TMJ Pearls, DTR, and Neural Occlusion
Advancing Dental Medicine with “4-D DENTAL MEDICINE”
By: Dr. Nick Yiannios
The fourth dimension in the field of physics is often referred to as space-time. I propose that in the field of dental medicine, like similarities occur in the masticatory system which are typically, totally ignored, and which may have profound physiological, biochemical, biomechanical, and neurological influences upon the health of a given patient in ways that are inconceivable to most health care practitioners. The intricacies and interrelationships of the shapes and position of teeth, the bony components of the TMJ’s and their cartilaginous disks, in SPACE and TIME, can effect profound neurophysiologic change (in this context, resulting in painful muscles of mastication) under certain conditions. An objective measurement of these events is now possible via precise digital technologies, allowing an adept practitioner the ability to practice advanced and effective TMD treatment in a manner inconsistent with traditional thinking. The following briefly outlines Dr. Nick’s rapid and unconventional approach to TMD screening and therapy, which usually does not involve splints, medications, lasers, surgery or physical therapy, but instead a respect for, and precise manipulation of, the totally ignored 4th dimension in dental medicine, SPACE-TIME… Because:
The only joint in the human body with a hard tissue stop (the teeth), is the TMJ (temporomandibular joint). TMJ = temporomandibular joint-‐an anatomical joint. We each have a right and left TMJ, two joints in total, located just in front of our ears. The TMJ consists of the top of the mandibular condylar bony head + the cartilaginous disk (or capsule) which normally sits on top of the condylar head, separating and protecting the condylar head from the underside of the temporal skull bone, in an indentation within the underside of the skull known as the glenoid fossa:
TMD = temporomandibular dysfunction-‐a catchall phrase to encompass various maladies that involve the human jaws, the human jaw joint, and the various structures involved (including muscles, cartilage, ligaments, bone, nerves, and teeth). A disorder that often presents with neurological, orthopedic, and/or biochemical consequences. Painful and/or damaged TMJ’s may arise from:
- Microtrauma (bite issues which can lead to muscular and eventually cartilage and bony issues); Disclusion Time Reduction (DTR) can readily can address the microtrauma problem, in a patient who possess two stable and adapted TMJ’s. Microtrauma will maximally damage the lateral pole of the TMJ disk
- Macrotrauma (physical damage to one or both TMJ’s from accidents, sports injuries, etc); DTR is only useful in this circumstance if the TMJ’s have become stable and adapted, and muscle spasm from an additional compounding issue, an improper bite, is the primary genesis of the patients pain. Macrotrauma can readily damage not only the lateral pole of the TM disk, but the medial pole as well. Damaging the medial pole is more problematic than just damaging the lateral pole.
- Systemic (whole body) issues involving cartilage, muscle and/or bone, particularly the upper cervical vertebrae and associated structures
- Imbalanced sympathetic nervous system influences
There are ways to screen a patients situation via physical exam (the way the upper and lower teeth and jaws relate to one another) which may be used to ascertain if the TMD problem is likely due to a discrepancy in the way the bite and/or the muscles interact, resulting in a solely muscular TMD issue, vs. if the TMD problem is resultant of what is known as a Foundational Occlusion issue (the way the temporomandibular joints themselves are properly arranged, or not, with resultant changes in the bite), resulting in a situation which involves not only a muscular TMD issue, but an orthopedic one as well. The principles of Foundational Occlusion are proffered by the world renowned Oral and Maxillofacial TMJ surgeon, Dr. Mark Piper of St. Petersburg, Florida. Dr. Nick has been personally trained by Dr. Piper and has integrated many of the Foundational Occlusion concepts into his Neural Occlusion screening protocol. Issues that are solely due to a muscular TMD resultant of a bite discrepancy, typically respond very favorably to a digitally-directed bite alignment procedure known as Disclusion Time Reduction (DTR) therapy, while issues that are due primarily from an orthopedic issue, respond less favorably to the occlusal/bite adjustment known as DTR. Fortunately, a large percentage of TMD pain is resultant of the former, and is typically predictably treatable via DTR therapy. Muscular TMD issues resultant from primarily a bite issue typically involve either the lateral pole of the TMJ cartilaginous disk, ill-fitting dental work, or improperly related teeth after orthodontic or surgical therapies. More serious TMD issues are typically resultant of damage to the medial pole of the TMJ cartilaginous disk. Orthopedic/medial pole issues do not respond as predictably to DTR therapy. The key is to ascertaining which general type of issue the patient presents with, via objective diagnostic gathering to arrive at a proper diagnosis or diagnoses. Fortunately, most muscular TMD issues are due to a misaligned bite, and are by far the predominant cause of TMD pain. An orthopedic or systemic issue may require further investigation involving modalities such as MRI imaging, laboratory blood testing, or even surgery.
The bite can usually be manipulated to calm hyperactive chewing muscles (which can readily cause pain) via DTR therapy, in patients with a muscular TMD issue due to a misaligned bite. A world-renowned lecturer and researcher, Dr. Robert Kerstein of Tufts University, introduced the principles of DTR therapy to dental medicine in the late 1980’s. Dozens of evidence-based and peer-reviewed publications exist on this topic buried in the scientific literature, but most all practitioners of dental medicine have never even heard of the concept, let alone understand how to apply it. Dr. Nick was personally trained by Dr. Kerstein relative to DTR therapy many years ago, and has practiced using this novel approach (coupled with a unique protocol Dr. Nick himself has devised) to occlusal/bite therapy on a daily basis ever since. CRITICAL POINT: the bite and TM Joint stability are intricately connected to one another. Affecting the TMJ’s can readily affect the bite, and vice versa! Neural Occlusion refers to a series of objective protocols whereby Dr. Yiannios uses both physical exam and objective measurement technologies (including MRI and CBCT imaging/not just the traditional subjective patient history and exam metrics) to arrive at a TMD diagnosis(es) that will either confirm or eliminate the usefulness of DTR as being a useful treatment modality for a given patient. The technologies utilized for this purpose are CBCT (3D imaging/bone visualization/hard tissue imaging), MRI (3D imaging/cartilage and muscle/soft tissue imaging), Joint Vibration Analysis (JVA is a TMJ cartilage screening measurement tool, throughout the dynamic range of motion), EMG (muscle activity measurement technology), digital 2D x-rays (normal dental pathosis screening), and T-Scan (computerized force/time measurement technology). A novel occlusal parameter that Dr. Yiannios has coined and published about known as Frictional Dental Hypersensitivity (FDH) is also incorporated into the Neural Occlusion protocosl. In his experience, most all patients who display an elevated FDH response are muscular TMD sufferers, and he uses this observation coupled with history, exam, and a mixture of the above objective metrics to decide if an occlusal adjustment therapy is right for them, or if a totally different route needs to be undertaken. A large percentage of TMD pain is primarily due to hyperactive (overworked) muscles; a smaller percentage is due to intracapsular (cartilage/TMJ disk) or bony (arthritic/inflammatory) problems, with a small percentage relating to infectious or orthopedic problems such as Lyme’s disease, rheumatoid arthritis, osteoarthritis, and/or ligament laxity issues. Many TMD patients’ temporomandibular joints are damaged, while some are not, but often their muscles are primarily responsible for their pain. Some TM joints were damaged years ago, and have adapted quite well but the muscles moving across the joint are not at all happy. A very common example whereby a patient may experience muscular TM pain would be due to dental work or orthodontic work that caused muscle spasm since the bite was not keyed in within those patients’ physiologic tolerances (in relation to space and timing within that patients unique range of chewing motion). The key is to ascertaining whether or not the joints are stable and adapted enough to expect Disclusion Time Reduction therapy to aid this muscular TMD patient. If in fact that patients TM joints are damaged, as with any damaged joint in the human body, it is possible that over time the joint foundation itself may change and break down, with resultant alterations of the bite, which could negate the benefits of DTR, or any other type of bite therapy, hence the importance of screening the patients’ TMJ’s for normalcy or signs of adaptation and stability.
CRITICAL POINT: most TMD patients have muscular issues that manifest as pain! DTR (Disclusion Time Reduction) therapy effects profound and positive changes for a large percentage of TMD patients whose painful symptoms are found to be primarily muscular in origin, as long as the cartilaginous and bony components in the TM joints are perfectly normal, or, if abnormal, stable and adapted TM Joints. DTR utilizes an Occlusal (bite) Adjustment procedure known as Immediate Complete Anterior Guidance Development (ICAGD) that involves orthodontically moving, or alternatively, adding and/or removing minuscule and precise amounts of tooth structure in a timed and objective manner to enable the masticatory (chewing) muscles to work more efficiently than before DTR was implemented. DTR therapy does NOT involve splint therapy!
The fact that the bite is most certainly related to TMD pain problems becomes apparent when a practitioner uses precise and objective modalities to examine & adjust the bite (such as T-‐Scan® digital occlusal technology and Bio-EMG III electromyography (EMG) technologies), in a set of stable and adapted temporomandibular joints. Mainstream dentistry disbelieves the above statement… Most all dental practitioners solely use bite ribbon which has been shown in the scientific literature to have an accuracy of ~22% relative to the measurement of force per unit time…
There exist objective digital modalities (T-Scan®) that are far more accurate for the measurement of force & time (95% force reproduction accuracy, Koos, 2010). Almost all dentists use the old fashioned, imprecise & subjective bite ribbon to check the bite while performing dental work… What breaks teeth? MUSCLE, always!!
Scientific research since the early 1990’s has shown that it is possible to control & relax hyperactive chewing muscles through precisely and objectively decreasing the timing of the posterior excursive frictional engagements (rubbing between opposing teeth as we chew sideways) in the human bite: (Kerstein & Wright, 1991) (Kerstein 1992, 1993, 1994, 1995, 2001, 2004, 2010 ) (Chapman, Kerstein & Klein, 1997) (DuPont, Kerstein & Glenn, 2001) (Kerstein & Radke, 2006, 2012, 2013)
All one needs to do is precisely adjust the amount of force between opposing teeth over specified periods of time, to relax hyperactive muscles of mastication (in a patient with a pair stable and adapted TMJ’s)… The Central Nervous System (CNS) “likes” a fast & efficient bite, with little frictional rubbing between opposing posterior/back teeth. The CNS “dislikes” a slow & inefficient bite, laden with excessive frictional “rubbing” in the posterior/back. Slow down/make the rubbing back and forth as we chew less efficient, and hyperactive chewing muscles can readily result. Tekscan corp. out of Boston has a patented digital bite sensor known as the T‐Scan® which can measure the percentage of force between opposing teeth per unit time…
T-scan® digital technology allows Dr. Yiannios to track force & time in 3/1,000 second increments. Precise and miniscule changes to the human bite can result in more efficient muscular output. Through TIMING between the interactions of opposing teeth, one can control the masticatory (chewing) muscles in a patient with a pair of stable and adapted temporomandibular joints. Efficient muscles produce little to no LACTIC ACID… Inefficient muscles produce lots of LACTIC ACID per anaerobic (without oxygen) metabolic pathways. Overwork when you work out, and you are sore – due to the excessive lactic acid produced via anaerobic metabolism:
The same applies to chewing muscles…they are skeletal muscles just like your biceps or your triceps. Overwork your chewing muscles and they too will produce excessive amounts of lactic acid. Lactic acid is toxic to all mammals on the planet, including humans. Increase muscular efficiency per Tscan force/time metrics combined with muscular EMG readouts (tracking muscular output in the same 3/1000 second increments), and muscular TMJ/D pain symptoms typically resolve! There are objective ways to ascertain if muscle is likely the culprit (rather than cartilage and/or bone). There are ways to screen the cartilage and bone OBJECTIVELY in a private practice as well using 3D imaging technologies such a Cone Beam Computer Tomography (CBCT) or Magnetic Resonance Imaging (MRI):
JVA headset looking for damaged cartilage. The patient simply opens and closes and the sensors “listen” for damaged cartilage BONE:
This patient is relatively stable and adapted in the bony aspect of this right TMJ. Regardless, other steps (in the Neural Occlusion protocol) will need to be taken prior to deciding that this patient is a DTR candidate.
This patient will NOT undergo DTR due to the instability (flattened arthritic changes in condylar head and articular eminence, coupled with degenerated condylar bone marrow and apparent synovial cyst in the condylar head). Another imaging more accurate modality for screening cartilage that is available outside of our private practice: MRI-‐Magnetic Resonance Imaging-‐CARTILAGE in still position
MRI imaging of the soft tissue cartilagenous disks is often used in our practice to screen patients prior to implementation of DTR, or any other bite adjustment therapy. The patient is referred to an off-site imaging center the day of their DTR screening appointment (utilizing Dr. Nick’s Neural Occlusion screening protocol) to help ensure that their case will be amenable to DTR therapy. Possible signs/symptoms of TMD: sore chewing muscles/hypersensitive teeth/broken or excessively worn teeth/popping and clicking joints/sore TMJ’s/sticking ones tongue between ones teeth/clenching or grinding teeth/flattened out teeth/broken dental work/soreness in and around the ears/headaches in the temple region, beside or behind the eyes/sore & tired neck muscles (these are accessory muscles of mastication)/soreness in the shoulders can also be related/sharp pain in and around the ear for which the ENT doctor has no explanation, etc… Most practitioners interested in TMD in dental medicine worry solely about the TM joint itself, the bone and cartilage…forgetting about the supporting TM musculature, the teeth, the bite, & associated neurology. Fact: most of the time, bone and cartilage adapt and remodel-BUT, there are times when damaged joint and or cartilaginous capsules ARE the pain problem, not the muscles! The key is to determining when the muscles are the primary issue causing the pain, hence the utility of the Neural Occlusion protocols… Muscle is a certain length for a lifetime/doesn’t remodel. Most dentists only use bite splints to treat “TMJ”. “TMJ” is just anatomy, TMD is a broad classification of TMJ disease/a more appropriate descriptor. According to the National Institute of Health (NIH), more than 10 million Americans suffer from “TMJ” problems. More women than men seem to be afflicted (NIH). The NIH cautions against performing irreversible changes to the bite to treat TMJ problems. This stance was implemented after studies conducted in the 1960’s and 1970’s seemed to indicate that the bite rarely (remember bite ribbon as being approximately 22% accurate in regards to force/time?) has an effect on TMD symptomatology (back then they could only study with the very inaccurate bite ribbon).
This “hands off” statement is due to the modalities historically used to study the human bites relation to TMJ problems; traditional bite ribbons which are grossly inaccurate vs. an objective digital metric such as T‐Scan® which is very accurate.
In support of the NIH stance, it would be important to determine that a muscular issue exists resultant of the bite and that stable and adapted TMJ’s do indeed exist prior to initiating Occlusal (bite) Adjustment therapy (hence the importance of the Neural Occlusion protocols). Disclusion Time Reduction therapy (DTR) was first discovered by Dr. Robert Kerstein, formerly of Tufts University in Boston, Massachusetts. Dr. Nick Yiannios has implemented the Neural Occlusion protocols, which compliment DTR, by helping a practitioner more predictably address a given patients applicability for DTR therapy, or not… Quite simply, the Neural Occlusion protocols help Dr. Nick arrive at an objective differntial diagnosis (or diagnoses). DTR is implemented through an Occlusal (bite) adjustment procedure known as ICAGD (Immediate Complete Anterior Guidance Development). ICAGD is NOT equilibration which is the bite adjustment procedure typically used in dental medicine. It is very different both in its approach, and in its final outcome. These are two totally different types of Occlusal Adjustment procedures!
|Goal:||CR/CO coincident||timed/immediate post. Disclusion|
|Closure position:||guided/iatrogenic||unguided/natural closure|
|Ant. Guidance:||not measured||objectively measured (<0.41 sec)|
|Quantifiable endpts:||no||yes/objectively measured|
|Effect mastic muscl:||variable reports||decreases MM/TA statistically|
|PDL influence:||not considered||neuroanatomically critical|
Very few in dental medicine routinely practice DTR via ICAGD due to:
- Ignorance due to mainstream academia not realizing the usefulness of the procedure
- Bias to other methods (many of which lack abundant scientific evidence)
- An inability to implement protocols to distinguish between muscular TMD
- The inability to identify other TMD issues (Neural Occlusion helps with that)
The principles behind DTR can be used to control chewing muscles, in the right patient, by controlling precisely the timing and forces between opposing teeth. DTR involves precise, methodical, and minuscule changes by subtraction and addition to the bite (when orthodontic movements are not an option), IN A PATIENT WITH CONFIRMED STABLE & ADAPTED TMJ’S, which is confirmed with computerized data along the way…
What do we mean by stable & adapted joints? Critical Answer: the medial portion of the TMJ articular/cartilaginous disk sits atop the mandibular condylar head, separating the condylar head from the glenoid fossa-‐ MINIMALLY! Though DTR can be performed without confirmed stable & adapted joints, the outcomes are less predictable… Dr. Nick’s definition of a: Stable Occlusion (bite): “To allow the elevator muscles of mastication to take both mandibular condyles quickly and efficiently to a pair of stable and adapted temporomandibular joints, with the intracapsular structures stably interposed between the mandibular condylar heads and their respective glenoid fossas, free of odontogenic neurological interferences in space-time.” Dynamic Occlusion (moving/excursive bite): “To allow the excursive muscles of mastication to quickly, efficiently and harmoniously orchestrate their intended purpose in the presence of stable and adapted temporomandibular joints with the intracapsular structures stably interposed between both mandibular condylar heads and their respective glenoid fossas and articular eminences throughout the full range of motion, free of odontogenic neurological interferences in space-time.”