What is remineralization vs regrowth or teeth, what is the exact definition of remineralization?

Here is the definition of REMINERALIZATION OF TEETH by oralhealth website: remineralization is the natural repair process for non-cavitated lesions. It relies on calcium and phosphate ions, assisted by fluoride, to rebuild a new surface on the existing crystal remnants in the subsurface. The remineralized crystals are less acid soluble than the original ones. Look for more information by yourself.

Remineralization is the replacement of calcium and phosphorous ions that have been etched from the enamel by acids produced by bacteria. There are products available, combined with lifestyle changes, that can help replace these chemicals in very early areas of decalcification. Your Dentist can help. Know that teeth do not regrow. Again, ask your Dentist.