Journal of Dental Medicine

Statement of Problem: Several methods are used to enhance bone repair and new bone formation, and bone matrix gelatin (BMG) is recently introduced.

Purpose: The purpose of this histologic and histomorphometric study was to assess the osteogenic potential and the quantity of new trabecular bone formation after implantation of OCP and BMG alone and in combination into the cranial defects in rat.

Materials and Methods: In this experimental study, 100 young male Sprague Dawley rats (5-6 weeks age and 120-150gr weight) were divided into four groups randomly. A full thickness standard trephine defect 5mm in diameter was made in the rat’s parietal bone, and 5mg of OCP, BMG alone and in combination were implanted into the defects. No OCP and BMG particles were implanted in control group which was otherwise treated identically. On the 5th, 7th, 14th, 21st and 56th days after implantation, the rats were killed and bone samples collected. After processing the samples by routine histological procedures, 5µm thick sections of bone were cut and stained with Haematoxyline & Eosin (H&E) and Alcian Blue and studied histologically and histomorphometrically using light microscope and eyepiece graticule. The amount of newly formed bone was quantitatively measured by the use of histomorphometric methods. Data were analyzed with SAS statistical package using ANOVA and Duncan tests.

Results: In the experimental groups, the new bone formation was initiated from the margin of defects during 5-14 days after implantation. During 14-21 days after implantation, bone marrow cavities and bone marrow tissues in newly formed bone were seen. By the end of the study, the newly formed bone increased and was relatively matured and almost all of the implanted materials were absorbed. In control group, at the end of the study, a few clusters of new bone were seen near to the defect margins and host bone. The histomorphometric analysis indicated statistical significant differences in the amount of newly formed bone between the experimental and control groups (P<0.05).

Conclusion: Implants of OCP/BMG appear to stimulate bone induction and new bone growth in bone defects greater than the other groups and these biomaterials could be used in the repair of cranial bone defects in clinical situations.

  Background and Aims: Until now, different types of scaffolds are presented for hard tissue engineering and the research continues to find the best scaffold. The aim of this study was to prepare scaffolds using two types of composite materials, ChitosanTriCalcium Phosphate (C/TCP) and ChitosanTriCalcium Phosphate/ Hydroxy apatite (C/TCP/ HA) and to add either 10% or 20% gelatin to compare their influence on swelling ratio of the scaffolds and on their affinities towards Dental Pulp Stem Cells (DPSCs).

  Materials and Methods: Composite scaffolds containing 10 or 20 percent of gelatin were prepared by freeze drying method. To determine the percentage of water absorption, swelling ratio studies were performed. Cell attachment and cell viability of the composite scaffolds were studied using Scanning Electron Microscopy (SEM) and MTT ( dimethyl-thiazol-diphenyltetrazolium bromide ) assay. Data were analyzed using ANOVA and Turkey’s post hoc test. A P-value of <0.05 was considered to be statistically significant.

  Results: The C/TCP scaffold and scaffolds containing 20% gelatin showed good swelling character. The macroporous composite scaffolds exhibited different pore structures. The biological response of DPS cells on C/TCP scaffold, C/TCP scaffold containing 20% gelatin, and C/TCP/HA scaffold was superior in terms of cell attachment, proliferation, and spreading compared to the other scaffolds (P<0.05).

  Conclusion: Considering the limitations of this in vitro studies, the results demonstrated that enhanced gelatin content in the C/TCP scaffolds do not improve initial cell adhesion and proliferation of the DPSCs on these scaffolds.