Can tooth abscess and tooth infections cause enlarged lymph nodes in neck?

Yes: Depending on which tooth is infected, however if it persists after 6 weeks and tooth infection is resolved, then need to have a medical evaluation for more serious causes!

Definitely, yes: A tooth abscess is a pocket of pus that's caused by a bacterial infection. Tooth infections can spread to other areas of the mouth and cause extensive tooth loss, or compromise the immune system – and although rare, may become life threatening. The swollen glands of the neck and enlarged lymph nodes are common symptoms of the tooth abscess. See a dentist ASAP.