Hi @MotherDuck367 ,
That sounds really hard, especially when your kids are still so young. Dealing with different parenting styles and house rules when parents have separated can be an incredibly challenging part of life as a single parent. To a certain extent, some of this stuff may be out of your control - as long as the kids are safe, fed, and happy, unfortunately standards of cleanliness may be something that you have to let slide, as long as it's not unsafe or unhygienic. That being said, I would think it's a basic requirement that things like teeth cleaning and baths happen. I think it's totally valid to express concerns about teeth not being cleaned, and it's unfortunate that your ex seems to have got pretty defensive about that.
I'm wondering if you and your ex partner have a parenting agreement at all? Some people find it helpful to have a plan that lays out basic expectations, the Raising Children's Network have a good resource about co-parenting plans and different strategies here that might be helpful too.
I'll tag a few other single parents/ people in blended families here to get their input too @Stepmumma4 , @AudreyRose-94 - I really feel for you, I was a sole parent for several years (though in my case I had sole custody), it is an incredibly tough gig, and it sounds like you're doing a wonderful job. I know how relentless life as a single parent can be, are you able to use the time when you don't have your kids to do something that recharges your batteries a bit?
If you're ever looking for someone extra to talk to, we do also have a free one to one parents support service, you can access that here.
Thanks for posting here, and let us know how you're getting on 
