Journal of Indian Academy of Oral Medicine and Radiology

: 2017  |  Volume : 29  |  Issue : 1  |  Page : 56--59

Osteochondroma involving mandibular condyle

Latika Bachani, Ashok Lingappa, Shivaprasad Shankaramurthy, Sujatha Gulagadar Parameshwarappa 
 Department of Oral Medicine and Radiology, Bapuji Dental College and Hospital, Davangere, Karnataka, India

Correspondence Address:
Latika Bachani
Department of Oral Medicine and Radiology, Bapuji Dental College and Hospital, Davangere  -  577  004, Karnataka


Osteochondroma is defined as an osteocartilagenous exostosis with cartilage capped exophytic lesion that arises from the bone cortex. It is a slow growing benign tumor that is rarely seen in the maxillofacial region. Osteochondroma of the mandibular condyle is a relatively rare condition that causes a progressive enlargement of the condyle, usually resulting in facial asymmetry, temporomandibular joint (TMJ) dysfunction and malocclusion. Radiographically, there is a unilaterally enlarged condyle usually with an exophytic growth of the tumor from the condylar head. The treatment of osteochondroma is primarily surgical resection of the tumor. This paper reports a case of osteochondroma of the right mandibular condyle presenting as a painless restricted mouth opening.

How to cite this article:
Bachani L, Lingappa A, Shankaramurthy S, Parameshwarappa SG. Osteochondroma involving mandibular condyle.J Indian Acad Oral Med Radiol 2017;29:56-59

How to cite this URL:
Bachani L, Lingappa A, Shankaramurthy S, Parameshwarappa SG. Osteochondroma involving mandibular condyle. J Indian Acad Oral Med Radiol [serial online] 2017 [cited 2022 May 18 ];29:56-59
Available from:

Full Text


Osteochondroma is a slow growing benign tumor of mature hyaline cartilage and bone that is rarely seen in the maxillofacial region.[1] It generally occurs at the end of the growth plates of long bones. When present in the maxillofacial region, the tumor most commonly affects the mandibular coronoid process or the mandibular condyle.[2] Pathogenesis and etiology of this tumor have not been well understood. When it is seen in the mandibular condyle, it mainly causes mandibular asymmetry, crossbite, posterior open bite, temporomandibular joint problems with pain, and limitation of mandibular lateral motions.[3] Radiographically, these lesions are radiopaque with distinct borders and easily identified on cone beam computed tomography (CBCT) as well as plain radiography.[2] Although CBCT scans have not been considered the best tool to evaluate noncalcified cartilage caps, they have a recognizably high accuracy to demonstrate calcified cartilage, and to delineate soft-tissue alterations secondary to tumor growth and atrophy of the masticatory muscles. Condylectomy with complete lesion removal is the most common treatment of condylar osteochondroma.

 Case Report

A 46-year-old male patient reported to our department complaining of reduced mouth opening since 4–5 months. It was insidious in onset, gradually progressing in severity and associated with moderate pain over the right preauricular region on jaw movements. He also noticed clicking sound over the right preauricular region on jaw movements. History of difficulty in mastication and vertigo was also revealed. The patient gave no history of trauma. He gave a positive history of recurrent right ear infection since 5 years, for which he had consulted an ENT specialist recently. He was treated with antibiotics for the same and was diagnosed with bilateral temporomandibular joint (TMJ) ankylosis few days back. Following this, he was referred to our department for further intervention.

On general physical examination, he was well oriented to time, place and person, and all the vitals were within the normal range. On extraoral examination, no gross facial asymmetry was noted. No swelling was noted in the right preauricular region. Bilateral submandibular lymph nodes were palpable. They were solitary, oval, approximately 1 cm in diameter, firm, mobile, and nontender. Maximum mouth opening was measured as 11 mm [Figure 1], and lateral and protrusive movements were also restricted. On TMJ examination, the right side condylar movements were not appreciable. There was clicking on the right side on early jaw opening with deviation of mandible towards the right side. On palpation, tenderness was elicited in the right side preauricular region. Muscles of mastication were nontender.{Figure 1}

On intraoral examination, full complement of permanent dentition was present except for missing 13, 18, 28, 38 and 48. Bilaterally, Angle’s class I molar relation was present with crowding in lower anteriors. The teeth 12, 21 and 31 presented with grade I mobility. On the basis of history and clinical features, a working diagnosis of a benign tumor involving the right condyle was made. The differential diagnoses listed were osteochondroma, osteoblastoma, and osteoma.

Further radiographs were taken for the patient, which included orthopantomogram (OPG), transpharyngeal TMJ view and CBCT of right TMJ. OPG [Figure 2] revealed a solitary pedunculated radiopacity attached on the superior surface of right condyle. It was roughly oval in shape, measuring approximately 1 cm in diameter. The borders were irregular and the internal structure appeared homogenously radiopaque. The joint space was reduced. The articular eminence appeared sclerotic. Transpharyngeal view of right TMJ closed mouth [Figure 3] revealed a pedunculated radiopaque lesion measuring approximately 1 cm attached on the anterior portion of the superior surface of the condyle. The borders appeared well-defined and internal structure was continuous with the condylar head. The joint space was reduced. The articular eminence appeared sclerotic.{Figure 2}{Figure 3}

CBCT of the right TMJ closed mouth [Figure 4] revealed abnormal shape of the condylar head. The superior portion of the condyle showed pedunculated radiopaque structure measuring approximately 20 mm in the mediolateral direction, 13 mm in the anteroposterior direction, and 10 mm in the superior-inferior direction. It was roughly knob-like and was surrounded by a thin corticated border. The anterior portion of the condyle exhibited a bony projection. The internal structure showed mild decrease in the density of trabeculation of the condyle. The HU of the condyle was 1200–1400 and that of the lesion was 600–800 HU. The overall joint space was reduced. The articular eminence and the inferior temporal bone appeared sclerotic.{Figure 4}

Management was done with excisional biopsy of the lesion with condylectomy via placement of right abdominal dermal fat graft under general anesthesia. The excised specimen was sent for histopathologic examination. The histopathologic picture [Figure 5]a and [Figure 5]b revealed sections from the condyle showing a cartilaginous cap with trabecular bone containing fat marrow. Sections from the bony outgrowth showed fibrocollagenous tissue overlying cartilaginous islands merging into bone trabeculae separated by fat marrow. All these features were suggestive of osteochondroma of the mandibular condyle. Patient is under follow-up. The postoperative OPG [Figure 6] after right condylectomy was taken. There was no change in occlusion post surgery. Patient is now on physiotherapy to improve his mouth opening. The mouth opening measured 1 month postoperatively was 20 mm [Figure 7].{Figure 5}{Figure 6}{Figure 7}


Osteochondroma, or osteocartilagenous exostosis, is a cartilage-capped exophytic lesion that arises from the cortex of bone. It constitutes 20–50% of all benign tumors and 10–15% of all bone tumors.[4] Osteochondroma of mandibular condyle is a rarity, which usually presents during the fourth decade of life, however, it has a wide age range of 11–69 years. The male-to-female ratio is 1:1.5.[5] It generally arises from the medial-anterior portion of the condyle and extends superiorly.[2] Our case was also consistent with the findings in literature in terms of age and site of occurence.

The pathogenesis of osteochondromas of the mandibular condyle is speculative. Trauma and inflammation have been implicated as either initiating or predisposing factors. The occurrence of these tumors in the condyle tends to support the theory of aberrant foci of epiphyseal cartilage on the surface of the bone.[6] One theory states that stress in the tendinous insertion region of lateral pterygoid muscle, where focal accumulations of cells with cartilaginous potential exist, leads to formation of these tumors. This may also explain the occurrence of the osteochondromas in the coronoid process stressed by the tension of temporalis muscle.[7] Other theories regarding the cause include neoplastic, developmental, reparative and traumatic etiologies.[8]

Early occurrence of the unilateral condylar hyperplasia results in gradual deviation of the midline away from the affected side with increased vertical mandibular growth. When growth of the lesion is slow, there is reciprocal compensatory vertical growth of the maxilla with canting of the occlusal plane to accommodate the increasing mandibular vertical dysplasia.[2] The condylar function of the affected side can be partially or totally lost and limited mouth opening may be observed. Other common clinical manifestations of the osteochondroma of the mandibular condyle include facial asymmetry, swelling at the TMJ region, disturbance of mouth opening, and joint pain.[9] In some cases, the mass in the condylar region may cause severe pain, hypomobility, clicking and locking of the TMJ, as well as headaches and cervical pain.[10] In our case, the patient presented with restricted mouth opening, tenderness with minimal condylar movements, and an opening click without any obvious swelling. Differential diagnoses of osteochondroma include osteoma, benign osteoblastoma, chondroma, and chodroblastoma.

Imaging techniques can be valuable tools for accurately diagnosing and determining treatment for a variety of diseases and are supportive to clinical examination. Orthopantomograph at best can be considered as a screening tool in the detection of these lesions. It presents as an enlarged sclerotic mass that can reach gigantic proportions. Osteochondromas are seen most often on the medial aspect of the mandibular condyle (52%), followed by an anterior location (20%), and rarely in the lateral or superior positions (1%).[5] On computed tomography (CT) scans, the tumor is seen as a bony outgrowth arising from the condylar neck. CT clearly depicts the continuation of the cortex and medulla of the parent bone with that of the tumor, a feature considered diagnostic of osteochondromas.[4] Although CT scans have not been considered the best tool to evaluate noncalcified cartilage caps, they have a recognizably high accuracy to demonstrate calcified cartilage, as well as to delineate soft-tissue alterations secondary to tumor growth and atrophy of the masticatory muscles for complementary surgical indications. Buoncristiani et al.[11] reported fatty degeneration of the ipsilateral lateral pterygoid muscle on magnetic resonance imaging (MRI) in a case of osteochondroma arising from the glenoid fossa. This was speculated to be a functional response of the muscle to aberrant mandibular position. There are no reports that discuss similar soft-tissue changes in the masticatory muscles on CT, and the identification of this sign on CT is a new and useful finding. Analysis of this finding helps in planning the rehabilitation of the masticatory functions following excision of the tumor. The three-dimensional reconstruction, which can be obtained with CT also helps the surgeon in preoperative planning.

Histologically, the osteochondroma has a layer of thickened, cellular periosteum, deep to which lies a sheet of proliferating chondrocytes. Under this cartilaginous cap is a zone of ossification resulting in the formation of cancellous bone.[12] According to Villanueva et al., the main goal of osteochondroma treatment, regardless of the lesion etiology, should be the achievement of acceptable mouth opening ranges. Surgical approach to the tempromandibular area is challenging. The preauricular approach is the most popular approach for the tempromandibular area. The surgical technique is controversial. It may be performed through either excision of the lesion or condylectomy followed by reconstruction for the preservation of mandible height.[13] In large tumors with infratemporal extension, hemicoronal flap and zygomatic arch osteotomy might be done for better access.[14] Though the risk of malignant transformation of osteochondroma is only 1% for solitary lesions, there has been no reported case of mandibular condyle osteochondroma that has converted to malignancy.[15]


Mandibular osteochondroma, though a rare entity, should be considered in the differential diagnosis of masses in the region of the TMJ. Panoramic radiographs at best can be considered as a screening modality in the detection of these lesions. Because of the distinctive radiographic appearance of mandibular osteochondroma, CT provides an invaluable tool to assist in evaluation and treatment planning. The recommended treatment of choice for symptomatic osteochondromas is surgical resection.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


1Utum ER, Pedron IG, Perrella A, Zambon CE, Ceccheti MM, Cavalcanti MGP. Osteochondroma of the tempromandibular joint: A case report. Braz Dent J 2010;21:253-8.
2Kumar VV, Ebenezer S, Lobbezoo F. Osteochondroma after mandibular dislocation. J Oral Maxillofac Surg 2011;69:309-13.
3Kurita K, Ogi N, Echiverre NV, Yoshida K. Osteochondroma of the mandibular condyle. A case report. Int J Oral Maxillofac Surg 1999;28:380-2.
4Murphey MD, Choi JJ, Kransdorf MJ, Fleming DJ, Gannon HF. Imaging of osteochondroma: Variants and complications with radiologic – Pathologic correlation. Radiographics 2000;20:1407-34.
5Peroz I, Scholman HJ, Hell B. Osteochondroma of the mandibular condyle: A case report. Int J Oral Maxillofac Surg 2002;31:455-6.
6Karras SC, Wolford LM, Cottrell DA. Concurrent osteochondroma of the mandibular condyle and ipsilateral cranial base resulting in temporomandibular joint ankylosis: Report of a case and review of the literature. J Oral Maxillofac Surg 1996;54:640-6.
7Wolford LM, Mehra P, Franco P. Use of conservative condylectomy for treatment of osteochondroma of the mandibular condyle. J Oral Maxillofac Surg 2002;60:262-8.
8Dahlin DC, Unni KK. Bone Tumors. General aspects and data on 8542 cases. 4th ed. Springfield (IL): Charles C. Thomas; 1986. p. 18-32.
9Ord RA, Warburton G, Caccanese JF. Osteochondroma of the condyle: Review of 8 cases. Int J Oral Maxillofac Surg 2010;39:523-8.
10Sanders B, McKelvy B. Osteochondromatous exostosis of the condyle. J Am Dent Assoc 1977;95:1151-3.
11Buoncristiani RD, Casagrande A, Felsenfeld AL. Osteochondroma of the glenoid fossa: Occurrence in an atypical location. J Oral Maxillofac Surg 2003;61:134-7.
12Marks RB, Carlton DM, Carr RF. Osteochondroma of the mandibular condyle: Report of a case with 10 year follow up. Oral Surg Oral Med Oral Pathol 1984;58:30-2.
13Vezeau PJ, Fridrich KL, Vincent SD. Osteochondroma of the mandibular condyle: Literature review and report of two atypical cases. J Oral Maxillofac Surg 1995;53:954-63.
14More CB, Gupta S. Osteochondroma of mandibular condyle: A clinic-radiographic correlation. J Natural Sci Biol Med 2013;4:465-8.
15Aydin MA, Kucukcelebi A, Sayilkan S, Celebioglu S. Osteochondroma of the mandibular condyle: Report of 2 cases treated with conservative surgery. J Oral Maxillofac Surg 2001;59:1082-9.