You can also sign up to a CX dental plan - rightchoice it's called and it's not too pricey. You get a free clean a year or maybe 2 but so far as real dental work goes, you get what you pay for!
On the subject of general medical cover, those with any dependants should seriously look at getting their own medical plan as the one the company provide you with is inadequate for family members. Sorry I don't have any details of what's available but BUPA have an office here and what you really need is gap insurance to bring dependant cover up to that of the employed officer.