I have a mom whose baby is now 15 weeks and still creases her nipple after
every feeding. On suck assesment this baby also bunches her tongue toward the
back but also tried to move lateral. This poor mom went through months of
mastitis, yeast infections and sore nipples, we have resolved the first two
problems but the sore nipples continue. She will be getting an evaluation from
an oral/speech path. When I get the report I will share it with you and see if
there is anything you can offer or help her with.  This baby never had a
problem with a bottle ( used a Haberman and had mom use tongue training any
time she used the bottle.
Ann Perry RN IBCLC