Its far to premature to even conclude that inhaled nicotine protects the lungs. This is just one study. Don't do anything stupid, like go develop a nicotine addiction, just because of one headline.
Obviously I would never think of suggesting that people start smoking tobacco. My comment was meant to discourage people from leaping to conclusions and getting addicted to nicotine lozenges when, as far as I know, there is little that suggests they'd be beneficial.