Oral health is an integrated part of the public wellbeing, and does not only affect the qualityof life, but also the healthcare system through related economic costs. Despite great global progressin oral health related issues, dental caries is still a major problem that affects both children andadults. Indeed, dental restorative work in industrialized countries is very costly, thus developing andimproving restorative materials can beneficially impact the public health system. Among dentalrestorative materials glass ionomer cements (GIC) are of great interest, since they have the ability tobond to the tooth structure without the need for preconditioning the surface with an acid orunnecessary removal of tooth substance. Furthermore, fluoride is slowly released during settingadding to the anticariogenic benefits of the material. GIC’s poor mechanical strength is however adisadvantage, and improved knowledge on this subject can bring potential development. Onepossibility is to advance our understanding of the dynamics of the aqueous solution used to preparethe GIC.Under these lines, in this work I have combined neutron spectroscopy and calorimetricanalysis to understand the nanoscale mobility of the hydrogen atoms, mostly from water, present inconventional GIC. Water plays a big part in the setting process in GIC. It is the reaction medium inwhich the cations leach to crosslink. Furthermore, water also hydrates the siliceous hydrogel and themetal polyacrylate salts. In matured GIC, water occupies coordination sites around cations in ahydration shell of the cation-polyacrylate, hydration regions around the polymer chain or stillremains unbound in its bulk state. Neutron spectroscopy was chosen since the high incoherentscattering cross section of the hydrogen atom makes this technique ideal for assessing the dynamicsof water in the material. Water is furthermore also easily detected by thermogravimetric analysiscoupled to Fourier transform infrared spectroscopy and differential scanning calorimetric methods,which were also employed in this thesis. However understanding water dynamics in such complexhierarchical structure, where different motions occur in a broad range of time scales andsimultaneously, can be difficult. So in this Ph.D. thesis, the experimental data was combined withpreliminary classical molecular dynamics simulations (MD), aiming to investigate the differentnanoscale water dynamics in the GIC. This unique approach opens new possibilities to betterexplore all the information contained in the neutron spectroscopy data.Selected materials were investigated by first understanding the molecular motions of thedifferent aqueous polyacrylic acid solutions (PAA) that are used in preparing the cements. Theseresults are reported in Paper 1 and Paper 2. These findings were afterwards superimposed to theGICs themselves, in order to separate distinct molecular motions. This approach shows that thestructure of the PAA solutions influences the overall properties of the GIC. The investigation of thedynamics of the confined liquid, the main body of this thesis, is reported in Paper 2. The resultsshow that water is confined differently in the polymer chain depending on the GIC. Two subprojects involving GIC that are not yet in a manuscript form are also briefly described in Chapter 3.These results further confirm that how the water is confined in the polymer chain determines itsbehavior in the GIC and to a certain extent controls hydrogen binding to the GIC structure.Therefore, the knowledge acquired during this Ph.D. thesis contributes to the understanding of thenature of the hydration in the GIC and can be applied towards the development and improvement ofdental restorative materials.Furthermore, two manuscripts regarding water and protein dynamics in confinement probedby quasi-elastic neutron scattering are also included in the thesis, Paper 3 and Paper 4. In Paper 3we investigated why two chalk samples display vastly different water uptake, despite the fact thatthey are known to have similar pore volumes. In Paper 4 we investigated the dynamics ofencapsulated Hepatitis B surface antigen in mesoporous silica SBA-15. My knowledge of liquids inconfinement was extended by the analysis of the neutron data on these new and challengingsystems.