RESUMO
This study aimed to investigate correlation between mitochondrial reactive oxygen species and Porphyromonas gingivalis in the process of cementoblast pyroptosis. Lactate dehydrogenase activity assay, enzyme-linked immunosorbent assay, western blotting and flow cytometry analysis were utilized to explore whether Porphyromonas gingivalis triggered pyroptosis in cementoblasts. Reactive oxygen species and mitochondrial reactive oxygen species were detected using flow cytometry and fluorescence staining. The effect of mitochondrial reactive oxygen species on the Porphyromonas gingivalis-induced pyroptosis of cementoblasts was assessed by Mito-Tempo, mitochondrion-targeted superoxide dismutase mimetic. Phosphorylation levels of p65 were measured by western blotting. SC75741, a nuclear factor-kappa B inhibitor, was added to block the nuclear factor-kappa B in the Porphyromonas gingivalis-infected cementoblasts. Porphyromonas gingivalis triggered pyroptosis of cementoblasts, and an elevation in reactive oxygen species generation in the mitochondria was observed. Inhibition of mitochondrial reactive oxygen species reduced pyroptosis and nuclear factor-kappa B signaling pathway mediated the pyroptotic cell death in Porphyromonas gingivalis-infected cementoblasts. Together, our findings demonstrate that mitochondrial reactive oxygen species increased by Porphyromonas gingivalis participated in the pyroptosis of cementoblasts. Targeting mitochondrial reactive oxygen species may offer therapeutic strategies for root surface remodeling or periodontal regeneration.
RESUMO
BACKGROUND: This study aimed to investigate the potential associations between alveolar bone thickness, bucco-palatal inclination of maxillary lateral incisors, and lateral incisor root resorption in patients with unilateral maxillary impacted canines (UMICs). METHODS: A total of three hundred and five subjects (120 males, 185 females; mean age, 16.39 years; standard deviation, 4.04) with UMICs were included. Canine position and root resorption were assessed using CBCT. UMICs were divided into palatal, buccal and mid-alveolus groups (PICs, BICs and MAICs), with 117, 137 and 51 subjects, respectively. Alveolar bone thickness and bucco-palatal inclination of lateral incisors were measured using the Dolphin software. RESULTS: The prevalence of lateral incisor root resorption was significantly lower in the BICs (13.9%) than MAICs (29.4%) and PICs (29.1%). Alveolar bone thickness of the apical area was smaller in UMICs with lateral incisor root resorption than no resorption in both PICs (8.33 ± 1.64 vs 10.53 ± 2.55 mm) and BICs (8.94 ± 1.85 vs 10.76 ± 2.28 mm). Furthermore, lateral incisors on the impacted side were more buccally inclined in PICs with lateral incisor root resorption than no resorption, while in both BICs and MAICs, there was no statistical difference between lateral incisor root resorption than no resorption. Moreover, alveolar bone thickness of the apical area, rather than bucco-palatal inclination of lateral incisors, was significantly correlated with lateral incisor root resorption both in PICs and BICs. CONCLUSIONS: Lateral incisor root resorption is less common in BICs. Thinner alveolar bone thickness at the apical area of lateral incisors can be considered as a potential risk factor for lateral incisor root resorption in UMICs.