• The korean journal of orthodontics
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• v.29 no.4 s.75
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• pp.435-443
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• 1999

This study was undertaken to investigate the growth change of genial angle and interrelationship between the growth change of gonial angle and IMPA in the longitudinal data from 7 years to 15 years. By analyzing the serial lateral cephalograms or 15 males and 19 females of 7 years old to 15 yens old who had no abnomality in growth and development and no history of orthodontic treatment, the following conclusion were obtained. 1. Genial angle gradually decreased with aging in 25 children and in 9 children increased or maintained. 2. There was a tendency that children who decreased genial angle with aging showed gradual increase of IMPA and children who increased or maintained gonial angle with aging showed decrease of IMPA. 3. There was a tendency that regardless of the change of gonial angle, interincisal angle decreased with aging.

• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.247-261
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• 1995

The purpose of this study was to quantitate differences in the nature of the correction of Angle's Class II div 1 malocclusion dependent on the patient's age at the time of treatment. The sample consisted of 27 female patients in the adolescent group with a mean initial records age of 11.8 years and 25 female patients in the adult group with a mean starting age of 21.1 yrs. Lateral cephalometric head films were taken before and after orthodontic treatment with four bicuspid extraction. The results were obtained as follows. 1. None of maxillary skeletal parameters exhibited a significantly different in treatment change between adolescents and adults. But, in mandibular skeletal measurements, there were significant differences between two groups. (P<0.05) 2. Measures of vertical dimension in the adults remained unchanged during treatment, reflecting the effective absence of growth. 3. The steepness of occlusal plane in the adults changed significantly.(P<0.05) In contrast, the adolescents displayed stability of the occlusal plane. 4. According to the Johnston analysis, there was a significant difference in the total molar correction between two groups.(P<0.05) 5. According to the Johnston analysis, differential mandibular growth in the adolescents contrubuted $63\%$ of the total molar correction, with orthodontic tooth movement accounting for the remaining $37\%$. In the adults, dental movement comprised $99\%$ of the correction.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.3
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• pp.202-208
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• 2010

Purpose: This study was aimed to evaluate the effect of rhPMP-2 coated implants on alveolar ridge augmentation in dogs. Materials and methods: Six Beagle dogs were used in this study. Six 8.0 mm long anodized surface titanium implants were placed 5 mm into the mandibular alveolar ridge following 6 month of healing period after extraction. Each animal received three implants coated with rhBMP-2 and three uncoated control implants using the randomized split-mouth design. Radiographic examinations were undertaken immediately at implant placement (baseline), at weeks 4 and 8 after implant placement. The amount of bone augmentation was evaluated by measuring the distance from the uppermost point of the coverscrew to the marginal bone. Implant Stability Quotient (ISQ) values were measured immediately at implant placement and 8 weeks after implant placement. For the statistical analysis, Man-Whitney ranksum test and Wilcoxon signed rank test of SPSS 12.0 software were used (P=.05). Results: The BMP group exhibited radiographic vertical bone augmentation about $0.6{\pm}0.7$ mm at 8 weeks later while controls showed bone loss about $0.4{\pm}0.6$ mm. There was significant difference among the rhBMP-2 group and controls in bone level change (P<.05). The ISQ values were significantly higher in the BMP-2 group than the control group at 8 weeks later (P<.05), while there was no significant difference at surgery. Conclusion: Within the limitation of this study, the rhBMP-2 coated on anodized implant could stimulate vertical alveolar bone augmentation, which may increase implant stability significantly on completely healed alveolar ridge.

• Journal of the korean academy of Pediatric Dentistry
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• v.39 no.1
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• pp.90-96
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• 2012

Supernumerary tooth occurs most frequently at premaxilla area. Followed by mandibular premolar area, mandibular fourth molar area, maxillary paramolar area. Mesiodens are mainly impacted in the palatal area and surgical approach is made at palatal side. The time of surgery remains controversial. In case of inverted or horizontal impacted supernumerary tooth, intraosseous tooth movement and vertical growth of premaxilla makes surgical extraction more difficult. And also the more quantity of removed bone is, the higher degree of difficulty is. Inverted mesiodens of these cases were impacted superior to apex level of adjacent permanent incisor. Although CT examination revealed exact location of impacted tooth, surgical procedure including ostectomy may take a long time more than expected. So, before surgical extraction, it's need to be considered several factors such as necessity of CT taking, degree of difficulty, direction of surgical approach, necessity of general anesthesia etc.