Whether dental veneers are permanent or not, in fact, no dental treatment can use the word permanent, including implants, more would say a semi-permanent material, veneers are the same. The veneers are divided into resin veneers and porcelain veneers. Resin veneers, the resin material itself will have an aging process, there may be a few years after the staining, discoloration or part of the resin material off, it is necessary to carry out a retreatment process, re-production of veneers. In addition, if you do porcelain veneers, porcelain veneers this material is more stable compared to resin materials, in terms of discoloration will have a great improvement, but porcelain is the same as a bowl, if in the process of daily use accidentally touched some hard things, may also appear chipped porcelain, if chipped porcelain also need to remove, re-production, re-paste. Another is that porcelain veneers are bonded to the surface of the teeth by adhesive, this adhesive may slowly dissolve over time, resulting in porcelain veneers fall off. The veneer itself is very intact and can be re-bonded. If they fall off, the porcelain veneers are no longer usable and need to be retreated. There is also a case that the porcelain veneer is only placed on the lip side of the tooth, but the tooth is a three-dimensional structure, and there may be tooth decay on other sides or the intersection. The secondary caries, at the same time to the caries for caries treatment, and even may lead to the original porcelain veneers can no longer be used, to re-production.