Tetraodontiformes includes approximately 350 living species of pufferfishes and allies. Oral teeth of tetraodontiforms vary widely in morphology, from several pointed individual teeth seen in boxfishes (Ostraciidae) to the single fused dental beak of ocean sunfishes (Molidae). Comparative dental morphology of tetraodontiforms has yet to be fully characterized using available technology such as Computerized Tomography. We present an in-depth morphological analysis of oral dentition within Balistoidea, a subgroup within Tetraodontiformes, to understand differences between its two living families, Balistidae (Triggerfishes) and Monacanthidae (Filefishes). We describe the morphology and replacement modes of the oral dentition of exemplar species from the two families using osteological materials, histological sections, and CT images, and place these observations in the context of dental structure in other lineages of tetraodontiforms. Balistoids are unique within tetraodontiforms, and other teleosts in general, in that they have a mammalian-like tooth formula in which tooth sizes but not numbers increase during life. Additionally, their teeth occlude like a chisel pounding against an anvil in a way that is similar to the incisor teeth of rabbits. This arrangement combined with an elongate central cusp maximize crushing effectiveness in a pattern different from other tetraodontiforms.