Search Results (5)

Background/Objectives: Achieving a sufficient volume of augmented bone, particularly for vertical bone regeneration, remains challenging. This study investigated the use of basic fibroblast growth factor 2 (FGF-2) to promote bone augmentation beyond the skeletal envelope in the rat calvarium. Methods: Seven rats were included in the study, with bilateral experimental sites in the calvarium. Two plastic caps were placed in the calvarium, containing either 0.3% FGF-2 with an atelocollagen sponge or an atelocollagen sponge alone as a control. Bone augmentation within the plastic caps was evaluated using micro-computed tomography (micro-CT) scans and histological sections. Micro-CT measurements, including bone volume measurements, were obtained at 1 week to 12 weeks after surgery. At 12 weeks, the area and height of the newly formed bone were evaluated using histological sections. Results: Starting at 8 weeks after surgery, the volume of the newly formed bone in the 0.3% FGF-2 group was significantly greater than that in the control group. At 12 weeks, histomorphometric analyses revealed that the area and height of the newly augmented bone were 35.6% and 41.9%, respectively, in the FGF-2 group, compared with 9.1% and 13.4%, respectively, in the control group. Conclusions: The inclusion of 0.3% FGF-2 in atelocollagen sponge enhanced vertical bone augmentation beyond the skeletal envelope in the rat calvarium. These findings have potential applications for improving bone regeneration outcomes in dental implant procedures. Full article

This in vivo study reports the influence of minocycline-HCl administration on extra-skeletal bone generation in a Guided Bone Augmentation model, utilizing titanium caps placed on the intact as well as perforated calvaria of rats. The test group was administered 0.5 mg/mL minocycline-HCl with the drinking water, and the amount of bone tissue in the caps was quantified at three time points (4, 8 and 16 weeks). A continuously increased tissue fill was observed in all groups over time. The administration of minocycline-HCl as well as perforation of the calvaria increased this effect, especially with regard to mineralization. The strongest tissue augmentation, with 1.8 times that of the untreated control group, and, at the same time, the most mineralized tissue (2.3× over untreated control), was produced in the combination of both treatments, indicating that systemic administration of minocycline-HCl has an accelerating and enhancing effect on vertical bone augmentation. Full article

This paper aims to evaluate the healing capacity of bony lesions around biofilm-infected and non-infected gutta-percha (GP) points. Bony defects were created in the calvaria of 28 Wistar rats. The rats were divided into three groups: Group 1—Implantation of infected GP particles in the bony defect; Group 2—Positive control implantation of non-infected GP particles in the bony defect; and Group 3—Negative control, in which no GP particles were implanted. The biofilm consisted of three strains of bacteria: Enterococcus faecalis, Streptococcus sanguis, and Porphyromonas gingivalis. The animals were sacrificed 60 days postoperation, and histological assessments were performed. In Group 1, the biofilm-infected group, we observed a mild foreign body reaction with a few inflammatory cells adjacent to the capsule and a newly woven bone matrix surrounded by osteoblasts and mature bone. In Group 2, the non-infected GP particles group, minimal inflammatory cell reactions were observed in the adjacent tissue, and a newly woven bone matrix was surrounded by osteoblasts. This study shows that bone healing is possible around both sterile and infected GP points. This contradicts the claim that some root canal treatments fail because of non-microbial factors, including extruded root canal filling materials, which may cause foreign body reactions. The healing observed suggests that overextension should not be considered an indication for endodontic surgery. Full article

The aim of this study was to evaluate the bone regeneration effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) on a subperiosteal bone graft in a rat model. A subperiosteal space was made on the rat calvarium, and anorganic bovine bone (ABB), ABB/low bone morphogenetic protein (BMP) (5 µg), and ABB/high BMP (50 µg) were grafted as subperiosteal bone grafts. The new bone formation parameters of bone volume (BV), bone mineral density (BMD), trabecular thickness (TbTh), and trabecular spacing (TbSp) were evaluated by microcomputed tomography (µ-CT), and a histomorphometric analysis was performed to evaluate the new bone formation area. The expression of osteogenic markers, such as bone sialoprotein (BSP) and osteocalcin, were evaluated by immunohistochemistry (IHC). The ABB/high BMP group showed significantly higher BV than the ABB/low BMP (p = 0.004) and control groups (p = 0.000) and higher TbTh than the control group (p = 0.000). The ABB/low BMP group showed significantly higher BV, BMD, and TbTh than the control group (p = 0.002, 0.042, and 0.000, respectively). The histomorphometry showed significantly higher bone formation in the ABB/low and high BMP groups than in the control group (p = 0.000). IHC showed a high expression of BSP and osteocalcin in the ABB/low and high BMP groups. Subperiosteal bone grafts with ABB and rhBMP-2 have not been studied. In our study, we confirmed that rhBMP-2 contributes to new bone formation in a subperiosteal bone graft with ABB. Full article

A major drawback of nanocomposite scaffolds in bone tissue engineering is dimensional shrinkage after the fabrication process. Shrinkage yields gaps between the scaffold and host bone in the defect site and eventually causes failure in osteointegration by micromovement. The present study was conducted using titanium (Ti) mesh and Gelfoam^® to prevent radial and axial micromovement, respectively. A critical-sized defect (CSD) was created in the center of the calvarium of Sprague Dawley rats to implant porous polydopamine-laced hydroxyapatite collagen calcium silicate (HCCS-PDA), a novel nanocomposite scaffold. Gelfoam^® was applied around the edge of the defect, and then the HCCS-PDA scaffold was inserted in the defect area. Ti mesh was placed between the periosteum and skin right, above the inserted scaffold site. There were two test groups, with a fixture (Gelfoam^® and Ti mesh) and without a fixture, each group contained five animals. The rats were sacrificed after three months post-operation. The explanted calvaria underwent micro-CT scanning and a push-out test to quantify osteointegration and mechanical strength between the scaffold and host bone. Histological analysis of undecalcified bone was performed by grinding resin infiltrated calvaria blocks to prepare 10 μm slices. Osteointegration was higher in the group with fixation than without fixation. Movement of the HCCS-PDA scaffold in the gap resulted in diminished osteointegration. With fixation, the movement was inhibited and osteointegration became prominent. Here we present a successful method of preventing axial and radial movement of scaffolds using Gelfoam^® and Ti mesh. Applying this fixture, we expect that an HCCS-PDA scaffold can repair CSD more effectively. Full article