A custom tool for forming a dental restoration in a mouth of a patient includes a mold body providing for a customized fit with at least one tooth of the patient. The mold body includes a facial portion forming a facial surface corresponding with a facial surface of the tooth, and a separate lingual portion forming a lingual surface corresponding with a lingual surface of the tooth. The mold body is configured to combine with the tooth of the patient to form a mold cavity encompassing missing tooth structure of the tooth.