Method: In the 1st-series of experiments dentin was divided into 2-groups. Group-1-dentin was fully demineralized to create natural collagen scaffolds, whereas group-2-dentin was assigned as the control. Dentin of both groups was infiltrated with a colloidal solution of silver nanoparticles and examined by SEM/EDX.
In the 2nd-series of experiments dentin was also divided into 2-groups. Dentin-of-group-1 was assigned as the control. Remaining group-2-samples were immersed into ethanol. All samples were then tested using SEM/EDX. Alicona-MeX3D, SolidWorks and Delcam-PowerShape-software along with a 3D-printer Object-Eden-350V were used to generate 3D –models of the observed crystals and produce their prototypes. A single-crystal-X-ray-diffractometer XCalibur/Gemini-A was selected for crystal structural analysis.
Result: In the course of laboratory experiments it was revealed that Ag-nanoparticles penetrated not only into dentinal tubules but intertubular collagen fibers. The latter could be explained by the fact that demineralization leads to structural changes in dentine surface, it is getting smoother at the macro - level but bigger at the micro-level. Dentine surface developing, raising of its area and adsorption capacity make Ag-infiltration into dentine easier.
Laboratory experiments demonstrated self-induced crystal formation on dentine surface that had been exposed ethanol. Chemical nature of the structures was identiified and possible physical mechanisms of crystal growth were discussed.
Conclusion: 1)The results of laboratory experiments point out to the feasibility to infiltrate the collagen matrix of demineralized dentin by nanosized particles. Research findings clearly show that collagen matrix could be considered as a scaffold for mineral substance delivery; 2)Research findings demonstrate the possibility of self-induced calcium-phosphate crystal formation on dentine surface, which could be considered as a path to in vivo hard tooth tissue regeneration.