The content of decorative rodents and rabbits is a widespread hobby at present. Most often, houses contain rats, Syrian and dwarf (Campbell and Dzungarian) hamsters, gerbils, guinea pigs, chinchillas, degu and a representative of the rabbit-like order.
According to the type of food, these animals are divided into two groups:
- omnivorous rodents - rats, hamsters, gerbils,
- herbivores - rabbits, guinea pigs, chinchillas and degus.
However, animals from these groups differ among themselves not only in the composition of the diet, but also in the anatomy and physiology of the teeth, above all, indigenous.
A feature of herbivorous rodents is the lifelong constant growth of the crown of all teeth, both incisors and molars. In omnivorous rodents, only incisors constantly grow, and indigenous ones have a stable crown length. Grinding of growing teeth is ensured primarily due to friction of the upper teeth against the lower ones (and not by eating solid food or special mineral stones). Self-sharpening of the incisors also occurs. Rodents have differences in dental formula, i.e. in simple terms, a different number of teeth in the mouth (in a rabbit - 28, in a pig and chinchilla - 20). Common to all rodents and rabbits is the presence in the oral cavity of the incisor of molars in the absence of fangs.
An important point in the normal digestive process in the oral cavity is occlusion - coincidence of chewing surfaces of opposing teeth (upper and lower). Small enough dislocation (displacement of the position to the side by a fraction of a millimeter) and the tooth growth process becomes redundant, which leads to a change in the crown (its elongation, malformation, the appearance of sharp edges and processes). Malocclusion develops.
Malocclusion - a disease caused by mismatch of the masticatory surfaces and leading to improper erasure of the teeth and the formation of protrusions on them, injuring the soft tissues of the oral cavity and the bone structures surrounding the tooth.
Directly malocclusion is precisely a violation of the correct grinding of teeth. However, the result of malocclusion is the development of other diseases and pathological conditions:
1. mucosal damage / ulceration in the oral cavity and tongue,
2. violation of the growth of tooth roots,
3. infection of the nasolacrimal canal, postorbital space, bone tissue, with the further development of purulent conjunctivitis, postorbital abscesses, abscesses of the lower jaw, osteomyelitis,
4. violation of the temporomandibular joint,
5. refusal of food, depletion, dehydration of the animal, the development of tympanum and / or atony of the gastrointestinal tract,
6. the threat of sepsis and death of the pet,
7. the development of secondary diseases outside the digestive tract - dermatitis, pododermatitis, rhinitis, balanoposthitis.
All these diseases are considered as a single process, and summarized in one name - dental syndrome or dental disease.
Reasons for the development of malocclusion:
- a genetic defect in the jaw apparatus,
- violation of the density of tooth tissue due to errors in feeding (violation of the exchange of calcium, phosphorus and vitamin D),
- traumatic malocclusion - the effects of trauma in the head,
- there is evidence that the majority of herbivorous rodents and rabbits older than 3-4 years have some form or stage of dental disease.
The most noticeable symptoms of dental disease for the owner:
- complete or partial refusal of food,
- rapidly progressing exhaustion,
- deterioration of the appearance of hair throughout the body, profuse hair loss,
- bending of the incisors in the oral cavity or growth outside the oral cavity,
- inflammation of the lips, gums, excessive salivation from the mouth,
- swelling (abscesses) in the lower jaw,
- the allocation of pus from the eyes (purulent conjunctivitis),
- lack of bowel movement.
Diagnosis of dental disease in a veterinary clinic includes:
1. collection of data on the animal (age, pregnancy, diet),
2. clinical examination,
3. Dental examination (examination of the oral cavity and molars) - the main stage of diagnosis, most often immediately accompanied by medical procedures (correction). It is carried out under general anesthesia.
4. X-ray examination.
Treatment of malocclusion / dental syndrome.
First of all, the doctor informs the owner that the problem of malocclusion is a lifelong one and will constantly require care and regular visits to the veterinary clinic.
The basis of malocclusion therapy is the control of the height of the tooth crown and the removal of the so-called “Tooth hooks” - malocclusion of molars. To carry out the correction, various dental equipment is used (drills, discs, rotary expanders, dental tables, etc.). This procedure should be carried out using anesthetics, mainly inhalation anesthesia (the safest option for anesthesia for rodents and rabbits). In the future, due to the constant growth of the changed teeth, the dental examination and correction will have to be repeated. The interval between procedures is usually from 2 weeks to 6 months. Treatments stop only after restoration of normal occlusion. And even in this case, regular preventive examinations are required every 6 months. More often, such procedures are carried out throughout the life of the animal.
Other options for the treatment of dental disease can be surgical treatment (opening) of abscesses, removal of incisors and / or molars, sanitation of the nasolacrimal canal, removal of the eyeball. These procedures are also carried out under general anesthesia and are accompanied by preoperative preparation and postoperative maintenance therapy.
The prognosis for dental disease depends on the causes and degree of violation of occlusion and the presence of secondary pathological processes (the presence of abscesses, the development of osteomyelitis, etc.).
In some cases, the correction of pathological tooth growth at an early stage allows for complete recovery. Most often, it provides an opportunity to extend life and improve its comfort.
The rehabilitation period after the correction may include:
- forced feeding until the restoration of self-eating,
- washing the oral cavity with antiseptic solutions,
- the use of anti-inflammatory drugs,
- antibiotic therapy (in the presence of a purulent process),
- the use of prokinetics (stimulants of intestinal motility),
- the use of corticosteroids,
- parenteral administration of fluid solutions (subcutaneous, intravenous, intraosseous injection / infusion) in a hospital setting.
Dental disease and malocclusion - a common problem of decorative herbivorous rodents and rabbits, requiring emergency (no later than 3 days after refusing food) diagnostics and treatment using special equipment (dental instruments, means of providing inhalation anesthesia) and taking into account (knowledge) the particular anatomy and physiology of domestic animals groups.
Kazakov Artem Arkadevich, veterinarian, kvn.
Veterinarian Semirotova Tatyana Sergeevna
A proper clinical history will provide an initial database. The next stage is a thorough clinical examination. If the veterinarian sees a weakened animal, then he must begin maintenance treatment before the end of all diagnostic measures. A thorough examination of the oral cavity is necessary. Examination of the oral cavity in a conscious animal is very difficult due to the small size of the animal, large diastema and limited aperture of the oral cavity. The exception is the Syrian hamster (Mesocricetusauratus), the large and elastic cheeks of which allow the mouth to be opened wide for a thorough examination and examination of the cheek pouches.
To visualize abnormalities in the oral cavity, a bright light source and magnification are required. For most animal species, an otoscope can be used as an oral endoscope. Most oral
disturbances can be detected in the animal in consciousness, but negative examination results cannot rule out problems with the teeth. Approximately 50% of visible oral disorders are missed with these examination methods. Immobilization with drugs facilitates the examination of the oral cavity, because in this condition, you can use the mouth and cheek expanders to improve the visibility of the oral cavity. A small dental mirror is also needed. The tongue and cheeks of these animals are very sensitive, so any irregularities in the teeth can irritate them. Periodontal probe (with the usual medical, but only shortened instrument) helps to identify periodontal disorders and tooth mobility. Caries and other diseases of the crowns are determined by conducting an acute dental probe on the surface of the teeth. If possible, a manual examination of the oral cavity should be performed. This is the most sensitive method for detecting surface irregularities. Well visible protrusions of the teeth indicate a progressive stage of the disease. Even under anesthesia, an experienced specialist may not notice up to 25% of the disorders that are later detected with necropsy. Table 2 shows the main violations encountered in the oral cavity.
|Table 2. The results of the examination of the oral cavity and dental arcade|
|Periodic dyeing of wool with saliva, erythema, alopecia and pyoderma |
Pain on palpation of the zygomatic process of the upper jaw
Swelling of the ventral surface of the lower jaw
Discharges from subconjunctival sacs and / or nasal cavity
Scars, ulcers, perforations and tears of the lips
Sealing and inflammation of the cheek pouches
Excessive growth, damage, dysplasia, deformation or absence of incisors
Gingivitis, periodontitis, pyorrhea of incisors
Ulceration of the mucous membrane of the tongue, cheeks, palate and lips
Fibrous scarring of the tissue of the cheeks and some areas of the tongue
Deep lacerations in the tongue and / or cheeks
Sharp protrusions on the cheek teeth (can be invisible - determined by palpation)
Excessive growth, damage, dysplasia, deformation, caries or lack of buccal teeth
Gingivitis, periodontitis, pyorrhea, getting food between the cheek teeth
Neoplasms or abscesses
Since the pathology of the dental roots and bones is not visible during a routine examination, an X-ray examination is indicated. For rabbits and large rodents, you can use on-screen shooting, such as screening, but when examining teeth you need non-screen and dental shooting. Pictures are examined under magnification. Common radiographic abnormalities are shown in table 3.
|Table 3. Disorders in the state of the tooth and jaw, determined by x-ray examination|
|Enhanced growth of crowns of incisors and / or buccal teeth |
Fractures of the teeth and jaw
Incorrect jaw closure
Relative prognathy of the lower jaw
Anomaly in the structure of the temporomandibular joint
Elongation and deformation of tooth roots
Apical perforation of the alveolar bone
X-ray tightness of the lacrimal canal
Destruction of the periodontal bone
Abscesses of dental roots
Muzzle abscesses, some retrobulbar abscesses
After the diagnosis of dental disorders, a prognosis should be made and appropriate treatment should be started. An important aspect of the treatment is the well-being of the animal. If the disease is in a progressive stage, then it is recommended to consider the issue of euthanasia. Most animals experience severe pain that can only be eliminated for a while. Cruelly prolong the torment in such animals. Some dental problems can be solved very easily, while others take time to successfully treat others. In any case, monitoring of relapses or other problems is necessary.
Broken incisors. Broken incisors are a common type of injury. Therapy can be divided into three stages. First, treat visible violations. Secondly, antibiotics and analgesics are prescribed. Then, after stabilization of the animal’s condition, the broken edges are aligned with a dental drill. Under anesthesia, naked pulp is treated by pulpectomy, and then calcium hydroxide cement is applied. It should be remembered that the teeth will begin to grind as soon as they reach a certain length, so it is important not to use solid or toxic restorative materials to treat these teeth. Teeth that are opposite must be trimmed to compensate for the lack of wear and restore their function. A diseased tooth may stop growing or begin to deform if periapical tissues are severely affected. There are two ways out of this situation - regular cutting or removal of a damaged tooth and its opposite.
Teeth cutting techniques. Traditionally, teeth cutting for rabbits and rodents is performed without anesthesia with claws or wire scissors. But this method is unacceptable for several reasons. Excessive force must be applied to the crown, which damages the periapical embryonic tissues and the periodontal ligament, which disrupts the subsequent growth of the tooth. Longitudinal cracks often appear in the tooth, which extend under the gum and expose the console cavity. The procedure is very painful, even if pulp exposure was avoided. A tooth will never find its natural form of a chisel. For accurate tooth trimming, you need a high-speed dental drill that cuts the tooth with minimal effort. Also, a thin drill on a low-speed drill is suitable for this purpose. The console cavity never extends to the height of the surfaces being joined, it only reaches the level of the gums. It is preferable to carry out this procedure under anesthesia or sedation, but pruning can be done without them, holding the animal with his hands. Under anesthesia, a low-speed drill can remove protrusions and adjacent planes in animals with a constant growth of buccal teeth. A common method for cutting buccal and rodent buccal teeth also damages periodontal tissues.
Abscesses. The causes of muzzle abscesses in rabbits and rodents are usually dental diseases, foreign bodies, or wounds after fights. To develop an operating plan, you need to perform x-rays. Surgical excision is the most preferred treatment. All pathways of infection should be followed before they begin. Wounds are usually left open for granulation. Relapses of abscesses should be expected unless the underlying cause is found and removed.
Removal. Preoperative radiography helps to identify the pathology of dental roots, which may complicate removal. With the defeat of brachyodontal teeth, extraction is usually simple. Using thin instruments, careful progressive elevation and luxation of the tooth are performed. If necessary, hypodermic needles can be used as tools. In rare cases, after the removal of brachyodontal teeth, the destruction of opposing teeth is observed. Removing gypsodontal teeth is no longer easy.Careful elevation is generally effective, then sectioning and tooth extraction in parts, especially if the root is very long, to remove it in one piece. An extraoral approach through the ventral part of the lower jaw is also used to remove the lower cheek teeth. A damaged tooth is lifted and then pushed into the oral cavity or removed through a surgical approach. Access to the upper cheek teeth can also be obtained through a buccotomy. This is a traumatic procedure and should be avoided whenever possible. After the removal of the hypsodontal teeth, the consequences of the operation should always be checked, because to prevent the unnecessary growth of the opposite teeth, they need a closing surface.
Removing incisors is also a simple procedure, if their anatomy is known exactly. Usually, radiography is needed to assess the length and morphology of the dental roots. The crowns need to be shortened (best with a high-speed drill) so that a rotary expander can be inserted. After the procedure (it is difficult to keep the mouth open after removing the incisors), the oral cavity is washed with a disinfectant solution. To remove the epithelial attachment of the gums to each incisor along the gingival sulcus, a scalpel No. 11 is used, the incision is continued as far as possible along the periodontal ligament. At this stage, with a small elevator, which is used to remove the teeth of cats, they take out a simple “peg” incisor in rabbits. The removal of these teeth first prevents their fractures when large incisors are removed. The fibers of the periodontal ligament are stretched and rotated by repeated injections of a special curved luxator or thin elevator laterally and medially to each incisor, in this position they are held for 20 seconds. After a few minutes, the tooth is removed. If the tooth is sufficiently loosened, it can be pulled out with your fingers or tweezers, applying a rotational force in the direction of removal. The extracted tooth is examined for its integrity and complete removal of pulp from the alveoli. Bleeding is usually minimal. If the integrity of the gums is broken, and the bleeding persists, then sutures are made from absorbable material, otherwise the gum will close across the recess. Antibiotics
prescribed only for alveolar infection. Usually the cause of the removal is the inconsistency of the incisors, so most animals quickly adapt to food without these teeth. Removing incisors is a great way to stop the growth of these teeth if the owner does not want to cut them. Most often, this situation is encountered in dwarf rabbits with congenital relative prognosis of the lower jaw.
These animals often have problems with their buccal teeth (roots and crowns) in addition to excessive growth of the incisors, so a thorough examination is needed before treatment.
Possible complications. Tooth extraction in rabbits and rodents must be carried out very carefully so as not to break the teeth or jaw. Iatrogenic fractures of the lower jaw are potentially the most serious complications that lead to insufficient closure of the buccal teeth. Since the incisors in rodents and rabbits grow constantly, with root fractures, the rest can continue to grow. According to her own experience, the author testifies that most often a small incisor peg breaks, but even its broken root is easy to pull out, unlike the long root of a large incisor. When discussing the procedure, the owner is usually advised to remove fragments of the root under anesthesia. After this, it is recommended to undergo a second examination in order to immediately detect tooth growth.
If the teeth are completely removed, they will not be able to grow again, especially the gypsodontal ones, but the author was informed of two cases of re-growth of the teeth after their complete removal. Probably, in these two cases, the removal was carried out so carefully that the periapical tissue was not damaged. To reduce this probability, the doctor should remove the pulp along the entire tooth. If this failed, then the pulp is removed with curved forceps.
Prevention of dental diseases is more important than their treatment. In the wild, the animal is in the natural environment and eats the appropriate food. Ensuring the right environment and diet is
the best way to prevent animal health. Most rodents spend most of their life nibbling on something. To prevent incorrect closure of the incisors, they need to provide material for nibbling. Conversely, rabbits do not need such material, since it is not peculiar to rabbit-like in the wild.
Rabbits and rodents are very picky about food. If they are given a choice, they will be the first to eat high-calorie foods. Other foods that contain maximum vitamins and minerals may remain uneaten, resulting in feed imbalances and deficiencies. In addition, the tasty food does not require enhanced chewing and is less abrasive than natural food. In animals with constantly growing teeth, this leads to excessive tooth growth and lengthening of the roots. Rodents and rabbits with gypsum teeth must be given less high-calorie food and plenty of grass to reduce the likelihood of developing a tooth disease. Staying in the sunlight also improves the structure of bones and teeth, because it activates the production of vitamin D, which contributes to the metabolism of calcium.