This brief tutorial will show you how to reinstall a package using apt-get in command line in Ubuntu.
Below content are from apt-get man page
j@j-ubuntuman:~$ apt-get|grep reinstall -A5 --reinstall Re-Install packages that are already installed and at the newest version. Configuration Item: APT::Get::ReInstall.
So I think you should know you can reinstall a package use apt-get with –reinstall option
sudo apt-get install --reinstall package-name
Optional ,you also can remove the package then install it again in some special case
sudo apt-get remove package-name sudo apt-get install package-name