One of the most common dental procedures that is performed on our young pets is the removal of retained deciduous canine teeth. All of our pets have "baby" teeth, but only some of them need to have them removed.
What are they?
Dogs and cats, like ourselves, have two sets of teeth that develop during their lives. The first teeth that develop are the deciduous teeth - also known as "baby" teeth or "milk" teeth". These teeth are followed at some time by the permanent teeth, or "adult" teeth.
The deciduous teeth are little replicas of the adult teeth that will come along in the future. However due to the size of the young animal's mouth, there are not quite as many deciduous teeth in the mouth as there will be in the future. In fact the premolars get their name not from being in front of the molars, but because they have a pre-cursor, namely they have deciduous teeth (except premolar 1!). Molars do not have deciduous precursors.
As cute, and as sharp, as they are the deciduous teeth cannot remain functional for the whole of the animal's life, so they are shed and replaced by the permanent dentition. The adult teeth start off as tooth buds at the base of the deciduous teeth, and so develop right below the deciduous teeth. AS the permanent teeth start to erupt (emerge from the jaw) they induce resorption of the roots of the deciduous teeth. When this process is complete (performed by Odontoclasts - see FORLs) the remaining piece of the deciduous tooth falls out of the mouth..... in most cases.
What problems occur?
Some deciduous teeth for some reason don't undergo the proper root resorption required for their shedding. This will result in the deciduous teeth still being present with the permanent version of the tooth being erupted as well. This situation is a real problem for the young animal. The deciduous tooth is the one in the correct position. However to erupt, the adult tooth has had to emerge in an incorrect position. We commonly see this problem arise with the deciduous canine teeth.
Retained deciduous canine teeth.
The problems that occur are twofold:
- the two teeth are tightly jammed against each other, creating the perfect environment for accumulation of debris and increasing the likelihood of periodontal disease - often resulting in the loss of both teeth.
- the permanent tooth is in the wrong position so causing malocclusion problems.
These issues can be dealt with appropriately by extracting the deciduous tooth and leaving the permanent tooth.
Deciduous teeth also can be fractured. This results in the same issues as a fractured permanent tooth. However the complicating feature with a dead, infected deciduous tooth is that there is a developing permanent tooth at its base, right where the infection of the deciduous tooth is being discharged! Fractured deciduous teeth must be extracted.
Fractured deciduous with infection.
Small exposed pulp of the pictured tooth with infection. Seems innocuous.
For the best results the extraction of the retained deciduous tooth should occur as soon as it is apparent that it is not going to shed normally and the adult tooth is erupting. This means that if the deciduous tooth is not "wobbly" and any part of the corresponding adult tooth is visible, then the deciduous tooth is removed. It does not mean:
- remove the deciduous teeth before the adult tooth erupts
- remove the deciduous tooth once the adult tooth is fully erupted.
Extraction of the deciduous tooth is not always a straight forward procedure. It is vitally important that all of the deciduous tooth is extracted. This is because it is the root of the retained deciduous tooth that is causing the problem, not the visible crown. The adult tooth has erupted beside the root of the deciduous tooth to get to where it is (in the wrong position). So removal of all of the deciduous tooth will allow the adult tooth to move as it continues to erupt.
Retained deciduous canine.
Retained deciduous canine has been extracted.
Deciduous canine showing length of the root.
If performed properly and there is still movement of the adult tooth (ie: eruption) the adult tooth will preferentially move across into the space left by the now extracted deciduous tooth - the correct position.
If your pet has not lost their "baby" teeth and the adult teeth are present, they should have the retained deciduous teeth removed. This will ensure you give your pet the best possible chance at having a healthy pain free mouth.