Question

One of the concerns about plastic surgery on adolescents is that their bodies are still maturing. In addition to development that may occur in the late teens. This is why plastic surgery shouldn't be introduced teens this is because they have little knowledge about this concept they totally don't know what will happen after the procedure.
is this correct check my grammar

Answer 1

Second sentence doesn't make sense. Third sentence is three sentences run together.

Answer 2

Please study this:

http://grammar.about.com/od/rs/g/runonsentenceterm.htm