Journal of Prosthetic Dentistry
Research and Education| Volume 124, ISSUE 6, P738.e1-738.e8, December 2020

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Bond strength and quality of bond interface of multifilament fiberglass posts luted onto flat-oval root canals without additional dentin wear after biomechanical preparation


      Statement of problem

      An intraradicular retainer formed by multiple independent glass fiber filaments was developed aiming to allow better adaptation in flattened root canals; however, the performance of the new posts is unclear.


      The purpose of this in vitro study was to compare the bond strength (BS) and adhesive interface quality achieved in flattened root canals restored with conventional glass fiber posts (CFPs) and multifilament glass fiber posts (MFPs).

      Material and methods

      The distal roots of mandibular molars with long oval root canals were endodontically treated, and the obturation material was removed and assigned to 2 groups (n=11) according to the type of retainer used: CFP (WhitePostDC#0.5; FGM) or MFP (CometTail#4; Synca). The posts were cemented with self-adhesive resin cement. The specimens were sectioned (2 slices per third). The most cervical slice in each third was used to evaluate the BS, while the adhesive interface in the apical slices was analyzed by scanning electron microscopy. BS data were analyzed by using a multilevel generalized linear model, and adhesive interface SEM data were analyzed by using a multilevel ordinal logistic regression model (α=.05).


      Multilevel regression showed a statistically significant difference for the “type of retainer” factor (P=.001; CFP 2.61 ±1.30>MFP 1.59 ±1.54). No statistically significant differences were found for the “root thirds” factor (P=.346) or for the interaction of both factors (P=.114). The failure pattern was predominantly mixed or adhesive for CFP and adhesive to dentin for MFP. A better adaptation of the restorative material was observed in the cervical third for CFP and in the apical third for MFP (P<.001).


      MFP resulted in lower BS values than CFP, with a higher prevalence of adhesive failures to dentin and better adaptation of the adhesive interface in the apical third.
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        • Monticelli F.
        • Osorio R.
        • Sadek F.T.
        • Radovic I.
        • Toledano M.
        • Ferrari M.
        Surface treatments for improving bond strength to prefabricated fiber posts: a literature review.
        Oper Dent. 2008; 33: 346-355
        • Pedreira A.P.
        • D'Alpino P.H.
        • Pereira P.N.
        • Chaves S.B.
        • Wang L.
        • Hilgert L.
        • et al.
        Effects of the application techniques of self-adhesive resin cements on the interfacial integrity and bond strength of fiber posts to dentin.
        J Appl Oral Sci. 2016; 24: 437-446
        • Macedo V.C.
        • Faria E.
        • Silva A.L.
        • Martins L.R.
        Effect of cement type, relining procedure, and length of cementation on pull-out bond strength of fiber posts.
        J Endod. 2010; 36: 1543-1546
        • Muñoz C.
        • Llena C.
        • Forner L.
        Oval fiber posts do not improve adaptation to oval-shaped canal walls.
        J Endod. 2011; 37: 1386-1389
        • Gomes G.M.
        • Monte-Alto R.V.
        • Santos G.O.
        • Fai C.K.
        • Loguercio A.D.
        • Gomes O.M.M.
        • et al.
        A use of a direct anatomic post in a flared root canal: a three-year follow-up.
        Oper Dent. 2016; 41: e23-e28
        • Wang H.W.
        • Chang Y.H.
        • Lin C.L.
        Mechanical resistance evaluation of a novel anatomical short glass fiber reinforced post in artificial endodontically treated premolar under rotational/lateral fracture fatigue testing.
        Dent Mater J. 2016; 35: 233-240
        • Rocha A.T.
        • Gonçalves L.M.
        • Vasconcelos A.J.C.
        • Matos Maia Filho E.
        • Nunes Carvalho C.
        • De Jesus Tavarez R.R.
        Effect of anatomical customization of the fiber post on the bond strength of a self-adhesive resin cement.
        Int J Dent. 2017; 2017: 5010712
        • Wang T.H.
        • Liu C.J.
        • Chao T.F.
        • Chen T.J.
        • Hu Y.W.
        Risk factors for and the role of dental extractions in osteoradionecrosis of the jaws: a national-based cohort study.
        Head Neck. 2017; 39: 1313-1321
        • Wu M.K.
        • Wesselink P.R.
        A primary observation on the preparation and obturation of oval canals.
        Int Endod J. 2001; 34: 137-141
        • Wu M.K.
        • Van Der Sluis L.W.
        • Wesselink P.R.
        The capability of two hand instrumentation techniques to remove the inner layer of dentine in oval canals.
        Int Endod J. 2003; 36: 218-224
        • Pereira R.D.
        • Brito-Júnior M.
        • Leoni G.B.
        • Estrela C.
        • De Sousa-Neto M.D.
        Evaluation of bond strength in single-cone fillings of canals with different cross-sections.
        Int Endod J. 2017; 50: 177-183
        • Wu M.K.
        • R'Oris A.
        • Barkis D.
        • Wesselink P.R.
        Prevalence and extent of long oval canals in the apical third.
        Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2000; 89: 739-743
        • Perez B.E.
        • Barbosa S.H.
        • Melo R.M.
        • Zamboni S.C.
        • Ozcan M.
        • Valandro L.F.
        • et al.
        Does the thickness of the resin cement affect the bond strength of a fiber post to the root dentin?.
        Int J Prosthodont. 2006; 19: 606-609
        • Ausiello P.
        • Ciaramella S.
        • Martorelli M.
        • Lanzotti A.
        • Zarone F.
        • Watts D.C.
        • et al.
        Mechanical behavior of endodontically restored canine teeth: effects of ferrule, post material and shape.
        Dent Mater. 2017; 33: 1466-1472
        • Pupo Y.M.
        • Casacqui E.
        • De Lima P.A.
        • Michél M.D.
        • Bueno A.L.
        • Michelotto A.L.
        Morphology of root canal surface: a reflection on the process of cementation of the composite relined glass fiber post.
        Indian J Dent Res. 2017; 28: 59-65
        • Demarco F.F.
        • Correa M.B.
        • Cenci M.S.
        • Moraes R.R.
        • Opdam N.J.
        Longevity of posterior composite restorations: not only a matter of materials.
        Dent Mater. 2012; 28: 87-101
        • Topçuoglu H.S.
        • Demirbuga S.
        • Tuncay O.
        • Pala K.
        • Arslan H.
        • Karatas E.
        The effects of Mtwo, R-Endo, and D-RaCe retreatment instruments on the incidence of dentinal defects during the removal of root canal filling material.
        J Endod. 2014; 40: 266-270
        • Wei X.
        • Hu B.
        • Peng H.
        • Tang M.
        • Song J.
        The incidence of dentinal cracks during root canal preparations with reciprocating single-file and rotary-file systems: a meta-analysis.
        Dent Mater J. 2017; 36: 243-252
        • Lopes F.C.
        • Roperto R.
        • Akkus A.
        • de Queiroz A.M.
        • Francisco de Oliveira H.
        • Sousa-Neto M.D.
        Effect of carbodiimide and chlorhexidine on the bond strength longevity of resin cement to root dentine after radiation therapy.
        Int Endod J. 2020; 53: 539-552
        • Balguerie E.
        • Vandersluis L.
        • Vallaeys K.
        • Gurgel-Georgelin M.
        • Diemer F.
        Sealer penetration and adaptation in the dentinal tubules: a scanning electron microscopic study.
        J Endod. 2011; 37: 1576-1579
        • Bürklein S.
        • Flüch S.
        • Schäfer E.
        Shaping ability of reciprocating single-file systems in severely curved canals: WaveOne and Reciproc versus WaveOne Gold and Reciproc blue.
        Odontology. 2019; 107: 96-102
        • Hofmann N.
        Both operator and heat treatment determine the centring ability of Reciproc® files in vitro.
        Clin Oral Investig. 2019; 23: 697-706
        • Baldissara P.
        • Zicari F.
        • Valandro L.F.
        Effect of fiber posts with different emerging diameters on the fracture strength of restored crownless teeth.
        Gen Dent. 2011; 59: 67-71
        • Santos-Filho P.C.
        • Veríssimo C.
        • Soares P.V.
        • Saltarelo R.C.
        • Soares C.J.
        • Martins L.R.M.
        Influence of ferrule, post system, and length on biomechanical behavior of endodontically treated anterior teeth.
        J Endod. 2014; 1: 119-123
        • Tey K.C.
        • Lui J.L.
        The effect of glass fiber-reinforced epoxy resin dowel diameter on the fracture resistance of endodontically treated teeth.
        J Prosthodont. 2014; 23: 572-581
        • Guldener K.A.
        • Lanzrein C.L.
        • Siegrist Guldener B.E.
        • Lang N.P.
        • Ramseier C.A.
        • Salvi G.E.
        Long-term clinical outcomes of endodontically treated teeth restored with or without fiber post-retained single-unit restorations.
        J Endod. 2016; 43: 188-193
        • Rossi-Fedele G.
        • Musu D.
        • Cotti E.
        • Dogramaci E.J.
        Root canal treatment versus single-tooth implant: a systematic review of internet content.
        J Endod. 2016; 42: 846-853
        • Silva E.
        • Belladonna F.G.
        • Zuolo A.S.
        • Rodrigues E.
        • Ehrhardt I.C.
        • Souza E.M.
        • et al.
        Effectiveness of XP-endo Finisher and XP-endo Finisher R in removing root filling remnants: a micro-CT study.
        Int Endod J. 2018; 51: 86-91
        • Giachetti L.
        • Scaminaci Russo D.
        • Bertini F.
        • Giuliani V.
        Translucent fiber post cementation using a light-curing adhesive/composite system: SEM analysis and pull-out test.
        J Dent. 2004; 32: 629-634
        • Penelas A.G.
        • Piedade V.M.
        • Borges A.C.
        • Poskus L.T.
        • Da Silva E.M.
        • Guimarães J.G.
        Can cement film thickness influence bond strength and fracture resistance of fiber reinforced composite posts?.
        Clin Oral Investig. 2016; 20: 849-855
        • Souza N.C.
        • Marcondes M.L.
        • Breda R.V.
        • Weber J.B.
        • Mota E.G.
        • Spohr A.M.
        Relined fiberglass post: an ex vivo study of the resin cement thickness and dentin-resin interface.
        Braz Oral Res. 2016; 30
        • Chang Y.H.
        • Wang H.W.
        • Lin P.H.
        • Lin C.L.
        Evaluation of early resin luting cement damage induced by voids around a circular fiber post in a root canal treated premolar by integrating micro-CT, finite element analysis and fatigue testing.
        Dent Mater. 2018; 34: 1082-1088
        • Soares C.J.
        • Pareira J.C.
        • Souza S.J.
        • Menezes M.S.
        • Armstrong S.R.
        The effect of prophylaxis method on microtensile bond strength of indirect restorations to dentin.
        Oper Dent. 2012; 37: 602-609
        • Skupien J.A.
        • Sarkis-Onofre R.
        • Cenci M.S.
        • Moraes R.R.
        • Pereira-Cenci T.A.
        A systematic review of factors associated with the retention of glass fiber posts.
        Braz Oral Res. 2015; 29
        • Mamede-Neto I.
        • Borges Á.H.
        • Alencar A.H.G.
        • Duarte M.A.H.
        • Sousa Neto M.D.
        • Estrela C.
        Multidimensional analysis of curved root canal preparation using continuous or reciprocating nickel-titanium instruments.
        Open Dent J. 2018; 12: 32-45
        • Bohrer T.C.
        • Fontana P.E.
        • Wandscher V.F.
        • Morari V.H.C.
        • Dos Santos S.S.
        • Valandro L.F.
        • et al.
        Endodontic sealers affect the bond strength of fiber posts and the degree of conversion of two resin cements.
        J Adhes Dent. 2018; 20: 165-172