• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.2
• /
• pp.218-224
• /
• 2010

The prevalence of developmental defects of enamel and lesios by post-orthodontic decalcification has been reported with increasing frequency. Even though there have been increasing interests and clinical challenges in esthetic improvement of these lesions, few of studies were reported for using non-invasive approach which is a very significant matter for child and young adults. This study was conducted to assess clinical effect on the improvement in color of these lesions via resin infiltration method developed as minimum invasive technique for white spot. For the 38 maxillary anterior teeth with calcification problem, the changes in color between before- and after- infiltration treatment, were evaluated and summarized as following. 1. A week after infiltration, 25% of developmental defects and 61% of decalcification lesions were improved in color as the value of ${\Delta}E $ below 3.7. 2. 40% of the developmental defects and 6% of decalcification lesions showed no significant change. 3. The developmental defects showed more remarkable changes in color 1 week after infiltration rather than immediately after the treatment. From our study results, it is considered that the amount of color improvement depended on the depth of lesion. In other words, for the lesion having more depth than the depth infiltrant resin can penetrate into, infiltration treatment showed no significant effect. Therefore, for clinical indication of resin infiltration treatment, further research on precise measurement technique of lesion depth is strongly required.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.31 no.1
• /
• pp.34-40
• /
• 2004

Unerupted maxillary anterior teeth is not a common case, However it may present practitioners with management problem. The cause of impaction is considered to be multifactorial, and local cause is the most common. These impacted teeth require surgical intervention, removal, transplantation, or surgical exposure, with or without orthodontic traction to align the malpositioned tooth. The preferred option is surgical exposure and orthodontic correction. Surgical intervention and orthodontic correction should not be delayed to avoid unnecessary difficulties in aligning the tooth in the arch. Surgical exposure should be performed with the intent of providing sufficient attached gingiva rather than simply uncovering the crown, which results in only alveolar mucosal attachment. Attached gingiva is essential to secure the gingival tissues to the adjacent teeth at the dentogingival junction. Thus preventing loss of periodontal tissues as a result of the pull of the surrounding soft tissues and facial muscles. Labially impacted maxillary anterior teeth uncovered with an apically positioned flap technique have more un- esthetic sequelae than those uncovered with a closed-eruption technique. In the case of severly displaced impacted teeth, autotransplantation ensures preservation of the alveolar bone and will facilitate future placement of an osseointegrated implant once growth has ceased or if ankylosis/resorption of the transplant occurs.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.28 no.1
• /
• pp.180-184
• /
• 2001

Cleidocranial Dysplasia(CCD) is an autosomal dominant human bone disease characterized by abnormal clavicles, patent sutures and fontanelles, and dental anomalies. Among dental anomalies, it is characterized that permanent dentition is severly disturbed due to multiple supernumerary teeth and abnormalities of tooth morphology. A eight-year-old female patient diagnosed as cleidocranial dysplasia visited in our hospital. Upon clinical oral exam, retained deciduous teeth, constriction of dental arch, anterior cross bite, and multiple dental caries were observed. In the dental panoramic radiograph, retained deciduous teeth and multiple supernumerary teeth in the maxilla and the mandible were found. In the cephalometric radiograph, open sutures and wormian bones were seen. In the chest P-A view absence of clavicles was observed. The cleidocranial dysplasia patients have eruption problems in permanent dentition both in regions with and without supernumerary teeth. The severely delayed or arrested eruption of permanent teeth has been ascribed to various factors : 1) The presence of multiple supernumerary teeth, 2) malformed roots with lack of cellular cementum, 3) the jaw bone being too dense, and 4) abnormal resorption of bone and primary teeth. Formation and maturation of primary teeth in cleidocranial dysplasia are normal, whereas the permanent dentition has various anomalies. Therefore, dentists should understand the development of dentition in cleidocranial dysplasia, and treat them in proper time.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.4
• /
• pp.555-560
• /
• 2002

Replantation may be a treatment choice for a completely avulsed tooth caused by a traumatic injury. The outcome of replantation depends on the following factors ; minimal damage to pulp and periodontal membrane, the length of time the avulsed tooth was out of the mouth, how the tooth was stored, the level of root formation, etc. The time from the act of avulsion of the tooth to the actual replantation is especially important. Generally, when replanted within 30 minutes, more than 90% of the cases succeed, but when the time is between 30 to 90minutes, 43%, and greater than 90 minutes, 7%. This is a case of a replanted tooth with relatively good prognosis by ankylosis though there was a great time lapse since the tooth was avulsed. Though such treatment lead to loss of the tooth, in cases of children or adolescents, this treatment is meaningful, because it may earn time until any definitive therapy, functionally stimulate the alveolar bone to retain its height for a better prognosis for future treatment, and act as space maintainer.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.29 no.4
• /
• pp.574-578
• /
• 2002

Mesiodens is developmental tooth anomaly which is commonly found in clinical pediatric dentistry. however, it may cause many partial problem in tooth alignment when congenitally missing teeth was accompanied by mesiodens. The terms, concomitant hypodontia and hyperdontia' and oligo-pleiodontia' have been used to describe the condition in witch developmental absence of teeth and supernumerary teeth are present in the same individual. Only a few case reports of this rare condition which is opposite developmental phenomena exist in the literature. The purpose of this study is survey of congenitally missing teeth in mesiodens case and to compare previous literature of congenitally missing teeth in normal. The subjects were 310 children(247 male and 63 female) at the age from 5 to 12 years visiting the Department of Pediatric Dentistry, Pusan National University Hospital with mesiodens for last 3 years. With their pantomograms we studied congenitally missing teeth except permanent 3rd molar. 1. The preference of congenitally missing teeth in mesiodens cases was revealed to be 17.1%(53 out of 310 in total), and there was a higher prevalence in females(22.2%) than in males(15.8%). 2. The most frequently missing teeth were maxillary lateral incisors(22.7%) and mandibular second premolars(22.7%), followed by maxillary second premolar(17.3%), and mandibular lateral incisors(16.0%). There was no significant differences between maxilla(49.3%) and mandible(50.7%). 3. In number of congenitally missing teeth per person, 69.9% had one missing tooth, 22.7% had two missing teeth and 9.4% had three missing teeth.

• Korean Journal of Cleft Lip And Palate
• /
• v.13 no.1
• /
• pp.1-10
• /
• 2010

구순구개열은 선천성 악안면 기형중에서 발생률이 가장 높은 질환이며 특히 동양인에게 높은 빈도로 발생된다. 그리고 순구개열에서는 파열부 조직의 선천적 상실과 파열부 봉합 수술 후 형성된 반흔에 의한 상악골의 열성장과 상악궁의 협착, 코의 형태 이상, 등과 함께 치아의 수, 크기와 형태 및 맹출 이상도 높은 빈도로 동반된다. 선천성 치아 발육 이상이 구순열 또는 구개열 가진 환자에게서 종종 보고되고 있다. 이런 치아 이상은 과잉치, 결손치, 크기, 형태, 맹출시기, 법랑질 광화 등의 많은 특징을 포함한다. 이번 연구의 목적은 다음과 같다. 1. 구순열 또는 구개열을 가진 환자의 선천성 치아 결손 발병률을 결정하여 정상인과 비교하는 것이다. 2. 상하악에서 파열이 있는 부위와 없는 부위의 제2소구치 결손가능성을 비교 하는 것이다. 구강악안면외과에서 구순구개열로 진단한 환자 중 2005년 1월~2009년 8월까지 전북대학교 구강악안면외과에서 치조열부위 자가골이식수술을 받은 32명의 환자로 초진시의 교정 chart, 구강악안면외과 chart, x-ray(파노라마, 치근단사진, 교합사진(상악), 석고 모델, 구강내 외 임상사진을 사용하여 순구개열군 별로 매복치, 과잉치, 결손치, 왜소치의 유무와 위치를 조사하여 다음과 같은 결론을 얻었다. 1. 결손치는 비교적 높은 발생빈도(53.1%)를 보였으며, 치아별 발생빈도는 상악 측절치와 상악 제2소구치, 하악 제2소구치 순이었다. 구순구개열군이 구순치조열군에 비해 발생률이 높게 나타났다. 그리고 구순구개열군 내에서 양측성이 편측성에 비해 결손치의 발생률이 높게 나타났다. 2. 왜소치는 71.6%에서 발견되었으며, 치아별 발생빈도는 상악측절치에서 가장 많았다. 구순치조열군이 구순구개열군에 비해 발생률이 높게 나타났다. 3. 치조열을 가진 환자에 있어 상/하악간 제2소구치의 선천적 결손에 유의한 차이가 있었다. 4. 구순구개열이 인접한 상악측절치의 발생중인 미성숙 조직에 영향을 미치며 파열부위와 좀 더 떨어져 있는 상악 제2소구치에도 일정한 영향을 미침을 이번 연구를 통해 다시 확인할 수 있었다.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.28 no.4
• /
• pp.654-660
• /
• 2001

Dentinogenesis imperfecta is an example of an inheritable dentinal defect originating during the histodifferentiation stage of tooth development, with involvement of the primary and permanent teeth. Shields, Bixler and El-Kafrawy proposed three types of Dentinogenesis imperfecta : Type I, II, III. Witkop reported a prevalence of 1 in 8000 with the trait, and no significant difference between male and female. Affected teeth have red-brown discoloration often with distinctive wearness of occlusal surface of posterior teeth and incisal surface of anterior teeth. Once enamel seperated from underlying defective dentin, the dentin demonstrates significantly acclerated attrision. Radiographically, the teeth have thin roots, bulbous crown, cervical constriction, and obliteration of the root canals and pulp chambers. In primary dentition periapical lesions or multiple root fractures are often observed. In successive generations the phenotypes of discoloration and wearness of teeth occurred, and one of the patient's subships, 10 year-old sister, showed general discoloration of her teeth and mild wearness. In this case, a 4 year-old male reported to the Yonsei University Pedodontics clinic, with a chief complaint of discolored teeth. The teeth showed generally yellowish-brown discoloration and moderate wearness. In radiographic features, obliteration of pulp, bulbous crown, and short roots were observed. It was diagnosed as Dentinogenesis imperfecta. The posterior teeth were restored with Stainless Steel Crown, and defective incisors including left upper primary central incisor which was extracted due to a root fracture with Open-faced Stainless Steel crown.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.1
• /
• pp.109-116
• /
• 2010

Impaction is defined as a cessation of the eruption of a tooth caused by a clinically or radiographically detectable physical barrier in the eruption path or by an ectopic position of the tooth. The reasons for impaction of the maxillary central incisor are supernumerary tooth, odontoma, ectopic position of tooth germ, dilacerated tooth and so force. Impacted tooth cause space loss due to proximal movement of adjacent tooth, malocclusion, root resorption of adjacent tooth, cyst formation, so careful observation and early detection is important and exact treatment should be applied to prevent these results. The treatment options of impacted tooth include induction an eruption through extraction of deciduous tooth or surgical exposure, reposition of impacted tooth by surgical method or orthodontic treatment. Orthodontic traction is recommended when an eruption does not happen after removal of barrier or surgical exposure, when eruption path is too transpositioned to be corrected spontaneously so eruption does not expected. In these cases, traction of impacted maxillary central incisor was carried out using orthodontic method with closed eruption technique and it showed good clinical results so we report these cases.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.46 no.3
• /
• pp.239-246
• /
• 2019

The purpose of this study was to examine dental complications and to evaluate the effects of initial treatment age, treatment modalities, and treatment duration on the disorder after radiation and chemotherapy in pediatric cancer patients. For 93 children with clinical and radiographic data, the number of teeth, the morphology of teeth, the shape of the roots, and development status of the dentition were evaluated. Dental development disorders were found in 61.3% of the children. The mostly found abnormality was root deformity with the prevalence of 31.2%. In children submitted to the therapy before the age of 6, the number of missing teeth (p = 0.029) and microdontia (p = 0.003) were greater compared to the children who started to receive the treatment after the age of 6. The combination of radiation and chemotherapy showed significantly greater incidences of missing teeth (p = 0.030), microdontia (p = 0.046), and root deformity (p = 0.009) when compared with the sole application of chemotherapy. When the children were submitted to anticancer therapy for 18 months or longer duration, greater number of missing teeth (p = 0.032), microdontia (p = 0.011), root deformity (p = 0.025), and total number of teeth affected (p = 0.036) were observed compared with duration less than 18 months. The number of dental abnormalities increased when the children were treated at earlier ages, with combination of radiation and chemotherapy, and for longer period of time.

• Applied Microscopy
• /
• v.34 no.2
• /
• pp.145-157
• /
• 2004

The aim of the present study was to examine in detail, both at light and electron microscopical levels, the morphological variations in ameloblast of the fetal rat incisor enamel organ. Rats were started on distilled water at the beginning of pregnancy. The pups were sacrificed 11 days after delivery and animals were perfused intravascularly with glutaraldehyde and the incisors were removed. To examine on the ultrastructure of the ameloblast, the study employed primary light microscopy but electron microscopy was used to clarify some of the light microscopic finding. Longitudinal sections through the incisors of the rat show a continuous layer of ameloblasts on the labial surface of the tooth. This layer contains the entire sequence of developmental stages in enamel production. The ameloblast layer was divided into three main zones: 1) Presecretory zone, region of ameloblasts facing pulp. 2) Secretory zone, region of inner and outer enamel secretion. 3) Maturation zone, region of reduced ameloblasts. In particularly, the present study has shown that two distinctively different types of ameloblasts appear in the enamel organ during enamel maturation in the rat incisor. These two types have been designated ruffle-ended ameloblasts (rAB) and smooth-ended ameloblasts (sAB). The fluoride produces marked alteration in the fine structure of ameloblast from teeth of young rats, such as large confluent distensions of the endoplasmic reticulum and swelling of isolated mitochondria. This experimental data suggested that exposure prolonged of animal to high level of fluoride appears to induce a few dramatic changes in the normal appositional growth and initial mineralization of enamel created during amelogenesis.