1.Long-term clinical and radiographic outcomes of a bone-level, 2-piece, internal connection implant system with coronal microthreads over 10years of follow-up: a retrospective clinical study
Young Woo SONG ; Seung Ha YOO ; Jin-Young PARK ; Jae-Kook CHA ; Jeong-Won PAIK ; Jung-Seok LEE ; Daniel S. THOMA ; Ui-Won JUNG
Journal of Periodontal & Implant Science 2025;55(2):153-166
Purpose:
This study retrospectively investigated the long-term clinical and radiographic outcomes of a bone-level type, 2-piece, internal connection dental implant system characterized by coronal microthreads.
Methods:
A total of 872 implants placed in 284 patients were selected from 1,845 implants placed in 691 patients by experienced periodontists at Yonsei University Dental Hospital.These selected implants had been followed up for over 10 years and were included in the present study. A statistical evaluation of implant survival and treatment success, based on changes in marginal bone levels, was conducted using electronic records and consecutively taken radiographs.
Results:
Over a follow-up period of 12.3±2.0 years, 830 of the 872 implants remained intact, yielding a cumulative survival rate of 95.2% at the implant level and 88.4% at the patient level.The cumulative treatment success rates, characterized by marginal bone loss of less than 2 mm, stood at 87.0% for implants and 76.1% for patients. Among the 830 surviving implants, 113 fixtures were classified as ailing, with an average marginal bone loss of 4.09±1.44 mm.Cox regression analysis revealed that implants 8 mm in length or shorter were significantly more likely to fail or experience pathologic marginal bone resorption, with hazard ratios of 3.71 and 2.00, respectively (P<0.05).
Conclusions
The survival and treatment success of the investigated microthreaded, bone-level, 2-piece, internal connection implants were acceptable over a follow-up period exceeding 10 years. However, shorter dental implants exhibited a higher propensity for failure and excessive marginal bone loss.
2.Consensus statement on peri-implant disease from the Korean Academy of Periodontology
Young Woo SONG ; Yun-Jeong KIM ; Shin-Young PARK ; Jae-Kook CHA ; Hyo-Jung LEE ; Seung-Min YANG ; Jun-Beom PARK ; Ki-Tae KOO
Journal of Periodontal & Implant Science 2025;55(4):247-254
This consensus report presents the first official position statement of the Korean Academy of Periodontology on peri-implant diseases, issued in response to South Korea’s rapidly aging population and the associated rise in peri-implant disease management. It reviews the prevalence, classification, and definition of peri-implant diseases, emphasizing that these conditions progress more aggressively and unpredictably than periodontal diseases.The report also identifies systemic and local risk indicators, diagnostic criteria, and evidencebased treatment protocols for peri-implant mucositis and peri-implantitis, integrating international standards with Korea-specific clinical data. Clinical recommendations include structured maintenance programs, risk-based recall intervals, and patient education, with the goal of reducing disease recurrence and improving long-term implant success.
5.Comparing the clinical effects of local administration of minocycline ointment and doxycycline solution in the treatment of acute periodontal abscesses: a retrospective clinical study
DongYeol JUNG ; Jae-Kook CHA ; Young-Taek KIM ; Chang-Sung KIM
Journal of Periodontal & Implant Science 2024;54(3):149-160
Purpose:
The objective of this retrospective clinical study was to provide evidence supporting the adjunctive local application of doxycycline solution or minocycline ointment, in conjunction with drainage, for the treatment of acute periodontal abscesses.
Methods:
The study included 63 patients who had received treatment for acute periodontal abscesses through drainage supplemented with 1 of 3 types of adjunctive medications during their initial visit (visit 1; baseline): 1) saline irrigation (the control group), 2) 2% minocycline ointment (the TM group), or 3) 300 mg/mL doxycycline irrigation (the TD group). The same adjunctive medication was administered at visit 2, which took place 1 week after visit 1. Probing depth (PD), bleeding on probing (BOP), plaque index, gingival recession, clinical attachment level, and tooth mobility were clinically evaluated at visits 1, 2, and a third visit (visit 3; 4 weeks after visit 1). Statistical significance was considered to be indicated by P values <0.05.
Results:
By visit 3, all clinical indices and tooth mobility had significantly decreased in each group. At this visit, PD and BOP on the abscess side were significantly lower in the TM and TD groups compared to the control group. The TD group showed a significantly greater improvement than the TM group, with mean PD reductions of 1.09 mm in the control group, 1.88 mm in the TM group, and 2.88 mm in the TD group. Similarly, mean BOP reductions were 45% in the control group, 73.02% in the TM group, and 95.45% in the TD group.
Conclusions
Local and adjunctive administration of doxycycline and minocycline in combination with drainage exhibited clinical advantages over drainage alone in improving PD and BOP. Notably, a doxycycline solution of 300 mg/mL was more effective than a 2% minocycline ointment.
6.Periosteum-attached Autogenous Block Bone Graft with Simultaneous Implant Placement on the Anterior Maxilla: A Case Report
Seung-Hyun PARK ; Jongseung KIM ; Ui-Won JUNG ; Jae-Kook CHA
Journal of Korean Dental Science 2024;17(2):64-74
This case report presents the long-term radiographic outcomes of a novel approach for simultaneous lateral augmentation and implant surgery. A 60-year-old male patient who required tooth extraction of the maxillary central and lateral incisors due to trauma visited the clinic. After tooth extraction, severe horizontal and vertical deficiencies occurred owing to atrophy of the alveolar ridge, and a simultaneous guided bone regeneration (GBR) procedure was planned along with the installation of two implants. In the present case, a modification of the conventional ‘sandwich technique’ was used by placing the mixture of autogenous bone chips and xenografts at the outermost layer to maximize the osteogenic potential at the coronal part of augmentation while applying solely xenografts at the inner layer. To enhance volumetric stability, an autogenous block of periosteum harvested from the maxillary tuberosity was incorporated between the two layers. Cone-beam computed tomography was performed at baseline and 3 years after the surgery to compare radiographic outcomes. Dehiscence after fixture installation was successfully observed at the re-entry of the surgery site. Three years after the surgery, average horizontal bone gains of 6.11 mm and 4.12 mm were observed in the maxillary central and lateral incisor areas, respectively. Healthy peri-implant mucosa and well maintained marginal bone levels were observed 8 years after the surgery, meeting the criteria for implant success. The findings of this case suggest that a substantial amount of horizontal bone gain can be obtained with a layered approach using autogenous bone materials and xenografts, highlighting the advantages of incorporating autogenous blocks into the simultaneous GBR procedure.
7.Expert opinion on evidence after 2020 Korean Cardiopulmonary Resuscitation Guidelines
Sung Phil CHUNG ; Youdong SOHN ; Jisook LEE ; Youngsuk CHO ; Kyoung-Chul CHA ; Ju Sun HEO ; Ai-Rhan Ellen KIM ; Jae Guk KIM ; Han-Suk KIM ; Hyungoo SHIN ; Chiwon AHN ; Ho Geol WOO ; Byung Kook LEE ; Yong Soo JANG ; Yu Hyeon CHOI ; Sung Oh HWANG ;
Journal of the Korean Society of Emergency Medicine 2023;34(4):287-296
Considerable evidence has been published since the 2020 Korean Cardiopulmonary Resuscitation Guidelines were reported. The International Liaison Committee on Resuscitation (ILCOR) also publishes the Consensus on CPR and Emergency Cardiovascular Care Science with Treatment Recommendations (CoSTR) summary annually. This review provides expert opinions by reviewing the recent evidence on CPR and ILCOR treatment recommendations. The authors reviewed the CoSTR summary published by ILCOR in 2021 and 2022. PICO (population, intervention, comparator, outcome) questions for each topic were reviewed using a systemic or scoping review methodology. Two experts were appointed for each question and reviewed the topic independently. Topics suggested by the reviewers for revision or additional description of the guidelines were discussed at a consensus conference. Forty-three questions were reviewed, including 15 on basic life support, seven on advanced life support, two on pediatric life support, 11 on neonatal life support, six on education and teams, one on first aid, and one related to coronavirus disease 2019 (COVID-19). Finally, the current Korean CPR Guideline was maintained for 28 questions, and expert opinions were suggested for 15 questions.
8.The current status and outcomes of in-hospital P2Y12 receptor inhibitor switching in Korean patients with acute myocardial infarction
Keun-Ho PARK ; Myung Ho JEONG ; Hyun Kuk KIM ; Young-Jae KI ; Sung Soo KIM ; Youngkeun AHN ; Hyun Yi KOOK ; Hyo-Soo KIM ; Hyeon Cheol GWON ; Ki Bae SEUNG ; Seung Woon RHA ; Shung Chull CHAE ; Chong Jin KIM ; Kwang Soo CHA ; Jong Seon PARK ; Jung Han YOON ; Jei Keon CHAE ; Seung Jae JOO ; Dong-Joo CHOI ; Seung Ho HUR ; In Whan SEONG ; Myeong Chan CHO ; Doo Il KIM ; Seok Kyu OH ; Tae Hoon AHN ; Jin Yong HWANG ;
The Korean Journal of Internal Medicine 2022;37(2):350-365
Background/Aims:
While switching strategies of P2Y12 receptor inhibitors (RIs) have sometimes been used in acute myocardial infarction (AMI) patients, the current status of in-hospital P2Y12RI switching remains unknown.
Methods:
Overall, 8,476 AMI patients who underwent successful revascularization from Korea Acute Myocardial Infarction Registry-National Institute of Health (KAMIR-NIH) were divided according to in-hospital P2Y12RI strategies, and net adverse cardiovascular events (NACEs), defined as a composite of cardiac death, non-fatal myocardial infarction (MI), stroke, or thrombolysis in myocardial infarction (TIMI) major bleeding during hospitalization were compared.
Results:
Patients with in-hospital P2Y12RI switching accounted for 16.5%, of which 867 patients were switched from clopidogrel to potent P2Y12RI (C-P) and 532 patients from potent P2Y12RI to clopidogrel (P-C). There were no differences in NACEs among the unchanged clopidogrel, the unchanged potent P2Y12RIs, and the P2Y12RI switching groups. However, compared to the unchanged clopidogrel group, the C-P group had a higher incidence of non-fatal MI, and the P-C group had a higher incidence of TIMI major bleeding. In clinical events of in-hospital P2Y12RI switching, 90.9% of non-fatal MI occurred during pre-switching clopidogrel administration, 60.7% of TIMI major bleeding was related to pre-switching P2Y12RIs, and 71.4% of TIMI major bleeding was related to potent P2Y12RIs. Only 21.6% of the P2Y12RI switching group switched to P2Y12RIs after a loading dose (LD); however, there were no differences in clinical events between patients with and without LD.
Conclusions
In-hospital P2Y12RI switching occurred occasionally, but had relatively similar clinical outcomes compared to unchanged P2Y12RIs in Korean AMI patients. Non-fatal MI and bleeding appeared to be mainly related to pre-switching P2Y12RIs.
9.Utility of Direct Peroral Cholangioscopy Using a Multibending Ultraslim Endoscope for Difficult Common Bile Duct Stones
Won Myung LEE ; Jong Ho MOON ; Yun Nah LEE ; Il Sang SHIN ; Tae Hoon LEE ; Jae Kook YANG ; Sang-Woo CHA ; Young Deok CHO ; Sang-Heum PARK
Gut and Liver 2022;16(4):599-605
Background/Aims:
Treatment options for difficult bile duct stones are limited. Direct peroral cholangioscopy (POC)-guided lithotripsy may be an option. A newly developed multibending (MB) ultraslim endoscope has several structural features optimized for direct POC. We evaluated the utility of direct POC using an MB ultraslim endoscope for lithotripsy in patients with difficult bile duct stones.
Methods:
Twenty patients with difficult bile duct stones, in whom stone removal using conventional endoscopic methods, including mechanical lithotripsy, had failed were enrolled from March 2018 to August 2019. Direct POC-guided lithotripsy was performed by electrohydraulic lithotripsy or laser lithotripsy. The primary outcome was complete ductal clearance, defined as the retrieval of all bile duct stones after lithotripsy confirmed by balloon-occluded cholangiography and/or direct POC.
Results:
The technical success rate of direct POC was 100% (20/20), and the free-hand insertion rate was 95% (19/20). Direct POC-guided lithotripsy, attempted by electrohydraulic lithotripsy in nine patients (45%) and laser lithotripsy in 11 patients (55%), was successful in 95% (19/20) of the patients. Complete ductal clearance after direct POC-guided lithotripsy was achieved in 95% (19/20) of patients. Patients required a median of 2 (range, 1–3) endoscopic retrograde cholangiopancreatography sessions for complete stone removal. Adverse event was observed in one patient (5%) with hemobilia and was treated conservatively.
Conclusions
Direct POC using an MB ultraslim endoscope was safe and effective for lithotripsy in patients with difficult bile duct stones.
10.Decellularized Non-cross-linked Collagen Membranes for Guided Bone Regeneration in Rabbit Calvarial Defects
Su-Hee JEON ; Da-Na LEE ; Young-Wook SEO ; Jin-Young PARK ; Jeong-Won PAIK ; Jae-Kook CHA ; Seong-Ho CHOI
Journal of Korean Dental Science 2022;15(1):51-60
Purpose:
The aim of this study was to evaluate the bio-durability and bone regeneration capacity of the non-crosslinked collagen membrane in rabbit calvarial defect models.
Materials and Methods:
Four circular defects with 8 mm diameter were made in each of calvarium of 10 male rabbits. The following groups was randomly assigned to each defect - 1) Control, 2) membrane group containing noncross-linked collagen membrane only (M), 3) bone graft group (B), 4) bone graft with membrane group (B+M). Animals were sacrificed and samples were harvested at 2 weeks (n=5) and 8 weeks (n=5). Histologic sections were prepared and histomorphometric analysis was performed.Result: Histologic results showed well adaptation of the non-cross-linked membrane on each defect and normal healing response at 2 weeks. At 8 weeks, the membranes were partially biodegraded. Histomorphometrically, B and B+M group showed the significantly greater total augmented area (B+M group, 10.44±1.49, P=0.016; B group, 9.13±0.53, P=0.032) and new bone formation (B+M group, 2.89±0.93, P=0.008; B group, 2.85±1.15, P=0.008) compared to control group. Collapsing of the central portion of the membrane, membrane group showed greater value in new bone formation at 8 weeks (1.78±0.68, P=0.032).
Conclusion
Within the limitations of this study, the non-cross-linked collagen membrane fabricated using the improved decellularized method was shown to be effective for the regeneration of calvarial bone defects. In addition, prolonged barrier function might be provided using this collagen membrane.

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