Soothely
Six studies, plainly summarised, including the ones that were not flattering.
PAP is newer than peroxide, which means the evidence base behind it is thinner and younger. Here is an honest read of what exists, including the findings that do not help our case.
Across every comparison we could find, PAP formulations produce markedly less post-treatment sensitivity than peroxide at comparable whitening outcomes. This is the most consistent result in the literature and it is not really disputed. Where trials report sensitivity as a secondary outcome, the PAP arm reports fewer incidents and lower severity almost without exception.
On raw whitening speed over a two-week window, several studies put high-concentration hydrogen peroxide ahead. If your only measure is shades per day and sensitivity genuinely does not bother you, peroxide is still the faster route. We would rather say that plainly than pretend otherwise.
There is also a real methodological problem in this field. A lot of the PAP work is small, industry-funded, or conducted on extracted teeth rather than in mouths. Extracted-tooth studies are useful for mechanism but they tell you nothing about saliva, diet, or how a person actually uses the product over fourteen days.
The honest summary: PAP is clearly gentler, probably slightly slower, and studied less thoroughly than peroxide. Anyone claiming it is definitively better on every axis is ahead of the evidence.
Several papers have looked at surface microhardness and roughness after treatment. Peroxide consistently reduces microhardness measurably in the short term, with recovery over subsequent days as saliva remineralises the surface. PAP shows little to no reduction in the same tests. Where a remineralising agent such as hydroxyapatite is included, some studies show a net improvement in surface condition.
Our own figure is a median shift of 3.1 VITA classical shades across 218 customers who submitted a start photo and a day-14 photo. That is not a controlled trial. Photos vary in lighting, people self-select into sending them, and nobody was supervised. It is a real number from real customers, and it is also a weaker form of evidence than a randomised trial. Both of those things are true at once.
Nobody in that group reached B1, the lightest tab on the classical scale, in a fortnight. If a whitening product promises you B1 in two weeks, that promise is the thing to be suspicious of.
Ask three questions. What was the sample size, and were participants supervised. Was the comparison against a placebo or against another active product. And was the shade change measured on a standard scale by somebody who did not know which group the participant was in. Most marketing claims fail at least two of those.