Explanation: The vermillion border of the lip is a thin white line that separates the lips from the face. A laceration with even 1 mm of misalignment through the vermillion border will be instantly noticeable at arm’s length, so perfect alignment is needed during the repair. The benefits and risks of chemical sedation should be weighed for any repair of the vermillion border, as helping younger children remain still improves the safety of the procedure and the cosmetic outcome of the repair. A regional block is recommended for analgesia, as it is less likely to obscure important structures, and it can reduce the amount of chemical sedation administered. For the outer lower lip, an injection of lidocaine with epinephrine near the mental nerve (e.g., mental nerve block) is the most appropriate regional block. Older children might be cooperative enough for a regional block without chemical sedation, especially intraoral attempts after the application of a small amount of topical lidocaine to the injection site. The first suture in the repair should be a 6-0 nonabsorbable suture at the vermillion border with perfect approximation. The mucosal surface can then be closed with 5-0 absorbable material, and the skin closed with 6-0 nonabsorbable material. Inhaled nitrous oxide (A) can be used as an adjunct to a regional block, but it will obscure the suturing site if a facial mask is needed and will not result in analgesia. Locally injected lidocaine with epinephrine (B) will result in blanching and swelling of nearby tissues, obscuring the vermillion border and resulting in an inferior repair. Topical lidocaine-epinephrine-tetracaine (D) should not be applied to mucosal surfaces due to systemic absorption of lidocaine and epinephrine.