November 26, 2019
There are many misconceptions about porcelain veneers, but perhaps MOST common is that porcelain veneers ruin your teeth. To be fair, the short answer is “maybe”, and that is where it becomes difficult from a consumer standpoint. Yes, we are irreversibly removing “some” tooth structure (generally, as much as we need. Sometimes little to none, but sometimes ½ mm or more). Even if NO tooth structure is removed, if the decision to remove the veneers at a later date is made, the process to remove the veneers will remove some tooth structure as well.
Is removing tooth structure a BAD thing? Some dentists will passionately say yes, while others are more indifferent. If the REPLACEMENT of tooth structure is poorly done, then yes, I think everyone would agree that it was a bad thing. However, if done properly, well prepared teeth and well bonded porcelain veneers can last a VERY long time (perhaps a lifetime).
Proper Tooth Preparation for Porcelain Veneers
Less is more. That is a common phrase with many intentions. In THIS case, it simply means that the less tooth structure we must remove, the more we have later if we need to remake or redo the case. If a dentist is aggressive with removal of enamel and dentin, the NEXT dentist will have less to manage. It MAY even appear that the first dentist was “great” and the next dentist is “less than”, and it may be the opposite.
So how much enamel removal IS needed? If teeth are perfectly aligned, maybe none. However, the result MAY feel bulky. A more common approach is to remove 0.3-0.5mm of tooth, and the porcelain restoration would be the exact same thickness. This means “net zero” or no change in tooth size/thickness and would feel very natural.
As Much As Needed
Sometimes, the tooth itself tells us how much to remove. The most common way or reason is when the patient wants a bright white smile. If the natural tooth itself is very dark, then this color would “shine through”, so in order to get the desired color, we must remove MORE enamel/dentin to allow the restoration to be thick enough to block out the natural color.
Another reason is due to previous dentistry. It is very common that teeth have already “had work done” and the porcelain veneers are an upgrade of sorts. If a tooth already has a large filling, then the porcelain veneer, crown, or onlay will need to be larger than normal. If restored properly, this is not a significant issue.
Properly Bonded Porcelain Veneers
This is where it gets tricky. Every dentist has “their way”. It stands to reason that “their way” should be similar/identical to the manufacturer’s instructions, but that isn’t always the case. I will go on record and say that if you find a dentist that reads the instructions from the box that his materials came from, you likely have found a dentist that has work that lasts longer and is more comfortable than other dentists that do things “off label”.
Traditionally, the tooth surface is etched in order to accept the primer and bonding agent during the bonding process. Some more recent materials combine the etch with the primer, but these products may not last as long as more traditional materials. Get a group of dentists in a room, they will debate this step for years….!
The enemy to the bonding process is moisture. To a degree. Common problems are blood contamination, saliva contamination, and anything else that would spoil the bonding process. This is why a good dentist will use isolation to control the amount of moisture present. If moisture is the enemy, one would think that totally dehydrated teeth would be best; however, this isn’t true. We need the tooth “sorta moist”, so there IS a level of moisture needed to bond the porcelain veneer.
Disinfectants and Desensitizers
When the tooth is ready to be bonded to, it is common to place solutions that “soothe” the tooth and disinfect.
Not all dentists do this step, some claim it is not necessary, but I feel that the end result is more comfortable and longer lasting. With an investment like a porcelain veneer smile makeover, we do our best so that our patients get the best value, and part of that is that they last as long as possible.
It is not unusual for a patient to feel that they replaced all of their teeth and no longer need to brush or floss. “Why would I? My teeth are gone!”
This isn’t true. The teeth are still there, they are simply covered up, or partially covered. If you don’t want to have porcelain veneers ruin your teeth, be sure to brush, floss, visit your dentist as recommended and follow ALL advice from your dental office.
August 17, 2018
Smile Makeover Requirements
by Lance Timmerman DMD
“I want a new smile, what will it take?!” Seattle cosmetic dentist Lance Timmerman in Tukwila gets this a lot. The challenge: an answer. If I asked you to paint my house, could you give a fee? Probably, but at first you may only give me a range and after you learn about the condition of my house you can give a better estimate.”