The study group consisted of 73 North American patients (29 males and 44 females), aged between 0-5 months and 20 years, 26 with right, 33 with left, and 14 with bicoronal synostosis. Basic proportion indices were established in 5 craniofacial regions (cranial, facial, orbital, nasal, oral) calculated from 2 projective measurements [cranial: eu-eu, g-op; facial: n-gn, zy-zy; orbital: en-en, ex-ex; nasal: al-al, n-sn; oral: sn-sto, ch-ch (eu, eurion; g, glabella; op, opisthocranion; n, nasion; gn, gnathion; zy, zygion; en, endocanthion; ex, exocanthion; al, alare; sn, subnasale; sto, stomion; ch, chelion)] taken from the patients by the first author before surgery. These data were then compared with the anthropometric norms established for North American whites (Farkas LG. Anthropometry of the Head and Face. 2nd ed. Raven Press; 1994). In males, the total percentage of normal, subnormal, and supernormal proportion indices was smaller than in females in all 3 groups of patients. Generally, the difference in percentage between normal proportions was the smallest (13.1%) and the supernormal one the greatest (68%). In males, the oral measurements showed the highest frequency of normal proportions (100%) in all 3 patient groups, and the cephalic index the lowest (60%-66.7%). Among the abnormal proportions, the supernormal ones were found more often, especially in the cranial region of females with bilateral coronal synostosis (66.7%). Subnormal proportion indices were rare: none were seen in the facial region of males. A subnormal cephalic index (eu-eu/g-op) was not present in either sex in right and bicoronal synostosis and was observed in only 2 males with left coronal synostosis (13.3%). The study showed that the influence of synostosis gradually decreased from the top to the bottom of the face, with the oral region showing no abnormalities.