A method of making a trim article includes the steps of 1) obtaining specified criteria of a target component part comprised of a plurality of materials; 2) processing the specified criteria into a design envelope that includes parameters of the target component part within which the trim article to be created is to be confined, 3) inputting the design envelope into an additive manufacturing device supplied with a single forming material; and 4) forming the trim article using the additive manufacturing device from the single material. The formed trim article includes an outer casing with an interior portion having one or more lattice matrices disposed therein and having varying density profiles to simulate the specified criteria of the target component part. The formed trim article is created as a fully integrated monolithic whole via the additive manufacturing device.