Patient: Description of condition (onset, main symptoms, hospital visited, etc.): I have worn down the enamel on the lower part of the crown due to incorrect brushing and brushing too hard, do I need to repair it with nano resin? What is the effect of the repair? How long will the restoration material last? The repair of enamel wear on the lower part of the crown depends on the degree of enamel wear and the situation. Small enamel wear can be repaired with nano-resin. The effect can be. The duration of use depends on the size of your chewing force. Large and severe enamel wear cannot be repaired with nano-resin, but can be repaired with inlays. Consider a full crown restoration for serious cases affecting the dental nerve.