The risks depend on the kind of treatment and how long a patient has braces or an appliance in. If you have any concerns, please talk to your orthodontist. Here are a few common things that can happen:
Cavities - it is harder to keep teeth clean with braces on and cavities can form around the brackets. White spots, which are the start of cavities, can also form. Invisalign or other removable trays are a good option if a patient is worried that they will not be able to keep things clean.
Gum overgrowth - Gums can become puffy and red if the teeth are not kept clean. Usually, gums will go back to being healthy after braces are removed but sometimes a gingivectomy procedure is required.
Mouth sores - These usually occur during the first week that a patient gets braces since the mouth is getting used to having something new. Some wax over the rough area and salt water rinses will help until the inside of the mouth toughens up in about 1 week. You can also get sores or ulcers from a wire poking too far out back - just call your orthodontist and get it clipped so it doesn't bother you anymore.
Root resorption - Moving teeth requires putting a force on them with the wire. If too much force is used or the force is used for a really long time, sometimes you can get root resorption of your front upper and/or lower teeth. Root resorption means that the roots of your teeth get shorter. If there is any concern, your orthodontist will keep track of this with a few x-rays throughout treatment. Now, more and more new bracket designs are being used that put very small amounts of forces on teeth, such as self-ligating or Damon brackets.
Gum pain- Food (especially popcorn kernels) can get trapped underneath the band or bracket and cause a small infection. Your orthodontist or general dentist can clean the area and resolve the pain.
Invisalign is a company that uses a series of clear trays, which you usually change every week. Your teeth appear a little more shiny when you have the trays in but it's a very esthetic option for adults and teenagers. 1) Attachments- A lot of people don't realize that you have to get attachments or "buttons" on some teeth. These are little blobs of tooth-colored composite material that allow the trays to attach better on those particular teeth and move them effectively. If someone is standing really close to you, they will be able to see these attachments. The attachments are removed with a dental handpiece at the end of treatment and your teeth are polished smooth. There is no damage done to your teeth during removal of these attachments and your teeth will be as smooth as before. There is no pain when getting or removing the attachments. If you notice that an attachment has broken, cracked, or popped off, let your orthodontist know right away!
2) Elastics - Another thing people don't realize is that you might have to wear rubber bands or elastics to help move your teeth into the correct bite. These get attached right onto your trays or from a little metal button on the back teeth. You have to change them 3-4 times per day. 3) Pain - The trays initially feel "tight" since they are putting pressure on the teeth to move them. People might think that there is less pain or discomfort associated with Invisalign but usually the discomfort is the same as with braces in the first week while your teeth are adjusting. Most people report that the same kind of "tightness" every time they switch to a new tray and then it goes away over the 2 weeks. An advantage of Invisalign is that you do not get sores from brackets or poking wires. If a part of your tray is rubbing up again your gums and causing discomfort , let your orthodontist know, and they can grind that part down so it is more comfortable. You can also smooth down the plastic edge that is bugging you with an emory board. 4) Wearing 22 hours per day - In order for the trays to work, you have to wear them 22 hours/day. They are taken out to eat and then placed right back in. You have to be 100% compliant with wearing them, otherwise your teeth won't move properly. If you feel you cannot remember to wear them all day, then braces might be a better option for you. 5) Cost - The Invisalign company has a very high fee to make the trays so the cost for Invisalign treatment is usually more than regular braces. There are 3 different kinds of Invisalign systems: Invisalign Full, Invisalign Express, and Invisalign Teen. The Invisalign Full and Invisalign Teen are for comprehensive treatment and include 1-3 refinements. Both of these cost about double than Invisalign Express. Invisalign Express only has 5-10 trays and is used to correct minor problems over a few months. 6) Retainers at the end- The retainers are the end of treatment are the same as you would get after braces. Usually, you would get a clear Essix retainer, that looks like your Invisalign trays and perhaps a bonded wire retainer on the inside of your teeth to hold their position. Retainer wear is lifelong. 7) Taking trays out - It takes a bit of practice to be able to take your trays in and out when you eat. The trays are really tight around your teeth, especially with attachments. Some patients have gotten very frustrated at not being able to take the trays out easily. Keep in mind, you should take your trays out to eat, and some people struggle with doing this at work during the first couple of days. People find it easiest to start at the back ends and work around getting the trays off. Be patient - you'll get the hang of it in a few days! 8) Refinements - Your orthodontist might show you on the Invisalign program how your teeth should look at the end. Usually, only 80% of this actually happens and you still need a bit more correction at the end. The orthodontist might have to take another scan of your teeth and give you another set of refinement trays at the end. The length of time with refinement trays can vary greatly from a few weeks to a few months. Usually, your attachments will be removed and new attachments added with the refinement trays. 9) Types of tooth movements - It is much more complicated to bring down teeth and close extraction spaces with Invisalign. If you need to have these movements, then braces might be a better option since it might take a lot less time. 10) Cleaning trays - Trays are cleaned at night by brushing them with a toothbrush and some toothpaste or mouthwash. It is much easier to brush your teeth since the trays can be taken off.