Porcelain Veneers - Disadvantages.
A) Porcelain veneers have potential to break or come off.
One of the more significant disadvantages associated with porcelain veneers is the fact that they do have the potential to break or come off, and of course this will occur at a most inopportune moment. If a porcelain veneer has broken there is no way for your dentist to repair it, their only option will be to make you a new one. This means that you will have to endure the cost of having the new veneer made, as well as endure the time it takes for the new veneer to be fabricated and ultimately bonded into place. If a porcelain veneer has simply come off, there is a chance that your dentist will be able to bond it back in place.
B) Having porcelain veneers placed is not a reversible process.
Another disadvantage of porcelain veneers this the fact that this technique is not a reversible process. Although minimal, a noticeable amount of tooth enamel is trimmed from the front side of a tooth when a porcelain veneer is made. This means that once a tooth has been veneered its appearance and shape will never be pleasing unless the veneer remains in place (or else some other type of dental restoration has been created for the tooth).
For the most part this second disadvantage is only a concern if you are considering having porcelain veneers placed purely for cosmetic reasons (as in perfecting an already pleasing smile). If there are significant reasons why a tooth needs a cosmetic improvement, and your situation makes you a good candidate for this process, then porcelain veneers are more than likely the best approach.
When aren't porcelain veneers an appropriate treatment?
There are some situations where a dentist might conclude that certain teeth, or even certain people, are not good candidates for porcelain veneers. Some of these situations are:
A) Porcelain veneers cannot be placed on unhealthy teeth.
Porcelain veneers cannot be placed on teeth that have decay or are involved with periodontal disease (gum disease). These conditions must be treated by your dentist before a porcelain veneer can be successfully placed.
B) Placing a porcelain veneer on a tooth will not provide a strengthening effect.
If a significant amount of tooth structure has been lost as a result of decay or fracture, or else has already been replaced by a dental filling, the tooth may not be a good candidate for a porcelain veneer.
Porcelain veneers will not strengthen the teeth on which they are placed. Teeth that have histories where a significant amount of tooth structure has been lost are usually better served by placing a dental crown on them, not a porcelain veneer.
C) Porcelain veneers must be bonded to tooth enamel.
A porcelain veneer can only be successfully bonded to tooth enamel. Some teeth, as a result of excessive wear or previous attempts at dental bonding, may have little or no enamel remaining on their front side. These teeth do not make good candidates for porcelain veneers.
D) Porcelain veneers are not a good choice for people who clench and grind their teeth.
People who clench and grind their teeth can make poor candidates for porcelain veneers. The forces created by these activities, termed bruxism by dentists, can easily chip or break porcelain veneers.
A person may possibly be able to successfully control their bruxing habits during their waking hours, but during sleep a bruxer has essentially no control over this activity. If a person who bruxes does have veneers placed, they must be committed to wearing a plastic dental night guard when they sleep, so to minimize the amount of stress placed on their veneers.