Which product is used for tray applications and should be avoided in patients with restorations?

• A. Gel or Foam 1.23% APF used in tray
• B. Gel 2% Naf fluoride
• C. OTC Fluoride Toothpaste
• D. Rx Fluoride Rinse

Answer: (A)

Tray fluoride therapy uses fluoride gel or foam delivered in a tray to maximize contact with the teeth. This often uses acidulated phosphate fluoride (APF) at 1.23%, which has a low pH that helps fluoride uptake by enamel. However, that acidity can attack restorative materials such as composites and porcelains, causing surface roughening, discoloration, or micro-pitting. Because of this risk, APF gel or foam used in trays should be avoided in patients with restorations. Safer alternatives for those patients include neutral pH fluoride gels like 2% sodium fluoride, fluoride varnish, or fluoride rinses, which provide protection without damaging restorations.