Mandibular reconstruction after excision of recurrent odontogenic keratocyst using a novel mandibular distraction osteogenesis method- a case report.

BACKGROUND: Odontogenic keratocyst is one of the most common benign odontogenic neoplasms with a high recurrence rate. Its resection has the potential to lead to mandibular segmental defects. In this case report, we describe a patient with odontogenic keratocyst who underwent radical resection using a novel distraction osteogenesis (DO) method to reconstruct mandibular segmental defect. CASE PRESENTATION: This case report describes a 19-year-old woman with odontogenic keratocyst of the mandible that recurred after multiple curettages and eventually necessitated radical resection. Mandibular segmental defect after radical resection was reconstructed using a novel DO method that involved directly contacting the segment ends of the defect without the transport disk. However, the distractor broke during the retention period, and a molding titanium plate was used for fixation. This novel distraction method achieved mandibular reconstruction and restored mandibular function and contour.

Correlation analysis of upper airway morphology in patients with obstructive sleep apnea and anatomically small retruded mandibles.

OBJECTIVE: To investigate the relationship between upper airway morphology and the severity of obstructive sleep apnea (OSA) in patients with anatomically small retruded mandibles. METHODS: Fifty-two patients with small retruded mandibles underwent polysomnography and airway computed tomography. The airway morphology parameters and sleep assessment were compared between the patients with or without OSA. RESULTS: Twenty-eight patients diagnosed with OSA, according to polysomnography, had a higher distance between the hyoid bone and mandibular plane (HMP), lateral dimension (LAT)/anteroposterior dimension (AP), but lower minimum cross-sectional area (mCSA), AP, surface area, volume, avgCSA, and airway uniformity (U). The apnea-hypopnea index had negative correlations with mCSA, AP, surface area, volume, avgCSA, and U, and had a positive correlation with HMP and LAT/AP. CONCLUSION: OSA is common among patients with small retruded mandibles and is associated with a more compressed upper airway shape and longer HMP.

Correction to: The Soft Tissue Angular Analysis of Facial Profile in Unoperated Adult Patients with Unilateral Cleft Palate.

Due to errors introduced during the production process, Tables were published incorrectly in the original publication of this article. The correct tables are given here.

The Soft Tissue Angular Analysis of Facial Profile in Unoperated Adult Patients with Unilateral Cleft Palate.

OBJECTIVE: The purpose of this study was to investigate the differences in facial profile development between unoperated adult cleft palate (UACP) patients and normal controls and to analyse the reasons for the differences. MATERIALS AND METHODS: A total of 50 individuals with a unilateral cleft palate and 20 normal controls were selected to undergo angular measurement of their facial profiles. Data with significant differences between the two groups were analysed. RESULTS: Seven angle measurements of the facial profile showed that the mid-facial protrusion of the UACP patients had no significant differences from the control group (p > 0.05). But their angle of the medium face (N'-Trg-Sn) was significantly lower than the non-cleft controls (p < 0.05), suggesting a worse vertical development of the middle face. A significantly larger nasal tip angle (Cm-Sn/N'-Prn) for UACP patients suggested they had a rounder and blunter nasal tip (p < 0.05). The soft tissue facial angle and chin-lip angle of UACP patients had significant differences from non-cleft controls (p < 0.05), but the head position angle (Sn-Sm-THP) had no significant difference between two groups (p > 0.05), which suggested a steep mandibular plane for UACP patients but without severe retraction of the chin. CONCLUSION: The development of facial protrusions in UACP patients is similar to that in normal adults, but the vertical development in the middle face is insufficient. Such hypoplasia may be related to the intrinsic deficiency of the maxilla. There is a tendency for flat nasal growth and insufficient development of the chin in UACP patients. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Dynamic Analysis of New Bone Obtained by Nonvascular Transport Distraction Osteogenesis in Canines.

PURPOSE: The aim of the present study was to construct a nonvascular transport disc to repair the canine mandibular defects model and to perform a dynamic analysis of the new bone obtained by nonvascular transport distraction osteogenesis (NTDO) in canines. MATERIALS AND METHODS: Thirty adult dogs were randomly divided into 3 groups, with 10 dogs in each group. Canine mandibular defect models of NTDO were constructed. All the dogs were marked by tetracycline hydrochloride at a different distraction stage. The dogs were euthanized at 2, 4, and 12 weeks after distraction, and the quality ratio of calcium and phosphate for the new bone was measured using electron dispersive spectroscopy. RESULTS: The canine mandibular defects were successfully repaired. Using tetracycline hydrochloride, we successfully observed the quality and speed of new bone formation. The quality ratio of calcium and phosphate was similar between the new bone formation and the original bone. The time spent using a nonvascular transport disc to repair mandibular defects was consistent with using a vascularized transport disc, and the quality of the new bone and the original bone was exactly the same. CONCLUSION: When the bone mass is insufficient or the conditions are not suitable for a vascularized transport disc, the nonvascular transport disc can be used as an alternative.

[Application of joint reconstruction with autogenous coronoid process graft to treat temporomandibular joint ankylosis].

PURPOSE: To evaluate the clinical effect of joint reconstruction by using autogenous coronoid process graft to treat temporomandibular joint(TMJ) ankylosis. METHODS: Nine cases of TMJ ankylosis from September 2008 to September 2010 were surgically treated by joint reconstruction with autogenous coronoid process graft, using autogenous articular disc or prosthodontic membrane as interpositional material. Mouth opening, occlusion and cone beam CT(CBCT) were used for evaluation before and after surgery. RESULTS: Satisfactory mouth opening was achieved in all patients and no one got occlusal changes or reankylosis during follow-up. CBCT showed that coronoid process graft reached bone union with the ramus and turned to be round. CONCLUSIONS: It is effective to cure TMJ ankylosis through joint reconstruction with autogenous coronoid process graft.

[Cloning of human bone morphogenetic protein-2 gene and the construction of its eukaryotic expression vector].

OBJECTIVE: To clone human bone morphogenetic protein-2 (hBMP2) gene and construct its eukaryotic expression vector pcDNA3.1 -hBMP2. METHODS: Human BMP2 gene was amplified by RT-PCR method from human osteosarcoma cells and constructed into eukaryotic expression vector pcDNA3.1-hBMP2. The gene in the vector pcDNA3.1-hBMP2 was identified by PCR amplification, enzyme digestion and DNA sequencing. RESULTS: The cloned DNA was confirmed to be hBMP-2 gene. CONCLUSION: In this study, hBMP2 gene is successfully cloned and its eukaryotic expression vector pcDNA3.1-hBMP2 is constructed, which provides the foundation of using BMP2 gene therapy to accelerate new bone formation in distraction osteogenesis.