1[1]Ortman LF,McHenry K,Haussman E. Relationship between aleolar bone measured by 125I absorptiometry with analysis of standard radiographs:2 Bjorn technique. J Periodontol,1982,53:311～314．
2[2]Gr6ndahl H-G, Gr6ndahl K, Webber RL. Subtraction radiogrphy for the dignosis of periodontal bone lesions. Oral Surg ,1983,55:208～213．
3[3]Ortman LF, Dunford R, McHenry K et al. Subtraction radiography and computer assisted densitometric analysis of standardized radiographs. A comparison study with '25I absorptiometry. J Periodont Res， 1985,20:644～651．
4[4]Vandre RH, Webber RL. Future trends in dental radiology. Oral Surg Oral Med Oral Pathol Oral RadiolEnded， 1995 Oct; X0(4):471～478
5[5]Brgger U, Biir g n W Marconi M et al. Influence of contrast enhencement and pseudocolor transformation on the diagnosis with digital subtraction images(DSI). J Periodont Res,1994;29:95～102．
7[7]Mistak EJ, Loushine RJ, Primack PD et al. Interpretation of periapical lesions comparing conventional, direct digital, and telephonically transmitted radiographic images. J Ended， 1998;24(4):262～266．
8[8]Brgger U,Pasquali L,Kornman. Remodelling of interdental alveolar bone after periodotal flap procedures assessed by means of computer-assisted densitometric image analysis(CADIA). J clin periodontol， 1988;15:558～564．
9[9]Jeffcoat MS,Webber RL,Williams RC et al. Extracoronal central of geometry for digital subtraction radiography. J Periodont Res,1987;22:396～402．
10[10]Eickholz P,Benn DK,Staehle HJ.Radiographic evaluation of bone regeneration following periodontal surgery with or without expended po lytetraflu oro ethyl ene barriers. J Periedontol,1996;67:379～385．
5Melcher AH. On the repair potential d periodontal tissue[J]. J Perlodontal, 1976,47(5) :256 - 260.
6Lekovic V, Camargo PM, Weinlaender M,et al.A comparison between enamal matrix proteins used alone or in combination with bovine porous bone mineral in treatment d inky perindoatal ddects in hunN~[J] .J peridontol,2000,71 (7) : 1110 - 1116.
7Blume H, Jost RG Chest imaging whith in the radiology department by means of photostimulable phosphor computerd radiography. J Digit lmaging, 1992, 5: 67
8Chen SK. Hollender L. Digitizung of radiograohs with a flathed scanner. J dent, 1995,23: 205
9Svanes DB, Moystad A, Risnes S. et al. Intraoral storage phosphor radiography for approximal caries detection and effect of image magnification. Oral Surg, 1996.82: 94
