Why choose a specialist? “Functional orthodontics” “Dentofacial orthopaedics”

Why is this page necessary?

Metal braces and plastic plates have been used to move teeth for nearly 100 years. The technology is now so good that amazing changes are possible. No matter how much your teeth stick out, are spaced or crooked, your teeth can be straightened to give you an even more attractive smile, strengthen your self-esteem, and improve the image you present to others.

Straightening teeth is a complicated procedure. As a patient, you need to commit considerable time and money. In return you should expect precise results based on thorough training based on the best scientific evidence available from an accredited teaching institution (such as a major university), proven technical expertise and extensive professional experience.

Who is best qualified to provide the treatment you require? This page explains who’s who in the teeth straightening industry and will help you make an educated choice about treatment for you, your child, or your teenager.

First you need to understand that there are three categories of tooth-straighteners;

  • General dentists. All dentists receive about 100 hours of orthodontic training in their basic course, usually as part of a class of about 50 students that teach them how to carry out simple treatments although many choose not to do so because even “simple” treatments can unexpectedly become quite complex. General dentists are trained to correct simple problems with the way your teeth fit together (“the bite”). They generally restrict themselves to the use of removable plastic plates.
  • “Functional Orthodontists”. General dentists who have recently appeared to fill a market niche. They have often attended several weekend courses usually given by speakers presenting material well to one side of mainstream orthodontic thought. They typically use one type of treatment – “functional appliances” (bulky removable plastic devices – like a gum shield). Sometimes they finish cases with fixed metal braces. They are comparatively under-trained, have never presented themselves for review by an accredited teaching institution, characteristically have very limited experience and usually apply the same treatment modality to all cases. They tend to use impressive sounding jargon like “Growth Modification”, “Dentofacial Orthopaedics” and “Chirodontics” to describe treatments for which there is no valid and reliable scientific evidence.
  • Orthodontists. General dentists who have undertaken 2-3 years of advanced study at an accredited teaching institution (usually a major university) and are subsequently registered by the New Zealand Dental Council as specialists. As well as the 100 hours of training received during the basic course to become a general dentist they have successfully undertaken approximately 3000 hours of extra training, much of it conducted on a one to one basis. They are trained in all aspects of orthodontics, so they can treat problems according to an individual’s specific needs. They mostly use fixed metal braces, small plastic plates, and sometimes functional appliances.

The state of confusion

If you talk to an orthodontist and then a general dentist who offers more than just simple orthodontic treatments you may find that you receive quite different advice. The main issue is usually contrived to be whether or not healthy teeth should be taken out as part of orthodontic treatment to relieve crowding and/or increase anchorage? Although the correct answer has been known for decades, this is a somewhat emotional question that is still discussed possibly because of the obvious appeal that “non-extraction” therapies have to children and parents. A second issue is cost.

Functional orthodontists say,

  • Tooth extraction is rarely needed. No matter how crowded your teeth are, functional appliances can predictably and reliably expand the jawbones to accommodate all the teeth. Moreover, because this expansion has been achieved functionally, the expansion so achieved will remain stable for the rest of the patient’s life.
  • Functional appliances can “stimulate” jaws to grow more than they otherwise would have. A small lower jaw can be made to “catch-up” to an upper jaw that sticks out. A narrow upper jaw can be widened to improve breathing through the nose.
  • Crooked teeth can cause back problems which can in turn be corrected by “special cervico-cranio-mandibular” functional appliances or “Chirodontics”.
  • The extraction of premolar teeth always adversely affects the patient’s profile and can cause problems in the jaw-joints.

Registered orthodontists say

  • Much of the evidence which functional orthodontists use to promote their work has been investigated scientifically and rejected.
  • Functional appliances do not produce any effect that cannot be achieved with conventional braces. Conventional braces are much more efficient at detailing the positions of individual teeth than functional appliances .
  • It is sometimes necessary to extract teeth in severely crowded mouths to improve long-term stability or where space is required. For instance, to allow front teeth which stick out to be moved back.
  • Sometimes, NOT extracting teeth can lead to their loss from lack of bone support after expansion anyway.
  • Functional appliances cannot enlarge jaws to any clinically useful extent. Any increase in bone-size due to functional appliance treatment is very small, extremely unpredictable and will be eventually lost.
  • Extractions do not affect a patient’s profile adversely or cause problems in jaw-joints.
  • There is nothing wrong with functional appliance treatment as such. However, Orthodontists are highly selective about the cases they choose for such treatment and even then, about 70% will not achieve a satisfactory result without follow-up treatment using braces.
  • Treatment with functional appliances often has to be followed by treatment with braces to finish detailing the positions of individual teeth. This “double” treatment strategy usually results in a longer than average over-all treatment time for the patient and increased costs for parents. This is sometimes referred to as “double billing”.
  • There is no scientific evidence that supports the claim that functional appliances can influence back-pain
  • Conventional orthodontic opinion is based on the results of the most rigorous scientific research available. It thus meets the criterion that is required of all current medical treatments.

Research by Professor Lysle Johnson, then Chairman of the Department of Orthodontics at the University of Michigan, confirms that no serious effects to facial profile occur when teeth are extracted for orthodontic reasons. Nor do jaw joints suffer after extractions or braces. In fact Johnson is critical of the claims made by ‘Functional Orthodontists’ for market convenience. He said “the dire claims of the functional orthodontists are, at best, irrelevant to rational treatment planning, and at worst, a threat to the patient’s best interests” .

Recent research by Professor Michael Harkness, then Chairman of the Department of Orthodontics at the University of Otago, School of Dentistry has received world-wide attention for providing evidence that functional appliances do not increase growth of the lower jaw or result in more attractive facial profiles than conventional treatment with braces.

At last count there were over 23,393 articles about functional appliances and this number increases almost every time another issue of an orthodontic journal is published. In spite of this, the consensus of the specialty is that functional appliances do NOT offer patients any unique treatment benefits. This fact should, by itself, warn the parents of prospective patients that, if any of the claimed benefits are true, they are minute and transitory. The fact that “controversy” about the rationale of functional appliance therapy has existed for almost a century is a tribute to forces other than the application of scientific theory.

A final caution

Unfortunately, some providers of comprehensive orthodontic treatment make claims about their treatment procedures which sound attractive to both children and parents but which are not supported by scientific evidence. In particular, any claim that functional appliances are able to grow bone (“dento-facial orthopaedics”) to a clinically useful extent, the promise of treatment without the need for extractions, or attempts to cure back and shoulder aches, should be closely examined. Before you decide on the best course of treatment for yourself or your child, we think you should be aware of the facts.

Never agree to a program of comprehensive orthodontic treatment until you have confirmed that your treatment provider is a Registered Orthodontist. Even then, don’t be fooled by impressive certificates hanging on the wall which may well be totally irrelevant (GCAS – Graduate Certificate in Antarctic Studies for instance!), have been presented without examination by an un-recognised teaching institution, or worse, actually purchased by the advertiser! The most common abbreviations which you may find misleading are FNZDA, FICD and FACD. These “fellowships” denote membership of fraternity-style “colleges” and are not gained by examination.

On the other hand, any Masters degree from a university and any fellowship with an “R” in it denoting the term “Royal” such as FRACDS(Orth) will almost always have been gained by rigorous examination.

You may ask why it is that the New Zealand Dental Association and/or Dental Council of New Zealand have not acted against dentists spreading such potentially misleading information. That is a question that interests Sax Dearing also.

Finding a Registered Orthodontist

Most Registered Orthodontists are members of the New Zealand Association of Orthodontists and display this logo. Find a Registered Orthodontist near you by following this link to the New Zealand Association of Orthodontists Incorporated.