Do homemade mouthwashes with salt and baking soda work?

They work to clean a bit and reduce bacteria, but honestly they're not as effective as a commercial fluoride rinse, especially if you want to prevent cavities. I always say it's fine to use them once in a while, but don't confuse them with actual dental care.

They work pretty well for cleaning and disinfecting, especially if you have inflammation or mouth ulcers. I use them when I'm having trouble and honestly it does help, though they don't replace brushing or going to the dentist of course.

I've used those homemade rinses when I had inflamed gums and honestly they help, especially baking soda which is kind of miraculous for cleaning. But yeah, like you're saying, they're not gonna replace a good fluoride rinse if what you want is to prevent cavities long-term. I use them now more when I have some specific irritation or canker sores, combined with everything else obviously, but as a daily treatment I don't really trust them as much.

As a pharmacist I can tell you they do work, but you gotta be realistic about what they do and what they don't. Salt has antiseptic properties and baking soda helps neutralize acidity, so for mechanical cleaning and reducing inflammation a bit they're good. If you have aphthous ulcers or irritated gums, these homemade rinses can really give you some relief, seriously. The problem is they don't have fluoride, which is what you need to strengthen enamel and actually prevent cavities.

What happens to me is I see people who stop using decent commercial rinses thinking that salt and baking soda is enough, and that's just not true. I'm not saying don't use them, but they shouldn't be your only rinse. If you make them right (a small spoonful of each thing in warm water), they'll work fine as a complement, for when you have discomfort or inflammation. Now, for a daily cavity prevention routine, better to use a fluoride rinse. And well, none of this replaces brushing with fluoride toothpaste three times a day.

So my recommendation is use them when you need them for relief, but don't make them your main rinse. Personally I think they're practical because I know exactly what's in them, but I'll admit they're not as complete as what they sell at the pharmacy. And when you're actually worried about your oral health, talk to your dentist, that's what they're there for.