The effect of autogenous tooth bone graft material without organic matter and type I collagen treatment on bone regeneration / 대한악안면성형재건외과학회지

Objectives@#The aim of this study is to examine the effect of particulate autogenous tooth graft removed with organic matter and type I collagen addition on bone regeneration and to validate the possibility of useful allograft material for jaw defects.Material and methods: Autogenous tooth bone maker (Korean Dental Solution® KOREA) made particulate autogenous tooth not including organic matter. We used to the developed tooth grafts for experiment. Cell adhesion test with hemacytometer and energy dispersive X-ray spectroscopy (Supra40 VP®, Carl Zeiss, Germany) analysis about the particulate autogenous tooth and type I collagen were performed. Rabbits were divided into three groups: bone graft with organic matter (OM) removing particulate autogenous tooth group, bone graft with OM removing particulate autogenous tooth and type I collagen group, and a control group. Bone grafting was performed in rabbit’s calvaria. The rabbits were sacrificed at different interval at 1, 2, 4, and 6 weeks after bone grafting for the histopathologic observation and observed the effect of bone regeneration by SEM, H-E & Masson stains, osteocalcin IHC staining.Result: In vitro cytopathological study showed affinity for cells, cell attachment pattern, and cell proliferation in the order of control group, OM-removed and collagen-treated group, OM-removed particulate autogenous tooth group. The results of the degree of mineralization were opposite to those of the previous cell experimental results, and the OM-removed group, OM-removed group and collagen-treated group were relatively higher than the control group. Histopathologic analysis showed that vascularization and neonatal bone formation were higher in particulate autogenous tooth group with removing OM and with addition of collagen than control group and group of OM removed only. Immunohistochemical analysis showed that osteocalcin (OSC) expression was not observed in the control group, but at 4 weeks groups, OSC expression was observed the OM removed and OMremoved-collagen-treated particulate autogenous tooth, and the degree of expression was somewhat stronger in group of the OM removed and collagen additionally treated particulate autogenous tooth. @*Conclusion@#Particles that do not contain organic matter, the saint tooth, was responsible for sufficient bone graft material through the role of space maintenance and bone conduction, and further improved bone formation ability through additional collagen treatment. Therefore, research on various extracellular substrates and autologous bone grafting materials is necessary, and through this, it is possible to lay the foundation for a new type of autologous bone grafting material with excellent academic and technical utility.

Effectiveness of mentha extracts against oral microorganisms: an in vitro study / 대한구강보건학회지

Objectives@#Dental caries and periodontal disease are infectious and chronic diseases. The aim of the study was to investigate the antimicrobial effect of mentha extracts against Streptococcus mutans (S. mutans ) and Porphyromonas gingivalis (P. gingivalis ). @*Methods@#This activity of mentha extracts were confirmed by the disk diffusion test and minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and colony forming unit (CFU) assays. @*Results@#S. mutans and P. gingivalis showed the highest antimicrobial activity within the inhibition zones. The antimicrobial activity was interrupted as the MIC and MBC of the herbal extracts against the two bacteria were 1 mg/ml and 10 mg/ml, respectively. The antimicrobial effect was determined by the CFU assay. @*Conclusions@#Mentha herb extract demonstrated potential antimicrobial activity against S. mutans and P. gingivalis that cause dental caries and periodontal disease.

Effect of apoptosis on G361 cells by Cimicifuga rhizoma extract / 대한구강보건학회지

OBJECTIVES: To investigate whether the cytotoxic effect of Cimicifuga rhizoma extract is associated with cell death in the human keratinocyte (HaCaT) and human melanoma cell lines (G361). METHODS: Apoptosis induced by Cimicifuga rhizoma extract was confirmed by water-soluble tetrazolium salts-1 (WST-1) assay, immunocytochemistry, and western blot. Additionally, the release of cytochrome c and apoptosis-inducing factor (AIF) was visualized by confocal laser scanning microscopy. RESULTS: The results showed that Cimicifuga rhizoma extract significantly reduced the viability of G361 cells with half-maximal inhibitory concentration (IC 50) of 200 µg/ml, and the apoptotic process was found to occur via the activation of caspase-3 and caspase-9 pathways. Besides, the release of cytochrome c and AIF was also detected. CONCLUSIONS: This study suggests that Cimicifuga rhizoma extract causes apoptosis of human melanoma cells through the intrinsic apoptotic pathway.

Induction of Melanoma Cell-Selective Apoptosis Using Anti-HER2 Antibody-Conjugated Gold Nanoparticles

PURPOSE: This study was conducted to verify the induction and mechanism of selective apoptosis in G361 melanoma cells using anti-HER2 antibody-conjugated gold nanoparticles (GNP-HER2). MATERIALS AND METHODS: Following GNP-HER2 treatment of G361 cells, cell cycle arrest and apoptosis were measured by WST-1 assay, Hemacolor staining, Hoechst staining, immunofluorescence staining, fluorescence-activated cell sorting analysis, and Western blotting.

Langerhans cell histiocytosis of the mandible: two case reports and literature review

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by the proliferation of dendritic cells resulting in local or systemic symptoms. The clinical symptoms of patients with Langerhans cell histiocytosis depend on the site and the degree of involvement. This article describes two case histories of unifocal bony Langerhans cell histiocytosis with mandibular involvement and further discusses the appropriate management of such via a review of the literature.

Langerhans cell histiocytosis of the mandible: two case reports and literature review

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by the proliferation of dendritic cells resulting in local or systemic symptoms. The clinical symptoms of patients with Langerhans cell histiocytosis depend on the site and the degree of involvement. This article describes two case histories of unifocal bony Langerhans cell histiocytosis with mandibular involvement and further discusses the appropriate management of such via a review of the literature.

Reconstruction of cheek mucosal defect with a buccal fat pad flap in a squamous cell carcinoma patient: a case report and literature review / 대한악안면성형재건외과학회지

BACKGROUND: Squamous cell carcinoma (SCC) is the most commonly occurring malignant tumor in the oral cavity. In South Korea, it occurs most frequently in the mandible, tongue, maxilla, buccal mucosa, other areas of the oral cavity, and lips. Radial forearm free flap (RFFF) is the most widely used reconstruction method for the buccal mucosal defect. The scar of the forearm donor, however, is highly visible and unsightly, and a secondary surgical site is needed when such technique is applied. For these reasons, buccal fat pad (BFP) flap has been commonly used for closing post-surgical excision sites since the recent decades because of its reliability, ease of harvest, and low complication rate. CASE PRESENTATION: In the case reported herein, BFP flap was used to reconstruct a cheek mucosal defect after excision. The defect was completely covered by the BFP flap, without any complications. CONCLUSION: Discussed herein is the usefulness of BFP flap for the repair of the cheek mucosal defect. Also, further studies are needed to determine the possibility of using BFP flap when the defect is deep, and the maximum volume that can be harvested considering the changes in volume with age.

Retrospective clinical study of multiple keratocystic odontogenic tumors in non-syndromic patients

OBJECTIVES: A keratocystic odontogenic tumor (KOT) is a type of odontogenic tumor that mainly occurs in the posterior mandible. Most KOTs appear as solitary lesions; however, they sometimes occur as multiple cysts. This study analyzed the clinical features of multiple KOTs. MATERIALS AND METHODS: The participants were diagnosed with KOT by biopsy with multiple surgical sites, and were patients at the Pusan National University Hospital and the Pusan National University Dental Hospital from January 1, 2005 to March 31, 2016. Charts, records, images and other findings were reviewed. RESULTS: A total of 31 operations were conducted in 17 patients. The mean patient age was 28.4±20.1 years. Multiple KOTs were found to occur at a young age (P<0.01). The predominant sites were in the posterior mandible (28.6%). Most cases of multiple lesions appeared in both the upper and lower jaw, and 40.3% of lesions were associated with unerupted and impacted teeth. The overall recurrence rate measured by operation site was 10.4% (8/77 sites). No patients were associated with nevoid basal cell carcinoma syndrome. CONCLUSION: The pure recurrence rate was lower than estimated, but there was a higher possibility of secondary lesions regardless of the previous operation site; therefore, long-term follow-up is necessary.

Dentinal Tubules Occluding Effect Using Nonthermal Atmospheric Plasma

Nonthermal atmospheric plasma has been studied for its many biomedical effects, such as tooth bleaching, wound healing, and coagulation. In this study, the effects of dentinal tubules occlusion were investigated using fluoride-carboxymethyl cellulose (F-CMC) gel, nano-sized hydroxyapatite (n-HA), and nonthermal atmospheric plasma. Human dentin specimens were divided to 5 groups (group C, HA, HAF, HAP, and HAFP). Group HA was treated with n-HA, group HAF was treated with n-HA after a F-CMC gel application, group HAP was treated with n-HA after a plasma treatment and group HAFP was treated with n-HA after a plasma and F-CMC gel treatment. The occlusion of dentinal tubules was investigated using scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS), which shows Ca/P ratio. In the EDS results, a higher Ca/P ratio was shown in the groups including n-HA than in the control group. The specimens of group HAP and HAFP had a higher Ca/P ratio in retentivity. In the SEM results, there was not a significant difference in the amount of times applied. Therefore, this study suggests F-CMC gel and n-HA treatment using nonthermal atmospheric plasma will be a new treatment method for decreasing hypersensitivity.

Relationship between disease stage and renal function in bisphosphonate-related osteonecrosis of the jaw

OBJECTIVES: Bisphosphonate is the primary cause of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Bisphosphonates are eliminated from the human body by the kidneys. It is anticipated that bisphosphonate levels in the body will increase if the kidney is in a weak state or if there is systemic disease that affects kidney function. The aim of this study was to analyze the relevance of renal function in the severity of BRONJ. MATERIALS AND METHODS: Ninety-three patients diagnosed with BRONJ in Pusan National University Dental Hospital from January 2012 to December 2014 were included in this study. All patients underwent a clinical exam, radiographs, and serologic lab test, including urine analysis. The patient's medical history was also taken, including the type of bisphosphonate drug, the duration of administration and drug holiday, route of administration, and other systemic diseases. In accordance with the guidelines of the 2009 position paper of American Association of Oral and Maxillofacial Surgeons, the BRONJ stage was divided into 4 groups, from stage 0 to 3, according to the severity of disease. IBM SPSS Statistics version 21.0 (IBM Co., USA) was used to perform regression analysis with a 0.05% significance level. RESULTS: BRONJ stage and renal factor (estimated glomerular filtration rate) showed a moderate statistically significant correlation. In the group with higher BRONJ stage, the creatinine level was higher, but the increase was not statistically significant. Other factors showed no significant correlation with BRONJ stage. There was a high statistically significant correlation between BRONJ stage and ‘responder group’ and ‘non-responder group,’ but there was no significant difference with the ‘worsened group.’ In addition, the age of the patients was a relative factor with BRONJ stage. CONCLUSION: With older age and lower renal function, BRONJ is more severe, and there may be a decrease in patient response to treatment.

The effect of biomechanical stimulation on osteoblast differentiation of human jaw periosteum-derived stem cells / 대한악안면성형재건외과학회지

BACKGROUND: This study was to investigate the effect of biomechanical stimulation on osteoblast differentiation of human periosteal-derived stem cell using the newly developed bioreactor. METHODS: Human periosteal-derived stem cells were harvested from the mandible during the extraction of an impacted third molar. Using the new bioreactor, 4% cyclic equibiaxial tension force (0.5 Hz) was applied for 2 and 8 h on the stem cells and cultured for 3, 7, and 14 days on the osteogenic medium. Biochemical changes of the osteoblasts after the biomechanical stimulation were investigated. No treatment group was referred to as control group. RESULTS: Alkaline phosphatase (ALP) activity and ALP messenger RNA (mRNA) expression level were higher in the strain group than those in the control group. The osteocalcin and osteonectin mRNA expressions were higher in the strain group compared to those in the control group on days 7 and 14. The vascular endothelial growth factor (VEGF) mRNA expression was higher in the strain group in comparison to that in the control group. Concentration of alizarin red S corresponding to calcium content was higher in the strain group than in the control group. CONCLUSIONS: The study suggests that cyclic tension force could influence the osteoblast differentiation of periosteal-derived stem cells under optimal stimulation condition and the force could be applicable for tissue engineering.

Corrigendum: Relationship between disease stage and renal function in bisphosphonate-related osteonecrosis of the jaw

This correction is being published to correct the approval number of the Institutional Review Board in this article.

The Effect of Autogenous Demineralized Dentin Matrix and Interleukin-6 on bone Regeneration

The aim of this study was to evaluate the role of demineralized and particulate autogenous tooth, and interleukin-6 in bone regeneration. A demineralized and particulate autogenous tooth was prepared and human osteoblast-like cells (MG63) and human osteosarcoma cells were inoculated into the culture. The rate of cell adhesion, proliferation and mineralization were examined, and the appearance of cellular attachment was observed. An 8 mm critical size defect was created in the cranium of rabbits. Nine rabbits were divided into three groups including: An experimental group A (3 rabbits), in which a demineralised and particulate autogenous tooth was grafted; an experimental group B (3 rabbits), in which a demineralized, particulate autogenous tooth was grafted in addition to interleukin-6 (20 ng/mL); and a control group. The rabbits were sacrificed at 1, 2, 4 and 6 weeks for histopathological examination with H-E and Masson's Trichrome, and immunohistochemistry with osteocalcin. The cell-based assay showed a higher rate of cell adhesion, mineralization and cellular attachment in the experimental group A compared with the control group. The animal study revealed an increased number of osteoclasts, newly formed and mature bones in the experimental group A compared with the control group. Eventually, a higher number of osteoclasts were observed in the experimental group B. However, the emergence of newly formed and mature bone was lower than in the experimental group A. The current results suggest that treatment with demineralized and particulate autogenous tooth and interleukin-6 is not effective in stimulating bone regeneration during the bone grafting procedure.

An Evaluation of the Repetitive Tooth Bleaching with Nonthermal Atmospheric Pressure Plasma

This study was undertaken to achieve a high bleaching efficacy with plasma, through longer application and reparative bleaching processes, by different shade evaluation methods. Extracted human teeth were divided into 6 groups (n=10). All teeth were treated in pairs. Low concentration of 15% carbamide peroxide (CP) was applied, with and without plasma, for 10, 20, and 30-min tooth bleaching, respectively. The bleaching procedure was repeated once daily for four days. The teeth were maintained in a moist environment provided by artificial saliva. The Vitapan Classical shade guide and Commission Internationale de L'Eclairage (CIELAB) color system were collectively used to measure the bleaching efficacy. Color evaluation was statistically analyzed using Student t-test and one-way analysis of variance (ANOVA) complemented by Tukey's test. Combining the plasma with 15% CP showed significantly greater color changes compared to bleaching without plasma (p<0.05). A high bleaching efficacy with plasma is proportional to the repetitive application and the treatment time. A 30-min application with plasma provided the best bleaching. Repetitive bleaching showed lower probability of color relapse of the bleached tooth. The color change by shade guide correlated with the changes in CIELAB color system. A value of 1 color change units (CCU) conversion factor for overall color change (ΔE) values comparisons was 3.724 values. The two measuring methods provide a more accurate correspondence of color change. The repetitive and longer application for tooth bleaching, combined with plasma, has a strong bleaching effect and produces whiter teeth.

Antimicrobial Effect of Low Temperature Atmospheric Plasma against Oral Pathogens

The purpose of this study was to investigate the antibacterial effect of the low temperature atmospheric plasma device with needle tip designed for easy approach to the oral cavity and root canal against Streptococcus mutans, Enterococcus faecalis and Candida albicans. The antibacterial activities evaluated by measuring clear zone of agar plate smeared with each bacteria after plasma treatment. To quantify antibacterial effects, dilution plate method was used. In addition, scanning electron microscope (SEM) was used for observation of changes in bacterial morphology. As treatment time of plasma increased, the clear zone was enlarged. The death rate was more than 99%. The SEM results showed that the globular shape of bacteria was distorted. These results suggest that needle tip plasma could be an innovative device for prevention of dental caries, and treatment of apical infection and soft tissue diseases.

Evaluation of the safety of non-thermal atmospheric-pressure plasma in hairless mouse tissues / 대한구강보건학회지

OBJECTIVES: The aim of the present study was to evaluate the stability of non-thermal atmospheric-pressure plasma on Candida albicans in hairless mouse-2 (HRM-2) tissues. METHODS: HRM-2 mice were subjected to non-thermal atmospheric-pressure plasma jet treatment using an optical fiber probe and monitored using a thermometer. The skin of HRM-2 mice was treated with plasma jet for 0, 60, 180, and 300 s per day for 5 days. After plasma treatment, morphological changes in Candida albicans on the skin of these mice were examined using a scanning electron microscope. Biopsy of the plasma-treated skin was performed and the tissues were histologically analyzed using hematoxylin and eosin (H&E) and Masson's trichrome stains. RESULTS: The scanning electron microscopic images revealed the morphological changes in the membrane structure of the plasma-treated Candida albicans. Histological analysis showed that non-thermal plasma treatment did not cause epidermal damage or tissue inflammation and did not significantly modify the collagen layers of the mouse skin. CONCLUSIONS: The results of this study suggest that non-thermal atmospheric-pressure plasma might be safe and effective for clinical applications in the field of dentistry.

Apoptotic Effect of Co-treatment with Curcumin and Cisplatin on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line

Curcumin is a widely used flavoring agent in food, and it has been reported to inhibit cell growth, to induce apoptosis, and to have antitumor activity in many cancers. Cisplatin is one of the most potent known anticancer agents and shows significant clinical activity against a variety of solid tumors. This study was undertaken to investigate the synergistic apoptotic effects of co-treatment with curcumin and cisplatin on human tongue SCC25 cells. To investigate whether the co-treatment efficiently reduced the viability of the SCC25 cells compared with the two treatments separately, an MTT assay was conducted. The induction and the augmentation of apoptosis were confirmed by DNA electrophoresis, Hoechst staining, and an analysis of DNA hypoploidy. Western blot, MMP and immunofluorescence tests were also performed to evaluate the expression levels and the translocation of apoptosis-related proteins following the co-treatment. In this study, following the co-treatment with curcumin and cisplatin, the SCC25 cells showed several forms of apoptotic manifestation, such as nuclear condensation, DNA fragmentation, reduction of MMP, increased levels of Bax, decreased levels of Bcl-2, and decreased DNA content. In addition, they showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40 (CAD) to the nuclei, and activation of caspase-7, caspase-3, PARP, and DFF45 (ICAD). In contrast, separate treatments of 5 microM of curcumin or 4 microg/ml of cisplatin, for 24 hours, did not induce apoptosis. Therefore, our data suggest that combination therapy with curcumin and cisplatin could be considered as a novel therapeutic strategy for human oral squamous cell carcinoma.

Erratum: Evaluation of the safety of non-thermal atmospheric-pressure plasma in hairless mouse tissues / 대한구강보건학회지

We correct a typo in the title.

Mechanism Underlying Curcumin-induced Apoptosis and Cell Cycle Arrest on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line

Several studies have shown that curcumin, which is derived from the rhizomes of turmeric, possesses antimicrobial, antioxidant and anti-inflammatory properties. The antitumor properties of curcumin have also now been demonstrated more recently in different cancers. This study was undertaken to investigate the modulation of cell cycle-related proteins and the mechanisms underlying apoptosis induction by curcumin in the SCC25 human tongue squamous cell carcinoma cell line. Curcumin treatment of the SCC25 cells resulted in a time- and dose-dependent reduction in cell viability and cell growth, and onset of apoptotic cell death. The curcumin-treated SCC25 cells showed several types of apoptotic manifestations, such as nuclear condensation, DNA fragmentation, reduced MMP and proteasome activity, and a decreased DNA content. In addition, the treated SCC25 cells showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40/CAD into the nuclei, a significant shift in the Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-7, caspase-6, caspase-3, PARP, lamin A/C, and DFF45/ICAD. Furthermore, curcumin exposure resulted in a downregulation of G1 cell cycle-related proteins and upregulation of p27KIP1. Taken together, our findings demonstrate that curcumin strongly inhibits cell proliferation by modulating the expression of G1 cell cycle-related proteins and inducing apoptosis via proteasomal, mitochondrial, and caspase cascades in SCC25 cells.

Alteration of Hydroxyapatite Surface after Tooth Bleaching with Nonthermal Atmospheric Pressure Plasma

Nonthermal atmospheric pressure plasma has attracted great interest for biomedical applications. The plasma consists of charged particles, radicals, and a strong electric field as the fourth state of matter. This study evaluated the change in the surface roughness after tooth bleaching by plasma in combination with a low concentration (15%) of carbamide peroxide, specifically whether the application of plasma produced detriments, such as demineralization and structural change, with the goal of efficient and safe tooth bleaching. After being combined with plasma and 15% carbamide peroxide, the hydroxyapatite surface was significantly smoother with a low roughness average value. Tooth bleaching with 15% carbamide peroxide alone produced an irregular surface and increased the surface roughness with high roughness average value. Tooth bleaching with plasma resulted in no significant variations in hydroxyapatite in terms of change in surface roughness and surface topography. The application of tooth bleaching with plasma is not deleterious to dental hard tissue, implicating it as a safe tooth bleaching technique.