facetile files

I have accidentally deleted a few facetile files and so, when I select "People" from the major heading options, a few of the named persons do not have a picture in the corresponding circular image pictures. However, the appropriate media pictures are called up if I click on the circle - even though there is no image in the circle.

Is there anyway I can get the facetiles written again? By getting the software to search again for faces perhaps?