Cephalometric craniofacial characteristics in patients with temporomandibular joint ankylosis.
BACKGROUND
The sequelae of temporomanibular joint (TMJ) ankylosis include limitation of jaw movement, interference of oral function and affects on the craniofacial growth. Analysis of the craniofacial form of TMJ ankylosis offers guidelines for managing this disease.


METHODS
Forty-five patients with intraarticular TMJ ankylosis were collected from the files at the Chang Gung Craniofacial Center. There were 21 male and 24 female patients, aged 3 to 47 years. Thirty-seven patients were unilaterally affected and eight had bilateral involvement. Patients were grouped according to gender and age. Both the medical history and onset of the disease were investigated in all patients. The pretreatment lateral cephalograms were used for analysis. The variables were compared with the Chinese norms with corresponding sex and age groups.


RESULTS
The etiology included 48.9% facial trauma history, 17.8% traumatic delivery or birth injury, 15.6% middle ear or dental infection, 2.2% chronic arthritis and 15.6% unknown causes. The onset of mouth opening limitation was under 16 years of age. The average total mandibular length was less than the norm by 30 mm. Each patient presented with a mandible that had backward rotation with chin recession. Accentuated antegonial notch and inferiorly located condyle were observed on the affected side. The maxilla was shorter and the ANB was larger than the norm by 10 degrees but the overbite and overjet were within normal ranges.


CONCLUSIONS
The facial growth was severely disturbed in terms of dimension, morphology and direction of growth in patients with TMJ ankylosis. Better management of mandibular fractures, good infection control and early treatment intervention are ways to reduce the influence on craniofacial growth.
Ko
Ellen Wen-Ching
EW
Department of Orthodontics and Craniofacial Dentistry, Chang Gung Memorial Hospital, Taipei, Taiwan. ellenko@seed.net.tw
Huang
Chiung-Shing
CS
Chen
Yu-Ray
YR
Figueroa
Alvaro A
AA
D000293:Adolescent; D000328:Adult; D000844:Ankylosis / Q000209:etiology / Q000473:pathology*; D002508:Cephalometry; D002648:Child; D002675:Child, Preschool; D005147:Facial Bones / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology*; D008875:Middle Aged; D012886:Skull / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000209:etiology / Q000473:pathology*