What Leads To Condylar Hyperplasia & How Is It Diagnosed and Treated?

Condylar hyperplasia is a rare disorder affecting the symmetry of the face. This article discusses about what leads to condylar hyperplasia and how it is diagnosed?

What Leads To Condylar Hyperplasia?

Normal growth of facial bones is characterized by a symmetrical face, a balanced dental occlusion, with the coordinated development of both the mandibular condyles. and is characterized by excessive growth of mandibular condylar cartilage (head and neck of the condyle), which is mostly present unilaterally, leading to facial asymmetry.1 Before discussing about what leads to condylar hyperplasia, it is important to know about the condition and its types.

Types of Condylar Hyperplasia

Condylar hyperplasia is of two types:

  1. Condylar Hyperplasia With Horizontal Growth: It is known as hemimandibular elongation which is characterized by deviation of chin towards the contralateral side, midline shift to the contralateral side, and posterior crossbite on the contralateral side. Histological findings suggest an excessive growth in the horizontal vector, an enlarged ramus, and a normal condyle.
  2. Condylar Hyperplasia With Vertical Growth: Also known as hemimandibular hyperplasia, vertical growth hyperplasia involves excessive growth in the vertical vector and the condylar head. It is characterized by sloping rima oris with minimal chin deviation, super-eruption of maxillary molars of the affected side, open site, and midline shift.

Both Horizontal And Vertical Growth: In this type, there is excessive growth in both sectors. The chin deviates towards the contralateral sides, there can be a possibility of an open bite, and slopping rima oris with possible chin deviation.

Causes of Condylar Hyperplasia

The causes of condylar hyperplasia are not clear but there are few theories which suggest the possible cause of the condition.

One theory states that it can be due to trauma which can lead to increase in the number of repair mechanism and hormones in the area leading to an increase in growth of the mandible of the affected side. Another theory states that an increase in the loading of the temporomandibular joint can lead to an increase in the expression of the bone forming molecules.

The other possible causes of condylar hyperplasia include a rare and benign tumor or any malignant condition originating in mandibular condyle.

Condylar hyperplasia is found affecting females more than males.

How Is Condylar Hyperplasia Diagnosed?

Clinical examination is the commonest way in which condylar hyperplasia is diagnosed. The doctor examines the chin and looks for any possibility of a tumor or a bone growth.
Other diagnostic techniques include a panoramic radiograph, nuclear imaging, and PA cephalometry.

The nuclear imaging techniques include single photon emission computed tomography, positron emission tomography (PET), and bone scintigraphy. X-ray, films the affected side and determines the increase in the volume of the head of the condyle, enlarged neck of the condyle, and the level of the ascending ramus. Bone scan is a functional imaging process. It helps to identify the area of increased osteoblastic metabolic activity. An isotope marker uptake confirms the active nature of condylar hyperplasia, which helps in determining the treatment plan. An MRI is performed to examine temporomandibular disorder. It does not provide any definite information where there is no dysfunction of the condylar meniscus.

These are some of the confirmed ways in which condylar hyperplasia is diagnosed.

Treatment of Condylar Hyperplasia

There are various treatment options for condylar hyperplasia.

Orthognathic surgery is performed when the active condylar growth stops. The main motive of waiting for the growth to stop is to lessen the chances of worsening of the facial asymmetry.

Condylectomy is another procedure which is done to remove the part of the growing condyle to arrest any active growth. In some cases, condylectomy is done along with articular disk repositioning and orthognathic surgery, to treat the patient with condylar hyperplasia.

Now that you are aware of what leads to condylar hyperplasia and how it is diagnosed, you can seek medical opinion for any such concerns and follow medical advice.

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