[A PhD completed. Carbon dots and their applications in oral health].

Nanocarbon particles, or carbon dots, are amorphous carbon structures less than 10nm in size. Due to their unique properties, carbon dots have been investigated for various medical applications. In this dissertation research, we synthesized carbon dots from different sources, and characterized their chemical and toxic properties both in vitro and in vivo. In addition, a few potential applications of carbon dots in oral health were investigated, including a mouse model for Sj gren s syndrome. This showed that carbon dots were able to modulate the mouse s immune system, leading to a milder autoimmune response compared to that of untreated mice. Furthermore, the effects of other carbon dots on acid-induced demineralization of hydroxyapatite were investigated in vitro. These carbon dots, in combination with phytosphingosine, reduced calcium release from hydroxyapatite slices exposed to acid by 26% compared to the control group. This indicates that carbon dots promote the binding of phytosphingosine to hydroxyapatite, thereby enhancing the protective effect of phytosphingosine.