A theranostic dental pulp capping agent with improved MRI and CT contrast and biological properties

• Published in: Acta biomaterialia 2017-10, Vol.62, p.340-351
• Main Authors: Mastrogiacomo, S., Güvener, N., Dou, W., Alghamdi, H.S., Camargo, W.A., Cremers, J.G.O., Borm, P.J.A., Heerschap, A., Oosterwijk, E., Jansen, J.A., Walboomers, X.F.
• Format: Article
• Language: English
• Subjects: Acrylic Resins - chemistry; Acrylic Resins - pharmacokinetics; Acrylic Resins - pharmacology; Animals; Biological materials; Biological properties; BMP-2 (bone morphogenetic protein-2); Bone morphogenetic protein 2; Bone Morphogenetic Protein 2 - chemistry; Bone Morphogenetic Protein 2 - pharmacokinetics; Bone Morphogenetic Protein 2 - pharmacology; Calcium; Calcium phosphates; Capping; Chemical compounds; Composite materials; Composite Resins - chemistry; Composite Resins - pharmacokinetics; Composite Resins - pharmacology; Compressive strength; Computed tomography; Contrast Media - chemistry; Contrast Media - pharmacokinetics; Contrast Media - pharmacology; CPC (calcium phosphate cement); DCA (dual contrast agent); Dental care; Dental materials; Dental pulp; Dental pulp capping; Dental restorative materials; Dentin; Diagnostic agents; Diagnostic systems; Direct pulp capping; Ferric Compounds - chemistry; Ferric Compounds - pharmacokinetics; Ferric Compounds - pharmacology; Goats; Gold; Gold Colloid - chemistry; Gold Colloid - pharmacokinetics; Gold Colloid - pharmacology; Humans; Imaging; Incisor - diagnostic imaging; Incisor - metabolism; Incisor - surgery; Incisors; Injectability; Iron oxides; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Mechanical properties; MRI (magnetic resonance imaging); Particulate composites; Pharmacology; Phosphates; Polyurethanes - chemistry; Polyurethanes - pharmacokinetics; Polyurethanes - pharmacology; Pulp Capping and Pulpectomy Agents - chemistry; Pulp Capping and Pulpectomy Agents - pharmacokinetics; Pulp Capping and Pulpectomy Agents - pharmacology; Theranostic Nanomedicine - methods; Time compression; Tomography, X-Ray Computed - methods
• ISSN: 1742-7061; 1878-7568
• DOI: 10.1016/j.actbio.2017.08.018

[Display omitted] Different materials have been used for vital dental pulp treatment. Preferably a pulp capping agent should show appropriate biological performance, excellent handling properties, and a good imaging contrast. These features can be delivered into a single material through the combination of therapeutic and diagnostic agents (i.e. theranostic). Calcium phosphate based composites (CPCs) are potentially ideal candidate for pulp treatment, although poor imaging contrast and poor dentino-inductive properties are limiting their clinical use. In this study, a theranostic dental pulp capping agent was developed. First, imaging properties of the CPC were improved by using a core–shell structured dual contrast agent (csDCA) consisting of superparamagnetic iron oxide (SPIO) and colloidal gold, as MRI and CT contrast agent respectively. Second, biological properties were implemented by using a dentinogenic factor (i.e. bone morphogenetic protein 2, BMP-2). The obtained CPC/csDCA/BMP-2 composite was tested in vivo, as direct pulp capping agent, in a male Habsi goat incisor model. Our outcomes showed no relevant alteration of the handling and mechanical properties (e.g. setting time, injectability, and compressive strength) by the incorporation of csDCA particles. In vivo results proved MRI contrast enhancement up to 7weeks. Incisors treated with BMP-2 showed improved tertiary dentin deposition as well as faster cement degradation as measured by µCT assessment. In conclusion, the presented theranostic agent matches the imaging and regenerative requirements for pulp capping applications. In this study, we combined diagnostic and therapeutic agents in order to developed a theranostic pulp capping agent with enhanced MRI and CT contrast and improved dentin regeneration ability. In our study we cover all the steps from material preparation, mechanical and in vitro characterization, to in vivo study in a goat dental model. To the best of our knowledge, this is the first time that a theranostic pulp capping material have been developed and tested in an in vivo animal model. Our promising results in term of imaging contrast enhancement and of induction of new dentin formation, open a new scenario in the development of innovative dental materials.