Question about my iPhone 3gs?

[Reggie H]

Ok I change my damage screen that I cracked earlier.it works find the only problem is I can't hear anything out my phone.When I make a call I don't hear it dial out nor hear people voices,the only way I can talk to someone is putting it on speaker phone,and putting in head phones.I may have damage a part while replacing my front panel and digitizer screen.Would you know what part I need to buy so I can replace it???I'm thinking the ear piece but I'm not sure.Thankyou