An injectable bioceramics-containing composite hydrogel promoting innervation for pulp-dentin complex repair

Abstract

Dental pulp-dentin complex defects remain a major unresolved problem in oral medicines. Clinical therapeutic methods including root canal therapy and vital pulp therapy are both considered as conservative strategies, which are incapable of repairing the pulp-dentin complex defects. Although biomaterial-based strategies show remarkable progress in antibacterial, anti-inflammatory, and pulp regeneration, the important modulatory effects of nerves within pulp cavity have been greatly overlooked, making it challenging to achieve functional pulp-dentin complex regeneration. In this study, we propose an injectable bioceramics-containing composite hydrogel in combination of Li-Ca-Si (LCS) bioceramics and gelatin methacrylate matrix with photo-crosslinking properties. Due to the sustained release of bioactive Li, Ca and Si ions from LCS, the composite hydrogels possess multiple functions of promoting the neurogenic differentiation of Schwann cells, odontogenic differentiation of dental pulp stem cells, and neurogenesis-odontogenesis couples in vitro. In addition, the in vivo results showed that LCS-containing composite hydrogel can significantly promote the pulp-dentin complex repair. More importantly, LCS bioceramics-containing composite hydrogel can induce the growth of nerve fibers, leading to the re-innervation of pulp tissues. Taken together, the study suggests that LCS bioceramics can induce the innervation of pulp-dentin complex repair, offering a referable strategy of designing multifunctional filling materials for functional periodontal tissue regeneration.

References

[1] ChangB, AhujaN, MaC, LiuX. Injectable scaffolds: Preparation and application in dental and craniofacial regeneration. Mater. Sci. Eng. R. Rep., 2017, 111: 1-26.

[2] ChenH, et al.. Regeneration of pulpo-dentinal-like complex by a group of unique multipotent CD24a⁺ stem cells. Sci. Adv., 2020, 61514.

[3] GallerKM, WeberM, KorkmazY, WidbillerM, FeuererM. Inflammatory response mechanisms of the Dentine-pulp complex and the periapical tissues. Int J. Mol. Sci., 2021, 221480.

[4] NakashimaM. Bone morphogenetic proteins in dentin regeneration for potential use in endodontic therapy. Cytokine Growth Factor Rev., 2005, 16: 369-376.

[5] SiddiquiZ, et al.. Cells and material-based strategies for regenerative endodontics. Bioact. Mater., 2022, 14: 234-249

[6] WangD, et al.. Schwann cell-derived EVs facilitate dental pulp regeneration through endogenous stem cell recruitment via SDF-1/CXCR4 axis. Acta Biomater., 2022, 140: 610-624.

[7] WeiY, et al.. Neural regeneration in regenerative endodontic treatment: an overview and current trends. Int J. Mol. Sci., 2022, 2315492.

[8] ZhengL, et al.. Injectable decellularized dental pulp matrix-functionalized hydrogel microspheres for endodontic regeneration. Acta Biomater., 2023, 156: 37-48.

[9] OrtiV, et al.. Pulp regeneration concepts for nonvital teeth: from tissue engineering to clinical approaches. Tissue Eng. Part B Rev., 2018, 24: 419-442.

[10] LiangC, et al.. Bone morphogenetic protein 7 mediates stem cells migration and angiogenesis: therapeutic potential for endogenous pulp regeneration. Int J. Oral. Sci., 2022, 1438.

[11] QianY, et al.. DLP printed hDPSC-loaded GelMA microsphere regenerates dental pulp and repairs spinal cord. Biomaterials, 2023, 299. 122137

[12] WaltonRE, Ramachandran NairPN. Neural elements in dental pulp and dentin. Oral. Surg. Oral. Med. Oral. Pathol. Oral. Radio. Endod., 1995, 80: 710-719.

[13] Hashemi-BeniB, KhoroushiM, ForoughiMR, KarbasiS, KhademiAA. Tissue engineering: Dentin - pulp complex regeneration approaches (A review). Tissue Cell, 2017, 49: 552-564.

[14] XuY, et al.. Inferior alveolar nerve transection disturbs innate immune responses and bone healing after tooth extraction. Ann. N. Y Acad. Sci., 2019, 1448: 52-64.

[15] LiuAQ, et al.. Sensory nerve-deficient microenvironment impairs tooth homeostasis by inducing apoptosis of dental pulp stem cells. Cell Prolif., 2020, 53. e12803

[16] LiZ, et al.. Schwann cells secrete extracellular vesicles to promote and maintain the proliferation and multipotency of hDPCs. Cell Prolif., 2017, 50. e12353

[17] FrostickSP, YinQ, KempGJ. Schwann cells, neurotrophic factors, and peripheral nerve regeneration. Microsurgery, 1998, 18: 397-405.

[18] LiangZ, et al.. Multifunctional Lithium-doped mesoporous nanoparticles for effective dentin regeneration in vivo. Int J. Nanomed., 2023, 18: 5309-5325.

[19] QiuY, et al.. SrCuSi₄O₁₀/GelMA composite hydrogel-mediated vital pulp therapy: integrating antibacterial property and enhanced pulp regeneration activity. Adv. Health Mater., 2023, 12. e2300546

[20] CooperPR, et al.. Inflammation–regeneration interplay in the dentine–pulp complex. J. Dent., 2010, 38: 687-697.

[21] NevesVCM, YianniV, SharpePT. Macrophage modulation of dental pulp stem cell activity during tertiary dentinogenesis. Sci. Rep., 2020, 10. 20216

[22] HilkensP, et al.. The angiogenic potential of DPSCs and SCAPs in an In vivo model of dental pulp regeneration. Stem Cells Int, 2017, 20172582080.

[23] WenB, et al.. Biomineralization-inspired mineralized hydrogel promotes the repair and regeneration of dentin/bone hard tissue. NPJ Regen. Med., 2023, 811.

[24] JinW, et al.. Biomimetic mineralized collagen scaffolds enhancing odontogenic differentiation of hDPSCs and dentin regeneration through modulating mechanical microenvironment. Chem. Eng. J., 2023, 460141800.

[25] DuanY, LiangY, YangF, MaY. Neural Regulations in tooth development and Tooth-Periodontium Complex Homeostasis: A literature review. Int J. Mol. Sci., 2022, 2314150.

[26] GaoC, et al.. Current progress in bioactive ceramic scaffolds for bone repair and regeneration. Int J. Mol. Sci., 2014, 15: 4714-4732.

[27] WenpingM, et al.. Hierarchically structured biomaterials for tissue regeneration. Microstructures, 2024, 42024014.

[28] GouY, QiK, WeiY, GuZ, XieH. Advances of calcium phosphate nanoceramics for the osteoinductive potential and mechanistic pathways in maxillofacial bone defect repair. Nano TransMed, 2024, 3100033.

[29] YangZ, et al.. 3D printing of sponge spicules-inspired flexible bioceramic-based scaffolds. Biofabrication, 2022, 14035009.

[30] DuL, et al.. Multicellular Bioprinting of Biomimetic Inks for Tendon-to-Bone Regeneration. Adv. Sci., 2023, 10. e2301309

[31] ZhengY, et al.. An ultralong hydroxyapatite nanowire aerogel for rapid hemostasis and wound healing. Chem. Eng. J., 2022, 430132912.

[32] ZhangH, et al.. Bioprinting of inorganic-biomaterial/neural-stem-cell constructs for multiple tissue regeneration and functional recovery. Natl. Sci. Rev., 2024, 11nwae035.

[33] ChenL, et al.. 3D printing of a lithium-calcium-silicate crystal bioscaffold with dual bioactivities for osteochondral interface reconstruction. Biomaterials, 2019, 196: 138-150.

[34] DuL, XueJ, HuanZ, WuC. Regulation of Tendon-bone related multiple cells by chemical ions released from Mo-containing Silicate Bioceramics. Acta Chim. Sin., 2023, 81: 1334-1340.

[35] QinC, et al.. 3D bioprinting of multicellular scaffolds for osteochondral regeneration. Mater. Today, 2021, 49: 68-84.

[36] YangM, et al.. Renal-friendly Li plus -doped carbonized polymer dots activate Schwann cell autophagy for promoting peripheral nerve regeneration. Acta Biomater., 2023, 159: 353-366.

[37] FarmaniAR, et al.. Li-doped bioactive ceramics: promising biomaterials for tissue engineering and regenerative medicine. J. Funct. Biomater., 2022, 13162.

[38] RybakowskiJK, SuwalskaA, HajekT. Clinical perspectives of lithium’s neuroprotective effect. Pharmacopsychiatry, 2018, 51: 194-199.

[39] KufflerDP. Can lithium enhance the extent of axon regeneration and neurological recovery following peripheral nerve trauma?. Neural Regen. Res, 2022, 17: 948-952.

[40] MakoukjiJ, et al.. Lithium enhances remyelination of peripheral nerves. Proc. Natl. Acad. Sci. USA, 2012, 109: 3973-3978.

[41] AliM, et al.. Lithium-containing surface pre-reacted glass fillers enhance hDPSC functions and induce reparative dentin formation in a rat pulp capping model through activation of Wnt/β-catenin signaling. Acta Biomater., 2019, 96: 594-604.

[42] WangJ, et al.. Progress on biomimetic mineralization and materials for hard tissue regeneration. ACS Biomater. Sci. Eng., 2023, 9: 1757-1773.

[43] HaoM, et al.. Hydroxyapatite nanorods function as safe and effective growth factors regulating neural differentiation and neuron development. Adv. Mater., 2021, 332100895.

[44] HeJ, et al.. Synergistic effect of endocellular calcium ion release and nanotopograpy of one-dimensional hydroxyapatite nanomaterials for accelerating neural stem cell differentiation. Compos Part B-Eng., 2021, 219108944.

[45] ZhangH, et al.. Calcium silicate nanowires-containing multicellular bioinks for 3D bioprinting of neural-bone constructs. Nano Today, 2022, 46. 101584

[46] MaY-X, et al.. Silicified collagen scaffold induces semaphorin 3A secretion by sensory nerves to improve in-situ bone regeneration. Bioact. Mater., 2022, 9: 475-490

[47] DengC, et al.. Bioactive scaffolds with Li and Si ions-synergistic effects for osteochondral defects regeneration. Appl. Mater. Today, 2018, 10: 203-216.

[48] OuyangL, ArmstrongJPK, ChenQ, LinY, StevensMM. Void-Free 3D bioprinting for in situ endothelialization and microfluidic perfusion. Adv. Funct. Mater., 2020, 301908349.

[49] SongW, SunW, ChenL, YuanZ. In vivo biocompatibility and bioactivity of calcium silicate-based bioceramics in endodontics. Front Bioeng. Biotechnol., 2020, 8580954.

[50] LinYT, et al.. The development of light-curable calcium-silicate-containing composites used in odontogenic regeneration. Polymers, 2020, 133107.

[51] HeJ, et al.. Gelatin methacryloyl hydrogel, from standardization, performance, to biomedical application. Adv. Health Mater., 2023, 12. e2300395

[52] AtilaDT, et al.. In vitro evaluation of injectable Tideglusib-loaded hyaluronic acid hydrogels incorporated with Rg1-loaded chitosan microspheres for vital pulp regeneration. Carbohydr. Polym., 2022, 278118976.

[53] LiuXY, DingCX, ChuPK. Mechanism of apatite formation on wollastonite coatings in simulated body fluids. Biomaterials, 2004, 25: 1755-1761.

[54] WuCT, ChangJ. Silicate bioceramics for bone tissue regeneration. J. Inorg. Mater., 2013, 28: 29-39.

[55] WeiR, ZhangZ, XingM, ZhouY, ChangJ. Preparation and in vitro evaluation of Lithium-doped bioactive glasses for wound healing with nerve repair potential. Mater. Lett., 2021, 292129629.

[56] GuX-K, LiX-R, LuM-L, XuH. Lithium promotes proliferation and suppresses migration of Schwann cells. Neural Regen. Res, 2020, 15: 1955-1961.

[57] NiuLN, et al.. Biomimetic remineralization of dentin. Dent. Mater., 2014, 30: 77-96.

[58] ZhangW, et al.. The performance of human dental pulp stem cells on different three-dimensional scaffold materials. Biomaterials, 2006, 27: 5658-5668.

[59] ZhangQ, et al.. Lithium-calcium-silicate bioceramics stimulating cementogenic/osteogenic differentiation of periodontal ligament cells and periodontal regeneration. Appl. Mater. Today, 2019, 16: 375-387.

[60] QinC, et al.. Cell-laden scaffolds for vascular-innervated bone regeneration. Adv. Health Mater., 2023, 12. e2201923

[61] MaW, et al.. A bioactive calcium silicate nanowire-containing hydrogel for organoid formation and functionalization. Mater. Horiz., 2024, 11: 2957-2973.

[62] HuangJ, et al.. An injectable hyaluronic acid/lithium calcium silicate soft tissue filler with vascularization and collagen regeneration. Bioact. Mater., 2024, 44: 256-268

[63] MizunoN, et al.. Effect of neurotrophins on differentiation, calcification and proliferation in cultures of human pulp cells. Cell Biol. Int, 2007, 31: 1462-1469.

[64] EramoS, et al.. Dental pulp regeneration via cell homing. Int Endod. J., 2018, 51: 405-419.

[65] MinQ, et al.. Immunomodulatory mechanism and potential application of dental pulp-derived stem cells in immune-mediated diseases. Int J. Mol. Sci., 2023, 248068.

Funding

National Natural Science Foundation of China (National Science Foundation of China)(52272284,32225028)

National Key R&D Program of China (2022YFC2405904) Joint Research Unit Plan of Chinese Academy of Sciences (121631ZYLH20240014) the Science and Technology Commission of Shanghai Municipality (24520750100).

RIGHTS & PERMISSIONS

The Author(s)