Hematoma, which is often caused by excessive and fast injection at the location causes the capillaries to rupture and gather beneath the subcutaneous space. The color could change from purple to red and appear as a bruise. Its only treatment is an immediate cold compress and a hot compress the day after along with comforting the parents and the baby. By one week, the problem will disappear. Always inject calmly during supraperiosteal injections, especially for the D tooth. Convince the child not to make sudden moves so that the injection is not rushed. Always pressure the injection area and the buccal vestibule with a finger or a cotton roll toward the eyes to avoid hematoma and allow the anesthetic to spread.