This issue is devoted to veterinary dentistry
This Month's Note:
A broken jaw sounds more like a surgical problem than a dental problem to most people. In the past this was usually how broken jaws were viewed by the veterinary profession, as well. It is necessary to fix a pet's jaw securely as quickly as possible. There just isn't any good way to explain to a pet that it can't use its jaw in a normal fashion Veterinarians have used all kinds of procedures to repair jaw fractures with reasonable success, including bone pins, bone plates and other specialized bone repair techniques.
More recently there has been a great deal of progress in repairing fractured jaws using wire supports anchored to teeth along with dental epoxies to manufacture splints that can be fixed securely to the teeth to hold them in place. This provides better alignment and in many cases better fixation of the fracture site. If your pet has a fractured jaw it is probably better to think of the injury as a dental emergency and to seek the help of a veterinary dentist rather than a veterinary surgeon.
February is Dental Health Month for pets, but like lots of other things, you can't fully appreciate that unless you are thinking ahead a little. So this month I'd like to try to explain the most important dental health needs of pets at various stages of life. I am hoping that by doing this it will become a little more clear why dental care is important for pets and perhaps also a little bit about why it is often neglected, despite its importance to your pet's overall health.
I am going to skip at home dental care in this issue except for this mention. It really does help to learn to brush your pet's teeth. There is no question that it is helpful. There is also no question that most people aren't going to take the time to learn to do this and then to follow through and continue brushing their pet's teeth during its life time. I really admire my clients who do this but I don't expect it from my clients as a whole. Most of the veterinarians I know don't brush their own dog's teeth on a regular basis, including me. I do work to provide treats and toys that help in dental care and I clean my pet's teeth on a regular basis in the office but brushing them is something that just doesn't get done. It's a good goal and well worth the time if you are committed to your pet's care but you shouldn't feel guilty if you can't handle it.
Juvenile Dental Care
The first place to start when thinking about dental health is when the decision is made to pair a male and female dog for breeding purposes. This might seem a little early to some folks but a great many of the dental problems that I see in my practice are a direct result of choosing to breed dogs who have preexisting dental disorders that are most likely to be genetic in origin. If your dog or cat has a significant overbite or underbite and isn't from one of those breeds where this is the norm, then you should stop and think before choosing to pass that trait on to future generations of puppies and kittens. If your pet is missing canine teeth or has lymphocytic/plasmacytic or other immune mediated gum disease you have to consider these factors, as well. There are times when it is reasonable to breed a dog or cat who has a dental disorder to preserve other important traits but you should at least think this situation over carefully before proceeding with breeding.
After puppies and kittens are born it is a good idea to open their mouths and to check for cleft palates or obvious oral problems. In most cases you won't find any problems. If a cleft palate is present, as evidenced by a slit or hole in the roof of the mouth it is important to discuss this problem immediately with your vet. It is possible to raise puppies, or kittens with cleft palates successfully and to repair the disorder at appropriate times but it usually involves a lot of time and care on the part of the owner, as well as paying for surgical repair when the time comes.
Just like people, pets have deciduous teeth for a while when they are young which are replaced by permanent teeth as they age. Puppies and kittens are usually born with no visible teeth. Puppies will normally begin to have visible teeth at about 3 to 4 weeks of age, with the four canine teeth and the incisor teeth coming in first. By the time they are 6 to 8 weeks of age the entire set of deciduous teeth are usually present. Dogs usually have 28 deciduous teeth. Cats get their teeth a little earlier than dogs on the average but they still usually won't have visible teeth until they are about 3 weeks of age. Kittens usually have 26 deciduous teeth by the time they are 6 weeks old and all of the deciduous teeth are present.
It is not always important if a deciduous tooth is missing. There are times when the deciduous tooth won't form but the permanent tooth will come in on a normal schedule. It is possible in most cases to identify the bud of the permanent tooth on X-rays, if it is important to do so.
Some kittens and puppies who have poor bites, due to excessive length of the lower jaw or underdevelopment of the lower jaw can benefit from selective removal of the deciduous teeth to allow growth to occur more naturally in the jaw that is blocked from growth. Removing deciduous teeth that are catching on other teeth or catching on the palate can enable the shorter jaw to grow to a more normal length. It is usually best only to remove teeth that are actually contributing to the problem. If your pet has a bite problem and is young enough that bone growth is still possible it may be worthwhile to consult with a veterinary dental specialist to determine if selective removal of baby teeth could help your pet.
It is important to pay attention to the positioning of the lower deciduous canine teeth in puppies and kittens. It is very common to find that these teeth are situated more towards to the center line of the mouth than they should be. This is called a base narrow bite. This produces a situation in which the lower canine teeth touch the hard palate. In severe cases these teeth can cause injury to the hard palate which are painful for the pet and can lead to serious complications such as an oronasal fistula (open passage between the mouth and the nasal passages). In most cases it is possible to live with this problem when it affects the deciduous teeth but it is critical in these cases to watch carefully for the eruption of the permanent canine teeth. If there is any part of the permanent canine tooth visible and the deciduous canine tooth is still present in a patient with these base narrow canine teeth it is very important to have the deciduous canine tooth removed. Don't wait until the tooth is half in or even all the way in to deal with this problem. If you can see two teeth trying to occupy the same spot, one of them should be removed!
It is tempting to leave baby teeth alone when they are broken but it is usually a better idea to remove broken baby teeth to prevent infections around the tooth root that might affect the permanent teeth. It is not uncommon for puppies or kittens to fracture the deciduous canine teeth so it is worthwhile to look at these teeth once a week or so to make sure that they have not been damaged.
The permanent incisor teeth usually start to come in at about 14 to 16 weeks of age for kittens and 15 to 16 weeks of age for puppies. Some kittens have permanent incisor teeth as early as 12 weeks of age but this is not all that common. The permanent canine teeth, premolars and molars all usually appear at about 5 to 6 months of age for kittens and 5 to 7 months of age for puppies. If there are bite problems that didn't respond to earlier efforts or that appear as the permanent teeth erupt, this is the time to think about orthodontic procedures. There is usually no need to fix bite problems that are simply cosmetic. It is not ethical to fix these problems in a show dog unless it seems clear that the problem was not due to genetics. The optimal period for orthodontic manipulation of teeth is relatively short in a dog or cat due to the rapid growth phase that occurs in the first year of life but it is possible to have successful orthodontic procedures after this growth period, when necessary.
People sometimes take suggestions to consider orthodontic procedures unfairly. A sizable percentage of our clients simply ignore these suggestions on the premise that the dog or cat's bite isn't important enough to consider this type of procedure. In many cases that is true but we usually mention orthodontia in passing on those cases. When we make a strong argument for orthodontics we do it because we feel that the pet will be in pain or may have serious long term consequences due to the bite problems that are present. If your vet takes the time to discuss orthodontic procedures there is usually a good reason for doing so.
Early Adult Dental Care
Most of my clients assume that their pet's teeth will be fine when they are young. This is often a false assumption. While it is true that the onset of tartar formation doesn't occur in many pets until 1 to 2 years of age, it is equally true that many pets have tartar formation as early as a year of age. We have seen pets as young as two years of age with significant periodontal disease due to heavy calculus formation. It is important to examine your pet's teeth on a regular basis and to consider a professional tooth cleaning procedure if there is evidence of calculus formation on the teeth. It is almost certain that the overall health of pets would improve if once or twice yearly teeth cleaning procedures were the normal standard in veterinary medicine. Unfortunately, this is far from the situation that really exists. Most of my canine patients have enough plaque and tartar formation by the time they are two years of age to justify a professional teeth cleaning procedure under general anesthesia. We are more successful controlling tartar using hand scaling during office visits without anesthesia in cats but I don't know of many veterinarians who are comfortable doing this and most feel that they can't do a good job cleaning teeth in cats without general anesthesia.
Cats and dogs are different when it comes to anesthesia. Once in a while someone writes to me to inquire about a dog's death during a dental procedure. At least two or three times a year people write to tell me about deaths of cats that occur during dental procedures. This happens frequently enough that I really believe it is best to ask your vet specific questions about how teeth cleaning procedures are done in cats. It is not uncommon in veterinary medicine for teeth cleaning procedures to be done by veterinary technicians. There is no reason to worry over this, after all a dental hygienist usually cleans my teeth, not my dentist. There is reason to worry if the same technician is responsible for monitoring anesthesia during the procedure. At a minimum there should be two certified veterinary technicians participating in the teeth cleaning procedure, one to do the procedure and one to monitor the anesthesia. It is even better if there is a veterinarian dedicated to monitoring the anesthesia. It is easier to cause anesthetic complications in cats. The small size endotracheal tubes are prone to kinking. Inflation balloons on the tubes can easily be over inflated in cats, causing damage to the lining of the trachea. It is very easy to rest a forearm on the cat during a dental procedure and this can lead to unnecessary compression of the chest. This might not bother a medium size or large dog but it is hard on small dogs and most cats. If your veterinarian can't assure you that your cat will be monitored by a person in constant attendance during the anesthetic period it would be best to consider having the teeth cleaning procedure done at a veterinary hospital that can provide this level of care. Board certified veterinary dentists usually meet this standard of care during teeth cleaning procedures.
Cats have several significant dental problems that can occur during the young adult years. Cats are prone to feline odontoclastic resorption lesions (FORLs). These are lesions in which the tooth simply resorbs over time due to the inappropriate activity of a type of cell, the odontoclast, which normally helps in dissolving the roots of the baby teeth. Cats with these lesions initially have holes in their teeth that resemble caries lesions (cavities) in humans. The difference is that this is not a bacterial infection and can not be easily controlled by fillings. Odontoclastic lesions almost certainly are painful. There is good reason to remove affected teeth. In the past it was unclear whether it was necessary to remove the tooth roots since there was a chance they would resorb on their own. It is much easier to remove the visible crown of the tooth and enough root to allow suturing the gum over the extraction site than to remove the entire root of a tooth that is dissolving. The increased use of X-ray machines in dentistry in pets has provided more information on the debate over how to remove affected teeth. If the tooth roots are actively dissolving (resorbing) on the X-rays then it isn't necessary to remove the entire root. Leaving the root tip may save a great deal of time and money. If the tooth roots are not affected by the resorption process going on then it is best to remove them. It can be quite difficult to remove these teeth due to the damaged crowns and intact roots. If your veterinarian is not willing to remove affected teeth you can ask for referral to a veterinary dental specialist.
Cats get a form of oral inflammation that is referred to as lymphocytic/plasmacytic gingivitis (sometimes stomatitis). This causes severe inflammation of the gums and affected cats appear to be very uncomfortable. This condition occurs in dogs but less commonly than in cats. Lymphocytic/plasmacytic gingivitis will sometimes respond to antibiotic and/or anti-inflammatory medications. When it won't respond to medication the next best treatment is removal of teeth in affected areas. This can often mean removing all the teeth except the front incisors and canine teeth. This sounds very radical but cats with lymphocytic/plasmacytic gingivitis are often so uncomfortable that it is a huge relief to them when the teeth are removed. It is very important to get the entire root of all teeth in affected areas so this is another time that it can be better to seek the help of a board certified veterinary dentist.
Dogs have a tendency to chew on objects that are very hard. Chewing on rocks, oyster shells, hard chew toys and real bones can lead to slab fractures of the upper 4th premolars. These are the big teeth in back of the mouth. When these teeth are broken by chewing the outer surface of enamel is usually sheared off the side of the tooth. In some cases the tooth is cracked in other directions, as well. Sometimes these teeth will do well for a very long time after a slab fracture of the enamel occurs but this may just be luck. The fractures often open up a pathway to the pulp cavity or deep into the root structure and the tooth is eventually lost. It is reasonable to remove these teeth at the time a tooth fracture is noted but we usually wait to see how much they will bother the dog before doing that. When this particular tooth has a root abscess there is often a swelling just below the eye on the side of the face. If this occurs the tooth should be removed as soon as possible.
Middle Age
At least 80% of dogs and cats over 5 to 6 years of age have significant periodontal disease. If their dental needs are not taken care of they will lose teeth unnecessarily. In addition, they are often in significant pain.
It is a little scary to contemplate general anesthesia on a regular basis but most dogs and cats would benefit greatly from an annual teeth cleaning procedure. There are exceptions. I see some dogs and cats who have no tartar and no other significant dental lesions during their entire lifetimes. Unfortunately, these lucky pets account for only 15% or so of the dog and cat population so the odds aren't all that good that your pet is one of them. There is always risk when using general anesthesia. Most commonly in pets when there is an anesthetic problem it results in death of the patient. You can help to lower the risk, though. Ask your vet if a certified veterinary technician or a veterinarian will be present to monitor anesthesia other than the person cleaning the teeth. If not, ask for referral to a veterinary dental specialist who will provide that level of service.
Fractures of the teeth are frequently seen in middle aged pets. In dogs the canine teeth and the upper fourth premolars are most commonly affected. The fourth premolar on each side is the widest of the teeth and is the fourth tooth back from the canine teeth. These teeth are generally damaged from chewing on hard objects. The enamel breaks off the outer surface of the tooth and this eventually leads to tooth root infections in many dogs. In cats the canine teeth break most frequently. This is a common problem in cats who hunt or fight a lot. Cats have very superficial pulp cavities and it doesn't take a major tooth fracture to lead to problems. It is a good idea to have fractured teeth X-rayed to determine if the fracture has exposed the pulp cavity and to take measures to prevent problems if so. It is possible to resolve problems by removing the tooth or by performing a root canal and sealing the tooth.
Some middle aged pets have teeth that are worn down. This occurs most often in pets who chew hard objects regularly, carry a tennis ball frequently or chew on their skin and hair frequently. If the teeth wear down slowly they can usually repair themselves as the process goes along and it is usually not necessary to think about procedures such as root canals even though the teeth are much flatter than when the dog or cat was younger.
Older pets
If your dog hasn't had regular dental care by the time it is 8 or 9 years of age it is a good bet that there are several teeth that need to be extracted. A cat older than 10 to 12 years of age is often in similar shape.
Your pet will feel better if these teeth are removed, in almost all cases. It is not at all uncommon in veterinary practices for clients to say their pet feels better than it has in years after extractions of teeth that are too far gone to save, combined with a professional teeth cleaning procedure for the remaining teeth.
In many cases teeth have gotten this bad because the pet owner is afraid of anesthesia and has not allowed regular dental care due to this fear. When the teeth get into really bad shape this fear of anesthesia doesn't go away. The pet is often in significant discomfort due to the teeth and this eventually becomes obvious to the pet owner. Their fear of anesthesia is often overcome by the realization that their pet may actually die from complications of dental disease if they don't consent to anesthesia. There is no reason to wait this long!
In most cases only a few teeth need to be removed even in older pets whose dental needs have been neglected. If this is not the case and many teeth or even all teeth need to be removed don't despair. Dogs and cats can get by with no teeth at all. Feeding a soft consistency food, such as canned dog or cat food, is all that is necessary to enable them to eat. Many pets without teeth are content continuing to eat dry pet foods. The bottom line is that bad teeth cause discomfort in almost all pets and severe pain in some pets. Stop the suffering and have necessary tooth extractions performed.
Teeth with visible roots and teeth that move when they are touched usually need to be removed. Heavy tartar accumulation is often present when tooth support structures in the jaw are breaking down but heavy tartar alone does not necessarily signal the need to remove a tooth. It is surprising how often teeth with heavy tartar are in relatively good shape after they are cleaned up.
If upper canine teeth must be removed there is a chance that a permanent hole between the oral cavity and the nasal passages will form where the tooth was removed. This occurs most commonly when a passage is already present due to the damage to the tooth's socket and the surrounding bone. This is most common in dogs with long noses, especially dachshunds, but it can occur in any breed. When the bone is very weak it is hard to avoid this complication when extracting upper canine teeth but it is a good goal. Cats who have significant problems with the upper canine teeth often have a hard swelling around the base of the canine tooth. In dogs it is more common for the canine tooth to be slightly lose when it needs to be removed.
When lower canine teeth must be removed it is a good idea to ask your vet if he or she has a lot of experience removing lower canine teeth. These teeth occupy a very large portion of the width of the lower jaw where they develop and it is possible to fracture the jaw while attempting to remove the lower canine. This also happens sometimes when the lower third or fourth premolars must be extracted and there is significant weakening of the jaw bone around the tooth. When big teeth on the lower jaw of cats and small dogs must be removed it is important to be cautious during the tooth removal to avoid injuring the lower jaw. If your pet has a problem with one of these teeth it may be worthwhile to consider asking for referral to a veterinary dentist.
There is very little additional risk in anesthetizing older patients. I am not sure where the myth that age is a major factor in anesthetic risk came from. In our practice experience the greatest anesthetic risk occurs the first time a pet is anesthetized and young pets have accounted for the great majority of all anesthetic related deaths in our practice. If your pet lives to old age it is a good indication that his or her body works well and will be able to handle anesthesia. Take the necessary precautions, such as pre-anesthetic lab work, that are necessary to make sure you are comfortable allowing an anesthetic procedure to be performed but don't let fear of some effect of age on anesthesia keep you from taking care of your older pet's dental needs.
There is a lot of controversy over how much dental disease affects overall health. There are lots of veterinarians who feel strongly that persistent dental disease contributes to heart disease, kidney disease and other systemic illness. Despite these strong feelings it has been hard to prove conclusively that dental disease has a clear impact on systemic health. It seems likely that this is the case and some recent studies come close to proving a link. Even without this extra incentive it is pretty clear that dental care is beneficial for the quality of life of dogs and cats.
Final thoughts
I am not sure why dental care seems to be the area that causes most of my clients to make comments about how far veterinarians have gone in pushing for "human" medical care for pets. I get more comments about how dental care is one step too far in pet care than almost anything else, though. For a long time I had some of these feelings, myself. I thought that pushing for good dental care was just pushing many of my clients too hard. As I have continued to practice and watched my patients over time I have come to a much different conclusion, though.
We choose to own pets. We provide the circumstances which allow animals that would probably live 2 to 3 years on the average "in the wild" to live much longer. We must accept the responsibility for caring for the conditions that occur as the result of our desire to have pet companions and to keep them for as long as possible. Dental disease causes significant discomfort at a minimum and outright pain in many pets. It probably contributes to systemic illness in at least some pets. It should not be viewed as optional or luxury care. Dental care is a basic essential that deserves much more attention than it currently gets from pet owners and veterinarians.
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The opinions expressed in this newsletter are those of Michael Richards, DVM., author.
Copyright 2005, TierCom, Inc.