In vitro tensile bond strengths of about 1 ton per square inch between composites and dentin and enamel were obtained by applying a 5.3% solution of ferric oxalate to the tooth surface, followed by water and air cleaning; by applying a 10% solution of NTG-GMA, followed by cleansing with solvent and air; by applying a 5% solution of PMDM, followed by air to remove the solvent; and by placing the freshly mixed composite against the treated surface. If this breakthrough in the laboratory leads to sufficiently durable adhesion in clinical practice, the conservation of retention-form dentin could increase patient comfort, reduce treatment time and cost, and lessen fatigue for dentists.