Surface roughness and surface free energy components of various orthodontic adhesives / 대한치과교정학회지

OBJECTIVE: Surface characteristics of dental materials play an important role in bacterial adhesion. The purpose of this study was to investigate surface characteristics of 5 different light-cured orthodontic adhesives (1 fluoride-releasing composite, 3 non-fluoride-releasing composites, and 1 resin-modified glass ionomer). METHODS: Surface roughness was measured using a confocal laser scanning microscope. Contact angle and surface free energy components were analyzed using the sessile drop method. RESULTS: Surface roughness was significantly different between adhesives despite a relatively small variation (less than 0.05 micrometer). Lightbond and Monolok2 were rougher than Enlight and Transbond XT. There were also significant differences in contact angles and surface free energy components between adhesives. In particular, considerable differences in contact angles and surface free energy components were found between resin modified glass ionomer and the composites. Resin modified glass ionomer showed significantly smaller contact angles in 3 different probe liquids and had higher total surface free energy and stronger polarity, with notably stronger basic property than the composites. CONCLUSION: Resin modified glass ionomer may provide a more favourable environment for bacterial adhesion than composite adhesives.

Spacing and crowding of the primary dentition in Korean children - relationship to tooth sizes and dental arch dimension / 대한치과교정학회지

The aims of this study were to investigate the prevalence of spaced, closed, and crowded primary dentitions by sex and arch in Korean children from Kanghwa, and to determine the frequency of the primate and developmental spaces. The differences in the mesiodistal crown diameters and the arch dimensions between the spaced, closed, and crowded primary dentitions were also evaluated. Dental casts of 102 preschool children (57 males and 45 females, aged 4 ~ 5 years) were studied. The prevalence of spacing in the primary dentition was 63.2% in males and 57.8% in females. The frequency of spacing was greater in males than in females, and greater in the maxillary arch than in the mandibular arch. The crowns were significantly larger and the arches significantly narrower in closed and crowded dentitions than in those with spacing (p < 0.05). The results showed that the prevalence of spacing was lower than that found in previous studies and the presence of spacing in the anterior region was related to the mesiodistal crown diameter and the intercanine width.

Soft tissue changes after double jaw rotation surgery in skeletal class III malocclusion

The aim of this study was to evaluate the amount and interrelationship of the soft and hard tissue changes after simultaneous maxillary clockwise rotation and mandibular setback surgery in skeletal class III malocclusion. The sample comprised of 16 adult patients who had anteroposterior skeletal discrepancy. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of Le fort I Osteotomy and bilateral saggital split ramus osteotomy. The presurgical (T1) and postsurgical (T2) lateral cephalograms were evaluated. The computerized statistical analysis was carried out with SPSS/PC program. The results demonstrated a decrease in the vertical dimension in the soft and hard tissue. The nasolabial angle was increased and the mentolabial angle was decreased. The results showed also many statistically significant correlations(p<0.05). The lower lip closely followed the skeletal movement of the B- point in the horizontal plane. The double jaw rotation surgery can afford a good solution to solve the problems of class III malocclusion cases.

The change of expression of interleukin-6 and -8 after the application of the static compressive pressure on the fibroblast originated from the periodontal ligaments

The fibroblast in the periodontal ligaments received various stress. Among them, compression and tension are quite important and they are related to the remodeling of tooth and alveolar bone. We studied the change of expression of interleukin-6 (IL-6) and interleukin-8 (IL-8) in the fibroblasts of the periodontal ligaments by real-time RT-PCR and ELISA. In results, the relative activity of IL-6 mRNA in 2 hours after was 1.54+/-0.08 and 1.00+/-0.05 in control and test, respectively (P<0.05). Its 12 hours after was 1.23+/-0.06 and 2.78+/-0.14 in control and test, respectively (P<0.05). The relative activity of IL-8 mRNA in 2 hours after was 1.00+/-0.05 and 0.24+/-0.01 in control and test, respectively (P<0.05). Its 12 hours after was 1.23+/-0.06 and 0.63+/-0.03 in control and test, respectively (P<0.05). The concentration of IL-6 was 1.02+/-0.16 ng/ml, 0.90+/-0.14 ng/ml, and 1.32+/-0.12 ng/ml (P<0.05) in control, 2, and 12 hours after, respectively. The concentration of IL-8 was 2.26+/-0.17 ng/ml, 1.70+/-0.26 ng/ml (P<0.05), and 0.84+/-0.47 ng/ml (P<0.05) in control, 2, and 12 hours after, respectively. In conclusion, the expression of IL-6 was significantly increased after the application of the static compressive force, but IL-8 was significantly decreased. Considering their known function, their expression is quite important in tooth and bone resorption.

The expression of FGF-5 and FGF-7 in the cyclosporin a-induced gingival hyperplasia

Cyclosporin A-induced gingival hyperplasia is frequently found in the patients who have been received an immunosuppressant for the organ transplantation. However, its exact mechanism is still unknown. The expression of FGF-5 and FGF-7 were studied in cyclosporine A-induced gingival hyperplasia (CGH) and inflammatory gingival hyperplasia (IGH). Immunohistochemistry and in situ hybridization were used for localization of protein and mRNA. The expression of FGF-5 and FGF-7 was different from CGH and IGH. FGF-5 and FGF-7 was strongly expressed in fibroblast in CGH (P<0.005 and P<0.05, respectively). FGF-5 mRNA was localized in the middle portion of connective tissue. FGF-7 mRNA was also identified in fibroblasts and mast cells. In conclusion, FGF-5 and FGF-7 were produced excessively by fibroblasts in CGH. Considering their known functions, their expression in CGH is important for production of collagen and proliferation of fibroblasts.

Gene expression after the application of the fluid-induced shear stress on the gingival fibroblast

0.7). The "RUNX-1" was increased its expression in 2 hours group and "RUN and SH3 domain containing 1" was increased its expression in 4 hours group. The "CC020415", "cyclin L1", "interferon regulatory factor1", "early growth response 1", "immediate early response 2", and "immediate early response 3" genes were increased their expression in 2 and 4 hours after FISS application. In conclusion, we could find many genes that were probably related to the FISS application. Interestingly, most of them were placed in similar molecular pathways and these findings improve the reliability of chip data and usefulness in overall screening. From this experiment, we could find many items for further study and it will make improvement in the understanding of intracellular events in response to FISS.

The shear stress proteome of chondrocytes

Direct detection of cariogenic streptococci in metal brackets in vivo using polymerase chain reaction / 대한치과교정학회지

Streptococcus mutans and Streptococcus sobrinus are major etiological agents in enamel demineralization around orthodontic appliances. This study was designed to examine the prevalence of these streptococci on orthodontic brackets in vivo using polymerase chain reaction. Four incisor brackets in the upper and lower arches were removed and collected from 80 patients at the time of debonding. The genomic DNA of adhered bacteria was extracted and each dextranase gene of S. mutans and S. sobrinus was amplified using the specific oligonucleotide primers. The results showed that the maxillary incisor brackets were colonized by both cariogenic streptococci to a somewhat higher degree than that taken from the mandible. The prevalence of S. mutans was 50.0% on the maxillary incisor brackets and 33.8% on the mandibular incisor brackets, and that of S. sobrinus was 17.5% and 15.0%, respectively. Both species were detected on the maxillary incisor brackets of 7 patients (8.8%) and the mandibular incisor brackets of 5 patients (6.3%). These results suggest that cariogenic streptococci can adhere to the incisor brackets and may be resident species on the incisor brackets.

A study on the anterior tooth size discrepancies among orthodontic patients with varying malocclusions / 대한치과교정학회지

Bolton analysis is widely used to predict tooth size discrepancy, but its accuracy has been challenged. The purpose of this study was to describe true anterior tooth size discrepancies among orthodontic patients and to evaluate the factors that affect true anterior tooth size discrepancies. The subjects consisted of 80 patients with varying malocclusions (Class I, Class II, Class III, and Class III surgery) who were treated orthodontically. Pre-treatment models, set-up models from post-treatment models, and lateral cephalometric radiographs were analyzed. The results were as follows. The means, the standard deviations, and ranges of anterior Bolton ratio in the present study were somewhat higher than those of Bolton's samples and Korean normal samples. The number of patients showing maxillary deficiency was larger than that of patients showing maxillary excess in view of true anterior discrepancies. There was a significant difference between anterior Bolton discrepancy from pre-treatment models and true anterior discrepancy from set-up models (p 0.05). And there was also no significant difference between the male and female groups (p > 0.05). Overbite and the incisal edge thickness of maxillary anterior teeth have little relationship with true anterior discrepancies. Multiple regression analysis showed that true anterior discrepancy was mainly determined by anterior Bolton ratio, upper incisor to occlusal plane angle after treatment, interincisal angle after treatment, and upper right lateral incisor width.

THE DIFFERENCE IN THE PREVALENCE OF THE IVS5-A/G OF THE TRANSFORMING GROWTH FACTOR-BETA3 GENE BETWEEN KOREANS AND ROMANIANS

Tooth size and arch parameters of normal occlusion in a large Korean sample / 대한치과교정학회지

The aim of this study was to establish normative data on the tooth size and arch parameters of Koreans with normal occlusion. This study employed the dental casts of 296 (male: 179; female 117) normal occlusion samples, who were selected from 15,836 adults through a community dental health survey. The mesiodistal diameters of teeth, arch width, and arch length were measured by digital electronic calipers (accurate to 0.01 mm) and Bolton's indices as well as intermaxillary arch width ratios were calculated. In order to ensure reliability, intra- and inter-examiner error were evaluated. Although our dimensional data showed overt differences between genders, the indices and intermaxillary ratios evaluated were the same. The resultant data obtained were compared with the previous data to reveal whether any changes have occurred over the time. The clinical implication of the present findings was also discussed. This biometric study seemed to provide a clinically applicable diagnostic criteria for an individual malocclusion patient.

The ethnic difference of the prevalence of SfaN polymorphism in the nonsyndromic cleft palate / 대한치과교정학회지

Nonsyndromic cleft lip and/or palate (NSCLP) is one of the most common congenital deformities and its prevalence in Far East Asia, such as within Korean and Japanese populations, is relatively high. However, in the eastern part of Europe, clefts are relatively rare situations. These ethnic differences infer a genetic background of the disease. The objective of this study was to compare the frequency of single nucleotide polymorphism (SNP) in TGF-beta3 between Korean and Romanian cleft families. Korean cleft families samples were collected from twenty-six families (n=78) and Romanian cleft families samples were collected from eighteen families (n=41). For sequencing, the blood or saliva of the subjects was sampled. A single nucleotide plolymorphism was observed in the intron 5 of TGF-beta3 (A18141G). The frequency of each allele was significantly different between the Korean and Romanian samples. The AA allele was present in 18 out of 78 Korean samples (23.1%) and in 27 out of 41 Romanian samples (65.9%). The AG was present in 27 (34.6%) out of 78 Koreans and in 13 (31.7%) out of 41 Romanians. The GG was found in 33 (42.3%) Koreans and in 1 (2.4%) Romanian. The difference between the groups was significant (p<0.001). In conclusion, the frequency of observed SNP was significantly different between the two countries. SNP in TGF-beta3 in the Korean population seemed to have a higher possibility of occurrence for nonsyndromic cleft palate than the Romanian population

Analysis of dentoalveolar compensation and discrimination of skeletal types / 대한치과교정학회지

The purpose of this study is to analyze dentoalveolar compensation in normal occlusion samples previously classified into 9 skeletal types, and to provide clinically applicable diagnostic criteria for individual malocclusion patients. Cephalometric measurements of the 294 normal occlusion samples previously divided into 9 types were analyzed. The descriptive features of dentoalveolar variables were compared for the 9 types using analysis of variance, followed by post hoc multiple comparisons. In addition, the correlation between skeletal and dentoalveolar variables were analyzed. Discriminant analysis with a stepwise entry of variables was designed to find out several potential variables for use in skeletal typing. The dentoalveolar compensation pattern of the skeletal types varied, especially with regards to the variables that indicated the inclination of incisors and the occlusal plane. Stepwise variable selection identified four variables: AB- MP, SN-AB, PMA and ANB. Discriminant analysis assigned a classification accuracy of 87.8% to the predictive model. On the basis of these results, this study could provide rudimentary information for the development of diagnostic criteria and treatment guidelines for individual skeletal types.

Classification of the skeletal variation in the normal occlusion / 대한치과교정학회지

The purposes of this study were to classify the anteroposterior and vertical skeletal pattern of normal occlusion samples into specific types with factor and hierarchical cluster analysis, and to evaluate the range and limit of skeletal relationships that permit the establishment of normal occlusion via natural dentoalveolar compensation. Lateral cephalograms of 294 normal occlusion samples were measured, as selected from 15,836 persons through a community dental health survey who cooperated in record taking. Using a factor analysis, two factors representing anteroposterior and vertical skeletal relationships were extracted from 18 skeletal measurements. Then cluster analysis classified the skeletal patterns into nine types. The means and the standard deviations of 8 anteroposterior skeletal measurements and 10 vertical skeletal measurements were determined and comparisons of these measurements among the types were performed. The results obtained in this study showed that the range of normal occlusion included very diverse anteroposterior and vertical skeletal relationships.

A study on the relationship between jaw size and tooth size / 대한치과교정학회지

The purpose of this study was to find whether there is a correlation between tooth size and jaw size. Dental stone models and cephalometric radiographic films of 87 untreated individuals were evaluated. Repeated measurements of the maximum mesiodistal width of the teeth were taken by means of a digital vernier caliper. Linear measurements of jaw size were assessed by means of a digitizer and Visual C++ program. All measurements were taken separately according to the subject's gender. To determine the relationship between jaw and tooth size, the Pearson correlation was used. The results were as follows: 1. Male and female subjects showed a statistical difference in regard to tooth size and jaw size 2. In contrast to the results of the male subjects, there were no statistically significant correlations between maxillary size and maxillary teeth size in female subjects 3. In male subjects, the two maxillary sizes of PTM vert-ANS vert (FH plane) and PTM vert-A vert (palatal plane) were significantly correlated with themaxillary teeth size. Especially, the size of the upper central incisor showed significant correlation with all maxillary sizes. 4. In both male and female subjects, mandibular size B vert- Point J vert (mandibular plane) showed significant correlation with mandibular teeth size. As gleaned from the results of this study, the relationship between jaw size and tooth size was fair or little in natural occurring good occlusion.

Effects of chewable tablet containing sodium fluoride and xylitol on the oral hygiene state in the orthodontic patients / 대한치과교정학회지

The aim of this study was to evaluate the effect a chewable tablet containing sodium fluoride and xylitol (DenPo, Hamizzle, Bucheon, Kyungki) on the oral hygiene state in the orthodontic patients. The subjects consisted of 30 adult orthodontic patients, who have worn the fixed orthodontic appliance at least 6 months. They were instructed to use the tablet forth a day. Gingival index (GI), plaque index (PI), and sulcus bleeding index (SBI) of upper and lower anterior and posterior regions were measured before using the tablet (T0), 2 weeks after using the tablet (T1), and 4 weeks after using the tablet (T2). The data were analyzed with Wilcoxon signed ranks tests. The results were as follows ; 1. PI was decreased significantly in the T1 and T2 stage compared with T0 stage in the both anterior and posterior regions (p 0.05). 2. GI and SBI showed similar results compared with PI. In the T1 and T2 stage, there was statistically significant decrease in the GI and SBI (p < 0.05). This study showed that the DenPo tablet could be used as an adjunct to improve oral hygiene in the orthodontic patients. The decrease of the indices may suggest that DenPo tablet could be effective in the plaque removal and prevention of gingival inflammation in the orthodontic patients.

Current trends in orthodontic patients in Seoul National University Dental Hospital / 대한치과교정학회지

Over the past decades, the number of patients seeking orthodontic treatment has increased markedly with socioeconomic development and change of recognition on appearance. The purpose of this study was to provide an epidemiologic data base related to the orthodontic treatment need. We could take an adequate information regarding the characteristics of orthodontic patients, and the changing trends about treatment mordality. Distrubution and treands were investigated in 676 patients who had been examined and diagnosed at Department of orthodontics, Dental Hosital, Seoul National University from January to June in 1992 and 2002. 1. Sex distribution of patients changed from 1 : 2.1 to 1 : 1.5 (male : female). 2. In 2002, age distribution had shown 7~12 year-old group being the largest (32.0%) and percentage of 19~24, 13~18, over 25, 4~6, 0~3 year-old group were 24.0%, 21.6%, 14.2%, 5.8%, 2.4% respctively. Compared with data in 1992, the number of adult patients highly increased. 3. With regard to Angle classification, each percentage of Class I , Class II div 1, Class II div 2, and Class III malocclusion were 25.0%, 20.9%, 3.4%, and 48.1% respectively in 2002. 4. Geographic distribution showed that most of the patients visited (37.0%) lived in northeast of Seoul in 2002. 5. Mandibular prognathism showed the highest percentage in chief complaints. The percentages of crowding and facial asymmetry were 14.2% and 11.8% in 2002. Patients with facial asymmetry increased significantly. 6. Percentages of patients treated with fixed appliance and orthognathic surgery were 38.0% and 25.0% in 2002. Patients needed to observe the growth pattern comprised 13.0% with increasing trends. The use of chin cap reduced and the percentage of orthognathic surgery and growth observation increased significantly.

Locus of control of surgical-orthodontic patient / 대한치과교정학회지

Surgical-orthodontic treatment is an increasingly more common dental procedure whose unique psycho-social or psychological feature has not been fairly quantified objectively. Since the treatment of a surgical-orthodontic (or orthodontic) patient is part science and part art, a subjective recognition of a patient about his or her own treatment may be more important than technical success during and after treatment. Therefore, the knowledge of the patient's underlying psychological status could be useful in the prediction of patient's response to surgical-orthodontic (or orthodontic) treatment. The purpose of this study was to investigate and evaluate the psychological difference between conventional orthodontic patient and surgical-orthodontic patient by using locus of control (LOC) examination. Locus of control scale has been proven to be extremely useful in the prediction of a variety of human behaviors. Two types of locus of control data (I-score, Internal locus of control score; E-score, External locus of control score) were obtained for 42 surgical-orthodontic patients and randomly selected 42 conventional orthodontic patients (as a control group) matched for age and gender. No statistically significant difference was observed in the scale of internal and external locus of control between the groups of surgical-orthodontic patients and conventional orthodontic patients. However, in the group of surgical-orthodontic patients, males showed lower E-score (external locus of control score, higher internal locus of control tendency) than females. The results of this study suggested that the psychological background of surgical-orthodontic patients, in contrast with that of cosmetic surgery patients, has a similar disposition with that of orthodontic patients.

Soft tissue cephalometric analysis of aesthetic Korean female / 대한치과교정학회지

The purpose of this study was to provide data on the normative values of some clinically important soft tissue dimensions for adult Korean females with aesthetically beautiful facial profiles. Lateral cephalograms of 18 Korean female models, who were selected for their well balanced and aesthetic facial profiles, were evaluated. All cephalograms were taken with the subjects in a natural head position with the teeth in occlusion and the lips at rest. The means and standard deviations were determined and presented. In addition, comparisons with the previous studies were performed. The results of the present study were as follows: 1. The upper and lower lips were posteriorly located in relation to the Ricketts' E line (Upper lip to E line: -2.08, Lower lip to E line: -0.04). 2. Both lips were more posteriorly located than those in the results of previous studies on Korean females selected by normal occlusion, but more anteriorly located than in the results of studies selected on an aesthetic basis. 3. The nasolabial angle for this sample was 101.03 degrees with a standard deviation of 8.47 degrees.

Adherence of salivary proteins to various orthodontic brackets / 대한치과교정학회지

The principal aims of this study were to identify the composition of salivary pellicles formed on various orthodontic brackets and to obtain a detailed information about the protein adsorption profiles from whole whole saliva and two major glandular salivas. Four different types of orthodontic brackets were used. All were upper bicuspid brackets with a 022 x 028 slot Roth prescription; stainless steel metal, monocrystalline sapphire, polycrystalline alumina, and plastic brackets. Bracket pellicles were formed by the incubation of orthodontic brackets with whole saliva, submandibular-sublingual saliva, and parotid saliva for 2 hours. The bracket pellicles were extracted and confirmed by employing sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western transfer methods, and immunodetection. The results showed that low-molecular weight salivary mucin, alpha-amylase, secretory IgA (sIgA), acidic proline-rich proteins, and cystatins were attached to all of these brackets regardless of the bracket types. High-molecular weight mucin, which promotes the adhesion of Streptococcus mutans, did not adhere to any orthodontic brackets. Though the same components were detected in all bracket pellicles, however, the gel profiles showed qualitatively and quantitatively different pellicles, according to the origins of saliva and the bracket types. In particular, the binding of sIgA was more prominent in the pellicles from parotid saliva and the binding of cystatins was prominent in the pellicles from the form plastic brackets. This study indicates that numerous salivary proteins adhere to the orthodontic brackets and these salivary proteins adhere selectively according to bracket types and the types of the saliva.