Throughout our professional lives, at university or beyond, we will be lucky to evade this question: “Will I need braces?”, be it from a self-conscious teen or a worried parent. What they are really asking is: “will I/my child be given braces free on the NHS?”. How do we answer this? And how do we answer this objectively rather than subjectively? This article is a brief overview of the IOTN system used by the NHS.
Now, we know that orthodontics is a long process, that involves a lot of money, of which is not something the NHS has in particular abundance. So it is – unfortunately- not possible to provide every child orthodontic treatment, especially to those with only mild malocclusions.
With this in mind, the NHS uses a system to prioritise the cases that would benefit most from orthodontics. This system is the IOTN – Index of Orthodontic Treatment Need.
What is the IOTN?
The IOTN is a measure for the necessity of orthodontic treatment for any child under the age of 18. By using this scale, it is possible to decide objectively whether a certain case is severe enough to warrant funding from the limited resources of the NHS.
The accurate use of the IOTN requires specialist training, and the general dental practitioner can use this as a guide to those that require referrals to a specialist.
The IOTN comprises two parts.
- The Dental Health Component
- The Aesthetic Component.
Dental Health Component
The dental health component is the measure of any discrepancies in occlusion and gives them a grade from 1-5, where 5 is most severe.
This is a table of the Dental Health Component, Using the MOCDO acronym to further prioritise different forms of malocclusion.
Grade 1 is almost perfection,
Grade 2 is for minor irregularities such as:
- slightly protruding upper front teeth
- slightly irregular teeth
- minor reversals of the normal relationship of upper and lower teeth which do not interfere with normal function.
Grade 3 is for greater irregularities which normally do not need treatment for health reasons:
- upper front teeth that protrude less than 4 mm more than normal
- reversals of the normal relationship of upper teeth which only interfere with normal function to a minor degree; by less that 2 mm.
- irregularity of teeth which are less than 4 mm out of line
- open bites of less that 4 mm
- deep bites with no functional problems
Grade 4 is for more severe degrees of irregularity and these do require treatment for health reasons.
- upper front teeth that protrude more than 6 mm
- reversals of the normal relationship of upper teeth which interfere with normal function greater than 2 mm
- lower front teeth that protrude in front of the upper more than 3.5 mm
- irregularity of teeth which are more than 4 mm out of line
- less than the normal number of teeth (missing teeth) where gaps need to be closed
- open bites of more than 4 mm
- deep bites with functional problems
- more than the normal number of teeth (supernumerary teeth)
Grade 5 is for severe dental health problems
- when teeth cannot come into the mouth normally because of obstruction by crowding, additional teeth or any other cause.
- a large number of missing teeth.
- upper front teeth that protrude more than 9 mm
- lower front teeth that protrude in front of the upper more than 3.5 mm and where there are functional difficulties too
- cranio-facial anomalies such as cleft lip and palate.
The Aesthetic Component (AC).
It is recognised by the NHS that there are some cases where aesthetics overrule any absolute values in malocclusion. The Aesthetic Component is a scale of 10 photographs showing different levels of “dental attractiveness”. The photographs were arranged in order by a panel of lay persons. Gradings are given by the clinician matching the patient to any one of the photographs. This is shown in Figure 2.
In the NHS, the AC is used for border-line cases with Grade 3 DHC. If the case has a high AC score (usually above 6), NHS treatment is permissible.