How long is the baby's oral period?

Babies have different oral teeth. It is oral cavity to search by putting an object in the mouth. What is this with a well-developed mouth because other organs are still underdeveloped? It feels like, but it is considered that it is often brought up to about two years old if it is late. Even after the age of three, it's natural to bite in your mouth from time to time, so you don't have to worry about it, so there are a lot of toys with various safe products. The important tip here is that you like long parts of toys and tags, so please remove products that get stuck or stuck in your mouth as much as possible. I raise children in a slow way. The best advantage is that I feel that the baby's expression is diverse and rich. As there is no correct answer to parenting, I explained how to raise it in my own way. Have a nice day