of fluorosis, and etching time on the shear bond strength of direct composite resin to human enamel. A total of 117 teeth, freshly extracted from patients in areas of Saudi Arabia endemic for dental fluorosis, were classified according to age (< 40 years and 40+ years) and severity of fluorosis, using the Thylstrup and Fejerskov index, TFI: TFI = 0, TFI = 1-3, and TFI = 4-6. Cylindrical composite resin specimens 5 mm in diameter and 3 mm high were bonded to the flattened midlabial enamel surfaces etched for 60 or 120 seconds and shear bond strength measured, using the Instron Universal Testing Machine at a crosshead speed of 0.5 mm/minute. Shear bond strength of the resin varied between 11.2 +/- 3.6 and 21.6 +/- 4.1 MPa. Three-way analysis of variance and Sheffé's multiple range test showed that the severity of fluorosis had no statistically significant effect on shear bond strength (p > 0.05). However, the bond was significantly stronger in teeth from patients < 40 years old than from those 40+ years old. Furthermore, at age < 40 years, shear bond strength was significantly higher in teeth etched for 120 seconds than those etched for 60 seconds (p < 0.05), but this was not the case in teeth from the older patients. In teeth with TFI = 1-3, the mode of bond failure was predominantly mixed, but at TFI = 4-6, the bond failure was mostly cohesive in enamel at all ages and etching times. It is, therefore, concluded that both age and etching time affect the shear bond strength of composite resin to fluorosed human enamel.

The prevalence and severity of enamel fluorosis in North American children

The question considered in this review is the extent to which changes in the prevalence or severity of enamel fluorosis have occurred over the last half-century. Emphasis is given to a review of those studies in which subjects are drinking water that is fluoride deficient and those in which subjects are drinking optimally fluoridated water, either adjusted or natural. Trends in fluorosis were examined using two definitions of fluorosis (definite and any signs) and three types of comparisons--comparisons of pooled estimates from all available studies that include data from different communities and time periods, comparisons of estimates from the same communities at different times, and comparisons of estimates from selected studies in the early years of fluorosis research with results of the US National Fluorosis Survey done by the National Institute of Dental Research. A clear increase in fluorosis among populations drinking community water that contains less than 0.3 ppm fluoride was found. Results of the comparisons using studies with Dean's Index pooled at different time points, comparisons in the same communities over time, and comparisons of prevalence found in selected communities before fluoride was widely available with the National Fluorosis Survey all support this conclusion. An increase in the prevalence of fluorosis in those drinking optimally fluoridated water likely has occurred as well; however, evidence for such a trend is not as clear as for fluoride deficient communities because of mixed results depending on the type of comparison. The majority of fluorosis cases continue to be mild and seem of little esthetic consequence for most of the public or dental profession. But a few cases of more severe fluorosis can be found now in some communities. Because the prevalence of fluorosis is now higher than 50 years ago, we can conclude that fluoride availability to the developing enamel during critical periods when enamel is at risk of fluorosis has increased in North American children.

The differential diagnosis of fluorosis

Following the introduction of the first fluorosis index by Dean, a series of fluorosis indexes were introduced. While they may differ in the specific way fluorosis is categorized, they all nevertheless use the same underlying diagnostic signs--originally described by Dean, Black, and McKay--that were causally linked to the development of enamel in areas with above-optimum fluoride in the drinking water. Underlying the various fluorosis indexes is the belief that specific clinical diagnostic criteria, based upon established clinical signs, can be utilized to differentiate fluorotic from nonfluorotic enamel opacities. These criteria repeatedly have been substantiated in studies in which the presence of enamel fluorosis, identified by clinical differential diagnosis, has been associated with fluoride exposure history. Further, to whatever extent nonfluorotic opacities have been misdiagnosed as fluorosis, observed estimates of association derived from analytical studies will have been underestimated.

The case for retaining the current supplementation schedule

Following ingestion of dietary fluoride, microquantities of fluoride return to the mouth in saliva, but in quantities large enough to facilitate the maintenance and reparative functions of enamel. Dietary fluoride supplements alone are unlikely to be the cause of the reported increase in fluorosis. Compliance continues to be extremely poor and few children use supplements for more than a year and a half. The amount of background fluoride resulting from dietary fluoride supplements appears to be very small. Considering the almost ubiquitous presence of fluoride dentifrice and the strong possibility of additional unintentional fluoride ingestion from many sources, the present fluorosis data is too amorphous to use as a basis for making reasonable risk/benefit evaluations. Very mild and mild fluorosis is not a serious problem for either the clinician or the patient. By altering the present recommended dosage we may deprive children from receiving a proven effective dose. One cannot make a risk/benefit decision concerning an esthetic problem without involving the patient's perception as well as the caries score. The apparent severity of the milder forms of fluorosis lessens with age and a community fluorosis index should be used only on populations who are older than 15 years.

Dental variables associated with differences in severity of fluorosis within the permanent dentition

The aim of this study was to assess the influence of age at start, duration, and completion of enamel formation, as well as of tooth-eruption age and enamel thickness on the severity of dental fluorosis within the permanent dentition. The material comprised Ugandan children (n = 219), aged 10-14 years, with 28 teeth and at least 1 tooth with fluorosis. The children were permanent residents in districts with either 0.5 mg or 2.5 mg fluoride/l in the drinking water. Fluorosis was assessed on the vestibular surfaces of all teeth using the modified Thylstrup and Fejerskov (TF) index. In order to relate fluorosis to the dental variables, the material was divided into a test group (n = 103), with fluorosis on all teeth, and a reference group (n = 116), with fluorosis on up to 27 teeth. The reference group was used to confirm or refute the findings in the test group. Paired comparisons showed significantly higher median TF scores for the late than for the early mineralizing and erupting teeth. In multiple regression analyses, the age at start, duration, and completion of enamel formation as well as tooth eruption was significantly related to the severity of fluorosis after controlling for enamel thickness (P < 0.05, n = 14). The effect (R2change) of the dental variables on the variation in severity of fluorosis within the dentition was in decreasing order: the duration of enamel formation, age at completion of enamel formation, tooth-eruption age, and the start of enamel formation.

Weaning food and magadi associated with dental fluorosis in Northern Tanzania

A cross-sectional study of 143 children aged 10-14 years was carried out to identify factors associated with the severity of dental fluorosis in 2 areas (Moshi/Kibosho: n = 63/80) with fluoride (F) concentrations < 0.4 mg F/L in the drinking water. Dental fluorosis was recorded under field conditions using the Thylstrup and Fejerskov index (TFI). The score on tooth 21 was used to indicate the severity. The prevalence of dental fluorosis in Moshi at TFI score > or =1 was 60% and at TFI score > or =5 it was 10%. The corresponding values in Kibosho were 100% and 34%, respectively. Background variables pertained primarily to the child's first 6 years of life. In Moshi and Kibosho, 65% and 97% of children, respectively, used magadi, a fluoride-containing food tenderizer. In Moshi, the risk of having TFI score > or =2 was significantly higher among users of magadi (odds ratio (OR) = 5). Kiborou, a traditional homemade weaning food (porridge) cooked with magadi, was used only in Kibosho. Users of kiborou (36%) were at significantly higher risk (OR = 3) of developing fluorosis at severity TFI > or =4 than the users of lishe, another type of weaning food. All children in Moshi and 64% in Kibosho used lishe, which is cooked without magadi. Magadi and kiborou were significant risk indicators. Thus, it seems that the unexpectedly high prevalence of dental fluorosis and the observed differences in fluorosis prevalence and severity may be partly explained by F exposure from magadi.

Effect of fluorosis on etching of human enamel

To investigate the effect of fluorosis on the pattern and depth of etch of human enamel, 420 enamel specimens classified according to the Thylstrup and Fejerskov index (TFI) were etched with 37% phosphoric acid for varying times. The mean depths of etch for mildly fluorosed enamel (TFI = 1-3) were generally dependent on etching time (r = 0.55-0.76), and were not significantly different from the depth obtained for non-fluorosed (TFI = 0) specimens. The enamel specimens with more severe fluorosis (TF = 4) required longer etching time which showed little correlation with the mean depth of etch (r = 0.15-0.16). Furthermore, the etched specimens showed typical enamel etching patterns, independent of the severity of fluorosis. When the specimens with TFI = 4 were etched for 45 s, the subsurface organic network was evident, but this disappeared and typical etching patterns could be seen again when etching time was increased to 75-90 s. It is therefore concluded that the diagnosis of the severity of fluorosis must first be made whenever etching of fluorosed enamel is contemplated.

Prevalence and severity of dental fluorosis in Al-Qaseem province--Kingdom of Saudi Arabia

OBJECTIVE

To assess the oral health status, especially prevalence and severity of dental fluorosis among an urban and rural population of Al-Qaseem province.

DESIGN

World Health Organization (WHO) oral health form was used to survey the population.

SETTING

Subjects were surveyed from Urban and rural schools, Government and non-governmental organizations, administrative and training institutes of Buraida city and villages of Ain Al-Juwa and Al-Asiah.

SUBJECTS

Eight hundred male subjects were surveyed in 12, 15, 35-44 and > 65 years age groups. Four hundred urban and four hundred rural subjects were examined. One hundred in each group.

RESULTS

It was found that fluorosis is more prevalent in rural than urban population. 24-67 percent of 12, 15, 34-44 and > 65 years were with dental fluorosis both in urban and rural areas. 12.5 percent of the population examined were with moderate to severe dental fluorosis. Eight percent of the urban and 16.3% of rural population were with moderate to severe dental fluorosis.

CONCLUSIONS AND RECOMMENDATIONS

Rural population have more prevalent and severe dental fluorosis as compared to urban population of Al-Qaseem province. There is a need of preventive oral health programs with community education on their diet and water consumption. There is a need to improve water supplies and defluoridation of water sources in affected areas. Multiple sources of fluoride should be analysed and prevented. From treatment need point of view, there is also a need to meet the increased demand of cosmetic restorations for aesthetic units of dentition.

Effect of fluorosis on shear bond strength of glass ionomer-based restorative materials to dentin

STATEMENT OF PROBLEM

Several studies have investigated the adhesion of glass ionomer-based restorative materials to nonfluorotic teeth, but there appears to be no information on the bond strength of these restorative materials to dentin in fluorotic teeth.

PURPOSE

This study investigated the effect of dental fluorosis on the bond strength of Ketac-fil conventional glass ionomer cement, Vitremer resin-modified glass ionomer cement, and Dyract polyacid modified resin to dentin.

MATERIAL AND METHODS

Ninety posterior teeth were classified according to the severity of fluorosis, by using the Thylstrup and Fejerskov index, TFI. The teeth were divided into 3 equal groups (TFI = 0,TFI = 1-3, TFI = 4+) of 30 teeth, which were again divided into 3 equal subgroups for testing each of the3 restorative materials. Occlusal surfaces of mounted teeth were ground flat to expose dentin. Cylindrical specimens (4 mm diameter and 4 mm high) of the restorative materials were bonded to the middle of the cleaned exposed dentin surfaces, according to the manufacturers' instructions. After storing the specimens in 100% humidity at 37 degrees C for 24 hours, shear bond strengths of the restorative materials were measured with an Instron testing machine at crosshead speed of 0.5 mm/min.

RESULTS

Two-way analysis of variance and Tukey-B test revealed that Dyract had significantly higher shear bond strength to dentin than Ketac-fil or Vitremer cements, regardless of severity of fluorosis (P <.05). Furthermore, there was an inverse relationship between shear bond strength and the severity of fluorosis for each of the restorative materials. Cohesive mode of failure was most prevalent in nonfluorotic teeth (TFI = 0), especially with Ketac-fil cement, whereas Dyract cement had the greatest propensity for adhesive failure.

CONCLUSION

Fluorosis reduces the shear bond strength of glass ionomer-based restorative materials to dentin.

Investigation of the possible associations between fluorosis, fluoride exposure, and childhood behavior problems

PURPOSE

This study investigated the potential association between fluoride exposure and behavior problems in children, as well as the prevalence of and risk factors for fluorosis.

METHODS

Children between the ages of 7 and 1 years (N = 197) were included in the study and were examined for dental fluorosis using the Modified Dean's Index. Parents of subjects completed and returned three questionnaires which investigated their children's history of exposures to fluoride, social and medical backgrounds, and behavior using the Child Behavior Checklist (CBCL).

RESULTS

Sixty-nine percent of the study participants demonstrated fluorosis with very mild fluorosis being the most common (39%), while 13% demonstrated moderate to severe fluorosis. Using a summation of the Modified Dean's index (Sum of 8), we divided the children into high fluorosis (HF) and low fluorosis (LF) groups. These groups were compared to each other with respect to fluoride exposures and behavior.

CONCLUSION

Although there was no association between the fluoride exposures in aggregate and fluorosis, there was a significant association between supplemental fluoride exposure from ages 0-3 years and fluorosis. There was no association between behavior problems and dental fluorosis in this population.