SEM Observation of Composite Ceramic Scaffolds’ Surface during Incubation in Culture Medium with or without Human PDL Fibroblasts

Abstract

Chitin is a polysaccharide abundant in nature. Its’ deacetylation product-chitosan- in combination with gelatin (collagen product) is commonly used asbiopolymer scaffold for tissue engineering. The aim of this study was to investigate diffrerences in surface characteristics of chitin (CHN CCS) and chitosan –gelatin (CHS-G CCS) composite ceramic scaffolds (CCS), during their incubation in culture medium (DMEM) with or without human periodontal ligament fibroblasts (HPDLF). CHN CCS and CHS- G CCS, with pore size 70-200μm, were fabricated on the surface of ceramic disks, being coated with a mixture of bioactive glass – ceramic (1:1 wt). Three CCSs of each type were constructed. Each CCS was incubated at 37 °C up to 10 days, either only in DMEM supplemented with 10% FCS or in DMEM with the presence of 105HPDLF. SEM microphotographs and EDS analysis, before and after incubation, were used to investigate CCSs’ surface alterations. Before incubation, all type of CCSs appeared to be macro porous with high interconnectivity. Exposed to incubation, CHN CCSs’ surface porosity seemed to be rapidly reduced and a rough surface without pores was observed with or without HPDLF. Attached HPDLF were rarely detected. CHS-G CCSs appeared to retain surface porosity in DMEM without cells. In HPDLF culture an almost uniform surface with organic aggregates and attached cells was observed. Until day 10, HPDLF could only be detected at CHS-G CCS’s surface. Conclusion: SEM microphotographs observations indicate that CHN CCSs’ incubation in DMEM led in early and rapid coalescence of surface pores, thus inhibiting HPDLF attachment. HPDLF attachment on CHS-G CCSs confirm the beneficial role of gelatin, while differences in CHS-G CCSs’ surface with and without HPDLF culture indicate that not only sedimentation of medium's ingredients, but cell attachment and function could decrease surface’s porosity, affecting consequently HPDLF proliferation.