Crown lengthening is a commonly performed surgical procedure in dental practice. Surgical guides assist clinicians to establish appropriate soft and hard tissue architecture. Herein, a new classification of surgical guides for crown lengthening is introduced in the present study. According to the features of the length indicator unit (LIU), the surgical guides are classified as three types. Type I, LIU indicates the planed gingival margin at the tissue level. Type II, LIU indicates both the planed gingival margin and alveolar crest at the tissue level. Type III, LIU indicates the planed gingival margin at the tissue level and the alveolar crest at the bone level, respectively. Schlagwörter: Dental esthetics, crown lengthening, gingivectomy, alveolectomy