Fracture Resistance of a Bulk-Fill and a Conventional Composite and a Combination of both for Coronal Restoration of Severely Damaged Primary Anterior Teeth
,
Abstract
Objectives: This study aimed to compare the fracture resistance of a bulk-fill and a conventional composite and a combination of both for coronal restoration of severely damaged primary anterior teeth.
Materials and Methods: In this in vitro experimental study, 45 primary anterior teeth were randomly divided into three groups. After root canal preparation, the canals were filled with Metapex paste such that after the application of 1 mm of light-cure liner, 3 mm of the coronal third of the canal remained empty for composite post fabrication. Filtek Z250 conventional composite was used in group 1, Sonic-Fill bulk-fill composite was used in group 2 and Sonic-Fill with one layer of Filtek Z250 as the veneering were used in group 3. Adper Single Bond 2 was used in all groups. The teeth were thermocycled, and fracture resistance was measured by a universal testing machine. The mode of fracture was categorized as repairable or irreparable. Data were analyzed using one-way ANOVA.
Results: The mean fracture resistance was 307.00±74.72, 323.31±84.28 and 333.30±63.96 N in groups 1 to 3, respectively (P=0.55). The mean fracture strength was 14.53±2.98, 15.08±2.82 and 15.26±3.02 MPa in groups 1 to 3, respectively (P=0.77). The frequency of repairable mode of failure was 80% for the conventional, 73.6% for the bulk-fill and 80% for the bulk-fill plus conventional group, with no significant difference (P>0.05).
Conclusions: Bulk-fill composites can be used for coronal reconstruction of severely damaged primary anterior teeth similar to conventional composites to decrease the treatment time in pediatric patients.
1. Eshghi A, Kowsari-Isfahan R, Khoroushi M. Evaluation of three restorative techniques for primary anterior teeth with extensive carious lesions: a 1-year clinical study. J Dent Child (Chic). 2013 May-Aug;80(2):80-7.
2. Berkowitz RJ. Causes, treatment and prevention of early childhood caries: a microbiologic perspective. J Can Dent Assoc. 2003 May;69(5):304-7.
3. Bayrak S, Tunc ES, Tuloglu N. Polyethylene fiber-reinforced composite resin used as a short post in severely decayed primary anterior teeth: a case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 May;107(5):e60-4.
4. Judd PL, Casas MJ. Psychosocial perceptions of premature tooth loss in children. Ont Dent. 1995 Oct;72(8):16-8.
5. Eidelman E, Faibis S, Peretz B. A comparison of restorations for children with early childhood caries treated under general anesthesia or conscious sedation.Pediatr Dent. 2000 Jan-Feb;22(1):33-7.
6. Vargas CM, Ronzio CR. Disparities in early childhood caries.BMC Oral Health. 2006 Jun 15;6 Suppl 1:S3.
7. Holan G, Rahme MA, Ram D. Parents' attitude toward their children's appearance in the case of esthetic defects of the anterior primary teeth. J Clin Pediatr Dent. 2009 Winter;34(2):141-5.
8. Waggoner WF. Restoring primary anterior teeth. Pediatr Dent. 2002 Sep-Oct;24(5):511-6.
9. Memarpour M, Shafiei F, Abbaszadeh M. Retentive strength of different intracanal posts in restorations of anterior primary teeth: an in vitro study. Restor Dent Endod. 2013 Nov;38(4):215-21.
10. Kwon Y, Ferracane J, Lee I-B. Effect of layering methods, composite type, and flowable liner on the polymerization shrinkage stress of light cured composites. Dent Mater. 2012 Jul;28(7):801-9.
11. Park J, Chang J, Ferracane J, Lee IB. How should composite be layered to reduce shrinkage stress: incremental or bulk filling? Dent Mater. 2008 Nov;24(11):1501-5.
12. Soares CJ, Bicalho AA, Tantbirojn D, Versluis A. Polymerization shrinkage stresses in a premolar restored with different composite resins and different incremental techniques. J Adhes Dent. 2013 Aug;15(4):341-50.
13. Abbas G, Fleming G, Harrington E, Shortall A, Burke F. Cuspal movement and microleakage in premolar teeth restored with a packable composite cured in bulk or in increments. J Dent. 2003 Aug;31(6):437-44.
14. Alrahlah A, Silikas N, Watts D. Post-cure depth of cure of bulk fill dental resin-composites. Dent Mater. 2014 Feb;30(2):149-54.
15. Goracci C, Cadenaro M, Fontanive L, Giangrosso G, Juloski J, Vichi A, et al. Polymerization efficiency and flexural strength of low-stress restorative composites. Dent Mater. 2014 Jun;30(6):688-94.
16. Garoushi S, Säilynoja E, Vallittu PK, Lassila L. Physical properties and depth of cure of a new short fiber reinforced composite. Dent Mater. 2013 Aug;29(8):835-41.
17. Van Ende A, Mine A, De Munck J, Poitevin A, Van Meerbeek B. Bonding of low-shrinking composites in high C-factor cavities. J Dent. 2012 Apr;40(4):295-303.
18. Ilie N, Schoner C, Bucher K, Hickel R. An in-vitro assessment of the shear bond strength of bulk-fill resin composites to permanent and deciduous teeth. J Dent. 2014 Jul;42(7):850-5.
19. Bucuta S, Ilie N. Light transmittance and micro-mechanical properties of bulk fill vs. conventional resin based composites. Clin Oral Investig. 2014 Nov;18(8):1991-2000.
20. Ilie N, Bucuta S, Draenert M. Bulk-fill resin-based composites: an in vitro assessment of their mechanical performance. Oper Dent. 2013 Nov-Dec;38(6):618-25.
21. Kim RJ, Kim YJ, Choi NS, Lee IB. Polymerization shrinkage, modulus, and shrinkage stress related to tooth-restoration interfacial debonding in bulk-fill composites. J Dent. 2015 Apr;43(4):430-9.
22. Didem A, Gözde Y, Nurhan Ö. Comparative mechanical properties of bulk-fill resins. J Compos. Mater. 2014 Apr;4(02):117.
23. Eunice C, Margarida A, João CL, Filomena B, Anabela P, Pedro A, et al. 99mTc in the evaluation of microleakage of composite resin restorations with SonicFillTM. An in vitro experimental model. Open J Stomatol. 2012 Oct;2(04):340.
24. Poggio C, Chiesa M, Scribante A, Mekler J, Colombo M. Microleakage in class II composite restorations with margins below the CEJ: in vitro evaluation of different restorative techniques. Med Oral Patol Oral Cir Bucal. 2013 Sep 1;18(5):e793-8.
25. Aminabadi NA, Farahani RM. The efficacy of a modified omega wire extension for the treatment of severely damaged primary anterior teeth. J Clin Pediatr Dent. 2009 Summer;33(4):283-8.
26. Subramaniam P, Girish Babu K, Sunny R. Glass fiber reinforced composite resin as an intracanal post–a clinical study. J Clin Pediatr Dent. 2008 Spring;32(3):207-10.
27. Paryab M, Afshar H, Seraj B, Shakibapoor S, Kharazifard MJ. Fracture strength of severely damaged primary anterior teeth after restoration with composite resin and resin-modified glass ionomer cement. J Islam Dent Assoc Iran 2016 Apr;28(2):57-63.
28. Grewal N, Seth R. Comparative in vivo evaluation of restoring severely mutilated primary anterior teeth with biological post and crown preparation and reinforced composite restoration. J Indian Soc Pedod Prev Dent. 2008 Dec;26(4):141-8.
29. Judd PL, Kenny DJ, Johnston DH, Yacobi R. Composite resin short-post technique for primary anterior teeth. J Am Dent Assoc. 1990 May;120(5):553-5.
30. Seraj B, Ghadimi S, Estaki Z, Fatemi M. Fracture resistance of three different posts in restoration of severely damaged primary anterior teeth: An in vitro study. Dent Res J (Isfahan). 2015 Jul-Aug;12(4):372-8.
31. Magne P, Belser UC. Porcelain versus composite inlays/onlays: effects of mechanical loads on stress distribution, adhesion, and crown flexure. Int J Periodontics Restorative Dent. 2003 Dec;23(6):543-55.
32. Ausiello P, De AG, Rengo S, Davidson C. Fracture resistance of endodontically-treated premolars adhesively restored. Am J Dent. 1997 Oct;10(5):237-41.
33. Atalay C, Yazici A, Horuztepe A, Nagas E, Ertan A, Ozgunaltay G. Fracture resistance of endodontically treated teeth restored with bulk fill, bulk fill flowable, fiber-reinforced, and conventional resin composite. Oper Dent. 2016 Sep-Oct;41(5):E131-40.
34. Galvan RR, West LA, Liewehr FR, Pashley DH. Coronal microleakage of five materials used to create an intracoronal seal in endodontically treated teeth. J Endod. 2002 Feb;28(2):59-61.
35. Gencoglu N, Pekiner FN, Gumru B, Helvacioglu D. Periapical status and quality of root fillings and coronal restorations in an adult Turkish subpopulation. Eur J Dent. 2010 Jan;4(1):17-22.
36. Fathi B, Bahcall J, Maki JS. An in vitro comparison of bacterial leakage of three common restorative materials used as an intracoronal barrier. J Endod. 2007 Jul;33(7):872-4.
37. Carvalho RMd, Pereira JC, Yoshiyama M, Pashley DH. A review of polymerization contraction: The influence of stress development versus stress relief. Oper Dent. 1996 Jan-Feb;21(1):17-24.
38. Pithan S, de Sousa Vieira R, Chain MC. Tensile bond strength of intracanal posts in primary anterior teeth: an in vitro study. J Clin Pediatr Dent. 2002 Fall;27(1):35-9.
39. Isufi A, Plotino G, Grande NM, Ioppolo P, Testarelli L, Bedini R, et al. Fracture resistance of endodontically treated teeth restored with a bulkfill flowable material and a resin composite. Ann Stomatol (Roma). 2016 Jul 19;7(1-2):4-10.
40. Taha N, Maghaireh G, Ghannam A, Palamara J. Effect of bulk-fill base material on fracture strength of root-filled teeth restored with laminate resin composite restorations. J Dent. 2017 Aug;63:60-64.
41. Ilie N, Kessler A, Durner J. Influence of various irradiation processes on the mechanical properties and polymerisation kinetics of bulk-fill resin based composites. J Dent. 2013 Aug;41(8):695-702.
42. Agarwal RS, Hiremath H, Agarwal J, Garg A. Evaluation of cervical marginal and internal adaptation using newer bulk fill composites: An in vitro study. J Conserv Dent. 2015 Jan-Feb;18(1):56-61.
43. Czasch P, Ilie N. In vitro comparison of mechanical properties and degree of cure of bulk fill composites. Clin Oral Investig. 2013 Jan;17(1):227-35.
44. Mountain G, Wood D, Toumba J. Bite force measurement in children with primary dentition. Int J Paediatr Dent. 2011 Mar;21(2):112-8.
45. Owais AI, Shaweesh M, Abu Alhaija ES. Maximum occusal bite force for children in different dentition stages. Eur J Orthod. 2013 Aug;35(4):427-33.
46. Toz T, Tuncer S, Öztürk Bozkurt F, Kara Tuncer A, Gözükara Bağ H. The effect of bulk-fill flowable composites on the fracture resistance and cuspal deflection of endodontically treated premolars. J Adhes Sci Technol. 2015 Aug;29(15):1581-92.
47. Öztürk-Bozkurt F, Toz-Akalin T, Gözetici B, Kusdemir M, Özsoy A, Gozukara-Bağ H, et al. Load-bearing capacity and failure types of premolars restored with sonic activated bulk-fill-, nano-hybrid and silorane-based resin restorative materials. J Adhes Sci Technol. 2016 Sep;30(17):1880-90.
48. Yasa B, Arslan H, Yasa E, Akcay M, Hatirli H. Effect of novel restorative materials and retention slots on fracture resistance of endodontically-treated teeth. Acta Odontol Scand. 2016 Feb;74(2):96-102.
49. Baghalian A, Ranjpour M, Hooshmand T, Herman N, Ebrahimi A. of fracture resistance in post restorations in primary maxillary incisors. Eur J Paediatr Dent. 2014 Sep;15(3):313-6.
50. Jindal S, Jindal R, Gupta K, Mahajan S, Garg S. Comparative evaluation of the reinforcing effect of different post systems in the restoration of endodontically treated human anterior teeth at two different lengths of post space preparation-an in vitro study. J Dent (Tehran). 2013 Mar;10(2):124-33.
51. Baker L, Moon P, Mourino A. Retention of esthetic veneers on primary stainless steel crowns. ASDC journal of dentistry for children. ASDC J Dent Child. 1996 May-Jun;63(3):185-9.
52. Varvara G, Perinetti G, Di Iorio D, Murmura G, Caputi S. In vitro evaluation of fracture resistance and failure mode of internally restored endodontically treated maxillary incisors with differing heights of residual dentin. J Prosthet Dent. 2007 Nov;98(5):365-72.
53. Heydecke G, Butz F, Hussein A, Strub JR. Fracture strength after dynamic loading of endodontically treated teeth restored with different post-and-core systems. J Prosthet Dent. 2002 Apr;87(4):438-45.
2. Berkowitz RJ. Causes, treatment and prevention of early childhood caries: a microbiologic perspective. J Can Dent Assoc. 2003 May;69(5):304-7.
3. Bayrak S, Tunc ES, Tuloglu N. Polyethylene fiber-reinforced composite resin used as a short post in severely decayed primary anterior teeth: a case report. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 May;107(5):e60-4.
4. Judd PL, Casas MJ. Psychosocial perceptions of premature tooth loss in children. Ont Dent. 1995 Oct;72(8):16-8.
5. Eidelman E, Faibis S, Peretz B. A comparison of restorations for children with early childhood caries treated under general anesthesia or conscious sedation.Pediatr Dent. 2000 Jan-Feb;22(1):33-7.
6. Vargas CM, Ronzio CR. Disparities in early childhood caries.BMC Oral Health. 2006 Jun 15;6 Suppl 1:S3.
7. Holan G, Rahme MA, Ram D. Parents' attitude toward their children's appearance in the case of esthetic defects of the anterior primary teeth. J Clin Pediatr Dent. 2009 Winter;34(2):141-5.
8. Waggoner WF. Restoring primary anterior teeth. Pediatr Dent. 2002 Sep-Oct;24(5):511-6.
9. Memarpour M, Shafiei F, Abbaszadeh M. Retentive strength of different intracanal posts in restorations of anterior primary teeth: an in vitro study. Restor Dent Endod. 2013 Nov;38(4):215-21.
10. Kwon Y, Ferracane J, Lee I-B. Effect of layering methods, composite type, and flowable liner on the polymerization shrinkage stress of light cured composites. Dent Mater. 2012 Jul;28(7):801-9.
11. Park J, Chang J, Ferracane J, Lee IB. How should composite be layered to reduce shrinkage stress: incremental or bulk filling? Dent Mater. 2008 Nov;24(11):1501-5.
12. Soares CJ, Bicalho AA, Tantbirojn D, Versluis A. Polymerization shrinkage stresses in a premolar restored with different composite resins and different incremental techniques. J Adhes Dent. 2013 Aug;15(4):341-50.
13. Abbas G, Fleming G, Harrington E, Shortall A, Burke F. Cuspal movement and microleakage in premolar teeth restored with a packable composite cured in bulk or in increments. J Dent. 2003 Aug;31(6):437-44.
14. Alrahlah A, Silikas N, Watts D. Post-cure depth of cure of bulk fill dental resin-composites. Dent Mater. 2014 Feb;30(2):149-54.
15. Goracci C, Cadenaro M, Fontanive L, Giangrosso G, Juloski J, Vichi A, et al. Polymerization efficiency and flexural strength of low-stress restorative composites. Dent Mater. 2014 Jun;30(6):688-94.
16. Garoushi S, Säilynoja E, Vallittu PK, Lassila L. Physical properties and depth of cure of a new short fiber reinforced composite. Dent Mater. 2013 Aug;29(8):835-41.
17. Van Ende A, Mine A, De Munck J, Poitevin A, Van Meerbeek B. Bonding of low-shrinking composites in high C-factor cavities. J Dent. 2012 Apr;40(4):295-303.
18. Ilie N, Schoner C, Bucher K, Hickel R. An in-vitro assessment of the shear bond strength of bulk-fill resin composites to permanent and deciduous teeth. J Dent. 2014 Jul;42(7):850-5.
19. Bucuta S, Ilie N. Light transmittance and micro-mechanical properties of bulk fill vs. conventional resin based composites. Clin Oral Investig. 2014 Nov;18(8):1991-2000.
20. Ilie N, Bucuta S, Draenert M. Bulk-fill resin-based composites: an in vitro assessment of their mechanical performance. Oper Dent. 2013 Nov-Dec;38(6):618-25.
21. Kim RJ, Kim YJ, Choi NS, Lee IB. Polymerization shrinkage, modulus, and shrinkage stress related to tooth-restoration interfacial debonding in bulk-fill composites. J Dent. 2015 Apr;43(4):430-9.
22. Didem A, Gözde Y, Nurhan Ö. Comparative mechanical properties of bulk-fill resins. J Compos. Mater. 2014 Apr;4(02):117.
23. Eunice C, Margarida A, João CL, Filomena B, Anabela P, Pedro A, et al. 99mTc in the evaluation of microleakage of composite resin restorations with SonicFillTM. An in vitro experimental model. Open J Stomatol. 2012 Oct;2(04):340.
24. Poggio C, Chiesa M, Scribante A, Mekler J, Colombo M. Microleakage in class II composite restorations with margins below the CEJ: in vitro evaluation of different restorative techniques. Med Oral Patol Oral Cir Bucal. 2013 Sep 1;18(5):e793-8.
25. Aminabadi NA, Farahani RM. The efficacy of a modified omega wire extension for the treatment of severely damaged primary anterior teeth. J Clin Pediatr Dent. 2009 Summer;33(4):283-8.
26. Subramaniam P, Girish Babu K, Sunny R. Glass fiber reinforced composite resin as an intracanal post–a clinical study. J Clin Pediatr Dent. 2008 Spring;32(3):207-10.
27. Paryab M, Afshar H, Seraj B, Shakibapoor S, Kharazifard MJ. Fracture strength of severely damaged primary anterior teeth after restoration with composite resin and resin-modified glass ionomer cement. J Islam Dent Assoc Iran 2016 Apr;28(2):57-63.
28. Grewal N, Seth R. Comparative in vivo evaluation of restoring severely mutilated primary anterior teeth with biological post and crown preparation and reinforced composite restoration. J Indian Soc Pedod Prev Dent. 2008 Dec;26(4):141-8.
29. Judd PL, Kenny DJ, Johnston DH, Yacobi R. Composite resin short-post technique for primary anterior teeth. J Am Dent Assoc. 1990 May;120(5):553-5.
30. Seraj B, Ghadimi S, Estaki Z, Fatemi M. Fracture resistance of three different posts in restoration of severely damaged primary anterior teeth: An in vitro study. Dent Res J (Isfahan). 2015 Jul-Aug;12(4):372-8.
31. Magne P, Belser UC. Porcelain versus composite inlays/onlays: effects of mechanical loads on stress distribution, adhesion, and crown flexure. Int J Periodontics Restorative Dent. 2003 Dec;23(6):543-55.
32. Ausiello P, De AG, Rengo S, Davidson C. Fracture resistance of endodontically-treated premolars adhesively restored. Am J Dent. 1997 Oct;10(5):237-41.
33. Atalay C, Yazici A, Horuztepe A, Nagas E, Ertan A, Ozgunaltay G. Fracture resistance of endodontically treated teeth restored with bulk fill, bulk fill flowable, fiber-reinforced, and conventional resin composite. Oper Dent. 2016 Sep-Oct;41(5):E131-40.
34. Galvan RR, West LA, Liewehr FR, Pashley DH. Coronal microleakage of five materials used to create an intracoronal seal in endodontically treated teeth. J Endod. 2002 Feb;28(2):59-61.
35. Gencoglu N, Pekiner FN, Gumru B, Helvacioglu D. Periapical status and quality of root fillings and coronal restorations in an adult Turkish subpopulation. Eur J Dent. 2010 Jan;4(1):17-22.
36. Fathi B, Bahcall J, Maki JS. An in vitro comparison of bacterial leakage of three common restorative materials used as an intracoronal barrier. J Endod. 2007 Jul;33(7):872-4.
37. Carvalho RMd, Pereira JC, Yoshiyama M, Pashley DH. A review of polymerization contraction: The influence of stress development versus stress relief. Oper Dent. 1996 Jan-Feb;21(1):17-24.
38. Pithan S, de Sousa Vieira R, Chain MC. Tensile bond strength of intracanal posts in primary anterior teeth: an in vitro study. J Clin Pediatr Dent. 2002 Fall;27(1):35-9.
39. Isufi A, Plotino G, Grande NM, Ioppolo P, Testarelli L, Bedini R, et al. Fracture resistance of endodontically treated teeth restored with a bulkfill flowable material and a resin composite. Ann Stomatol (Roma). 2016 Jul 19;7(1-2):4-10.
40. Taha N, Maghaireh G, Ghannam A, Palamara J. Effect of bulk-fill base material on fracture strength of root-filled teeth restored with laminate resin composite restorations. J Dent. 2017 Aug;63:60-64.
41. Ilie N, Kessler A, Durner J. Influence of various irradiation processes on the mechanical properties and polymerisation kinetics of bulk-fill resin based composites. J Dent. 2013 Aug;41(8):695-702.
42. Agarwal RS, Hiremath H, Agarwal J, Garg A. Evaluation of cervical marginal and internal adaptation using newer bulk fill composites: An in vitro study. J Conserv Dent. 2015 Jan-Feb;18(1):56-61.
43. Czasch P, Ilie N. In vitro comparison of mechanical properties and degree of cure of bulk fill composites. Clin Oral Investig. 2013 Jan;17(1):227-35.
44. Mountain G, Wood D, Toumba J. Bite force measurement in children with primary dentition. Int J Paediatr Dent. 2011 Mar;21(2):112-8.
45. Owais AI, Shaweesh M, Abu Alhaija ES. Maximum occusal bite force for children in different dentition stages. Eur J Orthod. 2013 Aug;35(4):427-33.
46. Toz T, Tuncer S, Öztürk Bozkurt F, Kara Tuncer A, Gözükara Bağ H. The effect of bulk-fill flowable composites on the fracture resistance and cuspal deflection of endodontically treated premolars. J Adhes Sci Technol. 2015 Aug;29(15):1581-92.
47. Öztürk-Bozkurt F, Toz-Akalin T, Gözetici B, Kusdemir M, Özsoy A, Gozukara-Bağ H, et al. Load-bearing capacity and failure types of premolars restored with sonic activated bulk-fill-, nano-hybrid and silorane-based resin restorative materials. J Adhes Sci Technol. 2016 Sep;30(17):1880-90.
48. Yasa B, Arslan H, Yasa E, Akcay M, Hatirli H. Effect of novel restorative materials and retention slots on fracture resistance of endodontically-treated teeth. Acta Odontol Scand. 2016 Feb;74(2):96-102.
49. Baghalian A, Ranjpour M, Hooshmand T, Herman N, Ebrahimi A. of fracture resistance in post restorations in primary maxillary incisors. Eur J Paediatr Dent. 2014 Sep;15(3):313-6.
50. Jindal S, Jindal R, Gupta K, Mahajan S, Garg S. Comparative evaluation of the reinforcing effect of different post systems in the restoration of endodontically treated human anterior teeth at two different lengths of post space preparation-an in vitro study. J Dent (Tehran). 2013 Mar;10(2):124-33.
51. Baker L, Moon P, Mourino A. Retention of esthetic veneers on primary stainless steel crowns. ASDC journal of dentistry for children. ASDC J Dent Child. 1996 May-Jun;63(3):185-9.
52. Varvara G, Perinetti G, Di Iorio D, Murmura G, Caputi S. In vitro evaluation of fracture resistance and failure mode of internally restored endodontically treated maxillary incisors with differing heights of residual dentin. J Prosthet Dent. 2007 Nov;98(5):365-72.
53. Heydecke G, Butz F, Hussein A, Strub JR. Fracture strength after dynamic loading of endodontically treated teeth restored with different post-and-core systems. J Prosthet Dent. 2002 Apr;87(4):438-45.
| Files | ||
| Issue | Vol 16, No 1 (2019) | |
| Section | Original Article | |
| DOI | https://doi.org/10.18502/fid.v16i1.1112 | |
| Keywords | ||
| Filtek Bulk Fill Composite Resins Tooth Deciduous Dentin | ||
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How to Cite
1.
Mosharrafian S, Shafizadeh M, Sharifi Z. Fracture Resistance of a Bulk-Fill and a Conventional Composite and a Combination of both for Coronal Restoration of Severely Damaged Primary Anterior Teeth. Front Dent. 2019;16(1):69-77.
