Parents are held liable for accidents caused by their minors in Pennsylvania. The parent is held responsible via vicarious liability which extends the responsibility and fault for wrecking the car from the unlicensed driver to the parent or owner of the vehicle. Vicarious liability takes many forms and is not limited to only parent-child relationships. Usually it tends to hold the "master" responsible for the acts of their "servants" provided that at the time of the act, the servant was discharging their duty.
In this case the vicarious liability is specific on parental liability and this is provided for under a Pennsylvania Statute. This is the 23 Pa. Cons. Stat. § 5502, which states that "the parent of a child found liable or is found to be guilty by a competent court that has jurisdiction of the tortious act will assume liability of the injuries suffered by the victim as set by law". The parent is held liable and is supposed to pay $1,000 if the injuries are to a person or $2,500 in case it was an accident as per 23 Pa. Cons. Stat. § 5505. Therefore in the case that your unlicensed teen happens to wreck your car, you will be fully liable for it.
In addition to the above, as the parent you will still be held liable for permitting or authorizing an unlicensed person to drive a vehicle you own or one that is under your control. You will be held liable as this is in contravention to a legal statute, 75 Pa. Cons. Stat. § 1574, which prohibits any person from allowing an unlicensed person to drive a motor vehicle they own or one that is under their care. Parents are by virtue of this section strictly prohibited from allowing their unlicensed teens to drive their cars and if they do, they will assume liability.