Thats because I used a stone to smooth it and didn't use 25k rpm die grinder lol. Should the radius on this be smaller? Honestly for that I've been putting the burr straight in the corner like this, because it was pretty close to the same size. But I have had a problem getting the bur to come straight out and keep that vertical line straight, so then I just start bowing it out. Grinding a tooth is different. My dental handpiece is small, smaller than the air die grinder. My burr is 1-1.5mm wide. I do have cross cut fissure burrs and all the different shapes like you can get for these big ones. I also run my dental burrs at 200k rpms and with water. Most of my cuts on a tooth are less than .5mm if I'm trying to smooth a wall or a floor of a tooth where I'll be placing a filling. My smallest width burr is .1-.2mm wide and my widest is 1.5-1.8mm. Oh also I wear loupes, which are like magnifying glasses attached to my eyes and I have a constant light. Not having a good light source while cutting on the heads definitely makes grinding them a little harder. I've actually been looking for my extra head light to wear while cutting, but I havent found it yet lol. Per the tooth, even at 200k rpm, it is pretty though to cut, but once you get past the outer layer it cuts much easier. Which is different from the cast iron, which cuts the same no matter how deep you get.