• Journal of the korean academy of Pediatric Dentistry
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• v.3 no.1
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• pp.12-17
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• 1976

The study is about the effect of tetracycline-HCl on the amelogenesis and the dentinogenesis of the albino rats by means of histochemistry and fluorescence microscopy. Females in oestrus were mated overnight and examined the next morning for evidence of copulation. The mothers were intraperitonealy injected with a single dose of tetracycline-HCl from the eighth to tenth day of gestation. The heads of new born rats were fixed in Carnoy's solution and 10% formalin solution. The staining methods were alizarin red S stain, PAS reaction, colloidal iron reaction, Morin's stain and hematoxylin-eosin stain, The results were as follows: 1. By the single injection of tetracycline, the matrix formation of enamel and dentin were disturbed, and the shape and arrangement of ameloblast and odontoblast were distorted. 2. It seemed that, with the higher dose of tetracycline, the positive materials of PAS reaction were increased in the disturbed enamel and dentin matrix, but those of alizarin red S stain and colloidal iron reaction were decreased. 3. The fluorescence intensity in the disturbed enamel and dentin matrix were higher than the other areas and appeared to increase gradually with the higher dose of tetracycline.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.12 no.2
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• pp.66-71
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• 2016

Intellectual disability is accompanied by a high incidence of congenitally absent teeth and supernumerary teeth, and is observed more frequently than are disorders of location and order during delayed eruption, when accompanied by other symptoms. Furthermore, it is associated with a higher occurrence of dental anomalies such as conical teeth, microdontia, and amelogenesis imperfecta. As it is difficult to obtain adequate cooperation from patients with intellectual disabilities, physical restraint and conscious sedation using medication and general anesthesia can be considered. Reshaping of conical teeth with resin composite may be helpful to rehabilitate patients with oligodontia and a conical tooth shape. Diagnostic wax-up and a silicone matrix formed the basis for the successful reconstruction of the anterior teeth. This case describes the treatment of a patient with intellectual disability who had oligodontia and conical-shaped incisors. Under general anesthesia, the patient was treated using direct composite resin restoration.

• Clinical and Experimental Pediatrics
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• v.46 no.6
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• pp.606-609
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• 2003

Goltz syndrome(focal dermal hypoplasia) is a rare disorder characterized by ectodermal and mesodermal dysplasia described in 1962 by Goltz. In Korea, one case of Goltz syndrome was reported in 1994. The inheritance mode is mostly X-linked dominant. Skin abnormality is the most common manifestation including hypoplasia of the dermis. Skeletal involvement such as syndactyly, polydactyly, scoliosis, kyphosis and spina bifida occulta may be present, also ocular and dental abnormalities are reported. Radiologic findings are the osteopathy and striation of the long bone. We experienced a case of Goltz syndrome in a 9-year old female who was presented with right side hypotrophy, focal dermal hypoplasia, ocular(anidria, microcornea), dental(oligodontia, amelogenesis) and skeletal(syndactyly) abnormalities. Skin biopsy was performed and showed decreased expression of type I collagen gene with Northern blotting.

• Imaging Science in Dentistry
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• v.44 no.1
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• pp.7-13
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• 2014

Purpose: This study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 7- to 35-year-old patients by using panoramic radiographs. Materials and Methods: This cross-sectional study was conducted on 1649 people in Hamadan City, in 2012-2013. The prevalence of four types and 12 subtypes of dental anomalies was evaluated by two observers separately by using panoramic radiography. Dental anomalies were divided into four types: (a) shape (including fusion, taurodontism, and dens invagination); (b) number (including hypodontia, oligodontia, and hyperdontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia); and (d) position (including displacement, impaction, and dilacerations). Results: The reliability between the two observers was 79.56% according to the Kappa statistics. The prevalence of dental anomalies diagnosed by panoramic radiographs was 29%. Anomalies of position and number were the most common types of abnormalities, and anomalies of shape and structure were the least in both genders. Anomalies of impaction (44.76%), dilacerations (21.11%), hypodontia (15.88%), taurodontism (9.29%), and hyperdontia (6.76%) were the most common subtypes of dental anomalies. The anomalies of shape and number were more common in the age groups of 7-12 years and 13-15 years, respectively, while the anomalies of structure and position were more common among the other age groups. Conclusion: Anomalies of tooth position were the most common type of dental anomalies, and structure anomalies were the least in this Iranian population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies.

• Applied Microscopy
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• v.46 no.1
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• pp.58-66
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• 2016

Thymosin ${\beta}4$ ($T{\beta}4$) has been recently reported to play a role in dentinogenesis by regulating the expression of dentin matrix proteins. Based on previous studies, it is hypothesized that $T{\beta}4$ is associated with the formation of the enamel matrix and thus plays an important role in ameloblast. However, there is no report on the function of $T{\beta}4$ during tooth development so far. Therefore, in this study, we aimed to investigate the expression of $T{\beta}4$ and its function in ameloblasts during mouse tooth development. $T{\beta}4$ was expressed strongly in the tooth bud at the bud stage and in the dental lamina and oral epithelium at the cap stage. In advanced bell stage at postnatal day 4, large elongated ameloblasts were observed and the expression of the $T{\beta}4$ protein was the highest, with the enamel being was thicker than that in the early bell stage. The length of ameloblasts increased from the presecretory to the secretory stage and decreased from the maturation to the protective stage. These results suggest that $T{\beta}4$ participates not only in the proliferation of oral epithelial cells during the early stage of tooth development but also regulates enamel protein secretion in ameloblasts and enamel mineralization.

• Journal of dental hygiene science
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• v.12 no.5
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• pp.486-492
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• 2012

Immunostaing intensity of Dynamin II protein in ameloblast during mouse tooth development showed a significant increase of 48% at the postnatal day 3 and a significant increase of 50% at the postnatal day 5 as compared with the postnatal day 1, but showed a significant decrease of 16% at the postnatal day 7 and a significant decrease of 12% at the postnatal day 10 as compared with the postnatal day 1. From the above results, Dynamin II had relevance to secretion of amelogenin, ameloblastin, enamelin and matrix metalloproteinase-20 proteins for enamel formation in ameloblast. Dynamin II may be involved in the transport of vesicles containing proteins for enamel formation through the acceleration of vesicular formation and may be had a good possibility of secretory regulation of proteins for enamel formation in ameloblast. Therefore, Dynamin II have potential for being used in the field of gene theraphy for periodontal disease and in the regeneration for enamel and dentin tissues lost to dental caries.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.1
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• pp.63-70
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• 2021

Using computer-aided design and manufacturing technique improve quality of treatment in many aspect. This case reports the complete mouth rehabilitation of a patient with amelogenesis imperfecta utilizing digital technology. Clinical examination revealed loss of mastication due to insufficient occlusal stop, missing teeth, interdental spacing due to microdontia, insufficient overbite, and etc. Full veneer crowns for teeth were selected, followed by a fixed partial denture and implant placement was done using CAD-CAM guide template with bone graft for partially edentulous space. Definitive restorations were duplicated by double scanning provisional restorations and successfully delivered to the patient. These full mouth rehabilitation procedures resulted in satisfactory outcomes for the patient functionally and aesthetically.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.473-480
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• 2007

The dentigerous cyst originates through alteration of stellate reticulum after amelogenesis has completed, with accumulation of fluid between the layers of the reduced enamel epithelium or between this epithelium and the tooth crown. Its incidence is relatively high on 10s or 20s of age and it is always related to the unerupted crown. Generally, it has no symptom, however, if the cyst is large or accompanied with pus formation, swelling and pain may occur. In radiographic findings, it shows impacted crown surrounded by well defined unilocular radiolucent lesion and occasionally displacement of adjacent teeth or root resorption. The goal of treatment is complete elimination of abnormal tissue preserving the tooth involved in the cyst. Enucleation and marsupialization are commonly used for the treatment. Marsupialization is the procedure which removes the partial portion of the cystic wall and connects with the oral mucosa. As the pressure in the cyst decreases, bone regeneration takes place in the defect area and cystic wall converts into normal mucosa. This procedure, however, is the most conservative procedure which allows the protection of adjacent important structures. If the eruption space is sufficient, then inducing the eruption of the permanent tooth in the cyst is also possible. In following cases, dentigerous cyst was diaganosed after clinical and radiographic examination. Marsupialazation was done to remove the cyst and induce the tooth, which was in the cyst, to erupt into the oral cavity.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.3
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• pp.481-488
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• 2009

Buckley's formocresol was first introduced as a pulp medicament in 1904, and since 1930, it has been the treatment of choice for primary molar pulpotomies. Formocresol has fixation effect of pulp tissue and high clinical success rate. But side effect such as displacement and loss of permanent successor, amelogenesis imperfecta, cyst formation, mutation by general absorption, possibility of cancer induction have been reported. Of those, dentigerous cyst can form in the periradicular region after formocresol pulpotomy caused by an alteration of the reduced enamel epithelium, which result in fluid accumulation between the epithelium and the tooth crown. The present case describes a 6-year-old girl who had accidentally discovered in the panoramic radiograph a single, well-defined, radioluscent area enclosing the second unerupted mandibular premolar. The second left primary molar had been pulpotomizied 3 year before. Surgical treatment was carried out, the primary molar was extracted and cystectomy was performed under local anesthesia. In the extracted second primary molar, formocresol cotton pellet was left in the pulp chamber. Histologic study confirmed the suspected diagnosis of dentigerous cyst. This report present a case of dentigerous cyst associated with inadequate formocresol pulpotomized deciduous molar.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.4
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• pp.669-676
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• 1999

The dentigerous cysts originate through alteration of the reduced enamel epithelium after amelogenesis is completed, with accumulation of fluid between the layers of the enamel epithelium, or between this epithelium and the tooth crown. Next to the radicular cyst, they are the second most common type of odontogenic cyst. They occur over a wide age range with a peak frequency in the 2nd to 3rd decade. A substantial majority involve the mandibular third molars, followed in order of frequency by the maxillary permanent canines, mandibular second premolars, and maxillary third molars. With regard to the treatment of these cysts, the marsupialization procedure with obturator is recommended during the age when the eruptive force of the teeth is still strong. It can be effective when preservation of the displaced teeth is desirable. We treated the dentigerous cyst by marsupialization with obturator and guided the eruption of involved teeth to normal position. And we got the results as follows : 1. Severely dislocated teeth associated with dentigerous cyst erupted into proper position. 2. The enamel hypoplasia and the root deformity were observed some cases. 3. The bone expansion and defect were healed without infection and recurrence.