Condylar restoration after early TMJ fractures and functional appliance therapy. Part I: Remodelling

The aim of this study was to measure quantitatively and to analyze the process of condylar restoration during and after functional appliance therapy with an activator in children and juveniles who had sustained condylar fractures. Spiral computed measurement of condylar morphology was performed in order to quantify the association described in the literature between condylar remodelling and age as well as certain types of fracture. Nineteen patients with an average age of 13.4 years, who had sustained a functionally treated unilateral condylar fracture 4.9 years earlier on average, were included in the present study as the follow-up group. Twenty patients, who had sustained a unilateral fracture at an average age of 8.1 years and had been treated functionally for 6 to 8 months, formed the treatment group. The condylar dimension and the condylar neck length of the ipsilateral and of the contralateral temporomandibular joints were measured from the axial and parasagittal reconstructions and were compared on the basis of sex, age and fracture type. The mediolateral condylar dimension of the follow-up group showed a sex-specific difference of 0.2 cm on the contralateral side and 0.4 cm on the ipsilateral side. The fracture side condyle indicated a relative mediolateral decrease of 4.2% and an anteroposterior increase of 12.6%. Shortening of the condylar neck and excessive bony overgrowth were found to occur more often in fractures with displacement and in low fracture types. The "10-plus" subgroup at time of trauma showed a significantly greater variation and greater differences in mediolateral and anteroposterior condylar dimension than the younger patients.