• Journal of Technologic Dentistry
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• v.13 no.1
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• pp.21-26
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• 1991

The mesiodistal crown diameters and crown length of the permanent anterior teeth have been studied and analyzed about the mean size, S.D, S.E etcs from stone models of 100 Korean male and 74 female. From the study, the following conclusions were made : 1. Statistical differences of left and right teeth were not found in the mesio distal crown diameters and crown length of the permanent anterior teeth. 2. The mean values of mesiodistal crown diameters of permanent anterior teeth were slightly larger in male than in females and statistical differences of males and females were found in maxillary right central incisor, mandibular left canine, mandibular right lateral incisor and mandibular right canine. 3. The mean values of crown length of permanent anterior teeth were slightly larger in male than in female and statistical differences of males and females were found in mandibular left canine, mandibular right canine. 4. Mesiodistal crown diameters and crown length of maxillary left lateral incisors and right lateral incisors of female are larger than that of male.

• The Journal of Advanced Prosthodontics
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• v.12 no.4
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• pp.239-249
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• 2020

PURPOSE. The purpose of this study was to investigate survival rates of the implants used in implant assisted removable partial dentures (IARPDs). MATERIALS AND METHODS. The study was conducted on 21 patients who were treated with IARPDs. The mean follow-up period for IARPD patients ranged from 12 to 185 months (mean 47.9 months). A total of 58 implants were used for IARPDs in two different modalities: 41 for surveyed crowns and 17 for overdentures. The survival of implants was determined by clinical and radiographic evaluations considering relevant factors: location, RPD classification, opposing dentition, splinting, and implant diameter. RESULTS. The survival rate of total 58 implants was 93.1%: 95.1% for implants supporting surveyed crowns and 88.2% for implants used in overdentures. Considering only the implants supporting surveyed crown, regular diameter implants showed a higher survival rate than narrow or wide diameter implants. CONCLUSION. The survival rate of the implants used in IARPDs was 93.1% (surveyed crown: 95.1%, overdenture: 88.2%).

• Journal of Technologic Dentistry
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• v.31 no.1
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• pp.7-15
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• 2009

Purpose: This study was to propose the clear understanding for stress distribution of supporting bone by use of staggered buccal offset tripodal placement of fixtures of posterior 3 crown implant partial dentures. We realized posterior 3 crown implant fixed partial dentures through finite element modeling and analysed stress effect of implant arrangement location to supporting bone under external load using finite element method. Method: To understand stress distribution of 3 crown implant fixed partial dentures which have 2 different arrangement by finite element analysis. In each model, for loading condition, we applied $45^{\circ}$ oblique load to occlusal surface of crown and applied 100 N for 3 crown individually(total 300 N) for imitating possible oral loading condition. at this time, we calculated Von Mises stress distribution in supporting bone through finite element method. Result: When apply $45^{\circ}$ oblique load to in-line arrangement model, maximum stress result for 100 N for each 3 crown 47.566MPa. In tripodal placement, result for 1mm buccal offset tripodal placement implant model was maximum distributed load 51.418MPa, so result was higher than in-line arrangement model. Conclusion: In stress distribution result by placement of implant fixture, the most effective structure was in-line arrangement. The tripodal placement does not effective for stress distribution, gap cause more damage to supporting bone.

• Journal of Periodontal and Implant Science
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• v.36 no.4
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• pp.817-827
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• 2006

Purpose : This study was designed 1) to compare the perception of dental professionals and lay people with respect to minor variations in maxillary anterior tooth size and alignment and their relation to the surrounding soft tissues, and 2) to evaluate the normal tooth-gingiva topographical relationships in periodontally healthy young subjects, Materials and methods : Maxillary anterior teeth were intentionally diagrammed in varying degree of deviation with respect to one of three common anterior esthetic discrepancies including variations in crown length, shape of gingival margin, and length of interproximal contact, 17 images were generated to be preferentially selected by 2 groups consisting of dental professionals and lay people (total of 740). Smiling photographs of 120 dental students who had healthy periodontium were taken and the photographic images were analyzed to be classified as 17 kinds of altered image groups. Results : The results demonstrated noticeable difference between the varying levels of discrepancy. Both group preferred gingival margin of lateral incisor to be 0.5mm lower than that of central incisor. Lay people preferred the gingival margin shape that has 2/9 horizontal component of the crown width, while dental professionals preferred the gingival margin shape that has 1/9 horizontal component of the crown width. Lay people preferred longer length of the interproximal contact (two thirds of the crown length), whereas dental professionals preferred shorter length of the interproximal contact (half of the crown length). Photographic analysis of normal esthetic gingival topography revealed 2/9 horizontal component and short length of the interproximal contact which was of the hybrid nature of the preferences shared by lay people and dental professionals. Conclusion: The results of this study show that dental professionals and lay people demonstrated significant difference in their preference of dental esthetic components, which may then influence the decision making process by dental professionals with respect to designing the anterior esthetic gingival line.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.1
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• pp.45-49
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• 2015

In this clinical report, a simple and convenient conversion of a fractured metal-ceramic surveyed crown into a complete contour zirconia surveyed crown by using computer-aided design and computer-aided manufacturing technology for an existing partial removable dental prosthesis is described. The duplication of the original contours, morphology, and the rest seat of the existing metal-ceramic surveyed crown, into a complete contour zirconia surveyed crown under anticancer treatments were reported.

• Journal of Technologic Dentistry
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• v.10 no.1
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• pp.47-54
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• 1988

The purpose of this study is to evaluate the castability of Ni-Cr alloys for crown and bridge. New young, Hi-Crown and CB-80 which are widely used in dental laboratory were chosen, casting and increased the temperature of furnace 100$^{\circ}C$ of each 7 grades from 600$^{\circ}C$ to 1200$^{\circ}C$. The results are as follows : 1. CB-80 is the most prominent castability among the three Ni-Cr alloys which are Hi-Crown, New-young and Hi-Cr. 2. The good burning temperatures of casting for CB-8p are 900$^{\circ}C$, 100$^{\circ}C$ and 1100$^{\circ}C$ which are obtained four complate casting body of five former patterns. 3. The most proper burning temperature for three Ni-Cr alloys is 900$^{\circ}C$.

• Journal of Technologic Dentistry
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• v.22 no.1
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• pp.49-55
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• 2000

In manufacturing the all-ceramic crown whick look close to natural teeth, the effectiveness of the improved technique is expectected the technique of the heat treatment of gold plating coating die was experimented of a refractory cast model. The following results were obtainde 1. An advantage of build up on east die with out manufacturing veneer, crown, core, or masking(reduction of technical process, and retrenchment of time and money) 2. Esthetically more close to natural teeth than other technique 3. Easy to remove a refractors cast die 4. In manufacturing ceramo-metal crown the enomous effectiveness was obtainde on applying in the areas of cervical margin, the metal surface, and in the treatment of pinhole.

• The Journal of Advanced Prosthodontics
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• v.2 no.2
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• pp.50-53
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• 2010

BACKGROUND. In order to restore severely attrited teeth properly, surgical intervention in the form of a crown-lengthening procedure may be required. And also, proper diagnosis and treatment sequencing is critical to obtain a successful results. Adequate diagnostic wax-up ensures good esthetics and healthy periodontal tissue. CASE DESCRIPTION. This clinical case report describes a diagnostically based protocol for restoration on mandibular anterior teeth with crown lengthening procedure and the treatment of partially edentulous mandible combined with an edentulous maxilla. In addition, the effort to prevent the combination syndrome was described. CLINICAL IMPLICATION. An interdisciplinary diagnosis and examination through visualization of the desired results ensure conservative and more predictable outcome.

• Journal of Technologic Dentistry
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• v.23 no.2
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• pp.75-93
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• 2002

This research was preformed for the purpose of preparing the items of standard model of the national dental technician test base on the duty analysis of the dental technician. The results of the duty analysis for the dental technician follows. 1. The dental technician is a profession to make the oral function smooth through the dental supplement and equipment in a scientific method and the skilled technique. 2. The duty of the dental technician are determined as A. preparation for manufacture B. manufacture C. management of the place of the dental technology D. self-development. A. The field of "the preparation for manufacture" are determined as 1. to confirm work authorization 2. To confirm the working model, B. The field of "In manufacture" are determined as 1. to manufacture the temporary crown 2. to manufacture the inlay and crown & bridge prosthesis 3. to manufacture the porcelain fused metal crown prosthesis 4. to manufacture the all ceramic crown prosthesis 5. to manufacture the temporary denture prosthesis 6. to manufacture the partial denture prosthesis 7. to manufacture the complete denture prosthesis 8. to manufacture the attachment prosthesis 9. to manufacture implant prosthesis 10. to manufacture the removable orthodontic device, 11. to manufacture the fixed orthodontic device, 12. to manufacture the orthodontic study cast C. The field of "in management of the dental lab." are determined as 1. management 2. to control the dental lab. D. The field of "In the self-development" are determined as 1. to improve the professionalism 2. self-control. 3. The developing items selected under the duty evaluation of the dental technician are l7s in the manufacture preparation, 1,011s in the manufacture, 7s in the management for the dental technology, 5s in self-development, and in all together 1,040s

• The Journal of the Korean dental association
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• v.23 no.7 s.194
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• pp.585-591
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• 1985