Malocclusion in Rabbits
(c) Gryph- if you repost this article, please post with a link back to my website.
Rabbits are born with only one set of teeth. Like rodents, rabbits have open-rooted teeth which continuously grow throughout their lives. However, rodents and rabbits (which are lagomorphs- a group of animals which includes rabbits, hares and pikas) differ in which teeth continuously grow. Rabbits have four easily visible incisors (front teeth), plus molars in the back for grinding and chewing, with a gap in between incisors and molars. Unlike rodents, lagomorphs have two small, tube-shaped incisors (called peg teeth) behind their larger upper incisors (making a total of six incisors). The top incisors should slightly overlap the bottom teeth. Incisors are used to grab and cut food, and molars are used to chew and grind food. Since rabbit teeth continuously grow (at a rate of about 1 cm each month with properly aligned teeth), the upper teeth must meet the lower teeth and all teeth must wear at the same rate to allow for proper wearing of the tooth surfaces to prevent overgrowth. A rabbit with perfectly aligned teeth can eat hay, pellets and other food easily by grinding the top and bottom teeth together. Because the back of the top teeth and the front of the bottom teeth are rather soft, as the rabbit chews its food, it grinds both sets of teeth down which keeps them in a comfortable eating position. If the teeth aren’t perfectly positioned, then improper tooth wear occurs and can result in the overgrowth of the incisors or molars.
Poor tooth growth can cause all sorts of problems. Overgrown points or sharp spikes that form on the edges of teeth can cut and damage the tongue, cheeks or gums. Overgrown lower molars can form a bridge over the tongue, trapping it. Overgrown molars can hit each other in the back of the mouth, thereby preventing the front of the mouth from closing completely- this can cause the incisors to not wear down properly. Overgrown molars can become impacted- like impacted wisdom teeth in people. All these issues can lead to pain when chewing, development of sores and abscesses in the mouth and sinus cavity, difficulty eating, problems grooming, and weight loss.
The most obvious symptom of malocclusion is overgrown teeth that you can see protruding from the mouth. Some other visible symptoms of malocclusion include:
Misshapen teeth will sometimes grow at an angle to each other, curl back into the mouth, curl sideways, or take on other problematic positions. With an unopposed incisor, tooth growth could be as much as 1 mm per day! Incisors are easily checked by the breeder- molars are more challenging. Quite often molar issues are the cause of an incisor problem.
Rabbit malocclusions are often caused by hereditary or genetic defect, or by injury or poor feeding practices. Dwarf breeds with small heads are more prone to hereditary malocclusions. Injuries can be caused by excessive pulling on the wire of their cage which eventually changes the alignment of the incisors, or by breaking a tooth. Fractured or broken teeth can result from trauma to the face such as a fall, or teeth catching on a cage. If incisor malocclusion is the only problem in young rabbits, it’s likely to be a genetic issue. Bacterial tooth root infections can also change the direction of tooth growth.
Malocclusions do not go away. Rabbits do not outgrow them. Rabbits with malocclusions- especially if their teeth are not able to be trimmed down- do not have a good quality of life. They often cannot chew properly, and also often have troubles grooming themselves (thereby creating a bigger risk for fur mites and uncomfortable mats). This issue can also be genetic and should be removed from any responsible breeding program. Incisors CAN sometimes be kept trimmed to assist with eating, but it’s an uncomfortable process for both rabbit and handler (trimming should take place at least every 4-9 weeks). Trimming teeth can easily cause a split or cracked tooth which can be susceptible to infection. Teeth can be removed by a veterinarian but that is an expensive process.
Poor tooth growth can cause all sorts of problems. Overgrown points or sharp spikes that form on the edges of teeth can cut and damage the tongue, cheeks or gums. Overgrown lower molars can form a bridge over the tongue, trapping it. Overgrown molars can hit each other in the back of the mouth, thereby preventing the front of the mouth from closing completely- this can cause the incisors to not wear down properly. Overgrown molars can become impacted- like impacted wisdom teeth in people. All these issues can lead to pain when chewing, development of sores and abscesses in the mouth and sinus cavity, difficulty eating, problems grooming, and weight loss.
The most obvious symptom of malocclusion is overgrown teeth that you can see protruding from the mouth. Some other visible symptoms of malocclusion include:
- Drooling or saliva or food buildup under the chi, near the lips and on the inside of the front legs
- Swollen jaw (which can indicate an abscess)
- Lump on the outer cheek, under the eye
- Lump on or under the lower jaw (can start out small but grow bigger quickly)
- Mouth, cheek, chin, jaw and sinus abscesses
- Pawing at the mouth
- Fur pulling
- Poor grooming habits
- Inability to eat
- Eye and/or nasal discharge
- Sneezing
- Increased thirst
- Weight loss and/or decreased appetite
- Reluctance to eat hard food
- Bad breath/odor
Misshapen teeth will sometimes grow at an angle to each other, curl back into the mouth, curl sideways, or take on other problematic positions. With an unopposed incisor, tooth growth could be as much as 1 mm per day! Incisors are easily checked by the breeder- molars are more challenging. Quite often molar issues are the cause of an incisor problem.
Rabbit malocclusions are often caused by hereditary or genetic defect, or by injury or poor feeding practices. Dwarf breeds with small heads are more prone to hereditary malocclusions. Injuries can be caused by excessive pulling on the wire of their cage which eventually changes the alignment of the incisors, or by breaking a tooth. Fractured or broken teeth can result from trauma to the face such as a fall, or teeth catching on a cage. If incisor malocclusion is the only problem in young rabbits, it’s likely to be a genetic issue. Bacterial tooth root infections can also change the direction of tooth growth.
Malocclusions do not go away. Rabbits do not outgrow them. Rabbits with malocclusions- especially if their teeth are not able to be trimmed down- do not have a good quality of life. They often cannot chew properly, and also often have troubles grooming themselves (thereby creating a bigger risk for fur mites and uncomfortable mats). This issue can also be genetic and should be removed from any responsible breeding program. Incisors CAN sometimes be kept trimmed to assist with eating, but it’s an uncomfortable process for both rabbit and handler (trimming should take place at least every 4-9 weeks). Trimming teeth can easily cause a split or cracked tooth which can be susceptible to infection. Teeth can be removed by a veterinarian but that is an expensive process.
