TMJ ankylosis is among the most challenging conditions managed by maxillofacial surgeons, particularly in children, due to impaired mastication, speech, airway issues, and growth disturbances.[1,2] Kaban’s protocol (1990; refined 2009 with distraction osteogenesis) remains widely adopted.[3] A persistent point of debate, however, is the optimal sequencing of coronoidectomy relative to arthrectomy. Traditionally, arthrectomy precedes ipsilateral or bilateral coronoidectomy. Once the ankylotic mass is removed, mandibular mobility may make coronoid osteotomy technically demanding, prolong operative time, and reduce control of the surgical field.[4] Forceful mouth opening at that stage can also precipitate reflex bradycardia—an important anaesthetic concern.[5] We present a refined, reproducible technique in which ipsilateral coronoidectomy precedes arthrectomy, with Levandoski’s panographic analysis used preoperatively to standardize patient selection. This approach improves stability, safety, and efficiency while remaining simple to adopt.

A multi-centric study was conducted for analysis of outcomes of a refined surgical technique in temporomandibular joint ankylosis, in the department of Oral & Maxillofacial Surgery and Dentistry at three tertiary care hospitals. We included a total of 21 consecutive patients (aged 8–22 years) which were randomly selected with mean intraoperative inter-incisal opening of 11mm. All the bilateral temporomandibular joint ankylosis, medically compromised patients, and patients unwilling or unable to comply with the follow-up protocol were excluded. We focused on presenting, assessment and validating a coronoidectomy-first refinement of Kaban’s protocol, supported by Levandoski’s panographic analysis for preoperative case selection. Our Surgical Technique All the patients were operated under general anaesthesia and an Alkayat–Bramley incision is used. Layered dissection was utilised for exposure of the zygomatic arch, ankylotic mass, and coronoid process. (Figure 1) The steps of procedure is as follows: Step 1: Coronoidectomy (ipsilateral): The coronoid process is isolated. Osteotomy cuts are marked with a surgical bur and completed with osteotomes. (Figure 2) Step 2: Ankylotic mass resection: The maxillary artery is protected medially with a retractor. The ankylotic bone is resected using burs and osteotomes. (Figure 3) Step 3: Assessment: Inter-incisal opening is measured intraoperatively using a standard surgical measuring scale. If opening remains inadequate, a contralateral coronoidectomy is performed intraorally. (Figure 4)

Exposure of the ankylotic mass and coronoid process of the mandible, along with the zygomatic arch. (B) Coronoidectomy is performed prior to release of the ankylotic mass. (C) Ankylotic mass release. The application and analysis of the outcomes of our technical refinement on randomly selected 21 consecutive patients (15 males, 5 females; age 8–22 years) where all the patients operated had unilateral bony ankylosis, was obtained in the form of simple measurements and calculations. Preoperative inter-incisal opening: 0–7 mm (mean 3 mm) • Intraoperative inter-incisal opening post-release: 32–40 mm (mean 36 mm) • Operative time: ~18% reduction compared with our institutional experience using conventional sequencing • Complications: None observed (no reflex bradycardia, vascular injury, or nerve injury) • Follow-up: 12–14 months; all maintained >30 mm mouth opening; no recurrence These results suggest the sequence improves control and efficiency without compromising safety. Table 1. Comparison of Kaban’s protocol, earlier modifications, and present refinement Author/Year Modification Limitation Present Refinement Advantage Kaban (1990, 2009)¹,³ Arthrectomy first; coronoidectomy after Instability post-resection; resistance during opening; anesthetic concerns Stable platform for osteotomy; less resistance; smoother anesthesia Uppal (2010)8 Suggested coronoidectomy-first concept Limited standardization; minimal validation Adds objective radiographic selection + case series Andrade (2012)⁴ Protocol to reduce reankylosis in triad patients Greater complexity; subgroup-specific Simple, generalizable step order; compatible with adjuncts Baliga (2021)¹⁰ Re-appraisal of Kaban’s protocol No unified alternative Structured resequencing with diagnostic support and outcomes Present (2025) Coronoidectomy-first + Levandoski analysis — Stable, safe, reproducible; >1-year follow-up data

Why coronoidectomy-first? Performing coronoidectomy at the outset preserves mandibular stability, enabling precise osteotomy while the mandible remains supported by the ankylotic block. This reduces technical difficulty and operative time. Resistance encountered during forced opening after arthrectomy is also reduced, mitigating the risk of reflex bradycardia.[5] Levandoski’s panographic analysis: Levandoski (1992) described a panoramic radiographic method to quantify coronoid process hyperplasia by comparing the condylion–coronoid distance with the condylion–gonion distance; a ratio >1.15 suggests hyperplasia.[6, 7] This analysis is low-cost, widely available, and reproducible. Integrating it into preoperative planning helps standardize case selection for coronoidectomy, grounding the refinement in radiographic evidence rather than surgeon preference alone. In our study cases, Levandoski’s analysis supported decision-making and anticipated the need for contralateral release when indicated. Positioning relative to prior literature: Earlier works have questioned the universality of Kaban’s sequence [3, 10] and some have suggested alternative steps or emphasized measures to prevent reankylosis.[4, 8, 9] What distinguishes the present refinement is: 1. Systematic resequencing (coronoidectomy-first) to maintain stability; 2. Diagnostic integration (Levandoski’s analysis) for objective selection; and 3. Clinical validation with >1-year follow-up demonstrating durable function. The technique is especially attractive in pediatric and resource-limited settings where shorter anesthesia time, fewer hemodynamic perturbations, and straightforward execution are valuable. It is compatible with interpositional arthroplasty or distraction strategies when indicated.

A coronoidectomy-first sequence, supported by Levandoski’s panographic analysis, enhances stability, reduces intraoperative resistance and anesthetic risk, and shortens operative time—without compromising outcomes. This practical, reproducible refinement advances the field toward standardized, evidence-informed TMJ ankylosis management. Multicenter validation is warranted.

1. Kaban LB, Perrott DH, Fisher K. A protocol for management of temporomandibular joint ankylosis. J Oral Maxillofac Surg. 1990;48:1145-51. 2. Perrott DH, Kaban LB. Temporomandibular joint ankylosis in children. Oral Maxillofac Clin North Am. 1994;6:187-202. 3. Kaban LB, Bouchard C, Troulis MJ. Management of pediatric TMJ ankylosis. J Oral Maxillofac Surg. 2009;67:1966-78. 4. Andrade NN, Kalra R, Shetye SP. New protocol to prevent TMJ reankylosis and potentially life-threatening complications in triad patients. Int J Oral Maxillofac Surg. 2012;41:1495-500. 5. Loewinger J, Cohen M, Levi E. Bradycardia during elevation of a zygomatic arch fracture. J Oral Maxillofac Surg. 1987;45(8):710-1. 6. Levandoski GE. Panoramic radiography in the evaluation of coronoid process hyperplasia. J Oral Maxillofac Surg. 1992;50(5):479-84. 7. Kubota Y, Takenoshita Y, Takamori K, Kanamoto M, Shirasuna K. Levandoski panographic analysis in the diagnosis of hyperplasia of the coronoid process. Br J Oral Maxillofac Surg. 1999;37:409-11. 8. Uppal N, Baliga M, Ramanathan A. Is a modification of Kaban's protocol in treating temporomandibular joint ankylosis appropriate? J Oral Maxillofac Surg. 2010;68(3):706-7. 9. Tompach PC, Dodson TB, Kaban LB. Autogenous temporomandibular joint replacement. In: Fonseca RJ, Bays RA, Quinn PD, editors. Oral and Maxillofacial Surgery. Vol. 4. Philadelphia: Saunders; 2009. p. 301-15. 10. Baliga M, Mishra A. Is Kaban's protocol justified in the present scenario? J Oral Maxillofac Surg. 2021;79(1):6.