rhBMP-2/ACS significantly enhances GBR at turned and surface-etched dental implants. The dental implant surface technology does not appear to substantially influence bone formation.

Background: Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) technologies have been shown to significantly support alveolar bone formation. Biomaterial limitations, however, have restricted the biologic potential for onlay indications. The objective of this study was to evaluate regeneration of alveolar bone and periodontal attachment, and biomaterials reaction following surgical implantation of a spaceproviding, bioabsorbable, macroporous, polyglycolic acid‐trimethylene carbonate (PGA‐TMC) membrane combined with a rhBMP‐2 construct in a discriminating onlay defect model.Methods: Routine supraalveolar periodontal defects were created at the mandibular premolar teeth in 9 beagle dogs. Contralateral jaw quadrants in subsequent animals were randomly assigned to receive the domeshaped PGA‐TMC (100 to 120 μm pores) membrane with rhBMP‐2 (0.2 mg/mL) in a bioresorbable hyaluronan (Hy) carrier or the PGA‐TMC membrane with Hy alone (control). The gingival flaps were advanced to submerge the membranes and teeth and sutured. Animals were euthanized at 8 and 24 weeks postsurgery for histologic observations.Results: Jaw quadrants receiving the PGA‐TMC membrane alone experienced exposures at various time points throughout the study. Jaw quadrants receiving the PGA‐TMC/rhBMP‐2 combination remained intact, although one site experienced a late minor exposure. Newly formed alveolar bone approached and became incorporated into the macroporous PGA‐TMC membrane in sites receiving rhBMP‐2. The PGA‐TMC biomaterial was occasionally associated with a limited inflammatory reaction. Residual PGA‐TMC could not be observed at 24 weeks postsurgery. Residual Hy could not be observed at any time interval. Regeneration of alveolar bone height (means ± SD) was significantly increased in sites receiving the PGA‐TMC/rhBMP 2 combination compared to control (3.8 ± 1.3 versus 0.7 ± 0.5 mm at 8 weeks and 4.6 ± 0.8 versus 2.1 ± 0.4 mm at 24 weeks; P <0.05). Limited cementum regeneration was observed for PGA‐TMC/rhBMP‐2 and PGA‐TMC control sites. Ankylosis compromised regeneration in sites receiving PGA‐TMC/rhBMP‐2.Conclusions: The bioabsorbable, space‐providing, macroporous PGA‐TMC membrane appears to be compatible biomaterial for bone augmentation procedures. rhBMP‐2 significantly enhances alveolar bone augmentation and soft tissue healing when combined with the PGA‐TMC membrane. J Periodontol 2003; 74:635‐647.

The design of biomaterials containing specific ligands on the surface offers the possibility of creating materials that can interact with and potentially control mammalian cell behavior. Biodegradable materials further provide the significant advantage that the polymer will disappear in vivo, obviating long-term negative tissue responses as well as the need for retrieval. In earlier studies we synthesized and characterized arginine-glycine-aspartic acid (RGD) peptide-modified poly(lactic acid-co-lysine) (PLAL). In this study, both bulk properties and surface features have been characterized, with a focus on surface analysis as a means of interpreting observed changes in cell behavior. Bulk peptide attachments were performed using 1,1Ј-carbonyldiimidazole (CDI). Amino groups were measured using colorimetric assays and X-ray photoelectron spectroscopy (XPS). Peptides were measured by incorporating iodine into the peptide as a distinct elemental marker for use with XPS. Typical samples contained 13 ± 4 pmol/cm 2 of amino groups and 4 ± 0.2 pmol/ cm 2 of peptides, as calculated from XPS measurements of nitrogen and iodine. The wettability and crystallinity of the samples were determined by contact angles and differential scanning calorimetry, respectively. Wettability and crystallinity were not altered by the incorporation of lysine or peptides. After incubating bovine aortic endothelial (BAE) cells for 4 h on surfaces with RGD-containing peptides, the mean spread cell area increased from 77 ± 2 m 2 to 405 ± 29 m 2 compared to 116 ± 11 m 2 on poly(lactic acid), 87 ± 4 m 2 on PLAL, and 105 ± 4 m 2 on surfaces with RDG-containing (control) peptides. The significance of this work is that the first synthetic interactive, resorbable biomaterial has been developed, and use of this material to control cell behavior has been demonstrated.

We report a noncytotoxic resin compatible with and designed for use in custom high-resolution 3D printers that follow the design approach described in Gong et al., Lab Chip 17, 2899 (2017). The noncytotoxic resin is based on a poly­(ethylene glycol) diacrylate (PEGDA) monomer with avobenzone as the UV absorber instead of 2-nitrophenyl phenyl sulfide (NPS). Both NPS-PEGDA and avobenzone-PEGDA (A-PEGDA) resins were evaluated for cytotoxicity and cell adhesion. We show that NPS-PEGDA can be made effectively noncytotoxic with a postprint 12 h ethanol wash, and that A-PEGDA, as-printed, is effectively noncytotoxic. 3D prints made with either resin do not support strong cell adhesion in their as-printed state; however, cell adhesion increases dramatically with a short plasma treatment. Using A-PEGDA, we demonstrate spheroid formation in ultralow adhesion 3D printed wells, and cell migration from spheroids on plasma-treated adherent surfaces. Given that A-PEGDA can be 3D printed with high resolution, it has significant promise for a wide variety of cell-based applications using 3D printed microfluidic structures.

The data from this study suggest that a space-providing macroporous ePTFE device defines rhBMP-2/ACS-induced alveolar augmentation to provide adequate bone quantities for implant dentistry. The dental implant surface technology does not appear to substantially influence bone formation.