My LO has 12 teeth but is back to biting everything these days. I think he might be getting a molar. Did your babies continue to teethe when they got molars? I thought after their first few teeth, they got used to the pain?

A full set consists of 20 milk teeth, so it is possible that he is feeling uncomfortable from the emergence of the molars. I don't think it is possible to get used to any kind of pain. Childbirth doesn't get any less painful with subsequent deliveries. Moreover, the molars cause more discomfort and pain than incisors. http://sg.theasianparent.com/the-go-to-guide-for-your-babys-teething/

LOs bite when they are frustrated or they are teething. Maybe you should keep more toys around since it is potentially dangerous for other kids around.

Massaging sore gums, offering something cold, or acetaminophen on an occasional rough night, can help soothe your baby's teething pain.

thanks