• Journal of Mushroom
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• v.2 no.2
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• pp.88-96
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• 2004

This study was executed to decide the physiological characteristics of Ferule mushroom. Four strains of Ferule mushroom were tested to select a superior strain in its mycelial growth. The pertinent substrates, temperature and pH ranges for the growth of selected strain were determined. And then, the wood rotting ability and type of the Ferule mushroom were determined. The superior strain F-2 among four strains was selected, on the basis of its vegetative mycelial growth and density on agar media. Mycelial growth of F-2 was the best on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about $25{\sim}34^{\circ}C$ and best at $30^{\circ}C$. The optimum pH range on MYPA was 5.0~6.0. The mycelial growth was mostly stimulated by soluble starch at cont. 1% (w/w) and secondly, maltose among several carabon sources and by mixed solution of YE(0.25%) and ME(0.25%) but not by ME alone. Cell thining and erosion of Pinus rigida wood by the mycelia of Ferule mushroom were found only on a few cell but largely at wood block test, indicating that the softwood rotting ability of Ferule mushroom mycelia was not so good. The result of polarized light microscopy appeared that cellulose of some tracheides showing the S3 layer lost brifringence was degraded by Ferule mushroom. But only part of cellulose of P. rigida wood was degraded by Ferule mushroom, because most of wood cells continued to showing briefingence. A largely degraded ray parenchyma and longitudinal parenchyma cell and partly thinning and erosion of hardwood(Quercus serrata) cell was found and it indicates that the rotting ability of Ferule mushroom mycelia on hardwood was higher than on softwood. It could be concluded that the difference in the wood rot by Ferule mushroom between the hardwood and softwood was made by the difference of chemical constitutions between them, especially in the contents and the types of lignin. Ferule mushroom was considered as white rotter as a result of bavendam test, although more research should be required.

• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.469-485
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• 1996

Orthodontic patients are individuals that grow and develop ; therefore selection of the proper time for orthodontic treatment is considered to be one of most difficult and yet difficult factor. Since the development of cephalometric X-ray, amount and Pattern of craniofacial growth change with aging could be predicted and be came useful in the process of orthodontic treatment. The relationship between the mean values of cephalometric measurements and body height and weight was studied among the groups(boys and girls) of Korean children from the ages 6-years to 17-years. 409 boys and 437 girls with no abnormality in growth and development and no history of orthodontic treatment from the ages of 6 years to 17 years were chosen as subjects Cephaloment X-ray were taken for 3 years and hard tissue analysis based on Burstone's COGS, which was devided into measurements of 6 parts(Cranial base, Maxillar and Mandible, Dental measurements). The relationship between craniofacial growth and height & weight was studied. The following conclusions were obtained : 1. The maximum growth in the measurements of cranial base, N-Ar(FH), N-Ba(FH) corresponded with the age with the maximum increase in body height & weight in both boys and girls. 2. Genial angle gradually decreased with aging in both boys and girls. 3. N-ANS(L) showed greater amount of growth than ANS-Ne(L), and this had greater influence on facial profile. 4. N-A-$Pog^{\circ}$ decreased with aging, and mandibular growth exceeded maxillary growth in amount and rate. 5. Length of Y-axis Increased, but Y-axis to FH plane remained constant. This show that mandible grows at a constant angulation to cranial base. 6. As permanent teeth erupt, interincisal angle deceased.

• Restorative Dentistry and Endodontics
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• v.32 no.1
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• pp.37-46
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• 2007

The C-shaped canal system is an anatomical variation mostly seen in mandibular second molars, although it can also occur in maxillary and other mandibular molars. The main anatomical feature of C-shaped canals is the presence of fins or web connecting the individual root canals. The complexity of C-shaped canals prevents these canals from being cleaned, shaped, and obturated effectively during root canal therapy, and sometimes it leads to an iatrogenic perforation from the extravagant preparation. The purpose of this study was to provide further knowledge of the anatomical configuration and the minimal thickness of dentinal wall according to the level of the root. Thirty extracted mandibular second molars with fused roots and longitudinal grooves on lingual or buccal surface of the root were collected from a native Korean population. The photo images and radiographs from buccal, lingual, apical direction were taken. After access cavity was prepared, teeth were placed in 5.25% sodium hypochlorite solution for 2 hours to dissolve the organic tissue of the root surface and from the root canal system. After bench dried and all the teeth were embedded in a self-curing resin. Each block was sectioned using a microtome (Accutom-50, Struers, Denmark) at interval of 1 mm. The sectioned surface photograph was taken using a digital camera (Coolpix 995, Nikon, Japan) connected to the microscope. 197 images were evaluated for canal configurations and the minimal thickness of dentinal wall between canal and external wall using 'Root Thickness Gauge Program' designed with Visual Basic. The results were as follows : 1. At the orifice level of all teeth, the most frequent observed configuration was Melton's Type C I (73%), however the patterns were changed to type C II and C III when the sections were observed at the apical third. On the other hand, the type C III was observed at the orifice level of only 2 teeth but this type could be seen at apical region of the rest of the teeth. 2. The C-shaped canal showed continuous and semi-colon shape at the orifice level, but at the apical portion of the canal there was high possibility of having 2 or 3 canals 3. Lingual wall was thinner than buccal wall at coronal, middle, apical thirds of root but there was no statistical differences.