Dental abnormalities develop commonly in horses as a result of modern feeds and feeding practices. These abnormalities, including sharp enamel points, are commonly associated with ulceration and mastication problems and results in pain, discomfort as well as interference with chewing function. A range of treatment procedures, involving removal and modification of the dental structures, have been developed. The effects of these on alleviating pain and discomfort and improving jaw function have not been previously evaluated. The jaw motions of 15 thoroughbred horses (5 geldings, 7 fillies and one colt, two years of age, in medium work and fed typical rations of oats, chaff and hay, and typical sharp enamel points and ulceration) were recorded using an optical motion capture camera system. The recordings occurred during 20 minute periods of chewing oats and hay. They were done before, immediately after, and one week after dental treatment. The data obtained were transformed into a 3D Cartesian co-ordinate system to calculate jaw displacement relative to the head. The displacements during the phases of mastication were compared using two-tailed paired samples t-tests. Horses chewing oats increased their opening stroke (dropping the jaw and placing food) (from 9 mm to 16 mm, S.E. = 5, P<0.001) before and immediately after treatment, and chewing hay it decreased from 19 mm to 11 mm (S.E. = 3, P<0.026). The closing stroke (bringing the teeth together) decreased one week after treatment from 26 mm to 22 mm (S.E. = 3, P<0.026). Total average speed (mm/s) of chewing increased from 39 mm/s (S.E> = 2) to 63 mm/s (S.E. = 9) for oats immediately after treatment. These findings are consistent with alleviation of pain and discomfort through the application of the dental procedures.