Lingually Displaced (base narrow) Canines
Base narrow (lingually displaced) canines occur when the lower canines are deflected toward the midline and penetrate the hard palate.
Remove the palatal impingement either by extracting the mandibular canine(s), reducing the height of the offending teeth and restoring them to remain shorter, or moving the teeth to a functional position with orthodontic brackets and elastics or a bite plane.
Right lower canine tooth interfering with hard palate
Crown reduced and restored: lower canine
After crown reduction and restoration, interference is resolved