Surface characteristics of three commercially available grafts and adhesion of stem cells to these grafts

Comparative evaluation of platelet-rich fibrin, platelet-rich fibrin + 50 wt% nanohydroxyapatite, platelet-rich fibrin + 50 wt% dentin chips on odontoblastic differentiation - An in vitro study-part 2

AIM

The purpose of this study was to investigate the effects of platelet-rich fibrin (PRF) modified with bioactive radiopacifiers-nanohydroxyapatite (nHA) and dentin chips (DC) on odontoblastic differentiation in human dental pulp cells (HDPCs).

SUBJECTS AND METHODS

PRF was modified with 50wt% of nHA (G bone-SHAG31, Surgiwear Company) and 50 wt% of DC. HDPSCs differentiation and mineralization by the groups ([Group A - Control (Dimethyl sulfoxide), Group B - PRF, Group C - PRF + nHA, Group D - PRF + DC]) were assessed. ELISA was done to quantify the interleukin (IL)-6 and IL-8 cytokine expression. The odontoblastic differentiation was determined by the expression of odontogenesis-related genes and the extent of mineralization using alizarin red S staining.

STATISTICAL ANALYSIS USED

One-way ANOVA with post hoc Tukey-honestly significant difference tests were applied to assess the significance among various groups.

RESULTS

The level of inflammatory cytokines (IL-6 and IL-8) expression by Group D (PRF + 50 wt% DC) was higher compared to Group B (PRF) and Group C (PRF + 50 wt% DC). Group C (PRF + 50 wt% nHA) induced more mineralization nodules compared to other groups. The integrated density value for the DSPP and DMP-1 protein expression by Group C (PRF + 50 wt% nHA) and Group D (PRF + 50 wt% DC) was higher compared to Group B (PRF).

CONCLUSIONS

The results suggest that the addition of bioactive radiopacifiers into PRF has a synergistic effect on the stimulation of odontoblastic differentiation of HDPCs, hence inducing mineralization.

Bone Xenografts in Trauma and Orthopaedics (Analytical Review)

Purpose of the analytical review — to evaluate the application experience of bone xenografts in trauma and orthopaedics surgery. Methods. Data search was performed in the electronic databases of PubMed and eLIBRARY with depth of 20 years. Results. The authors identified 13 papers which described the application experience of bone xenografts in trauma surgery and orthopaedics. The highest efficiency (from 92 to 100%) was reported for cases of xenografts use to replace defects in intraarticular fractures and revision arthroplasty. Unsatisfactory outcomes were related to cases with no integration and graft rejection. The least efficiency (from 41,9 to 46,1%) was reported in reconstructive foot surgery. No effect of bone xenografts was observed for replacement of defects in cases of pseudoarthrosis. The most frequent complication was graft material infection. The summarized literature data provided the calculated share of complications following xenograft use of 7,53% (18 out of 239 cases, CI 5-95%, 4,53-11,21). Two areas were identified for improvement of technical and biological properties of bone xenografts: 1. Modification of original xeno-matrix (enhancement of purification technique, alteration of structure of chemical composition of the bone matrix); 2. Augmentation of matrix volume by additional elements (biologically active agents, stem cells). It’s noted that demand for xenografts in traumatology and orthopaedics can increase after refining and expanding the indications for clinical use. Conclusion. Bone xenografts used in the modern trauma surgery and orthopaedics to replace bone defects in revision arthroplasty as well as in certain fracture types. Such material is relatively safe and its ability to be modified allows to improve its biological properties.