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Getting
to know you
Dogs’ teeth are arranged in facing upper and lower arches. The
lower arch is narrower than the upper. The roots of the upper teeth
are embedded in the incisive bone (incisors) and maxillary bones.
The lower teeth roots embed in the mandible. The dog’s teeth and
jaws are specialized for grasping and consuming animal prey. The
four canine teeth are long and pointy and dig in to establish the
dog’s grip while the prey species weakens and expires. Behind the
canines are the cheek teeth - premolars and molars – which are
shorter and wider, with cutting edges to chew and grind the food.
The first lower molar and the fourth upper premolar are called
Carnassial teeth, and their shearing action is particularly
important for a flesh eating mammal. There is one more molar tooth
in each mandible than in the corresponding maxilla. The incisors are
separated from the canine teeth by a distinct gap. These small thin
teeth are used primarily for gnawing flesh from bone (or chewing at
itches). When the jaws are closed the incisors, fourth premolar and
molars meet the teeth of the opposite arch. The incisors come
together optimally in a scissor or < like configuration, although
a straight bite is acceptable in the breed. The first three
premolars normally fail to meet and the opening formed is called the
first premolar carrying space. In longer muzzled dogs spaces will
appear between teeth, and sometimes supernumerary (extra) teeth may
be present. Extra or missing teeth are not a fault in beardies.
Dogs have two sets of teeth during their lifetime.
There are 28 deciduous or baby teeth and 42 adult or permanent
teeth.
Dental formula permanent teeth
Usually puppies are not born with teeth, and they
start to erupt between 2 and 3 weeks of age, and they are usually
all in place by the time the puppy is 6 weeks old – although there
can be considerable variation. Puppies do not have molars. Puppy
teeth are softer and thinner than permanent teeth and needle sharp.
Disease and nutritional deficiency can cause permanent damage to
puppy tooth enamel. Distemper, hepatitis and leptospirosis can all
damage tooth enamel leaving it pitted and discolored. Certain
antibiotics, most notably tetracycline, can have the same effect
whether given to bitch or puppy. The puppy teeth start to loosen and
fall out between 12 and 14 weeks of age with the adult teeth coming
in from front to back. The puppy teeth are loosened by the pressure
of the much larger permanent teeth coming in from below except in
the case of the canines. Permanent canines erupt beside the puppy
ones and they can coexist for some time before the puppy teeth fall
out. Removal of the puppy teeth is normally not advisable as you can
damage the root and enamel of the permanent teeth in the process.
Teething puppies often have sore and swollen gums and will chew on
anything to relieve the pain. Cold can be helpful, so putting
appropriate chew toys in the fridge or freezer may be helpful.
Chewing will also help loosen the baby teeth and aid in normal jaw
development. Permanent teeth are usually all in between six and
seven months. Jaws grow independently of each other; usually the
upper jaw grows ahead of the lower. Owners should not rush for
orthodontia, or worry about the dog’s bite or lower canines
growing into the upper palate. These usually come right once both
jaws have completed their development.
Each tooth has a crown (the visible part of the
tooth) and one or more roots which embed in the jaw bone. The neck
of the tooth joins the root and crown. Incisors and canines have a
single root, as do the first pre-molars. The upper second and third
premolars have two roots each, and the fourth premolars and molars
have three roots each. The rest of the lower premolars and molars
each have two roots, except for the third molar which has just one.
Common Dental Problems
The most common dental problem in dogs is
periodontal disease. Plaque – a mixture of bacteria, food debris
and mucus forms a fine, white film on the teeth and gums. Eighty
percent of plaque is bacteria, and four hundred different species of
bacteria have been found in animal mouths. The plaque gets under the
gum line into the periodontal pockets – the spaces whose depth
dentists human and veterinary measure at the base of each tooth.
From there the bacteria erode the bone holding the teeth –
resorption. This causes the teeth to loosen. In the mouth itself,
the plaque mixes with saliva to form tartar, the yellowish brown
cement like substance that sticks to teeth. Tartar generally forms
faster in dogs than in humans. The tartar pushes on the gums causing
them to recede further from the teeth, and providing further
opportunity for the bacteria in the plaque to attack the bone, enter
the root canals causing endodontal disease – disease inside the
tooth. Bacteria can also enter the bloodstream causing systemic
disease – sore throats, but more seriously heart, kidney and other
problems. Gingivitis is superficial inflammation of the gums.
Without appropriate dental care though, it will progress to
periodontal disease.
The second most common dental problem for dogs is
tooth fracture. This is often the result of hard objects sliding off
the edge of the tooth. Fractures may expose tooth pulp, which
contains the nerves of the tooth, so they are painful; this also
exposes the interior of the tooth to invasion by bacteria –
further increasing the risk of endodontal disease.
Dogs are prone to all the dental problems humans
get. As well as those already mentioned these can include tooth root
abscess, tumors of the gums and teeth and cavities. Dogs are
however, far less likely to get cavities than are people. When they
do occur they are usually seen as black marks on the tooth close to
the gumline. They can be filled in many cases.
Prevention
It is important that from an early age your puppy
becomes used to you handling his mouth and teeth. With a young puppy
wrap a washrag or piece of gauze over your finger and rub it back
and forth over his teeth and gums. Do this once or twice a day, and
when he is tolerating it well (Hint: it’s usually easiest when he
is sleepy). You can take a soft child’s toothbrush and accustom
him to that.
Once the permanent teeth are present tooth
cleaning should begin in earnest. Eliminating plaque before it
becomes tartar is clearly a good idea, and this is best achieved
mechanically with a brush. Optimally, dog teeth should be brushed
every day, just like ours; failing that try to do it as often as
possible, at least twice a week.
It is important to use a dog toothpaste with
enzymes for added action against plaque. Avoid toothpastes with
baking soda, detergent and/or salt, as dogs swallow the paste and
don’t spit it out like humans. Fluoride is present in some pet
toothpastes to help control bacteria. The best toothbrush for a
beardie has a long handle with an angled head to make it easier to
get all the way to the back teeth. The bristles should be soft to
aid penetration between the teeth, and into the spaces below the gum
line. Some people prefer a finger brush that fits on the finger tip.
The bristles are usually somewhat larger than on a regular brush,
and less likely to do a good job of cleaning below the gumline.
Place the brush loaded with paste (if possible
work the paste down between the bristles before you begin) at an
angle of 45 o at the junction of tooth and gum. Move it in an oval
pattern working it between the teeth and under the gums about ten
times and covering three or four teeth, and then move to the next
area. Most plaque and tartar forms on the outside of the upper
teeth; and this is the area which should receive the bulk of your
attention. While dental diets and chews can help remove tartar and
plaque from the exposed areas of the teeth, only brushing will get
beneath the gum line. Your vet may also recommend the use of a
canine mouthwash to help kill bacteria and heal damage to the gums.
When you have finished brushing your dog’s teeth, get in the habit
of doing a quick visual inspection for fractures – especially of
the carnassial and canine teeth, discoloration of the teeth, and
narrowing of the necks of the teeth. Look for sticks and other
objects caught between his teeth or under his tongue. Regular tooth
cleaning will not only help prevent tooth problems but should leave
your dog’s breath smelling sweet, and make his kisses much more
enjoyable. If after cleaning there is still an off odor to your
dog’s mouth take him to your vet as it likely indicates systemic
disease elsewhere in his body.
Professional care
Even with regular hand cleaning, professional
dental prophylaxis is often necessary to keep your dog in the best
dental health. Dogs need to be anesthetized for this, and in order
for anesthesia to be safe you must run a complete blood count and
biochemical profile to ensure your dog is in good health. (If not
problems need to be addressed before dentistry can be performed.)
Under anesthesia the tartar will be scaled from the teeth above and
below the gumline using both hand and ultrasonic instruments. The
teeth are then polished to remove the microscopic grooves introduced
by scaling which could make it easier for tartar to stick to the
tooth. Fluoride will often be applied to the teeth to slow the
return of plaque and tartar. It is wise to have X-rays taken of your
dog’s mouth, just as you would of your own, to make sure that
there are no problems developing in the tooth roots and jaw bones.
While dental technicians may do teeth cleaning in some states, this
is a surgical procedure, and it is better if a veterinarian performs
both the cleaning and examination. More complex cases should be
referred to dental specialists, many of whom are board certified by
the American Veterinary Dental College (AVDC).
Sometimes though, less can be more. Periodontal
disease has been related to diseases throughout the body, but any
oral surgery will introduce bacteria into the blood stream. This is
why your dog should receive antibiotics before and after his tooth
cleaning. In humans though, evidence is mounting that saving teeth
at all costs is not a very wise choice. You cannot sterilize a dead
tooth and root canals – which are becoming increasingly popular in
dogs – are basically preserving a dead tooth in the mouth. They
serve as a source of bacteria, viruses and fungi as well as necrotic
break down products such as endotoxins, and other highly poisonous
substances – hydrogen sulfide products and methyl mercaptens.
These organisms and poisons can travel the body in the blood or
lymph, and also along nerve fibers and into the brain. Acute or
chronic septicemia, slow, progressive shrinking of normal tissue
within the organs, and its replacement with inactive fibrous tissue,
infections within the organs, and allergic and immune disorders can
all be triggered, see table below. Perhaps it is better to remove
dead teeth rather than trying to salvage them. Dogs are less vain
about their looks and provided there is a canine remaining on each
side of their face their tongues tend to stay in their mouths and
not loll out.
With regular care your dog should be able to keep
his teeth for life and that life can be long and healthy if we avoid
letting oral organisms enter the body to wreak their havoc there.
It’s amazing that we can gain so much from a few minutes well
spent with a tooth brush each day. What is sad is that so rarely do
we do so. We often read in these pages that a judge has found dirty
teeth on an otherwise beautifully groomed and turned out beardie,
and yet, poor dental care will have a far more profound and serious
effect on our dog’s health than any mat.
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