Name the injury seen in the colour plate:

A crack line or chip of the enamel is the key clinical feature of enamel infarction. ENAMEL INFARCTION CLINICAL FINDINGS: Visual examination by DYES (Methylene Blue). Tooth is not tender on percussion. If tender on percussion, check for luxation injury/root fracture. TREATMENT: Etching and sealing with resin to prevent discoloration of infarction line.