There was a great problem about the deposition between materials of a different kind at the beginnings of the introduction of porcelains, however, thereafter the deposition efficiency was settlded to the sufficient level of all user thanks to effort to have studied by many scholars and clinical authorities. But in a clinical process, as the difference of designs has an effect on fractures of porcelains, this researcher divided them into 4 groups of A: 1 mm, B: 2 mm, C: 3 mm, and D: 4 mm, and made 40 pieces to each 10 as the test samples to consider a length axis of tooth for studies in accordance with a position of a finishing line to meet between porcelain and metal at the contact point at the adjacent side to a metal porcelain. The sample materials are those to be use at the open market and the test samples wer completed by the same manufacturing technique to that of existent metal porcelain tube. s a result of the strength test on fractures, the average value is as in the following, A: 1 mm - 8.5bar, B: 2 mm - 10.5bar, C: 3 mm - 14.3bar, and D: 4 mm - 15.0bar. In case of the metal porcelain tube, the more faraway to process parts of metal and porcelain from the contact point of adjacent side has the stronger strength of fractures, Accordingly, the research shows that it had better to keep off more than 3 to consider a ledngth axis of tooth.