The chin really should be handfed with critical care and maybe some life line. This little chin has to be eating several times a day to ensure that the gut motility is maintained. Sometimes when a chin hasn't been eating gut motility drugs should be given with simethicone to keep things moving and keep gas from building up in the intestinal tract.
Chins just have to keep eating all the time. After this chin's mouth stops hurting she should go back to eating more on her own. Chins with tooth problems can be so delicate and require so much care.