July 2005
Dr Gerhard Steenkamp

A one year-old Dachshund is presented for vaccination. While performing a thorough clinical examination you see the following.

A What is your diagnosis?

B What treatment is advisable and when?

C Which breeds commonly present with these developmental problems?


Picture DSC 03878



Memorandum

A Persistent (retained) deciduous maxillary canine tooth. In this case persistent is the more correct term to use as the deciduous tooth has fully erupted but has not exfoliated. Strictly-speaking retained would refer to an unerupted tooth.

B Extraction of the persistent canine tooth is indicated. In most of these cases the persistence of the tooth is directly linked to the failure of the resorption of the root. Although the popular believe is that the development of the permanent tooth will stimulate the resorption of the root of the deciduous tooth, it has been shown in research that root resorption is also a process that the body would perform only during certain periods of time. Research has shown that resorption will still take place at the right time, even if the permanent toothbud has been removed.

Dogs and cats shed their deciduous teeth from about 16 weeks of age up till about 22 weeks of age. This means that patients at the age of 24 weeks (6 months) should not have any deciduous teeth. If at this age the teeth are persistent and there is no mobility, surgical extraction of the tooth and the whole root should be performed. Root remnants of these teeth will not undergo resorption, but will cause the full range of complications as in permanent teeth.

Should the tooth be mobile at this stage, I will advise the client to daily mobilize the tooth more by digital manipulation. Mobility is a sign that root resorption has taken place, even if just partially. Often the crown may stay attached at the gingival margin and needs very little encouragement to exfoliate. Should the tooth not exfoliate in 2 weeks time, extraction is needed.

C Toy breeds are more at risk; breeds like Yorkshire terriers, Pomeranians, Maltese terriers, Shi Tzu, Pekingese etc.