• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.2
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• pp.145-156
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• 2010

Loss of posterior support may cause overloading and excessive wear of remaining teeth. Moreover, the extrusion of antagonistic teeth leads to the destruction of the occlusal plane. The loss of vertical dimension of occlusion (VDO) also emerges clinically, which may bring the loss of esthetic appearance and function. These patients who suffer from the loss of posterior support, often require vigorous periodontal treatments (osteotomy, crown lengthening) and extensive oral rehabilitation. Sixty three years old female patient visited for the prosthetic treatment of the posterior edentulous area. She had no other systematic disease and parafuctional habits for prosthetic treatment. Intraoral and radiographic examinations were done. The evaluation of VDO and vertical dimension of rest position were evaluated for proper prosthetic procedures and diagnostic wax up was done. As a result of diagnosis, VDO was increased by 2 mm considering the loss of VDO and space for the prosthetic treatment. After the pretreatments, initial preparation of teeth and provisionalization were carried out. Six weeks later of provisionalizaion, final preparation and impression was performed. Using the duralay resin copings, jaw relation was registered. The master cast was mounted and definitive restoration was fabricated. After the evaluation of esthetic and function, pick up impression for clinical remounting was done. Lucia jig was made for new jaw relation and occlusal adjustment on the articulator. Definitive restoration was delivered and the patient was periodically recalled for additional occlusal adjustment. From this case, the satisfactory functional and esthetic results through full mouth rehabilitation with increase vertical dimension were achieved.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.3
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• pp.224-235
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• 2013

A passively fitting prosthesis is an essential prerequisite to attain long-lasting success and maintenance of osseointegration. However, true "passive fit" can not be achieved with the present implant-supported prosthesis fabrication protocol. Many clinical situations are suitably treated with cantilevered implant-supported fixed restorations. The purpose of this study was to compare the stress distribution pattern and magnitude in supporting tissues around ITI implants with cantilevered, implant-supported, screw-retained fixed prosthesis according to the fitness of superstructures. Photoelastic model was made with PL-2 resin (Measurements, Raleigh, USA) and three ITI implants (${\phi}4.1{\times}10mm$) were placed in the mandibular posterior edentulous area distal to the canine. Anterior and posterior extended 4-unit cantilevered FPDs were made with different misfit in the superstructures. 4 types of prosthesis were made by placing a $100{\mu}m$ gap between the abutment and the crown on the second premolar and/or the first molar. Photoelastic stress analysis were carried out to measure the fringe order around the implant supporting structure under simulated loading conditions (30 lb).

• Restorative Dentistry and Endodontics
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• v.13 no.2
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• pp.323-334
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• 1988

The purpose of this study was to observe the effect of dentin surface conditioners on the dentin surfaces. Freshly extracted human molars were used in this study. They were stored at $4^{\circ}C$ saline solution before experiment. The crown portions of the teeth were cut in various directions by means of wet diamond point to expose dentin which include transverse, vertical oblique, horizontal and oblique cut to the long axis (Fig. 1). Each tooth was then mounted with self curing acrylic resin in brass ring to expose the flattened dentin surfaces. Final finish was accomplished by grinding the dentin specimens with wet No. 180 and No. 600 grit silicon carbide abrasive paper until a 6.0mm in diameter on a dentin surface was exposed without pulp exposure. The specimens were divided into 9 groups according to the modes of dentin treatment procedure. The following surface treatments were applied on these preparation surfaces; Group 1: unetched (control group) after finish with No. 600 silicon carbide abrasive paper. Group 2: etched with 30% phosphoric acid for 60s Group 3: etched with 10-3 solution for 60s Group 4: Cleaned with 5% NaOCl for 30s Group 5: applied Dentin Adhesit Group 6: cleaned with 5% NaOCl followed by applying the Dentin Adhesit$^{(R)}$ Group 7: applied Photo Bond on the unetched dentin followed by applying the Photo Clearfil Bright Group 8: Etched with 30% phosphoric acid followed by applying Photo Bond and Photo Clearfil Bright Group 9: etched with 10-3 solution followed by applying Photo Bond and Photo Clearfil Bright All the specimens were stored in $37^{\circ}C$ under 50% relative humidity for 24 hours before observations. The specimens in 7, 8, and 9 group, omitting the group 1 to 6, were demineralized in 10% HCl for 10s in order to observe the resin tags. All the specimens in each group were then dried at room temperature. The dried specimens were ion coated with Eiko ion coater (Eiko-engineering Co.), and observed in Hitachi S-430 Scanning electron microscope (Hitachi, Co. Tokyo) at 15KV. The following results were obtained as follows; 1. The smear layers were still remained in group 1,2,4,5, and 6. 2. There is no effect of 5% NaOCl and 30% phosphoric acid on the changes of dentin morphology 3. The dentin treated with 10-3 solution, indicating the tubules opened when the smear layer and the dental plug dissolved. 4. In case of applying the bonding agents the resin tag was not formed at the deep area of dentinal tubules, but in case of applying the Dentin Adhesit$^{(R)}$ that was not.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.1
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• pp.69-75
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• 2002

A number of techniques may be employed to reduce the discomfort of syringe or needle for dental care. The use of topical anesthesia is one such method. Topical anesthetics are applied to alleviate pain during many clinical procedures, such as injection of local infiltration anesthetics, primary tooth extraction, X-ray taking of sensitive patients, reducing gag reflex prior to impression taking. In children, placement of a rubber dam clamp, however, may cause significant discomfort for purpose of pit and fissure sealant and preventive resin restoration(PRR). A topical anesthetic would be beneficial to aid in rubber dam placement for this purpose. It has been suggested that all intra-oral topical anesthetics are equally effective on reflected mucosa, however EMLA(an acronym for eutectic mixture of local anesthetics), which was developed in the 1980s and produces surface anesthesia of skin, has been shown to be more effective than conventional topical anesthetics when used on attached gingivae. This report is topical anesthesized 4 case by EMLA cream, who showed better effect in reducing the pain of infiltration anesthesia, extraction of deciduous teeth, rubber dam clamp placement and reducing the pain of preformed crown adaptation.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.371-375
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• 2002

The calcifying odontogenic cyst(COC) showed diverse terminology or classification, clinicopathologic features as well as in its biologic behavior, although it was recognized as a distinct clinicopathologic entity. The epithelial lining of a COC appears to have the ability to induce the formation of dental tissues in the adjacent connective tissue wall, and that other odontogenic tumors may sometimes be associated with it. This case is a COC associated with a complex odontoma involving an impacted left maxillary lateral incisor in a 5-year-old female child. Radiographic examination revealed a well-demarcated radiolucent lesion partially occupied by a radiopaque mass, involving the left lateral incisor crown. The histologic sections showed a cystic cavity lined with ameloblastic epithelium containing ghost cell masses with admixed with complex odontoma components. The presence of mixed radiolucent-radiopaque lesion in children as observed in this case, the possibility of COC must be considered. In this case, there was no recurrence 1 year after enucleation and the space control is ongoing now.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.4
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• pp.701-704
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• 2004

In this case, we would like to discuss about the single rooted deciduous mandibular first molar. The deciduous mandibular molar of a five years old boy was shown to have a single root, bilaterally. Ordinarily, the maxilary molars have three roots and the mandibular molars have two roots. However, when the hertwig's epithelial root sheath do not invaginate properly during tooth development, root fusion can occur from the absence of root separation. Molars with fused roots not only have unfavorable crown to root ratio, but also according to many reports, have higher probability of having multiple congenitally missing teeth or dens invaginatus in the maxillary incisors, consequently requiring preventive dental treatment In addition, disorders such as ectodermal dysplasia, syndactyly, clinodactyly, bluish sclera can also be related to this condition. Root fusion is known to be of autosomal recessive inheritance. Up to date, single rooted molars have been reported several times in permanent dentitions but hardly in deciduous dentition, which is the motive for this paper.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.4
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• pp.260-269
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• 2019

The prolonged neglect of the posterior teeth missing area may cause mesial drift, extrusion, unexpected movement of the adjacent teeth and alveolar bone loss with occlusion collapse. Therefore it is recommended to treat that area by the prosthesis as soon as possible after tooth missing. However, if orthodontic treatment is applied to move the remained teeth, it can create improved biomechanical dentoalveolar environment. The use of the third molars in teeth missing area provides advantages as optimizing of prosthesis size. However, crown shape, location, soundness of the third molar and possible of eruption failure should be considered. In this case report, two patients closed a second teeth missing site and reduced the size of the first and second teeth missing area for an implant by protraction of impacted third molars. This case reports the considerations for closing or reducing the posterior teeth space with protracting the third molars by comparing two patients.

• Anatomy & Biological Anthropology
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• v.27 no.3
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• pp.155-163
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• 2014

This study aimed to investigate the cusp size and morphological characteristics of permanent mandibular molars in Koreans with reference to the hypoconulid, and to analyze the differences and correlations between both sexes as well as between first and second mandibular molars. We obtained data from dental casts of 110 adults (78 males and 32 females). Mesiodistal and buccolingual diameters of first and second mandibular molars, the area of five cusps (protoconid, metaconid, hypoconid, entoconid, and hypoconulid), as well as the total cusp area and occlusal table area were measured. Paired t-test was performed to analyze the morphological differences between first and second mandibular molars and the sex differences between both sexes using SPSS program. Crown diameters and cusp areas of mandibular first molars were larger than those of mandibular second molars in both sexes. The hypoconulid was the most variable in size and morphological pattern among the five cusps, and the first molars showed a higher incidence of hypoconulid than the second molars. Except for the entoconid area of the first molar (p=0.06) and the hypoconulid area of the second molar (p=0.24), all other mean values were larger in males than in females, demonstrating a significant sexual dimorphism. These data suggest that the teeth which develop late in ontogeny tend to be smaller in size and more variable in morphological characteristics.

• Journal of the korean academy of Pediatric Dentistry
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• v.48 no.2
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• pp.160-167
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• 2021

The purpose of this study was to investigate the prevalence and characteristics of pre-eruptive intracoronal radiolucencies (PEIR) from panoramic radiographs in Korean children and adolescents. This study examined panoramic radiographs of 3,000 patients aged between 5 and 14 years old who visited ten dental hospitals in Korea. The age and gender of the patients, the tooth type, the number of intracoronal radiolucent lesions, and the location and size of the lesions were recorded. The overall prevalence of patients with PEIR was 2.5%. The difference in the presence of PEIR between both genders was not significant. Within each tooth type, the mandibular first molar showed highest prevalence of PEIR (29.6%). The central part of the crown was the most frequently observed location of PEIR (56.8%). The size of the PEIR lesions was mostly limited to less than one-third of the thickness of coronal dentin.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.3
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• pp.276-282
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• 2022

Close communication between clinicians and dental technicians is an important factor in providing successful prostheses. The exchange of opinions with laboratories has mainly been in the form of written prescriptions and a photos, but it has been reported that information transmission may be limited. Currently, as digital technology-based prosthesis fabrication is common, 3D image objects can be stored on the web and can be easily viewed through a mobile web browser. In this article, we introduce cases where the design of the prosthesis was improved by designing the prosthesis using CAD software and reviewing the prosthesis designed with the clinical side through a web viewer. Through this protocol, it was possible to improve the occlusal surface and crown contour, the opposing teeth condition, the size of the gingival embrasure, and the shape of pontic. The process of sharing, discussing, and modifying the prosthesis design with the clinician and technician through a web viewer contributes to reflecting the diversity of oral conditions and individualized needs, thereby helping to make functional and esthetic prostheses.