Key points
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Association between temporomandibular disorder (TMD) and sleep disturbances, including obstructive sleep apnea (OSA), is well documented, although the underlying mechanisms remain unclear.
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Comprehensive diagnostic workup is critical in determining the appropriate selection of surgical options for patients with both OSA and TMD.
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Patients with TMD and OSA who are intolerant of medical therapies can be treated effectively with custom temporomandibular joint (TMJ) reconstruction in combination with maxillomandibular advancement (MMA).
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Virtual surgical planning is an accurate method to optimize MMA movements in setting of TMJ reconstruction.
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A detailed step-by-step protocol is essential to minimize intraoperative complications.
Introduction
Obstructive sleep apnea (OSA) is characterized by repeated collapse of the upper airway and cessation of breathing that leads to arousals and results in comorbidities, such as hypertension, stroke, myocardial infarction, and diabetes. OSA has emerged as a medical condition that has considerable health and social repercussions. Temporomandibular joint (TMJ) disorders, such as degenerative joint disease, are characterized by pain and joint dysfunction that can lead to progressive condylar resorption and mandibular retrognathia, resulting in a malocclusion with anterior open bite and airway compromise. The association between temporomandibular disorder (TMD) and sleep disturbances, including OSA, is well documented, although the underlying mechanisms remain unclear.
Patients with OSA who are intolerant of positive airway pressure therapy can be treated with maxillomandibular advancement (MMA) with high success rates. However, there is a subset of OSA patients who also present with TMD that needs to be addressed to provide a stable and predictable outcome. Temporomandibular joint reconstruction (TJR) using custom prostheses in conjunction with orthognathic surgery has been used to treat TMD and craniofacial anomalies. Bilateral TJR with concomitant MMA surgery is the solution that allows surgeons to treat both TMD and OSA simultaneously.
The surgeon needs to have a thorough understanding of the preoperative and surgical protocols in order to enable efficiency, limit operative time, and deliver optimal postoperative outcomes. This article describes the steps required for preoperative assessment, virtual surgical planning (VSP), and performance of the bilateral TMJ reconstruction with MMA to treat TMD and OSA concurrently.
Surgical technique
Diagnostic workup
A comprehensive diagnostic workup is critical in determining the appropriate selection of surgical options for patients with both OSA and TMD. The severity of pathologic condition associated with OSA and TMD will determine whether both pathologic conditions need to be surgically treated concomitantly versus one treated medically and the other surgically. Conservative medical treatment is always initiated first for each disorder. If conservative treatment allows for resolution of symptoms and stabilization of one of the pathologic conditions, then the other can be solely addressed surgically. Therefore, it is important to look at each disease as separate entities and also as synergistic processes. Indications for concomitant TJR and MMA include moderate to severe OSA and TMJ disorders, such as articular disc displacement, condylar resorption, ankylosis, congenital malformation, and arthritic changes.
Obstructive sleep apnea
Patients require a thorough clinical examination of the nasal passages, oropharyngeal space, and retroglossal area, taking note of the nasal septum, turbinates, uvula, soft palate, tonsils, tongue size and positioning, occlusal classification, and relative positioning of the maxilla and mandible. A baseline polysomnography (PSG) or home sleep study is needed to characterize the severity of the OSA according to the standards of the American Academy of Sleep Medicine. Radiographic evaluation of the airway includes a computed tomographic (CT) scan and lateral cephalometric analysis. A choke point of less than 50 mm 2 is associated with severe OSA, and greater than 150 mm 2 is generally normal. Drug-induced sleep endoscopy (DISE) is a tool to identify areas of collapse and patterns of obstruction along the airway while the patient is asleep. DISE provides data to develop an accurate diagnosis and prescribe specific surgical treatments targeted to correct the anatomic problem areas. The pattern and degree of collapse are scored according to the VOTE (velum, oropharyngeal, tongue base, and epiglottis) classification.
Temporomandibular joint disorder
Patients require a detailed assessment of the functionality of the TMJ region, which includes palpation of the muscles of mastication and condyle, auscultation of the TMJ for clicking, popping, and crepitus, measuring the range of motion including maximum incisal opening, lateral excursive movements, deviation on opening and closing, and occlusal classification and stability. Radiographic evaluation includes a CT scan to look at joint space and condylar degenerative changes and an MRI to look for joint effusions and disc integrity and position in the open and closed mouth position.
These various diagnostic modalities should be used together to provide a comprehensive airway and TMJ evaluation to select an appropriate surgical treatment option.
Preoperative planning
Preoperative planning steps use virtual surgical technology. The custom, patient-specific TMJ prostheses are manufactured by TMJ Concepts (Ventura, CA, USA).
- 1.
CT scan and dental casts sent with bite registration to the VSP company of choice ( Fig. 1 )
Fig. 1 ( A , B ): Dental casts with bite registration and CT scan are sent to the VSP company for MMA planning. - 2.
Models scanned and incorporated into CT scan
- 3.
Virtual removal of condyles and ramus
- 4.
Computer-aided planning session for final positioning of the maxilla and mandible with mandible surgery as the first approach ( Fig. 2 )
Fig. 2 Dental models are scanned and incorporated into the CT image. Virtual surgical workup competed with final positioning of the maxilla and mandible (maxilla and mandible have been advanced and rotated counterclockwise). - 5.
Final approval of jaw positions: VSP company fabricates intermediate and final splints
- 6.
Finalized virtual planning data sent to TMJ Concepts
- 7.
Stereolithic model constructed with jaws in final position, and TMJ Concepts performs design and wax-up of TMJ prostheses
- 8.
Images of TMJ design and wax-up sent to surgeon for approval ( Fig. 3 )
Fig. 3 ( A , B ) Right ( A ) and left ( B ) wax-up of the fossa and condyle by TMJ Concepts. (Ventura, CA) - 9.
TMJ Concepts manufactures custom fossa and condylar prostheses ( Fig. 4 )
Fig. 4 ( A , B ) Fabricated right ( A ) and left ( B ) TMJs with the incorporated mandibular advancement. - 10.
Stereolithic model and TMJ prostheses (TMJ Concepts) and splints with dental models (VSP company) are sent to surgeon ( Fig. 5 )
Fig. 5 ( A , B ) Stereolithic model and TMJ prosthesis and splints with dental models sent to the surgeon.
Preparation and patient positioning
The patient is taken to the operating room, placed in the supine position, and intubated nasally. If orthodontic brackets and bands were not applied preoperatively, then traditional Erich or hybrid arch bars are placed. Bilateral Nerve Integrity Monitoring System probes (Medtronic, Minneapolis, MN, USA) are placed to monitor the branches of the facial nerve ( Fig. 6 ). The external auditory canals are irrigated with around 300 ml of a 1:1 ratio of betadine and saline. The face and abdomen are then prepared with betadine and isolated with sterile towels and split sheet ( Fig. 7 ). The mouth is isolated with Tegaderm (3M, St. Paul, MN, USA); gauze impregnated with petroleum jelly is placed in each ear canal, and the tragus is sutured closed. Then, 1010 drapes (3M) are placed to further isolate the oral cavity from the surgical field. The patient is given decadron and intravenous (IV) antibiotics before the start of the surgical procedure.
Surgical procedure
- 1.
Bilateral TMJs are approached via a preauricular or endaural incision down through skin and subcutaneous tissue. A flap is raised above the supramuscular aponeurotic system (SMAS) and sutured anteriorly. The dissection continues just anterior to the tragal cartilage through the SMAS down to the level of the superficial layer of the temporalis fascia. A 2-cm incision is made through the temporalis fascia to expose the zygomatic arch and zygomatic root. Dissection is carried anteriorly along the arch to expose the eminence ( Fig. 8 ).
Fig. 8 ( A , B ) Dissection through the temporalis fascia to expose the zygomatic arch and eminence. - 2.
An incision is made through the capsule down to the condyle. Condylar retractors are placed anteriorly and posteriorly to aid in visualization of the condylar neck. An osteotomy using BoneScalpel (Misonix, Farmingdale, NY, USA) is made through the condylar neck to minimize blood loss ( Fig. 9 ). The condylar head and articular disc are removed.
Fig. 9 BoneScalpel (top instrument; Misonix, Farmingdale, NY), piezoelectric device that preferentially cuts bone instead of soft tissue, is used to cut through the condylar neck to minimize blood loss. - 3.
The submandibular incision is marked, and dissection is carried through skin, subcutaneous tissue, and superficial layer of the deep cervical fascia. The entire mandibular ramus is exposed up to the condylar neck, sigmoid notch, and coronoid. From the preauricular wound, an osteotomy is made 5 mm inferior to the sigmoid notch, across the coronoid and remaining condylar neck. The temporalis muscle is dissected off the coronoid process, and the bony complex is completely removed ( Fig. 10 ).
Fig. 10 Complete removal of the right condyle, coronoid process, and articular disc. - 4.
The surgical steps outlined thus far are then carried out on the contralateral joint.
- 5.
While maintaining a sterile field with additional towels, one member of the surgical team places the patient into intermaxillary fixation (IMF) using the intermediate occlusal splint. The contaminated towels are removed, and the mouth is again isolated with Tegaderm and 1010 drapes. The surgeon then rescrubs into the case.
- 6.
Reconstruction is first focused on one of the TMJs, which includes insetting of the fossa and condylar prostheses, fat graft placement, and closure before starting on the contralateral side. This minimizes time of prosthetic exposure and possibility of infection.
- 7.
The custom fossa prosthesis is placed and secured with 4 screws, after removal of bony interferences at the eminence and fossa, if indicated on the stereolithic model. Next, the mandibular prosthesis is positioned so that it is flush on the ramus, and so that the condylar component is seated in the posterior aspect of the prosthetic fossa. The mandibular component is then secured with 6 screws ( Fig. 11 ).
Fig. 11 Inset of the right fossa and condylar prosthesis. - 8.
Fat graft is harvested from the abdomen at the lateral aspect, the umbilical area, or suprapubic region. A 2-cm incision is made through the skin and subcutaneous tissue, and fat is removed. The site is irrigated and closed after hemostasis is achieved.
- 9.
The TMJ surgical site is irrigated; the fat graft is packed around the TMJ prosthesis ( Fig. 12 ), and the incisions are closed in layers. The contralateral TMJ fossa and condylar prosthesis are next placed, packed with fat graft, and closed in a similar fashion.
Fig. 12 Fat graft packed around the TMJ prosthesis. Good-quality abdominal fat is easy to procure and very beneficial for the prevention of heterotopic bone. - 10.
The patient is released from IMF, and the intermediate splint is removed. Attention is directed to the maxillary surgery.
- 11.
A K-wire is placed at level of nasion, and preoperative measurements with calipers are taken from K-wire to reproducible areas on the bilateral first molar, canine, and central incisors. Preoperative alar base is also measured.
- 12.
A standard Le Fort I osteotomy is carried out. The incision is made through the maxillary vestibule from second premolar to contralateral premolar. A periosteal elevator is used to expose the anterior maxilla and lateral maxillary walls to the level of the pterygoid plates. The nasal mucosa is elevated from the piriform rim, lateral nasal wall, and nasal floor.
- 13.
The maxillary osteotomy is cut from the buttress to the piriform rim. Interdental cuts are completed before downfracture of maxilla if multipiece maxillary osteotomy is indicated.
- 14.
A double-guarded osteotome is used to separate the nasal septum from the nasal crest of the maxilla. A curved osteotome is used to divide the pterygoid-maxillary junction. A single guarded osteotome is used to cut through the lateral nasal wall.
- 15.
The maxilla is downfractured and mobilized. Segmental osteotomies are then completed as indicated.
- 16.
The final occlusal splint is inserted, and the maxilla is advanced to meet the newly positioned mandible and secured with IMF. The maxillomandibular complex is rotated counterclockwise, and bony interferences are removed to ensure adequate bony contact. Calipers are used to measure from the K-wire to the reproducible areas on the bilateral first molar, canine, and central incisors, and planned movements are confirmed, including elimination of a cant. The maxilla is rigidly fixated with 4 bone plates, one at the piriform region and one at the buttress bilaterally ( Fig. 13 ). The alar base cinch suture is placed using 2-0 PDS suture and tightened to match the preoperative measurement. The maxillary incision is closed in a V-Y design to increase the upper lip length.
Fig. 13 Final splint has been placed and secured with IMF. The maxilla has been advanced, rotated counterclockwise, and rigidly fixated with plates and screws. - 17.
Additional procedures, such as genioplasty, turbinectomy, and lateral expansion pharyngoplasty, may be performed ( Fig. 14 ).
Fig. 14 Adjuvant procedures such as genioglossus advancement may be performed if indicated.
Surgical technique
Diagnostic workup
A comprehensive diagnostic workup is critical in determining the appropriate selection of surgical options for patients with both OSA and TMD. The severity of pathologic condition associated with OSA and TMD will determine whether both pathologic conditions need to be surgically treated concomitantly versus one treated medically and the other surgically. Conservative medical treatment is always initiated first for each disorder. If conservative treatment allows for resolution of symptoms and stabilization of one of the pathologic conditions, then the other can be solely addressed surgically. Therefore, it is important to look at each disease as separate entities and also as synergistic processes. Indications for concomitant TJR and MMA include moderate to severe OSA and TMJ disorders, such as articular disc displacement, condylar resorption, ankylosis, congenital malformation, and arthritic changes.
Obstructive sleep apnea
Patients require a thorough clinical examination of the nasal passages, oropharyngeal space, and retroglossal area, taking note of the nasal septum, turbinates, uvula, soft palate, tonsils, tongue size and positioning, occlusal classification, and relative positioning of the maxilla and mandible. A baseline polysomnography (PSG) or home sleep study is needed to characterize the severity of the OSA according to the standards of the American Academy of Sleep Medicine. Radiographic evaluation of the airway includes a computed tomographic (CT) scan and lateral cephalometric analysis. A choke point of less than 50 mm 2 is associated with severe OSA, and greater than 150 mm 2 is generally normal. Drug-induced sleep endoscopy (DISE) is a tool to identify areas of collapse and patterns of obstruction along the airway while the patient is asleep. DISE provides data to develop an accurate diagnosis and prescribe specific surgical treatments targeted to correct the anatomic problem areas. The pattern and degree of collapse are scored according to the VOTE (velum, oropharyngeal, tongue base, and epiglottis) classification.
Temporomandibular joint disorder
Patients require a detailed assessment of the functionality of the TMJ region, which includes palpation of the muscles of mastication and condyle, auscultation of the TMJ for clicking, popping, and crepitus, measuring the range of motion including maximum incisal opening, lateral excursive movements, deviation on opening and closing, and occlusal classification and stability. Radiographic evaluation includes a CT scan to look at joint space and condylar degenerative changes and an MRI to look for joint effusions and disc integrity and position in the open and closed mouth position.
These various diagnostic modalities should be used together to provide a comprehensive airway and TMJ evaluation to select an appropriate surgical treatment option.
Preoperative planning
Preoperative planning steps use virtual surgical technology. The custom, patient-specific TMJ prostheses are manufactured by TMJ Concepts (Ventura, CA, USA).
- 1.
CT scan and dental casts sent with bite registration to the VSP company of choice ( Fig. 1 )
