Carious lesions with deep margins represent a challenge in daily clinical practice. The following key points are discussed in this article: how to manage a deep margin from a restorative point of view; when and how to perform a surgical procedure; and when it is favorable to carry out definitive restoration work after surgery. The restorative materials and adhesive procedures available today allow minimally invasive techniques to be used on dental tissue with a high preservation of tooth structure. These materials and techniques help to avoid adverse periodontal tissue reactions. Depending on the clinical situation, three treatment options are available when dealing with a subgingival margin. If the depth of the cavity margin is at a maximum distance of 1.5 mm below the gingival margin, isolation with rubber dam allows the performance of interproximal margin relocation, thereby facilitating optimal restoration and periodontal tissue integration. If the margin is located deeper than 1.5 mm below the gingival margin, surgery is necessary before any restorative work can take place. When the margin is within 2 mm above the bone crest, a supracrestal tissue esthetic management (STEM) procedure is undertaken, which means that no ostectomy is required and only osteoplasty is necessary to reshape the preexisting supracrestal attachment, thereby allowing the restorative work to proceed. When the margin is less than 2 mm above the bone crest, crown lengthening with minimal ostectomy and subsequent osteoplasty becomes necessary.