There have been several incidents in the news about pedicures (and manicures) leading to serious infections because of contaminated instruments. Those infections are even more serious for diabetics but anyone can be infected. The medical community says to make sure your manicurist sterilizes the instruments. An article I read also suggested that they not cut the cuticle around the nail because that can introduce bacteria. They can just push the cuticle back instead of cutting it away. If I were you, I'd also ask my physician about it.
Jeannie, is it possible that the thickened nail is the result of nail fungus? A home remedy for that and hopelessly calloused heels is Vicks Vapo Rub. Recent medical columns I read said that feet callouses may also be fungal infections and regular creams don't help that much. I don't have nail fungus but I did have terrible heel callouses. No medicines or creams worked except the vapo rub which also softens nails. Just a thought.
Yes, exactly, Ruth. I'm sorry if I was misleading. I think my comment evolved from diabetic caution with pedicures to just a home treatment for callouses on the feet - I didn't mean to imply they had to do with diabetes.