1
general::
Phrase(s): bring something to a head
to cause something to come to the point when a decision has to be made or action taken. • The latest disagreement between management and the union has brought matters to a head. There will be an all-out strike now. • It’s a relief that things have been brought to a head. The disputes have been going on for months.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Cause to reach a turning point or crisis. For example, Management's newest policy has brought matters to a head. The related phrase come to a head means "to reach a crisis," as in With the last break-in, the question of security came to a head. These phrases allude to the medical sense of head, the tip of an abscess that is about to burst. [Mid-1500s]
American Heritage Idioms