👉 Aperture dentin, also known as an apertured tooth, is a type of dental tissue that develops from the outer surface of the enamel (the outer layer of the teeth) and is usually found at the apex of teeth. Aperture dentin is typically less dense than the surrounding enamel and is considered to be a part of the natural process by which teeth are formed. It can also be referred to as an apical tooth or a dental ridge.