Mejias JE, Griffin TJ.  The absorbable synthetic sutures.  Cont Ed                                1983;4:567-572

            Zetterqvist L, Anneroth G, Danin J, Roding K.  Microleakage of retrograde fillings – a comparative investigation between amalgam and glass ionomer cement in vitro.  Int Endod J 1988;21:1-8

            Bondra DL, Hartwell GR, MacPherson MG, Portell FR.  Leakage in vitro with IRM, high copper amalgam and EBA cement as retrofilling materials.  J Endodon  1989;15:157-160

            Thirawat J, Edmunds DH.  The sealing ability of materials used as                               retrograde root fillings in endodontic surgery.  Int Endo J  1989;22:295-298

            Friedman S, Rotstein I, Mahamid A. In vivo efficavy of various retrofills and of CO2 laser in apical surgery. Endod Dent Traumatol  1991;7:19-25

            Gilheany PA, Figdor D, Tyas MJ.  Apical dentin permeability and                                 microleakage associated with root end resection and retrograde filling.  J                   Endodon 1994;20:22-25

            Torabinejad M, Smith P, Kettering JD, Pitt Ford T.  Comparative investigation of marginal adaptation of mineral trioxide aggregate and other commonly used root-end filling materials.  J Endodon 1995;21:295-299

            Vignaroli PA, Anderson RW, Pashley DH.  Longitudinal evaluation of the microleakage of dentin bonding agents used to seal resected root apices.  J Endodon 1995;21:509-512

            Trope M Lost C, Schmitz HJ, Friedman S.  Healing of apical periodontitis in dogs after apicoectomy and retrofilling with various filling materials.  Oral Surg 1996;81:221-228

            Torabinejad M, Pitt Ford TR, McKendry DJ, Abedi HR, Miller DA, Kariyawasam SP, Histologic assessment of mineral trioxide aggregate as a root-end filling in monkeys.  J Endodon 1997;23:225-228

            Pecora G, Andreana S, Margarone JE, Covani U, Sottosanti JS.  Bone                      regeneration with a calcium sulfate barrier. Oral Surg 1997;84:424-429

            von Arx T, Walker WA.  Microsurgical instruments for root-end cavity
            preparation following apicoectomy: a literature review.  Endod Dent Traumatol 2000;16:47-60

            Scheerer SQ, Steinman HR, Cohen J.  A comparative evaluation of three root-end filling materials: an in vitro leakage study using Prevotella nigrescens.  J Endodon 2001;27:40-42

            Douthitt JC, Gutmann JL, Witherspoon DE.  Histologic assessment of healing after the use of a bioresorbable membrane in the management of a buccal bone loss with concomitant periradicular surgery.  J Endodon 2001;27:404-410
           
            Fogel HM, Peikoff MD.  Microleakage of root-end filling materials.  J Endodon 2001;27:456:458

            Siqueira JF, Rocas IN, Abad EC, Castro AJR, Gahyva SM, Favieri A.  Ability of three root-end filling materials to prevent bacterial leakage.  J Endodon 2001;27:673-675

            Tang HM, Torabinejad M, Kettering JD.  Leakage evaluation of root end filling materials using endotoxin. J Endodon 2002;28:5-7

            Garrett K, Kerr M, Hartwell G, O’Sullivan S, mayer P.  The effect of a bioresorbable matrix barrier in endodontic surgery on the rate of periapical healing: an in vivo study. J Endodon 2002;28:503-506

            Regan JD, Gutmann JL, Witherspoon DE.  Comparison of diaket and MTA when used as root-end filling materials to support regeneration of the periradicular tissues.  Int Endod J 2002;35:840-847

            Economides N, Pantelidou O, Kokkas A, Tziafas D.  Short-term periradicular tissue response to mineral trioxide aggregate (MTA) as root-end filling material.  Int Endod J 2003:44-48         

            Vy CH, Baumgartner JC, Marshall JG.  Cardiovascular effects and efficacy of ahemostatic agent in periradicuar surgery.  J Endodon 2004;30:379-383

            Baek SH, Plenk H, Kim S.  Periapical tissue responses and cementum regeneration with amalgam, super EBA, and MTA as root-end filling materials.  J Endodon 2005;31:444-449

            Root-end filling materials; rationale and tissue response.  Endo Topics 2005;11:114-130

Optional

            Richman MJ. The use of ultrasonics in root canal therapy and root resection. J Dent Med 1957;12:12-18
            Feldman G, Nyborg H.  Tissue reactions to root filling materials I. Comparison between gutta percha and silver amalgam implanted in rabbit.  Odont Revy  1962;13:1-14
            Delivanis P, Tabibi A.  A comparative sealability study of different retrofilling materials.  Oral Surg  1978;45:273-281
            Oynick J, Oynick T.  A Study of a new material for retrograde fillings.  J                        Endodon  1978;4:203-206
            Tanzilli JP, Raphael D, Moodnik RM.  A comparison of the marginal adaptation of retrograde techniques: A scanning electron microscopic study.  Oral Surg.  1980;50:74-80
            Kos WL, Aulozzi DP, Gerstein H.  A comparative study of retrofilling                materials.  J Endodon  1982;8:355-358
            Kimura JT.  A comparative analysis of zinc and non-zinc alloys used in           
            retrograde surgery.  Part 1: apical seal and tissue reaction.  J Endodon                      1982;8:359-363
            Kimura JT.  A comparative analysis of zinc and non-zinc alloys used in retrograde surgery.  Part 2: Optical emission spectrographic analysis for zinc precipitation.  J Endodon  1982;8:407-409
Szeremeta-Browar TL, VanCura JE, Zaki AE.  A comparison of the sealing properties of different retrograde techniques: An autoradiographic study. Oral Surg  1985;59:82-87
            Stabholz A, Shani J, Friedman S, Abed J.  Marginal adaptation of retrograde fillings and its correlation with sealability.  J Endodon  1985;11:218-223
            Escobar C, Michanowicz AE, Czonstkowsky M, Miklos FL.  A comparative study between injectable low-temperature (70 C) gutta-percha and silver amalgam as a retroseal.  Oral Surg  1986;61:504-507
            Zetterqvist L, Anneroth G, Nordenram A.  Glass-ionomer cement as                 retrograde filling material.  Int J Oral Maxillofac Surg  1987;16:459-464
            Smee G, Bolanos OR, Morse DR, Furst ML, Yesilsoy C.  A comparative leakage study of P-30 resin bonded ceramic, teflon, amalgam, and IRM as retrofilling seals.  J Endodon  1987;13:117-121
            McDonald NJ, Dumsha TC.  A comparative retrofill leakage study utilizing a dentin bonding material.  J Endodon  1987;13:224-227
            Negm MM.  The effect of varnish and pit and fissure sealants on the sealing capacity of retrofilling techniques.  Oral Surg  1988;66:483-488
            Friedman S, Rotstein I, Koren L, Trope, M. Dye leakage in retrofilled dog teeth and its correlation with radiographic healing. J Endodon 1991;17:392-395
            MacDonald A, Moore K, Newton C, Brown C.  Evaluation of an apatite                        cement as a root end filling material.  J Endodon 1994;20:598-604
            Kaplan SD, Tanzilli JP, Raphael D, Moodnik RM.  A comparison of the           marginal leakage of retrograde techniques.  Oral Surg  1982;54:583-585
            Barkhordar RA, Pelzner RB, Stark MM. Use of glass ionomers as retrofilling materials. Oral Surg 1989;67:734-739
            Yoshimura M, Marshall FJ, Tinkle JS.  In vitro quantification of the apical          sealing ability of retrograde amalgam fillings.  J Endodon  1990:16:9-12
            Pitt Ford TR, Roberts GJ.  Tissue response to glass ionomer retrograde root fillings. Int Endodon J 1990;23:233-238
            Frank AL, Glick DH, Patterson SS, Weine FS. Long-term evaluation of                       surgically placed amalgam fillings. J Endodon 1992;18:391-398
            Chong BS, Pitt Ford TR, Kariyawasam SP.  Tissue response to potential root-end filling materials in infected root canals.  Int Endodon J 1997;30:102-114
            Zetterqvist L, Hall G, Holmlund A. Apicectomy: A comparative clinical study of amalgam and glass ionomer as apical sealants. Oral Surg  1991;71:489-491
            Bohning B, Davenport W, Jeansonne B.  The effect of guided tissue regeneration on the healing of osseous defects in rat calvaria.  J Endodon 1999;25:81-82
            Minnich SG, Hartwell GR, Portell FR.  Does cold burnishing gutta-percha        create a better apical seal.  J Endodon  1989;15:204-209
            Greer BD, West LA, Liewehr FR, Pashley DH.  Sealing ability of dyract, geristore, IRM, and super eba as root-end filling materials.  J Endodon 2001 27;441-443
            Snyder-Williams S, Gutmann JL.  Periradicular healing response to diaket root-end filling material with and without tricalcium phosphate.  Int Endodon J 1996;29:84-92
            Nelson LW, Mahler DB.  Factors influencing the sealing behavior of                 retrograde amalgam fillings.  Oral Surg  1990;69:356-360
            Abdul AK, Retief DH.  The apical seal via the retrosurgical approach 1. A preliminary study.  Oral Surg 1982; 53:614-621
            Tronstad L, Trope M, Doering A, Hasselgren G.  Sealing ability of dental         amalgams as retrograde fillings in endodontic therapy.  J Endodon                                      1983;9:551-553
            Mattison GD, von Fraunhofer JA, Delivanis P, Anderson AN.  Microleakage of retrograde amalgams.  J Endodon  1985;11:340-345
            Bramwell JD, Hicks ML.  Sealing ability of four retrofilling techniques.  J                      Endodon 1986;12:95-100
Johnson JR, Anderson RW, Pashley DH.  Evaluation of the seal of various amalgam products used as root-end fillings.  J Endodon 1995;21:505-508