Transversal Expansion and Self-Ligating Brackets: A CBCT Study
Paolo Cattaneo, L. Cevidanes, M. Treccani, A. Myrda, B. Melsen
Aarhus, Denmark
Aim: To perform 3D assessment of the transverse changes of the maxillary alveolar bone on patients treated with active and passive self-ligating brackets. Material and Methods: Pre- and post-treatment CBCT-scans of 50 patients were taken. 3D models were generated from the scans, were registered using the cranial base stable structures, and superimposed. Changes in basal alveolar bone and dental arches were evaluated using a 3D colored mapping. Results: Expansion happened mostly in the canine and more in the premolar region, and was achieved by buccal tipping. No transverse augmentation of basal bone could be detected. High variation and strong patient-related patterns of transversal expansion were observed.
There has been a lot of media buzz about Damon braces with claims that extractions are not required, and that bone is generated due to extremely light forces. There are also unsubstantiated claims about moving teeth faster. Most people don't want teeth taken out and want fast treatment. With ads showing Miss Seventeen wearing them, who wouldn't want a Damon orthodontist?
At Markham Centre Orthodontics, we strive to provide evidence-based treatment for your Unionville braces and Markham orthodontics. Despite the hype and buzz about this "revolutionary" technology, we want to be sure we are providing our patients with the best and healthy options possible. It is important to realise that it is the orthodontist, treatment planning, and diagnosis, that produce successful outcomes, not a particular product, be it Damon, Invisalign, or any other type of appliance.
A study has come out of the University of Oklahoma by Paventy to scientifically refute the claims by Damon users. They used cone beam technology, similar to that of CAT scans, to measure bone around the teeth after trying to correct severe crowding that Damon braces claim to be able to correct without extractions.
Here is the abstract:
Nonextraction Treatment Using the Damon System: A CBCT Evaluation
Anthony M. Paventy
University of Oklahoma
Objective: To evaluate facial bone changes using CBCT after arch development using the Damon System in nonextraction treatment of moderate to severe crowding.
Methods: 19 patients with clinical crowding of 5+ mm were treated following the Damon System. ACBCT scan was taken prior to bonding (T1) and again after arch development (T2). T1 data served as the internal control group.
Results: The maxillary 1st premolars, mandibular 1st and 2nd premolars and mandibular molars all showed significant facial bone height loss. Additionally, every maxillary tooth showed significant mean facial bone width loss. The same was true for the mandible
Conclusion: The Damon System effectively expanded both dental arches. However, facial bone did not correspondingly adapt after arch development was completed. In fact, facial bone decreased significantly in height and width for nearly all teeth measured.
What this means is that while teeth can be straightened when there is inadequate space, the supporting structures around the teeth can be weakened, leading to an increased likelihood of future gum and tooth mobility problems. The data is beginning to show that severe crowding and transverse expansion may not be best treated without extractions, expanders, or surgery, regardless of what appliance is being used.
Note that the use of self-ligation with proper treatment planning has produced many successful results. However, studies unequivocally show that they are no faster than traditional brackets, and that some brands may actually be more uncomfortable. The data presented at the AAO in Boston and AAO/AAP joint meeting in Orlando confirm that there may be no advantage of self-ligation over traditional brackets.
Orthodontics should be directed at creating healthy smiles that last a lifetime. There are times that it is healthier to remove teeth than to try and fight the natural balance of our bodies. Seek your own professional opinion regarding your own personal situation. Please call 905-477-7750 to schedule your complimentary evaluation for Richmond Hill braces, Scarborough Invisalign, and Markham orthodontics.
5 comments:
Interesting debate going on here and what we see are the naysayers jumping on any bit of “anti-Damon” information. If one realizes the limitations of CBCT for the type of studies we want to see here, i.e., assessing thin alveolar bone, and if you talk to oral and maxillofacial radiologists, like my friend David Hatcher and James Mah, they will re-affirm the limitations of CBCT. The emotionality of the “anti-Damonites” is rising in crescendo now with these few limited looks. If one is truly going to practice evidence based orthodontics, why not apply the same studies, Oklahoma and Melsen’s, to Invisalign, SureSmile, Conventional fixed appliances, etc. and look at what is going on there.
People need to sit down and think critically about what they are reading and look for example at the time points when images were taken, types of software used to analyze, monitors, voxel size, etc., etc,
Really now, does not one think that whatever they are doing with aligners, passive or active clip ligation, conventional ties, etc. really is going to be that different. There will be alveolar bone changes at T2 if the time point is just at the completion of treatment. Is not the purpose of retention to let bone “complete” its remodeling and mineralization during the 3-6 months following treatment.
What one needs to do is a complete RCT is measure all the above groups at T1, T2 and 2 or more years follow-up with similar protocols. Once you analyzed all groups would you then get a real idea of what is happening.
A word to the SureSmile group, your technique will be undergoing the same “emotional and physiologic” debates soon, so get your cases ready to be analyzed by some enterprising graduate student.
I have only been doing the Damon PSL technique since 2000. It has continued to evolve with new wires and new brackets and anecdotally does seem to work. The critical thing with Damon or anything is that you have to work hard at excellence. Excellence begins with diagnosis, with bonding positions, etc. etc.
I started my graduate training in 1975 when the Andrews Straight Wire Appliance was just introduced. Good grief, you should have heard the emotional dissection of that technique that was going to destroy orthodontics because we would not have to bend wire. I have two graduate students looking at our conventional appliance and PSL appliance cases and guess what we can’t really measure bone levels with our conventional films, and even thought I had the Galileos CBCT (very small voxel size) and now ICAT, still can’t get adequate enough assessment of bone levels. Damon used Helical CTs on his patients and some were imaged up to 2 years or so out of treatment. NO COMPARISON WITH CT’s AND CBCT, plain and simple.
In the early 80’s did we as a profession, do the same studies on the introduction of elastomerics to see the positive and negative impacts on tooth movement. We did not have CBCT just conventional radiographs and what have we seen, look at the JADA article last year that politely slams orthodontics for causing bone loss from their literature reviews.
Lets get honest and lets get serious here. We have new technology that will enlighten us in the next few years, we have the ongoing controversies about this and that, but suffice it say, there are so many variables that it behooves, you the clinician, to look thoroughly at how these studies have been conducted, how the treatment mechanics were carried out, etc.
Enjoy these ortho studies, debate, argue, but BE CRITICAL AND THINK. Just don’t take the conclusion at face value.
Terry Carlyle
Great Post Dr. Tam!
Hi there, I have been doing LOTS of research on Damon braces and am trying to decide which direction to go with my own ortho treatment. I came across this blog and wanted to know if you have changed your mind at all about Damon and self-ligating brackets since you posted this blog in 2009.
There's nothing really wrong about Damon braces if the doctor knows how to use them. However, there is still not any significant data to show there is a true benefit to their use. At the end of the day, the brace is just a tool to make teeth straight. The skill of the doctor is going to determine the benefits of your results. Imagine Serena Williams playing tennis with my racket and me playing with hers. I'm pretty sure the racket would not be the reason she beats me. Treat orthodontics using any type of technique as just that, a technique, rather than a commodity.
Post a Comment