• 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).

• Journal of Periodontal and Implant Science
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• v.54 no.2
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• pp.122-135
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• 2024

Purpose: This retrospective study aimed to assess the long-term cumulative survival rate of titanium, sandblasted, large-grit, acid-etched implants over a 10-year follow-up period and investigate the factors affecting the survival rate and change in marginal bone loss (MBL). Methods: The study included 400 patients who underwent dental implant placement at the Department of Periodontology of Seoul National University Dental Hospital (SNUDH) between 2005 and 2015. Panoramic radiographic images and dental records of patients were collected and examined using Kaplan-Meier analysis, Cox proportional hazards regression analysis, and multiple regression analysis to determine the survival rates and identify any factors related to implant failure and MBL. Results: A total of 782 implants were placed with a follow-up period ranging from 0 to 16 years (mean: 8.21±3.75 years). Overall, 25 implants were lost, resulting in a cumulative survival rate of 96.8%. Comparisons of the research variables regarding cumulative survival rate mostly yielded insignificant results. The mean mesial and distal MBLs were 1.85±2.31 mm and 1.59±2.03 mm, respectively. Factors influencing these values included age, diabetes mellitus (DM), jaw location, implant diameter, bone augmentation surgery, and prosthetic unit. Conclusions: This study found that the implant survival rates at SNUDH fell within the acceptable published criteria. The patients' sex, age, DM status, implant location, implant design, implant size, surgical type, bone augmentation, and prosthetic unit had no discernible influence on long-term implant survival. Sandblasted, large-grit, acid-etched implants might offer advantages in terms of implant longevity and consistent clinical outcomes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.1
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• pp.21-25
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• 2009

Objective: The purpose of this study is to determine the prevalence of sinus disease and abnormalities in patients scheduled for dental implant in maxillary posterior area using cone beam CT. Patients and Method: One hundred five maxillary sinuses in eighty-seven patients who underwent cone beam CT for dental implant in maxillary posterior area were included. Any patients who had previous history of sinus operations were not included. The sinus abnormalities were classified as follows ; normal (membrane thickness <2 mm), mucosal thickening (membrane thickness ${\geq}$ 2 mm and < 6 mm), partial opacification (membrane thickness > 6 mm but not full), full opacification and mucous retention cyst. The relationship between the remaining bone height, sinus symptoms and maxillary sinus abnormality was statistically surveyed. Results: Of 105 maxillary sinuses in 87 patients, 80 (76%) maxillary sinuses showed abnormalities ; 4 of 4 symptomatic patients and 76 of 101 asymptomatic patients. Mucosal thickening was the most common sinus abnormality. Only 3 (4%) of 80 maxillary sinus abnormalities were caused by the odontogenic origin. The prevalence of maxillary sinus abnormalities was higher in the symptomatic group than asymptomatic one (p<0.05). Conclusion: Maxillary sinus abnormalities were very common in the patients who were planning implantation in maxillary posterior areas. This result supports that thorough evaluation for maxillary sinus is recommended when implant treatment is planned for those areas.

• The Journal of the Korean dental association
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• v.54 no.12
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• pp.1024-1034
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• 2016

Purpose. The purpose of this study was to compare the type and frequency of prosthetic complications associated with attachment types for implant overdenture. Material and methods. In this retrospective study, 38 patients (mean age, 63.5 years) have been treated with implant overdentures from 2007 to 2014. Ten patients received a bar-clip attachment. Eleven patients had received a milled bar with Locator attachment. Seventeen patients had received a Locator attachment. The mean follow-up period was 36.9 months (range, 15-83 months). The type and frequency of prosthetic complications was recorded. The frequency was analyzed to determine the statistical difference among the 3 different attachments by using one-way ANOVA (${\alpha}=.05$) and Bonferroni post hoc method at a 5% level of significance. Results. The total number of prosthetic complications was higher in the bar-clip attachment (55 events) than in the milled bar with Locator attachment (39 events) and the Locator attachment (34 events). There were no statistically significant differences, and the most common prosthetic complication was the loss of retention. In the bar-clip attachment group, the average frequency of prosthetic complications was 3.0 events per prosthesis during the first year. In the milled bar with Locator attachment and Locator attachment groups, the average frequencies were 1.45 events and 2.35 events, respectively. Statistically significant differences were observed in the frequency of the complication. (p = .043) Conclusions. Compared to the bar-clip attachment, implant overdentures that use milled bars with the Locator attachment have a significantly lower incidence of prosthetic complications in the first year of follow-up after placement.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.2
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• pp.110-119
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• 2022

When restoration for partially edentulous patients, abutments are not always in favorable positions for making removable partial dentures. Because of these situations, patients are sometimes unsatisfied with the stability and support of their removable partial prostheses. In this regard, removable partial denture using a few implant surveyed crown prostheses can be a good alternative. It can be expected to increase stability and support of removable partial dentures by strategically placing a small number of implants and restoring with implant-supported surveyed crowns. In these cases, the patients who had unilateral residual teeth on mandible were treated with two implant surveyed crowns in the tactical place to have bilateral distribution. After definitive removable partial prosthesis, the patients showed satisfaction with the masticatory function and comfort of using removable dentures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.5
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• pp.260-266
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• 2019

Objectives: Dental implants shorter than 8 mm, called short dental implants (SDIs), have been considered to have a lower success rate than standard length implants. But recent studies have shown that SDIs have a comparable success rate, and implant diameter was more important for implant survival than implant length. Also, SDIs have many advantages, such as no need for sinus lifting or vertical bone grafting, which may limit use in medically compromised patients. Materials and Methods: In this study, 33 patients with 47 implants 7-mm long were examined over the last four years. All patients had special medical history and were categorized into 3 groups: systemic disorders, such as diabetes mellitus (controlled or uncontrolled), mental disability, and uncontrolled hypertension; oral cancer ablation with reconstruction, with or without radiotherapy; diverse osteomyelitis, such as osteoradionecrosis and bisphosphonate-related osteonecrosis of the jaw. Most of these patients have insufficient residual bone quality due to mandible atrophy or sinus pneumatization. Results: The implant diameters were 4.0 (n=38), 4.5 (n=8), and 5.0 mm (n=1). Among the 47 implants placed, 2 implants failed before the last followup. The survival rate of 7-mm SDIs was 95.74% from stage I surgery to the last follow-up. Survival rates did not differ according to implant diameter. The mean marginal bone loss (MBL) at 3 months, 1 and 2 years was significantly higher than at implant installation, and the MBL at 1 year was also significantly higher than at 3 months. MBL at 1 and 2 years did not differ significantly. Conclusion: Within the limitations of the present study, the results indicate that SDIs provide a reliable treatment, especially for medically compromised patients, to avoid sinus lifting or vertical bone grafting. Further, long-term follow-up is needed.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.6
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• pp.569-576
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• 2008

STATEMENT OF PROBLEM: While patient-centered outcomes are usually not reported, these may represent major aspects of the implant success for the patient. Use of a well-designed patient survey form can be an invaluable asset to the implant practitioners. PURPOSE: The objective of this study was to investigate patient satisfaction after implant therapy by means of a questionnaire. MATERIAL AND METHODS: South Korean patients (n = 100), who visited the dental examination center of Soon Chun Hyang university hospital, were asked to fill out the satisfaction questionnaire regarding aspects of cost, comfort, esthetics, chewing, gingival health, food impaction, phonetic aspect, screw loosening, and general satisfaction. Responses to statements were given on the Likert response scale. Four experimental groups of patients were distinguished with various location ($A_1,\;A_2,\;A_3$), year ($B_1,\;B_2,\;B_3$), number of implant replacements ($C_1,\;C_2,\;C_3$), and treatment cost ($D_1,\;D_2,\;D_3$). The reliability of the response scales was measured by calculation of its internal consistency, expressed as Cronbach's ${\alpha}$. The scales were distinguished by means of factor analysis method. Possible differences in scale scores among the groups were assessed by One-way ANOVA (${\alpha}$= 0.05). RESULTS: Patients responded to most of the statements with high satisfaction. But the mean scale score of statement about cost was low. After the verification of internal consistency and factor analysis, five components, e.g. general satisfaction, comfort, chewing efficiency, esthetics, and phonetic aspect were grouped together. These components could be explained with common meaning and the first factor was named as 'general satisfaction'. Differences in patient satisfaction on the scale with esthetics were present between patients who have been wearing the implant prosthesis less than three years and those more than seven years ($B_1<B_3$). CONCLUSION: The patients were generally satisfied with the outcome of implant treatment. But the patients' major complaint was high cost and while the statistically significant difference was not shown, the satisfaction scale about food impaction and esthetics was low. So the continuing efforts to make improvements about these problems are needed for the implant practitioners.

• Imaging Science in Dentistry
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• v.41 no.2
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• pp.59-62
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• 2011

Purpose : This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). Materials and Methods : This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. Results : The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. Conclusion : CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

• Journal of Korean society of Dental Hygiene
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• v.7 no.3
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• pp.285-299
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• 2007

The purpose of this study was to provide basic data of education program and consult for dental implant patient. The 210 of dental patients were selected at five dental clinic located in Jin-ju city. Data were collected by self-administrated questionnaire. A SPSS 10.10 for Windows was used for statistical analysis. The results of the study are summarized as follows: 1. The female responser was 56.2%, the rate of age was thirty years old 26.7%, education level was more than university and college 45.7%, job is company unit 15.2%, income was 100~200man won of 48.6%. 2. Recognition of dental implant was that incase of 'yes' is more than sixty years old 77.3%. 3. The information of implant was from neighborhood 29.0%, and when dental consult 24.3%. 4. The responsor who is everyone can take the dental implant operation is 39.5%, can not take is 32.9%. 5. The responsor who is everyone wants implant operation was 45.2%, 'do not' is 17.1%. 6. Using period of implant tooth is 'forever' 40.0%. In limited of twenty years' is 23.8%. 7. When everyone select to dental clinic was because of dentist medical technique is 64.3%, dental treatment cost is 15.9%. In conclusion, it is necessary for the dental implant patient to make dental consult and education program. So, try to study for make basic data with analysis recognition of dental implant patients.

• The Journal of Advanced Prosthodontics
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• v.7 no.5
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• pp.380-385
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• 2015

PURPOSE. The aim of this study was to determine the frequency of significant panoramic radiographic findings and eventual treatment requirements before conventional or implant supported prosthetic treatment in asymptomatic edentulous patients. MATERIALS AND METHODS. A total of 743 asymptomatic edentulous patients were retrospectively evaluated using a digital panoramic system. We analyzed the radiographic findings, including impacted teeth, retained root fragments, foreign bodies, severe atrophy of the posterior maxillary alveolar bone, mucous retention cysts, soft tissue calcifications and radiopaque-radiolucent conditions. RESULTS. Four-hundred-eighty-seven (65.6%) patients had no radiographic finding. A total of 331 radiographic findings were detected in 256 (34%) patients. In 52.9% (n=175) of these conditions, surgical treatment was required before application of implant-supported fixed prosthesis. However, before application of conventional removable prosthesis surgical treatment was required for 6% (n=20) of these conditions. CONCLUSION. The edentulous patients who will have implant placement for implant-supported fixed prosthesis can frequently require additional surgical procedures to eliminate pathological conditions.