This question was originally raised in 2006. Since then, more studies into over-the-counter products like Anbesol and Orajel have been conducted. Here’s a link to the article: http://thechart.blogs.cnn.com/2012/06/01/fda-warns-about-benzocaine-in-baby-pain-gels/?hpt=he_c2
As with most over the counter products, they should be used according to instructions, and not more than recommended. Doing this will limit the potential for side effects. Using Anbesol/Orajel sparingly and for short periods will likely not cause the methemoglobinemia discussed in the article. However, the potential is there — so if there is any question, contact your doctor.