Mandibular widening in hemifacial microsomia: a roentgen stereometric study of 11 patients with the aid of metallic implants.

INTRODUCTION: Our objective was to study mandibular widening in untreated subjects with hemifacial microsomia. METHODS: From the 3-dimensional files at the Department of Plastic and Reconstructive Surgery, Skane University Hospital in Malmö, Sweden, data of 11 subjects (3 girls, 8 boys) with hemifacial microsomia were retrieved. Their age range was 9 years 2 months to 13 years 2 months at the first examination. The mean observation period was 5 years 2 months. Each subject was studied by roentgen stereophotogrammetry with the aid of metallic implants. RESULTS: A significant widening of the mandible was found, with a mean total change of 0.31 mm (range, 0.08-0.79 mm) and a mean annual change of 0.07 mm (range, 0.03-0.12 mm). In 2 subjects, narrowing of the mandible was found: -0.16 and - 0.23 mm. CONCLUSIONS: The mandible got wider during adolescence in 9 of our subjects with hemifacial microsomia but to a lesser extent than has been reported in subjects without hemifacial microsomia and from ordinary orthodontic clinics. Sex difference was not addressed. It was suggested that chewing (forces and patterns) was responsible for the mandibular widening in our subjects; this is in line with previous research.

Maxillary and mandibular displacement in hemifacial microsomia: a longitudinal Roentgen stereometric study of 21 patients with the aid of metallic implants.

OBJECTIVE: To record maxillary and mandibular displacement with articular growth and in response to bimaxillary surgical repositioning in patients with hemifacial microsomia (HFM) and to observe ipsilateral corpus/ramus growth in severely affected children. DESIGN: Prospective roentgen stereometric analysis (mean age 7 years 10 months to 18 years 0 months) and retrospective profile and panoramic roentgenograms. Mean total observation period was 9 years 1 month. SETTING: Department of Plastic and Reconstructive Surgery, Malmö University Hospital (Malmö, Sweden). PATIENTS: Twenty-one patients consecutively diagnosed from 1976 through 1988 with HMF, five of whom had bimaxillary surgery. INTERVENTIONS: Surgery was performed at the Department of Plastic and Reconstructive Surgery. Implants were inserted at the initial reconstructive surgical procedure under general anesthesia. Roentgen examinations were performed in connection with continued clinical evaluations and treatment. MAIN OUTCOME MEASURES: Stereo roentgenograms were digitized at the Department of Orthopedic Surgery, Malmö University Hospital (Malmö, Sweden). RESULTS: Displacement of the jaws with articular growth and in response to bimaxillary surgical repositioning varied interindividually with no apparent common pattern. Relapse displacement occurred several years after bimaxillary surgery. Mandibular growth changes were found in the corpus/ramus area and alveolar process on the affected side. CONCLUSIONS: A marked interindividual variability of maxillary and mandibular displacement indicates that the relevance of statistical analysis of HFM growth data may be questioned. We would suggest that precise and accurate longitudinal recordings of growth and response to surgery in individual HFM patients be more appropriate.