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Orthodontics referrals

Orthodontics outpatients is now a Directly Bookable Service (DBS) via e-Referral.

The orthodontic department will see any referral for diagnosis, advice and treatment planning.

Patients can only be accepted for treatment if they fall within grades 4 or 5 of the Index of Treatment Need (IOTN). A small number from Grade 3 patients are accepted for registrar training.

IOTN Grade 3: moderate treatment need

  • Increased overjet greater than 3.5mm but less than or equal to 6mm with incompetent lips.
  • Reverse overjet greater than 1mm but less than or equal to 3.5mm.
  • Anterior or posterior crossbites with greater than 1mm but less than or equal to 2mm discrepancy between retruded contact position and intercuspal position.
  • Displacement of teeth greater than 2mm but less than or equal to 4mm.
  • Lateral or anterior open bite greater than 2mm but less than or equal to 4mm.
  • Increased or complete overbite without gingival or palatal trauma.

IOTN Grade 4: great treatment need

  • Increased overjet greater than 6mm but less than or equal to 9mm.
  • Reverse overjet greater than 3.5mm with no masticatory or speech difficulties.
  • Severe displacements of teeth greater than 4mm.
  • Extreme lateral or anterior openbites greater than 4mm.
  • Increased and complete overbite with gingival or palatal trauma.
  • Less extensive hypodontia requiring pre-restorative orthodontics or orthodontic space closure.
  • Posterior lingual crossbite with no functional occlusal contact in one or more buccal segments.
  • Reverse overjet greater than 1mm but less than 5mm with recorded masticatory or speech difficulties.
  • Partially erupted teeth tipped and impacted against the other teeth.

IOTN Grade 5: very great treatment need

  • Increased overjet greater than 9mm.
  • Extensive hypodontia with restorative implications.
  • Impeded eruption of teeth due to crowding, displacement, the presence of supernumerary teeth, retained deciduous teeth and any pathological cause.
  • Reverse overjet greater than 5mm with reported masticatory and speech difficulties.
  • Defects of cleft lip and palate.
  • Submerged deciduous teeth.