Introduction. More recent research points out to the existence of a new concept of the technique for locating the neutral zone. The objective of the study was to determine the effect of changing vertical dimension of occlusion, as well as that of the alveolar ridge type, on the neutral zone dimensions. Material and methods. The neutral zone was investigated in two groups of patients, with prominent (the control group) and flat alveolar ridges and it was determined for each patient at 3 heights (the correct, the increased and the decreased vertical dimension of occlusion). It was studied both vertically and horizontally. The width of the neutral zone was measured in different regions. Results. The width of the neutral zone was minimal at the level of the occlusal plane, and it increased gradually as the occlusal plane went down and up, towards the anterior region. Conclusion. No statistically significant difference was found in the width of the neutral zone, between the group of patients with prominent alveolar ridges (the control group), and that with the flat ones. There was, also, no difference at all, at any level of the vertical dimension of occlusion, that could possibly bear statistical significance.