ABSTRACT
Objective@# To investigate the effect of cobalt (Co) and calcium-phosphate (Ca/P) doped coating on titanium surfaces and their angiogenic effect.@*Methods @# Microarc oxidation (MAO) was used to prepare Co-Ca/P-doped and Co-doped coatings. Titanium (Ti) sheet without MAO treatment was used as control. Scanning electron microscopy (SEM) was used to observe the surface micromorphology of the coatings. Energy dispersive spectrometry (EDS) was also applied to detect the doped chemicals and their contents. Standard soaking solutions of these coatings were prepared using an endothelial cell medium (ECM) solution for subsequent angiogenesis experiments. Human umbilical vein endothelial cells (HUVECs) were cultured on Matrigel with ECM soaking solutions for 4 h and 8 h. The microvessels were observed under a microscope, and the number of microtubules and their interconnecting nodes were analyzed with Image J software. @*Results@# Co doped and Co-Ca/P-doped coatings were successfully prepared by MAO, which was demonstrated by both SEM observation and EDS analysis. SEM observation showed that irregular crystals of the above chemicals were present on both Co and Co-Ca/P-doped coatings, commonly with a diameter <2 μm. However, more crystals were observed on the Co-Ca/P coatings than on the Co coating, and the distribution of the crystals was more homogenous on the Co-Ca/P coatings. However, only polishing scratches were observed on the Ti sample surface. EDS analysis indicated that in contrast to only Co in the Co coating, Co, Ca and P were doped within the Co-Ca/P coating, and none of the three elements were observed on the Ti plate surface. The number of vascular rings and nodes formed by HUVECs in the extract of the Co-Ca/P group was significantly higher than that of the Co group (P<0.05), and the angiogenic effect of these two components was significantly better than that of the Ti group (P<0.05). @*Conclusion@#The Co-Ca/P coating exhibits good angiogenic properties in vitro and is valuable for the development of new titanium implants with high surface bioactivity.
ABSTRACT
Objective @#To study the effect of anterior traction on the temporomandibular joint in adolescent patients with skeletal Class Ⅲ malocclusion.@*Methods@#Twenty-nine patients with early permanent dentition with skeletal class Ⅲ malocclusions were measured by cephalometry and a coordinate system before and after maxillary protraction. The correlation between dentofacial structures and the temporomandibular joint was analyzed. @*Results @# After maxillary protraction, cephalometric measurements showed that the dentofacial structure changed significantly; ANB increased by 3.97° ± 2.32° (P<0.001); U1-SN increased by 4.97° ± 5.51° (P<0.001); L1-MP decreased by 1.26° ± 1.41° (P = 0.008); and MP-SN increased by 1.02° ± 3.90° (P = 0.003). The coordinate system measurement showed that the S-Fpx was decreased by 0.16 ± 1.52 mm (P = 0.041), the S-Ciy distance was significantly decreased by 0.09 ± 2.03 mm (P = 0.028), and there was no significant change in the temporomandibular joint spaces (A, P, and C) (P>0.05). Correlation analysis showed a moderate negative correlation between the posterior margin of the temporomandibular joint fossa and U1-SN (r = -0.427, P = 0.042). There was a moderate positive correlation between the leading edge of the condyle and ANB (r = 0.425, P = 0.043); there was no correlation between the joint space and dentofacial changes. @* Conclusion@#After treatment with maxillary protraction for adolescent skeletal class Ⅲ malocclusion, maxillary protraction had some effect on changes in the temporomandibular joint fossa and condyle and had no effect on the joint space.