Adjunctive recombinant human parathyroid hormone agents for the treatment of medication-related osteonecrosis of the jaw: a report of three cases

Teriparatide has been effective in treating people diagnosed with medication-related osteonecrosis of the jaw (MRONJ). However, its efficacy is not well established to be accepted as a standard of care. The objective of this paper was to investigate the efficacy of recombinant human parathyroid hormone for the treatment of MRONJ. We report three cases of MRONJ patients with osteoporosis as the primary disease who were treated with a teriparatide agent along with other adjunctive measures. Each patient was administered a teriparatide injection subcutaneously for 16 weeks, 36 weeks, or 60 weeks. Surgical intervention including partial resection, sequestrectomy, decortication, and saucerization took place during the teriparatide administration. Complete lesion resolution was identified clinically and radiographically in all three patients. In patients diagnosed with MRONJ, teriparatide therapy is an efficacious and safe therapeutic option to improve healing of bone lesions. These findings demonstrate that teriparatide in combination with another therapy, especially bone morphogenetic protein, platelet-rich fibrin, or antibiotic therapy, can be an effective protocol for MRONJ.

Interpositional bone graft with cortical and cancellous calvarial bone for addressing the bone gap after reduction malarplasty: a case report

Asians typically exhibit prominent zygomas; therefore, several attempts have been made to reduce these structures to achieve a softer appearance. The intraoral approach is preferred because of its shorter surgical duration and lower invasiveness; however, it is associated with serious complications, such as nonunion. In revisional surgery, the intraoral approach poses limitations in accessing the upper part of the zygoma and the lateral orbital rim area due to its restricted operative field. Therefore, we developed an intraoral interpositional bone graft technique that enabled almost complete reconstruction. A 40-year-old woman presented with persistent depression in the left infraorbital and cheek regions after two revision operations after reduction malarplasty. Based on computed tomography (CT) scan findings, reconstruction using bone grafts was planned. Calvarial bone was harvested and divided into cortical and cancellous parts. The cortical bone was sculpted into an L-shape and inserted into the gap between the maxilla and the lower zygoma body. The hard-to-reach lateral orbital rim area was filled with cancellous bone without fixation. Follow-up CT scans showed that the cortical bone grafts were well-maintained and stabilized with titanium plates, while the cancellous bone had undergone significant resorption and was replaced by new bone, indicative of successful natural healing.

Effect of calcium silicate-based sealer to bone tissue of mandible of rats

Purpose@#To histologically evaluate the effects of three calcium silicate-based sealers on rat mandible tissue. @*Materials and Methods@#Rats were randomly divided as follows: A group that sacrificed immediately after cavity preparation, a group that sacri-ficed two weeks after cavity preparation, a group that sacrificed two weeks after CeraSeal (CS), AH Plus Bioceramic (AHB), or OneFil (OF) sealer injection, respectively. After tissue processing for all groups, the bone tissue area (%) and the number of osteoclasts in and around the cavity were measured under a microscope. The results of each group were compared and statistical analysis was performed using one-way ANOVA and Tukey’s test. @*Results@#The formation of bone tissue and the presence of osteoclasts in the cav-ity were observed in the group that sacrificed two weeks after cavity preparation and the group sacrificed two weeks after AHB seal-er injection, and these groups showed significantly higher average bone tissue area (%) than the other groups. In the other groups, no inflammation or foreign body reaction occurred in the cavity, and no osteoclasts were observed. @*Conclusion@#All calcium silicatebased sealers used in this study showed a favorable bone tissue response when injected into the rat mandible. In particular, higher bone formation in the cavity was observed in AHB.

Thirty-year Trend in Inflammatory Bowel Disease on Jeju Island, South Korea / 대한소화기학회지

Background/Aims@#Inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), is increasing in South Korea. On the other hand, there are no reports of the incidence and prevalence of IBD specific to Jeju Island, prompting the necessity of this study. @*Methods@#In this retrospective design, the medical records of 453 patients diagnosed with IBD at Jeju National University Hospital from January 1990 to December 2019 were analyzed. @*Results@#Of the 453 IBD subjects (165 CD, 288 UC) included, the UC: CD ratio was 1.75:1. The incidence of IBD increased continuously from 0.19/105 in 1990 to 6.39/105 in 2017 and after that decreased to 4.92/105 in 2019. The male:female ratio was 2.24:1 for CD and 1.29:1 for UC. In the CD subjects, the disease activity included remission (33.3%), mild (25.5%), moderate (30.9%), and severe (6.1%). In UC subjects, the disease activity included remission (24.0%), mild (35.4%), moderate (28.8%), and severe (6.2%). According to the Montreal classification, the cases were as follows: CD: terminal ileum (22.4%), colon (9.7%), ileocolon (66.1%), and upper gastrointestinal involvement (27.3%), and perianal fistula/abscess was present in 43.6% of subjects before or at diagnosis: UC: proctitis (43.4%), left-sided colitis (29.1%), and pancolitis (23.3%) at diagnosis. @*Conclusions@#The incidence of IBD on Jeju Island has increased steadily for approximately 30 years but has exhibited a decline since 2017. Therefore, the incidence of IBD in Jeju is believed to have plateaued. Further study will be needed for clarification. (Korean J Gastroenterol 2023;81:243-252)

Nanomaterial-Based Scaffolds for Tissue Engineering Applications: A Review on Graphene, Carbon Nanotubes and Nanocellulose

Nanoscale biomaterials have garnered immense interest in the scientific community in the recent decade. This review specifically focuses on the application of three nanomaterials, i.e., graphene and its derivatives (graphene oxide, reduced graphene oxide), carbon nanotubes (CNTs) and nanocellulose (cellulose nanocrystals or CNCs and cellulose nanofibers or CNFs), in regenerating different types of tissues, including skin, cartilage, nerve, muscle and bone. Their excellent inherent (and tunable) physical, chemical, mechanical, electrical, thermal and optical properties make them suitable for a wide range of biomedical applications, including but not limited to diagnostics, therapeutics, biosensing, bioimaging, drug and gene delivery, tissue engineering and regenerative medicine. A state-of-the-art literature review of composite tissue scaffolds fabricated using these nanomaterials is provided, including the unique physicochemical properties and mechanisms that induce cell adhesion, growth, and differentiation into specific tissues. In addition, in vitro and in vivo cytotoxic effects and biodegradation behavior of these nanomaterials are presented. We also discuss challenges and gaps that still exist and need to be addressed in future research before clinical translation of these promising nanomaterials can be realized in a safe, efficacious, and economical manner.

Retrograde filling with Lid technique in periapical surgery: case report

Apical sealing with proper retrograde filling material and technique is the key factor for successful apical surgery. In order to provide impeccable apical sealing and healing, various mechanical and chemical characteristics of retrograde filling material is required.MTA has been used as the gold standard of retrograde filling due to its unprecedented advantages. As MTA has long setting time and difficult handling properties, premixed putty type bioceramic material has been newly developed. For efficient retrofilling with premixed putty type biocreamic material, ‘Lid technique’ was also proposed. The following cases present apical surgery using newly developed premixed putty type bioceramic material with Lid technique.

Intermittent Administration of Parathyroid Hormone for Orthodontic Tooth Movement in Mongrel Dogs: Preliminary Study

Purpose@#This study investigated the orthodontic tooth movement after weekly parathyroid hormone (PTH) injection in mongrel dogs and analyzes bone formation activity on the tension and pressure sides of the tooth movement in mongrel dogs. @*Materials and Methods@#Three mongrel dogs were used in this study. The first premolar was extracted and orthodontic force using 150 g of closed coil springs between the canine and second premolar was applied. The low-dose PTH group (PTH_1) and high-dose PTH group (PTH_2) received weekly injections of 1.61 μg/kg and 3.23 μg/kg of PTH, respectively. The control group received weekly injections of 1 ml of saline. Clinical, histomorphometric analysis were carried out.Result: The orthodontic tooth movement was greatest in the PTH_2 group and the lowest in the control group. Fluorescence staining images showed higher bone remodeling on the tension side of the tooth movement in the PTH_1 and PTH_2 groups. PTH_2 group showed a thicker labeling band than the PTH_1 group. PTH_2 group showed the highest mineral apposition rate and bone formation rate, followed by the PTH_1 group and the control group. @*Conclusion@#Weekly intermittent PTH injection, especially in the short-term and at higher doses with orthodontic force, successfully increased orthodontic tooth movement and bone remodeling in mongrel dogs.

Prediction of Postoperative Lung Function in Lung Cancer Patients Using Machine Learning Models / 결핵및호흡기질환

Background@#Surgical resection is the standard treatment for early-stage lung cancer. Since postoperative lung function is related to mortality, predicted postoperative lung function is used to determine the treatment modality. The aim of this study was to evaluate the predictive performance of linear regression and machine learning models. @*Methods@#We extracted data from the Clinical Data Warehouse and developed three sets: set I, the linear regression model; set II, machine learning models omitting the missing data: and set III, machine learning models imputing the missing data. Six machine learning models, the least absolute shrinkage and selection operator (LASSO), Ridge regression, ElasticNet, Random Forest, eXtreme gradient boosting (XGBoost), and the light gradient boosting machine (LightGBM) were implemented. The forced expiratory volume in 1 second measured 6 months after surgery was defined as the outcome. Five-fold cross-validation was performed for hyperparameter tuning of the machine learning models. The dataset was split into training and test datasets at a 70:30 ratio. Implementation was done after dataset splitting in set III. Predictive performance was evaluated by R2 and mean squared error (MSE) in the three sets. @*Results@#A total of 1,487 patients were included in sets I and III and 896 patients were included in set II. In set I, the R2 value was 0.27 and in set II, LightGBM was the best model with the highest R2 value of 0.5 and the lowest MSE of 154.95. In set III, LightGBM was the best model with the highest R2 value of 0.56 and the lowest MSE of 174.07. @*Conclusion@#The LightGBM model showed the best performance in predicting postoperative lung function.

Clinical and Radiological Characteristics of Lesser Trochanter Splitting Irreducible Intertrochanteric Fractures

Background@#The purpose of this study was to investigate the demographic factors and radiological characteristics of lesser trochanter splitting (LTS) irreducible intertrochanteric fractures and to report the clinical results of patients who underwent open reduction and internal fixation using dynamic hip screws (DHS). @*Methods@#Inclusion criteria were as follows: AO/Orthopedic Trauma Association type 31A1.2, a fracture line originating from the outside of the greater trochanter that passes through the lesser trochanter, and patients who were followed up for more than 1 year with a confirmed presence or absence of bone union. A total of 13 cases were identified, accounting for 3.1% (13/416 intertrochanteric fractures). Patients were classified according to posterior sagging of the distal shaft fragment relative to the headneck fragment (posterior sagging group, 6; non-sagging group, 7). Demographic data, comorbidities, injury mechanism, type of anesthesia, operation time, blood loss, tip-apex distance, reduction quality, leg length discrepancy (> 5 mm), long lesser trochanter sign, postoperative complications, and presence of bony union were obtained by reviewing medical records and radiological findings. @*Results@#The mean age of the patients was 50.4 ± 10.4 years, and 12 were men. Except for 1 case (slip down), all were induced by high-energy trauma. According to the grade of reduction quality, 5 cases (38.5%) had good reduction quality and 8 cases (61.5%) had acceptable reduction quality. There were no postoperative complications, and bony union was observed in all cases. The long lesser trochanter sign was observed in 5 cases (38.5%) and leg length discrepancy greater than 5 mm was not observed. Compared with the non-sagging group, the posterior sagging group had more head-neck fragments containing more than 1/2 of the lesser trochanter length, longer operation time, and more blood loss (p < 0.05). Compared to the non-sagging group, the posterior sagging group had worse reduction quality and more long lesser trochanter signs (p < 0.05). @*Conclusions@#Open reduction and internal fixation using DHS for the LTS irreducible intertrochanteric fractures can achieve good clinical and radiological outcomes. However, in the posterior sagging type, reduction can be more difficult with a longer operation time and higher likelihood of blood loss.

Hip Fractures in Centenarians: Functional Outcomes, Mortality, and Risk Factors from a Multicenter Cohort Study

Background@#Increasing longevity has caused the very old population to become the fastest-growing segment. The number of centenarians (over 100 years old) is increasing rapidly. Fractures in the elderly lead to excessive medical costs and decreased quality of life with socioeconomic burdens. However, little research has thoroughly examined the functional outcomes and mortality of hip fractures in centenarians. @*Methods@#This is a retrospective observational study. Sixty-eight centenarian hip fracture patients were admitted to the 10 institutions from February 2004 to December 2019. Fifty-six patients with 1-year follow-up were finally included. The following data were obtained: sex, age, body mass index, Charlson comorbidity index value on the operation day, Koval’s classification for ambulatory ability, type of fracture, the time interval from trauma to surgery, American Society of Anesthesiologists grade, surgery-related complications, and duration of hospital stay. Postoperative Koval’s classification (at 1 year after surgery) and information about death were also collected. Multivariate analysis was performed to analyze the risk factors affecting mortality 1 year after surgery. @*Results@#Mortality rates were 26.8% at 6 months and 39.3% at 1 year. The 90-day mortality was 19.6%, and one of them (2.1%) died in the hospital. The 1-year mortality rates for the community ambulatory and non-community ambulatory groups were 29% and 52%, respectively. Only 9 (16.1%) were able to walk outdoors 1 year after surgery. The remaining 47 patients (83.9%) had to stay indoors after surgery. Multivariate analysis demonstrated that the pre-injury ambulatory level (adjusted hazard ratio, 2.884; p = 0.034) was associated with the risk of mortality. @*Conclusions@#We report a 1-year mortality rate of 39.3% in centenarian patients with hip fractures. The risk factor for mortality was the pre-injury ambulatory status. This could be an important consideration in the planning of treatment for centenarian hip fracture patients.

Osteoporosis Feature Selection and Risk Prediction Model by Machine Learning Using a Cross-Sectional Database

Background@#The purpose of this study was to verify the accuracy and validity of using machine learning (ML) to select risk factors, to discriminate differences in feature selection by ML between men and women, and to develop predictive models for patients with osteoporosis in a big database. @*Methods@#The data on 968 observed features from a total of 3,484 the Korea National Health and Nutrition Examination Survey participants were collected. To find preliminary features that were well-related to osteoporosis, logistic regression, random forest, gradient boosting, adaptive boosting, and support vector machine were used. @*Results@#In osteoporosis feature selection by 5 ML models in this study, the most selected variables as risk factors in men and women were body mass index, monthly alcohol consumption, and dietary surveys. However, differences between men and women in osteoporosis feature selection by ML models were age, smoking, and blood glucose level. The receiver operating characteristic (ROC) analysis revealed that the area under the ROC curve for each ML model was not significantly different for either gender. @*Conclusions@#ML performed a feature selection of osteoporosis, considering hidden differences between men and women. The present study considers the preprocessing of input data and the feature selection process as well as the ML technique to be important factors for the accuracy of the osteoporosis prediction model.

Effect of Artificial Intelligence or Machine Learning on Prediction of Hip Fracture Risk: Systematic Review

Background@#Dual energy X-ray absorptiometry (DXA) is a preferred modality for screening or diagnosis of osteoporosis and can predict the risk of hip fracture. However, the DXA test is difficult to implement easily in some developing countries, and fractures have been observed before patients underwent DXA. The purpose of this systematic review is to search for studies that predict the risk of hip fracture using artificial intelligence (AI) or machine learning, organize the results of each study, and analyze the usefulness of this technology. @*Methods@#The PubMed, OVID Medline, Cochrane Collaboration Library, Web of Science, EMBASE, and AHRQ databases were searched including “hip fractures” AND “artificial intelligence”. @*Results@#A total of 7 studies are included in this study. The total number of subjects included in the 7 studies was 330,099. There were 3 studies that included only women, and 4 studies included both men and women. One study conducted AI training after 1:1 matching between fractured and non-fractured patients. The area under the curve of AI prediction model for hip fracture risk was 0.39 to 0.96. The accuracy of AI prediction model for hip fracture risk was 70.26% to 90%. @*Conclusions@#We believe that predicting the risk of hip fracture by the AI model will help select patients with high fracture risk among osteoporosis patients. However, to apply the AI model to the prediction of hip fracture risk in clinical situations, it is necessary to identify the characteristics of the dataset and AI model and use it after performing appropriate validation.

Salvage of a nasal chondrocutaneous flap after a traumatic avulsion injury using a combination of treatments polydeoxyribonucleotide injection, continuous non-rebreather mask oxygen therapy, and chemical leeching: a case report

Skin avulsions are severe traumatic injuries, in which sections of skin and subcutaneous tissue are torn off from the body, and the surgical management and salvage of these injuries are quite challenging due to their high morbidity and mortality. The entire or partial loss of an avulsed flap is prone to occur. If this happens, scars can be particularly conspicuous, and additional surgery, such as skin grafts or local flaps or even composite grafts, might be required. A 24-year-old male patient presented to the emergency room with a severe traumatic avulsion injury on his nose. We used a combination of three therapies to minimize the loss of the distal portion of the avulsed flap: polydeoxyribonucleotide injection, continuous non-rebreather mask oxygen therapy, and chemical leeching. We achieved complete flap salvage of the avulsed wound, and the patient showed full satisfaction in both aesthetic and functional aspects. Although this report is confined to a single case of severe avulsed injury, we suggest this triple-combination therapy as a good combined modality for maximizing the salvage of an avulsed flap on the basis of this case and a literature review.

Hybrid columellar strut using nasal crest bone of the maxilla and conchal cartilage for nasal tip stability in rhinoplasty for East Asian patients

Background@#Proper nasal tip projection and rotation are essential for an aesthetically pleasing nose. However, East Asians usually have thicker skin and underdeveloped nasal cartilage compared to Caucasians. Thus, techniques such as the septal extension graft, columellar strut graft, and L-shaped alloplastic implants have been introduced for additional nasal tip support and projection. However, no consensus exists regarding the optimal method. @*Methods@#A hybrid columellar strut made of an osteochondral graft recombined with the nasal crest of the maxilla and conchal cartilage was devised. In a cadaveric study, changes due to an external bending force of the hybrid strut and costal cartilage in the same dimension were measured. In a comparative study, we divided 20 subjects into two groups according to the material used for the columellar strut graft: a hybrid columellar strut (experimental group) and a double-layered conchal columellar strut (control group). Preoperative, 1-month postoperative, and 1-year postoperative anthropometric measurements were compared between groups. @*Results@#In the cadaveric study, the hybrid columellar strut showed superior mechanical strength. In the comparative study, the average 1-year postoperative change of the columellar labial angle was significantly smaller in the experimental group (–0.7°±1.16° vs. 2.2°±1.32°, P=0.015). The hybrid columellar strut showed superior postoperative nasal tip stability. @*Conclusions@#We devised a new hybrid columellar strut and confirmed its superior mechanical firmness and stability. Considering the suggested indications and contraindications, the hybrid columellar strut graft can be a new modality for tip plasty in East Asian rhinoplasty that can provide sufficient long-term nasal tip stability.

Fracture Liaison Service in Korea: 2022 Position Statement of the Korean Society for Bone and Mineral Research

Osteoporosis and osteoporotic fractures cause socioeconomic concerns, and medical system and policies appear insufficient to prepare for these issues in Korea, where the older adult population is rapidly increasing. Many countries around the world are already responding to osteoporosis and osteoporotic fractures by adopting fracture liaison service (FLS), and such an attempt has only begun in Korea. In this article, we introduce the operation methods for institutions implementing FLS and characteristics of services, and activities of the FLS Committee for FLS implementation in the Korean Society for Bone and Mineral Research. In addition, we hope that the current position statement will contribute to the implementation of FLS in Korea and impel policy changes to enable a multidisciplinary and integrated FLS operated under the medical system.

A Novel One-Step Knife Approach Can Reduce the Submucosal Injection Time of Endoscopic Submucosal Dissection: A SingleBlinded Randomized Multicenter Clinical Trials

Background/Aims@#Endoscopic submucosal dissection (ESD) is a curative treatment modality for early gastric neoplasms; however, ESD can be a time-consuming process. To overcome this pitfall, we developed the one-step knife (OSK) approach, which combines an endoscopic knife and injection needle on a single sheath. We aimed to evaluate whether this approach could reduce the ESD procedure time. @*Methods@#This single-blinded randomized multicenter trial at four tertiary hospitals from June 2019 to June 2020 included patients aged 19 to 85 years undergoing ESD. Patients were randomly assigned to two groups (OSK or conventional knife [CK]). The injection time, total procedure time, resected specimen size, submucosal fluid amount, degree of device satisfaction, and adverse events were evaluated and compared between groups. @*Results@#Fifty-one patients were analyzed (OSK: 25 patients and CK: 26 patients). No baseline differences were observed between groups, with the exception of a higher portion of males in the OSK group. The mean injection time was significantly reduced in the OSK group (39.0 seconds) compared to that in the CK group (87.5 seconds, p<0.001). A decrease of more than 10 minutes in the total procedure time (18.0 minutes vs 28.1 minutes, p=0.055) in the OSK group compared to the CK group was observed. Second-look esophagogastroduodenoscopy revealed two delayed bleeding cases in the OSK group that were easily controlled by endoscopic hemostasis. @*Conclusions@#OSK reduced the injection time and showed a decrease in total procedure time compared with the CK approach. OSK can be a feasible tool for ESD, especially in difficult cases.

Increased Healthcare Delays in Tuberculosis Patients During the First Wave of COVID-19 Pandemic in Korea: A Nationwide Cross-Sectional Study

Background@#The coronavirus disease 2019 (COVID-19) pandemic caused disruptions to healthcare systems, consequently endangering tuberculosis (TB) control. We investigated delays in TB treatment among notified patients during the first wave of the COVID-19 pandemic in Korea. @*Methods@#We systemically collected and analyzed data from the Korea TB cohort database from January to May 2020. Groups were categorized as ‘before-pandemic’ and ‘during-pandemic’ based on TB notification period. Presentation delay was defined as the period between initial onset of symptoms and the first hospital visit, and healthcare delay as the period between the first hospital visit and anti-TB treatment initiation. A multivariate logistic regression analysis was performed to evaluate factors associated with delays in TB treatment. @*Results@#Proportion of presentation delay > 14 days was not significantly different between two groups (48.3% vs. 43.7%, P = 0.067); however, proportion of healthcare delay > 5 days was significantly higher in the during-pandemic group (48.6% vs. 42.3%, P = 0.012). In multivariate analysis, the during-pandemic group was significantly associated with healthcare delay > 5 days (adjusted odds ratio = 0.884, 95% confidence interval = 0.715–1.094). @*Conclusion@#The COVID-19 pandemic was associated with healthcare delay of > 5 days in Korea. Public health interventions are necessary to minimize the pandemic’s impact on the national TB control project.

Efficacy of retreatment NiTi files for root canals filled with calcium silicate-based sealer

Purpose@#The efficacy of the amount of sealer in the root canal and two retreatment NiTi file systems in removing filling materials. @*Materials and Methods@#Extracted premolars with a single root canal were selected for this study. After access opening and root canal preparation up to size #40/.06, the specimens were randomly divided into four groups. Gutta percha (GP) tapers of .06 or .04 were used for each group and filled using a single-cone filling technique with CeraSeal, a calcium silicate-based sealer. Each group was retreated either using the ProTaper Universal Retreatment System (PTUR) or the Hyflex Remover (HR). The time taken to remove the filling material, the amounts of apically extruded debris, and canal cleanliness were measured and compared. @*Results@#The amount of sealer did not affect the efficiency when removing the filling materials. However, the filling material was removed faster in the HR group than in the PTUR group. Two types of NiTi files showed similar retreatment effects in the amounts of apically extruded debris and in the degree of canal cleanliness. @*Conclusion@#The amount of sealer in canal filling had no significant effect on retreatability. Retreatment with HR removed filling materials is faster than PTUR. There was no difference in other removal efficiencies according to the type of retreatment NiTi file.

Effect of storage condition of resin cement on shear bond strength of the orthodontic bracket

Purpose@#For orthodontic bracket bonding, light curing resin cement is widely used because the process is convenient, and it can be polymerized at the desired time. This study compared the difference of bonding strength of orthodontic resin cement according to storage condition. @*Materials and Methods@#After acid etching the bovine enamel surface with 37% phosphoric acid, 15 orthodontic brackets for mandible incisors were bonded with Ortho Connect and Orthomite LC according to following three conditions; 1) Immediate after 4°C refrigeration for 3 months (IR), 2) One day room temperature after 4°C refrigeration for 3 months (OR), 3) Room temperature for 3 months (RT). The shear bond strength was measured with a universal material tester and failure pattern of the specimen was observed. Two-way ANOVA and One-way ANOVA were used at the 95% significance level. @*Results@#Ortho Connect that was applied immediately after refrigeration showed the maximum shear bond strength. Orthomite that was applied immediately after refrigeration showed the lowest shear bond strength, and the group stored at room temperature for three months showed the highest shear bond strength, and the difference between the two groups was significant. @*Conclusion@#Ortho Connect can be used without worrying about bond strength even if it is used immediately after refrigeration, but Orthomite should be kept at room temperature sufficiently after refrigeration.

Design Approaches and Computational Tools for DNA Nanostructures.

Designing a structure in nanoscale with desired shape and properties has been enabled by structural DNA nanotechnology. Design strategies in this research field have evolved to interpret various aspects of increasingly more complex nanoscale assembly and to realize molecular-level functionality by exploring static to dynamic characteristics of the target structure. Computational tools have naturally been of significant interest as they are essential to achieve a fine control over both shape and physicochemical properties of the structure. Here, we review the basic design principles of structural DNA nanotechnology together with its computational analysis and design tools.