Fluoride PDF

25.10.2024 FLUORIDE What is Fluoride?  Fluoride is the most electronegative and most...

25.10.2024 FLUORIDE What is Fluoride?  Fluoride is the most electronegative and most reactive element  It reacts with all the elements  It is not found free in the nature  Very difficult to isolate  It cannot be stored in glass and silicon environments as it forms compounds with glass and silicon Assoc. Prof. Dr. Belen ŞİRİNOĞLU ÇAPAN What is Fluoride? Fluoride  It is found as fluorine salts (fluorides) by forming compounds in  Fluoride is most common in nature in: nature  Volcanic lands  It binds to inorganic structures mostly in ionic form:  Groundwater outlet points  Located in areas close to sea water  Fluorite CaF2  Fluoride is found in water, soil, rocks, atmosphere, food and drinks, plants and animals, and living tissues. However, it is mostly found in tea, tobacco and fish.  Kriolite 1  25.10.2024 Fluoride Fluoride  Fluoride in industry  ppm (part per million = units per million)  1 ppm = 1 mg/l = 1 mg/kg  Used in the melting of metal alloys  In sea water: 0.8-1.4 ppm  Used as an electrolyte in the synthesis of aluminum  Lake Water / artesian water: 0.5-95 ppm  In the production of teflon and high hardness plastic  Most fluoride intake in humans is through drinking water.  Sodium fluoride is a strong pesticide and insecticide  Fluoride existing in the earth's crust can pass to the atmosphere and plants; afterwards, it spreads again to the soil, water and atmosphere in the form of rain, snow, fog, plant and food waste. Fluoride Fluoride Metabolism  75-90% of oral fluoride is absorbed from the GI system, especially from the  Fluoride in industry stomach, and passes into the blood.  Fluoride absorption is in the form of passive diffusion.  HF (Hydrofluoric acid) is used to cauterize many  The highest concentration of plasma usually occurs within 20-60 minutes. glass in industry, including light bulb production The remaining fluoride is excreted with urine and feces.  CaF2 (calcium fluoride) is used to make lenses  High amounts of calcium or cations [(+) ions] (Fe, Al, Mg, Na, K etc.) form an insoluble compound with fluorine in the stomach, making their used to focus infrared light absorption from the GI system difficult.  Fluoride combines with carbon to form a class of compounds called "fluorocarbons". Some of these compounds are used in air conditioning and refrigerator systems 2  25.10.2024 Fluoride in Plasma Fluoride in Plasma Two types of F are found in human plasma:  The amount of fluoride in hard and soft tissues is directly dependent on the amount of ionic F in the plasma.  Ionic (inorganic) form: free fluorine not bound to protein or other plasma components F accumulation in plasma;  Organic form: Fluorine, which is present in complex form depending on plasma  Increases slowly with age components, especially proteins  This accumulation is due to organic F Fluoride Distribution in Tissues Fluoride Distribution in Tissues  Approximately 99% of the F amount in the body is found  Except for hard tissues, an unchanged F in calcified tissues (bone, cartilage, tooth, tendon, nail, distribution equilibrium occurs between the F hair) plasma concentration and the extracellular fluid  In adults, 50% of the fluoride taken every day binds to and the intracellular fluid in the soft tissues calcified tissues for 24 hours  The remain is excreted with urine  In children, F, which is attached to hard tissues, may  Therefore, only 5% of the fluoride taken is increase up to 65% depending on age due to active retained in soft tissues bone and hard tissue formation  Fluoride binds strongly to apatite and other calcium phosphate compounds in the body, but this is not irreversible  The intracellular F concentration is always lower and the F in all body fluids (including saliva) also  It dissolves in the resorption-apposition mechanism of increases due to plasma concentration bone and hard tissues  Fluoride can return to plasma 3  25.10.2024 Fluoride Metabolism Fluoride Metabolism  The increase in the saliva F level will also increase the F amount in the mouth and with this increase, GI System the liquid in the mouth will be swallowed again and pass into the plasma Hard tissues Plasma Soft tissues %50 %75-90 %5  Thus, both the oral environment F level and the plasma F level will remain high for a longer time than it should be. Feces Saliva,sweat,tears %10-25 Urine  After fluoride intake, saliva fluoride level increases %45 by 2-5% Fluoride Metabolism Fluoride Metabolism There are some factors that affect fluoride absorption, excretion and There are some factors that affect fluoride absorption, excretion and metabolism: metabolism:  Nutritional status and diet composition: Fluoride absorption  The height of the living area from the sea: Hypoxia has an effect increases on an empty stomach, and foods containing fluoride on urinary pH. binding substances such as calcium reduce absorption.  Acid-base disorders: Excretion is delayed because some drugs, metabolic and respiratory diseases disrupt the body acid-base  Physical activity: Affects urine excretion. balance.  Renal disorders: Kidney disorders delay excretion. Kidney  Circadian rhythm and hormones: Fluoride intake time affects diseases in children are considered to cause enamel hypoplasia. plasma F level. The parathyroid hormone level is related to the plasma F level. 4  25.10.2024 FLUORIDE INTOXICATIONS Fluoride Toxicity  Acute fluoride toxicity: High fluoride exposure in once  Chronic fluoride toxicity (Fluorosis): A small amount of continuous and regular fluoride absorption for a long time Acute Fluoride Toxicity Acute Fluoride Toxicity  It occurs with rapid and high fluoride uptake and absorption at Lethal Dose one time the amount that causes death when taken at one  In some industrial areas, it may occur as a result of inhalation time of fluorine vapor and gases  Ingestion of soluble fluorine compounds (contaminated drinking water, food, insect and rat poison)  is proportional to body weight  It may occur as a result of topical fluoride applications.  It is calculated as 32-64 mg fluoride or 0.07-0.14 g NaF per 1 kg  The speed and severity of the response depends on;  the amount of fluoride taken  the child’s age  Approximately 5-10 g NaF for 70 kg adult  the weight of the child  Approximately 1-2 g of NaF for a 15 kg child 5  25.10.2024 Acute Fluoride Toxicity Acute Fluoride Toxicity Probably Toxic Dose Calculation Probably Toxic Dose;  is an amount that can lead to severe poisoning,  0-1 year old child: 10kg  50 mg F which may result in death. It requires urgent treatment and hospitalization  2-3 year old child: 15 kg  75 mg F  The probably toxic dose threshold is 5 mg / kg  4-5 year old child: 20 kg  100 mg F Acute Fluoride Toxicity Acute Fluoride Toxicity Fluoride content of some topical fluoride applications Fluoride content of topical fluoride applications  APF gel  12300 ppm F  5 ml APF gel  61.5 mg F  5 ml SnF2 solution  97 mg F  12300 mg/l = 12,3 mg/ml  1 ml NaF varnish  22.6 mg F  50 g 1450 ppm paste  72.5 mg F  50 g 1000 ppm paste  50 mg F  5 ml APF  61,5 mg F 6  25.10.2024 Acute Fluoride Toxicity Acute Fluoride Toxicity Fluoride content of topical fluoride applications  Probably toxic dose can be reached during topical fluoride applications  5 ml APF gel  61,5 mg F  The organs of the GI system are the first and most affected organs in case of fluoride toxicity  For example a 12 kg child;  The primary effect of fluoride toxicity is manifested by nausea and vomiting in the child  12*5 = 60 mg F --- probably toxic dose  This situation is caused by hydrofluoric acid formed upon the combination of hydrogen in  Toxic dose limit is exceeded gastric fluids with fluoride. Hydrofluoric acid is a stomach irritant Acute Fluoride Toxicity Acute Fluoride Toxicity  Initial symptoms of fluoride poisoning:  In the later stages,  Nausea  Muscle contractions  Abdominal contractions  Cardiac arrest  Vomiting  Loss of consciousness  Diarrhea  Coma  Increase in saliva and body fluids (sweating)  Death if not intervened within 2-4 hours  Dehydration and thirst 7  25.10.2024 Acute Fluoride Toxicity Acute Fluoride Toxicity  Administration of fluoride binding agent (Fluid replacement) First intervention in acute toxicity:  Since calcium binds fluoride in the intestine, it is recommended to drink milk in cases where the consciousness is open and the swallowing reflex is normal. Mineral waters, antiacid solutions containing Al  Inducing and increasing vomiting or Mg hydroxide also allow fluoride to bind.  Mechanically stimulated with the finger Acute Fluoride Toxicity Acute Fluoride Toxicity  If it is thought that the fluoride intake has passed to the  If muscle contractions begin, 10 ml, IV, 10% calcium plasma, the child should be hospitalizied immediately and gluconate should be given. the gastric lavage should be performed. When applying to a hospital or a poison information center, the following  The amount of urine should be kept high by giving information should also be provided; parental fluid and it should be discharged rapidly with diuretics.  Age, weight and condition of the patient  Name and content of the product  The speed of first aid is critical to the child's life  Swallowing time  Amount swallowed 8  25.10.2024 Chronic Fluoride Toxicity Chronic Fluoride Toxicity  It is a type of chronic disease caused by taking a small  If the chronic toxic effect of fluoride is seen in bone amount of fluoride for a long time and cartilage tissue, it is called «skeletal fluorosis»  It is called fluorosis. The degree of fluorosis depends on the frequency and amount of fluoride intake and the age of the person  Endemic skeletal fluorosis is seen in people living in regions that use drinking water above the optimal  Since fluoride tends to bind to calcified tissues, toxic effects level for many years in temperate climates can be seen in all calcified tissues Chronic Fluoride Toxicity Chronic Fluoride Toxicity  Early symptoms of skeletal fluorosis are pain in the joints and  These cases are mostly seen in limitation of movement those who live in industrial areas and volcanic lands  In these cases, osteosclerosis, osteoporosis, thickened hip bone and related findings are observed  These findings include;  In these regions, the fluoride rate in drinking water is 10 mg / l or higher  weight loss  bone fracture  anemia  For pathological skeletal fluorosis  weakness, joint stiffness to occur, 10–25 mg F per day is  development of discoloration in the teeth required for at least 10-20 years.  in more advanced cases, calcification up to tendons can be observed 9  25.10.2024 Chronic Fluoride Toxicity Chronic Fluoride Toxicity  Chronic fluoride toxicity in tooth enamel is called  Generally, different degrees of fluorosis can be seen from 1.5 dental fluorosis ppm according to the climate of the environment  In recent studies, it has been shown that the risk of dental fluorosis is increased in children who swallow toothpaste, if the child also uses fluoride tablets and if there is optimal F in drinking water, can cause mild dental fluorosis  Dental fluorosis is characterized by fluorine intake higher than optimal amount for a long time during the tooth development period. Mild Fluorosis Severe Fluorosis Chronic Fluoride Toxicity Dental Fluorosis  The risk of having dental fluorosis basically continues from birth to 8 years of age  The most critical age is between 18 months and 3 years, especially considering the incisors  Mild fluorosis is seen in areas with fluoride up to 3 ppm in drinking water. However, these teeth are resistant to decay. The cosmetic problem is controversial  If the fluoride in drinking water is above 3 ppm, a significant cosmetic problem occurs.  In our country, advanced dental fluorosis was detected in volcanic areas like Ağrı, Doğubeyazıt, Isparta, Edirne and Van regions. 10  25.10.2024 Chronic Fluoride Toxicity Chronic Fluoride Toxicity  Dean classification  2 classifications are often used for dental fluorosis: Classification Definition 0 No fluorosis - Normal 0,5 Questionable  Dean classification 1 Very mild fluorosis (opaque areas less than 25% of the tooth)  TF (Thylstrup-Fejerskov) Classification 2 Mild fluorosis (opaque areas less than 50% of the tooth) 3 Moderate fluorosis (all tooth surfaces are affected or there is loss of enamel) 4 Severe fluorosis (enamel loss affected at least half of the tooth) Chronic Fluoride Toxicity Chronic Fluoride Toxicity  Dean classification  TF Classification Classification Description 0 Normal creamy surface after drying 1 Faint white lines Normal Questionable Very Mild 2 Distinct white lines, with some merged 3 Cloudy opacities with white lines in between 4 Paper white opacities on entire surface Mild Moderate Severe 11  25.10.2024 Chronic Fluoride Toxicity FLUORIDE EFFECT MECHANISM  TF Classification 1. Prevention of demineralization Classification Description 2. Ensuring remineralization 5 Pitted and opaque surface 3. Prevention of acid production in plaque by 6 Merged pits form rows < 2 mm inhibiting bacterial metabolism and enzymes high 7 Irregular pattern of enamel loss 4. Prevention of plaque adhesion 8 ½ Surface enamel lost, remaining 5. To act as a fluorine reservoir during acid attacks enamel being opaque by forming CaF2 spheres on the enamel surface 9 Cervical rim of opaque enamel FLUORIDE EFFECT MECHANISM FLUORIDE EFFECT MECHANISM  Combination of fluoride with tooth enamel  The ionic radius and hydration coefficient of causes the outer layers of enamel to harden, and their structure and composition to change. the fluoride ion are the same as the hydroxyl group in the apatite of the tooth and bone  By inhibiting the demineralization process of structure. Thus, it can easily replace the enamel, it provides enamel remineralization, subgroup of apatites. enamel resistance to cariogenic substances increases and it reduces acid production in plaque.  Due to this feature, fluorides taken systemically or topically during the calcification process of the teeth can enter the structure of the enamel. 12  25.10.2024 Effects of Fluoride on Teeth Effect on Enamel  Fluoride has effects in terms of caries prophylaxis; The effect before teeth eruption;  When fluoride enters the enamel structure  on enamel of teeth before and after eruption during the formation of teeth, it affects enamel  on plaque formation formation through two successive and different  on the dentine of teeth events: Effect on Enamel Effect on Enamel  Before; it participates in various enzymatic events as a  The effect of fluoride during enamel trace element and plays a formation does not go beyond ensuring role in the synthesis of the healthy development and well-mineralization organic matrix of enamel. of enamel  In terms of caries prophylaxis, it is not  In the next stage; it acts as a important other than its contribution to the catalyst in the formation of formation of a quality enamel hydroxyapatites, which form the inorganic part of enamel. 13  25.10.2024 Effect on Enamel Effect on Enamel Fluoride in the maturation phase Effect on enamel tissue after teeth eruption; of enamel, This effect occurs either with topical applications  It enters in the structure of hydroxyapatite crystals and or topical effects of systemic applications easily replace with "OH" ions to form "fluoroapatite«  Some of the systemically ingested fluoride passes into saliva, increasing the fluoride level of plaque  Thanks to the formation of fluoroapatite, whose solubility is extremely low compared to  Reduces demineralization hydroxyapatite, a structure more resistant to tooth decay  Increases remineralization is formed Effect on Enamel Effect on Enamel Inhibition of demineralization;  If there is fluoride in the environment during the organic acid attack, this fluoride will leak towards the enamel and binds on the HAP surface and thus it prevent the crystal dissolution  In addition, it will bind calcium and phosphate ions dissolved from the enamel with the effect of acids and prevent them from leaving the environment  Fluoride will keep the medium saturated 14  25.10.2024 Effect on Enamel Effect on Enamel Increasing remineralization;  When fluoride is applied topically to the initial carious lesion, it first combines with hydrogen ions to reduce the acid effect. The acidic attack produced by the bacteria causes the enamel crystals to dissolve. Following this, buffering occurs with the flow of saliva.  Another effect of fluoride on the initial caries 1. As the pH starts to rise above 5.5, remineralization will lesions is to have a catalytic effect in the re- occur thanks to mineral-rich saliva. precipitation of calcium and phosphate ions, 2. If there is a fluoride ion in the environment, calcium and which are dissolved in the environment, on the phosphate dissolved from the enamel will settle back on teeth. the enamel surface together with fluoride and it will form FAP (fluoroapatite). 3. Both the remineralization rate and amount will increase. Effect on Enamel Effect on Enamel Increasing remineralization; 4. The solubility of newly formed fluoroapatite or fluorohydroxyapatite is lower than hydroxyapatite. 5. As a result of increasing and repeated remineralization attacks, the crystal becomes more mature. 15  25.10.2024 Effect on Enamel Effect on Enamel  In the post-eruption period, CaF2, fluoroapatite or fluorohydroxyapatite are formed depending on the agent used in fluoride applications  The main protective effect of topical fluorides is thought to be caused by the F release of CaF2 crystals  CaF2 crystals, which remain in the mouth for a long time, act as a fluoride reservoirs and help the enamel tissue to turn into fluoroapatite over time  For this compound to form, the oral environment must be in contact with more than 100 ppm fluoride for a while Effect on Enamel Effect on Plaque  CaF2 occurs in two steps:  Fluoride prevents the adherence of plaque to the tooth surface and the attachment of bacteria to the tooth in the plaque 1. First, some Ca is dissolved from enamel with acid attack  It increases the plaque pH by preventing acid production of plaque bacteria using glycolytic way 2. Then it combines with ionic F and precipitates into the tissue (fluoride come from topical  In addition, it has a bactericidal effect in high applications) concentrations.  Fluoroapatite or fluorohydroxyapatite are products intended to be created in enamel to prevent decay and it is called tightly bound fluoride. However, with routine topical fluoride agents, CaF2, generally known as loosely bound fluoride, occurs in enamel. S.mutans L.acidophilus 16  25.10.2024 Effect on Dentin Thank You…  Fluoride slows the progression of caries in teeth with exposed dentin tissue  Apatite crystals precipitate on the superficial layers of dentin tissue with the effect of fluoride ion, so, dentin remineralization occurs  In addition, fluoride, by combining with Ca, plugs the opening of dentin canals and plays a role in relieving dentin sensitivity Brugge, Belçika 17