The association between the presence of palatally displaced maxillary canines (PDC) and other anomalies is well known, particularly with regard to the size and form of the lateral incisor. The present study investigated the connection between the maxillary canine anomaly and the existence of a reduction in the size of the other teeth in the maxilla in 58 consecutively treated patients (37 females, 21 males) aged 11-15 years, and compared these with a control group of 40 consecutively treated subjects (20 males, 20 females) with normally erupted maxillary canines. The findings indicate that the teeth of PDC males are reduced in size and similar to those of PDC females, in sharp contrast to the general population, where males have larger teeth. This is the result of a dimensional reduction in the teeth of PDC males, which was statistically significant for all teeth (P < 0.01) in the bucco-lingual (B-L) dimension, and for the first premolars and first molars in the mesio-distal (M-D) dimension. The sole teeth affected for both sexes were the lateral incisors in their B-L dimension. Bilaterally and unilaterally affected subjects presented differing M-D and B-L tooth dimensions.