Tooth transposition is a rare dental anomaly in which two adjacent teeth develop and erupt in altered positions. It is often associated with other dental abnormalities, such as congenitally missing or peg-shaped lateral incisors. This case report presents 3 pediatric patients diagnosed with complete unilateral transposition of the maxillary canines and peg-shaped lateral incisors. In all cases, the transposed teeth were aligned in altered positions to minimize potential complications, such as root resorption. Orthodontic traction and alignment were performed, resulting in satisfactory tooth alignment without significant complications.

This retrospective study evaluated the 24-month survival rates of second primary molars after treatment of ectopic eruption of the maxillary permanent first molar with the Halterman appliance. Patients diagnosed with ectopic eruption at the Department of Pediatric Dentistry at Chosun University Dental Hospital and three private pediatric dental clinics between January 2017 and December 2021 were included. This study involved 113 children (66 boys and 47 girls) aged 5 to 9 years, utilizing electronic medical records and panoramic radiographs for evaluation. Survival analysis of second primary molars was conducted using the Kaplan-Meier method and Cox proportional hazards regression models. The findings indicated that the degree of root resorption significantly influenced survival rates, with 24-month cumulative survival rates of 90.9% for grade 1, 88.6% for grade 2, 68.9% for grade 3, and 33.3% for grade 4. The risk of premature loss was approximately 8.7 times higher in grade 4 compared to grade 1. No significant correlation was found between the survival rates and factors such as patient age, mesial angulation of the permanent first molar, or gingival emergence status of the permanent first molar. This study emphasizes the critical need to evaluate root resorption in second primary molars and to carefully consider anchorage design in the treatment of ectopically erupted permanent first molars, highlighting directions for further research.

Tooth transposition is a rare dental anomaly in which two adjacent teeth develop and erupt in altered positions. It is often associated with other dental abnormalities, such as congenitally missing or peg-shaped lateral incisors. This case report presents 3 pediatric patients diagnosed with complete unilateral transposition of the maxillary canines and peg-shaped lateral incisors. In all cases, the transposed teeth were aligned in altered positions to minimize potential complications, such as root resorption. Orthodontic traction and alignment were performed, resulting in satisfactory tooth alignment without significant complications.

This retrospective study evaluated the 24-month survival rates of second primary molars after treatment of ectopic eruption of the maxillary permanent first molar with the Halterman appliance. Patients diagnosed with ectopic eruption at the Department of Pediatric Dentistry at Chosun University Dental Hospital and three private pediatric dental clinics between January 2017 and December 2021 were included. This study involved 113 children (66 boys and 47 girls) aged 5 to 9 years, utilizing electronic medical records and panoramic radiographs for evaluation. Survival analysis of second primary molars was conducted using the Kaplan-Meier method and Cox proportional hazards regression models. The findings indicated that the degree of root resorption significantly influenced survival rates, with 24-month cumulative survival rates of 90.9% for grade 1, 88.6% for grade 2, 68.9% for grade 3, and 33.3% for grade 4. The risk of premature loss was approximately 8.7 times higher in grade 4 compared to grade 1. No significant correlation was found between the survival rates and factors such as patient age, mesial angulation of the permanent first molar, or gingival emergence status of the permanent first molar. This study emphasizes the critical need to evaluate root resorption in second primary molars and to carefully consider anchorage design in the treatment of ectopically erupted permanent first molars, highlighting directions for further research.

Tooth transposition is a rare dental anomaly in which two adjacent teeth develop and erupt in altered positions. It is often associated with other dental abnormalities, such as congenitally missing or peg-shaped lateral incisors. This case report presents 3 pediatric patients diagnosed with complete unilateral transposition of the maxillary canines and peg-shaped lateral incisors. In all cases, the transposed teeth were aligned in altered positions to minimize potential complications, such as root resorption. Orthodontic traction and alignment were performed, resulting in satisfactory tooth alignment without significant complications.

This retrospective study evaluated the 24-month survival rates of second primary molars after treatment of ectopic eruption of the maxillary permanent first molar with the Halterman appliance. Patients diagnosed with ectopic eruption at the Department of Pediatric Dentistry at Chosun University Dental Hospital and three private pediatric dental clinics between January 2017 and December 2021 were included. This study involved 113 children (66 boys and 47 girls) aged 5 to 9 years, utilizing electronic medical records and panoramic radiographs for evaluation. Survival analysis of second primary molars was conducted using the Kaplan-Meier method and Cox proportional hazards regression models. The findings indicated that the degree of root resorption significantly influenced survival rates, with 24-month cumulative survival rates of 90.9% for grade 1, 88.6% for grade 2, 68.9% for grade 3, and 33.3% for grade 4. The risk of premature loss was approximately 8.7 times higher in grade 4 compared to grade 1. No significant correlation was found between the survival rates and factors such as patient age, mesial angulation of the permanent first molar, or gingival emergence status of the permanent first molar. This study emphasizes the critical need to evaluate root resorption in second primary molars and to carefully consider anchorage design in the treatment of ectopically erupted permanent first molars, highlighting directions for further research.

BACKGROUND: Retinal degenerative disease (RDD), one of the most common causes of blindness, is predominantly caused by the gradual death of retinal pigment epithelial cells (RPEs) and photoreceptors due to various causes. Cell-based therapies, such as stem cell implantation, have been developed for the treatment of RDD, but potential risks, including teratogenicity and immune reactions, have hampered their clinical application. Stem cell-derived extracellular vesicles (EVs) have recently emerged as a cell-free alternative therapeutic strategy; however, additional invasiveness and low yield of the stem cell extraction process is problematic. METHODS: To overcome these limitations, we developed therapeutic EVs for the treatment of RDD which were extracted from tonsil-derived mesenchymal stem cells obtained from human tonsil tissue discarded as medical waste following tonsillectomy (T-MSC EVs). To verify the biocompatibility and cytoprotective effect of T-MSC EVs, we measured cell viability by co-culture with human RPE without or with toxic all-trans-retinal. To elucidate the cytoprotective mechanism of T-MSC EVs, we performed transcriptome sequencing using RNA extracted from RPEs. The in vivo protective effect of T-MSC EVs was evaluated using Pde6b gene knockout rats as an animal model of retinitis pigmentosa. RESULTS: T-MSC EVs showed high biocompatibility and the human pigment epithelial cells were significantly protected in the presence of T-MSC EVs from the toxic effect of all-trans-retinal. In addition, T-MSC EVs showed a dosedependent cell death-delaying effect in real-time quantification of cell death. Transcriptome sequencing analysis revealed that the efficient ability of T-MSC EVs to regulate intracellular oxidative stress may be one of the reasons explaining their excellent cytoprotective effect. Additionally, intravitreally injected T-MSC EVs had an inhibitory effect on the destruction of the outer nuclear layer in the Pde6b gene knockout rat. CONCLUSIONS Together, the results of this study indicate the preventive and therapeutic effects of T-MSC EVs during the initiation and development of retinal degeneration, which may be a beneficial alternative for the treatment of RDD.

Background: Leukocyte reduction filters (LRF) and blood transfusion sets (BTS) are frequently used medical devices to prevent blood transfusion-related adverse reactions. This study attempted to analyze these medical devices related adverse events reported by an institution for 10 years and to understand the status of such reports in Korea and the United States (U.S.). Methods: From January 2013 to October 2022, adverse events reported at Soonchunhyang university Bucheon hospital (SCHBC) were analyzed. From 2016 to 2022, adverse events registered in the Korean Medical Device Information Portal and the Total Product Life Cycle (TPLC) database of the U.S. were collected and evaluated using the International Medical Device Regulators Forum (IMDRF) code for medical device problems, clinical signs, and symptoms or conditions. Results: A total of 12, 47, and 1,422 events were identified in SCHBC, Korea, and the U.S., respectively. The medical device problems reported in BTS included fluid leakage, breakage, disconnection, and no flow. In LRF, device or reagent problems, coagulation of device or device components, and filtration problems were reported. Most of the clinical signs and symptoms or conditions were not applicable (98.1%, 1,453/1,481), but hypotension and hemolysis were reported in LRF. Conclusion To improve the safety of transfusion-related medical devices such as LRF and BTS, proper attention needs to be paid to adverse events and all medical institutions should participate in the reporting of such events.The various adverse events and associated IMDRF codes included in this study would help enable reporting of adverse events and improve patient safety.