Vertikale Lage der Mandibula zu den Halswirbeln

The vertical position of the mandible in relation to the cervical spine during growth was analysed by means of 1538 records of lateral headfilms of 232 individuals between the ages of 6 to 30 years. These longitudinal data stem from two different projects at the University of Groningen / the Netherlands. Distances were mesured and evaluated on the roentgenograms after standardizing the head position. After grading the measured streches due to sexes, seven age groups were created and streches were assigned. The distances were analysed statistically. Mean values, standard deviation and number of valid cases were calculated as well as correlations coefficients. Diagrams were constructed to depict the results graphically. As a result of this investigation the following conclusions were formulated: 1.The amount of vertical growth relative to Basion was nearly tidentical for Menton and Gonion-Intersection. Menton underwent a slightly larger change, 14 mm growth in females and 17 mm in males, compared to Gonion-Intersection with 12 respectively 16 mm. 2.The vertical position of the mandible relative to the cervical spine proved very satble during growth. Gonion-Intersection and Menton experienced a slight downward shift relative to the cervical spine, about 2,5 mm for Gonion-Intersection and 2 mm for Menton). 3.The vertical position of the PNS, the posterior nasal spine, clearly was diffenrent from the other data. Vertical developement of the PNS did not correlate with that of the mandible nor with that of the cervical spine. Rather, a fairly constant relationship between PNS and Basion has been observed. 4.A relationship between the vertical growth of mandible and the cervical spine was evident. This relationship fits the counterpart principle as described by Enlow (1982): The mandibular angle (reference point Gonion-Intersection) showed a vertical development equal to Dens axis. The chin (reference point Menton) and Cervical vertebra III displayed an analog pattern. Moreover a very similar vertical development of PNS and Basion existed. 5.The sexual differences were the same during development of the mandible and the cervical spine. The growth period in boys lasted longer than growth period in girls. Furthermore, the growth spurt occured later and was stronger and the final height was larger in boys.