Recent studies have supported the hypothesis that there is a tendency for evolution in the occlusal relationship of urban populations. In our population , particular interrest is born to incisor guidance and its role in stomatognathic system. Incisal situation and relatioships can be studed with anthropometric and cephalometric determinants This study compares the incisal relationship of two populations of conscripts to the Austrian army, born in 1870 and 1970 respectively. Twenty-four anthropometric and cephalometric points were analysed for 30 subjects from each population. A statistically significant difference between the 1870 / 1970 populations was found for the following criteria (p Keywords: anterior guidance, secular evolution, incisors, orthodontics