Dental Disease - Guinea-Pig

Introduction

Dental disease is less common in guinea-pigs than in rabbits or chinchillas, but probably more common than in other rodents.

Several features of the normal dental anatomy in guinea-pigs are important to note:

The occlusal plane of the incisors is horizontal.

At rest, the mandible is held in a caudal position and the incisor teeth are out of occlusion.

The mandible is wider than the maxilla.

The cheek teeth tip in a buccal direction in the maxilla and in a lingual direction in the mandible.

The occlusal plane of the cheek teeth has a 30° angle.

The palatine shelf and dorsal border of the mandible converge rostrally.

The crowns of the cheek teeth are almost level with the gingiva.

Incisor Overgrowth

Primary incisor overgrowth is rare. When it occurs, it is usually secondary to cheek tooth overgrowth or facial trauma.

Cheek Tooth Overgrowth

This is the most common form of dental disease in guinea-pigs. It usually occurs due to inadequate provision of abrasive feed and inadequate cheek tooth wear, which leads to overgrowth.

An association has been found between cheek tooth overgrowth and vitamin C deficiency, which leads to collagen defects and tipping of the teeth.

Problems caused by cheek tooth overgrowth include:

Tongue entrapment by the mandibular cheek teeth

Lacerations of the buccal mucosa due to sharp dental points on the teeth

Overgrowth, abnormal wear patterns and malocclusion of the incisor teeth

Apical overgrowth of the cheek teeth with perforation of the alveolar bone

Clinical Signs

Common signs include: anorexia, salivation, moist cervical dermatitis, slanted or abnormal incisors

Animals do not usually show signs until the tongue is trapped and the disease is advanced.

Diagnosis

A thorough dental examination should be performed, firstly using an otoscope in the conscious guinea-pig, but also using sedation to gain a better view.

Endoscopes can be used in the anaesthetised animal, and may reveal an uneven occlusal surface and angulation of the teeth, sharp points and mucosal ulceration and food impaction.

Radiography and CT can be used to better evaluate the extent and seriousness of the process.

Treatment

Treatment is centred on restoring a normal occlusal plane to the teeth under general anaesthesia.

Unstable animals should be provided with supportive care before anaesthesia.

A high-speed drill should be used to trim the cheek teeth almost level with the mucosa, angled at a 30° angle. The mandibular teeth should be trimmed so that they do not entrap the tongue. Any dental spikes should be removed.

Incisor abnormalities should also be corrected.

Analgesics and assisted feeding are used post-operatively until the patient eats on its own.

This is a life-long condition and the guinea-pig should be re-examined every 2-3 months.

A diet high in grass and herbage should be given to provide adequate abrasion and encourage frequent chewing.

Vitamin C should be supplemented as scurvy may be a primary factor in dental disease due to the weakening of the periodontal ligament. Vitamin C supplementation is also generally beneficial in any sick guinea-pig.

As guinea-pigs are usually presented when the disease is advanced, prognosis is usually poor and the condition will be difficult to control even with regular dental care.

Dental Disease - Guinea-Pig Learning Resources
Flashcards Test your knowledge using flashcard type questions	Small Mammals Q&A 04

References

Mitchell, M. (2009) Manual of exotic pet practice Elsevier Health Sciences

Gorrel, C. (2004) Veterinary dentistry for the general practitioner Elsevier Health Sciences

Rosenthal, K. (2008) Rapid review of exotic animal medicine and husbandry Manson Publishing