Effect of intracanal diode laser irradiation on fracture resistance of roots restored with CAD/CAM posts





Lasers, Endodontics, Dentistry, Computer-aided design


Aim: To evaluate the fracture resistance of roots restored with CAD/CAM-fabricated posts, receiving or not intracanal laser treatment, compared with glass fiber posts under mechanical cycling. Methods: Twenty-seven endodontically treated, single-rooted teeth were divided into 3 groups: group 1 (control), prefabricated glass fiber posts relined with resin composite; group 2, CAD/CAM-fabricated intraradicular posts using Resin Nano Ceramic (RNC) blocks; and group 3, CAD/CAM-fabricated intraradicular posts using RNC blocks in canals irradiated with a 940-nm diode laser (100 mJ, 300-um optic fiber, coronal-apical and apical-coronal helical movements, speed of 2 mm/second, 4 times each canal). After cementation of the coping, cyclic loading was applied at an angle of 135° to the long axis of the root, with a pulse load of 130 N, frequency of 2.2 Hz, and 150,000 pulses on the crown at a point located 2 mm below the incisal edge on the lingual aspect of the specimen. Every 50,000 cycles, the specimens were evaluated for root fracture occurring below or above the simulated bone crest. Results were analyzed by one-way ANOVA followed by Tukey’s test (p<0.05). Results: Group 1 was the least resistant, while groups 2 and 3 were the most resistant. Group 1 differed significantly from groups 2 and 3 (p<0.01), but there was no difference between groups 2 and 3 (p<0.01). Conclusion: Treatment of the intracanal surface with diode laser had no influence on fracture resistance of roots restored with CAD/CAM-fabricated posts, but a longer cycling time is required to evaluate the real benefits of diode laser irradiation.


Download data is not yet available.


Metrics Loading ...

Author Biographies

Flavia Florentino Teixeira da Silva, Cruzeiro do Sul University

Graduate Program in Dentistry, Cruzeiro do Sul University, São Paulo, SP, Brazil.

André Hayato Saguchi, Cruzeiro do Sul University

Graduate Program in Dentistry, Cruzeiro do Sul University, São Paulo, SP, Brazil.

Sidnea Aparecida Freitas Paiva, Cruzeiro do Sul University

Graduate Program in Dentistry, Cruzeiro do Sul University, São Paulo, SP, Brazil.

Guilherme Espósito Pires, Cruzeiro do Sul University

Graduate Program in Dentistry, Cruzeiro do Sul University, São Paulo, SP, Brazil.

Mariana Isidoro, Cruzeiro do Sul University

Graduate Program in Dentistry, Cruzeiro do Sul University, São Paulo, SP, Brazil.

Aldo Brugnera Junior, Camilo Castelo Branco University

Camilo Castelo Branco University, São Paulo, SP, Brazil.

Paulo Francisco Cesar, University of São Paulo

Department of Biomaterials and Oral Biology, School of Dentistry, University of São Paulo (USP), São Paulo, Brazil.

Ângela Toshie Araki, Cruzeiro do Sul University

Graduate Program in Dentistry, Cruzeiro do Sul University, São Paulo, SP, Brazil.


Novais VR, Rodrigues RB, Simamoto Junior PC, Lourenco CS, Soares CJ. Correlation between the Mechanical Properties and Structural Characteristics of Different Fiber Posts Systems. Braz Dent J. 2016;27(1):46-51. doi: 10.1590/0103-6440201600377.

Barbosa Kasuya AV, Favarão IN, Machado AC, Rezende Spini PH, Soares PV, Fonseca RB. Development of a fiber-reinforced material for fiber posts: Evaluation of stress distribution, fracture load, and failure mode of restored roots. J Prosthet Dent. 2020 Jun;123(6):829-38. doi: 10.1016/j.prosdent.2019.04.026.

Pasqualin FH, Giovani AR, De Sousa Neto MD, Paulino SM, Vansan LP. In vitro fracture resistance of glass-fiber and cast metal posts with different designs. Rev Odonto Ciênc. 2012;27(1):52-7. doi: 10.1590/S1980-65232012000100010.

Chen A, Feng X, Zhang Y, Liu R, Shao L. Finite element analysis to study the effects of using CAD/CAM glass-fiber post system in a severely damaged anterior tooth. Biomed Mater Eng. 2015;26 Suppl 1:S519-25. doi: 10.3233/BME-151341.

Sary SB, Samah MS, Walid AA. Effect of restoration technique on resistance to fracture of endodontically treated anterior teeth with flared root canals. J Biomed Res. 2019 Apr 22;33(2):131-8. doi: 10.7555/JBR.32.20170099.

Pang J, Feng C, Zhu X, Liu B, Deng T, Gao Y, et al. Fracture behaviors of maxillary central incisors with flared root canals restored with CAD/CAM integrated glass fiber post-and-core. Dent Mater J. 2019 Feb 8;38(1):114-9. doi: 10.4012/dmj.2017-394.

Garcia PP, da Costa RG, Garcia AV, Gonzaga CC, Cunha LF, Rezende CEE, et al. Effect of surface treatments on the bond strength of CAD/CAM fiberglass posts. J Clin Exp Dent. 2018 Jun 1;10(6):e591-7. doi: 10.4317/jced.54904.

Eid R, Azzam K, Skienhe H, Ounsi H, Ferrari M, Salameh Z. Influence of adaptation and adhesion on the retention of computer-aided design/computer-aided manufacturing glass fiber posts to root canal. J Contemp Dent Pract. 2019 Sep;20(9):1003-8.

Mannocci F, Bertelli E, Sherriff M, Watson TF, Ford TR. Three-year clinical comparison of survival of endodontically treated teeth restored with either full cast coverage or with direct composite restoration. J Prosthet Dent. 2002 Sep;88(3):297-301. doi: 10.1067/mpr.2002.128492.

Mjor IA, Smith MR, Ferrari M, Mannocci F. The structure of dentine in the apical region of human teeth. Int Endod J. 2001 Jul;34(5):346-53. doi: 10.1046/j.1365-2591.2001.00393.x.

Gutknecht N, Alt T, Slaus G, Bottenberg P, Rossel P, Lauwers S, et al. A clinical comparison of the bactericidal effect of the diode laser and 5% sodium hypochlorite in necrotic root canals. J Oral Laser Applications. 2002;2(3):151-7.

Gutknecht N, Franzen R, Meister J, Vanweersch L, Mir M. Temperature evolution on human teeth root surface after diode laser assisted endodontic treatment. Lasers Med Sci. 2005 Sep;20(2):99-103. doi: 10.1007/s10103-005-0347-9.

Akyuz Ekim SN, Erdemir A. Effect of different irrigant activation protocols on push-out bond strength. Lasers Med Sci. 2015 Nov;30(8):2143-9. doi: 10.1007/s10103-015-1772-z.

Borges CC, Palma-Dibb RG, Rodrigues FCC, Plotegher F, Rossi-Fedele G, de Sousa-Neto MD, et al. The Effect of Diode and Er,Cr:YSGG Lasers on the bond strength of fiber posts. Photobiomodul Photomed Laser Surg. 2020 Feb;38(2):66-74. doi: 10.1089/photob.2019.4668.

Alonaizan FA, Alofi RS, AlFawaz YF, Alsahhaf A, Al-Aali KA, Vohra F, et al. Effect of Photodynamic Therapy, Er,Cr:YSGG, and Nd:YAG Laser on the push-out bond strength of fiber post to root dentin. Photobiomodul Photomed Laser Surg. 2020 Jan;38(1):24-9. doi: 10.1089/photob.2019.4687.

Nasher R, Hilgers RD, Gutknecht N. Debris and Smear Layer Removal in Curved Root Canals Using the Dual Wavelength Er,Cr:YSGG/Diode 940 nm Laser and the XP-Endoshaper and Finisher Technique. Photobiomodul Photomed Laser Surg. 2020 Mar;38(3):174-80. doi: 10.1089/photob.2019.4693.

Erkut S, Eminkahyagil N, Imirzalioglu P, Tunga U. A technique for restoring an overflared root canal in an anterior tooth. J Prosthet Dent. 2004;92:581-3.

Yoldas O, Akova T, Uysal H. An experimental analysis of stresses in simulated flared root canals subjected to various post-core applications. J Oral Rehabil. 2004 Dec;92(6):581-3. doi: 10.1016/j.prosdent.2004.08.016.

Mitsui FH, Marchi GM, Pimenta LA, Ferraresi PM. In vitro study of fracture resistance of bovine roots using different intraradicular post systems. Quintessence Int. 2004 Sep;35(8):612-6.

Silva GR, Santos-Filho PC, Simamoto-Junior PC, Martins LR, Mota AS, Soares CJ. Effect of post type and restorative techniques on the strain and fracture resistance of flared incisor roots. Braz Dent J. 2011;22(3):230-7. doi: 10.1590/s0103-64402011000300009.

Ferrari M, Vichi A, Garcia-Godoy F. Clinical evaluation of fiber-reinforced epoxy resin posts and cast post and cores. Am J Dent. 2000 May;13(Spec n.):15B-18B.

Ferrari M, Cagidiaco MC, Goracci C, Vichi A, Mason PN, Radovic I, et al. Long-term retrospective study of the clinical performance of fiber posts. Am J Dent. 2007 Oct;20(5):287-91.

Akkayan B, Gulmez T. Resistance to fracture of endodontically treated teeth restored with different post systems. J Prosthet Dent. 2002 Apr;87(4):431-7. doi: 10.1067/mpr.2002.123227.

Giovani AR, Vansan LP, de Sousa Neto MD, Paulino SM. In vitro fracture resistance of glass-fiber and cast metal posts with different lengths. J Prosthet Dent. 2009 Mar;101(3):183-8. doi: 10.1016/S0022-3913(09)60025-1.

Hayashi M, Takahashi Y, Imazato S, Ebisu S. Fracture resistance of pulpless teeth restored with post-cores and crowns. Dent Mater. 2006 May;22(5):477-85. doi: 10.1016/j.dental.2005.03.017.

Li Q, Yan P, Chen Z. Fracture resistance and failure patterns of open apex root teeth with different posts after endodontic treatment. J Huazhong Univ Sci Technolog Med Sci. 2011 Apr;31(2):271. doi: 10.1007/s11596-011-0265-y.

Padmanabhan P. A comparative evaluation of the fracture resistance of three different pre-fabricated posts in endodontically treated teeth: an in vitro study. J Conserv Dent. 2010 Jul;13(3):124-8. doi: 10.4103/0972-0707.71642.

Coelho CS, Biffi JC, Silva GR, Abrahao A, Campos RE, Soares CJ. Finite element analysis of weakened roots restored with composite resin and posts. Dent Mater J. 2009 Nov;28(6):671-8. doi: 10.4012/dmj.28.671.

Spazzin AO, Galafassi D, de Meira-Junior AD, Braz R, Garbin CA. Influence of post and resin cement on stress distribution of maxillary central incisors restored with direct resin composite. Oper Dent. 2009;34(2):223-9. doi: 10.2341/08-73.

Wandscher VF, Bergoli CD, Limberger IF, Ardenghi TM, Valandro LF. Preliminary results of the survival and fracture load of roots restored with intracanal posts: weakened vs nonweakened roots. Oper Dent. 2014;39(5):541-55. doi: 10.2341/12-465.

Wandscher VF, Bergoli CD, de Oliveira AF, Kaiser OB, Borges ALS, Limberguer IF, et al. Fatigue surviving, fracture resistance, shear stress and finite element analysis of glass fiber posts with different diameters. J Mech Behav Biomed Mater. 2015 Mar;43:69-77. doi: 10.1016/j.jmbbm.2014.11.016.

Rezaei Dastjerdi M, Amirian Chaijan K, Tavanafar S. Fracture resistance of upper central incisors restored with different posts and cores. Restor Dent Endod. 2015 Aug;40(3):229-35. doi: 10.5395/rde.2015.40.3.229.

Rippe MP, Santini MF, Bier CA, Baldissara P, Valandro LF. Effect of root canal preparation, type of endodontic post and mechanical cycling on root fracture strength. J Appl Oral Sci. 2014 Jun;22(3):165-73. doi: 10.1590/1678-775720130051.

Pegoretti A, Fambri L, Zappini G, Bianchetti M. Finite element analysis of a glass fibre reinforced composite endodontic post. Biomaterials. 2002 Jul;23(13):2667-82. doi: 10.1016/s0142-9612(01)00407-0.

Zamboni SC, Baldissara P, Pelogia F, Bottino MA, Scotti R, Valandro LF. Fatigue resistance of bovine teeth restored with resin-bonded fiber posts: effect of post surface conditioning. Gen Dent. 2008;56(1):56-9.

Schmitter M, Rammelsberg P, Gabbert O, Ohlmann B. Influence of clinical baseline findings on the survival of 2 post systems: a randomized clinical trial. Int J Prosthodont. 2007;20(2):173-8.

Spina DRF, Da Costa RG, Farias IC, Cunha LG, Ritter AV, Gonzaga CC, et al. CAD/CAM post-and-core using different esthetic materials: fracture resistance and bond strengths. Am J Dent. 2017;30(6):299-304.

Tsintsadze N, Juloski J, Carrabba M, Tricarico M, Goracci C, Vichi A, et al. Performance of CAD/CAM fabricated fiber posts in oval-shaped root canals: An in vitro study. Am J Dent. 2017;30(5):248-54.

Da Costa RG, Freire A, Caregnatto de Morais EC, Machado de Souza E, Correr GM, Rached RN. Effect of CAD/CAM glass fiber post-core on cement micromorphology and fracture resistance of endodontically treated roots. Am J Dent. 2017;30(1):3-8.

Silva RA, Coutinho M, Cardozo PI, Silva LA, Zorzatto JR. Conventional dual-cure versus self-adhesive resin cements in dentin bond integrity. J Appl Oral Sci. 2011 Aug;19(4):355-62. doi: 10.1590/s1678-77572011005000010.

Menezes MS, Queiroz EC, Campos RE, Martins LR, Soares CJ. Influence of endodontic sealer cement on fibreglass post bond strength to root dentine. Int Endod J. 2008 Jun;41(6):476-84. doi: 10.1111/j.1365-2591.2008.01378.x.

Serafino C, Gallina G, Cumbo E, Ferrari M. Surface debris of canal walls after post space preparation in endodontically treated teeth: a scanning electron microscopic study. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2004;97:381-7. 2004 Mar;97(3):381-7. doi: 10.1016/j.tripleo.2003.10.004.

Goracci C, Corciolani G, Vichi A, Ferrari M. Light-transmitting ability of marketed fiber posts. J Dent Res. 2008 Dec;87(12):1122-6. doi: 10.1177/154405910808701208.

Silva NR, Castro CG, Santos-Filho PC, Silva GR, Campos RE, Soares PV, et al. Influence of different post design and composition on stress distribution in maxillary central incisor: finite element analysis. Indian J Dent Res. 2009;20(2):153-8. doi: 10.4103/0970-9290.52888.

Oliveira PHC, Oliveira LHC, Cabral MR, Moraes AGV, Sgura R, Cesar PF, et al. Effect of surface treatment with CO2 laser on bond strength in composite resin restorations. Photobiomodul Photomed Laser Surg. 2019 Jul;37(7):428-33. doi: 10.1089/photob.2018.4534.

Lopes FC, Roperto R, Akkus A, Akkus O, Souza-Gabriel AE, Sousa-Neto MD. Effects of different lasers on organic/inorganic ratio of radicular dentin. Lasers Med Sci. 2016 Apr;31(3):415-20. doi: 10.1007/s10103-015-1862-y.

Al-Karadaghi TS, Franzen R, Jawad HA, Gutknecht N. Investigations of radicular dentin permeability and ultrastructural changes after irradiation with Er,Cr:YSGG laser and dual wavelength (2780 and 940 nm) laser. Lasers Med Sci. 2015 Nov;30(8):2115-21. doi: 10.1007/s10103-015-1757-y.

Deleu E, Meire MA, De Moor RJ. Efficacy of laser-based irrigant activation methods in removing debris from simulated root canal irregularities. Lasers Med Sci. 2015 Feb;30(2):831-5. doi: 10.1007/s10103-013-1442-y.

Da Costa Ribeiro A, Nogueira GE, Antoniazzi JH, Moritz A, Zezell DM. Effects of diode laser (810 nm) irradiation on root canal walls: thermographic and morphological studies. J Endod. 2007 Mar;33(3):252-5. doi: 10.1016/j.joen.2006.09.002.

Garcia Lda F, Naves LZ, Farina AP, Walker CM, Consani S, Pires-de-Souza FC. The effect of a 980 nm diode laser with different parameters of irradiation on the bond strength of fiberglass posts. Gen Dent. 2011;59(1):31-7; quiz 38-9, 80.

Gomes KGF, Faria NS, Neto WR, Colucci V, Gomes EA. Influence of laser irradiation on the push-out bond strength between a glass fiber post and root dentin. J Prosthet Dent. 2018 Jan;119(1):97-102. doi: 10.1016/j.prosdent.2017.01.013.




How to Cite

Silva FFT da, Saguchi AH, Paiva SAF, Pires GE, Isidoro M, Brugnera Junior A, Cesar PF, Araki Ângela T. Effect of intracanal diode laser irradiation on fracture resistance of roots restored with CAD/CAM posts. Braz. J. Oral Sci. [Internet]. 2021 Dec. 9 [cited 2022 May 25];21(00):e223759. Available from: https://periodicos.sbu.unicamp.br/ojs/index.php/bjos/article/view/8663759



Original Research

Most read articles by the same author(s)