A 5-year-old girl is brought to the clinic 3 days after a traumatic injury. The guardian reports she lost a tooth. Tooth E (primary maxillary right lateral incisor) is mobile, and a gingival swelling is present near the area. A radiograph shows the permanent successor (#7) is in close proximity just apically. What is the most appropriate treatment?

In this case, tooth E is mobile following trauma (luxation injury), with a gingival swelling (infection/abscess) appearing 3 days post-trauma, indicating irreversible pulp damage or infection. The radiograph confirms the permanent successor is in close proximity. Key decision principles for traumatized primary teeth: (1) If the primary tooth is infected or non-salvageable and poses a risk to the permanent tooth, EXTRACTION is indicated. (2) A mobile, luxated primary tooth in a 5-year-old is not amenable to stable splinting. (3) The proximity of the permanent successor means infection from the primary tooth can directly damage the developing permanent tooth. Extraction eliminates infection, protects the permanent successor, and avoids further trauma. Monitoring is only appropriate when the tooth is stable with no signs of infection.