Custom bleaching trays (trays fabricated by a dental laboratory or in a dentist’s office) can have features designed into them that are not possible with store-bought whitening trays. One such design feature is “bleach reservoirs.”

The term bleach reservoir (or whitener reservoir) refers to a small space that is purposely allowed to exist between the inside surface of the whitening tray and the front side surface of the teeth that the tray covers. When the bleaching tray is filled with whitening gel and then seated in the patient’s mouth, a small excess of whitener will be retained in each reservoir and held in intimate contact with its adjacent tooth.

Are whitener reservoirs really necessary?

The need for bleaching tray reservoirs is still a point of debate among dentists. There has been scientific evidence published that supports both sides of this argument.

It is probably most accurate to suggest that the maximum whitening endpoint that a patient has the potential to achieve with at-home whitening treatments will be exactly the same whether or not the bleaching trays that they use have reservoirs incorporated into them or not. But it is most likely that this endpoint can be reach more rapidly if whitener reservoirs are present.

There is a caveat here. This last statement would most accurately describe those situations where the patient’s whitening regimen involves relatively longer individual bleaching treatments (as an example, four hours of wear using a 10% carbamide peroxide whitening gel). For shorter bleaching time frames, the benefit of reservoirs may not be as significant.

What are the recommendations of tooth whitening gel manufacturers?

The following evidence may help to make the case that bleaching tray reservoirs could be considered to be optional. The following list contains the names of many of the different whitening gel products that are marketed directly to dentists for use with their tray bleaching patients. We’ve separated these names in to two groups according to whether or not the instructions provided for the dentist suggest that the use of tray reservoirs is an important factor associated with the use of their product. Certainly not all of them do.

Tray reservoirs recommended.

Sapphire Take Home, GC TiON Take Home, Pola Day, Pola Night, Opalescence PF

Tray reservoirs optional.

Beyond StayWhite, Nupro White Take Home, Discus Dental NightWhite, Discus Dental DayWhite, Zoom! Weekender, Natural Elegance Plus, Venus White, Life-Like Cosmetic Solutions, Omni White & Brite, Perfecta Bravo, Perfecta Rev, Star White

How are bleaching trays with reservoirs fabricated?

Whitener reservoirs can only be incorporated into the design of custom bleaching trays (trays fabricated in a dentist’s office or by dental laboratory). Even with trays that are user modified, there simply isn’t any way to create bleaching reservoirs in store-bought whitening trays. Here’s a description that outlines the way dental laboratories fabricate trays with reservoirs.

• The dentist takes an impression of the patient’s teeth and mouth and sends it to the dental laboratory. A lab technician fills the impression with plaster so to create a cast. This is the cast on which the patient’s whitening trays will be made.

• The laboratory technician will apply and then cure a thin layer (about .5mm) of liquid plastic on the front side of each individual tooth on the cast (especially the front ones where the bleaching effect is most desired). This plastic represents the actual volume of whitener that the dentist wants held against the tooth, as well as its location.

• A heated sheet of plastic is then vacuum-molded over the plaster cast. The plastic spacers that were applied will hold the space for the individual reservoirs. The whitening tray is then removed from the cast and trimmed, as is needed, so it fits comfortably and accurately in the patient’s mouth.