Animal Dental Formulas

Instructor: Artem Cheprasov
In this lesson, you're going to learn about various animal dental formulas, what they tell us in terms of the arrangement and types of teeth, as well as what they imply about the animal.

Animal Dental Formulas

If you have a pet dog or cat, try gently opening their mouth and looking inside. Just don't stick your hand in there! After taking a quick look, wash your hands and then look inside your own mouth. Do you see a difference? If you have a pet horse or cow you'd see an even bigger difference.

Some animals have different types of teeth and configurations to their teeth. This lesson is going to go over the dental formulas and arrangements of adult dogs, cats, cattle, and sheep as well as what they imply.

Major Types & Functions Of Animal Teeth

Before we do this, let's get some basic stuff out of the way. To start off, we'll just go over the major types of teeth these animals have in general.

First, there are the incisors, abbreviated in dental formulas as 'I'. The incisors are the teeth right in the very front of your mouth. They help take a bite out of food such as when you bite into an apple. Animals use incisor for cutting into something or for grooming.

Next, there are the canine teeth, abbreviated as 'C'. You don't have to be a dog (canine) to have them. Those are the sharp teeth next to your incisors that make you look like a vampire if they're especially prominent. Animals use incisors to puncture and tear.

Lying next to the canine teeth are the premolars, abbreviated as 'P'. Animals use premolars to shear whatever is in their mouth, namely food. And located next to the premolars, at the back of the mouth are the molars, abbreviated as 'M'. The molars are used to crush whatever is in an animal's mouth.

When we refer to an animal's maxillary teeth, we are talking about the ones located 'on top', or the ones embedded into the upper jaw. When we refer to an animal's mandibular teeth, we are talking about the 'bottom teeth', the ones embedded into the lower jaw.

That was the basic gist of things you need to know for now as there are some nuances to all of what you've just learned but they're beyond this lesson's scope.

Formulas & Arrangement Basics

With that out of the way, we can now focus on understanding how animal dental formulas are expressed in general and what they indicate about the basic configuration or arrangement of the teeth inside the mouth.

Let's just use one dental formula in this section to keep things simple. Here it is:

2 (I3/I3, C1/C1, P4/P4, M2/M3)

Let's break this down. The '2' in front of this dental formula tells us we have to multiply the number of teeth expressed by the dental formula by two in order to figure out how many total teeth this animal is supposed to have.

Next, we see 'I3/I3'. You already know that 'I' refers to incisors. So, this part of the dental formula is telling us how many incisors the animals has. 'I3/I3' is expressed as a ratio. The numerator, or top number, refers to the number of maxillary incisors the animal has on ONE side of the mouth. The denominator, or bottom number, refers to the number of mandibular incisors the animal has on ONE side of the mouth. This is why we multiply everything by two! Animals have two sides to their mouth after all.

And so the same idea goes for the canines, premolars, and molars. Note how in this animal's case 'M2/M3' tells us the animal has two maxillary molars on one side of the face and three mandibular molars on the same side of the face.

In total this animal has 6 incisors, 2 canines, 8 premolars, and 5 molars on EACH side of the face. 2 x (6+2+8+5) = 42. This animal should have 42 teeth if all is normal.

Specific Formulas

Here are the dental formulas for the four animals we chose to compare in this study. Remember, these are the dental formulas for the adult animal as deciduous dentition (baby teeth number and arrangement) can vary. In other words, these dental formulas refer to the animal's permanent dentition:

  • Dogs: 2 (I3/I3, C1/1, P4/P4, M2/M3)
  • Cats: 2 (I3/I3, C1/C1, P3/P2, M1/M1)
  • Cattle: 2 (I0/I3, C0/C1, P3/P3, M3/M3)
  • Sheep: 2 (I0/I3, C0/C1, P3/P3, M3/M3)


So what can we glean from these dental formulas alone? Well, a few things, some of which we'll cover. First look at the dental formulas like this:

To unlock this lesson you must be a Study.com Member.
Create your account

Register for a free trial

Are you a student or a teacher?
I am a teacher

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back

Earning College Credit

Did you know… We have over 95 college courses that prepare you to earn credit by exam that is accepted by over 2,000 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Create an account to start this course today
Try it free for 5 days!
Create An Account