Hi Mark. The eyes need a specular highlight - See "Part 8: Finishing up the Scene" - https://sites.google.com/site/digitalmcguffin/pipeline-1-texturing-page-1
Also, the turnaround video is uploading now...https://sites.google.com/site/digitalmcguffin/pipeline-1-turnarounds
Hi Mark - I just had a thought. Do you have an 'ambient occlusion' node plugged into the teeth shader? If so you can remove it and just increase the ambient channel itself to brighten the teeth. It may be why you're seeing a black mark.