An aqueous chemical mechanical planarization polishing composition comprising a dispersion of a plurality of elongated, bent or nodular colloidal silica particles which contain a cationic nitrogen atom, and from 10 to 500 ppm of a cationic copolymer of a diallyldimethylammonium salt comprising a copolymer of a diallyldimethylammonium halide salt and sulfur dioxide, wherein the composition has a pH of from 1 to 4.5 and, further wherein, the amount of the dispersion of the elongated, bent or nodular colloidal silica particles, ranges from 0.5 to 30 wt. %, all weights based on the total weight of the composition.