M having 3yrs 9month old boy kid. From his 1st year age he was biting lips means he put his upper teeth out tightly he bite oveenight. We tried lot to stop but he doesnt. Now he stopped doing like that. But his teeth gum come down and while he smiles gums will look. I am afraid of this. Earlier when he smiles gums were not seeing. What to do to push gums back.. Please tell... When his milk teeth fall down new teeth come then also whenn hevsmiles gums will lools or what.. Please reply