Abnormal Molar Development in Dogs

Dilacerated Mandibular First Molar in Dogs

The abnormal development and formation of the mandibular tooth, a molar located three teeth away from the midline of the jaw, is an oral health issue seen primarily in small breed dogs. The mandibular tooth is one of the first permanent teeth to develop a calcified crown, and one of the largest.

There is no gender or particular breed predilection, but small breed dogs are at risk due to the small amount of space in the jaw for the molar to grow into. Therefore, it is generally recommended that small breed dogs be given a full evaluation of the mandibular first molars as they are growing in. 

Symptoms and Types

The defect will appear at the neck of the madibular tooth, often with gum evidence that the gum is receding. There may even be extensive bone loss near the root and possible exposure of pulp inside of the tooh. X-rays may reveal discontinuity between the roots and crown and/or presence of pulpal stones in the canal or chamber of the tooth.

Causes

One of the possible causes for this developmental problem is a mechanical challenge (lack of space) in the mouths of small dogs that impede proper crown-root development. Invagination, a folding in of the enamel and/or cement of the tooth, sometimes occurs at the neck of the tooth, often with some degree of gingival recession (receding of gums) at the site.

Diagnosis

Your veterinarian will perform a thorough physical and oral exam on your dog, taking into account the background history of symptoms, if there have been any. Dens-in-dente, an anomaly of development resulting from the deepening of enamel into the dental papilla (the cells involved in the developing tooth), typically begins at the crown and often extends to the root before the calcification of the dental tissues takes place. Traumatic damage to the tooth, possibly from aggressive deciduous tooth (i.e., baby tooth) extraction, may be linked to a loss of dental integrity.

If your veterinarian finds that the tooth is too damaged to remain, an assessment of the remaining mandibular bone will be an important prior to an extraction attempt. The diagnostic evaluation will include taking a dental X-ray to evaluate the extent of the changes, particularly at the roots.

Treatment

Treatment for a dilacerated mandibular first molar will begin with the appropriate pre-operative antimicrobial and pain management therapy as it is indicated. In most cases, there will be indications of a non-vital pulp in the tooth, indicated by a wide canal, periapical (apex of the root), and bone loss. Extraction of the tooth is typically warranted. However, this should not be an aggressive procedure. Care should be taken, as osteolysis (the active resorption or dissolution of bone tissue) could result in a compromised mandible (lower jaw). Your veterinarian may consider the use of bone-promoting material after the extraction.

Although rare, an endodontic procedure may be attempted to save the tooth in cases with minimal pathological changes. There is also a possibility stones in the tooth chamber could complicate canal access.

Living and Management

Your veterinarian will prescribe pain medication to help mitigate the amount of pain your dog is in, and to facilitate normal eating. After the initial care, your veterinarian will want to recheck your dog’s teeth at least once to be sure there is no infection and that the healing is on schedule. The prognosis is guarded for maintaining the tooth. However, an affected dog's long term health is fair to good if a tooth extraction is performed.