Abstract: The method for making an interdental brush inserts a bristle stem into a through hole of a handle in a combining step, whereby exposing the stem to each fixing slot on the handle. Thence the stem is further punched by a punching device, allowing a correspondent formation of expanding portions. Hereby, the expanding portions have an outermost diameter larger than an opening of the through hole for the stem to be firmly lodged in the fixing slots in a fixing step. A filler for wrapping the entire handle and the stem offers a solid engagement between the expanding portions and the fixing slots, so that the stem does not depart from the handle while using.

Abstract: The method for making an interdental brush inserts a bristle stem into a through hole of a handle in a combining step, whereby exposing the stem to each fixing slot on the handle. Thence the stem is further punched by a punching device, allowing a correspondent formation of expanding portions. Hereby, the expanding portions have an outermost diameter larger than an opening of the through hole for the stem to be firmly lodged in the fixing slots in a fixing step. A filler for wrapping the entire handle and the stem offers a solid engagement between the expanding portions and the fixing slots, so that the stem does not depart from the handle while using.