• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.1
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• pp.95-105
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• 2001

The present study was designed to compare morphological and structural relationships between basicranial measurements such as MCF angulation (Ar-SE-ptm), saddle angle (N-S-Ba, N-S-Ar) and facial structures including types of malocclusion. Twenty six children with Class III whose longitudinal headfilms were available from 7 to 12-year-old, and also 26 cross-sectional headfilms at each ages of 8, 9, 10 and 11 with Class I were selected for the investigation. Cephalometric measurements such as Ar-SE-ptm, N-S-Ba, N-S-Ar, N-SE-Ar, SNA, SNB, N-S/PM vert, CP/PM vert, $\underline{1}/FH$ plane, and $N-perp/\underline{1}$ were measured. Morphologic relationships and pattern of changes in facial structures in relation to the changes of MCF and saddle angle in both malocclusion types were analysed statistically employing ANOVA, t-test and Pearson correlation. Results suggest that the MCF rather than the saddle angle in children with Class I and III is more closely related with various facial structures and with their changes. It may be, therefore, suggested that the MCF be one of the biologically meaningful measurements in determining structural relationships between cranial base and facial complex including types of malocclusion. In addition, the MCF and its correlated facial structures in children with Class III, interestingly, showed somewhat marked changes between the ages of 9 and 11.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.135-145
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• 2000

It is well known that there are different craniofacial skeletal groups in the same malocclusion types. The present study was performed to determine morphologic sub-groups in Korean children with Class III malocclusions, and to find out morphological differences between subgroups by means of a cross-sectional longitudinal cephalometric study. In this study, 135 children aged 6 to 14 year-old with untreated Class III malocclusions were selected. The samples were divided into two groups depending on the angulation of middle cranial fossa (MCF). That is, when the MCF of an individual was measured smaller than 40.3, he/she was tossed into mandibular protrusive-effect group(MREG), while when an individual was measured larger than 40.3, he/she was tossed into mandibular retrusive-effect group(MREG). Thereafter, the grouped samples were divided into 4 age groups(7, 9, 11 and 13 year-old). Thirty four linear and angular measurements on the tracings of lateral cephaloradiographs were measured, and the morphological characteristics and differences were compared and analysed by means of Wilcoxon test. It was found that Korean children with Class III malocclusions were divided into two groups, in which 39.3% were belonged in the MREG and 60.7% were in the MREG. In the MREG, anterior-posterior length of cranial base, nasomaxillary complex, maxilla and mandible were larger than the MREG. And although there was no difference in the total length of mandible (Co-Gn), mandibular body length (Go-Gn) was larger in the MREG during the majority of the observed periods. These results would suggest that a majority of the samples, 60.7%, demonstrated many of configurations of craniofacial skeletal relationships that can be found in the leptoprosopic faceform.