Parafunctional habits such as bruxism, nail biting, clenching, or gum chewing.

Life stressors.

Apertognathia and/or overjet greater than 6 mm.

Lack of posterior dentition leading to muscle hyperactivity.

Jaw pain with tenderness of the muscles of mastication and/or supramandibular and inframandibular muscles.

May see wear facets of the dentition.

Scalloping of the tongue.

Morsicatio buccarum, laborium, or linguarum.

Patients may complain of sore teeth.

Decreased range of motion.

Buccal exostoses (Wolff’s law states that bone responds to the pressure exerted on it by an osteoblastic response).

Patients often will complain of pain on the side of their face as opposed to pointing to the preauricular region. Pain is usually diffuse and involves the muscles of mastication (DDx of MPD-trigeminal neuralgia, atypical facial pain, fibromyalgia).

NSAIDS to reduce pain and inflammation (e.g., ibuprofen 600 mg QID × 2 weeks, naproxen 500 mg BID × 2 weeks, Mobic 7.5–15 mg daily for 2 weeks)

Occlusal appliances

Soft diet

Warm compresses

Occlusal equilibration

Trigger point injections

Botox intramuscular injections

Replacing the posterior dentition

Physical therapy

Due to an imbalance between catabolic and anabolic processes. This leads to expression of catabolic cytokines (TNF-alpha, IL-1, IL-6), initiating liberation of collagenases and proteases that result in degradation of the articular cartilage. Osteoarthritis of the TMJ can be preceded by internal derangement and trauma and can also develop in patients that have had orthognathic surgery.

Joint destruction due to an inflammatory arthritic process (e.g., rheumatoid arthritis (RA), juvenile rheumatoid arthritis, psoriatic arthritis, gout, pseudogout, ankylosing spondylitis, reactive arthritis).

Depends on the extent and the level of life disruption . May include medications, physical therapy, or steroids or disease-modifying drugs.

For mild cases failing conservative treatments, consider arthrocentesis and arthroscopic procedures.

More advanced cases may require arthroplasty or total joint replacement.

Trauma

Joint laxity

Parafunctional habits

Altered joint lubrication system

Anchored disk phenomenon (disk adhesion to articular fossa)

MPD

Look for decreased maximal incisal opening (MIO) , deviation, deflection, palpable clicks (reciprocal), and crepitus. Patients often will complain of pain in the preauricular region as opposed to pointing to the side of the face.

Diagnosis by MRI-T1 and T2. Disk is normally displaced in an anteromedial vector. Can see osseous changes and abnormal contours of the disk.

Disk displacement with reduction – patient opens the mouth with an accompanying click that is produced when the condyle passes over the posterior portion of the disk. During opening, the disk returns to its normal anatomical position in relation to the fossa and condylar head. During closing, a second click can be appreciated as the condyle passes back over the thickened posterior portion of the disk.

Disk displacement without reduction – patient attempts to open but the condyle cannot pass over the posterior band of the disk. May see deflection to the ipsilateral side and decreased excursion to the contralateral side. This results in limitation of opening.

Wilkes classification classifies the degree of internal derangement and provides guidance in relation to treatment options (Table 2.1).

Conservative treatment as previously mentioned (if appropriate).

Intra-articular injections with a local anesthetic/steroid mixture.

Those unresponsive would benefit from arthrocentesis with or without arthroscopy, arthroplasty with repositioning, or meniscectomy with or without graft/replacement, or modified condylotomy.

Postoperative management – physical therapy/range of motion exercises.

Muscle fibrosis secondary to radiation, myofascial pain, tumors, infection, hysteric trismus, myositis ossificans.

Fractures involving the condyle, zygomatic arch, or coronoid process.

Clinical exam – decreased MIO , inability to appreciate translation of the condylar head.

Orthopantogram – can see a radiodense mass, overall bony morphology, and coronoid hypertrophy.

CT with contrast – defines the extent of the heterotopic bone/ankylotic mass. It also delineates the relationship of the mass to vital structures (foramen ovale, foramen spinosum, carotid canal, jugular foramen , pterygoid plexus). CT also aids in fabrication of a custom TMJ prosthesis in the setting of immediate reconstruction.

Aggressive resection of the fibrous and/or bony ankylotic mass.

Coronoidectomy on the affected side and measure MIO intraoperatively.

Coronoidectomy on the contralateral side if you cannot achieve an MIO >35 mm and/or to the point of dislocation of the unaffected TMJ.

Lining of the TMJ with a temporalis myofascial flap or the native disk (if salvageable).

Reconstruction of the ramus condyle unit with either distraction osteogenesis (DO) (activate 2–4 days) or CCG and rigid fixation (10 days of MMF (Maxillary-Mandibular Fixation). If DO is used to reconstruct the ramus condyle unit, reshape the native bone narrowed and rounded. A corticotomy is then created distally to serve as transport disk. The distraction is set at 1 mm/day. Mobilization begins the day of the operation. In patients who undergo CCG reconstruction, mobilization begins after 10 days of MMF. DO takes advantage of the fibrocartilaginous cap that forms on the advancing front of the distracted bone heading toward the fossa.

Early mobilization of the jaw.

Aggressive physiotherapy.

Aggressive physical therapy is paramount in the treatment.

Frequent follow-up.

Consider radiation therapy (20 Gray in 10 fractions) to prevent recurrence and consider when using autogenous grafting, as the risk of recurrence is higher.

The CCG is commonly used in the growing child. It offers many advantages including ease of adaptation and remodeling, low morbidity at the harvest site, low rate of infections, and reduced relative cost. It does, however, increase operating time. In adults 12–17 cm of rib can be harvested and 7–10 cm in children within the borders of the lateral edge of the latissimus dorsi and costochondral junction.

Ribs 4–7 may be harvested as they have a direct cartilaginous connection to the sternum. Rib 6 is the most commonly harvested as the incision falls in the inframammary crease creating a better cosmetic outcome (fusion of the rectus and pectoralis major forms an avascular plane.) It is common practice to harvest the right rib, as it is least likely to be confused with cardiogenic pain. Many advocate the rib contralateral to the side of the defect to allow appropriate curvature of the harvested rib.

A sharp incision is made in the inframammary crease (5 cm long).

Dissection is carried through the subcutaneous tissue, fascia, and the plane between the pectoralis major and rectus abdominis.

Two fingers are used to straddle the fifth and sixth intercostal space to prevent slipping of instruments. A sharp incision is cut through the periosteum down to the outer cortex of the rib.

A molt periosteal now can be used to dissect in a subperiosteal plane around the rib. Some surgeons used the Doyen rib stripper, but its usage is known to be associated with parietal pleural tears.

A sharp blade is used to make the cartilaginous incision. In children it is important to harvest no more than 3 cm (no less than 1 cm) to avoid overgrowth of the rib and to prevent separation of the cartilaginous cap.

The rib is pulled laterally and a protected rib cutter is now used to section the length of desired rib.

Check for pleural tears by filling the cavity with normal saline and have the anesthesiologist perform a Valsalva maneuver to check for bubble formation.

The periosteal sleeve is now closed with 3-0 polyglactin (this may promote de novo regeneration of the missing rib in the child patient).

The fascia between the rectus and pectoralis major is closed with a 3-0 resorbable suture, followed by subcutaneous tissue and finally skin.

Post-operatively a chest X-ray is ordered to rule out a missed pneumothorax or hemothorax. The patient may return to normal activity post-op day 7, but any strenuous activity is withheld for 6 weeks.