Compare Textbox values

I have to textboxes that I want to compare so I can have a message box alert the user to incorrectly entered values.

I can't seem to get the compare to work.

textbox1 > textbox2

This is what I have:

Dim NTGvar, NTPvar As Variant

NTGvar = textbox1
NTPvar = textbox2

If NTGvar > NTPvar Then
MsgBox "Number of Gear teeth can not be less than teeth in Pinion", vbInformation + vbOKOnly, "Number of Teeth Error"

Thanks for the assist
David