Just remember that you can only claim relief on unrecovered medical expenses i.e. your medical expenses for which you cannot receive any further reimbursement.
AFAIK you still cannot obtain relief on routine dental treatment such as fillings, examination or scaling/cleaning. Other dental work like crowns is eligible for relief.
On the dental treatment I've always taken the simple approach that only expense treatments are available for claims for medical expenses. I ask the dentist for a Med 2 and if this is provided then you can claim relief. Most of the terms on the Form Med 2 aren't clear to me (as I'm not a dentist).