Effects of combined orthodontic-orthognathic treatment for class II and III correction on posterior airway space : Comparison of mono- and bignathic osteotomies.

OBJECTIVES: Comparison of treatment effects on the posterior airway space (PAS) in patients treated with combined orthodontic-orthognathic surgical treatment. METHODS: Pre- and postsurgical lateral cephalograms of 53 (34 females, 19 males) Caucasian patients were analyzed using a customized set of measurements. According to malocclusion (Class II or III) and surgical approach (either monognathic or bignathic), patients were allocated into four groups. PAS was assessed from cranial to caudal at six levels (P1-P6). Paired t tests were used for intragroup and t tests for independent samples for intergroup comparisons. Results were considered statistically significant at p < 0.05. RESULTS: In patients treated for Class II malocclusion, PAS retropalatally (P1 level) almost remained unchanged, whereas measurements at levels P2-P6 showed a mean increase ranging from approximately 2-5.5 mm. Significant changes were most pronounced in monognathic Class II patients (group 1) at levels P2-P4 with mean values ranging from approximately 3.7-5.5 mm. In patients treated for Class III malocclusion (groups 3 and 4), measurements at the P1 level almost remained unchanged in patients who underwent mandibular setback surgery (group 3), whereas the same measurements exhibited significant increase (>6 mm) in patients treated with bignathic surgery (group 4). CONCLUSIONS: Bignathic surgery led to smaller changes of pharyngeal depth in Class II and III patients than monognathic surgery. Alterations of the PAS due to orthognathic surgery should be considered during orthodontic and presurgical treatment planning.

Diagnostic delay of NF1 in hemifacial hypertrophy due to plexiform neurofibromas.

Benign tumors of the peripheral nerve sheath, termed neurofibromas, are the hallmark feature of neurofibromatosis type 1 (NF1). These tumors can result in hypertrophy of a limb or another anatomic region. Hemifacial hypertrophy due to an underlying neurofibroma is a typical manifestation of NF1 in young children although the overall frequency of facial involvement is low. We retrospectively studied all patients, which were referred to our outpatient clinic because of hemihypertrophy or swelling of the face for initially unknown reason with a final diagnosis of NF1. A total number of six patients were identified. Clinical and radiological characteristics of these patients were analyzed. In all patients, diagnosis of NF1 could be established based on the typical clinical criteria. However, despite other typical NF1-associated features (e.g. multiple café-au-lait spots) diagnosis of a plexiform neurofibroma as underlying cause for the hemifacial hypertrophy was significantly delayed in all patients. MRI scans were misinterpreted in all of the cases as lymphangioma because plexiform neurofibromas can resemble mesenchymal tumors or lymphangiomas. NF1 has to be considered in the differential diagnosis of hemifacial hypertrophy. A thorough clinical examination of affected patients should focus on typical disease-defining features. Early diagnosis of NF1 can prevent unnecessary treatment at least in some patients.