• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.1
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• pp.72-78
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• 2016

This study examined the oral health-related quality of life of the elderly using the oral health index and dental prosthesis status, and explored methods to improve the oral health status. The data collected from 'The fifth Korean national health and nutrition examination survey 2010' were analyzed. The subjects were 2273 elderly people, aged 65 years or older, who had completed an oral examination, health questionnaires and nutrition examination. Statistical analysis was done using the SPSS 22.0 for Windows. Frequency analysis, multiple regression analysis and structural equation model were used for statistical analysis. The general characteristics, oral health index and dental prosthesis showed differences in the subjective oral health status associated with as age, ST, FS-T, T-Health, maxillary crown needs, maxillary denture needs, mandibular denture needs, chewing status associated with the income level, FS-T, maxillary crown needs, maxillary denture needs, mandibular denture needs, speaking status associated with the ST, T-Health, maxillary implant status, and maxillary denture needs. In conclusion, both the oral health index and dental prosthesis needs affect the oral health related quality of life of the elderly. Governments should implement a variety of oral health programs and dental prosthesis policies to improve the quality of life related oral health of the elderly.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.31 no.4
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• pp.330-333
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• 2009

Alveolar bone resorption after extraction impairs the necessary bone volume and complicates the case for implant surgery and aesthetic implant prosthesis. Immediate implant surgery after extraction decreases the number of surgical procedures and the duration of treatment, while allowing minimum alveolar bone resorption and preserving the residual bone volume. Although immediate implant holds many advantages such as preservation of hard and soft tissue around the extraction socket, greater implant survival rate and higher patient satisfaction, various complications and high failure rate are discouraging factors for the clinicians. In this case report, severe alveolar bone resorption with soft tissue changes were predicted after the extraction of prolonged retained deciduous incisors and impacted maxillary canines and thus decided on immediate implant procedure. Immediate implant surgery after extraction was carried out with minimal bone reduction and tapered wide-neck implant to establish initial stability. Simultaneous bone graft was done by filling the defect area with iliac cancellous bone with additional onlay-type bone graft and absorbable membrane on the labial bone for upper lip support. A stable and esthetic result was obtained with shortened treatment period.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.105-113
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• 2018

Purpose: The purpose of this study was to investigate the effects of the insertion depth of an immediately loaded implant on the stress distribution of the surrounding bone and the micromovement of the implant using the three-dimensional finite element analysis. Materials and methods: A total of five bone models were constructed such that the implant platform was positioned at the levels of 0.00 mm, 0.25 mm, 0.50 mm, 0.75 mm, and 1.00 mm depth from the crest of the cortical bone. A frictional coefficient of 0.3 and the insertion torque of 35 Ncm were simulated on the interface between the implant and surrounding bone. A static load of 178 N was applied to the provisional prosthesis with a vertical load in the axial direction and an oblique load at $30^{\circ}$ with respect to the central axis of the implant, then a finite element analysis was performed. Results: The implant insertion depth significantly affected the stress distribution on the surrounding bone. The largest micromovement value of the implant was $39.34{\mu}m$. The oblique load contributed significantly to the stress distribution and micromovement in comparison to the vertical load. Conclusion: Increasing the implant insertion depth was advantageous in dispersing the concentrated stress in the cortical bone and did not significantly affect the micromovement associated with early osseointegration failure.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.1
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• pp.119-126
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• 2022

Mini-implant has been reported as an alternative method to conventional diameter implants in the treatment of mandibular anterior region with narrow ridge. However, one-piece type mini-implant showed biological and technical complications, such as peri-implantitis by residual cement and prosthetic detachment. Recently, one-piece type mini-implant with additional retentive structure has been introduced to increase the retention and stability of the mini-implant. The mini-implant is based on spreading the upper retentive structure with a spreader and connected it with the inner surface of the zirconia prosthesis. In two cases, we tried to reduce these complications through the mini-implant on the narrow mandibular anterior region, and it was possible to reduce the overall treatment period through a digital system. In this case report, restoration using the digital mini-implant system showed improvement of patient satisfaction on the aspect of function and esthetic in the narrow mandibular anterior region.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.4
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• pp.412-419
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• 2022

For treatment of partially edentulous patients, a treatment using implant is widely used. Treatment method using implant are implant fixed prostheses and removable partial dentures, and for patients with severe bone resorption, removable implant overdenture with the effects of aesthetic and reducing cost can be used as treatment options. Specially, prosthesis with milled-bar and attachment has the effect of being splinted between implant fixtures, higher retention and stability than conventional removable partial denture. And it has the effect of improvement of aesthetic through lip support by denture base. In this case, the patient with severe alveolar bone resorption and partial edentulous maxilla and mandible was treated by implant-assisted removable partial denture using Milled-bar and ADD-TOC attachment. The esthetic was improved by removing the clasp because of effects of additional retention by using the attachment, and reducing palatal coverage of implant-assisted removable partial denture. The clinical results were satisfactory on the aspect of aesthetic and masticatory function.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.146-156
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• 2024

Implant assisted removable partial denture (IARPD) has been practiced in various forms for a long time, and among them, implant surveyed crown RPD is gaining predictability as well as being considered as a treatment option for patients with anatomical and financial disadvantages. The position of implant could be divided as posterior placement or anterior placement according to the purpose of the treatment and should be planned in consider to the alveolar ridge of patient, anticipated prognosis of remaining teeth, and opposing dentition. This case report describes a treatment for mandibular Kennedy class I partial edentulous patient with two implant-supported surveyed crown and implant assisted removable partial denture. Given the difficulty of posterior placement in this patient and the prognosis of the residual teeth, the plan was to place two implants in close proximity to the residual teeth, which were placed in the planned position, angle, and depth using guided surgery. The process of fabricating the fixed prosthesis was carried out in parallel with the maxillary edentulous tooth arrangement process to increase predictability, and when fabricating the localized tooth, the implant was designed in a form that allows the patient to perform functional movements by preventing excessive loading as the last supporting tooth, and was fabricated through a secondary impression process. Each treatment procedure was proceeded as planned, with aesthetically and functionally satisfactory results for both patient and operator.

• Clinics in Shoulder and Elbow
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• v.24 no.1
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• pp.42-52
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• 2021

Reverse shoulder arthroplasty is an ideal treatment for glenohumeral dysfunction due to cuff tear arthropathy. As the number of patients treated with reverse shoulder arthroplasty is increasing, the incidence of complications after this procedure also is increasing. The rate of complications in reverse shoulder arthroplasty was reported to be 15%-24%. Recently, the following complications have been reported in order of frequency: periprosthetic infection, dislocation, periprosthetic fracture, neurologic injury, scapular notching, acromion or scapular spine fracture, and aseptic loosening of prosthesis. However, the overall complication rate has varied across studies because of different prosthesis used, improvement of implant and surgical skills, and different definitions of complications. Some authors included complications that affect the clinical outcomes of the surgery, while others reported minor complications that do not affect the clinical outcomes such as minor reversible neurologic deficit or minimal scapular notching. This review article summarizes the processes related to diagnosis and treatment of complications after reverse shoulder arthroplasty with the aim of helping clinicians reduce complications and perform appropriate procedures if/when complications occur.

• Structural Engineering and Mechanics
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• v.88 no.6
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• pp.583-588
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• 2023

Total hip replacement is a crucial intervention for patients with fractured hips who face challenges in natural recovery. The design of durable prostheses requires a comprehensive understanding of the natural processes occurring in bone. This article focuses on static loading analysis, specifically during stumbling activity, aiming to enhance the longevity of prosthetic implants. Three distinct implants, Charnley, Osteal, and Thompson, were selected for a detailed study to determine the most appropriate model. The results revealed critical insights into the distribution of Von Mises stresses on the components of femoral arthroplasty, including the cement, implant, and cortical bone. Furthermore, the examination of shear stress within the cement emerged as a pivotal aspect for all three implants, playing a crucial role in evaluating the performance and durability of hip prostheses. The conclusions drawn from this study strongly suggest that the Thompson model stands out as the most suitable choice for hip joint implants.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.2
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• pp.108-118
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• 2010

Introduction: Maxillary posterior region, compared to the mandible or maxillary anterior region, has a thin cortical bone layer and is largely composed of cancellous bone, and therefore, it is often difficult to achieve primary stability. In such cases, sinus elevation with bone graft is necessary. Materials and Methods: In this research, 121 patients who had implant placement after bone graft were subjected to a follow-up study of 5 years from the moment of the initial surgery. The total survival rate, 5-year cumulative survival rate and the influence of the following factors on implant survival were evaluated; the condition of the patient (sex, age, general body condition), the site of implant placement, diameter and length of the implant, sinus elevation technique, closure method for osseous window, type of prosthesis and opposing teeth. Results: 1. The 5-year cumulative survival rate of total implants was 90.5%, there was no significant difference between sex, age, the site of implant placement, diameter and length of the implant, sinus elevation technique, and the type of opposing teeth. 2. Patients with diabetes mellitus < osteoporosis and smooth-surfaced machined group < hydroxyapatite (HA)-treated group and homogenous demineralized freeze dried allogenic bone (DFDB) bone graft only group had significantly lower survival rate. 3. With less than 4 mm of residual alveolar ridge height, lateral approach without closing the osseous window resulted in a significantly lower survival rate. 4. Restoration of a single implant showed a significantly lower survival rate, compared to cases where the superstructure was joined with several implants in the area. Conclusion: Patients with diabetes or osteoporosis need longer period of time for osseointegration compared to the normal, and the dentists must be prudent when choosing a surface treatment type and the bone graft material. Also, as the vertical dimension of the residual alveolar ridge can influence the result, staged implant placement should be considered when it seems difficult for the implant to gain primary stability from the residual bone with less than 4 mm of vertical dimension. It is recommended to obdurate the bone window and that the superstructure be connected with several impants in the peripheral area.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.4
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• pp.331-338
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• 2004

Stress transfer to the surrounding tissues is one of the factors involved in the design of dental implants. Unfortunately, insufficient data are available for stress transfer within the regenerated bone surrounding dental implants. The purpose of this study was to investigate the concentration of stresses within the regenerated bone surrounding the implant using three-dimensional finite element stress analysis method. Stress magnitude and contours within the regenerated bone were calculated. The $3.75{\times}10-mm$ implant (3i, USA) was used for this study and was assumed to be 100% osseointegrated, and was placed in mandibular bone and restored with a cast gold crown. Using ANSYS software revision 6.0, a program was written to generate a model simulating a cylindrical block section of the mandible 20 mm in height and 10 mm in diameter. The present study used a fine grid model incorporating elements between 165,148 and 253,604 and nodal points between 31,616 and 48,877. This study was simulated loads of 200N at the central fossa (A), at the outside point of the central fossa with resin filling into screw hole (B), and at the buccal cusp (C), in a vertical and $30^{\circ}$ lateral loading, respectively. The results were as follows; 1. In case the regenerated bone (bone quality type IV) was surrounded by bone quality type I and II, stresses were increased from loading point A to C in vertical loading. And stresses according to the depth of regenerated bone were distributed along the implant evenly in loading point A, concentrated on the top of the cylindrical collar loading point B and C in vertical loading. And, In case the regenerated bone (bone quality type IV) was surrounded by bone quality type III, stresses were increase from loading point A to C in vertical loading. And stresses according to the depth of regenerated bone were distributed along the implant evenly in loading point A, B and C in vertical loading. 2. In case the regenerated bone (bone quality type IV) was surrounded by bone quality type I and II, stresses were decreased from loading point A to C in lateral loading. Stresses according to the depth of regenerated bone were concentrated on the top of the cylindrical collar in loading point A and B, distributed along the implant evenly in loading point C in lateral loading. And, In case the regenerated bone (bone quality type IV) was surrounded by bone quality type III, stresses were decreased from loading point A to C in lateral loading. And stresses according to the depth of regenerated bone were distributed along the implant evenly in loading point A, B and C in lateral loading. In summary, these data indicate that both bone quality surrounding the regenerated bone adjacent to implant fixture and load direction applied on the prosthesis could influence concentration of stress within the regenerated bone surrounding the cylindrical type implant fixture.