10 октября, 2015 
Malyar The compositional and performance features of the zinc oxide-eugenol and zinc oxide- ortho-ethoxybenzoic acid cements were dealt with in Sections II. B.3 and II. B.4. While employed for temporary luting and filling, the ZOE materials find their major use in cavity lining. The fundamentally weak cement materials are usually reinforced for this
purpose with poly(methyl methacrylate) filler in powder form, and compressive strengths of 40 to 50 MPa can thus be attained. The rather high degree of solubility and eugenol leaching, presenting a drawback in luting applications, can be tolerated for lining purposes even in deep cavities, where use of the phosphates is contraindicated. Occasionally, therefore, ZOE cements are placed as sublinings to be overlaid with zinc phosphate. They are not useful, however, as liners under resin-based restorations because free eugenol may interfere with the free-radical polymerization hardening of the resin filling materials.
Although employed predominantly as luting agents, the EBA cements, because of their high silica filler content (ca. 35%), are more resistant to flow in the uncured state, and possess higher compressive strength (80 to 85 MPa), than the ZOE cements. Therefore, they provide a useful lining function, notably under amalgam. As in luting applications, the bonding effects of both ZOE and EBA materials toward dentin and restorative are of the micromechanical mode and hence are quite weak.
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