I have a 1 and a half year old Male Rhodesian Ridgeback and in the past 2 months his lip and gum is changing color from black to a whitish-red. I have taken him to his vet but the vet just said it's pigmentation. I am not sure about that and am considering a second opinion from another vet. It just doesn't look right. I have read articles which suggest taking away rubber/plastic toys and bowls which I have done for the past week.
Please see the below picture
Before(approximately 4 months ago)
Has anyone had this with their dogs or have any suggestions?