Faculty Bibliography

BACKGROUND: Bilateral cleft lip-cleft palate is associated with nasal deformities typified by a short columella. The authors compared nasal outcomes of cleft patients treated with banked fork flaps to those of patients who underwent nasoalveolar molding and primary retrograde nasal reconstruction. METHODS: A retrospective review of 26 consecutive patients with bilateral cleft lip-cleft palate was performed. Group 1 patients (n = 13) had a cleft lip repair and nasal correction with banked fork flaps. Group 2 patients (n = 13) had nonsurgical columellar elongation with nasoalveolar molding followed by cleft lip closure and primary retrograde nasal correction. Group 3 patients (n = 13) were age-matched controls. Columellar length was measured at presentation and at 3 years of age. The number of nasal operations was recorded to 9 years. The Kruskal-Wallis and Tukey-Kramer tests were used for statistical analysis. RESULTS: Initial columellar length was 0.49 +/- 0.37 mm in group 1 and 0.42 +/- 0.62 mm in group 2. Post-nasoalveolar molding columellar length was 4.5 +/- 0.76 mm in group 2. By 3 years of age, columellar length was 3.03 +/- 1.47 mm in group 1, 5.98 +/- 1.09 mm in group 2, and 6.35 +/- 0.99 mm in group 3. Group 2 columellar length was significantly greater (p < 0.001) than that of group 1 and not statistically different from that of group 3 (p > 0.05). All group 1 patients (13 of 13) needed secondary nasal surgery. No nasoalveolar molding patients (zero of 13, group 2) required secondary nasal surgery. CONCLUSION: Nonsurgical columellar elongation with nasoalveolar molding followed by primary retrograde nasal reconstruction restored columellar length to normal by 3 years and significantly reduced the need for secondary nasal surgery.

BACKGROUND: Unilateral craniofacial microsomia is characterized by soft-tissue and bony deficiencies. Mandibular distraction osteogenesis can be used to augment the hypoplastic skeleton and improve facial symmetry. The aim of this study was to determine how the vector of unilateral mandibular distraction affects treatment outcomes. METHODS: A retrospective chart and radiographic review was conducted of all patients treated with external mandibular distraction osteogenesis between October of 1990 and February of 2004 (n = 185). A subset of 42 patients underwent primary unilateral, uniplanar, external distraction, and 13 patients were found to have satisfied inclusion criteria and had adequate predistraction and postdistraction lateral and posteroanterior cephalograms. Cephalometric tracings were made and multiple points and planes were assessed before and after distraction. RESULTS: A strong correlation was noted between the vector of distraction and the movement of the mandible. A horizontal vector of distraction resulted in minimal increase in ramal length but a marked shift in the mandibular midline (r = 0.68, p < 0.05). In contrast, a vertical vector of distraction resulted in marked mandibular ramus lengthening but minimal mandibular midline shift (r = 0.73, p < 0.05). Mathematical formulas were derived to correlate the distraction vector and mandibular movements to improve preoperative planning. CONCLUSIONS: Successful distraction is dependent on accurate preoperative planning and prediction of outcomes. This study demonstrates a predictable relationship between the vector of unilateral distraction and the mandibular response

BACKGROUND: The application of distraction osteogenesis is an effective treatment for mandibular deficiencies. A priori, a horizontal vector of distraction was hypothesized to produce horizontal movement of the mandible and a vertical vector of distraction to produce primarily downward vertical elongation of the ramus. This study was designed to test this hypothesis. METHODS: A retrospective clinical and radiographic review was conducted of all patients who underwent bilateral, uniplanar distraction with an external device at the New York University Medical Center between October of 1990 and February of 2004 (n = 185). A subset of 15 patients was identified who satisfied inclusion criteria and had adequate predistraction and postdistraction lateral cephalograms. Cephalometric tracings were made and multiple landmarks were assessed before and after distraction. RESULTS: A strong correlation was noted between the vector of distraction and rotation of the symphyseal plane, movement of the mandibular symphysis, and change in interocclusal angle. A horizontal vector of distraction resulted in minimal counterclockwise rotation of the symphyseal plane, greater downward vertical translation of the mandibular symphysis, and minimal closure of an anterior open bite. In contrast, a vertical vector resulted in greater counterclockwise rotation of the symphyseal plane, greater horizontal projection of the mandibular symphysis, and greater closure of an anterior open bite. Mathematical formulas were derived to correlate the distraction vector and mandibular movements. CONCLUSIONS: Successful distraction is dependent on accurate prediction of outcomes. This study demonstrates that the vector of distraction predictably affects the mandibular response during bilateral distraction osteogenesis but contradicts the a priori hypothesis

Although recent studies indicate that regional dura mater influences the fate of the overlying cranial suture, little is known about the assembly of extracellular matrix (ECM) molecules within the patent and fusing murine cranial suture complexes. Confocal laser scanning microscopy was used to study ECM assembly within patent and fusing cranial suture complexes. Coronal sections (20 microm thick) of patent sagittal (SAG) and fusing posterior frontal (PF) sutures from postnatal 8-, 14-, and 18-day-old Sprague-Dawley rats were scanned in 0.5-microm increments, and images were collected consecutively to create a z-series for three-dimensional reconstruction. Spatial and temporal collagen arrangements were compared between SAG and PF sutures by measuring interfiber distance, fiber thickness, and total collagen surface area at each time point.We demonstrate that on day 8 (before the onset of suture fusion), collagen bundles are randomly arranged in both the SAG and PF sutures. By day 14 (midfusion period), there was a statistically significant reduction in total collagen surface area (80.5% versus 67.4%; P < 0.05) as the collagen bundles were organized into orthogonal lattices along the anterior and endocranial margins of the PF suture. Furthermore, new bone matrix deposition was observed along the edges of these organized collagen bundles. In contrast, collagen within the SAG suture remained randomly arranged and unossified. By day 18 (late fusion period), the PF suture was completely fused except for the posterior-ectocranial portion. This patent section of the PF suture contained a highly organized mineralizing orthogonal collagen lattice. The total collagen surface area in the day-18 PF suture continued to decline compared with the day-8 PF suture (80.5% versus 55.6%; P < 0.05). In the day-18 SAG suture, the collagen bundles remained randomly arranged, and the total surface area did not change. The same analysis was performed in a human pathologic fusing and patent suture. Similar results were observed. The total collagen surface area significantly decreased in the pathologic fusing human suture compared with the patent suture (92.8% versus 60.6%; P < 0.05). Moreover, the pathologically fusing suture contained a highly organized mineralizing orthogonal collagen lattice. This is the first analysis of collagen patterns in patent and fusing cranial sutures