Dental impression compounds and plaster-based dental preparations are regulated as Class II medical devices by the FDA. Importers must ensure the foreign manufacturer is registered with FDA, that the device is listed, and that it meets applicable performance standards. Shipments may be subject to FDA examination at the port of entry.

Both fall under the single subheading 340700, so there is no tariff-line distinction between them. However, the regulatory treatment differs significantly: modeling pastes for children are not subject to FDA device regulation, while dental impression compounds are. The product's intended use and labeling determine which regulatory regime applies, even though the HTS classification is the same.