The root canal width (yellow dotted line) was calculated as the percentage of the width of the whole root (blue line) of the maxillary canine teeth halfway between the cementoenamel junction (white dashed line) and apex of the tooth (white arrow). For each specimen, mean root canal width was measured from both maxillary canines. If a maxillary canine tooth was missing, demonstrated signs of endodontic disease, or was fractured below the level of the cementoenamel junction, the other canine tooth was solely measured. No skulls had bilateral compromise of maxillary canine teeth that would have precluded this assessment. In this case, the whole root width was measured as 680 pixels and the root canal width was measured as 236 pixels, resulting in a root canal width of 34.7%.