Marcus Sterz | PubMed Health

PubMed2003

Evaluation of condylar translation by sonography versus axiography in orthognathic surgery patients.

PURPOSE: This study compares measurement of the condylar translation by sonography or axiography in preoperative assessment and follow-up of orthognathic surgery patients. PATIENTS AND METHODS: Forty-seven moderately dysgnathic patients had consecutive examinations by axiography and sonography in a blind fashion at a single time point by 2 observers. Thirty-nine different dysgnathic patients, scheduled for isolated Le Fort I osteotomy, had preoperative condylar translation and 24-month follow-up measured randomized by either axiography (25 patients as control group) or sonography (14 patients as study group). RESULTS: The examination time for axiography was 20 minutes average versus 2 minutes for sonography. The mean differences were 1.7 mm in opening, 2.1 mm in protrusion, and 3.3 mm for mediotrusion. Pearson's proportionality quotient was r = 0.75, analysis of variance (P <.95, F = 3.9, alpha =.05 significance level) was not significant. The 24-month longitudinal follow-up showed a Pearson's proportionality quotient of r = 0.7 between study and control group, and no significant difference in analysis of variance (P <.075, F = 2.81, alpha =.05 significance level). CONCLUSION: Sonography proved adequate for assessment and follow-up of condylar translation compared with axiography in orthognathic surgery patients. Temporomandibular joint sonography was faster and more comfortable, allowed 1-week postoperative examination and reexaminations, and was equally exact. Anatomic details like joint degeneration and disc displacement could be assessed. However, sonography did not measure the inclination of the condylar track.

Adolescent↗

PubMed2003

Proximal segment positioning in bilateral sagittal split osteotomy: intraoperative controlled positioning by a positioning splint.

PURPOSE: Most techniques of proximal segment positioning hinder intraoperative condyle displacement. However, merely maintaining condylar position cannot optimize the preoperative condyle-disc-fossa relationship. This study attempts to optimize condylar position in the osteotomy patient. PATIENTS AND METHODS: A study group of 23 bimaxillary operated patients had intraoperative joint positioning by positioning splint and plates (9 Angle Class II, 14 Class III). After assessing the habitual and appraising the optimized condyle position on preoperative sonograms and magnetic resonance images, positioning splints were constructed as acrylic occlusal wafers in a semi-individual articulator. Set in occlusion before adaptation of positioning plates, they were intended to move the condyles into the calculated position. Eighteen bimaxillary operated control patients had conventional plate positioning according to the habitual occlusion (9 Angle Class II, 9 Class III). Clinical follow-up, axiography, or sonography was maintained for 24 months. Preoperative lateral cephalograms were scrutinized for horizontal and vertical joint spaces and compared with the immediate postoperative radiography. RESULTS: Postoperative Class II study group patients had less dorsal and more vertical joint space and Class III patients more dorsal and vertical space compared with the controls. The study group exhibited significantly less postoperative dysfunction compared with the control group (2-way analysis of variance: P <.021, F = 9.2, alpha =.05 significance level), disc dislocation prevalence was lower (P <.07, F = 9.2), postoperative changes in condylar translation were smaller (P <.014, F = 4.9), and 8% skeletal relapses versus 22% in the controls were seen. CONCLUSIONS: A proximal segment-positioning splint effectively positioned the condyle in the desired direction, but with considerable relapse, significantly reduced postoperative dysfunction, disc dislocations, changes to the condylar translation, and incidence of skeletal relapse at 24-month follow-up.

Adolescent↗