@article{oai:mdu.repo.nii.ac.jp:00000947,
 author = {山本, 昭夫 and 高橋, 順一郎 and 鈴木, 健雄 and 竹内, 博文 and 塚田, 洋 and 酒井, 基裕 and 澤田, 周介 and 笠原, 悦男 and 安田, 英一},
 issue = {3},
 journal = {松本歯学},
 month = {Dec},
 note = {application/pdf, Root ZX (ZX), a newly manufactured electric root canal length measuring device, has been recently introduced to the market. The manufacturer claims that it can accurately measure the root canal length in existence of electrolytes such as pulp tissue, blood or necrotic tissue in the root canal. This study was done in the clinic of Matsumoto Dental College to determine whether or not ZX had the properties claimed by the manufacturer, using Root Canal Meter (RCM) as control. The results obtained were as follows: 1. When the root canal length measured by a small size reamer (#25 or 30) was compared with that measured by a finally used reamer, in 12 of 20 pulpectomy cases (60.0%) the latter was 0.26±0.18mm longer than the former. On the other hand, in 9 of 13 infected root canal treatment cases (69.2%) at the root canal enlargement, the root canal length measured by a finally used reamer was 0.41±0.29mm longer than that measured by a small size reamer. 2. The differences between the root canal length remeasured at the time of root canal filling and that at the first appointment were examined. In 15 of 20 pulpectomy cases (75.0%), the root canal length of root canal filling was 0.67±0.78mm shorter than that measured at the first appointment. On the other hand, in 9 of 13 infected root canal treatment cases (69.2%), the root canal length at root canal filling was 0.52±0.37mm shorter than that measured at the first appointment. In either case, the root canal length of the first appointment tended to be shorter than that at root canal filling. 3. When a reamer tip was inserted into the root canal until the ZX meter pointed to 0.5 manufacture's the apical constriction reading according to the manual, the RCM reading was also examined. In the case of root canal enlargement, 10 pulpectomy cases (50.0%) and 5 infected root canal treatment cases (38.5%) indicated 40μA or greater of RCM. At the time of root canal filling, 8 pulpectomy cases (40.0%) and 7 infected root canal treatment cases (53.8%) were 40μA or greater. In approximately half of the cases, it was recognized that the reamer tips overextended beyond the apical foramen. 4. The location of the tip of gutta-percha point was examined using a dental X-ray taken immediately after root canal filling was performed. In 11 pulpectomy cases (61.1%) and 5 infected root canal treatment cases (41.7%), the master corn tips extruded from the radiographic root apex. 5. It may be concluded that ZX can measure the root canal length in existence of electrolytes but is somewhat affected by electrolytes.},
 pages = {235--244},
 title = {改良型電気的根管長測定器の測定精度について},
 volume = {19},
 year = {1993}
}