Trying to fill in some blanks in understanding some of the HPV information presented. What (if any) is the difference between HPV 16 and HPV 18? Are both found in Oral cancer?

Thanks,

Nancy
Age 56 at diagnosis
Neck Lymph node removed 11/2012
Tonsillectomy perfomed 12/2012 - identified as primary
SCC Left Tonsil with Left Node involvement, DX 12/2012
RX started 1/29/2013, finished 3/23/2013;
Daily IMRT (35 Sessions)
Weekly Taxol/Carboplatin (6 weeks)
PEG placed after week 4 (3/1/2013)
PEG removed 6 1/2 months later (8/12/2013)