Stress Analysis on Mesiolingual Cavity of Endodontically Treated Molar Restored Using Bidirectional Fiber-Reinforced Composite (Wallpapering Technique)

Figures & data

Figure 1 (A) Non cuspal coverage and (B) cuspal coverage cavity design.

Figure 2 Components of 3D direct restoration reinforced fiber composite (A) non-cuspal coverage and (B) cuspal coverage.

Table 1 The Criteria of Cavity Design

Non-Cuspal Coverage	Cuspal Coverage
Buccal wall thickness > 2mm Distal wall thickness > 2mm The lingual ferrule is 2 mm above the CEJ The mesial ferrule is 2 mm above the CEJ Cavo surface line angles rounded The external walls form a 90° angle	Cusp reduction is 1.5 mm The finish line on the buccal is hollow chamfer and the butt joint on distal Buccal wall thickness > 2mm Distal wall thickness > 2mm The lingual ferrule is 2 mm above the CEJ The mesial ferrule is 2 mm above the CEJ Cavo surface line angles were rounded The external walls form a 90° angle

Table 2 Placement of the Restoration Materials on the Molar Cavity Without Mesiolingual Walls

Non Cuspal Coverage Restoration

Cuspal Coverage Restoration

Build lingual and mesial walls using packable composite Positioned the bidirectional fiber at the cavity floor following the contour of the base and circumferentially surrounded the axial wall Place flowable composites on the bidirectional fibers to the cavity walls Packable composite filled the inside of the entire cavity

Build lingual and mesial walls using packable composite Positioned the bidirectional fiber at the cavity floor following the contour of the base and circumferentially surrounded the axial wall Place flowable composites on the bidirectional fibers to the cavity walls Packable composite filled the inside of the cavity Place the bidirectional fiber on the occlusal part and build the cusp using packable composite.

Table 3 Mechanical Properties of Tooth and Materials Restoration

Materials Component	Modulus Elasticity (GPa)	Poisson’s Ratio
Enamel^Citation14	50.2	0.30
Dentin^Citation15	17.8	0.31
Periodontal ligament^Citation14	0.05	0.45
Gutta percha^Citation16	0.069	0.45
Alveolar bone^Citation16	11.5	0.30
Cancellous bone^Citation17	1.37	0.30
Polyethylene Fiber (Ribbon THM)^Citation18	23.6	0.32
E-Glass Fiber Bidirectional (Everstick Net)^Citation9	8.87	0.35
Packable composite resin (Grandio, VOCO)^Citation19	20.4	0.33
Flowable composite resin (Gaenial Universal Flow, GC)^Citation20	7.9	0.30
SDR^Citation21	8.6	0.30

Table 4 The Strength Properties of Adhesive Material

Properties	Part of Component	Strength
Tensile bond strength	Dentin – polyethylene fiber^Citation22	28.3 MPa
	Dentin - E-glass fiber^Citation23	27.9 MPa
Shear bond strength	Dentin – polyethylene fiber^Citation24	25.92 MPa
	Dentin - E-glass fiber^Citation24	28.05 MPa
	Enamel – polyethylene fiber^Citation24	29.08 MPa
	Enamel - E-glass fiber^Citation24	39.87 MPa

Figure 3 The loading zone (A) vertical force and (B) oblique force are represented by the red region.

Table 5 Maximum and Minimum Principal Stress on Non-Cuspal Coverage Restoration Used Polyethylene Fiber

Tooth and Restoration Component	Strength		Vertical Force		Oblique Force 45°
	Tensile	Compressive	Max. Princ. Stress (MPa)	Min. Princ Stress (MPa)	Max. Princ. Stress (MPa)	Min. Princ. Stress (MPa)
Enamel	40.1 MPa^Citation26	261 MPa^Citation26	32.7	−152.9	39	−73
Dentin	49.8 MPa^Citation26	233.5 MPa^Citation26	40.6	−78.8	37	−48
Composite	72 MPa^Citation27	439 MPa^Citation27	39.4	−85.1	55	−80
Cir. Fiber	49.43 MPa^Citation28	190.47 MPa^Citation29	19.8	−48.5	18	−19
Base Fiber	49.43 MPa^Citation28	190.47 MPa^Citation29	26.9	−29.3	22	−27

Abbreviations: Max. Princ, Maximum Principal; Min. Princ, Minimum Principal; Cir, Circumferential.

Table 6 Maximum and Minimum Principal Stress on Non-Cuspal Coverage Restoration Using e-Glass Fiber

Tooth and Restoration Component	Strength		Vertical Force		Oblique Force 45°
	Tensile	Compressive	Max. Princ. Stress (MPa)	Min. Princ. Stress (MPa)	Max. Princ. Stress (MPa)	Min. Princ. Stress (MPa)
Enamel	40.1 MPa^Citation26	261 MPa^Citation26	29.8	−144.9	34.1	−99.6
Dentin	49.8 MPa^Citation26	233.5 MPa^Citation26	39.8	−95.3	36.6	−48
Composite	72 MPa^Citation27	439 MPa^Citation27	68.3	−112.2	55.8	−100.1
Cir. Fiber	26.6 MPa^Citation30	90.32 MPa^Citation31	38.1	−28.5	21.1	−19.5
Base Fiber	26.6 MPa^Citation30	90.32 MPa^Citation31	31.9	−139.4	51.9	−74.6

Abbreviations: Max. Princ, Maximum Principal; Min. Princ, Minimum Principal; Cir, Circumferential, italic font means the stress exceed the maximum material strength.

Table 7 Maximum and Minimum Principal Stress on Cuspal Coverage Restoration Used Polyethylene Fiber

Tooth and Restoration Component	Strength		Vertical Force		Oblique Force 45°
	Tensile	Compressive	Max. Princ. Stress (MPa)	Min. Princ Stress (MPa)	Max. Princ. Stress (MPa)	Min. Princ. Stress (MPa)
Enamel	40.1 MPa^Citation26	261 MPa^Citation26	20.03	−97	24.6	−48.27
Dentin	49.8 MPa^Citation26	233.5 MPa^Citation26	38.96	−76.29	33.8	−44.9
Composite	72 MPa^Citation27	439 MPa^Citation27	56.92	−181.43	60.5	−81
Cir. Fiber	49.43 MPa^Citation28	190.47 MPa^Citation29	17.25	−47.90	21	−19
Base Fiber	49.43 MPa^Citation28	190.47 MPa^Citation29	37.21	−83.83	21.9	−32.7
Occ. Fiber	49.43 MPa^Citation28	190.47 MPa^Citation29	27.89	−42.33	27.9	−28.8

Abbreviations: Max. Princ, Maximum Principal; Min. Princ, Minimum Principal; Cir, Circumferential; Occ, Occlusal.

Table 8 Maximum and Minimum Principal Stress on Cuspal Coverage Restoration Using e-Glass Fiber

Tooth and Restoration Component	Strength		Vertical Force		Oblique Force 45°
	Tensile	Compressive	Max. Princ. Stress (MPa)	Min. Princ Stress (MPa)	Max. Princ. Stress (MPa)	Min. Princ. Stress (MPa)
Enamel	40.1 MPa^Citation26	261 MPa^Citation26	20.5	−89.8	24.89	−48.27
Dentin	49.8 MPa^Citation26	233.5 MPa^Citation26	39.4	−95.4	33.47	−48.27
Composite	72 MPa^Citation27	439 MPa^Citation27	70.8	−221.7	57.73	−91.05
Cir. Fiber	26.6 MPa^Citation30	90.32 MPa^Citation31	19.9	−31.7	20.39	−19.9
Base Fiber	26.6 MPa^Citation30	90.32 MPa^Citation31	26.3	−199.8	51.64	−63.05
Occ. Fiber	26.6 MPa^Citation30	90.32 MPa^Citation31	15.4	−58.3	11.29	−28.65

Abbreviations: Max. Princ, Maximum Principal; Min. Princ, Minimum Principal; Cir, Circumferential; Occ, Occlusal, italic font means the stress exceed the maximum material strength.

Figure 4 The black dashed circles is the location of high-stress concentration on a fiber-reinforced composite of polyethylene non-cuspal coverage (PNCC). The red area is the maximum principal stress on the surface of the restoration when a vertical force (above) and an oblique force (below). The blue area is the minimum principal stress on the surface of the restoration when a vertical (above) and an oblique force (below).

Figure 5 The black dashed circles is the location of high-stress concentration on a fiber-reinforced composite of e-glass fiber non-cuspal coverage (ENCC). The red area is the maximum principal stress on the surface of the restoration when a vertical force (above) and an oblique force (below). The blue area is the minimum principal stress on the surface of the restoration when a vertical (above) and an oblique force (below).

Figure 6 The black dashed circles is the location of high-stress concentration on a fiber-reinforced composite of polyethylene cuspal coverage (PCC). The red area is the maximum principal stress on the surface of the restoration when a vertical force (above) and an oblique force (below). The blue area is the minimum principal stress on the surface of the restoration when a vertical (above) and an oblique force (below).

Figure 7 The black dashed circles is the location of high-stress concentration on a fiber reinforced composite of e-glass fiber cuspal coverage (ECC). The red area is the maximum principal stress on the surface of the restoration when a vertical force (above) and an oblique force (below). The blue area is the minimum principal stress on the surface of the restoration when a vertical (above) and an oblique force (below).

Figure 8 Shows where high-stress concentrations are found on the PNCC interfacial surface. The restoration underwent a debonding initiation, as indicated by the dashed black circle, wherein the contact stress ratio reached a value of 1 at the enamel fissure.

Figure 9 Shows where high-stress concentrations are found on the ENCC interfacial surface. The restoration underwent a debonding initiation, as indicated with the dashed black circle, wherein the contact stress ratio reached a value of 1 at the distal region on the base fiber.

Figure 10 Shows where high-stress concentrations are found on the PCC interfacial surface. The restoration underwent a debonding initiation, as indicated with the dashed black circle, wherein the contact stress ratio reached a value of 1 at the fiber occlusal between the enamel and the restoration.

Figure 11 Shows where high-stress concentrations are found on the ECC interfacial surface. The restoration underwent a debonding initiation, as indicated with the dashed black circle, wherein the contact stress ratio reached a value of 1 at the distal region on the base fiber.

Table 9 The Initiation Damage Criterion

The Interfaces	Vertical Force				Oblique Force 45°
	PNCC	ENCC	PCC	ECC	PNCC	ENCC	PCC	ECC
Enamel-composite	1.6	1.5	1.01	0.9	1.7	1.8	0.1	0.2
Enamel-fiber	–	–	0.37	0.2	–	–	0.2	0.25
Dentin-composite	0.2	0.7	0.82	0.8	0.2	0.2	0.2	0.2
Dentin-fiber circumferential	0.8	2.8	0.64	0.67	0.5	0.8	0.5	0.84
Dentin-fiber alas	0.5	5.4	0.49	7.1	0.5	6.2	0.5	5.06

Abbreviations: PNCC, polyethylene non-cuspal coverage; ENCC, e-glass non-cuspal coverage; PCC, polyethylene cuspal coverage; ECC, e-glass cuspal coverage, italic font means debonding occurred between tooth and material.

Barcelos LM, Bicalho AA, Veríssimo C, Rodrigues MP, Soares CJ. Stress distribution, tooth remaining strain, and fracture resistance of endodontically treated molars restored without or with one or two fiberglass posts and direct composite resin. Oper Dent. 2017;42(6):646–657. doi:10.2341/16-224-L

 PubMed Web of Science ®Google Scholar

Cheron RA, Marshall SJ, Goodis HE, Peters OA. Nanomechanical properties of endodontically treated teeth. J Endod. 2011;37(11):1562–1565. doi:10.1016/j.joen.2011.08.006

 PubMed Web of Science ®Google Scholar

Elkholy MMA, Nawar NN, Ha WN, Saber SM, Kim HC. Impact of canal taper and access cavity design on the life span of an endodontically treated mandibular molar: a finite element analysis. J Endod. 2021;47(9):1472–1480. doi:10.1016/j.joen.2021.06.009

 PubMed Web of Science ®Google Scholar

Navimipour EJ, Firouzmandi M, Mirhashemi FS. Finite element analysis of the endodontically-treated maxillary premolars restored with composite resin along with glass fiber insertion in various positions. J Contemp Dent Pract. 2015;16(4):284–290. doi:10.5005/jp-journals-10024-1677

 PubMedGoogle Scholar

Asopa S, Mandava J, Chalasani U, Anwarullah A, Ravi R. Fracture resistance of endodontically treated molars restored with resin composites. Indian J Conserv Endod. 2017;2(3):89–97.

 Google Scholar

Lukarcanin J, Sadikoǧlu İS, Yaşa B, Türkün LŞ, Türkün M. Comparison of different restoration techniques for endodontically treated teeth. Int J Biomater. 2022;2022. doi:10.1155/2022/6643825

 PubMed Web of Science ®Google Scholar

Halaçoglu DM, Yamanel K. The effects of different base materials on the stress distribution of the endodontically treated teeth: 3D FEA. Cumhur Dent J. 2019;22(1):56–65. doi:10.7126/cumudj.453467

 Google Scholar

Prabhakar A, Shrikant L, Nadig B. Stress analysis in maxillary incisor following fragment reattachment: a finite element analysis. J Dent Allied Sci. 2016;5(1):7. doi:10.4103/2277-4696.185188

 Google Scholar

Rizzante FAP, Mondelli RFL, Furuse AY, Borges AFS, Mendonça G, Ishikiriama SK. Shrinkage stress and elastic modulus assessment of bulk-fill composites. J Appl Oral Sci. 2019;27:1–9. doi:10.1590/1678-7757-2018-0132

 Web of Science ®Google Scholar

Sadr A, Bakhtiari B, Hayashi J, et al. Effects of fiber reinforcement on adaptation and bond strength of a bulk-fill composite in deep preparations. Dent Mater. 2020;36(4):527–534. doi:10.1016/j.dental.2020.01.007

 PubMed Web of Science ®Google Scholar

Tezvergil-Mutluay A, Lassila LVJ, Vallittu PK. Microtensile bond strength of fiber-reinforced composite with semi-interpenetrating polymer matrix to dentin using various bonding systems. Dent Mater J. 2008;27(6):821–826. doi:10.4012/dmj.27.821

 PubMed Web of Science ®Google Scholar

Ilday N, Seven N. The influence of different fiber-reinforced composites on shear bond strengths when bonded to enamel and dentin structures. J Dent Sci. 2011;6(2):107–115. doi:10.1016/j.jds.2011.03.008

 Web of Science ®Google Scholar

Perdigão J. Restoration of root canal-treated teeth; 2016.

 Google Scholar

GrandioSo, Voco.Scientific compendium. 2017.

 Google Scholar

Hasanah, Prihashinta Uswatun, Purwanto Agustiono, Widjijono Widgijono. Comparison of traction strength between fiber and braided fiber on fiber reinforced composite type ultrahigh molecular weight polyethelene (uhmwpe). 2018;3(1):18–21.

 Google Scholar

Afifa Zahratu Firda D. Impact of fiber braided polyethylene application on composite nanofil resin pressure strength. PhD Thesis. Muhammadiyah University Surakarta. 2016.

 Google Scholar

Rosyida NF, Sunarintyas S, Pudyani PS. The effect of silanated and impregnated fiber on the tensile strength of E-glass fiber reinforced composite retainer. Dent J. 2015;48(1):22. doi:10.20473/j.djmkg.v48.i1.p22-25

 Google Scholar

Mangoush E, Säilynoja E, Prinssi R, Lassila L, Vallittu PK, Garoushi S. Comparative evaluation between glass and polyethylene fiber reinforced composites: a review of the current literature. J Clin Exp Dent. 2017;9(12):1408–1417.

 Google Scholar