The quick answer is that kissing and mouth to skin contact (anywhere on the body) does not risk HIV, regardless of cankers or other sores in the mouth.

• 朋友，固然，我英文还将就，麻烦你还是翻译一下，我他妈强迫症了"亲吻，和嘴对皮肤的接触(任何部位）都没有，HIV的风险，不管有没有溃疡在嘴中麻烦你翻译一下"