Figure 3.

A. Original photograph of a classic sodium hypochlorite accident taken from Witton and Brennan,⁴⁸ showing ecchymotic involvement of the eyelid and the angle of the mouth (3A reprinted with permission from the Nature Publishing Group). B. Superficial “digital dissection” based on Figure 3A, showing the superior and inferior palpebral veins and the superior and inferior labial veins. The facial vein in the middle third of the face is covered by the malar fat mad, associated adipose tissues and the zygomatic muscles. C. “Digital dissection” of the adipose tissues enables the underlying facial vein to be reviewed. An anatomical anomaly is presented in which the venule from top apical foramen of the upper right lateral incisor drains directly into the facial vein. D. Further “digital dissections” of the facial skin reveals the course of the facial vein and its tributaries in relation to the muscles of the face and neck. (3B–3D reprinted with permission from SybronEndo, Carlsbard, CA, USA).