Unilateral nasal obstruction induces morphological changes of the mandibular condyle in growing rats

摘要: Abstract Purpose Chronic nasal obstruction is known to decrease blood oxygen saturation. Mouth breathing in association with chronic leads the collapse of buccinator mechanism and a clockwise rotation mandible, which causes mandibular retrusion. This study aimed investigate influences on morphological histological changes mandible growing rats. Materials methods Thirty 8-day-old male Wistar rats were randomly divided into control experimental groups. The group underwent unilateral by cauterization external nostrils at 8 days age. Pulse saturation (SpO2) was monitored every week. Rats sacrificed 9 weeks analyzed via lateral cephalometric radiographs micro-CT scans. We utilized toluidine blue tartrate-resistant acid phosphatase (TRAP) staining for analysis. Immunohistochemical hypoxia induced factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), osteoprotegerin (OPG) receptor activator nuclear kappa-B ligand (RANKL) also performed reveal changes. Results SpO2 significantly lower than group. In group, length, bone mineral density cartilage layer thickness condyle decreased. number TRAP-positive cells condyle, HIF-1α-positive cells, VEGF-positive RANKL-positive condylar increased. contrast, reduced expression OPG protein observed Conclusions Our findings suggest that period affects morphology.