• 대한의용생체공학회:의공학회지
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• 제17권1호
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• pp.61-70
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• 1996

In cementless total hip arthroplasty(THA), an initial stability of the femoral component is mandatory to achieve bony inyowth and secondary long term fixation. Primary stability of the femoral component can be obtained by minimizing the magnitude of relative micromotions at bone stem interface. An accurate evaluation of interf'ace micromotion and stress/strain fields in the bone-implant system may be relevant for better understanding of clinical situations and improving THA design. Recently finite element method(FEM) was introduced in'orthopaedic research field due to its unique capacity to evaluate stress in structure of complex shape, loading and material behavior. The authors developed the 3-dimensional finite element model of proximal femur with $Multilock^{TM}$ stem of 1179 blick elements to analyse the micromotions and mechanical behaviors at the bone-stem inteface in early post-operative period for the load simulating single leg stance. The results indicates that the values of relative motion for this well fit stem were $150{\mu}m$ in maximum $82{\mu}m$ in minimum and the largest relative motion was developed in medial region of Proximal femur and in anterior-posterior direction. The motion in the proximal bone was much greater than in the distal bone and the stress pattern showed high stress concentration on the cortex near the tip of the stem. These findings indicate that the loading on the hip joint in the early postoperative situation before achieving bony ingrowth could produce large micromotion of $150{\mu}m$ and clinicaly non-cemented THA patient should not be allowed weight bearing strictly early in the postoperative period.

• Journal of Dental Anesthesia and Pain Medicine
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• 제16권2호
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• pp.123-129
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• 2016

Background: The objective of the present study was to examine the status of patients who had received dental treatment under intravenous (IV) sedation at Chungnam Dental Clinic for the Disabled in Korea from its inception to the present time, and to review the analysis results. Methods: Retrospective analysis was performed on 305 cases of patients who had received dental treatments under IV sedation between January 2011 and May 2016. The analysis examined the patient's sex, age, primary reason for IV sedation, duration of anesthesia and dental treatment, type of dental treatment performed, number of clinical departments involved in the dental treatment and level of multidisciplinary cooperation, and annual trends. Results: Most dental treatments using intravenous sedation were performed on medically disabled patients or dentally disabled patients with an extreme gag reflex or dental phobia. The mean duration of IV sedation was 72.5 min, while the mean duration of treatment was 58.0 min. The types of dental treatments included surgical treatment (n = 209), periodontal treatment (n = 28), prosthodontic treatment (n = 28), restorative treatment (n = 23), implant surgery (n = 22), endodontic treatment (n = 9), reduction of temporomandibular joint dislocation (n = 1), and treatment of traumatic injuries (n = 1), with treatments mostly performed on adult patients. Conclusions: With increasing demand for minimally painful treatment, cases using IV sedation are on an upward trend and are expected to continue to increase.

• Journal of Periodontal and Implant Science
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• 제40권2호
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• pp.61-68
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• 2010

Purpose: The present study was performed to clarify the relationship between periodontal disease severity and selected immunological parameters consisting of serum IgG titer against periodontopathogenic bacteria, the expression of the helper T-cell cytokine by gingival mononuclear cells, and patients' immunoreactivity to cross-reactive heat shock protein (HSP) epitope peptide from P. gingivalis HSP60. Methods: Twenty-five patients with moderate periodontitis had their gingival connective tissue harvested of gingival mononuclear cells during an open flap debridement procedure and peripheral blood was drawn by venipuncture to collect serum. The mean level of interproximal alveolar bone was calculated to be used as an index for periodontal disease severity for a given patient. Each of selected immunologic parameters was subject to statistical management to seek their correlations with the severity of periodontal disease. Results: A significant correlation could not be identified between serum IgG titers against specific bacteria (Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans, and Streptococcus mutans) and the severity of periodontal disease. Expression of interleukin (IL)-10 by gingival mononuclear cells was statistically significant in the group of patients who had higher levels of alveolar bone height. However, a similar correlation could not be demonstrated in cases for IL-4 or interferon-$\gamma$. Patients' serum reactivity to cross-reactive epitope peptide showed a significant correlation with the amount of alveolar bone. Conclusions: It was concluded that expression of IL-10 by gingival mononuclear cells and patients' sero-reactivity to the cross-reactive HSP peptide of P. gingivalis HSP60 were significantly correlated with alveolar bone height.

• Journal of Periodontal and Implant Science
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• 제44권3호
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• pp.147-155
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• 2014

Purpose: In the anterior maxilla, hard and soft tissue augmentations are sometimes required to meet esthetic and functional demands. In such cases, primary soft tissue closure after bone grafting procedures is indispensable for a successful outcome. This report describes a simple method for soft tissue coverage of a guided bone regeneration (GBR) site using the double-rotated palatal subepithelial connective tissue graft (RPSCTG) technique for a maxillary anterior defect. Methods: We present a 60-year-old man with a defect in the anterior maxilla requiring hard and soft tissue augmentations. The bone graft materials were filled above the alveolar defect and a titanium-reinforced nonresorbable membrane was placed to cover the graft materials. We used the RPSCTG technique to achieve primary soft tissue closure over the graft materials and the barrier membrane. Additional soft tissue augmentation using a contralateral RPSCTG and membrane removal were simultaneously performed 7 weeks after the stage 1 surgery to establish more abundant soft tissue architecture. Results: Flap necrosis occurred after the stage 1 surgery. Signs of infection or suppuration were not observed in the donor or recipient sites after the stage 2 surgery. These procedures enhanced the alveolar ridge volume, increased the amount of keratinized tissue, and improved the esthetic profile for restorative treatment. Conclusions: The use of RPSCTG could assist the soft tissue closure of the GBR sites because it provides sufficient soft tissue thickness, an ample vascular supply, protection of anatomical structures, and patient comfort. The treatment outcome was acceptable, despite membrane exposure, and the RPSCTG allowed for vitalization and harmonization with the recipient tissue.

• Journal of Periodontal and Implant Science
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• 제44권3호
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• pp.134-140
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• 2014

Purpose: Triphala is a combination of three medicinal plants, extensively used in Ayurveda since ancient times. Triphala mouthwash is used in the treatment of periodontal diseases because of its antimicrobial and antioxidant properties. The aim of this study is to compare the efficacy of triphala mouthwash with 0.2% chlorhexidine in hospitalized periodontal disease patients. Methods: In this double-blind, randomized, multicenter clinical trial, 120 patients were equally divided into three groups. Patients in group A were advised to rinse their mouths with 10 mL of distilled water, group B with 0.2% chlorhexidine, and group C with triphala mouthwash for 1 minute twice daily for two weeks. The plaque index (PI) and the gingival index (GI) were recorded on the first and the fifteenth day. Results: There was no significant difference when the efficacy of triphala was compared with 0.2% chlorhexidine in hospitalized patients with periodontal disease. However, a statistically significant difference was observed in PI and GI when both group B and group C were compared with group A and also within groups B and C, after 15 days (P<0.05). Conclusions: The triphala mouthwash (herbal) is an effective antiplaque agent like 0.2% chlorhexidine. It is significantly useful in reducing plaque accumulation and gingival inflammation, thereby controlling periodontal diseases in every patient. It is also cost effective, easily available, and well tolerable with no reported side effects.

• Journal of Periodontal and Implant Science
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• 제38권2호
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• pp.225-230
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• 2008

Purpose: Many clinical studies have reported that higher success rates are achieved with teeth that have immature roots than other autotransplanted teeth that have more immature root. However, based on date published recently, the success rate of autotransplantation of teeth with complete root formation was higher. The purpose of this study was to examine the long term(2 to 6 years follow-up) success rate of autotransplantation of third molar with complete root formation and to discuss some conditions and prerequisites for success. Materials and Methods: 26 sites of 24 patients aged 26 to 55 (mean age 40.8) were autotransplanted with third molars with complete root formation. These cases were followed for 2 to 6 years after surgery. The success criteria included (1) no discomfort during functioning (2) absence of progressive root resorption and alveolar bone resorption. Result: Of 26 teeth 5 teeth were failed, therefore success rate is 81%(21/26 teeth). The results suggested that higher success rate is acquired from (1) extraction socket due to dental caries (2) mandibular recipient site (3) patient younger than 40 years old. Autotransplantation of third molar to replace molars with advanced periodontal disease also showed considerably high success rate(84%). Conclusion: With appropriate case selection, autotransplantation of third molar with complete root formation remains a viable alternative for replacing a missing molar tooth.

• Journal of Periodontal and Implant Science
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• 제48권1호
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• pp.3-11
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• 2018

Purpose: This study utilized a strong quasi-experimental design to test the hypothesis that the implementation of a policy to expand dental care services resulted in an increase in the usage of dental outpatient services. Methods: A total of 45,650,000 subjects with diagnoses of gingivitis or advanced periodontitis who received dental scaling were selected and examined, utilizing National Health Insurance claims data from July 2010 through November 2015. We performed a segmented regression analysis of the interrupted time-series to analyze the time-series trend in dental costs before and after the policy implementation, and assessed immediate changes in dental costs. Results: After the policy change was implemented, a statistically significant 18% increase occurred in the observed total dental cost per patient, after adjustment for age, sex, and residence area. In addition, the dental costs of outpatient gingivitis treatment increased immediately by almost 47%, compared with a 15% increase in treatment costs for advanced periodontitis outpatients. This policy effect appears to be sustainable. Conclusions: The introduction of the new policy positively impacted the immediate and long-term outpatient utilization of dental scaling treatment in South Korea. While the policy was intended to entice patients to prevent periodontal disease, thus benefiting the insurance system, our results showed that the policy also increased treatment accessibility for potential periodontal disease patients and may improve long-term periodontal health in the South Korean population.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제18권1호
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• pp.17-25
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• 1996

There are many reports of the surgical management for the craniofacial abnormalities arising from the irradiation of the head and face for treatment of childhood cancers. Since the mordern combined-modality theraphy for childhood cancers began in the late 1960s and the early 1970s, recent reports have described the occular, dental and maxillo-facial abnormalities after irradiation in long-term survivors of cancers of the head and face. The resultant deformities may be known to be difficult to reconstruct with surgical techniques. This paper describes the late reconstructive surgery for the unilateral orbital and malar hypoplasia after eyeball enucleation and irradiation during childhood to correct the facial asymmetry and expand the contracted orbital socket into the functional dimension for the retaining eyeball prosthesis with spherical implant. We reports the satisfactory preliminary results from the midfacial osteotomy through the supero-lateral orbital rim and malar bone and the antero-lateral repositioning with the autogenous bone grafting in 26 year-old female patient who will be planned to make the new eyeball prosthesis by the department of ophthalmology.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권6호
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• pp.343-350
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• 2019

Objectives: The aims of this study were to determine the effectiveness of local compression in patients presenting to the emergency room with intraoral bleeding and to identify when complex haemostatic measures may be required. Materials and Methods: Five hundred forty patients who had experienced intraoral haemorrhage were retrospectively reviewed. The outcome variable was the haemostasis method used, i.e., simple (local compression with gauze) or complex (an alternative method after local compression has failed). Predictor variables were sex, age, American Society of Anesthesiologists (ASA) class, hepatic cirrhosis, bleeding disorder, use of antithrombotic agents, and site/cause of haemorrhage. Results: The mean patient age was 48.9±23.9 years, 53.5% were male, 42.8% were ASA class II or higher, and 23.7% were taking antithrombotic agents. Local compression was used most often (68.1%), followed by local haemostatic agents, sutures, systemic tranexamic acid or blood products, and electrocautery. The most common site of bleeding was the gingiva (91.7%), and the most common cause was tooth extraction (45.7%). Risk factors for needing a complex haemostasis method were use of antithrombotic agents (odds ratio 2.047, P=0.009) and minor oral surgery (excluding extraction and implant procedures; odds ratio 6.081, P=0.001). Conclusion: A haemostasis method other than local compression may be needed in patients taking antithrombotic agents or having undergone minor oral surgery.

• Journal of Periodontal and Implant Science
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• 제36권2호
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• pp.567-577
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• 2006

Background Several bone grafting materials have been used in sinus augmentation procedures. Macroporous Biphasic Calcium Phosphate($MBCP^{TM}$) consists of the mixture of 60% HA and 40% ${\beta}-TCP$. Therefore, it can provide good scaffold for the new bone to grow owing to HA, in the other hand, it can have bioactivity for bone remodeling owing to ${\beta}-TCP$. The purpose of this study was to evaluate bone formation following maxillary sinus augmentation using $MBCP^{TM}$ by means of histologic analysis. Material and Method $MBCP^{TM}$ was placed as a primary bone substitute for maxillary sinus augmentation. Three patients were selected after evalaution of their medical dental examination. $MBCP^{TM}$ only, $MBCP^{TM}$ combined with Irradicated cancellous bone and $MBCP^{TM}$ combined with autogenous bone were used for each patient. After about eight months, bone biopsies were harvested for histologic evaluation and fixtures installed. Results Eight months after surgery we observed new vital bone surrounding $MBCP^{TM}$ particle and the amount of new bone was about 30% even though there were discrepancies between specimens. This case report documents that $MBCP^{TM}$ when used as a grafting material for sinus floor augmentation whether combined other bone graft material or not, may lead to the predictable results for dental implants on posterior maxillary area with insufficient vertical height for fixture installation.