I knew the frustration learning the dentition of canine and wondering why they always looks weird or I couldn't get it right. Here are the landmarks and constants i've learned along the way.
Photoshop is not working and I don't like the way the paint text looks, so deal with my shitty handwriting.
Green: Eyes should be affected by divider line.
Red: RARELY does the corner of the mouth exceed the corner of the eye. ^{I say rarely because you will see it in a few newer breeds, however, this rule is a good guideline until you learn what beyond the eye is a normal, natural length.}
Orange: PHILTRUM DOES NOT CURVE.
Purple: Imagine the jaw closing. Lower canine should, and must, meet up with the gum-gap infront of the top canine. This is called a scissor bite.
And the yellow golden rule, If the snout goes up, the forehead must come down.

Hope this helped a few of you. Remember this is what works best for me , it may not work for everyone.

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