• Clinics in Shoulder and Elbow
• /
• v.26 no.4
• /
• pp.445-454
• /
• 2023

The Latarjet procedure is a surgical procedure that can effectively restore glenohumeral stability, especially in patients with anterior shoulder instability and glenoid bone loss. Many studies have shown comparable clinical outcomes between patients undergoing the arthroscopic Latarjet procedure and those undergoing traditional open methods or other glenohumeral joint stabilization procedures. However, the arthroscopic Latarjet procedure is a challenging technique due to the unfamiliar portal placements, proximity of neurovascular structures, and serious postoperative complications. The arthroscopic Latarjet procedure has not yet been widely applied, and a clear understanding of the anatomical structure and the precise methods is required prior to operation performance. Satisfactory clinical outcomes can be achieved by thorough preoperative planning and proper implant fixation methods.

• The Journal of Korean Academy of Prosthodontics
• /
• v.36 no.4
• /
• pp.566-580
• /
• 1998

Implant-supported overdenture is known as a useful appliance, instead of using the conventional complete denture, for better retention and stability. In this study 4 types of materials such as, gold bar/plastic clip(group AuP), gold bar/metal clip(group AuM), palladium bar/plastic clip(group PdP), and palladium bar/metal clip (group PdM) were used to evaluate the retention forces according the type of clips and alloys used for bar fabrication, in the Hader bar system. Repeated insertions and removals of overdenture were conducted in each group. and the retention forces were measured and compared the data of each group according to the number of insertion and removal. The obtained results were as follows, 1. In the comparison of retention forces according to type of bar-clip, retention was increased in the order of group AuM, PdM, PdP AuP. and the retention force of group AuM was significantly increased compared with those of others (p<0.05). 2. In the comparison of retention forces according to the number of insertion, only group PdP showed significant decrease in retention(p<0.05). 3. In the comparison of retention forces according to the type of bar and clip. there was no significant difference in the type of bar, but the retention of plastic clip was significantly higher than that of metal clip when Au bar was used(p<0.05). 4. In the observation of the bar surface, group AuM using Au bar and metal clip showed the most scratches among bar groups.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.36 no.11
• /
• pp.1111-1117
• /
• 2012

Implants for rhinoplasty should ideally be biocompatible and possess long-term stability after implantation. Silicone implants are most widely used for rhinoplasty. However, these implants suffer from problems related to high extrusion and infection rates. To minimize these complications, we propose a novel augmentation rhinoplasty technique using tissue engineering. To demonstrate its feasibility, a nasal-implant-shaped scaffold was designed using commercialized CAD software and fabricated using a Multi-head Deposition System, which is a solid freeform fabrication system that dispenses material. In vitro cell proliferation and chondrogenic differentiation tests were carried out using nasal septal chondrocytes.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.29 no.4
• /
• pp.333-339
• /
• 2007

Adequate bone quantity is one of the important factor to obtain osseointegration after implantation. Guided bone regeneration (GBR) has widely used in implantation for reconstruction of bony defects. Since introducing this procedure, there are many studies about survival rate of implants, changing in surrounding bone volume after function. The purpose of this study was to evaluate the amount of resorption according to placement timing and survival rate after function. The subjects were patients who had been operated with GBR from Jun 2003 to Jun 2004 in Seoul National University Bundang Hospital. They were divided into simultaneous and delayed placement group. The follow up had been performed at the time of just after GBR, 1, 3, 6, 12, 24-month later and standard periapical radiographs were taken to estimate the bone level at the time. The total average of bone level change in radiographs was 1.94mm(${\pm}0.25$), and 1.92mm(${\pm}0.72$) in simultaneous installation, 2.03mm(${\pm}0.25$) in delayed installation. In this report, the survival rates were 92.2% in simulataneous group and 92.3% in delayed group. Insufficient primary stability, early contamination of wound, overloading, poor oral hygiene, and infection were thought to be associated factors in the failed cases.

• The korean journal of orthodontics
• /
• v.48 no.5
• /
• pp.283-291
• /
• 2018

Objective: This study was conducted to perform histomorphometric evaluations of the bone surrounding orthodontic miniscrews according to their proximity to the adjacent tooth roots in the posterior mandible of beagle dogs. Methods: Four male beagle dogs were used for this study. Six orthodontic miniscrews were placed in the interradicular spaces in the posterior mandible of each dog (n = 24). The implanted miniscrews were classified into no loading, immediate loading, and delayed loading groups according to the loading time. At 6 weeks after screw placement, the animals were sacrificed, and tissue blocks including the miniscrews were harvested for histological examinations. After analysis of the histological sections, the miniscrews were categorized into three additional groups according to the root proximity: high root proximity, low root proximity, and safe distance groups. Differences in the bone-implant contact (BIC, %) among the root proximity groups and loading time groups were determined using statistical analyses. Results: No BIC was observed within the bundle bone invaded by the miniscrew threads. Narrowing of the periodontal ligament space was observed in cases where the miniscrew threads touched the bundle bone. BIC (%) was significantly lower in the high root proximity group than in the low root proximity and safe distance groups. However, BIC (%) showed no significant differences among the loading time groups. Conclusions: Regardless of the loading time, the stability of an orthodontic miniscrew is decreased if it is in contact with the bundle bone as well as the adjacent tooth root.

• The Journal of the Korean dental association
• /
• v.53 no.11
• /
• pp.804-816
• /
• 2015

PURPOSE: The aim of this study was to evaluate the influence of the oxide layer removal process in the Co-Cr-Mo (CCM) abutment after casting procedure on the prosthesis settlement and screw stability. MATERIALS AND METHODS: CCM abutments of four different interface conditions (CCM-M; machined, CCM-O; oxide layer formed, CCM-B; blasted, CCM-P; polished after blasted) and gold abutment (Gold-C; Cast with type III Gold alloy) were used. The initial settling values of abutments were evaluated according to the difference of implant-abutment length when the tightening torques were applied at 5 Ncm and 30 Ncm, and the settling values of abutments caused by loading were evaluated according to the difference of implant-abutment length before and after loading with 250 N, 100000 cycle. The loss ratios of removal torque for abutment screws were evaluated according to the difference in value of removal torques under 30 Ncm tightening torque applied before and after cyclic loading. RESULTS: The CCM-P and CCM-B group showed a higher initial settling value compared with the Gold-C group (P<.05), while the Gold-C group showed the highest settling values caused by loading (P<.05) and no significant differences were observed for between CCM groups (P>.05). The loss ratio of removal torque values for the CCM-B, CCM-P groups did not differ significantly from that of the Gold-C group (P>.05). CONCLUSION: Even though the oxide layer was removed by different methods, CCM abutment with internal conical connection structure showed lower abutment settling and similar screw loosening after cyclic loading compared with gold abutment.

• The Journal of Advanced Prosthodontics
• /
• v.7 no.5
• /
• pp.375-379
• /
• 2015

PURPOSE. The purpose of this study was to evaluate the influence of tightening technique and the screw coating on the loosening torque of screws used for Universal Abutment fixation after cyclic loading. MATERIALS AND METHODS. Forty implants (Titamax Ti Cortical, HE, Neodent) (n=10) were submerged in acrylic resin and four tightening techniques for Universal Abutment fixation were evaluated: A - torque with 32 Ncm (control); B - torque with 32 Ncm holding the torque meter for 20 seconds; C - torque with 32 Ncm and retorque after 10 minutes; D - torque (32 Ncm) holding the torque meter for 20 seconds and retorque after 10 minutes as initially. Samples were divided into subgroups according to the screw used: conventional titanium screw or diamond like carbon-coated (DLC) screw. Metallic crowns were fabricated for each abutment. Samples were submitted to cyclic loading at $10^6$ cycles and 130 N of force. Data were analyzed by two-way ANOVA and Tukey's test (5%). RESULTS. The tightening technique did not show significant influence on the loosening torque of screws (P=.509). Conventional titanium screws showed significant higher loosening torque values than DLC (P=.000). CONCLUSION. The use of conventional titanium screw is more important than the tightening techniques employed in this study to provide long-term stability to Universal Abutment screws.

• Journal of Korean Dental Science
• /
• v.10 no.1
• /
• pp.35-44
• /
• 2017

In case of loss of many teeth due to dental caries or periodontal disease, improvement of masticatory function and aesthetics can be obtained through implant treatment. However, if the patient does not have a normal intercondylar relationship, it is difficult to achieve an ideal occlusal relationship with only prosthetic treatment. In particular, oral reconstruction with orthodontic treatment or orthognathic surgery is necessary for patients with mandibular prognathism. However, if the posterior occlusion collapses due to severe caries or periodontal disease, orthognathic surgery may be difficult. The occlusal vertical stop is very important for the stability of the mandibular position during occlusal reconstruction through orthognathic surgery. The patient in this case had posterior occlusion collapsed due to the caries of a large number of posterior teeth, and showed mandibular prognathism and long face. We planned a full arch restoration with orthognathic surgery and extracted the hopeless teeth. To secure the vertical stop required for orthognathic surgery, the implant was placed before surgery. After the orthognathic surgery and the final prosthesis application, the results were satisfactory for the improvement of the aesthetics and the restoration of the masticatory function.

• Journal of Korean Neurosurgical Society
• /
• v.30 no.10
• /
• pp.1170-1176
• /
• 2001

Objective : The purpose of the study was to evaluate the clinical and radiological results after discectomy and Lubboc bone graft in the surgical management of the cervical diseases with a new titanium interbody implant and integrated screw fixation(PCB) by anterior approach. Methods : The authors retrospectively analyzed 28 cases of anterior cervical fusion with PCB system and Lubboc bone(xeno graft) from september 1998 to december 2000. Twenty-eight patients with cervical diseases underwent decompression cervical lesion and followed from 5 to 27 months with a mean follow-up of 14 months. There patients were evaluated with clinically and radiologically at immediate postoperative period and at 3, 6, 9, and 12 months. Result : The authors investigated the pre- and postoperative intervertebral disc space, clinical outcomes, radiography fusion rate, and Cobb angle in the fixed segments by anterior approach. The lordotic angles and height of disc space were increased after the operation. The clinical outcome of patients follow-up was good or excellent result based on Odom's criteria with improvement of clinical symptom in about 92.9% of the cervical diseases. Two patients showed loosening of the lower and upper cervical screw of PCB instruments, and two patients showed swallowing difficulty and wound infection Conclusion : The PCB system is a new implant for anterior cervical interbody fusion in the degenerative cervical disease and disc herniations. It provides immediate stability and segment distraction. The results of this study indicate that the PCB system is safe, easy handling of hardware, less complications, high fusion rate, and has provide the keeping the intervertebral disc space height and lordotic angles.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.43 no.4
• /
• pp.276-281
• /
• 2017

This case series study demonstrates the possibility of successful implant rehabilitation without bone augmentation in the atrophic posterior maxilla with cystic lesion in the sinus. Sinus lift without bone graft using the lateral approach was performed. In one patient, the cyst was aspirated and simultaneous implantation under local anesthesia was performed, whereas the other cyst was removed under general anesthesia, and the sinus membrane was elevated in a second process, followed by implantation. In both cases, tapered 11.5-mm-long implants were utilized. With all of the implants, good stability and appropriate bone height were achieved. The mean bone level gain was 5.73 mm; adequate bone augmentation around the implants was shown, the sinus floor was moved apically, and the cyst was no longer radiologically detected. Completion of all of the treatments required an average of 12.5 months. The present study showed that sufficient bone formation and stable implantation in a maxilla of insufficient bone volume are possible through sinus lift without bone materials. The results serve to demonstrate, moreover, that surgical treatment of mucous retention cyst can facilitate rehabilitation. These techniques can reduce the risk of complications related to bone grafts, save money, and successfully treat antral cyst.