title: A novel injectable chitosan/polyglutamate polyelectrolyte complex hydrogel with hydroxyapatite for soft-tissue augmentation.
abstract: This study demonstrated a chitosan (CS)/polyglutamate (PG) polyelectrolyte complex (PEC) hydrogel combined with spherical hydroxyapatite (HAp) particles as an injectable dermal filler for soft-tissue augmentation. The CS/PG PEC hydrogel with oppositely charged ionic cross-linking, a high gel content, and low degradation rate was introduced as a carrier to achieve high shape and volume stability. An MTT assay indicated that the CS/PG PEC had satisfactory cell biocompatibility. This PEC/HAp hydrogel showed good structural integrity in a PBS solution for up to 60 days. Clinical manageability was indexed by an injection force measurement through sterile 27-gauge needles using a texture analyzer. In an animal study, 0.2 mL of the PEC and PEC/hydroxyapatite (HAp) were implanted within the dorsal dermis of a swine ear. Injected tissue areas were biopsied 2 weeks, and 2 and 6 months after the injection. According to the histomorphometric results, the PEC and PEC/HAp groups showed percentages of retention of the maximum height of the cross-section of about 44% and 73% at 6 months. New collagen was observed in the central position indicating a possible collagenesis effect. These results suggest that this PEC/HAp system can be used as an alternative for soft-tissue augmentation.
authors.affiliation: School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan, ROC.
authors.forename: Dian-Yu
authors.initials: DY
authors.lastname: Ji
authors.affiliation: School of Veterinary Medicine, National Taiwan University, Taipei 106, Taiwan, ROC.
authors.forename: Tzong-Fu
authors.initials: TF
authors.lastname: Kuo
authors.affiliation: School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan, ROC.
authors.forename: Hong-Da
authors.initials: HD
authors.lastname: Wu
authors.affiliation: School of Dental Technology, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan, ROC; Center for Teeth Bank and Dental Stem Cell Technology, Taipei Medical University, Taipei 110, Taiwan, ROC.
authors.forename: Jen-Chang
authors.initials: JC
authors.lastname: Yang
authors.affiliation: School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan, ROC; Center for Teeth Bank and Dental Stem Cell Technology, Taipei Medical University, Taipei 110, Taiwan, ROC; Dental Department of Taipei Medical University Municipal Wan-Fang Hospital, Taipei 116, Taiwan, ROC.
authors.forename: Shang-Yang
authors.initials: SY
authors.lastname: Lee
mesh_terms: D000818:Animals; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology; D003094:Collagen / Q000096:biosynthesis; D020405:Dermis / Q000378:metabolism* / Q000473:pathology; D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology; D020100:Hydrogels / Q000737:chemistry / Q000494:pharmacology; D008422:Materials Testing; D051379:Mice; D041681:NIH 3T3 Cells; D011099:Polyglutamic Acid / Q000737:chemistry / Q000494:pharmacology; D013552:Swine
chemical_list: D020100:Hydrogels; D011099:Polyglutamic Acid; D003094:Collagen; D048271:Chitosan; D017886:Durapatite