Altered passive eruption is associated with esthetic problems due to incorrect teeth proportions. The crown lengthening procedure can be carried out only after the final position of the incisal margins is determined. In the case presented here, orthodontic treatment was carried out as a first step to realign the teeth. The surgical procedure was performed using a set of instruments designed by Chu (Chu's Esthetic Gauges, Hu Friedy). The desired length of the crowns of the teeth was visualized using a proportion gauge, followed by a gingivectomy. After dissection of the mucoperiosteal flap, the extent of osteoplasty and osteotomy required was assessed using the crown lengthening gauge. The distance from the bone edge to the enamel-cement junction should be approximately two mm. In the final step, the surgical flap was recomposed and stabilized. The last photo shows the clinical situation immediately after the procedure.