Differential impact of chronic intermittent hypoxia and stress changes on condylar development.

OBJECTIVES: This study aimed to determine the effects of chronic intermittent hypoxia (CIH) and stress change (SC) on the development of the condyle in mouth breathing rats. DESIGN: A total of 120 4-week-old rats were randomly assigned to one of five groups. The control (Ctrl) group was the blank control and the intermittent nasal obstruction (INO) group was the positive control. Mild CIH (mCIH) and severe CIH (sCIH) groups were developed by adjusting environmental oxygen concentration and monitoring real-time blood oxygen saturation (SpO2). The SC group was developed using INO, increased environmental oxygen concentration, and real-time SpO2 monitoring. Six rats from each group were sacrificed for analysis at 0, 1, 2, or 4 weeks. RESULTS: Similar to the INO group, condyle and mandibular body development in the sCIH group, but not in the mCIH group, was significantly inhibited compared with the Ctrl group. The SC group had inhibited development of the condyle, especially of the posterior zone, but had minimal impact on the growth of the mandible. CONCLUSION: The inhibitory effects of CIH on the development of the condyle and mandibular body were SpO2-dose-dependent. When SC occurred, inhibited development was observed in the posterior zone of condyle but not the whole mandible. These findings provide important insights for targeted interventions that address the consequences of mouth breathing in children.

Right ventricular outflow tract patch reconstruction in anomalous origin of right coronary artery.

A new technique to repair tetralogy of Fallot or double-outlet right ventricle with an anomalous right coronary artery arising from the left anterior descending coronary artery and crossing the right ventricular outflow tract is described. The right coronary artery was mobilized, transected, and re-implanted into the ascending aorta. The right ventricular outflow tract and ventricle septal defect were repaired through a ventriculotomy and pulmonary arteriotomy. The right ventricular outflow tract and pulmonary annulus were reconstructed with a pericardial patch. Five consecutive patients underwent this technique between August 2007 and October 2008. The indications of the electrocardiograms were no heart ischemia in all patients at mean follow-ups conducted at 5 to 19 months. All the patients were in New York Heart Association functional class I at the time of last follow-up.