• Korean Journal of Computational Design and Engineering
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• v.20 no.4
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• pp.348-356
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• 2015

It is important to devise methods for assisting dentists to consistently determine implant positions and directions and to accurately perform drilling tasks during dental implant surgery. In this paper, we propose a novel approach to tooth implant placement planning which deals with the determination of the positions and directions of multiple implant fixtures for a set of missing mandibular teeth and suggests the selection of the sizes and types of the implant fixtures. We combine Korean standard data in the sizes and positions of human teeth with the patient specific 3D models of mandibular jawbones, nerve curves, and neighboring teeth around the missing teeth in order to determine the positions and directions of the implant fixtures for the missing teeth. Using the geometric and spatial information of the jawbones, the teeth and the implant fixtures, we can construct the 3D models of surgical guide stents which are crucial to perform drilling tasks with ease and accuracy. Adopted in 3D simulation of dental implant placement, the approach can provide surgeon students with good educational contents. We also expect that, with further work, the approach can be used as a useful tool to plan for dental implant surgery.

• Journal of Periodontal and Implant Science
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• v.51 no.4
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• pp.285-295
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• 2021

Purpose: The aims of the present study were 1) to quantitatively evaluate the extent of sinus pneumatization and 2) to determine the factors affecting sinus pneumatization. Methods: Based on implant treatment records, a list of patients who underwent implant placement on the posterior maxilla was obtained. Among them, patients with pre-extraction and post-extraction (before implant placement) panoramic radiographs were selected. After excluding radiographs with low resolution and image distortion, the radiographs before and after extraction were superimposed using computer software. Subsequently, the extent of sinus pneumatization (the vertical change of the sinus floor) was measured. Simple and multiple mixed models were used to determine the factors affecting sinus pneumatization. Results: A total of 145 patients were eligible for the present investigation. The average extent of sinus pneumatization was 1.56±3.93 mm at 176 tooth sites. Male sex, single tooth extraction, extraction of an endodontically compromised tooth, a class I root-sinus relationship, and sinus membrane thickening >10 mm favored pneumatization, but without statistical significance. The maxillary second molar presented the greatest pneumatization (2.25±4.39 mm) compared with other tooth types. This finding was confirmed in the multiple mixed model, which demonstrated a statistically significant impact of the extraction of a second molar compared with the extraction of a first premolar. Conclusions: Maxillary sinus pneumatization was 1.56±3.93 mm on average. The extraction of a second molar led to the greatest extent of pneumatization, which should be considered in the treatment plan for this tooth site.

• Journal of Dental Anesthesia and Pain Medicine
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• v.19 no.4
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• pp.239-244
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• 2019

The effectiveness of dental implants in patients with disability, who are non-compliant during treatment, is controversial because of their poor oral health. Thus, oral health-care and management in such patients is concerning. Moreover, limited information is available on prognosis after implant placement. Herein, we describe a patient with schizophrenia who underwent dental implantation under multiple inductions of general anesthesia (5 times) and required conservative treatment and tooth extraction for multiple dental caries and retained roots because of inadequate oral health-care. Postoperatively, fracture of the prosthodontics and progression of dental caries were observed, and with 3 additional inductions of general anesthesia, conservative treatment, implant surgery, and prosthesis implantation were conducted. Postoperative 12-month follow-up since the last prosthesis implantation showed successful results. For patients with schizophrenia, multiple implantation can reduce horizontal bone loss and achieve aesthetic results compared to treatment with removable prosthodontics and could serve as an alternative treatment modality.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.1
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• pp.14-20
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• 2016

Purpose: The aim of this study was to know whether there is significant difference of peri-implant bone density according to the state of antagonist region. Materials and methods: 51 patients who had implant operation in Daejeon Dental Hospital of Wonkwang University participated in this study and total of 51 implants were analyzed. Implants were classified depending on opposing antagonist region, gender, age and location of jaw. The opposing antagonist region was divided into four groups; natural tooth, implant, pontic and edentulous region. Fractal analysis was performed using two periapical radiographs; one after implant placement and the other after 10 weeks following prosthetic restoration. The analysis was done by Image J. The data was statistically analyzed using one-way ANOVA and Tukey multiple comparison test. Results: The mean value of fractal difference was $0.009{\pm}0.048$ with opposing natural tooth, $0.026{\pm}0.080$ with opposing implant, $0.025{\pm}0.068$ with opposing pontic and $0.093{\pm}0.171$ with opposing edentulous area. There was a statistically significant difference in fractal value between opposing implant and opposing edentulous state. And there was no statistically significant difference according to age, gender and location of jaw. Conclusion: There was no statistically significant difference between 3 groups except opposing edentulous region and there was a statistically significant difference between opposing implant and edentulous region. And there was no statistically significant difference according to age, gender and location of jaw.