原文題目(出處)： Condylar hyperplasia and facial asymmetry：Report of Five cases. J Maxillofac Oral Surg 2011;10:50-6
原文作者姓名： Dicya Mehrotra, Satish Dhasmana, Mala Kamboy, Gautam Gambhir
通訊作者學校： King George’s Medical University 報告者姓名(組別)： 莊涵芝 Intern F組
報告日期： 101.02.17
內文：
Abstract
Condylar hyperplasia of mandible is overdevelopment of condyle, unilaterally or bilaterally, leading to facial asymmetry, mandibular deviation, malocclusion and articular dysfunction.
Introduction
Condylar hyperplasia normally occurs in mid teens with increasing deformity until cessation of growth.
Prominent features
enlarged mandibular condyle
elongated condylar neck
outward bowing and downward growth of body and ramus of mandible on affected side
causing fullness of face on that side and flattening of face on the contralateral side.
If deformity occurs
Before completion of growth—slanted occlusal plane
After completion of growth—posterior open bite
Unilateral condylar hyperplasia must be differentiated from other states of overdevelopment
Hemifacial hypertrophy
Unilateral macrognathia
Laterognathia
Chondroma
Osteochondroma Materials and methods
A total of five patients with the primary complaint of facial asymmetry due to condylar hyperplasia who visited the OPD of Oral and Maxillofaical Surgery, CSMMU, Lucknow between 2005 and 2006 were randomly selected
Informed consent was taken prior to their inclusion in the study
Age, sex and a detailed history of the mode of onset and duration were recorded
Any obvious facial asymmetry, scar mark or deviation of chin were examined
Radiological assessment of both the joints was carried out with orthopantomograms and CT scan.
Scintigraphy using 99mTc-MDP was used to distinguish the growing condyle
from non-growing one and to assess whether there was still phase of growth
The joint was exposed through Al-Kayat Bramley incision and a high condylar shave or condylectomy as planned, was carried out with the help of surgical bone cutting device. Specimen was sent for histopathological examination.
Saggital split osteotomy was planned and performed bilaterally, when gross asymmetry existed along with protrusion, and unilaterally, in case of minor discrepancies.
Results
Mean age：22.8 years
Trauma was the most common etiology
Condylar hyperplasia causes facial asymmetry followed by midline shift, protruded chin, contralateral crossbite, maxillary cant
Radiographic examination：change in shape of condylar head, elongated condylar neck, bowing of inferior border, hemimandibular enlargement
Treatment：condylectomy, high condylar shave (with good intercuspal dental relationship), bilateral sagittal split osteotomy (with gross facial asymmetry and prognathic mandible), unilateral sagittal split osteotomy
Histopathological examination ： thickened irregular bony trabeculae, uninterrupted layer of undifferentiated mesenchymal cells, hypertrophic cartilage, islands of chondrocytes in subchondral trabecular bone, increased thickness of cartilaginous layer
Patients were followed up regularly in their post-operative phase for a period of 2 years
Review of literature
Two types of deformity
Increased anteroposterior mandibular length
Buccal crossbite
Increased vertical ramus height
Tilted occlusal plane
Lateral open bite
Resulting in facial asymmetry and reduced opening on affected side
Additional factors：hormonal influences, hypervascularity, heredity, infection , trauma
Invariably unilateral
Diagnostic tools
Sequential study models, radiological and scintigraphic methods
For diagnosis and monitoing macroscopic aspects
Lateral and posteroanterior cephalograms
For possible differences in size, shape, and length of the R/L side
Micromorphology
Thickened and irregular bony trabeculae
Large volume of trabecular bone
Higher percentage of surfaces covered in osteoids
Histologically
Uninterrupted layer of undifferentiated germinating mesenchymal cells, hypertrophic cartilage, islands of chondrocytes in the subchondral trabecular bone
Increased cartilaginous layer
Isotope bone scan
Assess growth activity in the mandibular condyle
Distinguish normal bone growth from increased activity that may be the cause of the asymmetry
SPECT
More sensitive and accurate in detecting abnormal activity
Bone scintigraphy
Detect if the pathology is in an active phase or not
PET Scan
Successfully used in the assessment and management of condylar haperplasia
Treatment
Active growth—condylectomy
Growth stopped—orthodontics & surgical mandibular repositioning
Greatly increased height of the mandibular body—reduce the inferior border
Discussion
Treatment depends on age, degree of deformity and hypofunction
The basic consideration in the management of facial asymmetry secondary to condylar hyperplasia must include control of the growth process to allow more balanced facial development
Done by high condylectomy or condylar shave in actively growing cases
Surgery
Condylectomy
Active change in the hyperplastic condyle
Radiographic or clinical suggestions of pathologic conditions such as chondroma, osteoma, or other neoplasm
Restores symmetry
Allows histological examination
Unilateral ramus surgery
When neoplasm is not suspected
Shorten the affected ramus as condylectomy does
Vertico-sagittal ramus osteotomy—Useful particularly to treat vertical discrepancies
Osteotomy
If condyle is mature and stable, with normal function and cessation of growth
Compensatory growth has occurred
E.g. Spatial correction with Lefort Osteotomy
A slightly enlarged condyle that functions normally is left intact, and it may later remodel
Zhonghua investigated the TMJ function of the condylar hyperplasia patients after condylectomy
Dramatic improvement in facial asymmetry
New cortex formed
TMJ function was improved
Hence Condylectomy was an effective method
Patients with active condylar hyperplasia treated with high condylectomy, articular disc repositioning, and orthognathic surgery have stable, predictable outcomes compared with those treated with orthognathic surgery alone
Symmetry in most patients with condylar hyperplasia
Mandibular arch form remains approximately symmetric with the maxillary arcn
No major compensatory alveolar modifications
General contour of the displaced mandible is symmetric
Orthodontic treatment
Pre-surgical orthodontic treatment
Worsen the dental midline to allow greater osseous movements
Post-surgical orthodontic treatment
If ideal occlusion is desired
When skeletal and dental studies do not mandate orthodontic treatment pre-surgically
題號 題目
1 下列關於「下顎矢向分裂骨切開術（bilateral sagittal split osteotomy）的 敘述，何者錯誤？」
(A) 此種術式只能讓下顎骨往後退，無法讓下顎前移
(B) 術式是在下顎升枝內側面作水平的骨切開，在前緣作矢狀骨切開
以及在臼齒頰側面作垂直的骨切開
(C) 在骨切開區域產生了大面積骨質重疊的伸縮效應，具備多方向移
動的彈性
(D) 易傷害到下齒槽神經
答 案 ( A)
出處：Peterson’s Principles of Oral and Maxillofacial Surgery(2004), 2nd edition, edited by Michael Miloro
題號 題目
2 兩側矢向劈裂骨切開術（bilateral sagittal split osteotomy）可用來治療何 症？1.下顎前突症（mandibular prognathism）；2.下顎後縮症（mandibular retrognathism）
(A) 只有1 (B) 只有2 (C) 12
(D) 12均不正確 答 案 (
C)
出處：Contemporary Oral and Maxillofacial Surgery, Peterson, L. j., 1998 5th edition
