THE REACTION OF METAL OXIDES WITH o-ETHOXYBENZOIC ACID AND OTHER CHELATING AGENTS

¹ Dental Research Section, National Bureau of Standards, Washington 25, D. C.

Mixes of zinc oxide with many compounds capable of forming chelates result in coherent products. Mixes containing o-ethoxybenzoic acid, salicylaldehyde, acetylacetone, o-ethoxyacetic acid or lactic acid form hard products within 1 hour at room temperature. Some of these products disintegrate in water.

EBA and oxides of group IIB and those tested in group IIA of the periodic table as well as lead oxide harden rapidly.

Solutions of EBA and eugenol, when mixed with zinc oxide, have a short setting time. The products show a marked increase in compressive strength. Water solubility and density of the product increase.

Addition of quartz powder further improves the physical properties of the hardened material.

The products may be of interest as dental impression pastes or temporary fillings.