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NHS assessment criteria

If your child qualifies for treatment and is ready for treatment (i.e. have all adult teeth and do not need any teeth removed) then you will be placed on our waiting list. Once your child is ready for treatment, you will attend the practice for further scans and have the brace fitted. If your child does not qualify, we can still offer you treatment but this will be on a private basis.

The IOTN scale is split into two components: Dental Health and Aesthetic. To be eligible for free NHS treatment, the overall score must be 3.6 or higher. The first number relates to the Dental Health component and the second to the Aesthetic component.

Dental Health Component

Grade 1 – No treatment required

  1. Extremely minor malocclusions, including displacements less than 1 mm

Grade 2 – Little need

  1. Increased Overjet > 3.5 mm but <= 6 mm (with competent lips)
  2. Reverse overjet greater than 0 mm but <= 1mm
  3. Anterior or posterior crossbite with <= 1mm discrepancy between retruded contact position and intercuspal position
  4. Displacement of teeth > 1mm but <= 2mm
  5. Anterior or posterior open bite > 1mm but <= 2mm
  6. Increased overbite >= 3.5mm (without gingival contact)
  7. Pre normal or post normal occlusions with no other anomalies. Includes up to half a unit discrepancy

Grade 3 – Borderline need

  1. Increased overjet > 3.5 mm but <= 6 mm (incompetent lips)
  2. Reverse overjet greater than 1 mm but <= 3.5mm
  3. Anterior or posterior crossbites with >1mm but <= 2mm discrepancy between the retruded contact position and intercuspal position
  4. Displacement of teeth >2mm but <=4mm
  5. Lateral or anterior open bite > 2mm but <= 4mm
  6. Increased and incomplete overbite without gingival or palatal trauma

Grade 4 – Treatment required

  1. Increased overjet > 6mm but <= 9 mm
  2. Reverse overjet > 3.5 mm with no masticatory or speech difficulties
  3. Anterior or posterior crossbites with > 2 mm discrepancy between the retruded contact position and intercuspal position
  4. Severe displacements of teeth > 4
  5. Extreme lateral or anterior open bites > 4 mm
  6. Increased and complete overbite with gingival or palatal trauma
  7. Less extensive hypodontia requiring pre-restorative orthodontics or orthodontic space closure to obviate the need for a prosthesis
  8. Posterior lingual crossbite with no functional occlusal contact in one or more buccal segments
  9. Reverse overjet > 1 mm but < 3.5 mm with recorded masticatory and speech difficulties
  10. Partially erupted teeth, tipped and impacted against adjacent teeth
  11. Existing supernumerary teeth

Grade 5 – Treatment required

  1. Increased overjet > 9 mm
  2. Extensive hypodontia with restorative implications (more than one tooth missing in any quadrant requiring pre-restorative orthodontics)
  3. Impeded eruption of teeth (apart from 3rd molars) due to crowding, displacement, the presence of supernumerary teeth, retained deciduous teeth, and any pathological cause
  4. Reverse overjet > 3.5 mm with reported masticatory and speech difficulties
  5. Defects of cleft lip and palate
  6. Submerged deciduous teeth

Aesthetic Component

This is a ten-point scale, illustrated by a series of photographs which show the full range of grades through different levels of dental attractiveness. A rating is allocated for overall dental attractiveness, rather than specific similarities to the photographs.

The final value reflects the treatment need on the grounds of aesthetic impairment, and by implication the socio-psychological need for orthodontic treatment.

Patient testimonials

Absolutely incredible, at every appointment the orthodontists were lovely and the building has such a nice atmosphere. The results for my daughter were life changing!
I have recently finished having my Invisalign braces course. I am really pleased with the outcome and love to smile now. Trevor and his team give you a personal experience and I would recommend. Thank you!
Absolutely incredible, at every appointment the orthodontists were lovely and the building has such a nice atmosphere. The results for my daughter were life changing
Both my children had braces fitted and have now moved on to retainers. We are more than pleased with the outcome and the brilliant work done by the team at Cygnet.