Does Hismile PAP+ Work to Whiten Teeth? Hygienist Explains


Teeth whitening is one of the top topics brought up in my dental chair. My patients always ask me about teeth whitening products or the best products to use if they have sensitive teeth. I’ve had patients ask me about the Hismile PAP+ teeth whitening they have seen advertised online and if the product will work to whiten their teeth.

Hismile PAP+ teeth whitening products do whiten teeth. PAP (phthalimido peroxy caproic acid) oxidizes intrinsic stains embedded within the tooth structure, changing the colour of the teeth. PAP causes less tooth sensitivity than hydrogen or carbamide peroxide, making it a good option for whitening.

A photo of the Hismile PAP+ teeth whitening strips that I purchased.

PAP, short for phthalimido peroxy caproic acid, is present in many household items, including laundry detergent. In recent years it has started to be used in teeth whitening products.

In this post, I explain how PAP whitens teeth, including evidence-based science, if PAP is better than using traditional hydrogen/carbamide peroxide, and tips and tricks that I tell all my patients who are interested in whitening their teeth.

I made a video of me using this product and included it below! I do the entire full treatment (14 sessions) and track my progress with a teeth shade guide to see how much whitening I got! I go over a lot of important information regarding teeth whitening, strips and this product specifically! Enjoy!

Before I go on, it is essential to note that I am not paid by Hismile or affiliated with them. I purchased this product with my own money (and I even spent an absurd amount on duty charges upon delivery) and did copious amounts of research to give you an unbiased review and the latest evidence-based science on the product's efficacy. 

PAP+; How does phthalimido peroxy caproic acid whiten teeth?

The stain molecules need to be oxidized for the tooth structure to change colour physically. When the stain molecules are oxidized, and the stain is removed, it changes how the human eye interprets the colour of the teeth by changing how light refracts and reflects off the teeth.

The Hismile PAP+ sparked my interest mainly because the claim is that the product will not cause tooth sensitivity, one of the biggest complaints associated with teeth whitening.

There is strong evidence that this product will whiten teeth and physically change the colour of natural teeth.

I have scoured the internet for high-level scientific studies of these products, and I found a few to be highly reliable, and the evidence is promising that PAP will work to whiten teeth. I linked one of those studies below and provided a quote from the study.

“The results showed that single-use bleaching containing a phthalimido peroxy caproic acid (PAP) agent yielded significant initial whitening compared to baseline and placebo. These results remained stable in time, e.g. 24 h after application.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5804394/ Opens in a new tab.

PAP+ is an extremely interesting technology, and I think will advance teeth whitening. When oxidation occurs when using PAP, no free radicals are formed in the reaction, unlike with the use of hydrogen/carbamide peroxide.

Free radicals are thought to be the main cause of irritation and sensitivity.

If you want to learn more about free radicals that occur in teeth whitening, below is a quote and a link to a study that explored free radicals in tooth whitening but also compared how hydrogen peroxide and PAP gels affect the surface microhardness of the teeth.

While both had similar bleaching effects on bovine teeth, surface morphology and hardness measurements of the bleached teeth revealed that the HP gel caused some reduction in surface microhardness, while the PAP-based gel did not affect the integrity of enamel.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8700120/#:~:text=Traditional%20dental%20bleaching%20using%20HP,structures%2C%20their%20optical%20properties%20change. Opens in a new tab.

Hismile is not up there on my top brands due to the misleading tactics of their advertising strategy and also promoting of products that simply do not have any effect on the pigment of the teeth, such as the Hismile V34. You can read the post linked below to learn all about the product and how the claims they make do not stand up to evidence-based science.

Read Now: Hismile V34; Dental Hygienist’s Non-Sponsored Review

However, the PAP+ teeth whitening strips they sell will safely whiten teeth, and I find it exciting that newer technologies are being discovered to avoid teeth sensitivity from teeth whitening.

Is PAP better than hydrogen peroxide? What I use as a dental hygienist

In Hismile’s PAP+ formula, they have added potassium citrate, which helps to desensitize the tooth’s nerves and nano-synthetic hydroxyapatite, which helps to remineralize the tooth after the whitening process.

All the evidence I have read points to PAP being an effective and safe way to whiten teeth and with fewer side effects (than traditional hydrogen peroxide), such as teeth sensitivity.

It is important to remember that this teeth whitening method has not been around for too long to determine long-term effects on the teeth and oral tissues.

Although, as I previously mentioned in this post, the evidence currently shows that PAP can be just as effective as hydrogen peroxide but with fewer side effects.

The main advantage of using PAP as a teeth whitening agent is the huge decrease in post-operative pain associated with teeth whitening. I have had patients contact me after their teeth were whitened because they were experiencing zingers and couldn’t bear it.

Read Now: Teeth Whitening Zingers: How to Prevent or Stop Sensitivity

In the below study, there was a very large difference between levels of tooth sensitivity when comparing PAP vs hydrogen peroxide.

In a test group using PAP, 83.3% of individuals had no teeth pain associated with the whitening treatment. In the test groups using hydrogen peroxide only 12.5% of individuals had no teeth pain associated to teeth whitening.

https://doi.org/10.1016/j.coco.2019.04.002Opens in a new tab.

As a dental hygienist, it is my duty to keep up with newer technology and methods of whitening teeth.

I bought the Hismile PAP+ whitening strips and am using them now. I will update this post with my firsthand experience and how many shades whiter my teeth got when I am done with my treatment. My teeth are already pretty white from whitening with peroxide gel in custom trays earlier this year, so my results may not be as drastic as some users.

Side note: I always look at evidence-based science to unbiasedly understand the product. It is not good to see Kim Kardashian endorsing a product and say, “yeah, I’m going to use that.” I want to know if the product is safe and effective to use, regardless of who is promoting it.

I wish that Hismile sent their products to dental professionals to review and be their influencers because it would provide a much more authentic and accurate review. Having mostly non-dental professionals trial their products do not allow for honest reviews.

Many people/influencers are thrilled to receive something free in the mail and are then encouraged to make a positive claim, even when the results are not calibrated properly.

Left side: Before the dental hygiene appointment, calculus is present on the bottom front teeth on the tongue side. Calculus is discoloured, appearing yellow and brown in colour. Right side: After the dental hygiene appointment and calculus has been removed.

What I tell my patients to do before starting teeth whitening treatments

A full check on your oral health and hygiene appointment before teeth whitening is very important.

If you whiten your teeth while there is still calculus (tartar), gum inflammation, or tooth decay, teeth whitening can cause detrimental effects and drastically reduce the effectiveness of teeth whitening.

Read Now: How Dental Hygienists Clean Teeth! What You Need to Know!

I don’t want you to spend money on a product and it not be effective.

If there is calculus (tartar) on the teeth, which is a calcified mass of bacteria and food debris that is bonded to the tooth (cannot be removed by flossing and brushing), the teeth whitening product will not penetrate the calculus.

If you whiten your teeth while having calculus, then you have the calculus removed. You may end up with a line on your teeth where the surface not whitened will stand out.

If there is a lot of gum inflammation, your mouth is not in the optimal state for teeth whitening. The gums will cover more tooth surface area when inflamed, reducing the surface area that is being whitened and can cause more gum irritation.

If there is tooth decay, sometimes it can take on a darker colour, possibly making you think your teeth are stained. Whitening teeth, while you have tooth decay can increase the pain from the cavity that can last days.

Also, if you have any fake tooth surface, such as a filling, crown, or veneer, the fake tooth surface will not whiten.

A photo of Sensodyne toothpaste.

If you get the all-clear from your dental professional to start whitening, you will want to use a toothpaste containing potassium nitrate for 2 weeks prior to beginning the whitening product.

Potassium nitrate will help desensitize the tooth’s nerve, decreasing post-operative tooth pain from teeth whitening.

There have been reports of tooth sensitivity after using PAP, so I don’t want people to think that it is a foolproof product that will never cause sensitivity. It is just a lot less than the traditional peroxide side effects.

Avoid teeth whitening products that come with lights

In the highest level of scientific studies, the lights used with dental teeth whitening do not work and will not make any difference in tooth shade that the naked eye can see. Please don’t buy their products that come with a light.

I wish Hismile would not sell the light for some of their teeth whitening products. It is such a waste and creates so much plastic garbage.


I hope you have found this information useful and have learned about PAP+ whitening.

Have a wonderful day,

Holly 🙂

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