Check the remote control for its infrared emission. Check it with fresh batteries. If it is found OK, check and replace the infrared sensor inside the TV. If you wish to get some details; check the site linked here. It has details about how to check a remote control; by one among the post. Surf the site with patience. Pull up older posts. http://electronicshelponline.blogspot.com/
If some button/s seems do not respond, it will be best to buy an other remote control, rather than repairing this damaged one.