Sorry about your dog...it is the result fo to much energy. Labs come in two types one tha lay around and ones that have energy..all the chewing is a result of to much energy...I have a lab and walk him twice a day!!!for a total of almost an hour. I had problems til I started...It either walk him...or put up with goofy stuff like this. I know everybody is busy but if he is important you need to make time for him. maybe split it up amongst people. train him on a treadmill...If he is tired he won't miss you at all during the day. He will sleep all day and wake up 1hr b4 you get home.