ACE2 COVID-19 Korea Medicine NiTi alloy Portuguese population VAS (visual analog scale) scale age determination by teeth age estimation applied model applied sciences atomic force microscopy autoclave cardiovascular disease caries cephalometric analysis chronic periodontitis clear aligners cohort cone beam computed tomography corrosion cranial base craniofacial orthopedic cytokines dental measurements digital dentistry digital orthodontics endodontic sterilization endodontics facial skeleton