February is Dental Health Month, and what better way to show off a great set of teeth than with a wide smile? As humans we display common emotions like fear, anxiety, embarrassment and happiness through facial expressions, but we're not the only creatures capable of communicating moods without audible expression. Whether or not animals can actually "smile" has been up for debate for decades, but recently there has been some consensus that animals can indeed express how they're feeling through facial gestures.

Whatver you believe about animals and their feelings, the truth is that smiles on animals can be contagious. We found some of the best smiles the animal kingdom has to offer.

Zebras aren't thought of as the most facially expressive animals in the world, but this one wasn't afraid to show off a toothy grin for the camera.

Wild boars are known for their tusks, which are actually continuously growing teeth. They are vital for the health and safety of mature male and female boars alike. Typically, a male boar's tusks grow to be about 2.5 inches, but they grow up to 5 inches in some cases.

It's hard to mistake a bottlenose dolphin with that naturally upturned mouth. Physically they already look like they're smiling, but they're known for their playful behavior as well. Bottlenose dolphins can have between 18 to 28 cone-shaped teeth on each side of the jaw.

Chimpanzees are the closest relatives we humans have to the animal kingdom, and the resemblance certainly shows when they're happy. Chimps have similar dental structure as well with 32 teeth able to grind and cut just like human teeth. 

It's no wonder why Kristen Bell loves sloths so much. The smile on this baby sloth is enough to make anyone a sloth lover!

Few things can get a dog smiling faster than playing with his favorite toy — and it's pretty sure to get a smile back from his owner too.

Cockatoos, like other birds and parrots, may not have teeth, but it's important their beaks stay in good condition. Healthy birds will grind their beaks themselves, but sometimes they need a little extra help from us. An avian veterinarian will know if your bird is in need of a beak trim or extra beak-grinding accessories for your bird's cage. 

Kittens can be pretty mischievous, especially with that sneaky little grin they never seem to grow out of. They are by nature cute as can be, but the kitten smiling in the picture here couldn't be much cuter in our book.

Good dental health is an important factor for all horse owners to consider, as a horse's teeth are in many ways his lifeline. Whether he's whinnying, yawning or actually smiling, it's good practice to keep an eye on his teeth whenever the opportunity presents itself. 

Some would say Bulldogs have a face only a mother could love, but that's what makes them adorable. Combine that wide face with a big toothy smile and you've got a recipe for a melted heart. 

There's nothing like the toothy grin of a camel to brighten your day. Equipped with 34 sharp teeth, camels have to constantly chew cud like cattle, which means they can't wear a bit and bridle like horses when ridden. Instead, riders attach reins to a halter with a ring placed below the nose to guide them.