Another ecologic study attempting to infer associations with very weak correlations. Would nonconsumption of food be associated with a lower prevalence of elevated dental caries?
Sanders AE, Slade GD. Blood Lead Levels and Dental Caries in U.S. Children Who Do Not Drink Tap Water. American journal of preventive medicine. 2017 Nov 18. pii: S0749-3797(17)30495-6. doi: 10.1016/j.amepre.2017.09.004.
INTRODUCTION: This study’s purpose is to determine whether nonconsumption of tap water is associated with lower prevalence of elevated blood lead levels and higher prevalence of dental caries in children and adolescents.
METHODS: Cross-sectional data from the National Health and Nutrition Examination Survey 2005-2014 recorded drinking water source (n=15,604) and blood lead levels (n=12,373) for participants aged 2-19 years, and dental caries experience for the 2011-2014 subset (n=5,677). The threshold for elevated blood lead level was ≥3 μg/dL. A binary outcome indicated presence or absence of dental caries experience. Multivariable generalized linear models estimated adjusted prevalence ratios with 95% confidence limits.
RESULTS: In analysis conducted in 2017, 15% of children and adolescents did not drink tap water, 3% had elevated blood lead levels ≥3 μg/dL, and 50% had dental caries experience. Children and adolescents who did not drink water were less likely than tap water drinkers to have an elevated blood lead level (adjusted prevalence ratios=0.62, 95% confidence limits=0.42, 0.90). Nonconsumers of tap water were more likely to have dental caries (adjusted prevalence ratios=1.13, 95% confidence limits=1.03, 1.23). Results persisted after adjustment for other covariates and using a higher threshold for elevated blood lead level.
CONCLUSIONS: In this nationally representative U.S. survey, children and adolescents who did not drink tap water had lower prevalence of elevated blood lead levels and higher prevalence of dental caries than those who drank tap water.
Adding fluoride to drinking water is the sacred cow for advocates within the dental community (e.g. here). Much has been written on this topic and many articles can be found on this blog and other sites. The presumption of safety was imposed and institutionalized early on. But evidence is not neutral. The assumptions of the interpreter determine what conclusions are reached based on the evidence. The historical presumption of safety (it is safe until proven that it is not) has result the same conclusion of safety by every government or association panel evaluation of fluoridation. But evidence-based hazards and risks have been completely ignored or downplayed from the beginning of the practice. Indeed, organizations simply repeat the same song typically endorsing each others endorsement. The absence of dead bodies in the street or repetitive results from ecological studies interpreted using particular statistical tests is simply not sufficient justification for continuing the practice. But it continues nevertheless…
C Carstairs Debating Water Fluoridation Before Dr. Strangelove. American Journal of Public Health. 2015;105:1559–1569. doi:10.2105/AJPH.2015.302660.
In the 1930s, scientists learned that small amounts of fluoride naturally occurring in water could protect teeth from decay, and the idea of artificially adding fluoride to public water supplies to achieve the same effect arose. In the 1940s and early 1950s, a number of studies were completed to determine whether fluoride could have harmful effects. The research suggested that the possibility of harm was small. In the early 1950s, Canadian and US medical, dental, and public health bodies all endorsed water fluoridation. I argue in this article that some early concerns about the toxicity of fluoride were put aside as evidence regarding the effectiveness and safety of water fluoridation mounted and as the opposition was taken over by people with little standing in the scientific, medical, and dental communities. The sense of optimism that infused postwar science and the desire of dentists to have a magic bullet that could wipe out tooth decay also affected the scientific debate.
Rizzolo D, Bowser J. Update on pediatric oral healthcare.JAAPA. 2016 Aug;29(8):52-3. doi: 10.1097/01.JAA.0000484312.96684.d7.
As part of the patient-centered medical home, clinicians are being asked to apply fluoride varnish and perform oral examinations in children. This article reviews the latest national recommendations for fluoride varnish use to prevent dental caries.
Hendaus MA, Jama HA, Siddiqui FJ, Elsiddig SA, Alhammadi AH. Parental preference for fluoride varnish: a new concept in a rapidly developing nation. Patient Prefer Adherence. 2016 Jul 13;10:1227-33. doi: 10.2147/PPA.S109269.
OBJECTIVE: The objective of this study was to investigate parental preference for fluoride varnish in a country where the average percentage of dental caries in young children is up to ~73%. Consequently, the aim of this study, despite being a pilot, was to create a nationwide project in the State of Qatar to promote oral health in children.
METHODS: A cross-sectional perspective study was conducted at Hamad Medical Corporation in Qatar. Parents of children aged ≤5 years were offered an interview survey. A total of 200 questionnaires were completed (response rate =100%). The study was conducted between December 1, 2014 and March 30, 2015, and included all children aged >1 year and 90% of families were aware that dental health affects the health of the whole body. The study showed that ~70% of parents were not aware of the existence of fluoride varnish, but would allow a health provider to apply fluoride varnish. Furthermore, ~80% of parents would not stop brushing their child’s teeth and would not skip dentist appointments if varnish was to be applied. Approximately 40% of parents conveyed some concerns regarding the safety of fluoride varnish, despite being considered as a new concept. The main concern was that the child might swallow some of the fluoride. Another important concern expressed by parents was the availability of the fluoride varnish in all clinics.
CONCLUSION: The robust positive attitude of parents in this sample suggests that introducing fluoride varnish is feasible and acceptable in our community. Actions to augment fluoride varnish acceptability in the developing world, such as focusing on safety, could be important in the disseminated implementation of fluoride varnish.
Martinez-Mier EA, Shone DB, Buckley CM, Ando M, Lippert F, Soto-Rojas AE. Relationship between enamel fluorosis severity and fluoride content. Journal of Dentistry. 2016 Jan 22. pii: S0300-5712(16)30007-0. doi: 10.1016/j.jdent.2016.01.007.
OBJECTIVES: Enamel fluorosis is a hypomineralization caused by chronic exposure to high levels of fluoride during tooth development. Previous research on the relationship between enamel fluoride content and fluorosis severity has been equivocal. The current study aimed at comparing visually and histologically assessed fluorosis severity with enamel fluoride content.
METHODS: Extracted teeth (n=112) were visually examined using the Thylstrup and Fejerskov Index for fluorosis. Eruption status of each tooth was noted. Teeth were cut into 100μm slices to assess histological changes with polarized light microscopy. Teeth were categorized as sound, mild, moderate, or severe fluorosis, visually and histologically. They were cut into squares (2×2mm) for the determination of fluoride content (microbiopsy) at depths of 30, 60 and 90μm from the external surface.
RESULTS: Erupted teeth with severe fluorosis had significantly greater mean fluoride content at 30, 60 and 90μm than sound teeth. Unerupted teeth with mild, moderate and severe fluorosis had significantly greater mean fluoride content than sound teeth at 30μm; unerupted teeth with mild and severe fluorosis had significantly greater mean fluoride content than sound teeth at 60μm, while only unerupted teeth severe fluorosis had significantly greater mean fluoride content than sound teeth at 90μm.
CONCLUSIONS: Both erupted and unerupted severely fluorosed teeth presented higher mean enamel fluoride content than sound teeth.
CLINICAL SIGNIFICANCE: Data on fluoride content in enamel will further our understanding of its biological characteristics which play a role in the management of hard tissue diseases and conditions.
Strittholt CA, McMillan DA, He T, Baker RA, Barker ML. A Randomized Clinical Study to Assess Ingestion of Dentifrice by Children. Regulatory toxicology and pharmacology 2015 Dec 22. pii: S0273-2300(15)30143-4. doi: 10.1016/j.yrtph.2015.12.008.
This study investigated whether there was a difference in amounts of dentifrice ingested by children based on age using pea-sized instructions. The study had a randomized, single-blinded, 3-period, crossover design modelled after Barnhart et al. (1974) with one regular-flavored and two specially-flavored dentifrices used ad libitum. Subjects were enrolled in three groups: 2-4, 5-7, and 8-12 years. They were instructed to brush at home as they would normally with each dentifrice for 3 weeks (9 weeks total). On weekly study-site visits, subjects brushed with the assigned dentifrice containing a lithium marker to measure the amount of dentifrice ingested and used. Averaging across dentifrices, amounts ingested were: 0.205g (2-4yr), 0.125g (5-7yr) and 0.135g (8-12yr), demonstrating 2-4 year-olds ingested significantly more than older children (p≤0.002). Averaging across dentifrices, amounts used were: 0.524g (2-4yr), 0.741g (5-7yr) and 0.978g (8-12yr) suggesting an age-related effect (p<0.01). Findings also showed that ingestion amount for specially-flavored dentifrices may increase relative to regular-flavored dentifrice for children 2-7 years-old. This research demonstrated that dentifrice ingestion amount decreased significantly with age while usage amount increased with age. Importantly, ingestion and usage levels in younger children reflect “pea-sized” direction and were numerically lower than historical levels reported prior to this direction.
Fluorosis will occur even in a small portion of an exposed population even at 0.7 mg/L in drinking water. It’s easy to say that fluorosis is not a problem at this level when it’s not your teeth (or children) being adversely affected.
Khairnar MR, Dodamani AS, Jadhav HC, Naik RG, Deshmukh MA. Mitigation of Fluorosis – A Review. Journal of Clinical and Diagnostic Research 2015 Jun;9(6):ZE05-9. doi: 10.7860/JCDR/2015/13261.6085.
Fluoride is required for normal development and growth of the body. It is found in plentiful quantity in environment and fluoride content in drinking water is largest contributor to the daily fluoride intake. The behaviour of fluoride ions in the human organism can be regarded as that of “double-edged sword”. Fluoride is beneficial in small amounts but toxic in large amounts. Excessive consumption of fluorides in various forms leads to development of fluorosis. Fluorosis is major health problem in 24 countries, including India, which lies in the geographical fluoride belt. Various technologies are being used to remove fluoride from water but still the problem has not been rooted out. The purpose of this paper is to review the available treatment modalities for fluorosis, available technologies for fluoride removal from water and ongoing fluorosis mitigation programs based on literature survey. Medline was the primary database used in the literature search.