Protecting your own teeth.
First-Line: Protect your enamel from irreversible damages.
You have only one set of permanent teeth, and only one set of 1mm thick enamel (outer skin or shell of teeth), just like the egg-shell protects the egg, or the impregnable skin of an orange or apple protects the inner fruit, so who wouldn't want to protect them forever? Aside from potential decay, tartar, stains, gum disease and gum recessions, whereby regular checkup and cleaning is important, but also over time everyone's teeth are also highly prone to structural deterioration, wear-and-tear, often due to abrasion (over-heavy daily brushing) which might also cause irreversible gum recessions, attrition (night-grinding, bruxism), and erosion (stomach acids, acidic drinks or citric foods). Avoid over-brushing abrasion by using electric toothbrush; avoid night-grinding attrition by wearing night guard; and avoid erosion by taking a final sip of water after every meal. Enamel (outer teeth skin) is the most important layer to protect the rest of your teeth from sensitivities, and bacteria from entering into the dentine and infect the inner nerve structures to result in root canals, crowns, etc. Severely worn enamel is often the root cause of numerous problems, this can and must be reinstated to its original form either by optionally adding composite bonding (white protective composite resin coating) or by adding fissure sealants to top-up your biting surfaces. Enamel does not grow back and is the first and most important tooth layer that must be preserved indefinitely, in the first place. "Prevention is better than the cure". Good Knowledge and Personal Awareness is paramount.