Dental pulp cells are naturally capable of forming reparative dentine in response to minor tooth damage. However, this effect is limited and cannot restore large defects. Here, we aim to investigate how endogenous cells can be stimulated to produce reparative dentin to fully repair large areas of damaged tissue and emphasize the use of Raman spectroscopy for the subsequent analysis and assessment of regenerated tooth. We have identified several compounds, which stimulate dental pulp cells to form neo-dentin via upregulation of Wnt/β-catenin signalling. These compounds were delivered using an injectable hydrogel system based on hyaluronic acid that can be solidified using a common dental blue light. Hydrogel properites were tuned to enable quick degradation and a burst release of the compound. Surgery was performed on anaesthesised rodents (mice and rats) by drilling a full size defect in both M1 molars of the upper jaw. Wnt-stimulating compounds dissolved in DMSO were mixed with hydrogel components. Controls utilised mineral trioxide aggregate (MTA), the current standard treatment, and hydrogel + DMSO or hydrogel only. Defects were filled with the appropriate material and sealed with glass ionomer cement. Animals were sacrificed after 4 weeks, the upper jaw isolated and teeth analysed by micro computed tomography (μCT) before being split in half to allow for Raman spectroscopy at the site of damage. Spectra were collected using 100mW 785nm laser excitation, 20s acquisition time, 3 accumulations and covered the fingerprint region (440-1800cm-1, ~3-5cm-1 resolution). In comparison to the control groups, tunable hydrogels enriched with Wnt/ β-catenin modulating drugs induced mineral formation at the site of damage as determined by μCT and Raman spectroscopy. Whereas μCT only reveals differences in material density Raman spectroscpy is capable of revealing the chemical composition. An univariate analysis of the peak position and full width half maximum of the mineral Raman band around 960cm-1 revealed no significant differences between regenerated dental tissue and normal tooth. Mineral/matrix ratios based on the areas of the mineral band at 960cm-1 and collagen specific proline, hydroxyproline bands around 855 and 875cm-1 also showed no significant difference between normal and regenerated tissue.
|Publikationsdato||22. okt. 2018|
|Status||Udgivet - 22. okt. 2018|
|Begivenhed||SciX 2018 - Atlanta, USA|
Varighed: 26. okt. 2018 → 26. okt. 2018
|Periode||26/10/2018 → 26/10/2018|