Treatment modalities of TMJ ankylosis: experience in Delta Nile, Egypt

Abstract

The study reports the authors’ experience in managing TMJ ankylosis in Delta Nile, Egypt (1995–2006) and compares the surgical modalities used. 101 patients (109 joints) were reviewed in this retrospective study. Pre- and postoperative assessment included history, radiological and physical examination, and mouth opening. Age, sex, aetiology, joint(s) affected, surgical modality, complications and follow up periods were evaluated. Various types (fibrous, fibro-osseous and bony) of TMJ ankylosis were diagnosed; trauma was the commonest aetiology. The patients’ age range was 2–41 years, 62% were female, and the follow up period ranged from 14 to 96 months. Average mouth opening was significantly increased from 5.3 mm pre-operatively to 32.9 mm 12 months postoperatively ( P = 0.0001). Marked improvement in mouth opening was documented when the ramus-joint complex was reconstructed using distraction osteogenesis (34.7 mm), costochondral graft (34.4 mm) and Surgibone (34.6 mm). Gap arthroplasty showed least satisfactory mouth opening compared with other techniques ( P = 0.001). Minor and major complications were encountered in 33% of cases, including 5% recurrence rate. Early release of TMJ ankylosis; reconstruction of the ramus height with distraction osteogenesis or bone grafting combined with interpositional arthroplasty, followed by vigorous physiotherapy is successful for managing TMJ ankylosis.

Temporomandibular joint ankylosis (TMJa) is a condition in which there is immobility of the joint; it is characterized by formation of an osseous, fibrous or fibro-osseous mass fused to the base of the skull. This mass is the pathology responsible for the ankylosis, but it is not a neoplastic process capable of continued growth . TMJa occurs primarily in the first and second decades of life (35–92%) and is commonly associated with trauma (13–100%), local or systemic infection (0–53%), systemic diseases such as ankylosing spondylitis, rheumatoid arthritis and psoriasis (28%); it also occurs after TMJ surgery . TMJa is associated with difficulties in speech, mastication, swallowing, yawning, poor oral hygiene, and it interferes with nutrition and dental treatment. There are also restricted airway problems and impeded eruption of mandibular molars. In growing patients, deformities of the mandible and maxilla may occur together with malocclusion . In classifying TMJa in children, S awhney identified four different types: in type 1 there is minimal bony fusion, but extensive fibrous adhesions around the joint; type 2 has more bony fusion especially at the outer edge of the articular surface, but no fusion within the more medial area of the joint; in type 3 there is a bridge of bone between the mandible and the temporal bone; and in type 4 the joint is replaced by a mass of bone.

Treatment for TMJa aims at restoring joint function, improving the patient’s aesthetic appearance and quality of life and preventing re-ankylosis . Owing to technical difficulties and a high incidence of recurrence, the treatment of TMJa and its complications poses a significant challenge to clinicians and patients. The methods, techniques and materials used for the reconstruction of the mandible after surgical excision of the ankylosed joint are debated . Surgical procedures for the treatment of the ankylosed condyle can be broadly classified into three groups: condylectomy, gap arthroplasty, and interpositional arthroplasty. Numerous materials have been used to reconstruct the TMJ including autogenous, alloplastic and xenogenic bovine bone grafts .

Joints reconstructed with alloplastic materials have experience infection and inflammatory problems as the immune system reacts to a foreign body . Autogenous interpositional materials, such as temporalis muscle, dermis–fat graft, auricular cartilage and buccal pad fat, have been used by several authors . Some authors have suggested using the remaining TMJ disc, after its repositioning . Several autologous bone grafts are used to reconstruct the ramus-joint complex, including costochondral and clavicular bone grafts . Resected elongated coronoid process and excised ankylotic mass have also been tried. Distraction osteogenesis has been used successfully before or after the release of the joint ankylosis, to correct secondary facial asymmetry.

The literature contains several studies about the management of TMJa, but many of them are isolated cases or small series reports. The aim of this study is to report the authors’ experience of managing over 100 patients with TMJa in Egypt, and to determine whether the different surgical modalities they have used from 1995 to 2006 differ in terms of outcomes and complications.

Patients and methods

This clinical retrospective study included 101 TMJa patients (109 joints), managed between 1995 and 2006. High standards of scientific research ethics were applied in carrying out all aspects of this study. For enrolment in this study, patients had to fulfil the following inclusion criteria: diagnosed with true TMJa involving the articulating surfaces ( Fig. 1 ); the pre- and postoperative data record, including patient consent, clinical and radiological examinations had to be available; a postoperative follow up period of at least 12 months had to have been completed. Data concerning age, sex, aetiology, joint(s) affected, treatment modalities and postoperative complications were evaluated. The pre-operative assessment included a detailed patient history, radiological and physical examination and mouth-opening measurements. A calliper was used to measure the degree of mouth opening five times: pre-, intra- and postoperatively (immediately and at 6 and 12 months) according to the following equation: mouth opening equals interincisal distance plus overbite. Radiological investigations for all patients included orthopantomography (OPG), posteroanterior skull view (PA) and some cephalometric views, computed tomography (CT), and bone scan in specific cases.

Fig. 1
Axial CT of a young woman showing a unilateral bony ankylosis (c) of the right TMJ as results of previous facial trauma.

The TMJ was surgically accessed via a standard preauricular approach with temporal extension ( Fig. 2 ). The superficial temporal fascia was identified, and its plane was followed inferiorly and anteriorly to reach the zygomatic arch. The periosteum over the zygomatic arch was incised and reflected, followed by vertical incision of the joint capsule. The ankylotic mass was exposed and excised. Tendons of the masseter and medial pterygoid muscles were carefully dissected and maximum mouth opening was tried intra-operatively. When a bone graft, such as a costochondral graft (CCG), was to be used and fixed with wires, a second incision was also made 2 cm below the angle of the mandible for insertion and fixation of the graft. With recent advances in rigid fixation, many cases were reconstructed with bone grafts, fixed with screws, through the preauricular approach only. An intraoral incision was employed in some cases to gain access to the contralateral coronoid processes for coronoidectomy, when it was indicated.

Fig. 2
Intra-operative photograph showing periauricular incision (black arrow) with temporal extension (white arrow).

Surgical burs and osteotomes were carefully employed to remove a segment of bony and/or fibrous tissue between the inferior border of the zygomatic arch and the superior edge of the vertical ramus to create a gap of 1.5–2 cm. Care was taken to protect the maxillary artery behind and deep to the osseous mass, and to remove any bony tissue deep and medial in the surgical field that might hinder free movement of the mandible and contribute to the recurrence of the ankylosis. Intra-operative arterial or venous bleeding was usually controlled with gauze packing.

Patients were categorized, according to the surgical technique employed, into 3 main groups: gap arthroplasty; interpositional arthroplasty and reconstruction arthroplasty.

In gap arthroplasty, a 1.5–2 cm gap was created after resection of the ankylosis mass and left without any interpositional material. Patients in this group (11%) were mainly adult, had minimal facial deformity and declined any type of bone grafting or interpositional materials.

In interpositional arthroplasty the temporomyofascial muscle flap (TMF) is used as a spacer. This technique was mainly used in adult patients who potentially had the risk of re-ankylosis, for example patients with recurring or large bony ankylosis.

Reconstruction arthroplasty was mainly used in growing patients and in adults who had marked facial asymmetry. It included one of the four following techniques. First, CCG with or without TMF ( Fig. 3 ), buccal pad fat (BPF) or retained original disc. This technique was mainly employed in growing patients (50%) and/or where the articulating disc could be preserved. Second, a Unilab Surgibone bar, which is a composite matrix of hydroxyapatite and collagen of bovine origin, with one compact smooth surface and a rough cancellous one (Unilab Surgibone, Inc., Mississauga, Ontario, Canada). This technique was mainly employed in adult patients (10%) diagnosed with severe discrepancy in ramus height, who declined a second procedure to harvest autologous bone graft ( Fig. 4 ). Third, an autologous coronoid process graft and TMF: was used in adult patients with elongated coronoid process (7%), and shorter ramus who requested the least invasive surgery ( Fig. 5 ). Fourth, intraoral distraction osteogenesis followed by TMF interpositional arthroplasty. The authors have only been using this technique recently and employed it in 11 (10%) patients who were mainly adolescent or adult ( Fig. 6 ).

Fig. 3
(a) Intra-operative photograph showing the 5th right rib while it was harvested (R); the harvested rib graft (CCG) has a short chondral portion (black arrow) and the osteochodoral junction is protected by the overlying periosteum. (b) Intra-operative photograph showing the temporalis myofascial flap (TMF) reflected over the zygomatic arch (Z), to serve as an interposition.

Fig. 4
(a) Coronal CT showing right TMJ ankylosis, as a result of previous condylar fracture, notice the medial and lateral calluses (black arrows), and the condylar remnant (C). (b) Postoperative coronal CT showing the Unilab Surgibone xenogenic graft (G) fixed with 2 screws (arrows) to the lateral surface of the ramus (R) and articulating with the temporal bone (Z).

Fig. 5
(a) Postoperative radiograph showing the coronoid process graft (G) fixed with bone plates and screws to the ramus stud and articulating with the temporal bone (Z). (b) Postoperative photograph showing satisfactory mouth opening after 12 months.

Fig. 6
(a) OPG showing left TMJ ankylosis before resection and short left vertical ramus and the distraction device is activated. (b) A 17-month postoperative OPG after consolidation of the bony callus and resection of the ankylosis, notice maturation of the distracted left ramus and erupting wisdom teeth. (c) 17-Month postoperative frontal view showing excellent mouth opening and functioning articulation.

Whenever the TMF was used as an interposition, a 3 cm long myofascial flap was turned outward and downward over the zygomatic arch and placed into the glenoid fossa and then sutured medially and posteriorly to the adjacent tissues with 3/0 Proline ( Fig. 3 b). In certain cases, buccal pad fat was dissected and employed as an interposition to avoid unsightly depression over the temporal area, particularly in bald patients. When a CCG was used, in unilateral cases, the graft was taken from the 5th or 6th rib through a submammary incision. In bilateral cases, both the 5th and the 7th ribs were employed. The length of the cartilaginous component of the CCG used ranged from 3 to <6 mm and its end was dome-shaped to represent the condylar head. This graft was secured to the outer posterior surface of the ascending ramus of the mandible with either two stainless-steel wire sutures or, as in recent cases, with 2 or 3 screws. As an alternative to CCG, the Unilab Surgibone bar was used in some adult TMJa patients who did not agree to have another incision for autogenous bone graft. In such cases, the graft was rigidly fixed to the ramus stud with titanium screws ( Fig. 4 b). When the coronoid process was either a part of the ankylosis or too long and mouth opening was still less than had been expected, ipsilateral coronoidectomy was performed through the same preauricular incision used for arthroplasty. Contralateral coronoidectomy was also considered (trans-oral) in cases where it was too long to impinge on the posterior surface of the contralateral maxilla. When the resected coronoid process was to be used for reconstruction of the vertical ramus and serve as a condyle, it was modified and fixed to the ramus stump using a 4-hole titanium plate ( Fig. 5 ).

To avoid complications accompanying bone grafting, intraoral distraction osteogenesis of the mandible has recently been used in some TMJa patients before releasing the joint ankylosis. In this modified technique, the ramus and the body of the mandible and the maxilla were distracted transorally and then after consolidation, the TMJa was treated using TMF interposition arthroplasty (details about this technique and the patient profiles are given in S adakah et al. ) ( Fig. 6 ).

In most patients, a vacuum drain was inserted for 48 h and all wounds were closed in layers and heavily dressed. Postoperative analgesics and prophylactic antibiotics were prescribed for all patients to control pain, enhance the opening of the mandible and reduce the possibility of infection. Patients were discharged 3–5 days postoperatively. All patients were trained to carry out mouth-opening exercises at home, which included encouraging them to move their mandibles vertically and horizontally by frequent chewing. The other daily exercise was the use of wooden tongue depressors (2 mm thick), bilaterally between the upper and lower premolar–molar region. The number of wooden spatulas was increased until the patient gained and retained the maximum mouth opening that had been achieved intra-operatively. Patients and/or parents were trained and encouraged to continue this exercise at home three times a day for 15 min each time. Professional physiotherapy was instituted a few days postoperatively and continued every other day until mouth opening was satisfactory. It included various forms of mouth opening and jaw exercises, massage and deep heat therapy. All patients were seen weekly for 6 weeks and then followed up clinically and radiologically at 3 and 6 months and then annually to the end of the follow up period. Minitab 13.1 statistical package was used to analyse the quantitative results obtained. Descriptive statistics was employed to calculate the mean, standard deviation, minimum and maximum values for different variables. The Anderson Darling normality test was used to test the data, which was found to be parametric. Accordingly, ANOVA followed by Fisher’s test was used to compare the degree of mouth opening before and after different surgical modalities in different patient groups.

Results

101 patients (62% female) who fulfilled the inclusion criteria and had had surgical repairs of ankylosed TMJ were included in this study. The mean age of this patient series at the time of surgery was 19.43 years (range 2–41 years) and the most frequent age group was 11–20 years. All patients were followed up for a period ranging from 14 to 96 (mean 28.9) months ( Table 1 ). Aetiologically, trauma was reported in 92 (84%) cases including 54 (50%) cases resulting from a fall, 18 (17%) cases were the result of car and cycling accidents and 20 (18%) cases were due to other traumatic incidents including kicks from animals, assault, birth trauma and others. Causes other than trauma were reported in the remaining 16 (16%) cases including previous TMJ surgery in 8 (7%), osteoarthritis in 2 (2%), hyperplasia and infection in 1 (1%) case each, in addition to another 5 (5%) cases from unknown causes ( Table 2 ). Unilateral TMJa was diagnosed in 93 (92%) patients, 53 (54%) of which were on the right side and 40 (40%) on the left side, while bilateral ankylosis was diagnosed in 8 (8%) patients. Three different types of ankylosis were identified: bony ankylosis in 77 (71%) patients; fibrous ankylosis in 6 (6%) and fibro-osseous ankylosis in 26 (24%) patients ( Table 3 ).

Table 1
Descriptive statistics for the patient’s age, gender, follow up period and mouth opening.
Mean age in years Mean mouth opening in mm
M (37.6%) F (62.4%) Total Follow up (months) Pre-op. Intra-op. Post-op.
Immediate 6 Months 12 Months
Mean 21.5 18.1 19.43 28.9 5.3 31.8 27.9 32.5 32.9
SD 9.7 7.4 8.5 13.9 3.7 4.17 4.3 3.6 3.3
Range 2–41 3–33 2–41 14–96 0–13 22–40 17–37 24–40 22–42
Key : M = male; F = female; Op. = operative; SD = standard deviation.

Table 2
Aetiology of TMJ ankylosis in 101 patients.
Aetiology of ankylosis Number of cases (%)
Trauma: 92 (84.4%)
Falls 54 (49.5%)
Cycling 9 (8.3%)
Car accident 9 (8.3%)
Animal kick 7 (6.4%)
Assault 5 (4.6%)
Birth trauma 2 (1.8%)
Others 6 (5.5%)
Previous TMJ surgery 8 (7.4%)
Osteoarthritis 2 (1.8%)
Infection 1 (0.9%)
Neoplastic (condylar chondroma) 1 (0.9%)
Unknown aetiology 5 (4.6%)
Total 109 joints in 101 patients

Table 3
Data analysis for 109 cases, including diagnosis, treatment modalities and results.
Variables Number of cases (%) Mouth opening
Mean (SD)/mm (1 year post-op.)
P -Value #
Gender: 0.380
1. Male 42 (38.5%) 33.3 (3.8)
2. Female 67 (61.5%) 32.7 (3.0)
Age groups 0.001
0–10 years 16 (14.7%) 31.9 (2.2)*
11–20 years 50 (45.7%) 33.8 (2.9)**
21–30 years 31 (28.6%) 31.6 (3.3)*
31–40 years 9 (8.2%) 35.4 (3.8)**
41–50 years 3 (2.8%) 31.0 (5.3)*
Side 0.162
1. Right: 53 (52.5%) 33.4 (3.4)
2. Left: 40 (39.6%) 32.2 (3.0)
3. Bilateral: 08 (07.9%) 33.4 (3.4)
Type of the ankylosis 0.564
Fibrous 06 (05.5%) 32.8 (2.1)
Fibro-osseous 26 (23.9%) 33.5 (2.7)
Bony 77 (70.6%) 32.7 (3.5)
Treatment modalities: 0.001
1. CCG only 20 (18.4%) 33.8 (3.2)**
3. CCG + TMF 14 (12.8%) 34.4 (2.6)**
4. CCG + BPF 09 (08.3%) 34.3 (1.9)**
2. CCG + retained disc 11 (10.1%) 30.6 (2.0)*
5. Surgibone 11 (10.1%) 34.6 (1.0)**
6. Gap + no interpose 11 (10.1%) 29.1 (3.4)*
7. Gap + TMF 14 (12.8%) 30.7 (3.1)*
8. Gap + TMF + distr. 11 (10.1%) 34.7 (1.9)**
9. Coronoid + TMF 08 (07.3%) 34.5 (3.2)**
Mouth opening 0.0001
Pre-operative 109 05.3 (3.7)*
Intra-operative 109 31.8 (4.2)***
Immediate post-op. 109 27.9 (4.3)**
6-Month post op. 109 32.5 (3.6)***
One year post op. 109 32.9 (3.3)***
Method of bone graft fixation 0.001
N/A (no bone graft) 36 (33.1%) 31.6 (3.8)*
Wiring 20 (18.3%) 31.4 (2.6)*
Screws 45 (41.3%) 34.6 (2.5)**
Bone plates and screws 08 (07.3%) 33.4 (1.0)**
Cartilage length of the CCG: 0.053
No CCG 43 (39.5%) 32 (3.8)
Long (3-6 mm): 28 (25.6%) 33.6 (2.5)
Short (<3 mm): 38 (34.9%) 33.5 (3.0)
Epsilateral coronoidectomy: 0.001
With 48 (44.0%) 34.2 (2.9)**
Without 61 (56.0%) 32.0 (3.3)*
Contralateral side 0.796
Coronoidectomy 09 (08.9%) 33.1 (3.5)
Both condylectomy and coronoidectomy 08 (07.9%) 33.1 (4.4)
Had no surgery 83 (82.2%) 32.3 (3.1)
Interpositional tissues 0.06
TMF 44 (40.3%) 33.1 (3.5)
BPF 09 (08.3%) 34.3 (1.9)
Retained disc 11 (10.1%) 30.6 (2.0)
Non 45 (41.3%) 33.1 (3.3)
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Feb 8, 2018 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Treatment modalities of TMJ ankylosis: experience in Delta Nile, Egypt

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