The length of each tooth is different, but the normally developed teeth are between 22mm and 3 1mm, among which fangs are the most common, that is, tiger teeth. Molar teeth (that is, back teeth and big teeth) should be short, but thick. (Don't say the specific length of each tooth? I didn't take my book to the internet cafe ...)

Talking about "What is the best depth of incisor occlusion?" Before this question, let me talk to you about dental coverage and dental coverage.

Tooth surface coverage refers to the situation that maxillary anterior teeth cover mandibular anterior teeth at a horizontal distance.

Tooth overlap refers to the situation that maxillary anterior teeth overlap mandibular anterior teeth in vertical distance.

If the mandibular teeth cover the maxillary teeth in turn, we call it reverse jaw. That is what people often say, "the sky is full."

In this way, the normal occlusion depth of teeth is 1/3 where the upper teeth cover the lower teeth. At this time, the biting depth is the best.

Therefore, maxillary teeth are generally more prominent than mandibular teeth (I really don't know how much). When the masseter muscle relaxes, the gap between them is about 0.5mm, which is called "resting jaw space" in medicine.

In addition, the mandibular teeth will not contact the gums of the maxillary teeth when occluding. If you touch your gums, it directly means that you are deeply covered.

As for the last question, I really don't know how to answer you. "Why should the teeth of the upper jaw be more forward than the lower jaw?"

It's like asking God, "Why do you want to divide men and women?" Same. It may be that human beings are born, it may be God's care for human beings, it may be the result of natural selection and evolution, or it may be that maxillary teeth and mandibular teeth used to be good friends ... one day, they quarreled ... to prove who is better. ..................