The sculpture above the painting was done by Jean-Jacques Caffieri in about 1755.  The composition is completed by corner sculptures of the Doctors of the Church (example: St. Jerome) by Augustin Pajou (1730-1809).

Caffieri's Trinity (see detail) adapts the Trinity image type prevailing in his time (Son at Father's right holding a cross, Spirit as dove above and between the two -- example) by giving the Son a crown that he holds ready for Mary and by moving the dove down toward the painting in order to make it seem to be the source of the light that flows into the painting and bathes the Virgin.

Detail of the Virgin
Detail of the Apostles

More of the Assumption