In Animal Dentistry and Diseases of the Mouth, by Louis A. Merillat, published in 1906, “blunting of the first molars” in horses is described in detail.  The text provides instruction for accomplishing this task as a “method by which the sharp points on the molars may be blunted with but little labor.”

      Any points on teeth in horses’ mouths can be uncomfortable when contacted by the tongue, lips or cheeks, so the first benefit of this procedure is obvious: remove sharp corners.  It is also helpful to eliminate upper hooks or lower ramps, in cases of malalignment of upper and lower cheek teeth arcades, where the upper sixes are not in direct opposition with the lowers but are either too far forward or too far posterior, respectively.

     While it may be true that simply eliminating the sharp points or corners from the fronts of the first cheek teeth is sufficient benefit to justify bit seats, other equally important advantages include preventing bit pressure on the tongue, and easing the path of long-stemmed grass and hay into the molar tables for mastication.

      Many dental practitioners provide bit seats only for performance horses because the bit is likely to cause pinching of the cheeks, lips or tongue against the teeth.  As Dr. W.L. Scrutchfield states in Equine Dentistry, “The procedure is done in an attempt to make the performance horse as comfortable as possible as the bit pulls or pushes soft tissue against the second premolars.”