Making suture bone effect zbrush

Hi guys , i have 2 symmetrical parietal bone models that i ve mirrored in zbrush.
as you can see in the picture below the middle part is perfectly lined each other. but im trying to make a jagged intersection effects on both of them for the “internal surface”, similar to the second picture.
i ve come up with some ideas like boolean or grouping them but i couldnt really figure out the best way to do this intersecting effect to look natural. any ideas?? :sweat_smile: