The dental structure mostly used by lemuriform primates to comb fur during grooming is the toothcomb.
A lemuriform toothcomb is a row of forward-tilting lower teeth at the front of the mouth. In most lemuriforms, it includes four incisors and two canine teeth, although some indriids have a four-tooth version. The closely spaced teeth work like the teeth of a comb during oral grooming.
As a lemur runs the structure through its fur, hairs and debris can collect between the teeth. A specialized under-tongue, called the sublingua, helps clean the toothcomb. Grooming is considered its primary and original function, although some lemurs also use the structure to gather fruit pulp, scrape plant gums, or gouge bark.
The toothcomb is not the same as a sagittal crest, which is a ridge of skull bone associated with jaw muscles. A dental pad is a soft structure found in some mammals, while a diastema is simply a gap between teeth. The aye-aye is a notable exception: its toothcomb has been replaced by continually growing incisors.