Relations between mandible-only advancement surgery, the extent of the posterior airway space, and the position of the hyoid bone in Class II patients: a three-dimensional analysis.

The objective of the present study was to evaluate the relation between mandibular advancement, the three-dimensional extent of the posterior airway space (PAS), and the position of the hyoid bone, using cone-beam computed tomography (CT). Twenty-eight Class II patients (21 women (mean (SD) age 29 (9) years) and seven men (mean (SD) age 23 (6) years)), who had had mandibular-only advancement surgery (Obwegeser-Dal Pont) were included in the study. In each case, cone-beam CT scans were taken one week before and six months after operation, and a retrospective analysis made of the alterations of several airway variables (volume, mean cross-sectional area, and diameter) and the three-dimensional extent of mandibular and hyoid movement, by using IPlan® cranial software. A linear regression was also done to correlate mandibular advancement, the movement of the hyoid bone, and airway variables. There were significant postoperative increases in all volumetric PAS variables, and in most diametric and spherical variables (p<0.05). There was also a significant linear relation between forward displacement of the mandible and the movement of the hyoid bone (p<0.05). These results show that mandible-only advancement surgery causes an increase in most dimensions of the PAS. This intervention can be assumed to reduce airway resistance and therefore might be a suitable treatment option for patients with obstructive sleep apnoea syndrome.

High oblique sagittal split osteotomy of the mandible: assessment of the positions of the mandibular condyles after orthognathic surgery based on cone-beam tomography.

High oblique sagittal split osteotomy is an orthognathic technique to move the mandible. Our aim was to evaluate changes in the position of the condyle in the glenoid fossa and its angulation before and after high oblique sagittal split osteotomy (HSSO). Fifty patients (32 women and 18 men, mean age 26.3 (SD 7.4) years) had cone-beam computed tomographyic (CT) scans before operation, immediately postoperatively, and before removal of the osteosynthesis nine months postoperatively. The images were analysed to look for changes in the sagittal, coronal, and axial positions of the condyles. Twenty-four patients with class II malocclusion had a mean (SD) mandibular advancement of 6.51 (2.41) mm, and 26 patients with class III malocclusion had a mean (SD) mandibular setback of 4.16 (2.77) mm. The joint space increased significantly (p<0.05) relative to baseline immediately postoperatively, but there was no significant increase at the nine-month follow-up. The changes in position in the sagittal, coronal, and axial planes were comparable. Despite there being a short proximal joint-bearing segment, the results indicate that this technique allows free-hand condylar positioning into the fossa safely without any clinically relevant dislocations.

Intracranial volume (ICV) in isolated sagittal craniosynostosis measured by 3D photocephalometry: A new perspective on a controversial issue.

BACKGROUND: There are still controversies regarding the intracranial volumes in patients with isolated sagittal craniosynostosis compared to a healthy population. This study aimed to compare the intracranial volume of children with sagittal synostosis and scaphocephaly to an age- and gender-matched control cohort using three-dimensional (3D) photogrammetry. METHODS: 62 boys and nine girls with sagittal craniosynostosis were included in this study. The intracranial volume was measured at the first clinical presentation. However, 3D photogrammetry was performed at children not younger than 3 months. The 3D photogrammetric data of 547 healthy boys and 287 healthy girls between the ages of 3-10 month was analyzed to establish an age- and gender-matched control group. RESULTS: Male patients with sagittal synostosis showed a significantly reduced intracranial volume compared to the reference group. For female patients, the intracranial volume was slightly lower compared to the norm group, but not significantly. CONCLUSIONS: Male children with sagittal synostosis showed significantly decreased intracranial volume between the age of 3 and 10 months compared to an age- and gender-matched control group. Female patients in the same age group presented a lower intracranial volume compared to the norm group. Measuring intracranial volume using 3D photogrammetry is a comparable and valuable alternative to CT scans that leads to a significant reduction of radiation exposure to the growing brain.

Long-term results in nonsyndromatic unilateral coronal synostosis treated with fronto-orbital advancement.

Children with unilateral isolated coronal suture synostosis suffer from frontal plagiocephaly. In this retrospective study we analyzed 21 patients who were treated with an identical and standardized surgical technique of fronto-orbital advancement with hypercorrection with an average follow-up of 57.5 months. The median age at surgery was 12.1 months. The median average amount of blood loss during the operation was less than 188 ml. Not a single major complication was observed. According to the classification of Whitaker, 15 patients had a Class 1 outcome, with excellent surgical results. Three patients were defined as Class 2 outcome. One of our patients was Class 3 and two patients were Class 4 because of severe forehead retrusion and temporal hollowing. Re-operation rate was 14.3%. 67% of our patients showed a correction or an improvement of the typical C-shaped deformity in their follow-up examination. Aesthetic outcomes were excellent in 13, good in 5, and poor in 3 of cases, as judged by their families and the craniofacial team. Unilateral coronal synostosis can be successfully treated by fronto-orbital advancement with a low complication rate and an excellent clinical outcome. To minimize the need of re-operations, fronto-orbital advancement should be performed with an overcorrection on the affected side.

Chiari malformation in nonsyndromal single craniosynostosis--much ado about nothing?

BACKGROUND: The significance of Chiari malformation in nonsyndromal-isolated craniosynostosis is still not well documented. Hence, in the present study we investigated the incidence of Chiari malformation in a larger series of patients with nonsyndromic-isolated single-suture craniosynostosis over a 9-year period using preoperative magnetic resonance imaging (MRI). METHODS: Of 215 children who had undergone surgery for nonsyndromic-isolated craniosynostosis, 89 cases (41.4 %) had MRI prior to surgery. All MRIs were screened for Chiari malformation. RESULTS: Only one patient (1.1 %) with isolated lambdoid synostosis showed Chiari malformation preoperatively, which was defined as a cerebellar tonsillar descent greater than 5 mm below the foramen magnum. However, no clinical symptoms were associated with Chiari malformation in this patient. CONCLUSIONS: As Chiari malformation is more likely to be associated with syndromic craniosynostosis, nonsyndromic bilateral coronal synostosis, or synostosis of the lambdoid suture, a general use of MRI as a screening tool for Chiari malformation should not be recommended for patients with nonsyndromic-isolated craniosynostosis who lack clinical symptoms.

Subtotal cranial vault remodelling in anterior sagittal suture closure: impact of age on surgical outcome.

Isolated fusion of the sagittal suture is usually treated before 1 year of age, but some patients present at a later age. The aim of this study was to evaluate the impact of children's age on the surgical outcome. The authors investigated 46 patients with isolated nonsyndromic sagittal craniosynostosis limited to the anterior two-thirds of the cranial vault. All patients underwent subtotal cranial vault remodelling, 36 patients (78.3%) before the age of 12 months (mean 8.92 months) and 10 patients after the age of 12 months (mean 15.77 months). Perioperative parameters and measurements of the cephalic index, preoperatively and postoperatively, were evaluated. All 46 patients showed improved head shape independent of their age. In patients younger than 12 months, mean cephalic indices improved from 65.99 to 74.49 (p<0.0001) and in patients older than 12 months from 66.38 to 74.38 (p<0.0004). There were no statistical differences in perioperative parameters including length of surgery, intraoperative blood loss and duration of hospital stay. In this study, patients showed no significant differences in surgical outcome that could have been related to the age at surgery. Surgical treatment should be performed early enough to benefit from the remodelling potential of the skull.

Surgical outcome after using a modified technique of the pi-procedure for posterior sagittal suture closure.

Fusion of the sagittal suture is the most prevalent form of craniosynostosis. Due to the variety of deformities of scaphocephaly depending on the location of the fused sagittal suture, the surgical procedure has to be adjusted to the individual case. In this study, 38 patients with a predominantly posterior sagittal suture closure were treated with a modified technique of the pi-procedure and the surgical outcome has been evaluated with respect to complications, morphological and aesthetic outcome. The improvement of the cephalic index in our series in the follow-up examination (mean 60.1 months) after surgery was significant (p<0.0001). According to the classification of Whitaker, 31 patients had a Class 1 outcome, with excellent surgical results. Aesthetic outcomes were excellent in 29, good in 5, and poor in 4 of cases, as judged by both the families and the craniofacial team. No severe complications have been observed. Posterior sagittal suture with marked occipital bulging can be successfully treated with this modified posterior procedure with a low complication rate, significant improvement of the cephalic index and a good aesthetic outcome. In all cases of sagittal synostosis, the operative procedure should be tailored to the nature and severity of the deformity.

[Surgically assisted rapid maxillary expansion. Effects on the nasal airways and nasal septum]. / Chirurgisch unterstützte transversale Oberkieferdistraktion. Auswirkungen auf Nasenwege und Nasenseptum.

BACKGROUND: Surgically assisted rapid maxillary expansion (SARME) is a standardized method to treat cross bites in maxillofacial surgery. Changes to the nasal airways are assumed due to the anatomic dependence between the palate and the nasal floor. PATIENTS AND METHODS: In this study 19 patients with a transverse deficit of the upper jaw underwent SARME. CT scans were performed 1 month pre- and 6 months postoperatively. Effects to the lower nasal airways, the nasal septum and the hard palate were subsequently evaluated. RESULTS: The mean distraction width of the upper jaws was 5.84 mm (SD 2.19) postoperatively. In addition to the dentoalveolar gain in width, a significant increase in the nasal floor was observed (p<0.001). The anterior part of the nasal floor was increased by 14.11%. An anterior-caudal tilt of the upper jaw was observed in the anterior part measuring 1.5 mm (SD 1.05). No significant deviation of the nasal septum occurred. CONCLUSION: SARME has a significant effect on ear, nose and throat medicine. Nasal airways enlarge significantly, while no significant deviation of the nasal septum is observed.

[CT assisted mandibular osteodistraction with reconstruction of the temporomandibular joint and two piece maxilla]. / CT-basierte Distraktion des Unterkiefers mit Gelenkrekonstruktion und Impaktation der Maxilla bei Kiefergelenkankylose.

BACKGROUND: The possibilities for computer assisted planning and its surgical conversion with stereolithographic templates are shown for complex maxillofacial surgical interventions. CASE REPORT: We describe the case of a patient with extreme micrognathia due to an ankylosis of the temporomandibular joint. In addition to the exact determination of the osteotomy lines on the mandibular angle and the segment osteotomy of the maxilla, vectors of the bidirectional osteodistraction were also predictable. CONCLUSION: In comparison with the conventional procedures, computer assisted planning achieved a much higher degree of precision and safety with reduced complication rates. The CMF module is a component of the SimPlant software which enables the precise planning of osteotomies and osteodistractions.