Detailed information for colleagues
Craniomandibular Dysfunction (CMD) for Doctors
Dear colleagues, welcome to this continuing education course on craniomandibular dysfunction (CMD). CMD is an umbrella term that encompasses various pain and functional disorders of the masticatory system. This not only affects the temporomandibular joints, but also involves a complex interplay of muscles, joints, occlusion, and often psychosocial factors.
In the following, I would like to give you a detailed overview based on current guidelines and scientific findings and highlighting practical aspects for diagnosis and therapy.
Definition and classification
Definition
Craniomandibular dysfunction (CMD) is a multifactorial disease in which functional disorders occur in the jaw joints, the masticatory muscles, the occlusion (tooth contact), as well as in the jaw relationship and neuromuscular control.
In English-speaking countries, the term TMD (Temporomandibular Disorders) is most commonly used.
Epidemiology
In the general population, approximately 6–12% exhibit clinically relevant CMD/TMD symptoms.
The prevalence is generally higher in women than in men, especially between the ages of 20 and 40.
Some patients experience only mild or temporary symptoms; others may experience chronic disease with a significant impairment of quality of life.
Classification (according to DC/TMD)
The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) represent an internationally recognized classification for TMD. They divide TMD into two main groups:
- Pain in the masticatory muscles (myogenic disorders)
Myofascial pain with or without restriction of mandibular mobility
- Joint diseases (arthrogenic disorders)
Disc displacement (with repositioning, without repositioning), arthralgia, arthritis, osteoarthritis
Within these main groups, subtypes are defined to enable an exact diagnosis.
Anatomical and pathophysiological basics
Anatomical structures
Temporomandibular joint (temporomandibular joint): Consists of the condyle of the lower jaw (mandible) and the mandibular fossa in the temporal bone (temporal bone). Between them lies a disc of fibrocartilage that divides the joint and acts as a shock absorber.
Masticatory muscles: The most important muscles include the masseter, temporalis, laterally and medially pterygoid muscles.
Occlusion: The position of the teeth and the bite position (intercuspation) influence the position of the condyle in the temporomandibular joint and thus the joint load.
Biomechanics
The temporomandibular joint is a double joint (ginglymoarthrodial joint): it allows both rotational and translational movement of the condyle.
During normal function, the disc glides together with the condyle in the eminentia articularis.
Incorrect loading can lead to disc displacement, cartilage damage or arthritic changes.
Pathophysiology
The development of CMD is multifactorial. A common interaction of:
- Occlusal factors (malocclusion, high spots, missing teeth)
- Muscle tension (e.g. due to stress, nighttime teeth grinding/clenching = bruxism)
- Joint pathologies (disc displacement, arthritic changes, post-traumatic damage)
- Psychosocial factors (stress, anxiety disorders, depression, pain processing disorders)
- Systemic factors (rheumatism, fibromyalgia, hormonal influences, migraine)
Clinical symptoms
Jaw joint pain:
Localized preauricularly, can radiate to the temple, ear, neck, back of the head or rows of teeth.
Muscle pain:
- Painful tension, especially in the masseter and temporalis muscles.
- Trigger points in the masticatory muscles are often palpable.
Jaw joint noises (cracking, grinding):
- Occurs when opening or closing the mouth.
- Indication of disc displacement or structural changes in the joint.
Restricted mouth opening / jaw locking (trismus):
With or without pain
Headaches, facial and neck pain
- Tension or migraine-like headaches are not uncommon.
- Tinnitus, dizziness or ear pain can occur as accompanying symptoms (via trigeminal and otological connections).
Occlusal problems:
Subjective feeling that the teeth “no longer fit together properly”.
Differential diagnostic differentiation
Differential diagnostic differentiation
Since CMD overlaps with other medical disciplines, a thorough differential diagnosis is crucial:
Dental:
Pulpitis, periodontitis, orthodontic malocclusions.
Ear, nose and throat area:
Otitis media, tinnitus of other origins, tonsillitis, salivary gland diseases
Neurological:
Trigeminal neuralgia, migraine, cluster headache.
Orthopedic:
Cervical syndrome, intervertebral disc problems (cervical spine), shoulder joint disorders
Rheumatological:
Rheumatoide Arthritis, Polymyalgia rheumatica, Fibromyalgie.
Diagnostic
medical history
Detailed assessment of pain characteristics (location, intensity, duration, radiation, influencing factors).
Inquiries about bruxism (grinding or clenching), stressors, psychosocial stress.
Pre-existing medical conditions, previous dental or orthodontic treatments.
Clinical functional examination
Inspection: temporomandibular joint region, mouth opening, facial asymmetries.
Palpation: temporomandibular joint (preauricular), masticatory muscles (masseter muscle, temporal muscle, pterygoid muscle).
Temporomandibular joint sounds (auscultation/palpation when opening the mouth).
Mouth opening: dimension (in mm), lateral deviations.
Occlusion analysis: bite registration, positional relationships.
Instrumental functional diagnostics
Imaging techniques:
- Orthopantomogram (OPT): for an overview of teeth, jaw bones, and jaw joints.
- MRI: Assessment of the disc and soft tissue structures (disc displacement, inflammatory changes).
- DVT (digital volume tomography): three-dimensional representation of bony structures.
Instrumental procedures:
- Electronic recording of mandibular movement (Cadiax®, ARCUS®-Digma, etc.).
- Surface EMG to measure the activity of the masticatory muscles.
Psychometric Tests
If psychosocial involvement (stress, depression, anxiety disorders) is suspected, standardized questionnaires (e.g. Depression Questionnaire, Graded Chronic Pain Scale) can be used.
Therapy approaches
The treatment of CMD is interdisciplinary and should be tailored to the individual patient's etiology and symptoms. A combined therapy consisting of several modules is often used.
Reversible dental procedures
Bite splints
- Occlusion splints (Michigan splint, relaxation splint) are worn mainly at night.
- Goal: Relief of joints and chewing muscles, reduction of parafunctions (grinding/pressing).
Occlusal adjustment
- Minimal grinding of protruding fillings or crowns if incorrect loading has been objectively proven.
- Always proceed very carefully and conservatively.
Orthodontic treatments
- In cases of significant bite and jaw misalignments, orthodontic treatment may be useful.
- Principle: First carry out reversible measures (splint therapy) before implementing definitive changes.
Physiotherapeutic & manual medical therapy
Manual therapy
- Joint mobilizations, tractions, soft tissue techniques.
- Mobilization of the cervical spine, thoracic spine and jaw joints in interaction.
Physiotherapy
- Strengthening and stretching exercises for the masticatory muscles.
- Posture and coordination training (especially head and shoulder area).
Exercises for self-mobilization
- Patients receive instructions for relaxation and stretching exercises (e.g. controlled mouth opening exercises).
Psychosocial and behavioral medicine approaches
Stress management
- Coaching, cognitive behavioral therapy, relaxation techniques (PMR, autogenic training, biofeedback).
Sleep hygiene
- In cases of bruxism, improving sleep hygiene and sleep-promoting measures can be helpful.
psychotherapy
In cases of persistent pain or chronic courses with psychological comorbidity, psychotherapeutic support is important.
Drug therapy
Analgesics
NSAIDs (e.g. ibuprofen, naproxen) or paracetamol for acute pain.
In case of chronic pain, differentiated use (coanalgesics if necessary).
Muscle relaxant
In certain cases, for a short time (e.g. tetrazepam in countries where it is still approved, baclofen or tizanidine), but only for a limited time due to side effects.
Botulinum toxin injections
In cases of therapy-refractory myofascial pain and severe bruxism, injections into the masticatory muscles can be discussed (off-label use).
Interventional procedures
Intra-articular injections (corticosteroids, hyaluronic acid)
- In case of active arthritic processes or osteoarthritis symptoms.
Arthrocentesis / Arthroscopy
Minimally invasive procedures for lavage of the temporomandibular joint or for surgical intervention when conservative measures fail.
Prognosis and course
Most patients benefit from conservative therapies, especially splint therapy and physiotherapy, combined with stress management
Early diagnosis and treatment improve the prognosis and reduce the risk of chronicity.
Chronic cases often require consistent, interdisciplinary management.
Relapses can occur, especially if psychosocial stress recurs or if continuous care is not provided.
Interdisciplinary collaboration
CMD patients often require a team from different disciplines to ensure holistic and sustainable care:
Dentists / orthodontists (functional diagnostics, splints, occlusion correction)
Physiotherapists / Osteopaths (manual therapy, posture training)
Orthopaedists (cervical/thoracic spine findings, scoliosis, leg length discrepancies, etc.)
ENT doctors (differential diagnosis of ear problems, tinnitus)
Neurologists / pain therapists (chronic pain, headache, trigeminal neuralgia)
Psychologists / psychotherapists (pain management, stress reduction, behavior modification)
Practical tips for medical practice
Early diagnosis of craniomandibular complaints or non-specific head/neck pain that could indicate CMD.
Holistic approach: Also ask about and examine orthopedic and psychosocial factors.
High level of patient education: Explain that stress and parafunctions (grinding, clenching) have a significant influence.
Splint vs. grinding: First, reversible measures (splint), then, if necessary, grinding or denture/orthodontic interventions.
Pain management: Multimodal concepts for chronic conditions.
Conclusion and outlook
Craniomandibular dysfunction (CMD) is a multifaceted condition that affects more than just the dental world. Thanks to modern diagnostic procedures (DC/TMD), clear guidelines, and increasing interdisciplinary networking, we can now treat patients much more specifically. It is crucial to recognize the multifactorial etiology and tailor treatment plans to the individual.
With a combination of reversible dental measures (e.g. splint therapy), physiotherapeutic and psychosocial methods, it is in most cases possible to sustainably reduce or even eliminate pain and functional disorders.
Literature and source recommendations
Literature and source recommendations
Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), Dworkin & LeResche, J Craniomandib Disord (first published), currently being developed by the RDC/TMD working group.
DGPro (German Society for Prosthetic Dentistry and Biomaterials): Guidelines for dental functional diagnostics and therapy.
Bumann A., Lotzmann U.: Functional diagnostics and therapy of temporomandibular joint disorders. Quintessenz-Verlag.
Türp JC, Schindler HJ (eds.): Dental Functional Diagnostics and Therapy: Fundamentals, Diagnostics, Therapy Planning. Thieme-Verlag
Okeson J.:
Management of Temporomandibular Disorders and Occlusion. Mosby.
Thank you for your attention and I look forward to questions and subsequent discussion.
Would you like to become part of our broad practice network?
We look forward to hearing from you and developing innovative concepts together!
Use our specialist information to expand your CMD expertise and benefit from our interdisciplinary approaches. Together, we will create a solid foundation for optimal care for your patients.
