According to Shar-Pei breeders in China, the muzzle of traditional Shar-Pei can be generalized into two types: The “bone mouth,” and the “meat mouth.” As they see it, any extra padding on top of the dog’s muzzle isn’t a good traditional specimen. These breeders prefer a “bone mouthed” or a “roof tile” mouthed dog, so called because the smooth curved surface on top of the muzzle resembles a roof tile. The Sharpei Club Hong Kong based its breed standard on the traditional bone-mouth standard.

“Sleeping Beauty” by Karen McClelland
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At the bottom, a chinese roof tile