Birte Melsen: How has the spectrum of orthodontics changed over the past decades?

The Journal of Orthodontics of this month has invited Prof. DrOdont, B.Melsen from the university of Aarhus Denmark, to write an article about orthodontics today.


This article is in a form of a lecture. Dr. Melsen talks about almost every aspect of orthodontics today.


From "fast food orthodontics", self-ligating, "intelligent wires and brackets", "no bending orthodontics" to individualized treatments for adults with periodontal and degenerative diseases. TADs and digital orthodontics (digital casts, computerized treatment planing) are a field of interest for the future, and push the limits of orthodontics according to Prof Melsen.


Along the caustic comments about the industry, the marketing of new wires and brackets, it is reminded to everyone, that orthodontics is all about treatment planning and goals orientation. There is no cook book in orthodontics, and this article is certainly worth of your time.

Facial Reconstruction of an 11 year old female resident of Athens 430 BC, Angle Orthodontist, Jan 2011.

A relatively recent excavation at the site of Keramikos which was a burial ground for the ancient city of Athens, there was an interesting discovery that saw the light of dawn.
The skull at the picture on the left is of a female speculated to be around the age of 11 years. The skull dates back to 430 BC, when during the Peloponnessian war and the siege of Spartans to Athens, there was a large plague, that killed several athenians.
The skull provides clues of that period concerning the plague. Also suprisingly well preserved is the dentition of this young girl. All teeth of the upper and lower jaw are completelly intact and as such this archeological finding is of major interest to the dental scientific world.


The girl was given the name Myrtis by the archeologists.


At http://www.myrtis.gr/ you can find a lot of information also in english about this finding, but please note that the website is still under construction.


Two publications among others that are of orthodontic relevance are made at the Angle Orthodontist journal. Both of them are with a free access pdf file for anyone interested to download. Corresponding author of both articles is Dr Pagrigorakis MJ.

• Dental status and orthodontic treatment needs of an 11-year-old female resident of Athens, 430 BC, AngO Jan 2008
• Facial reconstruction of an 11-year-old female resident of 430 BC Athens. AngO Jan 2011

Design and Management of Twin Blocks

William Clark published recently an article at the British Journal of Orthodontics.


Design and Management of Twin Blocks: Reflections After 30 Years of Clinical Use


As the abstract reads:
There is an amount of misconceptions concerning the design of the Twin Block appliance. Those misconceptions might lead to poor compliance and poor treatment results and discourage some clinicians from the use of the appliance.


Small note: This post will not go into the principle and the basics of the Twin Block therapy as it's aim is to discuss the common mistakes when constructing the appliance. As such it is mend for readers with prior clinical experience using the appliance. 




Height of Occlusal Blocks


The height of the occlusal blocks should be enough to overcome the freeway space and not allow the patient to retrude the mandible when at rest. However constructing very high blocks would give other undesired complications.


Patient has to be able to close the lips without major strain, to be able to incise and chew posteriorly without difficulty, not to affect his/her speech, and not compromise the aesthetics when worn. These will ensure compliance and full time wear of the appliance which is the goal for the Twin Block therapy.


What is commonly used among clinicians is the rule of 2mm inter-incisal clearance, that will give a 5-6mm opening at the first premolar region. However this is not the case for all starting malocclusions, and that is one of the most common mistakes.

Mandibular deviation and canted maxillary occlusal plane treated with miniscrews and intraoral vertical ramus osteotomy

In the American Journal of Orthodontics and Dentofacial Orthopedics of December 2009, there is an interesting suggestion of treating patients with mandibular deviation (unilateral mandibular displacement) and canted maxillary occlusal plane.


The traditional method of choice would be, a BSSO and setback of the mandible with rotation on the z axis, followed with a 3-piece LeForte I on the maxilla with differentiated intrusion to correct the cant of the upper jaw. 
However the authors suggest a less invasive approach with an intraoral vertical ramus osteotomy and setback-rotation on the mandible, and an approach with miniscrews and intrusion on the maxilla to correct the canting on the upper.

Case Report, Class II, Dental Subdivision.

• Patient female, age 13 years, 
• with a full distal on the left side and full neutral on the right. 
• Overjet 6mm, Overbite 4mm
• Lower midline 4mm off to the left, from the facial midline, 
• Upper midline on. 

(asymmetry on the lower jaw, dental class II, subdivision)

Class II div 2 Deep Bite, Where is the Limit

Patient is 46 years old with a severe Skeletal class II div 2, with extremelly retroclined incisors as you can see from the above pictures.

With patients like this a question arises as to where is the limit is biomechanic and biologically wise. The aim in this case is to intrude and torque those four front teeth with the minimum overjet-proclination possible, unlocking the bite and giving room to the patient to protrude her dorsally forced mandible to a more relaxed position.