MATERIALS AND METHODS: A melatonin-loaded alginate-chitosan/beta-tricalcium phosphate composite hydrogel was successfully prepared and characterized. Thirty-six critical-sized bilateral class II furcation defects were created in six Mongrel dogs, and were randomly divided and allocated to three cohorts; sham, unloaded composite, and melatonin-loaded. Periodontal regenerative capacity was evaluated via histologic and histomorphometric analysis.

RESULTS: Melatonin-treated group showed accelerated bone formation and advanced maturity, with a significant twofold increase in newly formed inter-radicular bone compared with the unloaded composite. The short-term regenerative efficacy was evident 4 weeks postoperatively as a significant increase in cementum length concurrent with reduction of entrapped epithelium. After 8 weeks, the scaffold produced a quality of newly synthesized bone similar to normal compact bone, with potent periodontal ligament attachment.

METHOD: In vitro cell viability, morphology, and alkaline phosphatase (ALP) activity of MC3T3-E1 cells on HA and PCL scaffolds were determined in comparison to the accepted model outlined for two-dimensional systems. An in vivo study involving the transplantation of MC3T3-E1 cells with scaffolds into an artificial bone defect of 4 mm length and 1.5 mm depth in the rat's left maxilla was conducted. Three-dimensional analysis using micro-computed tomography (micro-CT), hematoxylin and eosin (H&E), and immunohistochemistry analyses evaluation were performed after six weeks of transplantation.

MATERIAL AND METHODS: A lyophilisation method was applied, and the outcome was evaluated and compared with traditionally prepared PRF. We investigated how lyophilisation affected PRF's physical characteristics and biological properties by determining: (1) the physical and morphological architecture of Ly-PRF using SEM, and (2) the kinetic release of PDGF-AB using ELISA.

RESULTS: Ly-PRF exhibited a dense and homogeneous interconnected 3D fibrin network. Moreover, clusters of morphologically consistent cells of platelets and leukocytes were apparent within Ly-PRF, along with evidence of PDGF-AB release in accordance with previously reports.

METHODS: This animal protocol has been approved by Universiti Kebangsaan Malaysia Animal Ethical Committee. The TEHB scaffold prepared from hydroxyapatite using gel casting method. A total of six adolescent female sheep were chosen for this study. Later, all the sheep were euthanized in a proper manner and the bone harvested for biomechanical study. Bone marrow was collected from iliac crest of the sheep and bone marrow stem cells (BMSCs) isolated and cultured. BMSCs then cultured in osteogenic medium for osteoprogenitor cells development and the plasma collected was seeded with osteoprogenitor cells mixed with calcium chloride. Bone defect of 3 cm length of tibia bone created from each sheep leg and implanted with autologous and TEHB scaffold in 2 different groups of sheep. Wound site was monitored weekly until the wound completely healed and conventional X-ray performed at week 1 and 24. Shear test was conducted to determine the shear force on the autologous bone and TEHB scaffold after implantation for 24 weeks.

RESULTS: All of the sheep survived without any complications during the study period and radiograph showed new bone formation. Later, the bone harvested was for biomechanical study. The highest shear force for the autologous group was 13 MPa and the lowest was 5 MPa while for the scaffold group, the highest was 10 MPa and the lowest was 3 MPa. Although, proximal and distal interface of autologous bone graft shows higher shear strength compared to the TEHB scaffold but there is no significant difference in both groups, p value > 0.05. Histologically in both proximal and distal interface in both arms shows bone healing and woven bone formation.

MATERIALS AND METHODS: A comprehensive search of five electronic databases, including Medline, PubMed, EMBASE, Web of Science, and Scopus, was conducted from 1946 until 2019 using a combination of search terms relating to this topic.

RESULTS: Ten manuscripts were identified as being relevant. The use of LPCs was mostly studied in in vitro and in vivo craniofacial bone regeneration models. Notably, one clinical study reported the utility of LPCs for guided bone regeneration prior to dental implant placement.

Materials and Methods: Cell viability and cytotoxicity of gelatin (Gel; 50 µg/µl), chitosan (Chi; 20 µg/µl), hydroxyapatite (HA; 50 µg/µl), nanohydroxyapatite (nHA; 10 µg/µl), three-calcium phosphate (TCP; 50 µg/µl) and strontium carbonate (Sr; 10 µg/µl) were evaluated on hADSCs via MTT assay. In vivo femoral drill-bone hole model was produced in rats that were either left untreated or treated with autograft, Gel, Chi, HA, nHA, TCP and Sr, respectively. The animals were euthanized after 30 days. Their bone holes were evaluated by gross-pathology, histopathology, SEM and radiography. Also, their dry matter, bone ash and mineral density were measured.

Results: Both the Gel and Chi showed cytotoxicity, while nHA had no role on cytotoxicity and cell-viability. All the HA, TCP and Sr significantly improved cell viability when compared to controls (P<0.05). Both the Gel and Chi had no role on osteoconduction and osteoinduction. Compared to HA, nHA showed superior role in increasing new bone formation, mineral density and ash (P<0.05). In contrast to HA and nHA, both the TCP and Sr showed superior morphological, radiographical and biochemical properties on bone healing (P<0.05). TCP and Sr showed the most effective osteoconduction and osteoinduction, respectively. In the Sr group, the most mature type of osteons formed.