Cause and Prevalence of Condylar Hyperplasia
- Unknown cause of condylar hyperplasia
- Theories suggest trauma or increased loading of the temporomandibular joint
- Predominantly affects women (64% of patients)
- Estimated that about 30% of people with facial asymmetry have condylar hyperplasia
Diagnosis of Condylar Hyperplasia
- PA cephalometry, panoramic radiograph, and nuclear imaging used for diagnosis
- Nuclear imaging techniques such as SPECT, PET, and bone scintigraphy are commonly used
- SPECT imaging shows increased uptake on affected side
- A difference of at least 10% or a minimum ratio of 55% to 45% uptake indicates active condylar growth
- Diagnosis requires multiple data points
Classification of Condylar Hyperplasia
- Hugo Obwegeser and Makek classified condylar hyperplasia into three categories (Type 1 and Type 2)
- Type 1 develops characteristics from horizontal vector, Type 2 from vertical vector
- Type 1 occurs 15 times more commonly than Type 2
- Wolford et al. developed an updated classification in 2014
- Slootweg & Muller devised a histopathological classification for condylar tissues
Treatment Options for Condylar Hyperplasia
- Orthognathic surgery can be performed after active condylar growth has finished
- Surgery aims to minimize facial asymmetry
- Condylectomy involves removing part of the growing condyle to stop active growth
- Condylectomy can be done with articular disk repositioning and orthognathic surgery
- Treatment options depend on individual cases
References
- Olate, Sergio et al. (2013) - Review of diagnosis and treatment protocol
- Landesberg, R. et al. (1995) - Separation and characterization of cellular elements in the growth center
- Obwegeser, H. L. et al. (1986) - Detailed classification of condylar hyperplasia
- Olate, Sergio et al. (2013) - Considerations for diagnosis in consecutive patients
- Alyamani, Ahmed et al. (2012) - Management of patients with condylar hyperplasia
Condylar hyperplasia (mandibular hyperplasia) is over-enlargement of the mandible bone in the skull. It was first described by Robert Adams in 1836 who related it to the overdevelopment of mandible. In humans, mandibular bone has two condyles which are known as growth centers of the mandible. When growth at the condyle exceeds its normal time span, it is referred to as condylar hyperplasia. The most common form of condylar hyperplasia is unilateral condylar hyperplasia where one condyle overgrows the other condyle leading to facial asymmetry. Hugo Obwegeser et al. classified condylar hyperplasia into two categories: hemimandibular hyperplasia and hemimandibular elongation. It is estimated that about 30% of people with facial asymmetry express condylar hyperplasia.
| Condylar hyperplasia | |
|---|---|
| Other names | Mandibular hyperplasia |
In 1986, Obwegeser and Makek specifically detailed two hemimandibular anomalies, hemimandibular hyperplasia and hemimandibular elongation. These anomalies can be clinically present in a pure form or in combination.
