An antimicrobial oral care composition effective against dental plaque, calculi, gingivitis and periodontal disease comprising (a) a cationic antimicrobial agent selected from one or a mixture of quaternary ammonium salts that are pyridinium compounds, (b) an anti-stain agent comprising one or more materials from each of at least two of the following chemical groups: (i) Group 1 anionic agents having a molecular weight of 15,000 or less and which are selected from a pyrophosphate salt； phytic acid or salt thereof； D-fructose-1-6-bisphosphate； D-ribose-5-phosphate； dihydroxyacetone phosphate； D-erythrose-4-phosphate； glycerol phosphate； creatine phosphate； D-ribose-5-phosphate； D-fructose-6-phosphate； D-xylose-5-phosphate； glyceraldehyde-3-phosphate； -D-glucose-6-phosphate； -D-glucose-1-phosphate； uridine-5-phosphate； ascorbyl phosphate； carboxymethyl dextran； dextran sulfate； carboxymethyl hydroxypropylcellulose； carboxymethyl methylcellulose or carboxymethyl starch. (II) Group 2 aldehydes, ketones or other compounds with reactive carbonyl or (III) Group 3 non-ionic ethoxylated surfactants, wherein the Group 3 anti-stain agents comprise ethoxylated linear alcohols having 18 or more carbons in the alcohol chain, 35 or more ethoxy units and an average molecular weight of about 2000 to about 15,000, and (c) a pharmaceutically acceptable carrier, wherein the anti-stain agent is present in an amount effective to inhibit the formation of dental stains caused by the cationic antimicrobial agent.Una composición para el cuidado bucal antimicrobiana eficaz contra placa dental, cálculos, gingivitis y enfermedad periodontal que comprende (a) un agente antimicrobiano catiónico seleccionado de una o una mezcla de sales de amonio cuaternario que son compuestos de piridinio, (b) un agente antimanchas que comprende uno o más materiales de cada uno de al menos dos de los siguientes grupos químicos: (i) Grupo 1 agentes aniónicos que tienen un peso molecular de 15.000 o menos y que son
