A medical, in particular dental, cutting tool which is drivable by sound, comprising: a connecting part for connecting the cutting tool to a sound source, a lamellar working section and a shaft connecting the connecting part to the lamellar working section, wherein a liquid line extends through the shaft up to the lamellar working section and wherein the lamellar working section comprises two side faces (4A, 4B) arranged essentially parallel to one another and a peripheral edge connecting the two side faces (4A, 4B), wherein a plurality of cutting elements in the form of teeth are provided on the peripheral edge, wherein at least one tooth comprises a base connecting the latter to the lamellar working section, a tip, a first side face formed by the first side face of the lamellar working section, a second side face formed by the second side face of the lamellar working section, and cutting faces (9E1, 9E2) arranged between the side faces (9C, 9D) of the tooth, wherein the cutting faces (9E1, 9E2) have a first inclination from the base in the direction of the tip, characterized in that at least one cutting face (9E1, 9E2) has a second inclination starting from one side face (9C, 9D) of the tooth in the direction of the other side faces (9C, 9D) of the tooth, so that the at least one cutting face (9E1, 9E2) is arranged at an angle deviating from a right angle to the side faces (9C, 9D), wherein the lamellar working section is connected to the shaft via a connecting section, wherein the connecting section comprises an outside dimension that increases in the direction of the shaft and wherein the side faces (4A, 4B) of the lamellar working section are continued in the connecting section, wherein a plurality of openings, for example, two openings, are provided on the connecting section which form the ends of the liquid line and through which fluid from the fluid line is dispensable onto the lamellar working section and the treatment site, and wherein the lamellar working section has a portion with a largest width which has an apex, wherein the width of the lamellar working section tapers from the apex in the direction of the front end of the lamellar working section and in the direction of the shaft, wherein some of the cutting elements in the form of teeth are arranged on the section of the lamellar working section that tapers in the direction of the front end, and some of the cutting elements in the form of teeth are arranged on the section of the lamellar working section that tapers in the direction of the shaft. a connecting part for connecting the cutting tool to a sound source, a lamellar working section and a shaft connecting the connecting part to the lamellar working section, wherein a liquid line extends through the shaft up to the lamellar working section and wherein the lamellar working section comprises two side faces (4A, 4B) arranged essentially parallel to one another and a peripheral edge connecting the two side faces (4A, 4B), wherein a plurality of cutting elements in the form of teeth are provided on the peripheral edge, wherein at least one tooth comprises a base connecting the latter to the lamellar working section, a tip, a first side face formed by the first side face of the lamellar working section, a second side face formed by the second side face of the lamellar working section, and cutting faces (9E1, 9E2) arranged between the side faces (9C, 9D) of the tooth, wherein the cutting faces (9E1, 9E2) have a first inclination from the base in the direction of the tip, characterized in that at least one cutting face (9E1, 9E2) has a second inclination starting from one side face (9C, 9D) of the tooth in the direction of the other side faces (9C, 9D) of the tooth, so that the at least one cutting face (9E1, 9E2) is arranged at an angle deviating from a right angle to the side faces (9C, 9D), wherein the lamellar working section is connected to the shaft via a connecting section, wherein the connecting section comprises an outside dimension that increases in the direction of the shaft and wherein the side faces (4A, 4B) of the lamellar working section are continued in the connecting section, wherein a plurality of openings, for example, two openings, are provided on the connecting section which form the ends of the liquid line and through which fluid from the fluid line is dispensable onto the lamellar working section and the treatment site, and wherein the lamellar working section has a portion with a largest width which has an apex, wherein the width of the lamellar working section tapers from the apex in the direction of the front end of the lamellar working section and in the direction of the shaft, wherein some of the cutting elements in the form of teeth are arranged on the section of the lamellar working section that tapers in the direction of the front end, and some of the cutting elements in the form of teeth are arranged on the section of the lamellar working section that tapers in the direction of the shaft.