Methods: 104 sets of dental casts were collected from adults (>16 years) who had not had orthodontic therapy and who had all upper and lower anterior teeth present. The casts were scanned digitally alongside a scale and stored as JPEG files. The inter-canine measurements were carried out using Adobe Photoshop Version 7TM from cusp tip to cusp tip. In cases where the canine was worn the centre of the wear facet was taken as the measurement point.
Results: The mean maxillary inter-canine distance in males (n=64) was 33.47mm +/-2.43 and the mean mandibular measurement was 25.5mm +/-2.27. In females (n=40) the mean maxillary inter-canine distance was 32.25mm +/-2.56 and the mean mandibular measurement was 25.1mm +/-2.04. One of the females had the largest mandibular inter-canine distance at 32.2mm which was wider than her maxillary measurement (31.4mm). Statistical analysis was carried out using a standard two-sample t-test to compare maxillary and mandibular measurements between males and females; these were found to be significant for maxillary (p=0.016) but not mandibular (p=0.236) measurements.
Conclusion: The inter-canine distances for males and females obtained here fall within the ranges of values reported in other studies. Although a statistically significant difference was found between the genders for maxillary inter-canine distances, there was a large overlap in the data sets suggesting that attempts at gender identification from maxillary inter-canine measurement would not be reliable.