Ectopic canine – detailed

➤ Labial canine bulge not palpable by age 10

• The canine bulge is a prominence caused by the erupting permanent canines above the Cs.
• If it cannot be palpated on the labial alveolus by the age of 10, investigation for canine ectopia should be performed with radiographs.
• Lower canine bulges are not usually present, hence identification of lower canine ectopia should be performed on radiographs and signs of crowding or obstruction.
• Early identification of canine ectopia will allow the patient a chance of interceptive treatment with a specialist orthodontist or dentist.

➤ Early loss of deciduous canines or space

• Early loss of deciduous canines by permanent incisors erupting is a sign of severe crowding. Buccally ectopic canines or those which are tranposing with lateral incisors are associated with severe crowding cases (Peck et al. 1998, Becker 2015).
• Early extractions of deciduous canines can also lead to loss of space and dental midline deviation which may cause a lack of space for canine eruption.
• These cases require early management of their space loss to intercept the canine ectopia.

➤ Radiographic signs of canine ectopia

• A panoramic radiograph (OPG) is an ideal screening image for upper and lower canine ectopia. Often associated problems such as missing teeth, diminutive lateral incisor roots may be found.
• Ericson and Kurol 1987 defined sectors of canine ectopia for maxillary incisors on the OPG. See radiographic signs.
• Early identification of canine ectopia will allow the patient a chance of interceptive treatment with a specialist orthodontist or dentist.

➤ Over-retained deciduous canine or obstruction

• Obstructions to canine erupts, such as retained Cs, supernumeraries, adjacent roots or pathologies like cysts, can be detected on radiographs.
• Early identification of these obstructions will allow for spontaneous eruption of the permanent canines after removal of their obstructions.

➤ Damage to adjacent teeth and structures

• Panoramic radiographs, periapical radiographs or CBCTs are effective imaging techniques to determine root resorption of adjacent teeth.
• Damage to adjacent teeth by root resorption requires intervention of the canine ectopia.

➤ Crowding due to ectopic teeth

• Ectopic canines which erupt are often displaced out of the arch form and a sign of severe crowding. This can be a significant handicap to the patient and a strong indication for treatment.

➤ Aesthetic concerns of ectopic teeth

• Buccally ectopic and erupted canines often have a very visual prominence in the patient’s smile line.
• There may often also be a midline deviation and associated crowding.
• These factors are all indications for orthodontic treatment.

➤ Trauma to soft tissues

• Ectopic canines which erupt can cause localised trauma to surrounding alveolar mucosa, tongue or buccal mucosa on normal function. This can be a significant handicap to the patient and is an indication for treatment.