Teeth whitening works by using either hydrogen peroxide or carbamide peroxide to break down and remove stains on the enamel. These bleaching agents penetrate the tooth's surface, reacting with the discolored molecules and breaking them apart. This process effectively lightens the color of the teeth, resulting in a brighter and whiter smile.

Yes, teeth whitening is safe when performed by a qualified dental professional or using over-the-counter products as directed. However, overusing or misusing whitening products can lead to tooth sensitivity or gum irritation. So, it's essential to follow the recommended guidelines, especially for individuals with existing dental issues.

The duration of teeth whitening results varies depending on factors such as lifestyle, diet, and oral hygiene. Typically, professional treatments can last anywhere from several months to a few years. At-home whitening products may require more frequent applications. Avoiding staining foods and beverages and maintaining good oral hygiene practices can help prolong the effects of teeth whitening.

While many individuals can benefit from teeth whitening, it's essential to consult with a dentist to determine if it's a suitable option. Pregnant or breastfeeding women and individuals with certain dental conditions or allergies may need to avoid whitening treatments. Additionally, teeth whitening may not be as effective for individuals with intrinsic stains (inside the tooth) as opposed to extrinsic stains (on the tooth's surface).