Conclusion
Regrowing teeth as an adult as of now is not possible. But research is being done to make it artificially possible. You should talk with your dentist about any dental problem you are having. They’ll be able to recommend ways to keep your teeth healthy and prevent further tooth decay.
References;
[1] https://www.medicalnewstoday.com/articles/cavity-filling
[2] https://www.mayoclinic.org/diseases-conditions/cavities/symptoms-causes/syc-20352892
[3] https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
[4] https://www.healthline.com/health/bleeding-gums
[5] https://www.nhs.uk/conditions/tooth-decay/