Dental, oral, and craniofacial (DOC) regenerative medicine aims to repair or regenerate DOC tissues including teeth, dental pulp, periodontal tissues, salivary gland, temporomandibular joint (TMJ), hard (bone, cartilage), and soft (muscle, nerve, skin) tissues of the craniofacial complex. Polymeric materials have a broad range of applications in biomedical engineering and regenerative medicine functioning as tissue engineering scaffolds, carriers for cell-based therapies, and biomedical devices for delivery of drugs and biologics. The focus of this review is to discuss the properties and clinical indications of polymeric scaffold materials and extracellular matrix technologies for DOC regenerative medicine. More specifically, this review outlines the key properties, advantages and drawbacks of natural polymers including alginate, cellulose, chitosan, silk, collagen, gelatin, fibrin, laminin, decellularized extracellular matrix, and hyaluronic acid, as well as synthetic polymers including polylactic acid (PLA), polyglycolic acid (PGA), polycaprolactone (PCL), poly (ethylene glycol) (PEG), and Zwitterionic polymers. This review highlights key clinical applications of polymeric scaffolding materials to repair and/or regenerate various DOC tissues. Particularly, polymeric materials used in clinical procedures are discussed including alveolar ridge preservation, vertical and horizontal ridge augmentation, maxillary sinus augmentation, TMJ reconstruction, periodontal regeneration, periodontal/peri-implant plastic surgery, regenerative endodontics. In addition, polymeric scaffolds application in whole tooth and salivary gland regeneration are discussed.

Poly(3-hexylthiophene)/graphene (P3HT/G) materials are synthesized using an in situ Grignard metathesis approach. The structural properties and spectroscopy of the materials are studied using NMR, FTIR, and UV-vis absorption spectroscopies, wide-angle X-ray scattering, atomic force microscopy and cyclic voltammetry. P3HT regioregularities !90% are observed in composites with approximate graphene compositions as high as 20% by weight. 1 H and 13 C NMR spectra of liquid phase dispersions reveal signals that are not observed in pristine P3HT. The intensity of these signals correlates with the graphene content, thereby indicating that the graphene is influencing the polymerization process. Anomalous features in the FTIR spectra of P3HT/G powders are also observed. AFM images of P3HT/G films show morphological differences between P3HT on graphene compared with P3HT domains on the silicon substrates. Cyclic voltammetry reveals a monotonic decrease in the energy of the HOMO and LUMO levels of P3HT with increasing graphene loading.

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The improvement of cellulosic biomass-polymer composites needs to evaluate what occurs at the biomass-matrix interface during crystallization. Different well-defined maize tissues were obtained by original dry fractionation processes, without chemical treatment. Their morphological features were identified by optical and scanning electron microscopies. For each type of tissue, a small fragment was sandwiched between two films of isotactic polypropylene. The composite was subjected to quiescent isothermal conditions, followed in-situ by polarized optical microscopy. Focus of the heterogeneous nucleation at the surface of maize tissues showed that in all cases, more or less numerous semi-crystalline entities originated from the tissue surface, indicating a moderate nucleating activity. Different crystallization behaviors were observed as a function of the tissue. Growth rates of surface layers were generally higher that the growth rates of bulk spherulites. The differences were small, but significant. They were discussed within the frame of kinetic theory of growth.