Site icon College of General Dentistry

Orthodontics in general dentistry – an unknown, unknown

Specialist orthodontist Professor Ross Hobson, discusses the complexity and importance of correct assessment and diagnosis of a patient before orthodontic treatment.

Why is Orthodontics important? And why is it important to correctly assess and diagnose the malocclusion before starting out on restorative or orthodontic treatment?

Firstly, it is important to understand that tooth movement occurs throughout life as a natural phenomenon. This mainly affects the lower arch resulting in a reducing arch length, collapse of the inter-canine width and crowding of the anteriors. This is a combination of mesial drift (the process that is thought to allow for interproximal wear occurring due to an abrasive stone age diet), facial growth occurring throughout life and soft tissue age changes (reduction in muscle tone and flexibility). The combined effect on the dentition is similar to blocking the end of a travellator, in that the forward moving teeth crowd up against the ‘barrier’ of the lips.

This crowding results in reducing the ‘Envelope of Function’, a concept first described by Pete Dawson, and ‘Pathway Wear’, described by Greggory Kinzer. The combination of continued tooth movement, the dynamics of the Envelope of Function and Pathway Wear, means that a patient’s anterior tooth position changes with time but the patient’s pattern of function or parafunctional movements do not. 

The lower teeth moving forward at a greater rate than the uppers is a natural phenomenon and the result of this constricts the Envelope of Function resulting in the wear of upper and lower incisal edges. This can lead to chipping of the incisal edges and continued wear occurring.

Too commonly there is failure to correctly diagnose the underlying orthodontic problem. The uppers are restored but the undiagnosed occlusal forces result in failure of the composite. Then porcelain is used and the lower anteriors begin a destructive cycle of incisal wear, with significant loss of lower incisor crown height and overeruption of the lower incisors. Eventually, becoming an extremely difficult problem to correct.

Then there are skeletal and dental malocclusions that can further complicate restorative care eg increased overbites due to skeletal growth, anterior open bites and significant anterior-posterior and transverse malocclusions. Some may be accepted and ‘ignored’ but many will influence the outcome and success of care, dooming some to predictable failure.

In orthodontics there are many ways of achieving a good treatment outcome, fixed, lingual and aligners all can do ‘The job’. However, in some circumstances one appliance type may be better suited to achieving the desired outcome. So, it is important to know the advantages and limitations of the different types of appliances. BUT you must be aware that there is no such thing as a ‘magic’ brace that moves teeth faster or can avoid some implications of orthodontic treatment eg need for extractions.  What is essential is understanding the treatment options available to the individual patient and the advantages and disadvantages of the treatment options – including no treatment.

Understanding orthodontics, the identification and cause of malocclusion and knowledge of how it can be corrected or managed as part of general dental care is essential for all dental practitioners.   Some may be encouraged to go on to learn basic orthodontic techniques to achieve small changes that can be life changing for practitioners and their patients, and others will wish to further develop their orthodontic skills to much higher levels.  This is the basis of the College’s postgraduate training and qualification in primary care orthodontics – to build on current knowledge and skills, with progressive development with skilled mentoring.

Whatever level of skill you wish to attain, it is all based around a sound knowledge of assessment and diagnosis, without identifying a problem, it is an unknown, unknown….


Professor Ross Hobson Leads the College’s Postgraduate Diploma in Primary Care Orthodontics and is hosting a three-part CGDent webinar series exploring the possibilities and limitations of orthodontic treatment with fixed braces. The live webinars are free to view for all dental professionals and College members have free access to the recordings and CPD.

The next intake on the CGDent Postgraduate Diploma in Primary Care Orthodontics will start in April 2023.

Sign up to our monthly newsletter

Exit mobile version