Broken teeth- cap 'em or pull 'em. That's about it. Receding gum line- you can try to do stuff to slow/stop the recession. Receding gums usually is indicative of a deeper problem- gingivites (how DO you spell that?), over brushing, teeth shifting from dental work like braces.... For gingivites, your gums become inflamed, the inflammation causes pockets where more bacteria hide, your gums swell and pull away from your teeth more and lose that adherence and then they start to recede once they don't have that good "hold" on your teeth. The first thing you need to do is fix the reason for the recession. Do your gums look red and swollen? If so, that can mean active pockets of bacteria. Brush gently but very thoroghly on the affected areas if it's over brushing, and dental work... eh, you live with it. Once that's cleared up, you get mega doses of antibiotics and they use some tissue usually from other parts of your mouth to replace the missing gums in a graft.
I have recession issues in the bottom front- I have for years and years and years. Pregnancy made it a million times worse and I'm scared of losing my teeth now too, but it requires gum grafting to fix the receeding gums and that requires you to not be pregnant and ideally not breastfeeding which hasn't happened at all for about 4 years now!
What I'm doing: Pregnancy makes my gums swell and bleed. It's a common problem. My dentist says I just need to brush and floss more often but that doesn't fix it, it just bleeds more. So I'm doing a regular mint toothpaste with a drop of tea tree oil on it OR a drop of oil of oregano - just one drop, and this is just once a day though I try to brush twice at least! Neither of these are approved for use in pregnancy, but I've talked to a bunch of people- 2 naturopaths, two coworkers who know everything, and a my midwife to name a few- and they all said it should be fine in such tiny amounts, especially since I'm not swallowing it. Then I either add just a pinch of himalyan sea salt to my brush or do a mouth was with sea salt after. It really helps with the swelling and discomfort, and that should slow the recession until I get a chance to fix it. And the $4000 to fix it. Hmm.
I've also heard a lot recently about oil pulling- swishing oil in your mouth for a LONG time to pull out toxins- but a few people I asked about it said they'd caution against it in pregnancy except in extreme cases.