• International Journal of Oral Biology
• /
• v.44 no.2
• /
• pp.55-61
• /
• 2019

The purpose of this study was to evaluate the effect of mangosteen extract complex (MEC; Garcinia mangostana L. and propolis extracts) on the inhibition of inflammation and prevention of alveolar bone loss using a ligature-induced periodontitis model. Rat molars were ligatured with silk, and $1{\mu}g/mL$ of lipopolysaccharide of Porphyromonas gingivalis was injected into the buccal and palatal gingivae of the teeth with or without treatment with the MEC. Changes in the expression levels of prostaglandin $E_2$ ($PGE_2$), interleukin-8 (IL-8), inducible nitric oxide synthase (iNOS), matrix metalloproteinase-8 (MMP-8), cyclooxygenase (COX)-1, and COX-2 in gingival tissues were evaluated using enzyme-linked immunosorbent assays. Alveolar bone loss around the ligated molars was examined using micro-computed tomography. The expression levels of $PGE_2$, IL-8, iNOS, MMP-8, COX-1, and COX-2 in gingival tissues were significantly reduced in the group treated with a mixture of $16{\mu}g$ of mangosteen extract powder and $544{\mu}g$ of propolis extract powder (ligation [Lig] + lipopolysaccharide extracted from P. gingivalis KCOM 2804 [L] + MEC 1:34). Additionally, alveolar bone loss was significantly reduced in the Lig + L + MEC 1:34 group compared with that in other groups. These results indicate that the MEC could be useful in preventing and treating periodontitis.

• Journal of Korean Dental Science
• /
• v.14 no.1
• /
• pp.12-25
• /
• 2021

Purpose: (i) To evaluate the biologic properties of a bi-layered 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride-cross-linked collagen membrane (CCM) in vitro. (ii) To assess the efficacy of CCM for localized bone regeneration in vivo. Materials and Methods: Biodegradation of CCM compared to a native collagen membrane (NCM) was assessed in vitro. In vivo, twelve male New Zealand White rabbits were used. Four calvarial, circular defects (diameter 8 mm) were created in each animal. The sites were randomly allocated to i) CCM+biphasic calcium phosphate (BCP) (CCM-BCP group), ii) CCM alone (CCM), iii) BCP alone (BCP) and, iv) negative control (control). Animals were sacrificed at 2 (n=6) and 8 weeks (n=6). Outcome measures included: micro-computed tomography (μCT) analysis (total augmented volume [TAV], new bone volume) and histomorphometry (total augmented area [TAA], newly formed bone, remaining membrane thickness [RMT]). Result: CCM was more resistant to degradation than NCM. μCT analysis showed CCM-BCP (196.43±25.30 mm³) and BCP (206.23±39.13 mm³) groups had significantly (P<0.01) larger TAV than the control (149.72±12.28 mm³) after 8 weeks. Histomorphometrically, CCM-BCP group (17.75±5.97 mm²) had significantly (P<0.01) greater TAA compared to the CCM group (7.74±2.25 mm²) and the control (8.13±1.81 mm²) after 8 weeks. After 8 weeks, RMT was reduced by 67%. Conclusion: CCM can be a favorable choice of barrier membrane when performing guided bone regeneration (GBR) in localized bone defects. CCM has better resistance to degradation than the natural collagen membrane, in vitro. In vivo, CCM provides an advantageous integration of prolonged barrier function and biocompatibility for GBR.

• Journal of Periodontal and Implant Science
• /
• v.52 no.5
• /
• pp.370-382
• /
• 2022

Purpose: The aim of this study was to evaluate the preclinical results of 2 types of commercially available deproteinized bovine bone mineral (DBBM) when applied to alveolar bone defects in dogs. Methods: This study was conducted using 6 beagles. Alveolar defects in the mandible were formed and filled with 2 DBBMs produced by a similar procedure. Defects were randomly assigned to be filled using DBBM 1 or 2. All defects were covered with a collagen membrane and had a healing period of 12 weeks. After the dogs were sacrificed, histological, histomorphometric, and linear/volumetric analyses were performed. Results: Both DBBM groups showed similar histological findings, demonstrating that bone remodeling had occurred and new bone had formed. The residual bone particles were surrounded by newly formed vital bone. In the histomorphometric analysis, the ratio of the area of vital bone and residual bone substitute in DBBM 2 (38.18% and 3.47%, respectively) was higher than that of DBBM 1 (33.74% and 3.41%, respectively), although the difference was not statistically significant. There were also no statistically significant differences between both groups in linear and volumetric analyses using micro-computed tomography scans and digitized images of dental casts. Conclusions: In the present study, DBBM 1and 2, which were produced by similar processes, showed similar results in histological, histomorphometric, and volumetric analyses. Further studies are needed to identify more specific differences between the 2 DBBMs.

• Nutrition Research and Practice
• /
• v.15 no.3
• /
• pp.279-293
• /
• 2021

BACKGROUND/OBJECTIVES: The steamed ginger has been shown to have antioxidative effects and a protective effect against obesity. In the present study, we investigated the effects of ethanolic extract of steamed ginger (SGE) on adipogenesis in 3T3-L1 preadipocytes and diet-induced obesity (DIO) mouse model. MATERIALS/METHODS: The protective effects of SGE on adipogenesis were examined in 3T3-L1 adipocytes by measuring lipid accumulations and genes involved in adipogenesis. Male C57BL/6J mice were fed a normal diet (ND, 10% fat w/w), a high-fat diet (HFD, 60% fat w/w), and HFD supplemented with either 40 mg/kg or 80 mg/kg of SGE for 12 weeks. Serum chemistry was measured, and the expression of genes involved in lipid metabolism was determined in the adipose tissue. Histological analysis and micro-computed tomography were performed to identify lipid accumulations in epididymal fat pads. RESULTS: In 3T3-L1 cells, SGE significantly decreased lipid accumulation, with concomitant decreases in the expression of adipogenesis-related genes. SGE significantly attenuated the increase in body, liver, and epididymal adipose tissue weights by HFD. Serum total cholesterol and triglyceride levels were significantly lower in SGE fed groups compared to HFD. In adipose tissue, SGE significantly decreased adipocyte size than that of HFD and altered adipogenesis-related genes. CONCLUSIONS: In conclusion, steamed ginger exerted anti-obesity effects by regulating genes involved in adipogenesis and lipogenesis in 3T3-L1 cell and epididymal adipose tissue of DIO mice.

• Journal of Periodontal and Implant Science
• /
• v.52 no.4
• /
• pp.312-324
• /
• 2022

Purpose: The role of hard-type crosslinked hyaluronic acid (HA) with particulate bone substitutes in bone regeneration for combined inlay-onlay grafts has not been fully investigated. We aimed to evaluate the effect of hard-type crosslinked HA used with bone substitute in terms of new bone formation and space maintenance. Methods: A 15-mm-diameter round defect was formed in the calvaria of 30 New Zealand White rabbits. All animals were randomly assigned to 1 of 3 groups: the control group (spontaneous healing without material, n=10), the biphasic calcium phosphate (BCP) graft group (BCP, n=10), and the BCP graft with HA group (BCP/HA, n=10). The animals were evaluated 4 and 12 weeks after surgery. Half of the animals from each group were sacrificed at 4 and 12 weeks after surgery. Samples were evaluated using micro-computed tomography, histology, and histomorphometry. Results: The BCP group showed higher bone volume/tissue volume (BV/TV) values than the control and BCP/HA groups at both 4 and 12 weeks. The BCP and BCP/HA groups showed higher bone surface/tissue volume (BS/TV) values than the control group at both 4 and 12 weeks. The BCP group showed higher BS/TV values than the control and BCP/HA groups at both 4 and 12 weeks. No statistically significant difference in newly formed bone was found among the 3 groups at 4 weeks. The BCP group showed significantly higher new bone formation than the BCP/HA group at 12 weeks. Conclusions: Hard-type crosslinked HA did not show a positive effect on new bone formation and space maintenance. The negative effect of hard-type crosslinked HA may be due to the physical properties of HA that impede osteogenic potential.

• Journal of Periodontal and Implant Science
• /
• v.53 no.4
• /
• pp.259-268
• /
• 2023

Purpose: Hyaluronic acid (HA) affects angiogenesis and promotes the migration and differentiation of mesenchymal cells, thereby activating the osteogenic ability of osteoblasts. Although studies on the action of HA during bone regeneration are being actively conducted, the optimal dose of HA required for bone regeneration remains unclear. Therefore, the purpose of this study was to elucidate the most effective HA dose for bone formation using a rat critical-size defect model. Methods: Thirty rats were randomly divided into 5 groups, with 6 rats in each group. An absorbable collagen sponge soaked with HA or saline was used to fill an 8-mm defect, which was then covered with a collagen membrane. Different treatments were performed for each group as follows: (1) saline control, (2) 1 mg/mL HA, (3) 25 mg/mL HA, (4) 50 mg/mL HA, or (5) 75 mg/mL HA. After a healing period of 4 weeks, micro-computed tomography and histological analysis were performed. The obtained values were analyzed using analysis of variance and the Tukey test (P<0.05). Results: At week 4, the 75 mg/mL HA group had the highest bone volume/total volume ratio, new bone, and bone fill among the 5 groups, and these values were significantly different from those observed in the control group (P<0.01) and 1 mg/mL HA group (P<0.001). More active bone formation was observed in the higher-dose HA groups (25 mg/mL, 50 mg/mL, and 75 mg/mL HA), which included a large amount of woven bone. Conclusions: The 75 mg/mL HA group showed better bone formation than the other groups (1, 25, and 50 mg/mL HA and control).

• Journal of Periodontal and Implant Science
• /
• v.52 no.6
• /
• pp.479-495
• /
• 2022

Purpose: Rodent models have emerged as an alternative to established larger animal models for peri-implantitis research. However, the construct validity of rodent models is controversial due to a lack of consensus regarding their histological, morphological, and biochemical characteristics. This systematic review sought to validate rodent models by characterizing their morphological changes, particularly marginal bone loss (MBL), a hallmark of peri-implantitis. Methods: This review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. A literature search was performed electronically using MEDLINE (PubMed), and Embase, identifying pre-clinical studies reporting MBL after experimental peri-implantitis induction in rodents. Each study's risk of bias was assessed using the Systematic Review Center for Laboratory animal Experimentation (SYRCLE) risk of bias tool. A meta-analysis was performed for the difference in MBL, comparing healthy implants to those with experimental peri-implantitis. Results: Of the 1,014 unique records retrieved, 23 studies that met the eligibility criteria were included. Peri-implantitis was induced using 4 methods: ligatures, lipopolysaccharide, microbial infection, and titanium particles. Studies presented high to unclear risks of bias. During the osseointegration phase, 11.6% and 6.4%-11.3% of implants inserted in mice and rats, respectively, had failed to osseointegrate. Twelve studies were included in the meta-analysis of the linear MBL measured using micro-computed tomography. Following experimental peri-implantitis, the MBL was estimated to be 0.25 mm (95% confidence interval [CI], 0.14-0.36 mm) in mice and 0.26 mm (95% CI, 0.19-0.34 mm) in rats. The resulting peri-implant MBL was circumferential, consisting of supra- and infrabony components. Conclusions: Experimental peri-implantitis in rodent models results in circumferential MBL, with morphology consistent with the clinical presentation of peri-implantitis. While rodent models are promising, there is still a need to further characterize their healing potentials, standardize experiment protocols, and improve the reporting of results and methodology.

• Restorative Dentistry and Endodontics
• /
• v.46 no.4
• /
• pp.56.1-56.11
• /
• 2021

Objectives: This study evaluated 2 nickel-titanium rotary systems and a complementary protocol with an ultrasonic tip and a small-diameter instrument in flattened root canals. Materials and Methods: Thirty-two human maxillary second premolars with flattened canals (buccolingual diameter ≥4 times larger than the mesiodistal diameter) at 9 mm from the radiographic apex were selected. The root canals were prepared by ProDesign Logic (PDL) 30/0.01 and 30/0.05 or Hyflex EDM (HEDM) 10/0.05 and 25/0.08 (n = 16), followed by application of the Flatsonic ultrasonic tip in the cervical and middle thirds and a PDL 25/0.03 file in the apical third (FPDL). The teeth were scanned using micro-computed tomography before and after the procedures. The percentage of volume increase, debris, and uninstrumented surface area were analyzed using the Kruskal-Wallis, Dunn, Wilcoxon, analysis of variance/Tukey, and paired and unpaired t-tests (α = 0.05). Results: No significant difference was found in the volume increase and uninstrumented surface area between PDL and HEDM (p > 0.05). PDL had a higher percentage of debris than HEDM in the middle and apical thirds (p < 0.05). The FPDL protocol resulted in less debris and uninstrumented surface area for PDL and HEDM (p < 0.05). This protocol, with HEDM, reduced debris in the middle and apical thirds and uninstrumented surface area in the apical third (p < 0.05). Conclusions: High percentages of debris and uninstrumented surface area were observed after preparation of flattened root canals. The HEDM, Flatsonic tip, and 25/0.03 instrument protocol enhanced cleaning in flattened root canals.

• Journal of Periodontal and Implant Science
• /
• v.53 no.3
• /
• pp.218-232
• /
• 2023

Purpose: This study evaluated the efficacy of a tube-shaped poly(ε) caprolactone - β tricalcium phosphate (PCL-TCP) scaffold with the incorporation of human umbilical cord-derived mesenchymal stem cells (hUCMSCs) and platelet-rich plasma (PRP) for bone regeneration in the procedure of single-stage sinus augmentation and dental implantation in minipigs. Methods: Implants were placed in the bilateral sides of the maxillary sinuses of 5 minipigs and allocated to a PCL-TCP+hUCMSCs+PRP group (n=5), a PCL-TCP+PRP group (n=5), and a PCL-TCP-only group (n=6). After 12 weeks, bone regeneration was evaluated with soft X-rays, micro-computed tomography, fluorescence microscopy, and histomorphometric analysis. Results: Four implants failed (2 each in the PCL-TCP+hUCMSCs+PRP and PCLTCP+hUCMSC groups). An analysis of the grayscale levels and bone-implant contact ratio showed significantly higher mean values in the PCL-TCP+hUCMSCs+PRP than in the PCL-TCP group (P=0.045 and P=0.016, respectively). In fluoromicroscopic images, new bone formation around the outer surfaces of the scaffolds was observed in the PCLTCP+hUCMSCs+PRP group, suggesting a tenting effect of the specially designed scaffolds. Bone regeneration at the scaffold-implant interfaces was observed in all 3 groups. Conclusions: Using a tube-shaped, honeycombed PCL-TCP scaffold with hUCMSCs and PRP may serve to enhance bone formation and dental implants' osseointegration in the procedure of simultaneous sinus lifting and dental implantation.

• Anatomy and Cell Biology
• /
• v.56 no.3
• /
• pp.334-341
• /
• 2023

Anterior talofibular ligament (ATFL) injuries are the most common cause of ankle sprains. To ensure anatomically accurate surgery and ultrasound imaging of the ATFL, anatomical knowledge of the bony landmarks around the ATFL attachment to the distal fibula is required. The purpose of the present study was to anatomically investigate the ATFL attachment to the fibula with respect to bone morphology and attachment structures. First, we analyzed 36 feet using micro-computed tomography. After excluding 9 feet for deformities, the remaining 27 feet were used for chemically debrided bone analysis and macroscopic and histological observations. Ten feet of living specimens were observed using ultrasonography. We found that a bony ridge was present at the boundary between the attachments of the ATFL and calcaneofibular ligament (CFL) to the fibula. These two attachments could be distinguished based on a difference in fiber orientation. Histologically, the ATFL was attached to the anterodistal part of the fibula via fibrocartilage anterior to the bony ridge indicating the border with the CFL attachment. Using ultrasonography in living specimens, the bony ridge and hyperechoic fibrillar pattern of the ATFL could be visualized. We established that the bony ridge corresponded to the posterior margin of the ATFL attachment itself. The ridge was obvious, and the superior fibers of the ATFL have directly attached anteriorly to it. This bony ridge could become a valuable and easy-to-use landmark for ultrasound imaging of the ATFL attachment if combined with the identification of the fibrillar pattern of the ATFL.