1.Effect of a miniscrew surgical guide on the success rate and root proximity of orthodontic miniscrews:A retrospective cohort study
Eun-Hack ANDREW CHOI ; Dasomi KIM ; Liu JING ; Hyung-Seog YU ; Sung-Hwan CHOI ; Jung-Yul CHA
The Korean Journal of Orthodontics 2025;55(3):167-175
Objective:
To assess the success rate and proximity of miniscrews to the root using surgical guides produced by integrating data obtained from conebeam computed tomography and intraoral scanned models.
Methods:
This retrospective study involved 113 patients (224 miniscrews) who underwent miniscrew placement as part of their orthodontic treatment. Two operators placed miniscrews between the buccal alveolar bone of each patient and assessed initial stability by measuring the Periotest value (PTV) and insertion torque (IT). Patients were divided into two groups based on the miniscrew insertion method: manual group (MG) and surgical guide group (SG). Root proximity was assessed using periapical radiography, and miniscrews that remained in place for over 6 months were considered successful.
Results:
There was a statistically significant difference in the Kaplan–Meier survival curves between the groups (P < 0.05). The success rates of the miniscrews were 79.1% and 90.5% for the MG and SG, respectively (P < 0.05). The root contact rate also differed significantly between the groups (MG, 17.5%; SG, 0.1%; P < 0.001). However, the PTV and IT did not show significant differences between the groups.
Conclusions
Proximity to the root and utilization of surgical guides have the most direct impact on the success rate of miniscrews. Root proximity can be effectively reduced using surgical guides. Therefore, the use of a miniscrew surgical guide is recommended to increase the success rate of miniscrews as stable anchorage devices, particularly in cases with narrow interradicular space.
2.Study Protocol of Expanded Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro-EXP)
Jae Hoon MOON ; Eun Kyung LEE ; Wonjae CHA ; Young Jun CHAI ; Sun Wook CHO ; June Young CHOI ; Sung Yong CHOI ; A Jung CHU ; Eun-Jae CHUNG ; Yul HWANGBO ; Woo-Jin JEONG ; Yuh-Seog JUNG ; Kyungsik KIM ; Min Joo KIM ; Su-jin KIM ; Woochul KIM ; Yoo Hyung KIM ; Chang Yoon LEE ; Ji Ye LEE ; Kyu Eun LEE ; Young Ki LEE ; Hunjong LIM ; Do Joon PARK ; Sue K. PARK ; Chang Hwan RYU ; Junsun RYU ; Jungirl SEOK ; Young Shin SONG ; Ka Hee YI ; Hyeong Won YU ; Eleanor WHITE ; Katerina MASTROCOSTAS ; Roderick J. CLIFTON-BLIGH ; Anthony GLOVER ; Matti L. GILD ; Ji-hoon KIM ; Young Joo PARK
Endocrinology and Metabolism 2025;40(2):236-246
Background:
Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making.
Methods:
This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes.
Conclusion
This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.
3.Effect of a miniscrew surgical guide on the success rate and root proximity of orthodontic miniscrews:A retrospective cohort study
Eun-Hack ANDREW CHOI ; Dasomi KIM ; Liu JING ; Hyung-Seog YU ; Sung-Hwan CHOI ; Jung-Yul CHA
The Korean Journal of Orthodontics 2025;55(3):167-175
Objective:
To assess the success rate and proximity of miniscrews to the root using surgical guides produced by integrating data obtained from conebeam computed tomography and intraoral scanned models.
Methods:
This retrospective study involved 113 patients (224 miniscrews) who underwent miniscrew placement as part of their orthodontic treatment. Two operators placed miniscrews between the buccal alveolar bone of each patient and assessed initial stability by measuring the Periotest value (PTV) and insertion torque (IT). Patients were divided into two groups based on the miniscrew insertion method: manual group (MG) and surgical guide group (SG). Root proximity was assessed using periapical radiography, and miniscrews that remained in place for over 6 months were considered successful.
Results:
There was a statistically significant difference in the Kaplan–Meier survival curves between the groups (P < 0.05). The success rates of the miniscrews were 79.1% and 90.5% for the MG and SG, respectively (P < 0.05). The root contact rate also differed significantly between the groups (MG, 17.5%; SG, 0.1%; P < 0.001). However, the PTV and IT did not show significant differences between the groups.
Conclusions
Proximity to the root and utilization of surgical guides have the most direct impact on the success rate of miniscrews. Root proximity can be effectively reduced using surgical guides. Therefore, the use of a miniscrew surgical guide is recommended to increase the success rate of miniscrews as stable anchorage devices, particularly in cases with narrow interradicular space.
4.Effect of a miniscrew surgical guide on the success rate and root proximity of orthodontic miniscrews:A retrospective cohort study
Eun-Hack ANDREW CHOI ; Dasomi KIM ; Liu JING ; Hyung-Seog YU ; Sung-Hwan CHOI ; Jung-Yul CHA
The Korean Journal of Orthodontics 2025;55(3):167-175
Objective:
To assess the success rate and proximity of miniscrews to the root using surgical guides produced by integrating data obtained from conebeam computed tomography and intraoral scanned models.
Methods:
This retrospective study involved 113 patients (224 miniscrews) who underwent miniscrew placement as part of their orthodontic treatment. Two operators placed miniscrews between the buccal alveolar bone of each patient and assessed initial stability by measuring the Periotest value (PTV) and insertion torque (IT). Patients were divided into two groups based on the miniscrew insertion method: manual group (MG) and surgical guide group (SG). Root proximity was assessed using periapical radiography, and miniscrews that remained in place for over 6 months were considered successful.
Results:
There was a statistically significant difference in the Kaplan–Meier survival curves between the groups (P < 0.05). The success rates of the miniscrews were 79.1% and 90.5% for the MG and SG, respectively (P < 0.05). The root contact rate also differed significantly between the groups (MG, 17.5%; SG, 0.1%; P < 0.001). However, the PTV and IT did not show significant differences between the groups.
Conclusions
Proximity to the root and utilization of surgical guides have the most direct impact on the success rate of miniscrews. Root proximity can be effectively reduced using surgical guides. Therefore, the use of a miniscrew surgical guide is recommended to increase the success rate of miniscrews as stable anchorage devices, particularly in cases with narrow interradicular space.
5.Study Protocol of Expanded Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro-EXP)
Jae Hoon MOON ; Eun Kyung LEE ; Wonjae CHA ; Young Jun CHAI ; Sun Wook CHO ; June Young CHOI ; Sung Yong CHOI ; A Jung CHU ; Eun-Jae CHUNG ; Yul HWANGBO ; Woo-Jin JEONG ; Yuh-Seog JUNG ; Kyungsik KIM ; Min Joo KIM ; Su-jin KIM ; Woochul KIM ; Yoo Hyung KIM ; Chang Yoon LEE ; Ji Ye LEE ; Kyu Eun LEE ; Young Ki LEE ; Hunjong LIM ; Do Joon PARK ; Sue K. PARK ; Chang Hwan RYU ; Junsun RYU ; Jungirl SEOK ; Young Shin SONG ; Ka Hee YI ; Hyeong Won YU ; Eleanor WHITE ; Katerina MASTROCOSTAS ; Roderick J. CLIFTON-BLIGH ; Anthony GLOVER ; Matti L. GILD ; Ji-hoon KIM ; Young Joo PARK
Endocrinology and Metabolism 2025;40(2):236-246
Background:
Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making.
Methods:
This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes.
Conclusion
This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.
6.Study Protocol of Expanded Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro-EXP)
Jae Hoon MOON ; Eun Kyung LEE ; Wonjae CHA ; Young Jun CHAI ; Sun Wook CHO ; June Young CHOI ; Sung Yong CHOI ; A Jung CHU ; Eun-Jae CHUNG ; Yul HWANGBO ; Woo-Jin JEONG ; Yuh-Seog JUNG ; Kyungsik KIM ; Min Joo KIM ; Su-jin KIM ; Woochul KIM ; Yoo Hyung KIM ; Chang Yoon LEE ; Ji Ye LEE ; Kyu Eun LEE ; Young Ki LEE ; Hunjong LIM ; Do Joon PARK ; Sue K. PARK ; Chang Hwan RYU ; Junsun RYU ; Jungirl SEOK ; Young Shin SONG ; Ka Hee YI ; Hyeong Won YU ; Eleanor WHITE ; Katerina MASTROCOSTAS ; Roderick J. CLIFTON-BLIGH ; Anthony GLOVER ; Matti L. GILD ; Ji-hoon KIM ; Young Joo PARK
Endocrinology and Metabolism 2025;40(2):236-246
Background:
Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making.
Methods:
This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes.
Conclusion
This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.
7.Effect of a miniscrew surgical guide on the success rate and root proximity of orthodontic miniscrews:A retrospective cohort study
Eun-Hack ANDREW CHOI ; Dasomi KIM ; Liu JING ; Hyung-Seog YU ; Sung-Hwan CHOI ; Jung-Yul CHA
The Korean Journal of Orthodontics 2025;55(3):167-175
Objective:
To assess the success rate and proximity of miniscrews to the root using surgical guides produced by integrating data obtained from conebeam computed tomography and intraoral scanned models.
Methods:
This retrospective study involved 113 patients (224 miniscrews) who underwent miniscrew placement as part of their orthodontic treatment. Two operators placed miniscrews between the buccal alveolar bone of each patient and assessed initial stability by measuring the Periotest value (PTV) and insertion torque (IT). Patients were divided into two groups based on the miniscrew insertion method: manual group (MG) and surgical guide group (SG). Root proximity was assessed using periapical radiography, and miniscrews that remained in place for over 6 months were considered successful.
Results:
There was a statistically significant difference in the Kaplan–Meier survival curves between the groups (P < 0.05). The success rates of the miniscrews were 79.1% and 90.5% for the MG and SG, respectively (P < 0.05). The root contact rate also differed significantly between the groups (MG, 17.5%; SG, 0.1%; P < 0.001). However, the PTV and IT did not show significant differences between the groups.
Conclusions
Proximity to the root and utilization of surgical guides have the most direct impact on the success rate of miniscrews. Root proximity can be effectively reduced using surgical guides. Therefore, the use of a miniscrew surgical guide is recommended to increase the success rate of miniscrews as stable anchorage devices, particularly in cases with narrow interradicular space.
8.Study Protocol of Expanded Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro-EXP)
Jae Hoon MOON ; Eun Kyung LEE ; Wonjae CHA ; Young Jun CHAI ; Sun Wook CHO ; June Young CHOI ; Sung Yong CHOI ; A Jung CHU ; Eun-Jae CHUNG ; Yul HWANGBO ; Woo-Jin JEONG ; Yuh-Seog JUNG ; Kyungsik KIM ; Min Joo KIM ; Su-jin KIM ; Woochul KIM ; Yoo Hyung KIM ; Chang Yoon LEE ; Ji Ye LEE ; Kyu Eun LEE ; Young Ki LEE ; Hunjong LIM ; Do Joon PARK ; Sue K. PARK ; Chang Hwan RYU ; Junsun RYU ; Jungirl SEOK ; Young Shin SONG ; Ka Hee YI ; Hyeong Won YU ; Eleanor WHITE ; Katerina MASTROCOSTAS ; Roderick J. CLIFTON-BLIGH ; Anthony GLOVER ; Matti L. GILD ; Ji-hoon KIM ; Young Joo PARK
Endocrinology and Metabolism 2025;40(2):236-246
Background:
Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making.
Methods:
This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes.
Conclusion
This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.
9.Effect of a miniscrew surgical guide on the success rate and root proximity of orthodontic miniscrews:A retrospective cohort study
Eun-Hack ANDREW CHOI ; Dasomi KIM ; Liu JING ; Hyung-Seog YU ; Sung-Hwan CHOI ; Jung-Yul CHA
The Korean Journal of Orthodontics 2025;55(3):167-175
Objective:
To assess the success rate and proximity of miniscrews to the root using surgical guides produced by integrating data obtained from conebeam computed tomography and intraoral scanned models.
Methods:
This retrospective study involved 113 patients (224 miniscrews) who underwent miniscrew placement as part of their orthodontic treatment. Two operators placed miniscrews between the buccal alveolar bone of each patient and assessed initial stability by measuring the Periotest value (PTV) and insertion torque (IT). Patients were divided into two groups based on the miniscrew insertion method: manual group (MG) and surgical guide group (SG). Root proximity was assessed using periapical radiography, and miniscrews that remained in place for over 6 months were considered successful.
Results:
There was a statistically significant difference in the Kaplan–Meier survival curves between the groups (P < 0.05). The success rates of the miniscrews were 79.1% and 90.5% for the MG and SG, respectively (P < 0.05). The root contact rate also differed significantly between the groups (MG, 17.5%; SG, 0.1%; P < 0.001). However, the PTV and IT did not show significant differences between the groups.
Conclusions
Proximity to the root and utilization of surgical guides have the most direct impact on the success rate of miniscrews. Root proximity can be effectively reduced using surgical guides. Therefore, the use of a miniscrew surgical guide is recommended to increase the success rate of miniscrews as stable anchorage devices, particularly in cases with narrow interradicular space.
10.Comparison of soft tissue changes between incisor tipping and translation after premolar extraction
Wonkyeong BAIK ; Sung-Hwan CHOI ; Jung-Yul CHA ; Hyung-Seog YU ; Kee-Joon LEE
The Korean Journal of Orthodontics 2022;52(1):42-52
Objective:
This study compared soft tissue changes after extraction of the four premolars followed by maximum retraction of the anterior teeth according to the type of anterior teeth movement: tipping and translation.
Methods:
Patients who had undergone orthodontic treatment involving the extraction of four premolars were retrospectively selected and divided into either the tipping (n = 27) or translation (n = 26) groups based on the retraction of the incisor root apex and the axis changes of the incisors during the treatment period. Lateral pre- and post-treatment cephalograms were analyzed.
Results:
There were no significant differences between the tipping and translation groups before treatment. The retraction amounts of the root apex of the upper and lower incisors in the tipping group were 0.33 and 0.26 mm, respectively, and 5.02 and 5.31 mm, respectively, in the translation group (p < 0.001). The posterior movements of soft tissue points A and B in the tipping group were 0.61 and 1.25 mm, respectively, and 1.10 and 3.25 mm, respectively, in the translation group (p < 0.01). The mentolabial sulcus angle increased by 5.89° in the tipping group, whereas it decreased by 8.13° in the translation group (p < 0.001).
Conclusions
An increased amount of retraction of the incisor root apex led to the increased posterior movement of soft tissue points A and B, and this appeared more distinct in cases involving the lower incisor and lower lip.

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