Clinical Practice Guideline: Condylar Hyperplasia of the Mandible—Diagnosis and Treatment

Abstract

Background: Condylar hyperplasia of the mandible is characterized by abnormal size and configuration of the condylar process. In Germany, the administrative prevalence of diagnosed and/or treated condylar hyperplasia is 2.4-9.6 cases per 100 000 persons. Misdiagnosis is common and can lead to severe esthetic and functional complications, including facial deformity that can progress into the patient's twenties, as well as dysfunctional speech and mastication.

Methods: We conducted a systematic review of the literature and a structured consensus-finding process with the Delphi method.

Results: The experts recommend timely diagnosis of condylar hyperplasia so that its progression can be prevented by appropriate treatment. The basic diagnostic evaluation consists of history taking, physical examination, and imaging with orthopantomography. If condylar hyperplasia is confirmed, three-dimensional imaging is performed, usually with SPECT. The treatment is mainly surgical: partial condylectomy techniques and orthognathic surgery are the most common methods. If left untreated, the disorder causes severe dysfunction of mastication as well as disfigurement. Most studies of treatments for condylar hyperplasia have been based on low case numbers and have yielded only level 4 or level 5 evidence.

Conclusion: Condylar hyperplasia is a common, but not widely known problem. Its early diagnosis and treatment can prevent severe jaw asymmetry and further complications such as craniomandibular dysfunction and arthrosis of the temporomandibular joints.

Figure 1

Overview of systematic literature search for the search period 05/2015 to 09/2023; at this time, there were already 88 sources available from the previous guideline. AWMF, Association of the Scientific Medical Societies; Cochrane, Cochrane Library; Livivo, internet-based search portal of the ZB MED – Information Center for Life Sciences; NICE, National Institute for Health and Care Excellence; PubMed, text-based meta-database offering access to the databases MEDLINE, OLDMEDLINE (before 1966), and PubMed Central; www.guideline.gov, Agency for Healthcare Research and Quality

Figure 2

Case example of seemingly only discrete facial asymmetry in a patient with condylar hyperplasia on the right side of the face (a). The extent of the asymmetry becomes clear on intraoral inspection (b) revealing the oblique occlusal plane. The teeth of the right upper jaw are elongated to compensate; note the caudal position of the mandibular basal arch on the right, which will require complex corrective measures.

Figure 3

Imaging studies of the patient in Figure 2: A total of four surgical procedures were performed to correct the condition: a) Preoperative orthopantomogram showing a hyperplastic condyle (arrow). Note the asymmetry of the mandibular body. b) Postoperative orthopantomogram following bimaxillary corrective osteotomy (2^nd procedure; yellow arrow) for occlusal plane compensation after high condylectomy had been performed in a previous surgery step (1^st procedure; white arrow). c) Postoperative orthopantomogram following nerve transfer surgery and resection of an intermediate bone segment (3^rd procedure; dotted line); the preoperative asymmetrical basal margin of the mandible is now symmetrical; hardware removal is yet to be performed (4^th procedure).

Figure 4

a) corrected occlusal plane after surgery; b) restored bony facial asymmetry after surgery