When i'm over RadMaskedNumericInput control the scroll screen not work. In short, RadMaskedNumericInput's MouseWheel Event no trigger although the control is set <telerik:RadMaskedNumericInput SpinMode="None"/>
The RadMaskedInputControls handle internally the MouseWheel event and that is why this event does not fire when you subscribe for it. A possible way to trigger the MouseWheel event of the RadMaskedNumericInput is to inherit its class and override the OnMouseWheel() method.
public class CustomMaskedNumericInput : RadMaskedNumericInput
I attached a sample project that demonstrates the suggested approach. When you run the example you will see that in XAML there are several Buttons and the CustomMaskedNumericInput wrapped in a ScrollViewer. This is done to demonstrate that the MouseWheel event will trigger the scrolling of the ScrollViewer even when the CustomMaskedNumericInput is focused.
However, we are not entirely sure what you are trying to achieve. If this is not exactly your case could you please elaborate a bit more on it ?