Can a car accident cause TMJ?

Yes, it is possible for a car accident to cause ongoing pain and dysfunction in the
temporomandibular joint. Traumatic injuries to the craniofacial region are among the leading
causes of TMJ in patients. In addition to other bodily injuries, victims of a car accident may experience whiplash. Whiplash is a neck injury resulting from a rapid forward or backward
movement of the neck, and patients may experience varying degrees of severity. Rapid
movement of the neck in a backward direction is referred to as hyperextension while rapid
movement of the neck in a forward direction is referred to as hyperflexion. In a rear-end vehicle
collision, whiplash typically involves hyperextension followed by hyperflexion, resulting in an
injury to the jaw. The onset of TMJ resulting from whiplash or brain tissue injury may result in
severe head and facial pain requiring the care of a specialist.

The process of whiplash may be visualized using Newton’s Laws of Motion. Depending
on the angle of the collision, a victim may experience both linear as well as rotational
acceleration. Newton’s First Law stipulates that an object at rest tends to stay at rest while an
object in motion tends to stay in motion unless subjected to an external force (gravity, friction,
etc.), and a driver or passenger seated in a moving vehicle would be subjected to such an external
force upon collision. Newton’s Second Law (force = mass * acceleration) may quantify the
impact of trauma resulting from the force of the collision, while Newton’s Third Law stipulates
that for the action (collision), there will be an equal and opposite reaction which could include
trauma inflicted upon the victim of the collision. Immediately following the collision, the head
tends to stay at rest momentarily while being subjected to a force pushing the body forward,
followed by forward motion. A passenger restrained by a seatbelt would subsequently be pushed
backwards, and the time gap between the initial force and the bodily response based on the laws
of physics may lead to traumatic neck injuries. Headrests should be positioned as close to the
head as possible to minimize the impact of hyperflexion following hyperextension. Prior to the
widespread adoption of the automobile, train accidents were a significant cause of whiplash.
While auto-related accidents are the most common cause of whiplash in the present-day, it is important to note that whiplash may also be caused by bungee jumping, sports injury, physical
abuse, or by banging one’s head in a rapid manner.

Modern vehicles are now equipped with more technology that may mitigate the severity
of injuries resulting from car accidents. Since the National Traffic and Motor Vehicle Safety Act
was passed by the United States Congress in 1966, all new vehicles are required to have seatbelts
for each passenger. Since the Intermodal Surface Transportation Efficiency Act of 1991 fully
went into effect in 1998, all new cars and light trucks are also required to have airbags on both
the driver and passenger side. Both seatbelts and airbags in new vehicles have helped to reduce
the likelihood of death or severe injury resulting from car accidents, as well as reduce the
severity of whiplash injuries. Following a rear-end collision (or even application of the brakes),
seatbelts may lock in position and restrain the passenger from rapidly moving forward based on
Newton’s First Law.

All modern vehicles manufactured after 1998 have sensors to detect collisions, and more
sophisticated modern vehicles may alert the driver in advance or even intervene and brake
automatically if a collision is anticipated. These vehicle-specific systems are developed after a
great deal of modeling and testing by engineers. Once a severe collision is detected by the
pressure and crash sensors, a signal is sent to the inflator unit within the airbag control unit to
trigger the chemical reaction needed for airbag deployment. If a passenger is thrust forward
rapidly following a collision or rapid braking, the vehicle’s airbags may deploy based on how the
vehicle’s systems are programmed. Following deployment, airbags are engineered to inflate
rapidly following a collision and may inflate in as little as 40 milliseconds (less than 1/20 of a
second). The inflation of an airbag is typically the result of a chemical reaction combining azide

(NaN3) and potassium nitrate (KNO3) to produce nitrogen oxide. Following deployment, a
vehicle airbag will quickly deflate.
Despite continuous advances in vehicle technology and the likelihood of a future with
semi-autonomous or even fully autonomous (driverless) cars, it is important for motorists to
remain vigilant of all possible risks while driving. It is advisable to select a vehicle that has been
tested for safety and happens to satisfy Federal standards for seatbelts, airbags, and well-
positioned headrests. Motorists and passengers should always ensure that they wear their
seatbelts while the vehicle is in motion at any rate of speed and position their headrests to be as
close as possible to the head to minimize the severity of whiplash injuries in the event of a

New Jersey law requires all motorists to carry a minimum level of liability insurance
before operating a motor vehicle. Auto insurance companies are also required to compensate
victims of a car accident to cover the cost of evaluation and treatment for a wide range of
physical injuries under personal injury protection (PIP) coverage. If you have experienced the
onset of TMJ symptoms following a motor vehicle accident, please contact our office to undergo
a comprehensive exam and diagnostic imaging at Dr. Federman’s office. If Dr. Federman
believes that your symptoms are directly the result of a traumatic injury resulting from a motor
vehicle accident, we will work with a leading injury attorney in your geographic area to file a
case on your behalf and obtain adequate compensation from the responsible party’s auto
insurance company.