Discolored teeth help

[chaz2000]

I'm relatively new to gimp.
I took some pics of a lady friend. Her husband says that she is sensitive about the discoloration of her teeth. It looks like she has caps on the bottom of her two top front teeth.

I tried:
making a new layer
using the lasso selector, select the darker area of the two teeth
in the colors menu, selected and decreased the Hue-saturation. (didn't work)

Appreciate your help.

[PixLab]

(10-20-2021, 07:41 PM)chaz2000 Wrote: I'm relatively new to gimp.
I took some pics of a lady friend. Her husband says that she is sensitive about the discoloration of her teeth. It looks like she has caps on the bottom of her two top front teeth.

I tried:
making a new layer
using the lasso selector, select the darker area of the two teeth
in the colors menu, selected and decreased the Hue-saturation. (didn't work)

Appreciate your help.

A very quicky to show a process, but you will do a better selection (feathered) and fit properly  
(In my example I forgot to feather the selection, did I said it was a quicky?)

Duplicate ➤ work on the top layer only (we use it only for the teeth)
Select properly the teeth (not like me )
Use Colors ➤ Curves...

   

Once you equalized the whiteness use your selection to make a mask which will remove the degraded pixels generated by the process,

   

To smooth the mask out blur the mask slightly (gaussian blur)
To make the mask fit as closed as possible Filters ➤ Distorts ➤ Value propagate... chose Mode "black" then Ctrl+F as necessary (it's just by 1 pixel),
blur the mask slightly at the end if necessary ➤ only if smoothing is needed again

the .xcf file

  Untitled.xcf (Size: 521.5 KB / Downloads: 151)

result