• The Journal of Korean Academy of Prosthodontics
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• v.46 no.6
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• pp.634-638
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• 2008

PURPOSE: The application of computer-aided technology to implant dentistry has created new opportunities for treatment planning, surgery and prosthodontic treatment, but the correct selection and combination of available methods may be challenging in times. Hence, the purpose of this case report is to present a combination of several computer-aided tools as approaches to manage complicated implant case. MATERIAL AND METHODS: A 47 year-old female patient with severe dental anxiety, high expectations, financial restrictions and poor compliance presented for a fixed rehabilitation. A CT scan with a radiographic template obtained with software (SimPlant, Materialize, Leuven, Belgium) was used for treatment planning. The surgical plan was created and converted into a stereolithographic model of the maxilla with bone-supported surgical templates (SurgiGuide, Materialise, Leuven, Belgium), that allowed for the precise placement of 7 implants in a severely resorbed edentulous maxilla. After successful osseointegration, an accurate scan model served as the basis for the fabrication of a one-piece milled titanium framework using the Procera (Nobel Biocare, Gothenburg, Sweden) technology. The final rehabilitation of the edentulous maxilla was rendered in the form of a screw-retained maxillary metal-reinforced resin-based complete prosthesis. RESULTS: Despite challenging circumstances, 7 implants could be placed without bone augmentation in a severely resorbed maxilla using the SimPlant software for pre-implant analysis and the SurgiGuide-system as the surgical template. The patient was successfully restored with a fixed full arch restoration, utilizing the Procera system for the fabrication of a milled titanium framework.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.297-306
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• 1991

The purpose of this study is to improve the availabilities of radiographic technics as diagnostic methods to evaluate maxillary sinus in dental clinic. For the morphologic study of maxillary sinus, 20 dry maxillas were used and intraoral standard views, orthopantomograms, and skull P-A views were taken. For measuring the vertical image magnification rates, 5 sites in maxillary molar regions of 5 dry mandibles were selected radndomly and 25 wires of the determined sizes for selected portions were attached to the sites, after then, intraoral radiograms with bisecting technic and orthopantomograms were taken. The acquired results were as follows: 1. The anterior extension of the maxillary sinus on orthopantomogram was the distal side of the canine in 45.45% of subjects, the mesial side of the canine in 27.27%, the lateral incisor in 9.09%, the mesial side of the 1st premolar in 9.09%, and the mesial side of the 2nd pre-molar in 9.09%. 2. The positional relationship between the floor of maxillary sinus and the apex of alveolar socket revealed superimposed type in 58.3% of subjects, approached type in 33.3%, and separated type in 8.4%. 3. The morphology of inferior border of maxillary sinus was simple V or U shape in edentulous stage and V or wide U shape in alveolar socket stage. 4. The vertical image length on intraoral film taken by bisecting technic was magnified by 27.23% on the average and the length on orthopantomogram by 12.35%. 5. The inferior borders of maxillary sinus coinciding with each of the areas bearing the anterior and the posterior teeth on skull P-A view were determined.

• The Journal of Korean Academy of Prosthodontics
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• v.14 no.1
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• pp.66-71
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• 1976

The purpose of this investigation was to evaluate the mouth preparation and design of removable partial dentures. A total of 187cases for the prefabricated partial denture frameworks in both maxillary and mandibular semi-dentulous situations (66 cases and 203 cases) was selected from this study. The evaluations of mouth preparation and design observed here involved the classification of edentulous spaces, status of abutment splinting with location, design of direct retainer and structure of maxillary major connector according to the incidence of both dental arches, ages, sexes and segment of semidentulousness. The analyzed results were as follows: 1) The order of frequency rate in removable partial denture construction was Class II (50.27%), Class I (36. 90%), Class III (10.69%), and Class IV (2.14 %). 2) The distribution on design of maxillary removable partial denture prosthesis was 33.22% and 64.11% in mandibular removable partial denture prosthesis. 3) The age distribution of removable partial denture prosthesis was prominent after40 years (41.71%). 4) The design pattern of maxillary major connectors was in order of anteroposterior bar, single palatal bar, palatal strap, U-shape connector. 5) The design pattern of direct retainer was in order of Aker's clasp, I-bar clasp, backaction clasp, cuspid universal clasp. 6) The abutment for partial denture clasp splinted between premolar and premolar and its frequency rate revealed 53.44%. 7) It seemed that the location and design of the indirect retainer showed accepatble limit.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.2
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• pp.145-155
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• 2007

The advent of osseointegration and advances in biomaterials and techniques have contributed to increased application of dental implants in the restoration of maxillary partial edentulous patients. Often, in these patients, soft and hard tissue defects result from a variety of causes, such as infection, trauma, and tooth loss. These create an anatomically less favorable foundation for ideal implant placement. Reconstruction of the atrophic maxillary alveolar bone through a variety of regenerative surgical procedures has become predictable; it may be necessary prior to implant placement or simultaneously at the time of implant surgery to provide a restoration with a good long-term prognosis. Regenerative procedures are used for horizontal and vertical ridge augmentation. Many different techniques exist for effective bone augmentation. The approach is largely dependent on the extent of the defect and specific procedures to be performed for the implant reconstruction. It is most appropriate to use an evidenced-based approach when a treatment plan is being developed for bone augmentation cases. The cases presented in this article clinically demonstrate the efficacy of using a autogenous block graft, guided bone regeneration, ridge split, immediated implant placement technique on the atrophic maxillary area.

• The Journal of Korean Academy of Prosthodontics
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• v.53 no.4
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• pp.310-317
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• 2015

Purpose: The purpose of this study was to evaluate the validity of reference points for edentulous patient by examining the correlation of teeth and face, and intraoral anatomic landmarks. Materials and methods: We examined a facial outline, length, bizygomatic width, nasion - gnathion length, glabella - nasion distance in 270 men and 280 women satisfied with inclusion criteria from Seoul National School of Dentistry. The shape of maxillary central incisor, mesiodistal crown width and length of maxillary 6 incisors, distance from incisive papilla to labial surface of maxillary central incisor, and perpendicular distance from incisive papilla to intercanine line were measured in the stone model. We analyzed the ratio and relevant relation statistically. Results: The probability on having the same shape of face and the relative same shape maxillary incisor was 55.56% and 46.43% for men and women. The facial length proved to be a more valuable measurement in women in the tooth selection. The ratio of bizygomatic width to mesiodistal width of maxillary central incisor, and the ratio of bizygomatic width to width of maxillary 6 incisors were 16.8 : 1 and 3.0 : 1 and were positively correlated with each other. The distance of the canines from the maxillary incisal papilla was $1.33{\pm}1.28mm$. The distance between the center of the incisal papilla and the labial surface of their maxillary central incisor was $9.23{\pm}1.20mm$. Conclusion: It was showed that anatomical reference points in tooth selection and arrangement for edentulous patient are useful and have validity in our limited study.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.1
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• pp.34-39
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• 2021

Objectives: The purpose of the study was to assess the occurrence, location, and dimensions of the intraosseous vascular canal in the lateral wall of the maxillary antrum using cone-beam computed tomography (CBCT). Materials and Methods: In this retrospective study, we examined 400 CBCT scans from our archive of patients who had earlier reported to a dental teaching hospital in the United Arab Emirates. The prevalence, location, and dimensions of the lateral antral intraosseous canal (LAIC) in the maxillary antrum were evaluated by 2 examiners using standardised methods. A third examiner was consulted in cases of disagreement. Results: The prevalence of LAIC was 62.3% (249 maxillary antra) among the study population. The mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC in the posterior maxillary region was 19.83±3.12 mm. There was a significant difference (P=0.05) between the maxillary molar and premolar regions in mean distance from the most inferior point of the alveolar bone and the inferior border of the LAIC. There was no statistically significant difference in mean distance between the most inferior point of the alveolar bone and the inferior border of the LAIC between dentulous and edentulous areas (P=0.1). The G3-intrasinusal type canal less than 1mm in diameter was the most common type of LAIC. Conclusion: This study established the approximate location of the LAIC in a United Arab Emirates cohort, which will assist the oral surgeon in selecting the appropriate site for sinus lift procedures with reduced risk of surgical hemorrhage.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.2
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• pp.128-135
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• 2014

Treatment options for partially edentulous patients are fixed partial denture, removable partial denture and implant supported fixed partial denture. In case of a patient with a few remaining teeth, removable partial denture and implant supported fixed prosthesis are available. For implant fixed prothesis, enough implant fixtures are required and the patient's general condition, local factors and economic status must be considered. When the condition of the abutments and the residual ridge is favorable and the prosthesis is well designed, removable partial denture can be an option. In removable partial denture, the bilateral support is important. If the teeth remain unilateral, harmful stress is put on the abutments by the fulcrum line. In this situation, strategic implantation and implant-retained or assisted removable partial denture is beneficial to the retention and support of the denture. And this can be cost-effective, functional and esthetic choice of treatment. This article describes the prosthodontic rehabilitation of Maxillary Kennedy class I partially edentulous patients. In these two cases, the patients had a small number of teeth and they were restored by the combination of a removable partial denture and dental implants.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.2
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• pp.120-125
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• 2018

Conventional denture impression techniques have limitations for edentulous patients with severe alveolar bone resorption and can cause problems from excessive border extension. Especially when a patient has movable tissue it is difficult to make accurate impression, thus might interrupt stable seating of complete denture. Fabrication of complete denture using closed mouth technique for edentulous patient with severe ridge resorption is thought to provide better stability and retention. In this case, an 86-year-old patient had both edentulous jaws with epulis fissuratum on maxillary anterior ridge and severe mandibular ridge resorption. Thus, tentative vertical dimension was determined by using Centric trayand individual tray attached with gothic arch tracer was fabricated. Complete denture was fabricated using closed mouth technique and the patient was satisfied with better stability and retention of the complete denture.

• Imaging Science in Dentistry
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• v.46 no.2
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• pp.93-101
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• 2016

Purpose: The objective of this study was to investigate the effect of varying resolutions of cone-beam computed tomography images on the accuracy of linear measurements of edentulous areas in human cadaver heads. Intact cadaver heads were used to simulate a clinical situation. Materials and Methods: Fiduciary markers were placed in the edentulous areas of 4 intact embalmed cadaver heads. The heads were scanned with two different CBCT units using a large field of view ($13cm{\times}16cm$) and small field of view ($5cm{\times}8cm$) at varying voxel sizes (0.3 mm, 0.2 mm, and 0.16 mm). The ground truth was established with digital caliper measurements. The imaging measurements were then compared with caliper measurements to determine accuracy. Results: The Wilcoxon signed rank test revealed no statistically significant difference between the medians of the physical measurements obtained with calipers and the medians of the CBCT measurements. A comparison of accuracy among the different imaging protocols revealed no significant differences as determined by the Friedman test. The intraclass correlation coefficient was 0.961, indicating excellent reproducibility. Inter-observer variability was determined graphically with a Bland-Altman plot and by calculating the intraclass correlation coefficient. The Bland-Altman plot indicated very good reproducibility for smaller measurements but larger discrepancies with larger measurements. Conclusion: The CBCT-based linear measurements in the edentulous sites using different voxel sizes and FOVs are accurate compared with the direct caliper measurements of these sites. Higher resolution CBCT images with smaller voxel size did not result in greater accuracy of the linear measurements.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.4
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• pp.307-313
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• 2017

The object of this case report is to introduce milled zirconia bar and PEKK female part made by CAD/CAM technology for bar attachment implant supported overdenture in maxillary edentulous patients. For over 2 years, in terms of function and esthetics, satisfactory result was obtained. Esthetically and functionally satisfactory results were obtained in periodic follow up check.