Opalescence 20% Carbamide Peroxide Whitening Gel, 8 Syringes

Syringes: Opalescence 20% Carbamide Peroxide Teeth Whitening Gel is a syringe refill for use with whitening trays, aligners, retainers, or Invisalign trays. The listing says wear it for 2–4 hours daily and claims whitening of up to 10 shades in 7 days. Trays are not included.

At a glance

Listing describes the gel as sweetened with xylitol and gluten-free and kosher.
The product is described as made in the USA by Ultradent Products.

Price

$53.99Save 16%

Reference price: ~~$64.00~~

Price checked: Nov 14, 2026

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Often bought together

Opalescence 35% Teeth Whitening Gel Refill Syringes (4ct) -5197-2 | 35% Carbamide Peroxide Whitening Gel for Custom Trays. Low-Sensitivity Formula, Mint, Dentist Developed Made in USA.

$34.00

Pros and cons

Pros

Eight individual syringes allow measured gel application to compatible trays.
The listing says no LED light is needed or recommended.
Compatible with several types of trays and aligners, though none are included.

Cons

A suitable tray is needed for use and is not included.

Technical specifications

8 specifications

Formula and use
Active ingredient strength	20%
Wear time	2-4 Hours a day
Compatible trays	Invisalign trays, aligners, retainers, and custom dental trays (none included)
LED light	NO LED Light Needed or Recommended

Contents and product details
Syringe quantity and volume	8x 1.2 ml Syringes
Dimensions and listed weight	6 x 3.5 x 1 inches; 1.2 ounces
Model number	5370-U
Manufacturer	Ultradent

What to know before buying

Listing details to confirm

The listing claims whitening of up to 10 shades in 7 days, but results are not guaranteed. Customer feedback reports that the 2–4-hour wear period can feel lengthy and includes mixed reports of sensitivity and gum irritation. Check the product expiration date and condition on arrival, as some customers report receiving expired or dried-up gel. The title gives code 5196-4 while product details list model 5370-U, so confirm the selected item and model before ordering. The listing's compatibility claims do not confirm that every tray or aligner is suitable for every user.

Who is it for?

A good fit for

Buyers who already have compatible trays or aligners and want syringe-applied whitening gel.
People looking for a 20% carbamide peroxide formula with a stated 2–4-hour daily wear time.

Less suited to

Buyers who need trays included or cannot accommodate several hours of daily wear.
People seeking a whitening product that avoids possible sensitivity or gum irritation.

Opalescence 20% Carbamide Peroxide Whitening Gel, 8 Syringes · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.5 / 5 · 5,412 ratings

5 stars77%77%
4 stars12%12%
3 stars5%5%
2 stars2%2%
1 star4%4%

Customer feedback describes the gel as easy to use and effective for whitening, with some reports of visible change after two nights. Experiences with sensitivity and gum irritation vary, and the stated 2–4-hour wear time is a concern for some. Reports of expired or dried-up product make checking the date and condition especially relevant. These are customer perceptions, not guarantees of results or evidence that every package has the reported issues.

Positive themes

Customers report noticeable whitening and ease of use.

Negative themes

Some customers report receiving expired or dried-up product.

Mixed feedback

Reports about tooth sensitivity and gum irritation vary, from little discomfort to burning sensations.
Some customers consider the 2–4-hour application time lengthy.