You will hear this a lot on this site.

You can't care more than their own parents.

My sons were terrible about brushing and flossing when they were teens. I cajoled, I threatened, I rewarded, nothing seemed to work. Their dentist was brilliant. She complimented them and told them what beautiful smiles they had. She teased them about how all the girls must love their smiles. Told them they could be models with such great smiles. It made them want to keep their lovely smiles and they started brushing and flossing.

Exactly what notsobad said - you cannot care more than the parents.  I experience the same...DH is a wonderful husband.  As a father, he falls short.  SS15 hasn't been to the dentist in well over a year.  DH just cancelled the appointment I reminded him to make because he had to work.  I will not say anything and I bet he'll never go until there's a problem.

Some people just should not have children...

OMG, are you serious?? That is so gross. They just don't brush at all or use body wash?? Good grief. I'm sorry, but that really is terrible parenting. During summer and wknds, we have to nag skids to brush. During school, they automatically do it now (because we nagged them so much, they know they have to) when they wake up. I tell SS that his girlfriend (it's 6th grade so it's not like they're making out) will not want to be near him if he has stinky breath, and I think that actually helped motivate him a bit. That being said, my SO slacks on dentist appointments as well, and during summer almost never made them brush, it was always me telling them, or telling SO he needed to make them brush.

It's ridiculous that you are the only one that cares, and that no one is teaching/enforcing hygiene. So gross.

You cannot do more than the parents.  SD14, almost 15, has always hated brushing her teeth (it's a bother, it's gross, I don't like the brush, I don't like the flavor, I'm too tired, etc., etc., etc.).  DH did not make her do it.

So I stopped asking when she was around 10.  Now she is likely having major dental issues (but I don't know b/c she herself didn't say anything)....the last I knew of, over a year ago she had multiple soft spots on all her teeth.  Her breath was like death.  She couldn't eat crunchy food b/c it hurt.  Her toothbrush/paste were in her dresser in her bedroom.

And I could care less.

You'll find that a lot of us are on this site because we are married to people who are lazy/week/ineffectual parents. These are people who've already failed at at least one significant relationship, despite the "my ex is crazy!" excuses we are fed.

I happen to be married to a man who treats me like a queen but is a terrible-awful-no good-very bad parent. I martyred myself for a looong time, including raising his hardbroke youngest daughter for five years. MY time, MY emotion, MY resources. All wasted, like pearls before swine in this unnatural blended family dynamic. It didn't change the inevitable outcome at all.

It's common to see posts where SMs provide the bulk of care for skids. We've had posters who fell in love with a man and found themselves living a life of drudgery as an unpaid nanny, cook, maid and bed warmer. Many of us have stepped up because we see skids who in the aftermath of divorce are not being parented well - or at all. It's sad and.frustrating, but far above our paygrade.

You can either disengage, nag the parents, or go back to being the nanny. But none of this is your.responsibility.