The T-Rex may have lips, according to researchers.

A new evidence suggests that dinosaurs may have lips. According to a research, theropod dino teeth are too well preserved to have been exposed in a fierce grin all day.

"When we see dinosaurs in popular culture, such as in the movie Jurassic Park, we see them depicted with big teeth sticking out of their mouths," says Dr. Robert Reisz from the University of Toronto said in a report by BBC UK.

It turns out that dinosaurs are not so ferocious like what most people think.

Bones of dinosaurs are the ones preserved today, so people have no idea about muscles and skin of dinosaurs would look like. With that, Reisz decided to study modern day reptilian predators such as the crocodile and monitor lizard in order to find clues.

Crocodiles are large aquatic reptiles. Their teeth stick out on the outside of their mouth, however, these are protected because they spend most of their time in the water.

Meanwhile, one of the land creatures, monitor lizards' teeth are covered by gums and scaly lips, thus prevent their teeth from drying out.

Reisz's study concluded that the teeth "were not exposed permanently, but covered by reptilian lips" just like lizards. Aside from checking the teeth, the team looked at tusks in modern mammals with modified and permanently exposed teeth. According to study's findings, the tusks have some enamel at its first form, but soon replaced by cementum.

Meanwhile, Danielle Default, a paleo-scientific illustrator, Tweeted an illustration of what T-rex may have looked like with lips.

"Robert Reisz giving us the tooth of the matter: dinosaurs had lips, and enamel is the key! Chew on that! #CSVP2016," Default wrote on Twitter.