Remove item from combo box once it's been selected

Question

I have a textbox ,a button named insert and  a combobox .The comboBox loads data from the database.What I would like to do is to remove data from the combobox if the selected data has been inserted once. Let's i have data loaded in the combobox from the  database are Alex, Ronok, Jonny and so on.In the textbox i put 1 and select Alex for that from combobox loaded data.Now insert it into the database using insert button.When the next time the combobox loaded the  combobox item Alex disappears.How can i implement it using stored procedure.Please help me to solve it.Thanks in advance.