The mean width of the philtrum was found to be 7 mm in infants by Franz and Sokol [1971] and 9.7 mm in adults by Ward and Jamison [1991]. Measuring width of the philtrum is even more inaccurate than measuring length (vide supra). A broad philtrum may be associated with reduced ridge prominence or a shallow groove, a Smooth philtrum, which should be assessed and coded separately. It may be found with a broad nasal septum.