unilateral Loss of a mandibular primary canine

Cause: caries or trauma

It is relatively uncommon to lose a mandibular primary canine due to caries or trauma, but it does happen from time to time. First, confirm that the primary canine is not being lost due to root resorption caused by ectopic eruption of permanent lateral incisors. If it is, this is a strong indicator of an underlying tooth size-arch length discrepancy (TSALD) which will change your management approach.

When a primary canine is lost in the mandible due to caries or trauma, it’s often desirable to space maintain to prevent unfavourable changes in arch dimensions. Management options are as follows:

    • Pros: may prevent midline shift, maintain arch symmetry, and allow for spontaneous resolution of crowding.

    • Cons: may enhance deleterious dimensional changes (collapse) of the arch.

    • Pros: prevent midline shift, maintain arch symmetry, maintain overall arch dimensions.

    • Cons: incisors may not be in favourable position for space maintenance, may be of limited value if extraction of permanent teeth will be needed in future to treat the TSALD.

    • Pros: as for (2), but balancing extraction may allow for spontaneous improvement of arch symmetry before LLA is placed to maintain arch dimensions.

    • Cons: as for (2).

    • Pros: minimize current costs and burden of care, may need extraction of permanent teeth in the future anyway.

    • Cons: May miss opportunity to space maintain, complicating future orthodontic treatment.

The decision will be heavily influenced by how you expect the case to be managed orthodontically in the future. 

  • Cases that will be treated non-extraction are more likely to benefit from intervention.

  • Cases that will require extraction of permanent teeth anyway may be best left alone for now (or treated as a serial extraction case).

Since management of this situation can be challenging and very patient specific, Dr. Jeff likes to air on the side of caution and refer to a specialist to create a comprehensive long-term plan when uncertain.