Some medicines, tricyclic antidepressants and antimalarials can also cause darkening of your gums The nastiest is the effect of acute necrotising periodontitis (sometimes known as trench mouth) which is advanced gum disease and the black colour is the result of dead tissue
The cost of replacing an airbag outright can be several hundred dollars, although it once again depends partially upon the exact make and model of the car that you're working with. Expect to pay on the order of $1000 to $1500 per airbag to be replaced. Number 3 -- Airbag Resetting. If you've been in an accident, and the airbags themselves have become deployed, you'll have to set them back up in order to be able to drive again.
Most states require that central air conditioning units be installed by licensed contractors, meaning the cost to replace your unit may include installation and labor fees. If installation and labor fees are included in the price, expect to pay anywhere from $2,650 to $15,600 for installation of a central air conditioning system as of 2013.