The most commonly used, most biocompatible and adhesive cement is:

The use of polyacrylic acid makes GIC capable of bonding to tooth structure. GIC is considered superior to many types of cements because it is adherent and translucent. Various formulas are available depending on the intended clinical application.   Water-soluble polymers and polymerizable monomers have been replacing part of the liquid content. Particles of metal, metal-ceramic, and ceramic have been added to some products to enhance mechanical properties. Other new formulations are capable of being chemically cured, light-cured, or both. GICs have been used for the esthetic restoration of anterior teeth, e.g., Class III and  V sites, as luting cements, as adhesives for orthodontic appliance and intermediate restorations, as pit and fissure sealants, liners and bases, and as core buildup materials. The GICs are classified below: Type I: Luting crowns, bridges, and orthodontic brackets Type IIa: Esthetic restorative cements Type IIb: Reinforced restorative cements Type III: Lining cements, base GICs elicit a greater pulpal reaction than ZOE cement but less than zinc phosphate cement. Glass ionomer luting agents pose a greater pulpal hazard than glass ionomer restorations when the GIC is mixed with a low P/L ratio because the pH remains acidic longer. With any GIC, a protective liner such as Ca(OH) 2 should be used if the preparation is closer than 0.5 mm to the pulp chamber. KEY Concept: The most commonly used, biocompatible and adhesive cement is Glass ionomer cement. Reference: PHILLIPS’ SCIENCE OF DENTAL MATERIALS, 12th ed page no 320, 323, 324