• Journal of Korean Dental Science
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• v.12 no.1
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• pp.5-12
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• 2019

Purpose: To determine the benefits of autogenous tooth bone (ATB) graft in combination with platelet-rich plasma (PRP) in the rates of success and survival of dental implants placed simultaneously with maxillary sinus floor augmentation (MSFA). Materials and Methods: Patients who visited the Department of Oral and Maxillofacial Surgery at Ulsan University Hospital from 2012 to 2014 and underwent simultaneous placement of implants with MSFA using ATB plus PRP were included in the study. Success and survival rates of the implants were evaluated based on the parameters of age and sex of the patient, site, follow-up period, residual bone height before surgery, diameter, and length of implant, sinus mucosa impairment, and postoperative complications. Result: A total of 23 patients and 67 implants were included in this study. The average age of the patients was $53.78{\pm}10.00$ years. The average follow-up period after installation of the prosthesis was $53{\pm}5$ months. The success and survival rates of the implants after placement of prosthesis were 95.52% and 97.01%, respectively. Conclusion: Combination of ATB and PRP showed high overall success rate, and it can be concluded that this combination is a predictable bone graft procedure for MSFA.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.4
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• pp.306-312
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• 2010

Purpose: The purpose of this experiment was to evaluate the clinical effect of cultured autoglogous osteoblasts as a way to treat the defect of mandible in rabbits. Materials and Methods: Twelve rabbits were used to determine the rate of osteogenesis. The osteoblasts were obtained from the iliac crest of rabbits using aspiration. They were then cultured in Dulbecco's Modified Eagles's Medium (DMEM) with beta-glycerophosophatate, L-ascorbicacid, and dexamethasone to proliferate and differentiate osteoprogenitor cells. The expression of osteogenic markers were detected by reverse transcription-polymerase chain reaction (RT-PCR) and silver nitrate staining techniques. Five, 10-mm holes were placed in each rabbit mandible to simulate defective regions with the use of a low speed trephine bur. In the experimental group, the previously cited defects were grafted with both activated osteoblastic and autogenous bone. The control group, however, was only grafted with autogenous bone. Both groups were then analyzed at 2, 4, and 8-week intervals using bone histomorphometric analysis. Results: According to histomorphologic analysis, the rates of new bone formation at the 2, 4, and 8-week intervals were 36%, 51%, and 23% for the control group, respectively; 52%, 39%, and 28%, for the experimental group, respectively. The experimental group showed higher rates of new bone formation compared to the control group at both the 2-week and 8-week interval. Conclusion: Bone marrow-derived osteoblasts seems to be a promising bone graft material.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.5
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• pp.533-539
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• 2000

Recent development of dental implantology has taken an interest in the bone graft procedure. This is a review of literature, published from 1994 to November 1999. This study is provided by MEDLINE search. In this study, 718 patients received 829 graft with placing 2,677 endosseous implants. In mandible, nonvascularized or vascularized block bone grafts provided better results(success rate 95.2%) than particulate grafts(83.6%). But in maxilla, particulate grafts provided better results(93.7%, 86.2%) and more cases especially in sinus elevation. There were many cases using autogenous bone graft and revealed good results, but allogenic or alloplastic bone graft materials also were used by many surgeons.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.241-248
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• 2011

Purpose: The aim of this study was to present the clinical results of maxillary sinus augmentation implants and to evaluate the effects of various factors on the implant survival rate. Methods: In a total of 112 patients, 293 implants after sinus augmentation were performed. The total survival rate and the influence of the following factors on implant survival were evaluated; patient characteristics (sex, age, smoking, general disease), graft material, implant surface, implant installation stage, site of implant placement, length and width of implant, closure method for osseous window, residual alveolar bone height. Results: 1. Age ranged from 16 to 70 yr, with a mean of 45.7 yr. 2. Cumulative survival rate for the 293 implants with the maxillary sinus augmentation procedure was 94.9%. 3. Simultaneous implant installation was performed in 122 patients and delayed implant installation was performed in 117 implants. The average healing period after sinus elevation was 7.3 months for delayed implant installation and this procedure had a significantly higher survival rate. 4. There were no significant differences in sex, age, smoking, general disease, site of implant placement, length and width of implant, residual alveolar bone height and the survival rate. 5. RBM (Resorbable Blasting Media) implant surface and allograft groups had significantly lower survival rates. Conclusion: These data suggest that maxillary sinus augmentation may give more predictable results for autogenous bone grafts and delayed implant placement.

• Journal of Chest Surgery
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• v.21 no.2
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• pp.246-253
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• 1988

An in vitro model providing with a recirculating perfusion apparatus using an isolated canine heart and its autogenous blood, which was prepared for study of myocardial protection method. This apparatus was easily used by quick connect system and maintained well heart function for about 2 hours. The Langendorff perfusion was initiated for a 10 minute period by introducing perfusate at 37` into the aorta from aortic reservoir located 100 cm above the heart. The isolated perfused working canine heart model was a left heart preparation in which oxygenated perfusion medium [at 37K] entered the cannulated left atrium at a constant flow rate [900ml/ min] under 20 mmHg overflow system and was spontaneously ejected[no electrical pacing] via an cannula against a hydrostatic pressure of 80 cm H2O. During this working period, various indices of cardiac function were measured. The cardiac functions were stable for over 2 hours with perfusion of Krebs-Henseleit solution and autologous blood[1:1] mixture in volume and maintained heart rate ]]3-122/bpm peak systolic pressure 109-113 mmHg, cardiac output 900 ml / min and left atrial mean pressure 8-9 mmHg. In this model, the efficiency of myocardia] protection could be easily measured by means of functional, enzymatic, biochemical and ultrastructural assessment. And also, we believe this model to be a useful assessment screening model of recovery state after long duration of myocardial preservation of donor heart without difficult transplantation procedures.

• Journal of the Korea Concrete Institute
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• v.14 no.6
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• pp.813-822
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• 2002

The purpose of the present study is first to refine the mathematical material models for moisture and temperature distributions in early-age concrete and then to incorporate those models into finite element procedure. The three dimensional finite element program developed in the present study can determine the degree of hydration, temperature and moisture distribution in hardening concrete. It is assumed that temperature and humidity fields are fully uncoupled and only the degree of hydration is coupled with two state variables. Mathematical formulation of degree of hydration Is based on the combination of three rate functions of reaction. The effect of moisture condition as well as temperature on the rate of reaction is considered in the degree of hydration model. In moisture transfer, diffusion coefficient is strongly dependent on the moisture content in pore system. Many existing models describe this phenomenon according to the composition of mixture, especially water to cement ratio, but do not consider the age dependency. Microstructure is changing with the hydration and thus transport coefficients at early ages are significantly higher because the pore structure in the cement matrix is more open. The moisture capacity and sink are derived from age-dependent desorption isotherm. Prediction of a moisture sink due to the hydration process, i.e. self-desiccation, is related to autogenous shrinkage, which may cause early-age cracking in high strength and high performance concrete. The realistic models and finite element program developed in this study provide fairly good results on the temperature and moisture distribution for early-age concrete and correlate very well with actual test data.

• Journal of Periodontal and Implant Science
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• v.41 no.2
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• pp.86-91
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• 2011

Purpose: The aim of this study was to analyze the short-term predictability and reliability of Astra Tech implants according to the demographical distribution of patients and condition of implant sites and location of implants. Methods: Among patients treated with Astra Tech implant (Astra Tech AB) in the Department of Periodontology at the Dental Hospital of Yonsei University of College of Dentisry and K Dental Clinic from May 2004 to March 2009, 195 implants in 98 patients which had been restored more than 6 months ago were reviewed in this study. Following data were reviewed from patient charts and implants success rate was examined: 1) patient type and implant location, 2) bone status at the implant site, 3) diameter and length of the placed implants, 4) presence or absence of bone augmentation and types of the augmentation. Results: The results from this study are as follows: 1) most implants were placed in the molar area, especially 1st molar area of maxilla, 2) most implants were placed at $D_2$ and $D_3$ bone type, 3) most implants were placed in areas of B and C bone quantity, 4) autogenous and alloplastic bone graft and artificial membrane were used for placement of 74 implants. Conclusions: Short-term survival rate of Astra Tech implants was 100%.

• Journal of Korean Neurosurgical Society
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• v.30 no.12
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• pp.1388-1393
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• 2001

Objective : In the retrospective analyzing 19 consecutive patients with subaxial cervical spine(C3~T1) injury treated by posterior cervical fixation and fusion, clinical manifestation, radiologic finding, operative technique, and postoperative results following 6 months were analyzed. Materials and Methods : Most common fracture level was C4-5, mean age 41, and male to female ratio 13 : 6. The most common cause of injury was motor vehicle accident(17 cases). In 19 cervical procedures, interspinous triple wiring was done in 14 cases, lateral mass plating in 5 cases, and additional anterior fusion in 2 cases. Results : Twelve weeks after operation, all cases were reviewed by plain cervical radiogram. In 17 cases that treated by posterior fusion only, 14 cases(81%) had kyphotic angle change less than $5^{\circ}$, 2 cases(12%) $5-20^{\circ}$, and 1 case(6%) more than $20^{\circ}$. Overall fusion rate was 88%, and there was no significant difference of bone fusion rate between autogenous bone graft and allogenous bone graft. Conclusion : In the case of severe posterior column injury or displacement, posterior approach seems superior to anterior approach, but in the case of combined anterior column injury, anterior approach is considered necessary. In this study, posterior fixation and fusion might be acceptable procedure for subaxial cervical fracture and dislocation, owing to its high fusion rate, low kyphotic angulation and low operation related complication rate.

• Journal of Periodontal and Implant Science
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• v.38 no.sup2
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• pp.309-316
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• 2008

Purpose: The aim of this study was to determine the survival rates of implants placed in grafted maxillary sinuses and compare the results obtained with graft materials, implant surfaces and timing of implant placement. Materials and Methods: Between January 1996 and December 2005, 391 implants were placed in 161 patients who underwent sinus grafting treatment simultaneously or separately at Ewha Womans University Hospital. According to inclusion criteria, 272 implants were placed in 102 patients with 112 sinus grafts (30 females, 72 males), aged 26 to 88 years (mean age $49.0{\pm}9.7$). The follow-up period ranged from 12 to 134 months (mean F/U $47{\pm}32$). Survival rates were evaluated according to graft material, implant surface and timing of implant placement. The Kaplan-Meier procedure and the log rank (Mantel-Cox) test were used to estimate survival rates and test for equality of survival rates between different groups of patients. Results: Ten-year cumulative survival rate for implants placed in the grafted sinuses was 90.1%. The survival rates for autogenous bone, combination and bone substitutes were 94.6%, 85.9% and 100%, respectively (p > 0.05). According to implant surface, survival rates were 84.8% in machined group and 97.5% in rough group (p < 0.05). The survival rates were 92.9% in delayed group and 86.0% in simultaneous group (p > 0.05). Conclusion: Ten-year cumulative survival rate for implants placed in the grafted sinuses was 90.1%. Rough-surfaced implants have a higher survival rate than machined-surfaced implants when placed in grafted sinuses (p < 0.05).

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.376-381
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• 1999

A variety of materials and procedures such as sinus floor elevation, sinus-lift graft, inlay bone graft using Le Fort I osteotomy, and onlay graft have been used to create adequate bone volume in the maxillary sinus for placement of endosseous implants in the posterior atrophic maxilla. Because of the frequent lack of bone in the posterior maxilla, sinus lift procedure has become a commonly practiced treatment modality. The 138 endosseous implants of 36 patients with sinus augmentation procedures performed in Korea University Hospital from January 1991 to December 1998 were summarized and analysed. The result of this study were as follows: 1. Age ranged from 39 to 57, with a mean of 50.7. 2. The mean survival rate for 138 implants with maxillary sinus lift procedure was 80.4%. 3. There was no corelationship between the fixture length, width and the survival rate. 4. The result showed that the healing period for 8-12 months was necessary if the residual alveolar bone height was less than 5mm. 5. Autogenous iliac corticocancellous block graft showed the most favorable survival rate(95%).