This should not have been permitted to happen, except in the most
extensive treatment plans that are expected to take a long time to
complete.  I'm sure you've fallen through the cracks.
    I don't know what dental school you're dealing with.  If the students
are gone for the summer, most or all of the faculty is too.  However,
the school can't be totally locked down.  There may be a clinic chief or
dean, who should be able to set this right.
    There is a good chance that everything will be alright anyway, but
temporaries crack, wear, fall off, and I can't assure you that the tooth
will be fine.  IMO the school should make an effort to have you seen by
someone.

Steve