Let's just say that the crown of a tooth is wider than the root, forming a shape with a wide top and a narrow bottom. If you are missing a tooth, then the teeth on both sides of your missing tooth are trapezoidal in shape, that is, the gap at the bottom is wider than the top, and the teeth on both sides form the hypotenuse on both sides of the trapezoid. Mathematically speaking, a straight line perpendicular to the bottom is made from both ends of the trapezoid, thus forming two triangles, left and right, with a rectangle in the middle. Then the triangles on both sides are called inverted concave areas (for better understanding, it is vertical, strictly speaking, it is not necessarily vertical. If multiple teeth are restored, there may be a certain inclination angle in the direction of finding several teeth in place.

I don't know if I made myself clear.

You got it?