The aim of this study was to isolate stem cells from dental pulp of primary molars and incisors to be used as possible source for tissue engineering. Human primary molars and incisors were collected from subjects aged 4-7 year-old under standardized procedures. Within 24 hours, the tooth was cut at the cemento-enamel junction using hard tissue material cutter. The dental pulp tissue was extracted, digested and then cultured in Alpha Modified Eagles's Medium (α-MEM) supplemented with 20% FCS, 100 mM L-ascorbic acid 2-phosphate, 200 mM L-glutamine and 5000 units/ml Penicillin/Streptomycin. The cells were observed daily under the microscope until confluence. Children's tooth pulp- derived progenitor cells were found positive for stem cell markers CD105 and CD166, which are consistent with the finding for mesenchymal stem cells (MSCs) from bone marrow.
The study was carried out to evaluate macroscopically the ability of coral to repair a large size bone defect. A total 12 adult, male sheep were used in the study. The large bone defect (2.5cm x 0.5cm x 0.5cm) was created surgically on the left proximal femur and replaced by a block of coral (Porites sp.). Radiographs were obtained immediately after surgery and at 2, 4, 8 and 12 weeks post-implantation. Ultrasonographic examinations were carried out every 2 weeks after implantation up to 12 weeks using ultrasound machine (TOSHIBA Capasee II) connected with 7MHz frequency transducer. The sheep were euthanased at 2, 4, 8, and 12 weeks post-implantation and the bone examined grossly. Both ultrasonographs and radiographs taken at 8 and 12 weeks showed that the implants had been resorbed and left the space that much reduced in size. There was no sign of implant rejection observed in all animals. The results showed that processed coral has potential to become bone substitute for reconstructive bone surgery.
The aim of this study was to evaluate the in vitro cytotoxicity of biomaterials; Hydroxyapatite (HA), Natural coral (NC) and Polyhydroxybutarate (PHB). Three different materials used in this study; HA (Ca10(PO4)6(OH)2), NC (CaCO3) and PHB (Polymer) were locally produced by the groups of researcher from Universiti Sains Malaysia. The materials were separately extracted in the complete culture medium (100mg/ml) for 72h and introduced to the osteoblast cells CRL-1543. The viability of osteoblast CRL-1543 cultivated with these extraction materials after 72h incubation period was compared to negative control with neutral red assay by using spectrophotometer at 540nm. The results showed the non-cytotoxicity of the materials. After 72h of incubation period, HA showed 123% viable cells, NC was 99.43% and PHB was 176.75%. In this study, cytotoxicity test dealt mainly with the substances that leached out from the biomaterial. The results obtained showed that the materials were not toxic and also promoted cells growth in the sense of biofunctionality.
The study was carried out with the aim to evaluate natural coral (Porites spp.) implanted in sheep femur microscopically. Twelve adult, male sheep were used in this study. The defect area was implanted with coral and monitored for up to 12 weeks. The sheep were euthanased at 2,4,8, and 12 weeks post-implantation. Microscopically, natural coral implanted into bone tissue have shown gradual resorption and progressively replaced by new bone. At 12 weeks post-implantation, the implanted site was almost completely surrounded by mature bone. The results showed that natural coral was found to be a biodegradable and osteo-conductive biomaterial, which acted as a scaffold for a direct osteoblastic apposition.