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


STATEMENT OF SIGNIFICANCE
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.
['Mastrogiacomo|S|S|', 'Güvener|N|N|', 'Dou|W|W|', 'Alghamdi|H S|HS|', 'Camargo|W A|WA|', 'Cremers|J G O|JGO|', 'Borm|P J A|PJA|', 'Heerschap|A|A|', 'Oosterwijk|E|E|', 'Jansen|J A|JA|', 'Walboomers|X F|XF|']
D000180:Acrylic Resins D000818:Animals D055396:Bone Morphogenetic Protein 2 D003188:Composite Resins D003287:Contrast Media D005290:Ferric Compounds D006041:Goats D017979:Gold Colloid D006801:Humans D007180:Incisor D008279:Magnetic Resonance Imaging D011140:Polyurethanes D057872:Pulp Capping and Pulpectomy Agents D000068936:Theranostic Nanomedicine D014057:Tomography, X-Ray Computed
Direct pulp capping BMP-2 (bone morphogenetic protein-2) CPC (calcium phosphate cement) DCA (dual contrast agent) MRI (magnetic resonance imaging)