FLUOROSIS

INDEX• INTRODUCTION • EPIDEMIOLOGY• CHRONIC FLUORIDE TOXICITY• DENTAL FLUOROSIS• ACUTE FLUORIDE TOXICITY• INDICES TO MEASURE DENTAL FLUOROSIS• THE COMMONLY RECOGANISED EFFECT OF FLUORIDE INGESION THROUGH FLUORIDATED WATER AT VARIOUS

LEVELS• EFFECT OF FLUORIDE THROUGH VARIOUS MEDIA• FLUORIDE ANALYSIS METHODS• SOURCES OF FLUORIDE FOR ADULTS• SOURCES OF FLUORIDE FOR INFANTS• FLUORIDE HOMEOSTASIS• FLUORIDE IN SALIVA• RECOMMENDED SCHEDULE FOR USE OF FLUORIDE DENTIFRICE IN VERY YOUNG CHILDREN• PREVENTION OF DENTAL FLUOROSIS• TREATMENT OF DENTAL FLUOROSIS• PROGNOSIS

INTRODUCTION

• Fluoride is a double edged sword. Fluoride at optimal level not only decreases the incidence of dental carries but also necessary for maintaining the integrity of oral tissues and at the same time at higher levels that too if taken excess during developmental stages can cause adverse effects like dental fluorosis and skeletalfluorosis . The range of fluoride concentration normally recommended is 0.8-1.2ppm. The fluoride concentration more than 1ppm may result in some form of toxicity like fluorosis. Chronic ingestion of excess fluoride during developmental stages only over a long period of time causes fluorosis.

• It is well documented that fluoride can have both beneficial and detrimental effects on the dentition ever since Mc Kay and G.V. Black in 1916 published the effect of fluoride on dentition. The beneficial effects of fluoride on dental caries are due primarily to the topical effect of fluoride after the teeth have erupted in the oral cavity. In contrast, detrimental effects are due to systemic absorption during tooth development resulting in dental fluorosis.

EPIDEMIOLOGY

• Credit for the identification of the scientific basis for the fluoride in preventing and treating dental caries is largely attributed to the work of two American dentists - Dr. Fredrick McKay and an US public health officer H. Trendley Dean. It was Dean, 1934, who developed a classification for fluorosis, which is still widely used, based on his interpretation of clinical appearance. Dean and McKay suggested that optimum level of water fluoride should be below 0.9 - 1.0 PPM.

• In 1901 Dr Fredrik Mackay of Colorado,USA accidently discovered that many of his patients had permanent stains on their teeth .He called them as COLORADO STAIN and published in Dental cosmos. When Mackay enquired with local people, They simply referred them as Colorado brown stain and they were formed most commonly among the local residents who lived there for a long time. They later referred them as mottled enamel in 1916.later he noticed that mottled was found among people who were born there, regardless of richness and poverty. Thus he ruled out that diet has no etiologic factor. Through out his studies he experienced that dental carries experience was very low among the mottled teeth. Finally he concluded that fluoride in the domestic water is the primary cause of human mottled enamel. The publication of this information brought to successful and fruitful conclusion for,mckay’s search for the cause of mottled enamel which began in Colorado springs in1901 and lasted for almost 40 years.

Dean conducted a survey among 7257 children of the age group of 12to 14 years from 21 cities of 4 states to find the possible association between increasing fluoride concentration in drinking water and degree of dental fluorosis-DEANS 21 CITY STUDY.

• Results As fluoride concentration increased from 0ppm there is decrease in carries experience. Maximum reduction of carries occurred at 1 ppm at this concentration fluoride caused only sporadic mildest form of dental fluorosis of no practical aesthetic significance. If fluoride level increases more than 1ppm there is no further reduction of dental carries but there could be chances of appearance of fluorosis.

• In India, fluorosis was identified in 1937 in Nellore of Andhra Pradesh by Shortt et al Geological crust of India, especially South India, has fluoride rich bearing minerals which can contaminate underground aquifers. Nearly 73% of Tamil Nadu is hard rock crust. In Tamil Nadu, Madurai is a known endemic fluorosis area and has fluoride level in drinking water of about 1.5 - 5.0ppm.

CHRONIC FLUORIDE TOXICITY• Chronic fluoride toxicity result from long term ingestion of small

amount of fluoride.• The effect of chronic fluoride toxicity on enamel is DENTAL FLUROSIS.• Fluorosis is an endemic disease in geographic areas where the content

of fluoride ion in the drinking water exceeds 2ppm.• Clinical features of dental fluorosis is extremely variable.• ENAMEL FLUROSIS-It is a developmental phenomenon due to excessive

fluoride ingestion during amelogenesis.Once the crown of the teeth are formed no further fluorosis can be induced by additional intake of fluoride or by post eruptive topical application of fluoride.

• Fluorosis occur symmetrically within the dental arches. The premolars is usually effected, followed by 2nd molar ,maxillary incissors,canine,first molar and mandibular incisors.

DENTAL FLUOROSIS• Dental flurosis is a hypoplasia or hypomineralisation of tooth or dentine ,produced

by chronic ingesion of excessive amounts of fluride during the period when teeth are developing.

• Dental flurosis is characterised by lusterless,opaque,white patches in the enamel which may become mottled,stained or pitted.The mottled areas may become stained yallow or brown.

• The major cause of dental flurosis is consumption of water,containing high levels of fluride by infants and children during the first 6 years of life.

• 0 to 6 year is the widow period for flurosis.• Although both primary and permanent teeth may be effected by flurosis,It is more

in permenent teeth than in primary teeth.• This discripancy may be due to the fact that much of the mineralisation of primary

teeth occur before birth and placenta serves as a barrier to the transfer of high concentration of plasma fluoride from apregnent mother to her developing featous,Thus controlling to a certain extend the delivery of fluoride to the developing primary dentition.

• The earliest manifestation of dental fluorosis is an increase in enamel porosity along the striae of Retzius. Clinically, the porosity in the subsurface of enamel reflects as opacity of the enamel. With an increased exposure to fluoride during tooth formation, the enamel exhibits an increased porosity in the tooth surface along the entire tooth surface. Very severely hypo mineralized enamel will be very fragile and hence as soon as they erupt into oral cavity they undergo surface damage as a result of mastication, attrition and abrasion. The definite evidence that fluoride can induce dental fluorosis by affecting the enamel maturation was given by Richards et al.

• Recommended optimum level of fluoride for drinking water is 0.7-1.2 PPM.

• Average daily intake of fluoride from all sources for adults is 2-2.2mg and in case of children it is 1.2mg.

ACUTE FLUORIDE TOXICITY• Acute fluoride toxicity results from rapid ingesion of fluoride at one time.• The speed and severity of the response are dependent on the amount of

fluoride ingested and weight and age of individual• Initial symptoms of fluoride toxicity includes-• Gastrological signs-hypersalivation,nausea,vomitting,diarrhoea,

abdominalpain,mucosal injury.• Neurological signs-headache,tremors,muscular spasam tetanic

contractions,seizures,muscle weekness.• Electrolytic abnormalities-

hypocaliemia,hypomagnesia,hypoglycemia,hypercaliemia.• Acute fluride toxicity can result when dose of fluride intake starts from certain

level of fluride that is 32-64mg/kg body weight ie approximately 2.5-5 gm of fluride in case of children and 5-10gm one single retained dose in case of adults

• The safety tolerated dose is 8-16per kg body weight

• Causes• The most common type of exposure is ingesion of

product that contain fluoride• Toothpaste contain 1mg/gm of fluoride as

sodiummonoflurophosphate.This fluride formulations has low solubility and is generally non toxic.

• The toxic effect following large ingesion of the following products usually are limitted to GI discomfort-Tooth paste ,Oral hygiene products

• Emergency care provide cardiac monitoring

• Perform gastric aspiration and lavage• Gastric aspiration and lavage are most effective

when instituted with in 1hr of ingesion• Administer milk,calciumcarbonate,aluminium

and magnesium based antacids to bind fluride• Correct calcium defeciencies with iv

calciumchloride.

INDICES TO MEASURE DAENTAL FLUOROSIS

• Indices to measure dental fluorosis are-• Deans fluorosis index –Dean• Tooth surface index of fluorosis• Community fluorosis index• Jackson’s simple fluorosis index

Deans fluorosis index• Normal-0• Enamel represents usually translucent type of structure• The surface appears smooth glossy and usually of a pale creamy white color.• Diagnosis of the mildest form of fluorosis is not warranted and a classification of normal is not justified.• Questionable-1• Enamel discloses slight abrrations from translucency of normal enamel ranging from a few white flecks

to occasional white spots• Very mild-2 • Small opaque paper white areas are scattered irregularly over the tooth ,but not involving as much as

approximately 25% of the tooth surface• Frequently involved in this classification are teeth showing no more than about 1-2 mm of opacity at

the tip of the summit of the cusps of the bicuspids/second molars.• Mild-3 • White opaque areas in enamel of the teeth are more extensive, but do not involve as much as 50% of

the tooth.• Moderate-4• All 5 enamel surfaces of the teeth are effected and surfaces subject to attrition show wear. The brown

stain is frequently a disfiguring feature.• Severe-5 • All enamel surfaces are effected and hypoplasia is so marked that the general form of the tooth may be

affected.• The major diagnosing feature of this classification is discrete or confluent pitting.• Brown stains are wide spread and teeth often present a corroded like appearance.

THYLSTRUP AND FEJERSKOV INDEX(1978)

• 0 – Normal translucency of the glossy creamy white enamel remains after wiping and drying of the surface

• 1 – Thin white lines are seen across the tooth surface• 2 – Opaque white lines are more pronounced and

frequently merge to form small cloudy areas scattered over the whole surface of the tooth

• 3 – Merging of white lines occurs, and cloudy areas of opacity occurs spread over many parts of the surface. In between the cloudy areas, white lines also can be seen

• 4 – The entire surface exhibits a marked opacity or appears chalky white

• 5 – The entire surface is opaque and there are round pits

• 6 – The small pits frequently merge in the opaque enamel and forms bands

• 7 – There is loss of outer surface of enamel in irregular areas and less than half the surface is involved

• 8 – The loss of outer most enamel surface is more than half the enamel

• 9 – The loss of major part of the outer enamel results in change of anatomical shape of the tooth

DENTAL FLUOROSIS

COMMUNITY FLUOROSIS INDEX

• Fci=∑(n×w)– N– n-Number of children in each category– w-weighing for each category– N-Total population

Public health significance of different fluoride levels using CFI

Fluoride Level• 0.0-0.4• 0.4-0.6• 0.6-1.0• 1.0-2.0• 2.0-3.0• 3.0-4.0

Public health significance• Negative• Border line• Slight• Medium• Marked• Very marked

JACKSON SIMPLE FLUOROSIS INDEX(1974)

• Type A• • Type B• Type C• Type E

• Type F

• White areas less than 2 mm in diameter

• White areas of 2 or greater than 2 mm in diameter

• Coloured brown areas less than 2 mm in diameter

• Horizontal white lines irrespective of being any white non linear areas.

• Coloured brown or white areas or lines associated with pits or hypo plastic areas.

Fluoride analysis methods

• Fluoride analysis methods are-• Ion chromatography• Spectrophotmetric method• Aluminium monofluoride molecular

absorption spectrometry• Photon induced x ray emission• Electron probe microanalysis• X ray induced photoelectron spectroscopy

Sources of fluoride for adults

• The greater part of the fluoride intake in man originates from food and water ingested each day

• Fluoride is also derived from certain plants, marine animals, and even from atmosphere(coal smoke, volcanic emission)

• It is estimated that most of fluoride in water is due to its solvent action on rocks and minerals

• The concentration of fluoride in ground water depends on amount of fluoride containing minerals present, temperature and ph of water

• The most commonly available solid fluoride in nature is in the form of compounds like flurapetite,cryolite or fluorspar

• Earth’s crust contain 880ppm of fluoride, rocks contain about 300-700ppm of fluoride and this is leached out to ground water and surface water.

• Deep well water contain high level of fluoride • Sea water contain about 0.8-1.4ppm of fluoride

Fluorides in food

• Fish contain good amount of fluoride(19ppm)• Tea leaves contain about 97ppm of fluoride• Potato's contain 6.5ppm of fluoride• Certain plants such as taro,yans,and carsana

which constitute the staple diet of people in many tropical areas particularly in south America and in the pacific have been found to contain relatively high fluoride level.

Sources of fluoride for infants

• Fluoride concentration of human milk ranges from 6-12mg per ml

• The fluoride intake in infants is mainly determined by the fluoride concentration of water used.

Fluoride homeostasis

• The dynamic equilibrium between fluoride uptake and fluoride excretion.

• It depends on absorption, deposition in different structures of body, and excretion of fluoride

ABSORPTION OF FLUORIDE

• The main rout of absorption is via gastrointestinal tract

• Maximum plasma concentration of 0.15-0.25ppm reaches with in 60min.

• Depending on the physical and chemical properties of compound and its solubility, varying amount of ingested fluoride dose will be absorbed and reaches systemic circulation

• Stomach is the major site of absorption

FLUORIDE IN BLOOD

• The maximum plasma fluoride concentration is found with in 30-60min of ingestion of soluble fluoride.

• Fluoride exist both in ionic and bound form, where bound form is present in large quantity

• When water contains 1.2ppm of fluoride, the ionic fluoride in plasma ranges from0.25-2ppm

FLUORIDE IN SALIVA• Fluoride concentration in human saliva is less

than those found in plasma ranging from 0.01-0.05ppm

• Unstimulated saliva contain more fluoride than stimulated saliva

• Sodium fluoride, stannous fluoride and sodium monofluorophosphate all increase salivary fluoride level more than the aluminium fluoride or calcium fluoride

RECOMMENDED SCHEDULE FOR USE OF FLUORIDE DENTIFRICE IN VERY YOUNG

CHILDREN

• Below 4 years

• 4-6 years

• 6-10 years

• Above 10 years

• Fluoride tooth paste is not recommended

• Brushing once daily with fluoride toothpaste and twice without paste

• Brushing twice daily with fluoride paste and once without paste

• Brushing thrice daily with fluoride tooth paste

Fluorosis is a cosmetic problem and not a dental disease. Teeth are strong and healthy, but the spots and stains left by fluorosis are permanent and may darken over time. Dental fluorosis can be cosmetically treated by a dentist by micro abrasion or tooth bleaching. Dental or Enamel fluorosis occurs only while the teeth are still developing under the gums, before their eruption.

Parents should take the necessary measures for preventing dental fluorosis on their children teeth : Powdered or liquid concentrate infant formula should be mixed with water that is fluoride-free or contains low levels of fluoride, Do not use fluoride toothpaste until the child is two years old unless advised to do so by a dentist, For children age two and older, place only a pea-sized amount of fluoride toothpaste on the toothbrush at each brushing, Avoid toothpastes with flavors that may encourage swallowing, An adult should supervise the use of fluoride-containing dental products by children younger than six years old, and check that they do not swallow it.

PREVENTING DENTAL FLUOROSIS

Defluoridation of water using Nalgonda Technique

Its a simple and economical method of removing fluoride from drinking water. Nalgonda technique involves the addition of aluminium salts, lime and bleaching powder followed by rapid mixing, flocculation, sedimentation ,filtration and disinfection.

Procedure•Rapid MixingThorough mixing of alkali, aluminium salts and bleaching powder with water. The chemicals are added just when the water enters the system.•Flocculation•Sedimentation permits settled floc loaded with fluoride, turbidity , bacteria and other impurities to be deposited and thus reduces concentration of solid that must be removed by filters•Filtration•Disinfection

• The damage that dental fluorosis causes to the teeth enamel is permanent and not reversible. Dental fluorosis treatment is targeting in hiding the discoloration of the teeth. Treatment options depend on the severity of dental fluorosis. Tooth whitening - only for mild fluorosis cases. The whitening is achieved by the abrasion of the outer layer of the enamel in order to remove surface stains. In cases of severe dental fluorosis the tooth enamel usually becomes porous, and tooth whitening methods are not recommended as treatment. Dental fluorosis treatment for severe cases of fluorosis requires covering the affected teeth with restorations, such as : Composite bonding. After etching the enamel, a composite resin (with a colour matching the other teeth) is "glued" on to the exterior of the tooth. Porcelain veneers. Made out of porcelain, veneers form a ceramic shell over the surface of the tooth, covering the stains and discoloration caused by the dental fluorosis. Tooth bonding and porcelain veneers are relatively expensive dental fluorosis treatments but they can provide excellent cosmetic results.

DENTAL FLUOROSIS TREATMENT

1. BLEACHING:

Bleaching can remove only extrinsic stains but does not change the white chalky appearance.

Two types - 1. Matrix (Night Guard) home bleaching.

2. In practice - vital bleaching

Materials used:

1. Carbamide peroxide

2. Superoxol

PRE OPERATIVE CASE

ETCHING FOLLOWED BLEACHING WITH MC INNES SOLUTION

Prognosis

• Teeth affected by fluorosis are not diseased. Fluorosis will not result in cavities or other dental problems. Concerns about appearance can be addressed with whitening to remove surface stains and veneers or other procedures to cover the discoloration.

SKELETAL FLUOROSIS

• Skeletal fluorosis occurs from ingestion of very high amounts of fluorides for long period of time.

• In India, the disease was first reported by Vishwananthan in 1935

• At water fluoride levels above 8ppm, skeletal fluorosis may develop

Excess fluoride intake also interferes with normal bone developmentThe early stage of skeletal fluorosis, is characterized by joint pain, sensations of burning, pricking, and tingling in the limbs, muscle weakness, chronic fatigue, and reduced appetite. In the more advanced stages, pains in the bones become constant and some of the ligaments begin to calcify and bony outgrowth may occur. In the most advanced stage, the extremities become weak and moving the joints is difficult. The vertebrae partially fuse together, crippling the patient. Bones also become brittle.

Skeletal fluorosis

conclusion

• Fluorosis is a cosmetic problem not a dental disease

• Parents should take necessary measures for preventing dental fluorosis on their childrens teeth

• When used appropriately fluoride is asafe and effective agent that can be used to prevent and control dental carries

• Fluoride is needed regularly through out life to protect tooth against tooth decay

references

• Essentials of preventive and community dentistry_soben peter

• Parks text book of preventive and social medicine-k.park

• From net