1) Brush my teeth & lips immediately when I wake up every morning (including the tongue & the inner side of cheeks) in order to remove the white stuff that is still liquid. The white stuff is the origin of the crust when it dries.
2) Remove the white stuff of the morning with water at 1 PM o'clock (after the lunch)
3) The same thing as 1) the evening before going to bed
4) Apply some vaseline before going to bed on lips and inner side of gums in order to avoid the maximum amount of white stuff to dry.
5) Use a hydratant lotion like EVIAN AFFINITY after having applied chapstick several times during the day
The crust will be thinner with this procedure but (for me) it's still painfull when the upper crust goes away (every week) because the area underneath is more deeply irritated. Although it was worse 10 years ago. (I bite my top lip and it never recovers. Moreover the e.c. moves to the bottom lip 5 years ago - maybe due to an inappropriate cream)