Brief Clinical Studies
The Journal of Craniofacial Surgery
& Volume 25, Number 3, May 2014
Unilateral Condylar Hyperplasia: A Treatment Strategy Sabrina Ferreira, DDS, Andre´ Luis da Silva Fabris, DDS, Gabriel Ramalho Ferreira, DDS, MS, Leonardo Perez Faverani, DDS, PhD, Giovanna Barbosa Francisconi, DDS, Francisley A´vila Souza, DDS, PhD, Idelmo Rangel Garcia, Jr, DDS, PhD Abstract: Condylar hyperplasia (CH) is a pathologic condition that causes overdevelopment of the condylar head and neck as well as the mandible. Slowly progressive unilateral enlargement of the head and the neck of the condyle causes crossbite malocclusion, facial asymmetry, and shifting of the midpoint of the chin to the unaffected side. The etiology and the pathogenesis of CH remain uncertain. The diagnosis is made by clinical and radiologic examinations and bone scintigraph. A difference in uptake of 10% or more between condyles is regarded as indicative of CH, and the affected condyles had a relative uptake of 55% or more. When the diagnosis of active CH is established, the treatment consists of removal of the growth center by a partial condylectomy. The authors present the case of a 46-year-old male patient with right active type II CH or hemimandibular hyperplasia who underwent a high condylectomy. Key Words: Condylar hyperplasia, hemimandibular hypertrophy, facial asymmetry
C
ondylar hyperplasia (CH) is a pathologic condition that causes overdevelopment, unilaterally or bilaterally, of the condylar head and neck as well as the mandible.1 Slowly progressive unilateral enlargement of the head and the neck of the condyle causes crossbite malocclusion, facial asymmetry, and shifting of the midpoint of the chin to the unaffected side.2 For some researchers, the abnormal growth of the condyle is caused by an increased number of capillaries at its superoposterior portion: this is known as the ‘‘local circulatory theory.’’3 However, others hold that the etiologic factors responsible are fractures; inflammation of the temporomandibular joint (TMJ), particularly at the middle ear; or osteomyelitis of the ramus.3 Asymmetric conditions attributed to CH of the mandible were first reported by Adams in 1836. Condylar hyperplasias can present a range of phenotypes including hemimandibular hyperplasia (HH), hemimandibular elongation (HE), and hybrid forms.4 It normally occurs in mid teenage years, with increasing deformity until cessation of growth. Extraorally, many patients report problems related to From the Division of Oral and Maxillofacial Surgery and Traumatology, Department of Surgery and General Clinic, Ara0atuba Dental School, Univ Estadual Paulista Ju´lio de Mesquita FilhoYUNESP, Sao Paulo, Brazil. Received October 22, 2013. Accepted for publication November 13, 2013. Address correspondence and reprint requests to Sabrina Ferreira, DDS, Department of Surgery and General Clinic, Ara0atuba Dental School, Univ Estadual Paulista Ju´lio de Mesquita FilhoYUNESP, Rua Jose Bonifa´cio, 1193 Vila Mendon0a, CEP: 16015-050, Ara0atuba, SP, Brazil; E-mail: [email protected] The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000554
e256
FIGURE 1. A to E, Extraoral and intraoral clinical images before surgery.
the TMJ on the nonaffected side including popping, dislocation, pain, noises, and decreased opening.3 The diagnosis is usually made by clinical and radiologic examinations and bone scintigraph.2 Histologically, the presence of an uninterrupted layer of undifferentiated germinating mesenchymal cells, hypertrophic cartilage, and islands of chondrocytes in the subchondral trabecular bone were also said to be typical.5 When the diagnosis of active CH is established, the treatment of these patients consists of removal of the growth center by a partial condylectomy to stop the growth of the abnormal condyle and prevent worsening.1 The authors present the case of a 46-year-old male patient with right active type II CH or HH who underwent a high condylectomy.
CLINICAL REPORT A 46-year-old healthy man presented to the Department of Oral and Maxillofacial Surgery and Traumatology of the Dental School of Ara0atubaYFOA-UNESP complaining of discomfort on opening and closing his mouth, with a 5-year history of evolution. There was no history of trauma or inflammation in the jaw, and his surgical and family histories were insignificant. On clinical examination, he presented with slight vertical elongation of the right side of the face and downward sloping of the lip commissure. The occlusal plane was canted to the right, with the dental midline deviated to the affected side. The patient did not have an open bite. The findings from the clinical examination of both TMJs were normal (Figs. 1AYE). Image examination revealed enlargement of the right condyle with downward displacement of the gonial angle combined with an elongation of the right mandibular ramus (Figs. 2A, B, 3AYD). Technetium-99m methylene diphosphate bone scintigram showed
FIGURE 2. A, Initial panoramic radiograph; B, radiography for analysis of the mandibular condyle.
The Journal of Craniofacial Surgery
& Volume 25, Number 3, May 2014
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 3, May 2014
Brief Clinical Studies
FIGURE 3. A to D, Computed tomography showing large change in size of the right mandibular condyle.
increased uptake at the right condyle compared with the normal side. The relative uptake was 58%, and the condyle was regarded as active (Fig. 4). The diagnosis of active right type II CH (vertical pattern) was confirmed. On the basis of clinical and radiologic criteria, high condylectomy was performed under general anesthesia. Access was in the pretragus area, and after revealing the zygomatic arch and the joint capsule, the latter was incised, laying bare and resecting the extremity of the condyle. Condylar shaving was also performed. A lesion height of 18 mm was excised, and the articular disk was repositioned (Figs. 5A, B). The surgically excised tissue was sent for histologic examination. The tissue was characterized by a proliferation zone that exhibited a patchy distribution in such a sense that broad, cell-rich parts alternated with cell-poor areas or areas without any proliferation layer. In these latter areas, the fibrous layer that covered the condylar surface directly rested on the cartilage that, in these condyles, was not of the hyaline growth type but of the fibrocartilage type with dispersed chondrocytes. This fibrocartilage was not resorbed away, but instead of being bordered by a resorption zone, it rested on a continuous subchondral bony plate in which only remnants of a resorption zone were present, a diagnosis compatible with the type II described by Slootweg and Mu¨ller.5 The patient was placed on a soft diet, and the postoperative period was uneventful. Minimal changes in dental occlusion were noted by the patient, but this did not affect his jaw function or ability to chew. No signs of relapse were noticed 1 year after surgery, as confirmed by several clinical and radiologic evaluations (Figs. 6AYC, 7AYC).
DISCUSSION Condylar hyperplasia is a rare disease that modifies the anatomy of the condylus and the mandible. Condylar hyperplasia is also referred to as condylar hyperactivity and is one of several causes of facial asymmetry.6 Although this disorder is self-limiting, while it remains active, the asymmetry progresses together with the associated occlusal changes. The age of the patient determines the clinical appearance of the disease, influencing the growth speed.7 The etiology and the pathogenesis of CH remain uncertain. It is not known what triggers a condyle to suddenly start growing and become hyperplastic. Some patients present as first symptoms pain
FIGURE 4. A, Bone scintigram showing increased uptake at the right condyle compared with the normal side.
FIGURE 5. A and B, Tissue removed for condylar remodeling.
and joint noise as a result of functional pathology; secondary symptoms are impediment in opening of the mouth, sometimes associated with wobbling of the occlusion plane. Furthermore, palpating the hypertrophic condyles can be very painful. In simple cases, mandibular movement is limited.8 Two abnormal growth patterns are classically described, and each has clinical and radiologic characteristics: type I CH, also called horizontal pattern, rotational pattern, or HE, and type II CH, also called vertical pattern or HH. A combination of the 2 types is also possible.4,9,10 Chen et al11 suggested that the term condylar hyperplasia should not be used to refer to either HH or HE but should be applied before mandibular deformity occurs because progression of CH to HH or to HE, although difficult to prove, was possible.3 Type II, or vertical pattern, CH is characterized by an enlargement of not only the condyle but also the vertical ramus and the body of the mandible. In advanced stages, this causes a bowing of the inferior body of the mandible and an increased distance between the root tips and the mandibular canal. An open bite may be observed on the affected side unless there is occlusal compensation by the maxilla, causing canting of the occlusal plane. Type II CH may be difficult to differentiate from other osseous pathologies of the condyle, such as an osteochondroma, unless the condyle has an unusual shape.1,4,9,10 With regard to preferential laterality, an equal side distribution has been found by some authors, whereas others have found that the left side is more frequently affected.7,12 Nitzan et al2 found that this preferential laterality was highly sex dependent, with the right side predominating in female patients and the left side predominating in male patients. The diagnosis of CH may be made by a combination of clinical and radiologic findings. The first step in managing patients with CH is assessing condylar growth activity. This can be done using many methods. Determining whether the patient has active or latent
FIGURE 6. A to C, Extraoral and intraoral clinical images after surgery.
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
e257
Brief Clinical Studies
The Journal of Craniofacial Surgery
disease is essential before performing corrective surgery because choosing the correct procedure can decrease recurrence rates and the need for secondary surgery.6 Diagnosis of active CH is easily made with the use of modern imaging techniques.13 Clinical assessment can be supplemented with bone scintigraphy to show areas of increased osteoblastic activity using the bone-seeking radiopharmaceutical agent.13 Bone scanning with technetium-99m pyrophosphate or technetium-99m methylene diphosphonate has been advocated to detect active growth in the condyle.1 A difference in uptake of 10% or more between condyles is regarded as indicative of CH, and the affected condyles had a relative uptake of 55% or more.13 The value of computed tomographic images and three-dimensional reconstruction in the diagnosis of CH and the resulting mandibular asymmetry has been emphasized in the literature. The exact location and the degree of the deformity can be detected clearly.13 Treatment is primarily surgical, with or without orthodontics, and depends on the degree of severity and the status of condylar growth. The treatment plan is established according to the degree of asymmetry, the resulting malocclusion, and the condylar growth activity. If the asymmetry is diagnosed early, and it can be determined that the patient has an ongoing problem, early condylectomy and redirection of growth with functional appliance therapy and orthodontics can address the problem.14 Wolford et al10 propose orthognathic surgery and simultaneous high condylectomy to correct the asymmetry. Studies demonstrate that the high condylectomy with removal of the top 3 to 5 mm of the condylar head in the treatment of patients with active CH arrests the abnormal growth and provides highly predictable long-term outcomes.1 The high condylectomy arrests the excessive and disproportionate growth of the mandible by surgically removing one of the important mandibular growth sites and the site responsible for the CH pathologic growth process.10 A normal condyle is approximately 15 to 20 mm in mediolateral dimension and 8- to 10-mm wide anteroposteriorly.1 Not only the macromorphology but also the micromorphology of the diseased condyle differs from that on the unaffected side. The abnormal condyle appears larger or elongated, depending on the type. The hyperplastic portion of the condyle may be well demarcated and take the appearance of bone marrow, similar to a growth plate. However, in most cases, aside from the modified macroscopic anatomy of the condylar head, the pathologic portion is difficult to identify, making bone resection arbitrary.15 When normal and hypertrophic mandibular condyles are compared, the thickness of cartilaginous layer seems to be considerably increased in CH. Slootweg and Mu¨ller5 described 4 histologically different types of mandibular CH. They proposed a classification based on histologic criteria and divided hyperplastic condyles into 4 types depending on the arrangement and morphology of the various layers of the condyle (fibrous articular layer, undifferentiated mesenchyme proliferative layer, transitional layer, and hypertrophic cartilage layer; Table 1).
FIGURE 7. A to C, Imaging studies showing the condylar structure after the procedure high condylectomy.
e258
& Volume 25, Number 3, May 2014
TABLE 1. Histologic Classification of CH Classification Type I
Type II
Type III
Type IV
Characteristics Broad proliferation zone Underlying thick layer of hyaline growth cartilage Bone containing numerous cartilage islands Patchy distribution (cell-rich areas alternating with nonproliferative, cell-poor zones) Cartilage islands in cancellous bone are less frequent than in type I Great distortion Irregularly shaped masses of hyaline cartilage extending into cancellous bone of condylar neck or encroaching upward onto superficial articular layer Continuous subchondral bone plate covered by cell-poor fibrocartilaginous layer No proliferation layer of hyaline growth cartilage Burned-out appearance of condyle
In this case, clinical, radiologic, and histopathologic characteristics are compatible with CH. Minimal changes in dental occlusion were noted by the patient, but this did not affect his jaw function or ability to chew. No signs of relapse were noticed 1 year after surgery, as confirmed by several clinical and radiologic evaluations, showing satisfactory results with this treatment strategy.
REFERENCES 1. Wolford LM, Morales-Ryan CA, Garcia-Morales P, et al. Surgical management of mandibular condylar hyperplasia type 1. Proc (Bayl Univ Med Cent) 2009;22:321Y329 2. Nitzan DW, Katsnelson A, Bermanis I, et al. The clinical characteristics of condylar hyperplasia: experience with 61 patients. J Oral Maxillofac Surg 2008;66:312Y318 3. Angiero F, Farronato G, Benedicenti S, et al. Mandibular condylar hyperplasia: clinical, histopathological, and treatment considerations. Cranio 2009;27:24Y32 4. Obwegeser HL, Makek MS. Hemimandibular hyperplasiaVhemimandibular elongation. J Maxillofac Surg 1986;14:183Y208 5. Slootweg PJ, Mu¨ller H. Condylar hyperplasia. A clinico-pathological analysis of 22 cases. J Maxillofac Surg 1986;14:209Y214 6. Chepla KJ, Cachecho C, Hans MG, et al. Use of intraoral miniplates to control postoperative occlusion after high condylectomy for the treatment of condylar hyperplasia. J Craniofac Surg 2012;23:406Y409 7. Villanueva-Alcojol L, Monje F, Gonzalez-Garcia R. Hyperplasia of the mandibular condyle: clinical, histopathologic, and treatment considerations in a series of 36 patients. J Oral Maxillofac Surg 2011;69:447Y455 8. Cervelli V, Bottini DJ, Arpino A, et al. Hypercondylia: problems in diagnosis and therapeutic indications. J Craniofac Surg 2008;19:406Y410 9. Kaban LB. Mandibular asymmetry and the fourth dimension. J Craniofac Surg 2009;20:622Y631 10. Wolford LM, Mehra P, Reiche-Fischel O, et al. Efficacy of high condylectomy for management of condylar hyperplasia. Am J Orthod Dentofacial Orthop 2002;121:136Y150; discussion 50-1 11. Chen YR, Bendor-Samuel RL, Huang CS. Hemimandibular hyperplasia. Plast Reconstr Surg 1996;97:730Y737 12. Iannetti G, Cascone P, Belli E, et al. Condylar hyperplasia: cephalometric study, treatment planning, and surgical correction (our experience). Oral Surg Oral Med Oral Pathol 1989;68:673Y681 13. Alyamani A, Abuzinada S. Management of patients with condylar hyperplasia: a diverse experience with 18 patients. Ann Maxillofac Surg 2012;2:17Y23 14. Jones RH, Tier GA. Correction of facial asymmetry as a result of unilateral condylar hyperplasia. J Oral Maxillofac Surg 2012;70:1413Y1425 15. Bouchard C, Paris M, Villemaire JM. Intraoperative use of a gamma probe for the treatment of condylar hyperplasia: description of a new technique. J Oral Maxillofac Surg 2013;71:1099Y1106
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 3, May 2014
Unilateral Condylar Hyperplasia: A Treatment Strategy Sabrina Ferreira, DDS, Andre´ Luis da Silva Fabris, DDS, Gabriel Ramalho Ferreira, DDS, MS, Leonardo Perez Faverani, DDS, PhD, Giovanna Barbosa Francisconi, DDS, Francisley A´vila Souza, DDS, PhD, Idelmo Rangel Garcia, Jr, DDS, PhD Abstract: Condylar hyperplasia (CH) is a pathologic condition that causes overdevelopment of the condylar head and neck as well as the mandible. Slowly progressive unilateral enlargement of the head and the neck of the condyle causes crossbite malocclusion, facial asymmetry, and shifting of the midpoint of the chin to the unaffected side. The etiology and the pathogenesis of CH remain uncertain. The diagnosis is made by clinical and radiologic examinations and bone scintigraph. A difference in uptake of 10% or more between condyles is regarded as indicative of CH, and the affected condyles had a relative uptake of 55% or more. When the diagnosis of active CH is established, the treatment consists of removal of the growth center by a partial condylectomy. The authors present the case of a 46-year-old male patient with right active type II CH or hemimandibular hyperplasia who underwent a high condylectomy. Key Words: Condylar hyperplasia, hemimandibular hypertrophy, facial asymmetry
C
ondylar hyperplasia (CH) is a pathologic condition that causes overdevelopment, unilaterally or bilaterally, of the condylar head and neck as well as the mandible.1 Slowly progressive unilateral enlargement of the head and the neck of the condyle causes crossbite malocclusion, facial asymmetry, and shifting of the midpoint of the chin to the unaffected side.2 For some researchers, the abnormal growth of the condyle is caused by an increased number of capillaries at its superoposterior portion: this is known as the ‘‘local circulatory theory.’’3 However, others hold that the etiologic factors responsible are fractures; inflammation of the temporomandibular joint (TMJ), particularly at the middle ear; or osteomyelitis of the ramus.3 Asymmetric conditions attributed to CH of the mandible were first reported by Adams in 1836. Condylar hyperplasias can present a range of phenotypes including hemimandibular hyperplasia (HH), hemimandibular elongation (HE), and hybrid forms.4 It normally occurs in mid teenage years, with increasing deformity until cessation of growth. Extraorally, many patients report problems related to From the Division of Oral and Maxillofacial Surgery and Traumatology, Department of Surgery and General Clinic, Ara0atuba Dental School, Univ Estadual Paulista Ju´lio de Mesquita FilhoYUNESP, Sao Paulo, Brazil. Received October 22, 2013. Accepted for publication November 13, 2013. Address correspondence and reprint requests to Sabrina Ferreira, DDS, Department of Surgery and General Clinic, Ara0atuba Dental School, Univ Estadual Paulista Ju´lio de Mesquita FilhoYUNESP, Rua Jose Bonifa´cio, 1193 Vila Mendon0a, CEP: 16015-050, Ara0atuba, SP, Brazil; E-mail: [email protected] The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000554
e256
FIGURE 1. A to E, Extraoral and intraoral clinical images before surgery.
the TMJ on the nonaffected side including popping, dislocation, pain, noises, and decreased opening.3 The diagnosis is usually made by clinical and radiologic examinations and bone scintigraph.2 Histologically, the presence of an uninterrupted layer of undifferentiated germinating mesenchymal cells, hypertrophic cartilage, and islands of chondrocytes in the subchondral trabecular bone were also said to be typical.5 When the diagnosis of active CH is established, the treatment of these patients consists of removal of the growth center by a partial condylectomy to stop the growth of the abnormal condyle and prevent worsening.1 The authors present the case of a 46-year-old male patient with right active type II CH or HH who underwent a high condylectomy.
CLINICAL REPORT A 46-year-old healthy man presented to the Department of Oral and Maxillofacial Surgery and Traumatology of the Dental School of Ara0atubaYFOA-UNESP complaining of discomfort on opening and closing his mouth, with a 5-year history of evolution. There was no history of trauma or inflammation in the jaw, and his surgical and family histories were insignificant. On clinical examination, he presented with slight vertical elongation of the right side of the face and downward sloping of the lip commissure. The occlusal plane was canted to the right, with the dental midline deviated to the affected side. The patient did not have an open bite. The findings from the clinical examination of both TMJs were normal (Figs. 1AYE). Image examination revealed enlargement of the right condyle with downward displacement of the gonial angle combined with an elongation of the right mandibular ramus (Figs. 2A, B, 3AYD). Technetium-99m methylene diphosphate bone scintigram showed
FIGURE 2. A, Initial panoramic radiograph; B, radiography for analysis of the mandibular condyle.
The Journal of Craniofacial Surgery
& Volume 25, Number 3, May 2014
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 3, May 2014
Brief Clinical Studies
FIGURE 3. A to D, Computed tomography showing large change in size of the right mandibular condyle.
increased uptake at the right condyle compared with the normal side. The relative uptake was 58%, and the condyle was regarded as active (Fig. 4). The diagnosis of active right type II CH (vertical pattern) was confirmed. On the basis of clinical and radiologic criteria, high condylectomy was performed under general anesthesia. Access was in the pretragus area, and after revealing the zygomatic arch and the joint capsule, the latter was incised, laying bare and resecting the extremity of the condyle. Condylar shaving was also performed. A lesion height of 18 mm was excised, and the articular disk was repositioned (Figs. 5A, B). The surgically excised tissue was sent for histologic examination. The tissue was characterized by a proliferation zone that exhibited a patchy distribution in such a sense that broad, cell-rich parts alternated with cell-poor areas or areas without any proliferation layer. In these latter areas, the fibrous layer that covered the condylar surface directly rested on the cartilage that, in these condyles, was not of the hyaline growth type but of the fibrocartilage type with dispersed chondrocytes. This fibrocartilage was not resorbed away, but instead of being bordered by a resorption zone, it rested on a continuous subchondral bony plate in which only remnants of a resorption zone were present, a diagnosis compatible with the type II described by Slootweg and Mu¨ller.5 The patient was placed on a soft diet, and the postoperative period was uneventful. Minimal changes in dental occlusion were noted by the patient, but this did not affect his jaw function or ability to chew. No signs of relapse were noticed 1 year after surgery, as confirmed by several clinical and radiologic evaluations (Figs. 6AYC, 7AYC).
DISCUSSION Condylar hyperplasia is a rare disease that modifies the anatomy of the condylus and the mandible. Condylar hyperplasia is also referred to as condylar hyperactivity and is one of several causes of facial asymmetry.6 Although this disorder is self-limiting, while it remains active, the asymmetry progresses together with the associated occlusal changes. The age of the patient determines the clinical appearance of the disease, influencing the growth speed.7 The etiology and the pathogenesis of CH remain uncertain. It is not known what triggers a condyle to suddenly start growing and become hyperplastic. Some patients present as first symptoms pain
FIGURE 4. A, Bone scintigram showing increased uptake at the right condyle compared with the normal side.
FIGURE 5. A and B, Tissue removed for condylar remodeling.
and joint noise as a result of functional pathology; secondary symptoms are impediment in opening of the mouth, sometimes associated with wobbling of the occlusion plane. Furthermore, palpating the hypertrophic condyles can be very painful. In simple cases, mandibular movement is limited.8 Two abnormal growth patterns are classically described, and each has clinical and radiologic characteristics: type I CH, also called horizontal pattern, rotational pattern, or HE, and type II CH, also called vertical pattern or HH. A combination of the 2 types is also possible.4,9,10 Chen et al11 suggested that the term condylar hyperplasia should not be used to refer to either HH or HE but should be applied before mandibular deformity occurs because progression of CH to HH or to HE, although difficult to prove, was possible.3 Type II, or vertical pattern, CH is characterized by an enlargement of not only the condyle but also the vertical ramus and the body of the mandible. In advanced stages, this causes a bowing of the inferior body of the mandible and an increased distance between the root tips and the mandibular canal. An open bite may be observed on the affected side unless there is occlusal compensation by the maxilla, causing canting of the occlusal plane. Type II CH may be difficult to differentiate from other osseous pathologies of the condyle, such as an osteochondroma, unless the condyle has an unusual shape.1,4,9,10 With regard to preferential laterality, an equal side distribution has been found by some authors, whereas others have found that the left side is more frequently affected.7,12 Nitzan et al2 found that this preferential laterality was highly sex dependent, with the right side predominating in female patients and the left side predominating in male patients. The diagnosis of CH may be made by a combination of clinical and radiologic findings. The first step in managing patients with CH is assessing condylar growth activity. This can be done using many methods. Determining whether the patient has active or latent
FIGURE 6. A to C, Extraoral and intraoral clinical images after surgery.
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
e257
Brief Clinical Studies
The Journal of Craniofacial Surgery
disease is essential before performing corrective surgery because choosing the correct procedure can decrease recurrence rates and the need for secondary surgery.6 Diagnosis of active CH is easily made with the use of modern imaging techniques.13 Clinical assessment can be supplemented with bone scintigraphy to show areas of increased osteoblastic activity using the bone-seeking radiopharmaceutical agent.13 Bone scanning with technetium-99m pyrophosphate or technetium-99m methylene diphosphonate has been advocated to detect active growth in the condyle.1 A difference in uptake of 10% or more between condyles is regarded as indicative of CH, and the affected condyles had a relative uptake of 55% or more.13 The value of computed tomographic images and three-dimensional reconstruction in the diagnosis of CH and the resulting mandibular asymmetry has been emphasized in the literature. The exact location and the degree of the deformity can be detected clearly.13 Treatment is primarily surgical, with or without orthodontics, and depends on the degree of severity and the status of condylar growth. The treatment plan is established according to the degree of asymmetry, the resulting malocclusion, and the condylar growth activity. If the asymmetry is diagnosed early, and it can be determined that the patient has an ongoing problem, early condylectomy and redirection of growth with functional appliance therapy and orthodontics can address the problem.14 Wolford et al10 propose orthognathic surgery and simultaneous high condylectomy to correct the asymmetry. Studies demonstrate that the high condylectomy with removal of the top 3 to 5 mm of the condylar head in the treatment of patients with active CH arrests the abnormal growth and provides highly predictable long-term outcomes.1 The high condylectomy arrests the excessive and disproportionate growth of the mandible by surgically removing one of the important mandibular growth sites and the site responsible for the CH pathologic growth process.10 A normal condyle is approximately 15 to 20 mm in mediolateral dimension and 8- to 10-mm wide anteroposteriorly.1 Not only the macromorphology but also the micromorphology of the diseased condyle differs from that on the unaffected side. The abnormal condyle appears larger or elongated, depending on the type. The hyperplastic portion of the condyle may be well demarcated and take the appearance of bone marrow, similar to a growth plate. However, in most cases, aside from the modified macroscopic anatomy of the condylar head, the pathologic portion is difficult to identify, making bone resection arbitrary.15 When normal and hypertrophic mandibular condyles are compared, the thickness of cartilaginous layer seems to be considerably increased in CH. Slootweg and Mu¨ller5 described 4 histologically different types of mandibular CH. They proposed a classification based on histologic criteria and divided hyperplastic condyles into 4 types depending on the arrangement and morphology of the various layers of the condyle (fibrous articular layer, undifferentiated mesenchyme proliferative layer, transitional layer, and hypertrophic cartilage layer; Table 1).
FIGURE 7. A to C, Imaging studies showing the condylar structure after the procedure high condylectomy.
e258
& Volume 25, Number 3, May 2014
TABLE 1. Histologic Classification of CH Classification Type I
Type II
Type III
Type IV
Characteristics Broad proliferation zone Underlying thick layer of hyaline growth cartilage Bone containing numerous cartilage islands Patchy distribution (cell-rich areas alternating with nonproliferative, cell-poor zones) Cartilage islands in cancellous bone are less frequent than in type I Great distortion Irregularly shaped masses of hyaline cartilage extending into cancellous bone of condylar neck or encroaching upward onto superficial articular layer Continuous subchondral bone plate covered by cell-poor fibrocartilaginous layer No proliferation layer of hyaline growth cartilage Burned-out appearance of condyle
In this case, clinical, radiologic, and histopathologic characteristics are compatible with CH. Minimal changes in dental occlusion were noted by the patient, but this did not affect his jaw function or ability to chew. No signs of relapse were noticed 1 year after surgery, as confirmed by several clinical and radiologic evaluations, showing satisfactory results with this treatment strategy.
REFERENCES 1. Wolford LM, Morales-Ryan CA, Garcia-Morales P, et al. Surgical management of mandibular condylar hyperplasia type 1. Proc (Bayl Univ Med Cent) 2009;22:321Y329 2. Nitzan DW, Katsnelson A, Bermanis I, et al. The clinical characteristics of condylar hyperplasia: experience with 61 patients. J Oral Maxillofac Surg 2008;66:312Y318 3. Angiero F, Farronato G, Benedicenti S, et al. Mandibular condylar hyperplasia: clinical, histopathological, and treatment considerations. Cranio 2009;27:24Y32 4. Obwegeser HL, Makek MS. Hemimandibular hyperplasiaVhemimandibular elongation. J Maxillofac Surg 1986;14:183Y208 5. Slootweg PJ, Mu¨ller H. Condylar hyperplasia. A clinico-pathological analysis of 22 cases. J Maxillofac Surg 1986;14:209Y214 6. Chepla KJ, Cachecho C, Hans MG, et al. Use of intraoral miniplates to control postoperative occlusion after high condylectomy for the treatment of condylar hyperplasia. J Craniofac Surg 2012;23:406Y409 7. Villanueva-Alcojol L, Monje F, Gonzalez-Garcia R. Hyperplasia of the mandibular condyle: clinical, histopathologic, and treatment considerations in a series of 36 patients. J Oral Maxillofac Surg 2011;69:447Y455 8. Cervelli V, Bottini DJ, Arpino A, et al. Hypercondylia: problems in diagnosis and therapeutic indications. J Craniofac Surg 2008;19:406Y410 9. Kaban LB. Mandibular asymmetry and the fourth dimension. J Craniofac Surg 2009;20:622Y631 10. Wolford LM, Mehra P, Reiche-Fischel O, et al. Efficacy of high condylectomy for management of condylar hyperplasia. Am J Orthod Dentofacial Orthop 2002;121:136Y150; discussion 50-1 11. Chen YR, Bendor-Samuel RL, Huang CS. Hemimandibular hyperplasia. Plast Reconstr Surg 1996;97:730Y737 12. Iannetti G, Cascone P, Belli E, et al. Condylar hyperplasia: cephalometric study, treatment planning, and surgical correction (our experience). Oral Surg Oral Med Oral Pathol 1989;68:673Y681 13. Alyamani A, Abuzinada S. Management of patients with condylar hyperplasia: a diverse experience with 18 patients. Ann Maxillofac Surg 2012;2:17Y23 14. Jones RH, Tier GA. Correction of facial asymmetry as a result of unilateral condylar hyperplasia. J Oral Maxillofac Surg 2012;70:1413Y1425 15. Bouchard C, Paris M, Villemaire JM. Intraoperative use of a gamma probe for the treatment of condylar hyperplasia: description of a new technique. J Oral Maxillofac Surg 2013;71:1099Y1106
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
