Bulge on face after dental implant. It's been 6 months. What can I do?

6 months ago, I got a dental implant (the lower part only) on tooth # 30 with bovine bone grafting. I still haven’t got the crown on. My dentist told me that my face would be swollen for 3-4 days after the surgery, and it did. Then the swell reduced and everything went back to normal except one thing. There is still a little bulge on my left cheek that won’t go away and it’s been about 6 months since the implant surgery. The bulge is not obvious. It doesn’t hurt no matter how I touch it. Help.