The principle of this method is to put bleaching solution into the tooth (the tooth itself is a cavity structure, and this cavity is the space occupied by the tooth nerve, called pulp cavity) to play a bleaching role from the inside out, so as to completely remove the deep pigment in the hard tissue of the tooth and achieve the effect of whitening the tooth. But this method is generally only suitable for dead pulp teeth. If it is a living pulp tooth, it needs to be treated with pulp first (that is, killing the nerve), which is not worth the candle.
2. Resin veneer
This method is to stick a layer of resin material on the outer surface of teeth to cover the color of teeth, and the effect is good in a short time. The disadvantage is that the microstructure of resin is honeycomb micropore, which is easy to be colored by food pigment, so it usually needs to be reprocessed in about 3-4 years.
3. Porcelain veneer
This method can be used if the teeth have no major defects but poor color. It reconstructs the shape and color of teeth by grinding the outer surface of the lip side (the side facing the outside) evenly, and then using dental porcelain materials. Because the color index of teeth can be accurately controlled, the cosmetic effect is better and the wear resistance is similar to that of teeth. Disadvantages are fragile and easy to collapse due to excessive external force; It may fall off when cutting hard objects.
4. all-ceramic crown
After the outer surface of the tooth is polished, the whole tooth is covered with the above materials to restore the shape, strength and beauty of the tooth. The disadvantage is that the amount of tooth tissue removed is large, which is in danger of penetrating the pulp. It is most suitable for patients with tooth defects or patients who have no conditions for veneer restoration.
5. Porcelain crown
The biggest difference between porcelain crown and all-ceramic crown is that there is an inner metal crown inside the porcelain crown. Because of the existence of metal crown, the strength is higher than that of porcelain veneer and all-ceramic crown, but the disadvantage is that the base metal crown will vaguely reveal the color of metal (precious metal crown can generally avoid color problems).
6. Laser whitening
It uses high concentration bleaching agent (such as hydrogen peroxide) with appropriate laser dose to catalyze, increase and accelerate the bleaching effect of peroxide, and selectively acts on pigment particles deposited on teeth to achieve bleaching effect; The light-absorbing macromolecules in the tooth structure are broken into small molecules, so that light is no longer absorbed, and the efficacy of safe whitening is achieved.
At the same time, proper dose of laser irradiation can seal dentin tubules, reduce dentin permeability and alleviate dentin sensitivity symptoms during tooth bleaching.
7. Cold light whitening
Cold light tooth whitening technology is a popular tooth whitening technology in Europe and America in recent years. It first applies a layer of whitening agent to the teeth, and then uses low-temperature cold laser to decolor and repair the teeth, so as to remove the tooth surface and achieve the effect of whitening.
The operation process does not touch the gums at all and will not damage the tooth structure. The whole whitening process only takes 30 minutes, and the whitening effect can last for about 2 years. If the consumption of pigment can be reduced or avoided after operation, the decoloring effect on lightly and moderately colored teeth can generally last for 6-8 years.