Fluorosis (disease), also known as dental fluorosis and yellow spots, is an endemic disease, a special type of tooth enamel hypoplasia caused by excessive fluoride intake by the human body during dental development. Dental fluorosis is a prominent symptom of regional chronic fluorosis (fluorosis), so it is also known as dental fluorosis. The absorption of fluoride in food depends on the solubility of inorganic fluoride in food, and the amount of calcium. If calcium compounds are added, the absorption of fluoride is significantly reduced. Animal experiments have confirmed that adequate vitamins A and D and moderate amounts of calcium and phosphorus can reduce the damage caused by fluoride to the organism. This means that high fluoride levels are not the only cause of dental fluorosis, as not everyone in areas with slightly higher fluoride levels in water suffers from the disease. There are two methods for treating dental fluorosis as follows Method 1: Abrasion and acid-etching coating method Two methods for treating dental fluorosis are suitable for dental fluorosis without substantial defects. The specific steps are as follows: ① Clean the affected teeth. (2) Choose a fine pointed diamond dental drill and grind from proximal to distal center, or from distal to proximal center, along the incisive edge to the cervical area. Drip water while grinding, and evenly grind away the stained layer 0.1~0.2mm while keeping it moist. Pay attention to the shape of the tooth when grinding, and do not deepen the stained plaque area and leave indentations. After grinding, rinse with running water. (3) The affected tooth is separated from the wet, dry the tooth surface, apply 35% phosphoric acid for 3 minutes, rinse cleanly with running water, and blow dry the tooth surface with an air gun. (4) Apply bonding agent, blow to a thin layer, and irradiate with visible light for 40 seconds to cure. ⑤ Swab the anaerobic layer with ethanol, and the tooth surface is smooth and shiny. Method 2: Composite resin restoration Suitable for fluorosis with parenchymal defects. The specific steps are as follows: (1) Wear away the labially colored or loose enamel, the thickness is generally 0.3~0.5mm. (2) Acid etching of the affected tooth: under the condition of moisture isolation, use a special small brush dipped in 35%~55% phosphoric acid to evenly coat the tooth surface for 1 minute. Acid etching time should not be too long, otherwise the formation of a layer of insoluble reactive substances; in addition, too long acid etching, can seriously damage the normal structure of the enamel, and can not increase the retention. It should be noted that the acid treatment agent should not flow into the gingival sulcus, and the acid etching should be followed by repeated rinsing with distilled water or running water to wash away the acid and calcium salt debris; the patient should never rinse his mouth during this process. Finally, blow dry the tooth surface with compressed air without oil mist, and the tooth surface is chalky or grayish white at this time. (3) coated with adhesive: use a small brush dipped in adhesive coated on the acid-etched tooth surface, lightly blow with an air gun to make it uniform, and should not be thick, otherwise, volume contraction, thermal expansion coefficient, low mechanical properties, easy to cause bonding failure. After 20 seconds of irradiation with visible light, the bonding agent can be cured initially. (4) Restoration: select materials according to the patient’s age, facial color and color of neighboring teeth, colorimetric in natural light; take appropriate composite resin, form with fingers, stainless steel sculpture knife, push and press on the desired site, not beyond the incision edge. The neck end stops at the gingival margin and cannot go deep into the gingival sulcus and cover the gums; the pushed composite resin cannot have air bubbles. Once the shaping is satisfactory, the material is cured with visible light for 40 to 60 seconds, depending on the thickness and color category of the material. The distance between the tip of the light guide rod and the material is as close as possible, generally not more than 1mm. For example, when the crown is too short, the sculpture should make the tooth near and far in the book less, the central part of the relative protrusion, so that the tooth appears longer, can increase the beauty. (5) Trimming and polishing: attention should be paid to the morphology of the labial surface and the occlusal relationship. Eliminate early contact and remove excess material from the gingival margin. The resin surface has a sticky anaerobic layer due to anaerobic, and the surface must be ground and polished. Use occlusal paper for orthodontic, anterior extension and lateral occlusion to check if there are early contact points. If there is, use diamond stone dental drill to grind away, and can appropriately reduce the tooth contact and reduce the occlusal force. Operating principle: from coarse to fine, under the drip, grinding speed of about 1000r/min, and finally polished with a rubber grinding cup or cloth wheel dipped in a very fine abrasive. The gold steel stone tooth drill and hemp light piece have coarse and fine, the general order of dressing and polishing is: coarse repair → fine repair → fine repair → fine polishing → fine polishing. After polishing, the resin refraction is consistent, the surface is extremely smooth, and it is not easy to deposit bacterial spots, just like a fine craft. Many kinds of composite resin on the market, its performance and method also have differences, the operator should carefully read the product manual of each factory before use, and then use according to the provisions, so as to get good results.