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: Large language models (LLMs) have the potential for clinical decision support; however, their use in specific tasks, such as determining the RhD blood type for transfusion, remains underexplored. Therefore, we evaluated the accuracy of six LLMs in addressing RhD blood type-related issues in Korean healthcare. Methods: Fifteen multiple-choice and true/false questions, based on real-world transfusion scenarios and reviewed by specialists, were developed. The questions were administered twice to six LLMs (Clova X, Gemini 1.0, Gemini 1.5, ChatGPT-3.5, GPT-4.0, and GPT-4o) in both Korean and English. Results were compared against the performance of 22 transfusion medicine experts. For particularly challenging questions, prompt engineering was applied, and the questions were reevaluated. Results: GPT-4o demonstrated the highest accuracy rate in Korean (0.6), with significant differences compared with those of Clova X and Gemini (P < 0.05). In English, the results were similar across all models. The transfusion experts achieved a higher accuracy rate (0.8). Among the five questions subjected to prompt engineering, only GPT-4o correctly responded to one, whereas the other models failed. All LLM models changed their responses or did not respond when the same question was repeated. Conclusions GPT-4o showed the best overall performance among the models tested and may be beneficial in RhD blood product transfusion decision-making. However, its performance suggests that it may serve best in a supportive role rather than as a primary decision-making tool.

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.