Angle’s morphological clasification is only one among the sagittal maxillo-mandibular relation indicators in the current orthodontic diagnostics. A study was conducted therefore to ascertain the differences between the occulusal and maxillo-mandibular relations, and to assess their significance by means of roentgencephalometry. The sample consisted of 200 roentgenograms of the subjects divided into classes , II or III according to clinical criteria. The skeletal maxillo-mandibular relations were assessed on the roentgenographic displays using 7 separate variables. The findings indicating the existence of differences between the occulusal and skeletal classifications as well as in the methodology applied, were statistically processed and tested. From the significance of the established difference percentages, the occlusal relation of the first permanent molars could be described as an unreliable and insufficent indicator of the jaw relations, pointing to the need of a simultaneous roentgencephalometric methodology in assessments of this type.