[Effect of oral appliance on reproductive system of the male New-Zealand rabbit with obstructive sleep apnea-hypopnea syndrome].

Objective: To observe the effect of the mandible advanced device on the reproductive system of the male New-Zealand rabbit with obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods: Thirty male New-Zealand white rabbits were randomly divided into three groups (with 10 rabbits in each group): sleep apnea-hypopnea syndrome group (group OSAHS), mandible advanced device group (group MAD) and control group. On the basis of the OSAHS animal model, mandible advanced devices were used for group MAD animals. After intervention for 8 weeks (sleeping by dorsal position, 4-6 hours/d), the samples were gained from the animals under general anesthesia and observed under the transmission electron microscope (TEM) and the AX-80 universal microscope. The cauda epididymis was obtained to be observed the number, viability, motility and abnormal rate of spermatozoa. Results: Compared with the control group, the upper airway space, the saturation of blood oxygen, partial pressure of oxygen, pH, the number, viability rate and motility rate of spermatozoa in cauda epididymis of the group OSAHS were significant decreased (all P<0.05), and the partial pressure of carbon dioxide and the rate of teratospermia was significant increased (both P<0.05). But compared with the control group, these indexes mentioned above in the group MAD showed no statistical significance (all P>0.05). TEM and the light microscope showed that the status of spermatogenic cell, seminiferous tubule and spermatogenic epithelium was improved in the group MAD. The correlation analysis showed that the saturation of blood oxygen had a negative correlation with the rate of teratospermia (r=-0.614, P<0.001). Conclusion: The damage of spermatogenic cells and the decrease of the sperm quality caused by OSAHS in New-Zealand rabbits could be improved by the mandible advanced devices.

[Effect of mandibular advancement device upon nuclear factor κB and tumor necrosis factor α, interleukin 6 in genioglossus of rabbit with obstructive sleep apnea hypopnea syndrome].

Objective: To investigate the effects of mandibular advancement device (MAD) upon nuclear factor κB (NF-κB), tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) in the genioglossus. Methods: Eighteen New Zealand white rabbits (male, six months old), in accordance with the random number table, were equally divided into three groups, the control group, obstructive sleep apnea hypopnea syndrome (OSAHS) group and MAD group. All animals were induced to sleep in supine position for 2 hours every morning in the next 8 weeks. The specimens of genioglossus were prepared. The relative expression of NF-κB p65 was measured with Western blotting and the mass concentration of TNF-α and IL-6 was determined with enzyme-linked immunosorbent assay. Results: The relative expressions of NF-κB p65 protein in genioglossus in the control group, OSAHS group and MAD group were 0.24±0.07, 0.44±0.08 and 0.30±0.09, respectively. The mass concentrations of TNF-α in genioglossus in the control group, OSAHS group and MAD group were (0.065±0.020), (0.097±0.018) and (0.071±0.020) µg/L, respectively. The mass concentrations of IL-6 in genioglossus in the control group, OSAHS group and MAD group were (0.063±0.013), (0.093±0.017), and (0.069±0.014) µg/L, respectively. For the above indicators, the data in OSAHS group were all significantly higher than that in MAD group and the control group (P<0.05). No significant difference was found between MAD group and the control group (P>0.05). Conclusions: Treatment of OSAHS with MAD decreased the mass concentration of TNF-α and IL-6 leading to fatigue of genioglossus, reduced the activation of NF-κB and played a significant role in protecting genioglossus.

Navigation-guided gap arthroplasty in the treatment of temporomandibular joint ankylosis.

Gap arthroplasty, used in the treatment of temporomandibular joint (TMJ) ankylosis, is challenging, requiring resecting of massive abnormal bone formation at the skull base with complex and distorted anatomy. This study evaluated the application of image-guided navigation to gap arthroplasty. Four gap arthroplasties were performed on patients with unilateral TMJ ankylosis under computer-assisted navigation guidance. After preoperative planning and 3-dimensional simulation, the normal anatomic structures of the TMJ were created by superimposing and comparing the unaffected and affected sides. The amount and range of ankylotic bone to be resected was determined and displayed. Registration achieved an accurate match between the intra-operative anatomy and the CT virtual images. Anatomic structures and the position of surgical instruments were shown real time on the screen. In all cases the accuracy of the system measured by the computer did not exceed 1mm. No complications occurred and the mean minimal thickness of the skull base between middle cranial fossa and reconstructed glenoid fossa was 1.97 mm. Using image-guided navigation resulted in safe surgical excision of the bony ankylosis from the skull base. Navigation-guided resection of the ankylotic bone in the TMJ gap arthroplasty was a valuable and safe technique in this potentially complicated procedure.

[Experimental study on osteoinduction of coral composited artificial bone].

OBJECTIVE: To improve the osteoinduction of coral and provide a perfect bone graft substitute for clinical bone defects. METHODS: By combining coral with collagen and recombinant human bone morphogenetic protein-2(rhBMP-2), coral/collagen/rhBMP-2 composite was obtained. The composite was implanted into the back muscle pouches of mice, and coral/collagen or coral/rhBMP-2 were implanted as control. The osteoinduction of the composite was assessed by histology and image analysis system. RESULTS: The chondrocyte differentiation and matrix formation were observed in local sites after one week, lamellar bone with bone marrow were formed after 4 weeks, and coral were absorbed partially. The quantity of osteoinduction was time-related and rhBMP-2 dose-related(P < 0.01). Coral/collagen and coral/rhBMP-2 implants did not show any bone or cartilage formation. CONCLUSION: The coral/collagen/rhBMP-2 composite possesses a superior osteoinduction and will be a new type of bone substitute to be used in orthopedic and maxillofacial surgery.