Correlation of Left Mandibular Third Molar Development and Chronological Age / 대한소아치과학회지

The aim of this study is to evaluate the development of the left mandibular third-molar development with modified Demirjian method and its relation to chronological age.A total of 1653 digital panoramic radiographs of healthy individuals aged between 7 and 23 years who visited Yonsei University Dental hospital were selected. The developmental status of the left mandibular third molars was assessed using dental maturity scoring proposed by Demirjian et al. The mean age of the first appearance of mineralization, complete crown formation, and complete root formation were around 9, 14, 21 years respectively. Statistically significant differences between males and females in the development stage of D and G were revealed that crown formation and root length completion were attained earlier in males than in females. There was significant positive relationship between age and third molar development in both sexes, and new formula was presented to estimate age of children and adolescents based on their developmental stages of third molars.In this study, the use of left mandibular third molar as a developmental marker is appropriate, and age estimation can be attained with dental maturity stage.

Accuracy of Automatic Cephalometric Analysis Programs on Lateral Cephalograms ofPreadolescent Children / 대한소아치과학회지

The aim of this study was to evaluate the accuracy of 3 different automatic landmark identification programs on lateral cephalgrams and the clinical acceptability in pediatric dentistry.Sixty digital cephalometric radiographs of 7 to 12 years old healthy children were randomly selected. Fourteen landmarks were chosen for assessment and the mean of 3 measurements of each landmark by a single examiner was defined as the baseline landmarks. The mean difference between an automatically identified landmark and the baseline landmark was measured for each landmark on each image.The total mean difference of 3 automatic programs compared to the baseline landmarks were 2.53 ± 1.63 mm. Errors among 3 programs were not significantly different for 12 of 14 landmarks except Orbitale and Gonion. The automatic landmark identification programs showed significant higher mean detection errors than the manual method. The programs couldn’t be used as the 1st tool to replace human examiners. But considering short consuming time, these results indicate that all 3 programs have sufficient validity to be used in pediatric dental clinic.

Correlation between Dental and Skeletal Maturity in Korean Children / 대한소아치과학회지

The aim of this study was to investigate the relationships between the stages of calcification of various teeth and skeletal maturity stages among Korean subjects. The samples were derived from hand-wrist, panoramic radiographs, and lateral cephalograms of 743 subjects (359 males and 384 females) with ages ranging from 6 to 14 years. Calcification of seven permanent mandibular teeth on the left side were rated according to the system of Demirjian. To evaluate the stage of skeletal maturation, hand-wrist radiographs were analyzed by skeletal maturity indicators (SMI) system of Fishman and lateral cephalograms by cervical vertebral maturation (CVM) method of Baccetti. Statistically significant relationships were found between dental calcification and skeletal maturity stages according to Spearman rank-order correlation coefficients (r = 0.40-0.84, p < 0.001). The second molar showed the highest correlation and central incisor showed the lowest correlation for female and male subjects. For both sexes, canine stage G and second molar stage F were related to SMI 6 and CS 3. Because of the high correlation coefficients, this study suggests that tooth calcification stages from panoramic radiographs might be clinically useful as a maturity indicator of the pubertal growth period in Korean patients.

A Study on Visual Exploration of Children and Adolescents during Dental Treatment / 대한소아치과학회지

The aim of this study is to investigate visual exploration of children and adolescents during dental treatment by examining time ratio of eye opening in various age groups.This study reviewed 5 - 15 year-old patients who visited the department of pediatric dentistry of Yonsei University Dental Hospital from March to October 2018. Restorative treatment or sealant application was done by one pediatric dentist. A trained observer used 2 stopwatches to measure total treatment time and time of open eye. Average ratios of eye opening were calculated and compared.60 patients were investigated, with 15 patients in each age group. Average ratio of eye opening increased as age decreased (p This study indicated that children have higher rates of eye opening during dental treatment than adolescents.

Analysis of Primary Molar Relationship using Digital Photograph / 대한소아치과학회지

The aim of this study was to assess the occlusal relationships of primary dentition of Korean preschool children in Hwaseong city.Total 444 children of age group between 2 and 5 years were selected. One pediatric dentist took intraoral photos of children. Evaluation and categorization of the primary molar relationships were done by single examiner. Statistical analysis was performed with Pearson chi-squared test.Total 389 samples, which is consisted of 185 boys, 204 girls were satisfied with inclusion criteria. Bilateral mesial step was seen in 61.7%. Bilateral flush terminal plane was seen in 15.4%. When the primary molar relations of the right and left sides were not the same, the combination of the mesial step and flush terminal plane was 14.7%.The present study provides insight into occlusal relationships in the primary dentition of 2 - 5 years old of Korean children in Hwaseong city. Pediatric dentists should understand occlusal relationships of primary dentition for establishment of appropriate treatment strategies and occlusal guidance.

Evaluation of Characteristics of the Dental Maturity in Girls with Precocious Puberty / 대한소아치과학회지

Precocious puberty (PP) is defined as the early development of secondary sexual characteristics (before the ages of 8 years in girls and 9 years in boys). The aim of this study is to identify characteristics of the dental maturity in girls with PP that discriminate them from normal healthy girls. This study included 99 girls aged 6 - 8 years with PP and 99 girls without past medical history of same chronological age (control group). The study was performed on 198 panoramic radiographs (99 PP girls, 99 control group girls). Demirjian method was used to evaluate the panoramic radiographs and determine dental maturity. Difference in dental maturity score and tooth formation stages between the two groups were analyzed. The PP group showed significant higher maturity score than control group. Among mandibular teeth, mandibular 2nd premolar and 2nd molar were significantly more mature in the PP group than control group. Logistic regression analysis showed that mandibular 2nd molar was only significant predictor for PP girls.

Analysis of Treatment Period on the Intraoral Removable Appliance Utilizing Vertical Facial Growth on Class III Malocclusion / 대한소아치과학회지

Vertical facial growth triggers the rotation of mandible to move the chin point to the downward and backward direction, which showed remarkably effective result making the less prominent chin. Recently, the intraoral removable appliance utilizing class III elastic demonstrated the vertical growth trigger mechanism. The treatment change was very fast and wearing was quite easy, compared to extraoral appliances.The purpose of this study was to verify the duration of the treatment on class III malocclusion using intraoral removable appliances, which designed to accelerate vertical facial growth.56 patients were selected with the complaint of the protruded mandible and class III malocclusion (overjet : −3 – 0 mm, overbite : 0 – 4 mm). Information like; age at start, duration of the treatment events, type of the treatment, overjet, overbite etc. was collected and calculated.The average age of the patients delivering the initial brace was 8.75 ± 1.10 year. Most of the anterior crossbite was resolved within 6 months. The total treatment period was 21.79 ± 10.73 months with the additional procedures like the alignment of anterior teeth and torque control using additional removable and fixed orthodontic appliances. The correlation study showed that patient's cooperation (p = 0.000) and the use of fixed appliance (p = 0.032) were significantly influenced on treatment duration.

Dental Consultations and Treatment Pattern of Pediatric Inpatient in Severance Hospital / 대한소아치과학회지

The purpose of this study was to analyze the dental consultation of pediatric inpatients to the department of pediatric dentistry in Yonsei University Severance Hospital, and to investigate the change in patterns. In 2017, 268 pediatric patients (384 cases) admitted to the Severance Hospital were referred to the department of pediatric dentistry. The mean age was 6.6 years, and most of the patients were referred from the Department of Pediatric Hematology Oncology and Rehabilitation Medicine. The chief complaints were as follows: oral examination (31%), dental caries (20%), oral pain (10%), tooth mobility (10%), pre-operative evaluation (9%) and others (20%). 41% of the patients received only oral examination without treatment. Dental caries were the most frequent dental diagnosis of the patients. 28% (111 cases) of patients received operative treatments, 22 cases were treated under general anesthesia. Oral health is closely related to systemic diseases, especially for hospitalized patients. Dental consultations should be encouraged for prevention and early appropriate treatments. For this purpose, it is necessary to establish a referral system and perform dental treatment under general anesthesia.

Tooth Agenesis and Delay in Patients with Agenesis of Mandibular Second Premolars / 대한소아치과학회지

Tooth agenesis is a common human dental anomaly and the agenesis of mandibular second premolars has been proven to be the most frequently observed. The aim of this study is to investigate tooth agenesis and delayed tooth development in patients with agenesis of mandibular second premolars.This study reviewed 9 to 15 year-old patients with agenesis of mandibular second premolars who visited the department of pediatric dentistry of Yonsei University Dental Hospital and took panoramic radiographs from January 2014 to December 2016. On panoramic radiographs, agenesis of teeth was observed and developmental delay of teeth was evaluated by the Nolla method. Among 125 patients with agenesis of mandibular second premolars, 58 patients (46.4%) showed agenesis of other teeth and 38 patients (30.4%) showed delayed tooth development. In this study, patients with agenesis of mandibular second premolars were more likely to have tooth agenesis or delayed eruption of other teeth.

Comparison in Demineralization Resistance of Resin Infiltration and 1.23% Acidulated Phosphate Fluoride in Bovine Teeth / 대한소아치과학회지

The aim of this study is to compare the differences of the demineralization resistance of resin infiltration and 1.23% acidulated phosphate fluoride in bovine teeth with artificial caries. We applied 1.23% Acidulated phosphate fluoride (APF) gel and Icon® caries infiltrant on the artificial bovine enamel carious lesion and then demineralized all samples. The depth of demineralization was measured by using Confocal Laser Scanning Microscope (CLSM) and observed the roughness and irregularity of the enamel was observed by Scanning Electron Microscope (SEM).In this experiment with demineralization resistance on smooth artificial carious lesion, less depth of demineralization, roughness, and irregularity of enamel was observed in APF gel and Icon® group than in the control group. There was no significant difference between the depth of demineralization of 1.23% APF gel and Icon® caries infiltrant group. However, resin infiltration is beneficial as less roughness and irregularity was observed on the enamel surface than when 1.23% APF gel is applied.

The Changes of Sedation in the Department of Pediatric Dentistry, Yonsei University Dental Hospital / 대한소아치과학회지

Sedation is a useful behavior management technique for dental patients who may be uncontrollable or have medical problems. The aim of this study is to investigate the changes in patterns of sedative treatments in pediatric dentistry by analyzing the distribution of patients and used sedative agents.Patients and sedative agents were reviewed based on the electronic medical records (EMR) of the department of pediatric dentistry in Yonsei University Dental Hospital from 2011 to 2016.The number of patients who were treated under sedation generally increased. Male received more sedation treatment than female by 2014, and they became similar from 2015. The treatment percentage of patients with systemic disease decreased in 2013, remained constantly afterwards. The ratio of sedative treatment for the age 4 – 5 and age 6 – 10 generally increased, while that of the age 0 – 2 and older than age 11 decreased. The ratio of the age 3 remained steady. Nitrous oxide was the most frequently used sedative agent. The use of benzodiazepine increased while the use of chloral hydrate decreased.Although the use of sedation has expanded, multidimensional approaches for ensuring safety have been less focused. Therefore, it is necessary to explore further studies for the safety and efficacy of the use of sedation.

Correlation of Caries Experience and Activity between Mothers and Their Children Using a Colorimetric Test / 대한소아치과학회지

The purpose of this study was to compare the validity of Cariview®, a new colorimetric caries activity test, with CRT® bacteria, a conventional bacterial culture method. In addition, this study assesses the correlation between the dental caries experience and activity between mothers and their children.34 pairs of mothers and their children under the age of 6 years participated in this study with informed consent. After filling out a questionnaire and oral examination, the two caries activity tests above were performed on each subject.In the results, Cariview® scores were statistically significant with children's caries experience (r = 0.598, p <0.01) and showed higher correlation than CRT® bacteria scores. Cariview® scores showed statistically significant correlation with the number of decayed teeth in both mothers and children (p <0.05). In both Cariview® and CRT® bacteria tests, there was no statistically significant correlation between caries experience and caries activity (p > 0.05).Cariview® colorimetric test will be clinically useful for predicting future caries risk and establishing a preventative strategy in pediatric dentistry.

Comparative Proteomic Study of Spinal Cord after Applying Pulsed Radiofrequency to Dorsal Root Ganglion in the Rat

BACKGROUND: Pulsed radiofrequency treatment (pulsed RF) has recently been described as a non-neurodestructive or minimally neurodestructive alternative to radiofrequency heat lesions. However, there are few data to evaluate the mechanism of this therapy. The aim of this study is to explore the underlying mechanism of pulsed RF on spinal nervous system using comparative proteomic analysis. METHODS: L5 dorsal root ganglion was exposed to pulsed RF and sham treatment. Protein extracts from the spinal cord of both groups were analyzed using comparative proteomics to identify differentially expressed proteins. To validate the differential expression of proteins, we utilized western blotting and immunohistochemistry. RESULTS: The spinal cord taken from pulsed RF treated rats was found to underexpress 4-aminobutyrate aminotransferase, mitochondrial [Precursor]. Immunostaining density of gamma-aminobutyric acid measured from the spinal cord taken from pulsed RF treated rats was significantly increased compared with sham treated rats. CONCLUSIONS: We demonstrated that the decreased expression of 4-aminobutyrate aminotransferase, mitochondrial [Precursor] and increased expression of gamma-aminobutyric acid in the spinal cord after exposure of the lumbar dorsal root ganglion to pulsed RF. That might be the possible underlying mechanism of the analgesic effect of pulsed RF.

The Effect of Injection Direction during Hyperbaric Tetracaine Spinal Anesthesia with Pencil-Point Needle / 대한마취과학회지

BACKGROUND: Pencil-point needle currently are used for spinal anesthesia because of an alleged lowered incidence of postdural puncture headache. Although the direction of the side hole is one of the important factors that might affect the level and the duration of anesthesia, those data are not readily available. The aim of this study was to assess if the side hole direction of pencil-point needle during hyperbaric tetracaine injection affects the level and the duration of anesthesia. METHODS: We induced spinal anesthesia in 80 young men presenting for elective orthopedic surgery. Patients were allocated randomly with the side hole direction of the 25 gauge pencil-point needle in one of the four directions; cephalad, caudad, left lateral, right lateral. Hyperbaric 0.5% tetracaine 15~17 mg (3 to 3.4 ml) was injected with the speed of 0.75 ml/sec. Maximum sensory block level, time to maximum sensory block level, duration of sensory block (2 segments regression time) were assessed by a blinded observer with the pin-prick test and degree of motor block were measured by Bromage motor scale. Data were analysed using the Kruskal-Wallis test followed by the Mann-Whitney U test and chi-square test as appropriate (SAS v. 6.04). RESULTS: Time to maximum sensory block level was significantly fast in group 'cephalad'. Other values have no statistical differences. Post-spinal headache was observed in one case in group 'caudad'. CONCLUSIONS: Using the pencil-point needle, the time to maximum sensory block level was fast in group cephalad but there were no differences in the maximum sensory block level and the duration of sensory block among the four groups.

A case of esophageal perforation during endotracheal intubation in ankylosing cervical rheumatoid patient / 대한마취과학회지

Adverse respiratory events during endotracheal intubation for general anesthesia are variable. These events frequently occur to difficult airway patients. Traumatic endotracheal intubation with poor glottic exposure and blind thrust can perforate the hypopharynx or cervical esophagus. We experienced a case of esophageal perforation during endotracheal intubation for general anesthesia of total hip replacement in a 50 year old female patient. Neck extension was almost impossible due to longstanding ankylosing rheumatoid cervical arthritis. We tried several times of endotracheal intubation but failed. Post-operative esophago-graphy after we found subcutaneous emphysema confirmed esophageal perforation. Emergency tube drainage and general supportive care were done. Fortunately she recovered uneventfully and discharged on post-op. 30th days.