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Case Reports
. 2017 Dec 27:11:670-678.
doi: 10.2174/1874210601711010670. eCollection 2017.

Bilateral Elongated Mandibular Coronoid Process and Restricted Mouth Opening: A Case Report

Thomas Starch-Jensen  1 , Annette Dalgaard Kjellerup  1
Affiliations
Case Reports

Bilateral Elongated Mandibular Coronoid Process and Restricted Mouth Opening: A Case Report

Thomas Starch-Jensen et al. Open Dent J. .

Abstract

Introduction: Mandibular coronoid process hyperplasia is an uncommon congenital or developmental temporomandibular joint disorder, characterized by elongation of the coronoid process, which may cause limited mandibular movement as a consequence of interference between the hyperplastic coronoid process and the medial surface of the zygomatic arch.

Methods: Mandibular coronoid process hyperplasia commonly affects males in the second decade of life and the exact aetiology and pathogenesis is unknown. The condition can be uni- or bilateral. Progressive painless reduction in mouth opening is the main clinical finding and computed tomography is the most reliable imaging modality for confirming the diagnosis.

Results: Surgical intervention involving coronoidectomy and long-term intensive postoperative physiotherapy is the treatment of choice for mandibular coronoid process hyperplasia with impingement on the zygomatic bone and limited mouth opening. However, surgically induced fibrosis and the tendency for mandibular coronoid process regrowth may cause relapse and renewed limited mouth opening. Vigorous physical therapy should therefore be initiated shortly after surgery.

Conclusion: The purpose of this case report is to present the clinical and radiographic features of elongated mandibular coronoid process in an 18-year-old male with limited mouth opening, and to discuss the various surgical treatment modalities.

Keywords: Dentistry; Diagnostic imaging; Facial bones; General surgery; Hyperplasia; Temporomandibular joint.

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Figures

Fig. (1)
Fig. (1)
Preoperative maximal interincisal opening of 22 mm.
Fig. (2)
Fig. (2)
Preoperative orthopantomogram showing the elongated mandibular coronoid process projecting into the infratemporal fossa.
Fig. (3)
Fig. (3)
Preoperative Cone Beam Computed Tomography scan. (A) Coronal image showing close approximation of the right coronoid process to the medial surface of the zygomatic bone. (B) Coronal image showing close approximation of the left coronoid process to the medial surface of the zygomatic bone (C) Sagittal image showing enlargement of the right coronoid process impinged on the zygomatic bone.
Fig. (4)
Fig. (4)
Intraoperative clinical photo. (A) The elongated mandibular coronoid process exposed by an intraoral approach. (B) A low coronoidectomy performed with reciprocating saw.
Fig. (5)
Fig. (5)
Intraoperative clinical photo. (A) The mandibular coronoid processes after coronoidectomy. (B) The resected coronoid processes. (C) Frontal image of the resected coronoid processes.
Fig. (6)
Fig. (6)
The interincisal mouth opening increased to 42 mm in the operation room.
Fig. (7)
Fig. (7)
Postoperative orthopantomogram demonstrating successful removal of the coronoid processes.
Fig. (8)
Fig. (8)
Postoperative Cone Beam Computed Tomography scan. (A) Coronal image showing no interference between the coronoid processes and the medial surface of the zygomatic bone and arch. (B) Sagittal image showing the resected coronoid process with no interference with the zygomatic bone.
Fig. (9)
Fig. (9)
Three months postoperative maximal interincisal opening of 32 mm.
See this image and copyright information in PMC

References

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