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Orthodontic Banding Cements

Despite the advent of bonded attachments, preformed stainless steel bands are still routinely utilized in fixed appliance therapy. Banding offers superior reliability due to better resistance to occlusal interferences (Fricker, 1997). Band cements are necessary for band retention, either by assisting mechanical retention or by true adhesion. They also serve to seal a band to a tooth, filling the irregular gaps to prevent stagnation areas. Zinc phosphate cement was widely used for band cementation for much of the last century. It has high compressive strength, but suffers from low tensile strength and high solubility, resulting in micro-leakage and demineralisation. Zinc polycarboxylate cements were introduced to orthodontics in the early 1970s and offered the advantage of chemical adherence to enamel. However, physical and handling properties were flawed, due to poor tensile bond strength, solubility, viscosity, and short working time. Both zinc phosphate and polycarboxylate cements have been superceded by new generations of adhesive cements, and are now largely obsolete as banding cements.