Osteochondromas rarely affect the mandibular condyle. An unusual case of an osteochondroma occurring in the left mandibular condyle in a 40-year-old man who presented with mandibular deviation and malocclusion is reported; this represents the 37th documented case in the English-language literature. The tumor was resected through condylectomy. Four-year follow-up assessments revealed satisfactory function and occlusion, without evidence of recurrence of the tumor.

Introduction

Osteochondroma is an exophytic lesion that arises from the cortex of bone and is capped with cartilage.1 It is frequently found in the general skeleton but is rare in the condylar region of the mandible.2 The tumor is most often located at the medial surface.3 The pathogenesis of osteochondroma is still controversial, and differentiation between osteoma, osteochondroma, and hypertrophy, as described by Thoma,4 may be difficult at times. The most common clinical symptoms are malocclusion, with unilateral posterior open bite on the affected side and a crossbite on the contralateral side, and progressive facial asymmetry.5

There have been only 36 reported cases of osteochondroma of the mandibular condyle in the English-language literature2,3,5-34 (Table I). This tumor was diagnosed for 16 male subjects and 20 female subjects, with a mean age of 40.5 years and an age range of 19 to 69 years, according to previously reported cases. The literature revealed a female preponderance for osteochondroma of the mandibular condyle of 55.55%.

Surgical treatment of an osteochondroma of the mandibular condyle has been condylectomy, although in several cases excision of only the lesion was performed.2,6,7,9,26,28,32,34 The surgical approach has been preauricular; however, submandibular and intraoral approaches, as well as combined approaches, have been used.8

Although the risk of recurrence is a disadvantage when only excision of the tumor is performed, there is only one recurrence of a condylar osteochondroma reported in the literature, which occurred 1 year after its excision in multiple pieces.32 In this case, a patient with an osteochondroma arising in the left mandibular condyle is discussed. A review of the clinical and pathologic features of the previously reported cases of osteochondroma occurring in the condylar process is also presented.

Case Report

A 40-year-old man was referred to the Department of Oral and Maxillofacial Surgery, Gülhane Military Medical Academy (Ankara, Turkey), with complaints of progressive facial asymmetry, difficulty with speech and mastication secondary to mandibular hypomobility, and limited mouth opening. The patient reported having had mandibular trauma in a motor vehicle accident 8 years previously, which resulted in facial asymmetry. More recently, the patient had experienced difficulty in opening his mouth.

The patient's general condition was unremarkable. Clinical examination showed facial asymmetry, with mandibular deviation to the right. The mandibular dental midline was deviated 8 mm to the right of the maxillary dental midline, reflecting asymmetric prognathism. Interincisal mouth opening at the initial examination was 31 mm. A crossbite was present on the contralateral side. Lateral mandibular movements were restricted. Localized joint pain was noted with palpation. No lymph nodes were palpable.

A panoramic radiograph showed a well-defined, bone-like, radiopaque mass in association with the left condylar head (Fig. 1). The axial and coronal computed tomographic (CT) scans revealed an opaque mass, which was located around the mandibular condyle (Figs. 2 and 3). Three-dimensional CT imaging of the patient showed a large mass in the anteromedial region of the left condyle (Fig. 4). The radiographic examination suggested a slowly growing, calcifying tumor, probably of cartilaginous nature, eroding the condylar head.

The tumor was excised under general anesthesia. The upper and lower compartments of the temporomandibular joint were accessed through an auriculotemporal approach. The surgical field was expanded with retraction along the masseter muscle downward. The disc, which adhered to the lesion at the anterior aspect of the condyle, was resected. There was no evidence of ankylosis. The tumor was resected en bloc. The lesion could be easily separated from the surrounding tissues. Reshaping of the resection borders was performed to enable improved function. The condylar position and the occlusion were retained with positional maxillomandibular fixation for 2 weeks, followed by functional physiotherapy for 3 weeks. The postoperative course was uneventful. Active range-of-motion exercises, including vertical jaw opening, lateral excursions, and protrusion, were performed four to six times per day.

The excised mass was spheroidal, measuring 22 × 30 × 32 mm (Fig. 5). Its slightly irregular surface was covered with soft tissue. Histopathologic examinations were performed after decalcification and hematoxylin and eosin staining of the specimens.

Histologically, it was noted that the nodular mass was covered with a proliferative cap of cartilage with underlying zones of cancellous bone and irregular calcified cartilage. The osteocytes and chondrocytes were individually housed in a lacuna with a single nucleus (Fig. 6). On the basis of the histopathologic features, a diagnosis of osteochondroma was made.

Four-year follow-up assessments revealed satisfactory function and occlusion, with an interincisal mouth opening of 38 mm. There was no evidence of recurrence.

Discussion

Osteochondroma is a relatively common finding in the skeleton,19,23 occurring frequently in the metaphyseal region of long bones. It is also found in the ribs, scapulae, clavicles, and vertebrae, as well as the mandible.21 Although this process rarely affects the jaw, cases have been reported to involve the mandibular condyle, coronoid process, symphysis. posterior maxilla, maxillary sinus, and zygomatic arch. The most revealing features are slowly changing occlusion, progressive facial asymmetry, and limited and often painful mandibular movements.9

The pathogenesis of osteochondroma has been the subject of much debate. The most commonly accepted view is a metaplastic change of the periosteum and/or the osteochondral layer in the condyle, leading to production of cartilage, which subsequently ossifies.9

The cause of osteochondroma is unclear, but trauma has been considered as a possible factor.8,10-12 The patient in our case report noted that his facial asymmetry was the result of a motor vehicle accident.

The differential diagnosis of benign neoplasms known to involve the mandibular condyle includes osteoma, osteoblastoma, chondroma, chondroblastoma, and osteochondroma.8 Osteomas are benign tumors that consist primarily of mature, compact, cancellous bone. Osteomas occurring in the condylar process can be classified into two types according to their pattern of proliferation, i.e., those that proliferate and cause replacement of the condyle by the osteoma37-41 and those that form a pedunculated or osseous mass on the condyle or neck of the mandible.42-46 Thoma4 reported that osteomas of the condyle are tabulated; in contrast, hyperplasia results in enlargement of the condyle, which retains its original shape. However, it is frequently impossible to distinguish these entities histologically.

Osteoblastoma is a rare tumor of the maxillofacial region, with the average age of occurrence being 16.5 years. The patient presents with pain and swelling. The lesion consists of a loose, sparsely collagenous, richly vascular stroma containing small, spindled, uniform cells.47

Chondromas consist of well-defined lobules of mature hyaline cartilage that may contain areas of calcification. The tendency for chondrogenic tumors to be malignant requires numerous fields to be examined to ensure sufficient evidence for a diagnosis.48,49

Chondroblastomas sometimes occur in the cranial bones and in the mandibular condyle. They consist of a proliferation of immature cartilage cells, with focal production of a variably differentiated cartilaginous matrix. The absence of malignant-appearing chondrocytes and variable numbers of benign multinucleated cells differentiate chondroblastoma from chondrosarcoma.50

Osteochondroma is a benign lesion that is presumed to arise in the long bones from herniation of cartilage through the epiphyseal plate in the formative years. It is significant in the maxillofacial region mainly when it occurs around the condyle or the coronoid process. Radiographically, the lesion is easily differentiated from chondroma because it is most frequently an extraneous appendage, rather than a rarefaction within the normal jaw confines, and is more radiopaque, which represents its true ossification.

Histologically, osteochondroma needs to be distinguished from osteoma, benign osteoblastoma, chondroma, and chondroblastoma. The histologic criteria for the diagnosis of an osteochondroma include the presence of clusters of chondrocytes in the cartilaginous cap, arranged in parallel, oblong, lacunar spaces, similar to those of normal epiphyseal cartilage.8

In most reported cases of osteochondroma, treatment has consisted of subcondylar resection of the mass.10-25 After tumor removal with condylectomy, an open bite can develop from loss of ramal height and condylar position. This sometimes requires intermaxillary fixation for a 3- to 4-week period, retraining of the masticatory musculature, and prolonged physical therapy. Some authors think that condylar reconstruction is needed to avoid occlusal problems and to normalize mandibular function.29,33 Reconstruction of the condyle could be performed through several different methods, such as a condyle with or without a glenoid prosthesis. Metal prostheses have proven to be biocompatible and functional but have increased costs. Another alternative involves a free autogenous bone graft, i.e., iliac crest graft,28 costochondral graft,5,8,30,31 sternoclavicular joint graft,33,36 or local osseous pedicle graft.29 It was preferred to remove the tumor through condylectomy in this case. Postoperative exercises should be begun as soon as possible. Early mobilization is one of the most important factors to prevent the potential recurrence of fibrous adhesions. In this case, the patient was encouraged to start postoperative exercises after positional maxillomandibular fixation. The patient's postoperative course was uneventful. Four years postoperatively, the occlusion was found to be stable and the maximal interincisal opening was 38 mm.

References

1. Schajowicz F, Ackerman LV, Sissons HA, et al: International Histological Classification of Tumors, No. 6: Histological Typing of Bone Tumors. Geneva, Switzerland, World Health Organisation, 1972.

2. Iizuka T, Schroth G, Laeng RH, Lädrach K: Osleochondroma of the mandibular condyle: report of a case. J Oral Maxillofac Surg 1996; 54: 495-501.

3. Kurita K, Ogi N, Echiverre NV, Yoshida K: Osteochondroma of the mandibular condyle: a case report. Int J Oral Maxillofac Surg 1999; 28: 380-2.

4. Thoma KH: Tumors of the condyle and temporomandibular joint. Oral Surg 1954; 7: 1091.

5. Gaines RE, Lee MB, Crocker DJ: Osteochondroma of the mandibular condyle; case report and review of the literature. J Oral Maxillofac Surg 1992; 50: 899.

6. Eller DJ, Blakemore JR, Stein M, et al: Transoral resection of a condylar osteochondroma: report of a case. J Oral Surg 1977; 35: 409.

7. Wang-Norderud R, Ragab RR: Osteocartilaginous exostosis of the mandibular condyle. Scand J Plast Reconstr Surg 1975; 9: 165.

8. Henry CH, Granite EL, Rafetto LK: Osteochondroma of the mandibular condyle: report of a case and review of the literature. J Oral Maxillofac Surg 1992; 50: 1102-8.

9. Koole R, Steenks MH, Witkamp TD, Slootweg PJ, Shaefer J: Osteochondroma of the mandibular condyle: a case report. Int J Oral Maxillofac Surg 1996; 25: 203-5.

10. Melarkey DW, Roffinella JP, Kaplan H: Osteocartilagenous exostosis (Osteochondroma) of the mandibular condyle. J Oral Surg 1966; 24: 271.

11. Thompson HC, Stalker FD, Schriver WR: Osteochondroma of the mandibular condyle: report of a case. J Oral Surg 1969; 27: 53.

12. Koehl GL, Tilson HB: Osteochondromas associated with facial asymmetry and masticatory dysfunction: report of two cases. J Oral Surg 1977; 35: 934.

13. Kanthak FF, Harkins HN: Unilateral hypertrophy of the mandibular condyle associated with chondroma. Surgery 1938; 4: 898.

14. Curtin JW, Greeley PW: Osteochondroma of the mandibular condyle. Plast Reconstr Surg 1959; 24: 511.

15. Schultz LW, Vazirani SJ, Bolden TE: Unilateral hyperplasia and exostosis of the mandibular condyle: a clinical syndrome. Oral Surg 1960; 13: 387.

16. Ramon Y, Lerner MA, Leventen G: Osteochondroma of the mandibular condyle: report of a case. Oral Surg 1964; 17: 16.

17. Grossman E: An unusual case of clicking jaw. Br J Oral Surg 1965; 3: 159.

18. Hayward JR, Megquier RJ: Surgical technic for removal of a large Osteochondroma of the mandibular condyle. J Oral Surg 1968; 26: 752-7.

19. Keen RR, Callahan GR: Osteochondroma of the mandibular condyle: report of a case. J Oral Surg 1977; 35: 140.

20. Simon GT, Kendrick RW, Whitlock RH: Osteochondroma of the mandibular condyle: case report and its management. Oral Surg 1977; 43: 18.

21. Sanders B, McKelvy B: Osteochondromatous exostosis of the condyle. J Am Dent Assoc 1977; 95: 1151.

22. Johnson G, Zweig BE, Iykin AB: Osteochondroma of the mandibular condyle: report of a case. J N J Dent Assoc 1981; 52: 17-20.

23. Kaneda T, Torii S, Yamashita T, Inoue N, Shimizu K: Giant Osteochondroma of the mandibular condyle. J Oral Maxillofac Surg 1982; 40: 818.

24. Mizuno A, Nakamura T, Motegi K, Shirasawa H: Osteochondroma of the mandibular condyle: report of a case and review of the Japanese literature. Int J Oral Surg 1983; 12: 221.

25. Marks RB, Carlton DM, Carr RF: Osteochondroma of the mandibular condyle: report of a case with 10 year follow up. Oral Surg 1984; 58: 30.

26. Strickland RD, Hirsch SA, Goldberg JS: Osteochondroma of the mandibular condyle. Cranio 1985; 3: 189-92.

27. Forssell H, Happonen RP, Forssell K, Virolainen E: Osteochondroma of the mandibular condyle: report of a case and review of the literature. Br J Oral Maxillofac Surg 1985; 23: 183.

28. Schweber SJ, Frensilli JA: Osteochondroma of the mandibular condyle: report of a case and review of the literature. J Am Dent Assoc 1986; 113: 269.

29. Loftus MJ, Bennet JA, Fantasia JE: Osteochondroma of the mandibular condyles: report of three cases and review of the literature. Oral Surg 1986; 61: 221.

30. Herbosa EG, Rotskoff KS: Condylar Osteochondroma manifesting as class III skeletal dysplasia: diagnosis and surgical approach. Am J Orthod Dentofacial Orthop 1991; 100: 472-9.

31. Goyal M, Sidhu SS: A massive Osteochondroma of the mandibular condyle. Br J Oral Maxillofac Surg 1992; 30: 66.

32. Vezeau 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.

33. Karras SC, Wolford LM, Cottrell DA: Concurrent Osteochondroma of the mandibular condyle and ipsilateral cranial base resulting in temporomandibular ankylosis: report of a case and review of the literature. J Oral Maxillofac Surg 1996; 54: 640.

34. Aydin MA, Küçükçelebi A, Sayilkan S, Çelebioglu S: Osteochondroma of the mandibular condyle: report of two cases treated with conservative surgery. J Oral Maxillofac Surg 2001; 59: 1082.

35. Luhr HG, Busch W: Diagnosis and therapy of tumors and pseudotumors of the temporomandibular joint [in German]. Dtsch Zahnarztl Z 1973; 28: 505-13.

36. Wolford LM, Cottrell DA, Henry CH: Sternoclavicular grafts for TMJ reconstructions. J Oral Maxillofac Surg 1994; 52: 119.

37. Lucas RB: Pathology of Tumours of the Oral Tissues, Ed 4, p 191. Edinburgh, Scotland, Chuchill Livingstone, 1984.

38. Kaplan I, Calderon S, Bushner AA: Peripheral osteoma of the mandible: a study of 10 cases and analysis of literature. J Oral Maxillofac Surg 1994; 52: 467-70.

39. Schneider LC, Dolinsky HB, Grodjesk JE: Solitary peripheral osteoma of the jaws; report of case and review of literature. J Oral Surg 1980; 38: 452-5.

40. Miles AEW: The use of the biopsy drill and punch in the diagnosis of oral lesions. Br Dent J 1951; 91: 7.

41. Kragh LV: Bone tumors of the jaws. In: Thomas Oral Pathology, Ed 6. p 560. Edited by Gorlin RJ, Goldman HM. St Louis, MO, Mosby, 1970.

42. Ivy RH: Benign bony enlargement of the condyloid process of the mandible. Ann Surg 1927; 85: 27.

43. Nelson DF, Gross BD, Miller FE: Osteoma of the mandibular condyle: report of case. J Oral Surg 1972; 30: 761-3.

44. MacLennan WD, Brown RD: Osteoma of the mandible. Br J Oral Surg 1974; 12: 219-24.

45. Nwoku AL, Koch H: The temporomandibular joint: a rare location for bone tumours. J Maxillofac Surg 1974; 2: 113-9.

46. Thoma KH: Tumors of the mandibular joint. J Oral Surg 1964; 22: 157.

47. Henry CH, Granite EL, Rafetto LK: Osteochondroma of the mandibular condyle: report of the case and review of the literature. J Oral Maxillofac Surg 1982; 50: 1102-8.

48. Dahlin DC, Unni KK: Bone Tumors: General Aspects and Data on 8542 cases, Ed 4, p 18-32. Springfield, IL, Charles C Thomas, 1986.

49. Chaudhry AP, Robinovitch MR, Mitchell DF, et al: Chondrogenic tumors of the jaws. Am J Surg 1961; 102: 403.

50. Spahr J, Elzay RP, Kay S, et al: Chondroblastoma of the temporomandibular joint arising from articular cartilage: a previously unreported presentation on an uncommon neoplasm. Oral Surg Oral Med Oral Pathol 1982; 54: 430-5.

Guarantor: Hakan Alpay Karasu, DDS PhD

Contributors: Hakan Alpay Karasu, DDS PhD*; Col Kerim Ortakoglu[dagger]; Com Kemal Murat Okcu[dagger]; Col Omer Gunhan[double dagger]

* Department of Oral and Maxillofacial Surgery, Ankara University Faculty of Dentistry, Besevler. Ankara. Turkey.

[dagger] Department of Oral and Maxillofacial Surgery, Gulhane Military Medical Academy, 06018, Etlik, Ankara, Turkey.

[double dagger] Department of Pathology, Gulhane Military Medical Academy, 06018, Etlik, Ankara, Turkey.

This manuscript was received for review in March 2004. The revised manuscript was accepted for publication in August 2004.

Return to Osteochondroma

Home

Contact

Resources

Exchange Links

ebay