Difference Between PAP and PAP+ While some modern teeth whitening products use PAP, others, like HiSmile use a more advanced version of the same, known as PAP+. So, what is the difference between PAP and PAP+? The + symbol in the PAP+ formula refers to the added ingredient nano-hydroxyapatite (Nano-HAp). Hydroxyapatite (HAp) is a naturally occurring calcium apatite found in saliva, teeth, and bones. This ingredient remineralizes teeth by replacing the minerals and strengthening a weak enamel. The nano-synthetic version of the HAp used by some brands like HiSmile works more efficiently as the particles are smaller in size, therefore, able to penetrate deeper and fill in more areas of the damaged enamel at a much better and faster rate than fluoride. Moreover, the PAP+ formula from HiSmile includes potassium citrate. This ingredient helps with any sensitivity issues you may have had before whitening your teeth. In a nutshell, the PAP+ formula is more effective at whitening teeth and does a better job of remineralizing the enamel. It also has additional benefits, including resolving sensitivity, among others. How Does Pap Teeth Whitening Work? There are three primary solutions used for teeth whitening: hydrogen peroxide, carbamide peroxide, and PAP. They all work similarly, breaking down stain-causing molecules, hence lightening tooth appearance. This happens during a chemical process called oxidation. The bleaching agents enter through the enamel (protective layer of the tooth), altering and breaking down the molecules that hold the tooth’s color. While both PAP and the peroxides work similarly, there’s a slight difference. When whitening using peroxide-based teeth whitening treatments, they release free radicals. These free radicals attack organic molecules hence reducing discoloration. However, they also cause unwanted side effects, which may lead to sensitivity, gum irritation, and demineralization. PAP similarly reacts with tooth stains. However, it does not release free radicals. This means that while safely breaking down the molecules that cause discoloration, there isn’t any risk of teeth whitening side effects, such as sensitivity, irritation, or pain.