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한국인의 상악 제1대구치 근심 협측 치근의 근관형태에 관한 연구
민경산,김용관 關東大學校 醫科大學 醫科學硏究所 2003 關東醫大學術誌 Vol.7 No.1
The purpose of this study was to determine the percentage of anatomical canal configurations of the mesiobuccal root of the maxillary first molar in Korean patients. One hundred and fifty extracted maxillary first molar was used in this study. The distobuccal and palatal roots were amputated for radiographic convenience. Preoperative radiographs were taken of the remaining crown and mesiobuccal root from mesiodistal and buccopalatal directions for each tooth. Endodontic access cavities were prepared and size 15 K file were placed to the apexes. postoperative radiographs with files in place were taken from the two directions, as before. Of the 150 teeth,58 (38.7%) were TypeⅠ,47 (31.3%) were Type Ⅱ,42 (28.7%) were Type Ⅲ, 2 (1.3%) were Type Ⅳ. It is concluded that two canals in mesiobuccal roots of maxillary first molars of Korean is a common occurrence and the proportion of cases was high and similar to that described from studies of other ethnic populations.
측방가압충전시 Nickel-Titanium spreader의 사용유무가 근관충전효과에 미치는 영향
민경산,홍찬의,조용범 대한치과보존학회 2000 Restorative Dentistry & Endodontics Vol.25 No.3
Lateral condensation with gutta-percha and sealer has been shown to provide an excellent apical seal: however, the lateral condensation technique has demonstrated less favorable apical leakage results in curved canals when compared with straight canals. Placement of endodontic spreaders to within 1 to 2mm of the root canal working length has been advocated for Optimum gutta-percha obduration. Due to their stiffness, stainless-steel(SS) spreaders will often fail to achieve this position in curved canals. Newly marketed nickel-titanium (NT) spreaders may offer an advantage in this regard due to the increased flexibility of these instruments. The purpose of this study was to evaluate the effect of NT finger spreader on the sealing ability in lateral condensation technique, compared with conventional SS finger spreader. Twenty four standardized resin models simulating curved canals(30 degree) were groups and instrumented to a #30 master apical ale size with Ni-Ti Profile .04 taper series using step down technique. Each groups was obdurated with pique using SS finger spreader, NT finger spreader. And then, each model was sectioned horizontally with microtome at 1, 2, 3, 4, smm levels from the apex. At each of 5 levels, ratio of the area of gutta-percha was obtained by calculating the area of Ntta-percha to the total area of the canal. The data collected were then analyzed statistically using a t test for indepent samples. The results as follows: 1.The total mean ratio of area of gutta-percha was 89.20±7.00(%) for SS sprender group. 99.20±5.17(%) for NT spreader group.There was statistically significant difference between each group(p〈0.05). 2.At 3mm level, the mean ratio of area of Ntta-percha was 88.32±5.41(%) for SS spreader group, 95.25±2.60(%) for NT spreader group. There was statistically significant difference between each group(p〈0.05) . At 1,2,4mm levels, NT spreader group showed greater mean ratio of area of gutta-percha than SS spreader group, too. But there was no statistically significant difference. 3.At 5mm level, the mean ratio of area of Ntta-percha was 91.83±3.42(%) for SS spreader group. 87.91±3.68(%) for NT spreader group. There was statistically significant difference between each group(p〈0.05). This study concluded that the NT spreader demonstrated somewhat favorable apical sealing efffct than 55 spreader in prepared curved canals. The clinical use of NT spreaders may enhance our ability to create better apical seals in curved canals, but further studies in this area will help clarify some of fhe remainingareas with which practitioners are concerned, such as compaction forces exerted by NT spreaders.