How do I handle a long gap on my résumé? (update)

My résumé shows a gap from a layoff and some health issues. I worked as a dental hygienist before this. I am not sure how much to explain. How did you handle it on your résumé?

Thanks for writing this out. I went through something close to it 8 months ago, and it settled down once I kept a simple log of every call and form.