Century Orthodontics

What's Next?

2012-02-28T12:23:00.001-08:00

After I am finished with my orthodontic treatment what comes next?

After you are finished wearing braces or Invisalign the next step is retention. Retainers come in many shapes and sizes. Each patient is special and has special needs for their teeth so retainers vary from patient to patient. Whatever type of retainer is chosen for you should be worn for as long as you would like to keep your teeth straight. So if you would like your teeth to stay straight forever, the only way that you can ensure that they do is to wear a retainer for 4-12 hours everyday or as instructed by the doctor.

In our office we typically use these retainers for these types of orthodontic procedures:

Full fixed (Braces)- Traditional retainer and a bonded (glued in retainer).
Invisalign- Essix (clear in office invisalign type retainer) or a Vivera (made by Invisalign)

What does it mean?

Types of retainers and their pros and cons:

Traditional Retainers- These retainers are an oldie by a goodie. They are more bulky but they have lots of advantages. These retainers can last 20-30 yrs and still do a great job. These can have a picture or color choice added to them so that they can show off your personality. These retainers can be adjusted if teeth have moved and are more forgiving if you slack in wearing them a few nights. Traditional retainers also are a little less comfortable then the other types of retainers.

Bonded Lower Retainers- Are a great way to keep your teeth straight and not have to worry about remembering to put it in your mouth. These retainers are one of the easiest to wear but one of the hardest to keep clean. Glued in retainers make it difficult to floss and to brush behind but it is possible.

Essix Retainers- These in office clear plastic retainers are super comfy and invisible but they do have a few drawbacks. These retainers are great but only last about a year to a year in half just like contact lens. They can become expensive if you are going to wear them for a life time because you have to replace them yearly. (About $100 an arch)

Vivera Retainers- Invisalign's retention appliance is a great option for patients who love the clear aligners but aren't available to get to an orthodontist every year. These retainers are made by either taking an impression or a LED Scan. They are made by Invisalign and are made 4 sets at a time. So you won't have to come back in for appointments yearly. Also the scans are saved by invisalign so as long as your last aligner fits you may never have to take an impression again.

How Much Do I Wear My Invisalign

2012-02-28T10:54:00.000-08:00

How much do I wear my Invisalign aligners?

Patients that are moving teeth and are wearing Invisalign appliances should wear their aligners anywhere from 23-22 hours everyday to get the best optimal wear. This amounts to taking them out only to eat or to brush. One nice thing about Invisalign though is if you have a special occasion or a meeting or even photo shoot you can take them out and just make up the time you lost at the end of your two week process. Certain days you may not want to risk losing them so you can just keep them in a safe place and just add a day at the end. The one thing that you must always do is wear them for the full two weeks. Each aligner is only designed to do 100% of its job it can not do anymore than that so if you aren't wearing your aligners enough you will build an in correction into your future aligners.

Smiles Change Lives (message from a Patient)

2012-02-07T08:42:00.000-08:00

This is a letter from one of our Smiles Change Lives Patients. (Smiles Change Lives is an affordable nonprofit orthodontic program)

Smiles Change Lives

When I saw smiles change lives I didn't think that a brand new smile could actually change a person's life, but I know now for a fact that it can. Having braces for the past year and eight months has been a life changing experience for me. I went from not wanting to ever smile or laugh to smiling and laughing all the time. Sometimes people even ask, "Jasmine why are you smiling for no reason?" I used to envy people with pretty smiles. I've been waiting on this day for a long time and now that it is finally here I can't believe it. I just want to thank everyone who is a part of the reason why I can smile and laugh without being afraid; having a new smile is a brand new beginning.

Thanks,
Jasmine

"Shopping" for Orthodontics?

2012-01-30T09:26:00.000-08:00

Would you pick a heart surgeon on price alone? Now teeth are not quite life and death, but they do play a huge part in your appearance and well being!

Braces and Invisalign are simply tools. The results that are achieved are entirely dependent upon the skills of the doctor and staff. When evaluating your options, this is the most important factor to consider in your buying decision.

Our doctors are specialists in the field of orthodontics. Trained in all aspects of orthodontic diagnosis and correction, they have the ability to utilize many different techniques to get the best possible results in the minimum amount of time.

Our practice was a pioneer in the use of Invisalign since its inception in 1999 and our disignation as an Elite provider puts us in the top Invisalign practices in the country. Only 1% of orthodontics reach this status.

How We Practice

Unlike most group practices, treatment at our office is a mutual collaboration, with Dr. Waxler and Dr. Cavanaugh jointly diagnosing, treatment planning, and treating most of our patients. We feel that the advantages of multiple insights has been extremely beneficial for our patients. We do understand, however, that certain patients may desire or require a particular doctor.

Where We Come From

Our practice has been around for a very LONG time, over a century. Dr. Edward Angle is considered around the world to be the father of modern orthodontics. Among his many accomplishments were the invention of the edgewise appliance which are the "braces" used by the majority of the world's orthodontists, establishing the world's first school for orthodontic education right here in St. Louis in the year 1899 and finally founder and first president of what has become the American Association of Orthodontists which has its headquarters here in St. Louis. As we traced our origins, we were pleased to discover that our founder and predecessor was this very same Dr. Angle, who started his private orthodontic practice in 1896. His practice has changed hands and moved locations through the years but has always remained intact.

How do I know if I have a type of gum disease?

2011-12-19T12:11:00.000-08:00

You may not have painor any “problems,” but there are a few ways to tell if you need to go see yourdental professional. Some reasons are yourgums bleed when you are brushing or flossing, your gums are red and swollen, and you have mouth sores or bumps that will notgo away. When you are at the dentalprofessional’s office, it is important that you ask what steps to take toimprove your oral hygiene. Even thoughyou maybe brushing you may be doing it incorrectly or not long enough.

Clean teeth & Gums, What's the point?

2011-12-05T09:57:00.000-08:00

Keeping your mouth healthy and clean is an important part of your overall health. When teeth are not being taken care of, they tend to build up plaque and tartar. This build up creates bacteria that causes irritation to the gums causing bleeding and a low grade infection. This infection is called gingivitis. People who have gingivitis are more likely to have heart problems, suffer a stroke, or heart attack. You are also more likely to have a hard time controlling blood sugar and blood pressure problems.

Helmets and Mouth Guards

2011-11-29T10:26:00.000-08:00

Sports safety is a very important thing to think about when getting involved with any sport. In the past it was seen as un-cool to wear a helmet when riding a bike. In some cities in the US laws are passed to enforce the importance of wearing one for your safety. By spending $20 on a bike helmet, you could not only save yourself from a concussion but also your life. Helmets keep players alive and prevent 1 head injury every four minutes. A face guard is attached to the helmet completely covering the face. This makes players 35% less likely to have a facial injury.

When playing any sports where the player could get hit in the mouth, a mouth guard is needed. People don’t realize that by wearing a mouth guard this decreases the odds of injury to your lips, teeth, and even your brain. When protective mouth wear is being worn correctly, it can decrease the chance of getting a concussion. Mouth guards can range anywhere from $5-$150, but rehabilitation costs for a single tooth knocked out can surpass the price of a custom made mouth guard by 20 times. Most of the sports related injuries happen at practice. So that means not only do you have to wear a mouth guard and helmet during the games but also at practice. In orthodontics we have lots of teens who play a wide variety of sports and extra activities. Some of the most dangerous sports are not ones that you would think would be dangerous. Cheerleading and gymnastics as well as horseback riding are all activities where we have seen a lot of broken brackets and mouth injuries. We see a lot of these injuries because people don’t see them as dangerous and don’t take the precautions that they would for football or hockey. This year alone 5 million teeth will be knocked out while people are playing sports. We at Century Orthodontics hope that you do not become part of that statistic.

No More Goopey Mess

2011-10-19T07:58:00.001-07:00

Invisalign Intraoral Scanner

Our goal at Century Orthodontics has always been to be the St. Louis Leader in Invisalign treatment. We were the first in the Missouri to use Invisalign and we have consistently been one of the top Invisalign providers in the country. That's why we are the first orthodontic office in St. Louis to acquire the iOC Invisalign intraoral scanner. The scanner will allow us to do away the gooey impressions that are normally used to created 3-D models of the teeth. While this machine costs as much as a nice new car, we feel that our patients are worth it!

The benefits of a 3-D dental scanner:

-no need to have impressions taken, leading to a much more comfortable experience and no gagging

-increased accuracy leading to better fitting appliances and thus better control of tooth movement

-elimination of rejected impressions and redo’s

-ability to see the 3-D image of your teeth immediately following the scan

-Ability to view Invisalign tooth animation in a few days vs. a few weeks, allowing us to start treatment 50% faster

The scans generally take between 15-20 minutes, which is comparable to the time required for a full set of impressions. Unlike other scanning systems, iOC is a laser and optical scanner, so there is also no concern about any radiation.

Our office has scheduled 3 days of hand-on training and will begin using the scanner for most Invisalign and Invisalign Teen patients shortly. We think this is going to really improve the overall Invisalign experience and look forward to helping you smile without braces!

What are Rubber Bands for?

2011-08-25T11:23:00.002-07:00

Everyday at least one of our patients will ask, "Why am I wearing these rubber bands?" Patients wear rubber bands for many different reasons. Common reasons are to fix bite problems or to help guide the movement of teeth. Patients for the most part find that wearing their elastics is one of the most annoying parts of braces, but it is also one of the most important parts to getting the teeth straight and to having proper bite.

Why do I wear elastics? These elastics create a small but continuous amount of pressure on the teeth or jaws to move them into more desirable positions. If you wear your elastics as instructed, treatment will be completed more rapidly. When you are wearing your elastics full time, this means 24/7, taking them out only to eat and brush. We ask our patients to switch their elastics 3-4 times daily. Switching them ensures that the elastics will retain their strength, and the force will be steady. Your teeth will be sore when you start wearing your rubber bands, but the better you are with wearing them the sooner the soreness will go away. Just smile through the first few days, and your rubber bands will become easier and easier.

For patients wearing elastics the most difficult time of the day is right after lunch. Patients forget to put their rubbrt bands back in until after they get home from school or until after dinner. Forgetting will bring tooth movement to a halt and extend the amount of time in braces. It takes 10-12hrs for the teeth to start moving when wearing elastics.

Dr. Waxler tells patients their teeth are like semi-trucks. If two vehicles are on the highway and one is a sports car and the other is a semi-truck, they both can do the speed limit but when they have to come to a stop, it only takes the sports car a few seconds to accelerate back up to the 60 miles an hour. The semi-truck takes a lot longer to reach the speed limit. This is why those big trucks don't want to stop if they can avoid it.

Since your teeth are like semi-trucks, the only thing to keep them from stopping their movement is to wear your elastics as instructed. Teeth will stop moving if the elastics are out of the mouth for more then just eating and brushing. We tell our patients to put their elastics on their pinkie fingers when the bands are out of their mouths. When you are finished eating and brushing, you will look down and remember to put them back in

How long do I need to wear my retainers?

2011-03-22T08:43:00.000-07:00

How long do I need to wear my retainers?

This is a question that is asked almost everyday in our office. The answer is an easy one, you need to wear them as long as you would like to keep you teeth straight. If you would like your teeth to be straight until you are 90 then wear your retainers until you are 90. We can only insure that your teeth stay straight as long as you wear your retainers and they fit properly. Dr. Waxler always says "Our bodies are ever changing no matter how long you've held your teeth straight they can still move as you get older. Even people who had "perfect" teeth when they were young, often find their teeth moving slightly as they age.

So what good were braces?

The secret of a good orthodontic result is to put the teeth in the most stable position that is possible considering the person's facial structure and dental problems. After a few years in retainers, the tooth arrangement should be reasonably stable; although corrected dental and skeletal problems all have varying tendencies to "rebound". This is like people who always have to be on a diet or wear glasses to correct a problem, some teeth need to be retained forever.

If I decide not to wear my retainer...., should I still see my Orthodontist?

After approximently two years of retainer wear we enter into a post-retention period. We require appointments on a "as needed" basis. Unless you are told that your problem is particularly unstable, you may only need to wear your retainer 2-4 nights a week. If you lose, break or your retainer no longer fits please call our office to make an appointment so we can advise you on what options will fit your situtation best. If you have graduated from our office there may be an office visit charge or a replacement fee.

What about my bonded (or glued in) retainer?

You may come back to see us anytime to have our office check your bonded retainer, but your regular dentist can evaluate this retainer for you at your dental check ups. If anything appears to be wrong please call us immediately to have it checked. If we need to remove this retainer we suggest getting a removable retainer to ensure that your teeth will stay straight. You may have this retainer removed at anytime and take an impression for a removable retainer to be made (at the current fee). This removable retainer will be asked to wear at night time for as long as you would like to hold those teeth straight.

Extractions

2007-10-02T13:18:00.001-07:00

Premolar Extractions Controversy

There is probably no facet of orthodontic treatment that has caused as much controversy as the decision to extract, or not to extract, permanent teeth: and more specifically, whether to extract four premolars or to “develop” room for non-extraction treatment.

Besides the obvious reasons of avoiding the trauma and expense of surgery, and the desire to preserve permanent teeth; other alleged negative sequela, such as TMD problems, flattened facial profiles, and “dark buccal corridors” have contributed to the premolar extraction controversy. Like a pendulum, the popularity of premolar extractions has swung back and forth, between the extremes of non-extraction at any cost and “routine” extractions to achieve arbitrary cephalometric norms.

Some of the factors we consider are:

When dealing with a fairly “normal” orthodontic problem (no gross asymmetries) the decision to extract four premolars is straightforward although often not easy. It is impossible to extract less than a whole tooth, and usually the extraction of a tooth on the left requires an extraction on the right to balance the midline. Likewise, lower extractions usually require upper extractions (and visa versa) to prevent excessive overjet or underbite. These parameters normally lead to extraction of four first premolars or to treat as a non-extraction case. There are times when upper premolars only, a single lower incisor extraction, molar extraction, or interproximal enamel reduction (IPR) are appropriate but, in general, the decision for extractions is often framed around “4-bi’s”.

Given the usual all or nothing nature of the premolar extraction decision, it is no surprise that different orthodontists often appear to have conflicting treatment plans for the same patient. The reason is not that they see very different problems or have radically different philosophies of treatment, but rather that each doctor has a different line in the gray area between extractions and nonextraction. Two treatment plans that appear very different can both be based on a similar analysis of the patient’s problem, but end up with very different treatments due to the black and white nature of the decision making process.

It is important to understand that in borderline cases there are no correct or right answers. Both treatments performed by competent orthodontists would produce a good result, but neither is perfect. Each option would have pros and cons, and orthodontists and dentists could (and do!) spend endless amounts of time debating which option is “right”.

We try to avoid extractions as much as possible, but extractions should be considered when esthetics and stability call for it. Truthfully, almost any patient can be treated without extractions and, often, this is technically the easier way. This is the reason that the weekend orthodontic courses aimed at general dentists almost always stress nonextraction treatment.

Where there is a conflict between facial esthetics and dental stability, it is our judgment to favor esthetics. This is not to say that patients with flat facial profiles and extreme crowding should be treated without extractions, nor that patients with full profiles and large tongues should have teeth extracted, but rather that esthetics should be the primary determinant of treatment in any borderline situation. In these cases it is very important that the patient understands the necessity of long-term retention

Contrary to the beliefs of many nonextraction proponents, good scientific studies (evidenced based) done on TMD and orthodontic treatment fail to show any correlation between the development of TMD type problems and the extraction (or nonextraction) of teeth. All dentists can remember patients who develop TMD problems after extraction treatment and, if you feel there is a correlation, you will fixate on these patients. Statistically, you are just as likely to find TMD problems in patients treated nonextraction or, for that matter, patients who never received orthodontic treatment at all.

Scientific studies have also shown that well treated extraction cases do not adversely affect facial profiles. Again, it is easy to visualize patients with flat profiles who have had premolar extractions. Assuming a good treatment decision, these patients would have had a flat profile even if they never had treatment (and an extremely unstable dental alignment if they had been treated without extractions). The truth is: tight facial structures (flat faces) lead to crowding, which leads to extraction rather than extractions cause flat faces. As a matter of fact, the most dished in and flattened faces often belong to those patients whom we have treated without any extractions. Like the TMD controversy, negative esthetic effects attributed to extractions fall into our favorite logical fallacy “post hoc ergo propter hoc” (after this therefore because of this). Other studies have also shown that dark buccal corridors and a narrow smile are not “caused” by premolar extractions.

A good selling point for premolar extractions can be a patient with moderate crowding and well-formed and positioned third molars. Treated without premolar extractions this patient usually needs third molars removed. Extract premolars, close some of the space by mesial movement of the posterior teeth, and hopefully the thirds can erupt and be kept—an exchange of four small, easily removed teeth for four molars that would be difficult to extract. Unfortunately no guarantee can be made that the thirds will always come in with enough room.

There seems to be a great deal of confusion about early expansion treatment (AKA arch development or growth modification). There is a important difference between expanding a constricted upper arch to match a normal lower arch (OK) and significantly expanding both arches in a patient whose arches may be narrow, but are in a normal transverse occlusal relationship to each other (not OK). Although it is possible to upright lingually verted lower posterior arches (which may have collapsed in, to compensate for a narrow maxillary arch), it is not possible to expand the mandibular basal bone, as there is no suture to distract as in the maxilla. Of all the inviolate “facts” of orthodontics, one of the most established is the stability of the lower inter-canine width. Expansion beyond the original width is almost a guarantee of collapse and recrowding.

Every decade or so a new “magic bullet” comes along promising the ability to create space and avoid extractions or unstable expansion. The latest iteration of this is the Damon™ orthodontic bracket with its manufacturer’s promise of extremely light forces that “grow” more room than regular braces. As usual, no good science backs up these claims!

In an attempt to avoid first premolar extractions, various alternatives can be considered:

o Expanding the arch, especially in a flat-faced individual, is often preferable to extractions, with the understanding this is an unstable correction and perpetual detention will be needed.

o For patients with a good posterior occlusion, a good upper arch with relatively small upper incisors, moderately severe lower crowding, and minimal overbite, the extraction of a lower incisor can be considered. Extraction of an incisor should be evaluated very carefully, for it can result in an untreatable problem with excessive overjet/overbite in the wrong individual.

o Interproximal enamel reduction (IPR) can provide a moderate amount of room but should be reserved for older patients. Excessive IPR as an initial treatment complicates the orthodontist’s ability to correct minor relapses in the future.

o Consider extraction of second premolars rather than first premolars. Theoretically, this reduces the amount of anterior retraction when only some space is needed for crowding and the facial profile is acceptable. This works best when the second premolars resemble the first, but large, molar-like second premolars may provide too much room and small, canine-like first premolars may not work against first molars.

o Distilization of full arches is very difficult so extraction of third molars or even second molars to provide anterior room has never been shown to provide significant space. With the advent of temporary anchorage devises (TAD’s) this may become a “new” way to treat nonextraction…. we’re already trying it!

Bottom line: Extractions are just a tool, not good or bad in themselves. Used right, they improve the quality of treatment, used wrong they may create a poor result.

Class II

2007-10-02T13:17:00.001-07:00

Our second topic: why are there so many ways to correct “Overbites”

Class II malocclusions or overjets (commonly, but incorrectly, called “overbites”) are one of the most common problems in orthodontics. Despite the customary Angle Class II classification, patients who exhibit excessive overjets are not a homogeneous group. The following all can produce excessive overjets.

Ø Protrusive maxilla
Ø Deficient (retrognathic) mandible
Ø Good posterior occlusion (Class I) with flared upper incisors
Ø Good posterior occlusion (Class I) with lingually verted lower anteriors
Ø Good skeletal alignment but the maxillary dentition is mesial to the mandibular dentition
Ø And of course a combination of 2 or more of the above problems

In addition to these sagittal problems, the vertical facial pattern influences the degree of overjet and the ease of correction. Further complicating the correction is the amount of growth the patient has left, as all class II problems are much harder to deal with when the patients are skeletally mature.

Understanding that Class II’s encompass a variety of problems makes it easier to see why there are a variety of ways to correct these problems. And, going with the theme of our newsletters, different orthodontists have different “philosophies” on how to achieve this correction.

As every orthodontist will tell you: most class II malocclusions are caused in large part by a deficient mandible. So why has so much traditional orthodontic treatment been aimed at retracting the maxilla and maxillary teeth with the use of headgears, molar distilizing appliances, upper premolar extractions and elastic band wear? The simple answer is: “its hard to grow mandibles” (some would even say it is impossible to “grow” mandibles!) Unfortunately computers don’t know this, and many patients are “promised” great facial improvements with the newest patient education software; and orthodontic companies and labs have an incentive to sell these innovative appliances. The fact that a promoter can show you anecdotally a patient who seems to have had a great response to a “mandible grower appliance” is no guarantee that this can be done on a regular basis.

Over the years various appliances such as the removable functionals e.g., Bionators, Activators, Frankels, Twin Blocks, Monoblocks, and the fixed “functional” appliances e.g., Herbst, MARA, Forsus, have been tried with the aim of stimulating mandibular growth over and above what would normally occur. As they have been “introduced” they were met with a great deal of enthusiasm followed unfortunately, a few years later, by disillusionment and a jump to the next silver bullet. Nonetheless many orthodontists (and general dentists) believe very strongly in this type of treatment. Why is that? Well often they do seem to work! Overjets do correct, but the big question is: do they “grow” mandibles and if they don’t are they worth the effort?
Being human we often see what we want to see. If we put in an appliance promoted to “grow” a small lower jaw and 6 months later the overjet is corrected, the logical assumption is that the appliance did what we wanted it to do! The facts however are that growing mandibles is one aspect of orthodontic treatment that has been well studied. The scientific consensus is that there is no or minimal long-term increase in mandibular growth over what would have been expected from normal growth. The overjet correction was really obtained in the same fashion as traditional orthodontic treatment: incremental improvements of the maxilla, mandible, and both dentoalveolar arches. Of course there are cases where one can show very significant improvements in mandibular position with the use of these appliances, but these cases are unusual and unpredictable, and probably would have occurred with more traditional treatment. Nevertheless we do use these appliances; sometimes because they require less patient cooperation (the fixed versions), and sometimes because the patient is so obviously mandibular deficient that we hope that we may get lucky and get a great response.

So what are some of the more predictable treatment options for “overjets”?

Ø In growing individuals headgears still work well to slow the maxilla’s normal forward growth and let the mandible catch up. Sometimes this is a good option while waiting for tooth eruption and fixed appliance therapy and a great option if the maxilla is protrusive. Of course getting sufficient wear is a major problem.
Ø For patients with mild to moderate class II’s, elastic bands work well but they have the “side effect” of pulling the lower dentition forward off the bone support. There is an esthetic and stability limit to how protrusive the lower anteriors can be. And, with the natural mesial movement of the teeth in the arches over time, excessively protrusive anteriors can become unacceptable 10, 20 and 30 years later. For patients with crowding, the excessive lower protrusion can be overcome with lower extractions. Although much easier than headgears, elastic cooperation can be a problem with certain patients.
Ø Upper first premolar extractions can be used; especially with severe Class II’s with good lower arches in nongrowing patients. Care must be used not to overly retract the incisors relative to the facial profile. A major advantage is the ability to avoid patient cooperation problems and negative forward movement of the lower arch. Contrary to some “experts” no negative TMJ problems are associated with this treatment.
Ø Noncooperative molar distilizing appliances e.g., Pendulum, Wilson. Reciprocal mesial movement of the anterior teeth however usually limits the effectiveness of these appliances. Although promoted as not needing patient cooperation, Class II elastics are often required to back up these appliances.
Ø Often the best treatment is a camouflaged, compensated dentition with the upper anteriors slightly lingual and the mandibular anteriors slightly flared.
Ø For some severe problems ideal overjet cannot be obtained without using techniques that the patient rejects (surgery, extractions, braces, etc.) For these patients a Hollywood Smile (straight teeth but an uncorrected “bite”) can be offered
Ø Notwithstanding the Align Technologies computer animation showing overjet correction, it is extremely difficult to correct significant Class II malalignment with Invisalign.
Ø Perhaps one of the most exciting new advances in orthodontics may be the use of implants or temporary anchorage devices (TAD’s) that provide anchorage without the negative reciprocal mesial movements.

Bottom Line: how do we treat these patients? We weigh all the factors including the severity of the problem, likely patient cooperation, predictability of correction, facial esthetics (and on and on ….). In the end there are many ways of achieving a good correction and it is our job to come up with the best way for each individual patient. Not only should different techniques be used for the different types of Class II’s but, since there are positive and negative effects for each technique, different approaches are possible for the same problem.
To say that upper premolars should never be removed or that headgears are no longer needed is to take valuable tools out of the orthodontist’s armamentarium. And when the only alternative for full correction is full braces and a surgical procedure what’s wrong with giving a patient (after going over all of the alternatives) straight teeth and less than “ideal” bite? Sure there are negatives to various approaches but sometimes the alternatives are no better or even worse. It is the orthodontist’s responsibility to evaluate the pros and cons of the various techniques and, in consultation with the patient, parents and dentist come up with the best option for each patient... and this is what we try to do!

Third Molars

2007-10-02T13:16:00.001-07:00

Our first topic: “post hoc ergo propter hoc” or why third molars don’t cause orthodontic relapse.

The orthodontic literature is pretty clear that, in general, third molars do not cause orthodontic relapse or crowding. The reason why this is such a strongly held belief is that it is almost “normal” for the anterior teeth (especially the lower incisors) to crowd up in the late teens or early twenties. This happens whether or not the patient had braces (or even wisdom teeth) and is probably related to late mandibular growth and a flattening of the anterior facial profile. Since this is the same time that the wisdom teeth “try” to erupt it is very easy to confuse cause and coincidence. The Latin phrase that speaks to this logical fallacy is: “post hoc ergo propter hoc” which translates “after this therefore because of this”.
This is not to say that there are not good reasons to extract the third molars, but that these reasons have more to do with whether the third molars can erupt into a self cleaning area or whether they will stay impacted and resorb roots or cause cysts. These are questions best left to the long-term evaluation of the patient’s general dentist.
The dental arches do not expand much as a child ages but they do get longer with the first molars erupting distal to the primary teeth, the second molars farther distal and finally the third molars. Unfortunately most of the time growth is complete before sufficient room is created for the third molars.
It is often the case that even with additional room provided by premolar extractions and some mesial movement of the molars during space closure there is still insufficient room for the thirds. For this reason we cannot even “promise” a patient that extracting premolars is really a trade where we extract four easily removed teeth (premolars) to save four bigger and more difficult to remove teeth (third molars).
In some borderline cases surgical removal of the distal gingival tissue can allow the patient to keep the third molars clean.
Bottom line is that the dentist must make a decision when growth is complete if there sufficient room for the third molars to come in to a self-cleaning area. If there is room, but the third molars are not coming in correctly, then a decision has to be made whether it is worth it to place partial orthodontic appliances to get the third molar aligned or just extract them as “unnecessary” teeth. Of course it is always hard to get a 20 year old to consent to further orthodontic treatment but sometimes they would rather do some ortho than some oral surgery!
As the above items point out there is nothing extra that the orthodontist can add to the decision as to whether to extract the third molars except in those rare cases when there is sufficient room but the third molars are erupting incorrectly and the patient would consent to additional orthodontic treatment.

Hope this helps!

Sincerely,

Robert M. Waxler, D.M.D., M.S.
Jeffrey T. Cavanaugh, D.D.S.
For Century Orthodontics

P.S.

Topics for our next letters may include:
Retention
Class III growth
Class II correction techniques (pros and cons)
Clear Appliance Therapy (CAT) appliances (Invisalign and OrthoClear)
TMD
Extractions
Wires and brackets

If you have any request please let us know (century@centuryorthodontics.com)

ORTHOHiddenTextDONOTDELETE

For dental professionals

2006-10-12T08:38:00.000-07:00

NOT ANOTHER NEWSLETTER

With all the dental magazines and journals in circulation we are inundated with information on every facet of dentistry. Sending out a “personal newsletter” to our colleagues with cut & paste articles from the orthodontic literature doesn’t really do it for us!

Since much of orthodontics is still not fully “evidenced based”, and treatments are often influenced by the prejudices (good and bad) of the practitioners, it is not surprising that different orthodontist often seem to give very different answers to the same problem (just ask a few: “how many months do they require full time retainer wear after braces?”). For what’s its worth, we would like to use these letters to give you our philosophies of treatment to help you with your referrals and to understanding the care of our mutual patients.

Our first topic: “post hoc ergo propter hoc” or why third molars don’t cause orthodontic relapse.

The orthodontic literature is pretty clear that, in general, third molars do not cause orthodontic relapse or crowding. The reason why this is such a strongly held belief is that it is almost “normal” for the anterior teeth (especially the lower incisors) to crowd up in the late teens or early twenties. This happens whether or not the patient had braces (or even wisdom teeth) and is probably related to late mandibular growth and a flattening of the anterior facial profile. Since this is the same time that the wisdom teeth “try” to erupt it is very easy to confuse cause and coincidence. The Latin phrase that speaks to this logical fallacy is: “post hoc ergo propter hoc” which translates “after this therefore because of this”.
This is not to say that there are not good reasons to extract the third molars, but that these reasons have more to do with whether the third molars can erupt into a self cleaning area or whether they will stay impacted and resorb roots or cause cysts. These are questions best left to the long-term evaluation of the patient’s general dentist.
The dental arches do not expand much as a child ages but they do get longer with the first molars erupting distal to the primary teeth, the second molars farther distal and finally the third molars. Unfortunately most of the time growth is complete before sufficient room is created for the third molars.
It is often the case that even with additional room provided by premolar extractions and some mesial movement of the molars during space closure there is still insufficient room for the thirds. For this reason we cannot even “promise” a patient that extracting premolars is really a trade where we extract four easily removed teeth (premolars) to save four bigger and more difficult to remove teeth (third molars).
In some borderline cases surgical removal of the distal gingival tissue can allow the patient to keep the third molars clean.
Bottom line is that the dentist must make a decision when growth is complete if there sufficient room for the third molars to come in to a self-cleaning area. If there is room, but the third molars are not coming in correctly, then a decision has to be made whether it is worth it to place partial orthodontic appliances to get the third molar aligned or just extract them as “unnecessary” teeth. Of course it is always hard to get a 20 year old to consent to further orthodontic treatment but sometimes they would rather do some ortho than some oral surgery!
As the above items point out there is nothing extra that the orthodontist can add to the decision as to whether to extract the third molars except in those rare cases when there is sufficient room but the third molars are erupting incorrectly and the patient would consent to additional orthodontic treatment.

Hope this helps!

Sincerely,

Robert M. Waxler, D.M.D., M.S.
Jeffrey T. Cavanaugh, D.D.S.
For Century Orthodontics

P.S.

Topics for our next letters may include:
Retention
Class III growth
Class II correction techniques (pros and cons)
Clear Appliance Therapy (CAT) appliances (Invisalign and OrthoClear)
TMD
Extractions
Wires and brackets

If you have any request please let us know (century@centuryorthodontics.com)

ORTHOHiddenTextDONOTDELETE