Orthodontic & tmd by almuzian

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Orthodontic & tmd by almuzian

  1. 1. UNIVERSITY OF GLASGOW Orthodontics, TMD & TMJ Ankylosis Personal notes Mohammed Almuzian ……… …..
  2. 2. Contents Contents...................................................................................................................................2 Introduction..............................................................................................................................4 It is better to start with some introduction before going ahead and discuss this topic in details.......................................................................................................................................5 Anatomy of TMJ .......................................................................................................................5 Physiology of the TMJ's.............................................................................................................7 Disorders of the TMJ's..............................................................................................................7 Condition..................................................................................................................................8 Example ...................................................................................................................................8 Comments.................................................................................................................................8 Temporomandibular Dysfunction (TMD)................................................................................10 Aetiology.................................................................................................................................11 Incidence of TMD ...................................................................................................................11 Measurement of TMD ............................................................................................................12 Examination of TMD...............................................................................................................13 Evidences of the Relationship between TMD, Orthodontics, occlusal interferences & malocclusion...........................................................................................................................14 Problems with TMJ research...................................................................................................16 Orthodontist’s role in the management of TMD ....................................................................17 BOS guidelines for management of TMD...............................................................................20 What are the main treatments available for TMD?................................................................20 In details…………………..............................................................................................................22 Limited mouth opening (Trismus) ..........................................................................................27 Presentation of Ankylosis.......................................................................................................28 Diagnosis of for ankylosed TMJ ..............................................................................................28 Mohammed Almuzian, University of Glasgow, 2013 2
  3. 3. Treatment Choices .................................................................................................................29 Surgical Approach and preparation .......................................................................................30 Complications ........................................................................................................................30 Mohammed Almuzian, University of Glasgow, 2013 3
  4. 4. Orthodontics, TMD & TMJ Ankylosis Introduction • Interest was aroused in 1987 following litigation in America; the case was that of Brimm vs. Malloy and is described in more detail, by an attorney in: Pollack B. Cases of note: Michigan jury awards $850,000 on orthodontic case: a tempest in a teapot. (Am J Orthod Dentofacial Orthop 1988; 94: 358-60). A patient developed symptoms of a temporomandibular disorder (TMD) during orthodontic treatment and the case went against the orthodontist, resulting in almost a million dollars being paid out. • At the BOS Spring Meeting in 1997, the well-known American academic Lysle Johnston explained that originally the claim was that the patient had not received appropriate management when TMD symptoms had first started in treatment and that there had been inadequate pre-treatment documentation of the patient's TMD status. Ultimately however, the orthodontic treatment itself was blamed for causing the patient's TMD. One of the main reasons for this was the lack of evidence to suggest that orthodontics had not caused the problem (Giannelly, 1989). • This was confirmed by Reynders (1990) who reviewed relevant studies spanning the period 1966 - 1988 and found that of 91 relevant papers, 55 were view point articles, 30 were case reports but only 6 were sample studies. Worse still, half of the case reports were written by one author and these were published in one journal - of which that author was the editor. Mohammed Almuzian, University of Glasgow, 2013 4
  5. 5. It is better to start with some introduction before going ahead and discuss this topic in details. Anatomy of TMJ The TMJs are the only freely movable (synovial) articulations in the skull apart from the joints between the ossicles of the middle ear. The TMJ consists of: 1. Articular surfaces (of the condyle and the Glenoid fossa): • The TMJ is formed between the articular surfaces of the squamous part of the temporal bone and of the condyle of the mandible. • The articular surfaces are covered by fibrocartilage. • Beneath the articular covering of the condyle is a layer of hyaline cartilage (sometimes referred to as the condylar cartilage). It is an important growth site which is more readily apparent in the immature mandible. 2. Capsule: • A fibrous capsule is attached above to the squamous bone around the margin of the upper articular surface, and below to the neck of the mandible. • The capsule is slack between the articular disc and the squamous bone but much tighter between the disc and the neck of the mandible. Mohammed Almuzian, University of Glasgow, 2013 5
  6. 6. • The lateral pterygoid muscle is inserted, in part, into the anterior surface of the capsule. 3. Articular disc: • It is a plate of fibrocartilage which in the majority of cases completely divides the joint cavity into upper and lower compartment. • Laterally and medially the disc blends with the capsule of the joint. • In front, it is attached to the capsule and the lateral pterygoid muscle. • Posteriorly the disc is divided into two layers. The upper layer is attached to the anterior margin of the squamotympanic fissure while the lower layer is attached to the posterior surface of the neck of the mandible. • The upper surface of the disc is slightly concave anteriorly and markedly convex posteriorly. The under surface is concave over its whole extent. • The disc is not uniform thickness. The central part is the thinnest and is relatively avascular 4. Ligaments: • The capsule is strengthened laterally by a thick band of fibrous tissues, the lateral temporomandibular ligament. • The sphenomandibular and stylomandibular ligament are described as accessory ligaments of the TMJ. 5. Synovial membrane: • The internal aspect of the capsule, the non-articular surfaces of the mandibular neck and to a variable extent, the peripheral areas of the Mohammed Almuzian, University of Glasgow, 2013 6
  7. 7. articular disc is covered with a layer of the synovial membrane which provide nourishment for the joint structures. 6. Nerve and Blood supply: • The deep temporal and masseteric branches of the maxillary artery and the branches of the superficial temporal artery, which arise from the external carotid artery, supply the TMJ. • Venous drainage is via the superficial temporal, maxillary, and pterygoid plexus of veins. • The capsule of the TMJ is innervated from a large branch of the auriculotemporal nerve. The anterior region of the joint is innervated from the masseteric nerve and from the posterior deep temporal nerve. The articular cartilage and the central part of the disk contain no nerves Physiology of the TMJ's There are two basic movements of the TMJ's: • Hinge movement occurs in the first stages of opening. Here the condylar head remains in the glenoid fossa. • Translation occurs as the condylar head moves down the articular eminence. It relies on coordinated movement between the condyle and the disc. In some TMJ conditions the disc and condyle do not move together for example in anterior disc displacement Disorders of the TMJ's The British Association of Oral and Maxillofacial surgeons describe two groups of patients presenting with TMJ problems: Mohammed Almuzian, University of Glasgow, 2013 7
  8. 8. Condition Example Comments Those with abnormal anatomy whose function may be abnormal. Congenital or developmental disorders Aplasia Very rare - where no condyle forms at all Hypoplasia/ Hyperplasia These can lead to progressive facial asymmetry Neoplastic Neoplasia Extremely uncommon Inflammatory disorders Synovitis and capsulitis Localised pain associated with trauma, infection or immunological conditions Rheumatoid arthritis and other auto immune diseases Systemic conditions affecting the TMJ's Degenerative or Age related problems Osteoarthritis Degenerative joint disease, leads to abrasion of the joint surfaces and remodeling. Characterised by crepitation. Traumatic Ankylosis Long term sequela of trauma Fracture Caused by trauma TMJ dislocation: Acute or chronic. The chronic type is associated in most of the cases with some degenerative disorders acute dislocation occurs when the Mohammed Almuzian, University of Glasgow, 2013 8
  9. 9. patient is hit with the mouth open Those with normal anatomy but abnormal function Dysfunctional Disc displacement with reduction Where the disc clicks back into place part way through translation Disc displacement without reduction Where the disc remains permanently displaced anteriorly Temporomandibular Dysfunction (TMD). See below Mohammed Almuzian, University of Glasgow, 2013 9
  10. 10. Temporomandibular Dysfunction (TMD). It refers to a collection of conditions affecting the temporomandibular joint (TMJ) and its related structures, including the muscles of mastication. The term TMD can describe symptoms such as:- I. Pain related signs and symptom: • Pain in the face or jaw joint area • Headaches • Earaches II. Extra oral signs and symptom: • Masticatory muscle hypertrophy III. Functional signs and symptom: • Clicking or popping sounds from the jaw joint, • Limited opening or closed lock of the TMJ • Reduced lateral mandibular excursions IV. Intra oral signs and symptom: • Abnormal occlusal wear • Lina alba buccalis Mohammed Almuzian, University of Glasgow, 2013 10
  11. 11. Aetiology A. Old theories regarding the aetiological factors that may cause TMD independently 1. Factors within the central nervous system: as the emotional stresses. 2. Social conditions: an increased level of anxiety, which may lead to increased muscle tension. 3. Occlusal interference: such as anterior open bite, crossbites, reverse overjet, parafunctional activity…etc. 4. Trauma. 5. Internal joint pathology eg disc displacement / destruction. Proffit, 1993 6. Orthodontic treatment: such as changing the condyle position and changing vertical face height. 7. Orthognathic surgery. B. New philosophy: Mohlin & Thilander, 1984 described the new opinion about the aetiology of TMD. It is Multifactorial reason: 1. Psychological 2. Dysfunctional 3. Inflammatory 4. Degenerative 5. Idiopathic Incidence of TMD A. Proffit (2002) suggests levels of between 5-30% depending on the symptoms examined for TMD.(this variation because the studies have no standardization in their method of assessment) Mohammed Almuzian, University of Glasgow, 2013 11
  12. 12. B. It has also be noted that TMD increases with age, Egermark-Ericson et al (1983) suggesting an increase in the prevalence of symptoms from 30% to 60% (two times) between the age of 20 and 45 years. C. Females have higher prevalence due to (Warren and Fried, 2001): • Physiological differences • Anatomical differences • Behavioural differences • Genetic differences. Measurement of TMD Studies investigating TMD have used indices: 1. Helkimo Clinical Dysfunction Index. (HCDI) The following are scored: • TMJ sounds, • Symptoms of reduced movement capacity • Locking or luxation of the mandible, • Deviation on opening, • Pain on movement, • Muscle and TMJ tenderness. Each symptom is judged according to a three grade scale. Problems with the use of this index are described (Van der Weele and Dibbets 1987) including insufficient evidence to support or to document the validity of this index. This index contains useful elements and should be adapted rather than replaced to improve its' validity Mohammed Almuzian, University of Glasgow, 2013 12
  13. 13. 2. Craniomandibular index CMI (Fricton and Schiffman, 1987) Index has had little use in the orthodontic literature but it addresses the problems of validity and reproducibility associated with Helkimo Index. Examination of TMD History: • Before any clinical examination, the patient should be asked about symptoms such as pain, clicking, crepitus or locking of the jaw. • Ask the patient about any previous treatment that he/she had for the TMJ such as medications, splints, occlusal adjustments, physical therapy or surgery. Clinical Examination: • The joint should be palpated simultaneously by placing the middle finger over the condylar head whilst the patient is instructed to open and close and to move laterally. Any clicks, crepitus, and locking should be recorded. It is probably prudent to record any negative findings as well. • The muscles of mastication should also be examined for areas of tenderness. Special Tests: 1. Mounted study models 2. Radiographs 3. If problems persist MRI and arthrogram may be considered Mohammed Almuzian, University of Glasgow, 2013 13
  14. 14. Evidences of the Relationship between TMD, Orthodontics, occlusal interferences & malocclusion With Against A. Correlation between occlusal interference, malocclusion and TMD There are weak evidences by (Thilander et al., 2002) regarding the association between TMD and the following malocclusion traits: • AOB • Deep OB • Excess OJ (either CI II or III) • Posterior crossbite, • • Proffit (2002) only 5-30% of individuals have TMD yet 50-75% has at least a moderate malocclusion. • Luther (1998) Notes there may be a weak association between TMD, AOB, Class III malocclusion, crossbite and nonworking-side contacts. • Occlusal interferences and TMD, Magnusson & Enbom, 1984 signs and symptoms of TMD are two times more in a group of subjects with artificially induced non- working side interferences compared with controls Sadowsky & BeGole, 1980 non- working side contacts are common and not relate to the development of TMD. B. Orthodontics as a curative methods for TMD • Proffit (1999) believes that orthodontic treatment causes the periodontal ligament to become temporarily painful which reduces any bruxing habits and therefore • Egermark et al., 2003, 2005, 20 yr follow-up: orthodontic treatment in childhood does not reduce the risk of developing TMD. Mohammed Almuzian, University of Glasgow, 2013 14
  15. 15. rests the TMJs, in turn this reduces the TMD symptoms. • TMD reduced in patients having fixed appliances (Sadowsky and BeGole, 1980). This reduction was not statistically significant. C. Orthodontics as a causative factor for TMD Roth, 1973 thought that condylar position can be altered with the aid of some mechanics: • Elastics • Retraction of the ULS • HG to the maxilla • HG to the mandible • Chin cap Johnston & Luecke, 1992 orthodontic treatment does not force the condyle distally, in fact it moves temporarily forwards 0.7mm (in 70%), movement due to loss of anchorage in buccal segments. Other believed that the TMJ disc position can be altered by orthodontic treatments leading to TMD. Kircos et al., (1987) there appears to be no evidence that the TMJ disc position can be altered by orthodontics. Even if it does but there is no strong correlation between disc position, clicking and TMD. Extraction force the condyle distally and trap the disc anteriorly Witz and Yertz, 1985. The frequency of TMD symptoms is the same in groups of extraction and non-extraction cases (Paquette et al., 1992; Luppanapornlarp and Johnson, 1993). Orthognathic treatment can cause Orthognathic surgery does not Mohammed Almuzian, University of Glasgow, 2013 15
  16. 16. change of the condyle position leading to TMD. necessarily increase or decrease the signs/symptoms of TMD, Egermark et al., 2000 • Cochrane review by Luther 2010: There are insufficient research data on which to base our clinical practice on the relationship of active orthodontic intervention and TMD. There is an urgent need for high quality randomised controlled trials in this area of orthodontic practice. Problems with TMJ research Reynders, 1990 • Many viewpoint publications and case reports but relatively few sample studies. • Biased case sampling • Inappropriate or non-existent control groups • Inadequate design ie not matched for ethnic background, socio- economic status, sex, inter observer variability, types of appliances, age etc • Incomplete or inaccurate data collection • Unjustified assumptions • Faulty interpretation Mohammed Almuzian, University of Glasgow, 2013 16
  17. 17. Orthodontist’s role in the management of TMD Also the evidence seems to suggest that orthodontics has no effect on TMJ, but TMD could be present or appear during treatment, therefore certain protocols should be followed. Pre-treatment. 1. Full history. 2. Any signs or symptoms of TMD should be noted 3. If the patient already has a TMD, then the patient informed that orthodontic treatment has no influences according to the evidence based literatures. 4. If the condition is sever and acute it is better not to commence orthodontic treatment until the condition is stabilized by a specialist. During treatment If TMD manifest’s during treatment, a number of steps can be taken. 1. Initially reassure the patient that TMD is not necessarily a progressive problem and for many, symptoms spontaneously improve over time. 2. An explanation of the relationship with stress (e.g. can get worse around exam time) is also useful. 3. Modify the treatment. • Reduce forces on headgear, Mohammed Almuzian, University of Glasgow, 2013 17
  18. 18. • Remove or lighten elastics. • Eliminate occlusal interferences by using a bite plane. 4. Advice on some practical measures can include: • Resting the joint - e.g. avoiding over opening during wide yawning etc. • Soft diet - some patients find certain foods will trigger symptoms. • Analgesics - e.g. non-steroidal anti-inflammatory drugs (if not otherwise contraindicated). • Application of heat - e.g. a heat pack can be used to relax muscles. 5. Suspend treatment • If symptoms continue treatment such be suspended 4. Referral. • If following cessation of treatment and conservative measures, the patient may need referral to a specialist in TMD. • Then the TMD might managed by the specialist with conservative measures, soft diet, muscle relaxants, analgesics, occlusal splint or surgery. Post treatment The patient should be monitored through out Mohammed Almuzian, University of Glasgow, 2013 18
  19. 19. retention for the signs and symptoms of TMD. Mohammed Almuzian, University of Glasgow, 2013 19
  20. 20. BOS guidelines for management of TMD What are the main treatments available for TMD? Mohammed Almuzian, University of Glasgow, 2013 20
  21. 21. 1. Patient education and self-care 2. Home physiotherapy programme • Massage • Exercise • Short Wave Diathermy • Ultrasound • Laser 3. Behavioural intervention • Stress management • Counselling • Cognitive Behavioural intervention • Hypnosis 4. Pharmacology • NSAID's • Corticosteroids • Hypnotics/Anxiolytics/Tricyclic antidepressants 5. Splint Therapy • Soft splints • Localised occlusal interference splint • Anterior bite plane • Anterior repositioning splint • Stabilisation splint Mohammed Almuzian, University of Glasgow, 2013 21
  22. 22. 6. Occlusal equilibration 7. TMJ surgery • Arthocentesis • Arthroscopy • Arthrotomy In details………………….. A. Patient education and self-care Self-care = resting the masticatory system (habit awareness and modification). B. Home physiotherapy programme • Massage: Increases blood flow, relaxes muscles • Exercise: Mobilisation can be used when there is decreased range of motion due to muscle contracture, disc displacement without reduction or fibrous adhesions in the joint • Short Wave Diathermy: Thermal stimuli increased blood flow to increase oxygenation and metabolite removal. • Ultrasound: The sound waves produce pressure waves in the tissue resulting in micro massage Mohammed Almuzian, University of Glasgow, 2013 22
  23. 23. • Laser: Laser treatment does not increase the tissue temperature but is thought to increase capillary permeability and stimulate fibroblast production C. Cognitive Behavioural intervention • Stress management • Counselling • Hypnosis D. Pharmacology • Analgesics like (NSAID's) • Corticosteroids, these are not usually prescribed for systemic use in TMD treatment because of their side effects. The exception is for acute generalised muscle and joint inflammation associated with polkyarthrides. Intracapsular steroid injections have been recommended on a limited basis in cases of severe joint pain where conservative treatment has been unsuccessful. • Hypnotics/Anxiolytics/Tricyclic antidepressants have been shown to be effective for short-term management (1-2 weeks) especially for bruxism. E. Splint Therapy Splints are the widely used as a treatment in the UK. Types of splints: • Soft splints • Localised occlusal interference splint Mohammed Almuzian, University of Glasgow, 2013 23
  24. 24. • Anterior bite plane • Anterior repositioning splint • Stabilisation splint In details ….. 1. Soft splints - these are usually made of a vacuum formed polyvinyl material. They can be thought of as a simple emergency treatment for patients with symptoms of TMD e.g. the student with an acute pain around exam time. Their mode of action is unclear - they may simply be a habit breaker but there is a risk that it can induce more parafunctional activity. 2. Localised occlusal interference splint - this is an acrylic splint with ball clasps that deliberately places the entire occlusal load on 4 teeth so as to overload the proprioceptive fibres and break clenching or grinding habits. It is meant to be worn by grinders at night or at other times when they may parafunction e.g. whilst driving. 3. Anterior bite plane (Lucia jig). This is a deprogramming splint, made at the chairside for emergency (short-term) treatment of patients with acute muscle spasm and pain. The aim is to provide ideal anterior guidance and to dis-occlude the posterior teeth. 4. Anterior repositioning splint - a hard acrylic splint fitted on the lower teeth used to treat anterior displacement with reduction. The mandible is postured forwards (a little like a functional appliance) which keeps the disc in the correct position on the condylar head in order to achieve 'click free' opening and closing. Short term these can work well in reducing symptoms, but one questions how they can work long-term? Mohammed Almuzian, University of Glasgow, 2013 24
  25. 25. 5. Stabilisation splint (Tanner appliance, Fox appliance, Michigan Splint, Centric Relation Appliance) - a hard acrylic splint constructed on a semi adjustable articulator and ground in in the mouth. This splint is intended to provide a temporary ideal functional occlusion. It is likely that like all other splints it is a habit breaker. Some clinicians consider the success of a stabilisation splint to be an indication that orthodontic treatment or occlusal equilibration may be successful. Cochrane review by Al Ani 2009 found no evidence regarding the advantage of splint in treatment of TMD F. Occlusal equilibration • It has long been recommended for the treatment of TMD • This is the is the removal of non-working side contacts by selective grinding Cochrane review by Koh 2009 Occlusal adjustment cannot be recommended for the management or prevention of TMD G. TMJ surgery • Non-invasive measures are preferred to surgery for the treatment of TMD. • Surgery may be considered if conservative measures fail or if pathology e.g. neoplasia is suspected. • The surgeries include: Arthocentesis, Arthroscopy and Arthrotomy Type of Surgery What does it involve? When is it used? Is it Successful? Arthocentesis Intra-articular For intra-articular Thought to be Mohammed Almuzian, University of Glasgow, 2013 25
  26. 26. irrigation with or without steroids. Often used with joint mobilisation joint restrictions equally as effective as arthroscopy in anterior disc displacement without reduction Arthroscopy Insertion of a camera into the joint (usually upper joint space). Allows direct observation and can then also irrigate, debride, incise minor adhesions and take biopsies. As above Further research needed but no better than physio in improving range of movement or decreasing pain. Arthrotomy Open surgical intervention E.g.: discoplasty, discal repositioning, discectomy (with or without replacement), arthroplasty (recontouring of the articular surfaces with or without Bony or fibrous ankylosis, neoplasia, severe chronic dislocations, persistent painful disc derangement, severe osteoarthritis, Less commonly - displaced condylar Variable success. Alloplastic disc replacements are now contraindicated and it has actually been recommended that all Proplast implants are actually removed Mohammed Almuzian, University of Glasgow, 2013 26
  27. 27. removal of the disc), high condylectomy fractures Limited mouth opening (Trismus) There are many causes of limited mouth opening which may be classified as follows. 1. Intra-articular (intracapsular) • Functional: Anterior displacement of the meniscus without reduction. • Trauma: Osseous or fibro-osseous ankylosis, secondary to trauma • Inflammatory: Ankylosing spondylitis, juvenile rheumatoid arthritis. • Infection in the joint. • Tumour of the joint structures. 2. Extra-articular (extracapsular) • Muscle trismus. • Disuse muscle atrophy, contractures secondary to intra-articular ankylosis or psychogenic trismus. • Post-radiotherapy and thermal scarring. • Post-traumatic scarring. • Oral submucous fibrosis. Mohammed Almuzian, University of Glasgow, 2013 27
  28. 28. • Infection or inflammation of the masticatory muscle • Anatomical like Eagle syndrome. Presentation of Ankylosis If developed at early age: • Ankylosis in children produces impaired mandibular growth with bilateral deformity in all dimensions. • This deformity is asymmetrical in unilateral cases with a straight small hemi-mandible on the ankylosed side, and a marked contralateral bowing deformity. • Retrognathia and retrogenia become more apparent with age. • This produces an occlusal cant down to the normal side. • In rare bilateral cases the mandible is short but symmetrical. • In all cases the inter-incisal opening can be up to 10 mm even with total bony fusion reflecting the bone elasticity within the masticatory system. Diagnosis of for ankylosed TMJ • History and clinical examination • Imaging techniques including: 1. OPG. 2. True lateral skull. 3. PA Mohammed Almuzian, University of Glasgow, 2013 28
  29. 29. 4. CT scan with 3D reconstruction. 5. Standard orthognathic photographic series. Treatment Choices Resection of the ankylosis should be carried out as early as possible to enable normal growth and avoid secondary deformity. There are many treatment strategies depending on the age of the patient the duration of the deformity and degree of secondary deformity. A. Ankylosis presenting in childhood or Ankylosis presenting during or post adolescence 1. Excision of the condyle 2. Insertion of an interpositional temporalis myofascial peninsular flap 3. Bilateral coronoidectomies (coronoidotomies) to free temporalis contractures 4. Costochondral growth centre to restore function and ramus growth with or without Distraction osteogenesis. NB: The anteroposterior deficiency and asymmetry in childhood is usually self-corrected with catch-up growth. B. Ankylosis presenting after the completion of facial growth. 1. Excision of the condyle 2. Insertion of an interpositional temporalis myofascial peninsular flap 3. Bilateral coronoidectomies (coronoidotomies) to free temporalis contractures Mohammed Almuzian, University of Glasgow, 2013 29
  30. 30. 4. Reconstruction of the condyle with or without distraction osteogenesis. 5. In addition to one of these: • Genioplasty • BSS or inverted L osteotomy. • The maxillary procedure can be done to correct secondary problems C. Very late ankylosis in adults with no interference with facial growth. Exactly as B but in addition to 7-day pre- and 2-month postoperative course of bisphosphonate, which is currently alendronic acid 10 mg a day in the morning to avoid the localised fibrodysplasia ossificans . Surgical Approach and preparation The preoperative preparation differs from the standard orthognathic workup in several respects. 1. The anaesthetist must be skilled in fibre optic intubation and tracheostomy or submental approach. 2. The temporal area must be shaved and cleaned before the patient is taken into theatre. Complications 1. Scar 2. Damage to the orbital and frontal branches of the facial nerve. 3. Frey’s syndrome 4. Damage to parotid salivary gland Mohammed Almuzian, University of Glasgow, 2013 30
  31. 31. 5. Limited opening due to • Inadequate bone removal • Failure to do a bilateral coronoidectomies. • Postoperative fibrodysplasia ossificans • Fusion of the graft with re-ankylosis 6. Failure of the costochondral graft to grow. 7. Excess growth of the graft 8. Pneumothorax. Mohammed Almuzian, University of Glasgow, 2013 31

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