Interpretation of Martin Parr's photgraph

This photograph of Martin Parr, taken in 1999, shows a Caucasian individual wearing red lipstick smiling broadly. Upon careful observation, you can see traces of lipstick on the otherwise gleaming white teeth. It also appears that there may be some plaque along the gumline.
What I also noticed is that it is not apparent whether this grin is a genuine smile, or a forced one, as the eyes are not seen. This person may have been caught in a laugh, or this photograph may have been taken after some yelled "Smile!"  Since the eyes are not in this picture, it is not readily apparent of the circumstances under which the photograph was taken.
This photograph also shows some contrasts as to what is meant by a perfect smile. The teeth appear gleaming white. The lipstick seems to be perfect. But the traces of lipstick on one tooth suggests that even what seems to be perfect may have some flaws. The slight appearance of plaque along the gumline may suggest that though we think our flaws are covered, some may still be seen.