Wisdom Teeth & Retainers
Wisdom teeth do not significantly contribute to someone acquiring crowding of their teeth. See one of many articles.
Anterior teeth crowding (especially lower front teeth) can be regarded as a normal maturational event. You tend to see this crowding of teeth start to develop in the late teen years (which happens to coincide with the emergence of wisdom teeth - but there is no cause-and-effect relationship since the crowding is seen equally in people who are congenitally missing their wisdom teeth or have already had these teeth extracted for some reason). However, because of this coincidence in time, it is very easy to convince people of a cause-and-effect relationship - and there are many anecdotal stories about just that. So why do teeth move and become more crowded? Well, teeth are always moving our whole life. They move at different rates of speed at different times for different reasons. And, it is a good thing that teeth can move or else we would not be able to move them orthodontically. Teeth move within the bone due to forces applied to the teeth. Typically, teeth stay contained in a balance between pressures from the tongue; pressures from the lips and cheeks; and pressures from chewing, biting, and clenching or grinding. Orthodontists move teeth with continuous gentle forces. So why would teeth crowd with age? There may be several contributing factors, but most typically, a person in their late teens has developed more muscle, and has more stresses in life (e.g. relationships, schooling, leaving home,...) and they will deepen their bite (i.e. acquire more overlap of their teeth vertically; deeper overbite) and to accommodate this vertical change, the lower teeth need to crowd (or less typically, the upper teeth need to space apart). The upper teeth fit over and around the lower teeth like a cap fits onto a bottle. Once the lower teeth get misaligned, because of this cap on a bottle fit, the upper teeth may start to acquire irregularities too as the lower teeth can act like a template for the positioning of the upper teeth.
No doubt you might find this very discouraging if you have concerns about teeth crowding after orthodontic treatment. Well, this is a concern for us too and we have often told people that sometimes it is harder to keep teeth straight than to get them straight to begin with. That is why we use a 2-retainer system for keeping teeth straight following most treatments. As one part of this system, typically, our office use upper and lower fixed lingual retainers. These are little, thin wires bonded to the tongue-side of the front teeth. See the picture:
Usually we bond such retainers to the top and bottom anterior teeth. These are very good long-term retainers. Dr. Clarke has had one bonded to his own teeth for approximately 15 years. (We do not use words like "permanent" or "forever" when discussing these retainers since they are only bonded to the teeth and they will eventually become loose at one or more teeth). A person may notice a loose wire themselves, or it may be noticed when someone is visiting their family dentist and hygienist for a dental cleaning. In the future, when such a wire retainer becomes loose, a person can return to an orthodontic office and request that the wire be removed or that it be repaired and bonded again. If someone requests that it be removed, we would remind the person that teeth tend to crowd with age and if they'd like to ensure that their teeth stay straight, then we would recommend that they have the wire bonded again. The only time that we would be in favour of removing such a retainer wire is if the person does not floss those teeth and/or brush vigorously enough around the wire. Flossing can be done quite easily with the use of Superfloss and/or floss threaders and our staff provides samples to all of our patients and trains them how to use this. Once your fingers have tried the technique a couple of times, it is quite easy. Please see the picture below:
In addition to the two fixed lingual retainers, we provide patients with a clear, removable nighttime upper retainer called and Essix retainer. See this image:
We usually instruct patients to wear this every night for the first year after they finish their orthodontic treatment. After that period of time, the instructions become individualized. They become individualized because not everyone is the same with respect to how straight their teeth will stay. For some people (very few) they may be able to never wear a retainer and their teeth would stay straight. Other people (very few) will experience their teeth starting to move unfavourably after just a few days of not wearing their Essix retainer. And, most people will find themselves somewhere in the middle between these two extremes - you just don't know where you'll be. So, after the first year of nighttime Essix retainer wear, we will ask the patient if they would like to continue with this. Some (many) patients say yes since they are very comfortable with this and have this as part of their bedtime routine and they do not want to change. Further, some people know that they tend to grind their teeth at night and want to keep wearing their Essix retainer nightly in order to prevent tooth wear. Now, other people will be interested in starting to taper-off the number of nights that they wear their Essix retainer. For these people, we suggest that they start to wear their Essix retainer every-other night for the next few months; and then a couple times a week. We inform them that they can keep tapering-off from the Essix retainer wear until they reach a point in time where they find that the retainer is starting to become tight and/or their teeth are sore in the morning. Once they find that level of frequency of Essix wear, they can start to wear their retainer slightly more frequently so that the retainer does not fit tightly (only passively) and their teeth are not sore in the morning. I never tell people not to wear their Essix retainer. They can always do this testing of its fit. Otherwise, teeth move with aging to some extent.