• The Journal of Korean Academy of Prosthodontics
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• v.43 no.2
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• pp.191-203
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• 2005

Statement of problem. In Korea, the preliminary impression trays for dental and edentulous maxillae are manufactured on the base of the statistical value of Westerners. There had been less study on the dental and edentulous arches of Koreans. Purpose. The purpose of this study was to evaluate an average dental cast, preliminary impression trays, three-dimensional relation of dental and edentulous maxilla of Koreans Material and methods. The subjects for this study were 173 dental casts of maxilla (dental: 52, edentulous : 146) with ages $18\{\sim}60$ years old. Each of the master casts was measured 69 measuring points on the dental cast or maxilla, and 46 measuring points on the edentulous cast of maxilla with three-dimensional digital measuring machine. Each measuring points were analysed and were overlapped, that three dimensional dental graphic manufactured by CAD/CAM system. Results. 1. A standard of distribution to alveolar bone were width between left and right buccal border lines of the standard 3/4 line. The mean value of dental and edentulous casts were 67.27mm, 63.49mm respectively. 2. Morphological classification of dental casts were divided into three groups or V-shape, O-shape, U-shape, that proportion of distribution were 17%, 16%, 67%, respectively. Dimensional classification of the dental casts were divided into five groups of less than 63mm, 63 up to 65mm, 65 up to 67mm. 67 up to 69mm, more than 69mm, respectively. 3. Morphological classification of edentulous casts were divided into three groups or V-shape, O-shape, U-shape, that proportion of distribution were 18%, 17%, 65%, respectively Dimensional classification of the edentulous casts were divided into five groups of less than 57mm, 57 up to 61mm, 61 up to 65mm, 65 up to 69mm, more than 69mm, respectively. 4. Mean dental and edentulous cast of maxilla were overlapped, the proportion of bone resorption to alveolar bone is higher than that of palatal bone, its difference were higher anterior 2/4 area than posterior 3/4 area. Conclusion. It obtains information of preliminary impression trays for dental and edentulous maxilla of Koreans.

• 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.

• Imaging Science in Dentistry
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• v.31 no.3
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• pp.165-173
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• 2001

Objectives : To evaluate the absorbed and effective doses of spiral and computed tomography for the dental implant planning. Materials and Methods: For radiographic projection, TLD chips were placed in 22 sites of humanoid phantom to record the exposure to skin and the mean absorbed dose to bone marrow, thyroid, pituitary, parotid and submandibular glands and nesophagus. Effective dose was calculated, using the method suggested by Frederiksen et al.. Patient situations of a single tooth gap in upper and lower midline region, edentulous maxilla and mandible were simulated for spiral tomography. 35 axial slices (maxilla) and 40 axial slices (mandible) with low and standard dose setting were used for computed tomography. All the radiographic procedures were repeated three times. Results: The mean effective dose in case of maxilla was 0.865 mSv, 0.452 mSv, 0.136 mSv and 0.025 mSv, in spiral tomography of complete edentulous maxilla, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). That in case of mandible was 0.614 mSv, 0.448 mSv, 0.137 mSv and 0.036 mSv, in spiral tomography of complete edentulous mandible, computed tomography with standard mAs, computed tomography with low mAs and spiral tomography of a single tooth gap (p<0.05). Conclusions: Based on these results, it can be concluded that low mAs computed tomography is recommended instead of spiral tomography for the complete edentulous maxilla and mandible dental implant treatment planning.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.5
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• pp.361-366
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• 2009

Purpose: The purpose of this retrospective report was to analyze long-term survival rate of sintered porous-surfaced dental implant ($Endopore^{(R)}$ Dental Implant system, Innova Corporation, Toronto, ON, Canada). Methods: 61 partially edentulous patients were received a total of 127 Endopore dental implants in the maxilla. Of the 127 implants, 24 implants were restored with individual (ie, non-splinted) crowns, while 103 implants were splinted to other implants. Medical records and radiographs were evaluated and analyzed by the cumulative survival rate, location of implants, implants length and diameter, crown/implant ratio and whether the implant was splinted. Chi squire test was used statistically. Result: Of the 127 implants, 8 implants (6.3%) were removed and and cumulative survival rate was 93.7%. Conclusion: Endopore implants showed satisfactory results after up to 8 years function periods in the edentulous posterior maxilla.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.39
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• pp.2.1-2.6
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• 2017

Background: All clinicians are aware of the difficulty of installing a dental implant in posterior maxilla because of proximate position of maxillary sinus, insufficient bone width, and lower bone density. This study is to examine which factors will make the implantation in the posterior maxilla more difficult, and which factors will affect the postoperative implant stability in this region. Methods: Five hundred seventy-three fixtures on the maxilla posterior were included for this study from all the patients who underwent an installation of the dental implant fixture from January 2010 to December 2014 at the Department of Oral and Maxillofacial Surgery in Pusan National University Dental Hospital (Yangsan, Korea). The postoperative implant stability quotient (ISQ) value, fixture diameter and length, presence of either bone graft or sinus lift, and graft material were included in the reviewed factors. The width and height of the bone bed was assessed via preoperative cone beam CT image analysis. The postoperative ISQ value was taken just before loading by using the OsstellTM $mentor^{(R)}$ (Integration Diagnostics AB, Gothenburg, Sweden). The t test and ANOVA methods were used in the statistical analysis of the data. Results: Mean ISQ of all the included data was 79.22. Higher initial bone height, larger fixture diameter, and longer fixture length were factors that influence the implant stability on the posterior edentulous maxilla. On the other hand, the initial bone width, bone graft and sinus elevation procedure, graft material, and approach method for sinus elevation showed no significant impact associated with the implant stability on the posterior edentulous maxilla. Conclusions: It is recommended to install the fixtures accurately in a larger diameter and longer length by performing bone graft and sinus elevation.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.10 no.1
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• pp.104-113
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• 2001

This article described a procedure for fabricating an esthetic gingival porcelain restoration as an implant-supported fixed prosthesis for edentulous maxilla. Alternative treatments for fully edentulous patients include an implant-supported overdenture or a fixed implant-supported prosthesis with bilateral distal cantilevers. But, from a functional and biomechanical point of view, the fixed implant-supported prosthesis with posterior cantilevers or implant-supported tissue-borne overdenture do not significantly improve masticatory effectiveness compared with a distributed implant restoration as a fixed implant-supported prosthesis. The fact that the prosthesis is supported by distributed implants over eight for edentulous maxilla in general, provides increased masticatory efficiency as a fixed restoration and similar gingival appearance with esthetic gingival porcelain. It is also detachable by dentist to allow easier after-care of soft tissue and the prosthesis.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.8 no.1
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• pp.46-59
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• 1999

A fixed bridge is preferred as a prosthetic option supported by oral implants. However, it is very difficult to re tore edentulous maxilla with fixed prosthesis in cases with improper position and angulation of fixtures, abnormal jaw relation, and need for proper lip support. Six Br${\aa}$nemark implants were installed in edentulous maxilla opposing mandible with natural dentition. A removable hybrid prosthesis attached to a bar milled by 6 degrees was therefore designed to overcome such disadvantages of fixed prosthesis. Lateral stabilization of removable prosthesis was obtained by framework closely fitting the milled bar. Support for the prosthesis was ensured by three elevated areas on the bar. Two precision attachments(CEKA REVAX) provided appropriate direct and indirect retention without influencing support. A clinical and laboratory procedure was presented.

• The Journal of Advanced Prosthodontics
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• v.6 no.1
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• pp.53-59
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• 2014

PURPOSE. The aim of this study was to obtain statistical data on the residual bone height at different natural tooth positions by panoramic radiography in edentulous Korean patients aged 60-90 years. MATERIALS AND METHODS. The study included the diagnostic panoramic radiographs of 180 randomly selected edentulous patients without systemic diseases affecting bone. The radiographic selection criteria included absence of obvious facial asymmetry, clearly visible anatomic structures, and no surgical and fracture history. The panoramic radiographs of 79 patients met these criteria and were used in the analysis. The same researcher processed all the radiographs by using a standardized method. The height of the residual bone was measured at 18 predetermined sites (7 in the maxilla and 11 in the mandible) on digitized and printed radiographs by using a Digimatic caliper, triangle, and ruler. Gender- and age-related differences were statistically analyzed by using the t-test and rank-sum test (${\alpha}=0.05$). RESULTS. The maxillary residual bone height did not show significant gender-related differences, but male patients had significantly higher residual bone in the mandible(P<.05). No significant height differences at the measured sites were noted among the 60s, 70s, and 80s age groups. CONCLUSION. Dentists should pay greater attention to older female edentulous patients because they are more prone to rapid residual bone resorption. Residual bone resorption may not be affected by age.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.152-159
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• 2016

Implant fixed prosthesis for the complete edentulous maxilla provides significant benefits in the aspects of functions and esthetics compared with the conventional denture. Implant supported fixed prosthesis are totally supported by implant, and thus stabilizes the prosthesis to the maximum degree as possible. Also, the improved retention and stability of fixed prosthesis enhance patients' psychological and psychosocial health. This clinical presentation describes a maxillary full arch implant-supported fixed prosthesis in complete maxillary edentulous patient who showed vertical and horizontal alveolar bone resorption in the anterior ridge. To rehabilitate the esthetics and proper lip support, the zirconia framework was fabricated and the pink porcelain was veneered to reproduce the natural gingival tissue. After 9 months of follow up, the restorations were maintained without complications and the patient was satisfied with the restoration both functionally and esthetically.

• 대한치과보철학회:학술대회논문집
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• 2002.11a
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• pp.120-120
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• 2002