Hello! A dentist spotted resorption on my routine dental X-ray and referred me to an endo, who said I have external resorption, rather than internal, and nothing further can be done, from his perspective. I have no symptoms, but the endo said the tooth could fail at any time, months or years. Would extraction (and subsequent implant) now be the best course of action? See my X-rays attached. Any idea about what stage on the Heithersay scale my case would be? Also, what is the predominant theory on what causes resorption? I have had no trauma to the tooth but did have braces as a teen. Thank you!