Occlusal Wear: Why Do My Jaws Hurt So Much?

What do you think the expected life span of a human being was 100 years ago?  Forty-three.  Life is so much more complicated today!  Are we living longer than our teeth were design to last?  Do people have more stress in their lives than way back then?  These are a few of the complicating factors I will attempt to explain in answering the question, “Why do my jaws hurt so much?”

History

Humans have been grinding their teeth since before we knew how to write.  Ancient fossil records show relatively young people had already ground their teeth flat.  This is attributed to their diet of unprocessed food, but shows that grinding is nothing new.  With the introduction of sugars into our diet we have seen a marked increase in cavities.  With cavities comes extractions or at least letting the tooth rot out of the head.  Loss of a tooth can significantly impact how a person bites their teeth together.

Causes of Grinding Teeth:

Malocclusion-

• Naturally occurring misaligning of the teeth happens.  Teeth come in rotated, tipped, and are sometimes just missing. This can cause crossbites,  overbites and underbites.  Why do you think we have so many orthodontists?
• Loss of a tooth/teeth.  When teeth erupt into the mouth they are pushed into the familiar arch shape by the actions of the lips and tongue.  Once into this arch form they remain fairly stable for the rest of your life.  This is until you loose one of your teeth in the archway.  The Romans knew how strong an arch can be when they designed bridges, buildings and aqueducts.  Individual teeth “lean” onto the one in front of it for their support.  If one is lost the teeth behind the one lost begin to drift forward.  This can significantly impact the way that you bite your teeth together.
• Trauma such as a broken jaw or tooth/teeth can impact the way that you bite.
• Iatrogenic Dentistry.  This is improperly placed restorations that can sometimes be placed inside your mouth by the dentist or his staff.  Just think about it.  You go to the dentist and need a crown.  He/she gets you so numb you don’t know whose mouth they are working on.  They prepare your tooth and make an impression by having you bite your teeth together.  From that mold they make a crown and cement it into your mouth.  Most people can tolerate a little mistake in their bites and don’t really notice that high spot when they slide their teeth sideways. After all if you think about it, most dentists only check your bite by clicking your teeth up and down.  So now your bite is off just a little from the crown and a little from the natural formation of your teeth.  You then have to have a filling done, then a bridge, then another crown.  At some point all of these discrepancies build up and you begin to grind your teeth to try and settle them into a more comfortable bite.
• Orthodontics.  They may look pretty, but do they bite right?
• Tempromandibular Joint.  Which came first: The malocclusion or the tempromandibular joint disfunction?  Both answers can be correct under the right circumstance.  A significant malocclusion can start the joint clicking and popping, and a worn down joint can cause malocclusion.

Central Nervous System-

This is not a very common condition but does afflict some unfortunate individuals.  It is usually diagnosed after all other causes have been “eliminated.”  It is where the brain has a condition that makes the muscle of mastication not function properly.

Occlusal Interferences-

Wouldn’t it be great if you could straighten out your teeth by grinding and clenching them into a good bite!  Well that is exactly what your body thinks it can do.  If it finds a high spot, it will usually try to wear it down or avoid it all together.

• Destroyers. These are want I call people who grind out their interferences.  You can look into their mouths and see teeth worn right off, cracked or broken.   They destroy crown, fillings, bridges, partial dentures and implants, too.  This in some cases can even contribute to periodontal disease and the death of the tooth’s nerve.
• Avoiders. Someone with a premature interference in their mouth somewhere, but it is too painful or disruptive to chew on so they shift their bite to some where else.  The most common other place is the front teeth.  Ever seen someone with flat front teeth? Avoider!
• Avoider/Destroyer. Occasionally someone will have both these conditions in their mouth.  In this case both the front and back teeth are worn down.

Examination:

This is where things begin to get interesting.  Ask 100 chefs how to cook lasagna and you will get 100 different recipes.  I have been going to TMJ continuing education course and workshops for over 25 years and have never heard the same treatment plan twice.  The most complete series of courses I had the privileged of attending was with Dr. Henry Gremillion’s at the University of Florida’s Parker Mayhem Craniofacial Pain Center.  Unfortunately, Dr. Gremillion is now the Dean of LSU School of Dentistry and the UF center has been closed due to budget constraints.

So, with all of the various treatment plans out there waiting to pounce on my back, I will attempt to carry you through how we treat our patients at Cape Dental Care.

History

• Complete health history is a must.  Medications, history of trauma, history of previous treatments preformed for this condition,and surgeries, just to name a few.
• Race: Strangely enough, Afro-American decent have less TMJ problems than other races.
• Past History of Oral Surgery consult and/or treatment
• Past History of any splint therapy
• Parafunstional habits: Nail biting, chewing ice, eating hard candy/foods, history of bruxing (grinding at sleep), clenching (grinding while awake) and/or heavy gum chewing.  You know cows are made to chew all day, not human beings.
• History of smoke/chewing tobacco or excess drinking of alcohol
• Does it bother them only during their menstrual cycle?  This maybe one of those central nervous system problems I alluded to, or not.
• Chronic headaches?
• Difficulty sleeping or history of snoring
• History of any trauma to the head and neck
• History of extensive tooth restorations

Physical Examination

• Clicking and/or popping of the joints
• Ligamentitis. Discomfort when the joint is pressed from the outside.
• Capsularitis. Discomfort when the joint is pressed from inside the ear canal.
• Medial pterygoid muscles
• Temporalis Muscles
• Masseter muscles
• Sternocleidomastoid muscles
• Digastric muscles
• Back of the neck muscles
• If the jaw joint translates.  The TMJ is really the only “double joint” in the entire body.  It has two main function: rotation and translation.  Translation is where the joint actually slides down the base of the skull to open the mouth as wide as it can.
• Eminence click.  When the jaw translates it usually stops before it runs out of skull to slide upon.  But with very flexible people (mainly women) they can slide too far and pop their jaw over the end of the translation zone and make a click.  This is also the spot where an open lock occurs.  An open lock is when you open your mouth too wide and it gets stuck open!  If this ever happens DO NOT PANIC!  Forcing it closed can cause a life time of damage to the tender apparatus of the TMJ.  Call a dentist immediately and/or try to move your jaw side to side.  The dentist will manually pull your jaw down and forward to unlock it. Remember do not force it close! Avoid open locks by not yawning very wide, don’t eat large piece of food (subway) and don’t sing to loud!
• Maximum mouth opening without pain.
• Deviation of the mandible right and left during opening
• Midline deviation of the mandible at rest
• Overbite/overjet.  This is how much you teeth overlap when closed.
• Sometimes I will take diagnostic models of the teeth to see if there is some other factors I may have missed. This involves making and impression of the teeth and getting a very accurate bite with a facebow.  A facebow  is simply an apparatus to record how your mandible relates to your maxilla and help in mounting the models onto an articulating chewing machine.
• Crossbites.  These happen when the upper teeth are inside the lower teeth when biting. Normally, the upper teeth are outside the lowers when biting.
• Angles Classification.  This is broken down into Class 1 (normal), Class 2 (overbite), and Class 3 (underbite).  This may involve only the teeth or it may indicate a skeletal problem between the mandible and maxilla.  I find less TMJ problems with the Class 3 patient and is probably due to the restricted biting platform.
• Periodontal status.  If there is gum disease the teeth may not be stable.  This may cause the teeth to move around and may make it harder to figure out where they bite.
• Soft tissue.  There maybe swelling or redness indication an infection, pathology or malignancy.
• Frankfort Mandibular Plane Angle.  This is an imaginary angle created between drawing a line from under the eyeball to the ear hole and from the lower border of the mandible.  It is used to see just how much the teeth are “leaning” onto each other in the arches.

Joint Vibration Analysis

This is a very sensitive microphone placed over the joints like small headphones.  It picks up the sound frequencies that come from the joints when they open and close.  This is not used to diagnose TMJ problems, it is just a tool to help the doctor figure out what is wrong.  It uses a computer to analyze the different frequencies and is a good tool to use before any major work is done to your mouth.  It is a physical record of the status of your joints and can be used in the court of law.  Everyone wishes they had had one of these before they had their car accident to show just how badly they were damaged during the accident.

We mainly use it to rule out any TMJ problems or to show that our treatments have not change the TMJ for the worse. Fortunately, over 80 percent of what people call a TMJ problem (including medical doctors) is not TMJ oriented, but instead myofacial pain (or pain from over worked muscle).  What is the main cause of myofacial pain?  Malocclusion.

NOTE: We do have a CBCT (cone beam CT) scanner and a panograph in the office, but I feel having a picture of it is over kill and too much radiation to subject my patients to just to know there is something wrong in the joints.  If I can hear something wrong, then there is something wrong.  MRI’s are much better for seeing the joint than CAT scans (and without any radiation).

TekScan

Wow!  What a great tool.  Everything in dentistry can be boiled down into having a good bite.  The ways we are taught to check the bite in dental school is in a word, “inadequate.”  They teach the simplest way by using bite paper alone.  Oh, they say they are “manipulating” the jaw into the right positions to see if the bite is correct, but that is about it.  Big dots or little dots. Why does it matter?  I have seen some dentists put the bite paper into the mouth, see a large spot and then attack it like a shark!  If they would have used the TekScan they may have seen that that big spot that attracted their eye wasn’t the spot to adjust.  Instead, it was that tiny little speck next to it that was the problem.  Still others I have seen ask the patient where they feel their teeth touching first and then spend the next hour chasing spots around the mouth. It isn’t until the patient gets tired of getting their teeth ground down and the dentist gets worried about all the teeth they have altered that it ends.  Then after that the patient dares not to bring the subject up and the dentist doesn’t bring it up for fear they will have to go at it again.

TekScan was developed for dentistry back in the 1980’s.  Now it has expanded into many other manufacturing techniques like tire fabrication, robotics, and space flight.  Dr. Scholl’s has it in their foot diagnostic centers in the malls.  But in dentistry it has not taken off.  One really good reason is the cost.  Another reason it is not widely used is it is complicated.  Believe it or not, there are dentists in this country who do not even have computers in their office!

The TekScan is a pressure sensitive sensor that makes a movie of how your teeth come together.  I put it on a TV monitor right over the patient’s head when we use it.  Once you see it work a few time, the patient can see the results themselves.  When you show the patient that they are biting on their right side 75% more than their left, they get it.  If you just used bite paper you would never know that.  Sure you would have dots the same as what we get at the end of the movie, but you would not see what the movie was really about.  It would be like reading the last sentence of a great novel before you read the book!  You would have an idea how it ended, but not how you got there.

Treatment:

NTI

Nociceptive trigeminal inhibitor.  Cool name?  Not really.  Cool devise?  Yes, really!  If this was all the treatment your dentist did for you when you showed up at their office with extreme myofacial pain, then God bless them!  Is it good long term treatment? NO!

Several blogs could be written about the NTI, but here I am going to attempt to explain it in simpler terms.  We use the NTI in our practice as a simple diagnostic tool, only.  If it works preventing your pain, then it is most likely your bite causing your pain (when the JVA is negative, of course).  It takes me about 15-20 minutes to manufacture a NTI for your mouth and you should wear it as much as possible for the first week.  In most cases, it will reduce or completely eliminate the myofacial pain.

The NTI is a small piece of plastic that snaps onto your front teeth only.  You can take it in and out.  I like to use it on the upper teeth when I can, it makes people look like Jerry Lewis in the Nutty Professor.

The way it works is complicated and has to do with the nerves of  your front teeth.  The front teeth are wire to the spine in a biofeedback loop.  When they touch together they cause the muscle of mastication to loosen up and relax.  This is thought to be so the front teeth will not become damaged while eating hard foods.  We can then exploit this biofeedback loop to our advantage. If relaxing the chewing muscle helps the pain go away, then bingo!

This is written in the chart and explained to every patient who receives a NTI:

Informed Consent, Reviewed health history, THIS APPLIANCE IS ONLY INTENDED FOR USE WITH ACUTE MYOFAICAL PAIN EPISODES. CHRONIC USE CAN CAUSE POSTERIOR TOOTH ERUPTION WHICH COULD WORSEN SYMPTOMS AND CAUSE MALOCCLUSION.

Nociceptive Trigeminal Inhibitor manufactured with acrylic over the maxillary/mandibular central incisors. Trimmed and polished.  Patient counseled on how to and when to wear.  OHI (wash appliance with soap and water and/or toothpaste and keep in box when not in use).

Wear the appliance when sleeping and daily during the most stressful times.  Never wear while eating. Discontinue all chewing gum. This is NOT an orthodontic device and should not be worn 24/7.  It REQUIRES the teeth come together each day for at least 8 hours to keep the teeth in proper position. Neuromuscular parafuntional habits may not resolve immediately and can be aggressive in maintaining itself. If it becomes uncomfortable, too tight or loose, or irritating in any way, the patient has been instructed to contact the office immediately for a follow-up visit.  Risks, benefits and alternative discussed.

Dogs love to eat NTI. If lost, the patient understands a new one can be made for another full fee.

Next Visit: Re-evaluation of myofacial pain

The TekScan Series of Appointments

If myofacial pain syndrome is diagnosed, then the patient is offered two modalities of treatment.  This first is a hard night guard.  It is a 50 cent piece of plastic that we manufacture and delivery to you to wear in your mouth at night for the rest of your life.  We of course charge more than 50 cents, but the idea is it is for LIFE.  This plastic hard (NOT SOFT) night guard is then adjusted with the TekScan to simulate the proper occlusion in your mouth.  We can grind on this all day without altering your teeth in the slightest.  This is a very popular way to treat both myofacial pain and TMJ problems.  The fact that it is in good occlusion helps the myofacial pain and the thickness of the appliance helps the TMJ.

The other way to treat myofacial pain is through what I call the TekScan series of appointments.  This is a complete equilibration of your teeth.  I was very please to hear from one of my old associates the other day when he said he went to a continuing education course on TMJ dysfunction and Myofacial pain and they said dentistry was getting away from complete equilibrations.  No doubt it was because too many dentists were getting in trouble grinding the heck out of peoples teeth.  It didn’t surprise me, because if they were doing it the way they learned in dental school, they could screw up a lot of mouths if excessively applied.

The TekScan series of appointment is separated into 3 or more appointments, the first one is 2 hours long!  Yes, and we use every bit of that time.

TekScan 1

• Line up the dots- We as dentists have learned where and where you should not bite your teeth together.  Lining up the dots is done in maximum intercuspation or how your teeth come together naturally.  The features that interest me are biting more on one side than the other; slides in the bite, and hitting the wrong parts of the teeth.
• Right and left lateral excursions- This is when you slide your teeth sideways onto your canines.  I look for working and non-working side interferences and guidance.  That is when you put food on one side of your mouth to chew you should only touch on that side and not the other.  This is a major cause of myofacial pain is is essential to a successful equilibration.
• Protrusive excursion- This is when you grind your teeth forward onto only your front teeth.  Normally all the back teeth should not touch when you move you jaw forward.  This is the most forgotten and hardest to detect part of a complete equilibration.

TekScan 2

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