Stress Concentration of Endodontically Treated Molars Restored with Transfixed Glass Fiber Post: 3D-Finite Element Analysis

The loss of dental structure caused by endodontic treatment is responsible for a decrease in tooth resistance, which increases susceptibility to fracture. Therefore, it is important that minimally invasive treatments be performed to preserve the dental structure and increase the resistance to fracture of endodontically treated posterior teeth. To evaluate under axial loads, using the finite element method, the stress distribution in endodontically treated molars restored with both transfixed or vertical glass fiber posts (GFP) and resin composite. An endodontically treated molar 3D-model was analyzed using finite element analyses under four different conditions, class II resin composite (G1, control model), vertical glass fiber post (G2), transfixed glass fiber posts (G3) and vertical and transfixed glass fiber posts (G4). Ideal contacts were considered between restoration/resin composite and resin composite/tooth. An axial load (300 N) was applied to the occlusal surface. The resulting tensile stresses were calculated for the enamel and dentin tissue from five different viewports (occlusal, buccal, palatal, mesial and distal views). According to the stress maps, similar stress trends were observed, regardless of the glass fiber post treatment. In addition, for the G1 model (without GFP), a high-stress magnitude can be noticed in the proximal faces of enamel (7.7 to 14 MPa) and dentin (2.1 to 3.3 MPa) tissue. The use of transfixed glass fiber post is not indicated to reduce the stresses, under axial loads, in both enamel and dentin tissue in endodontically treated molar with a class II cavity.

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CAD/CAM Milled Glass Fiber Posts: Adaptation and Mechanical Behavior in Flared Root Canals

Operative Dentistry ◽

10.2341/20-198-l ◽

2021 ◽

Author(s):

MER Gama ◽

GS Balbinot ◽

GC Ferreira ◽

EG Mota ◽

VCB Leitune ◽

...

Keyword(s):

Bond Strength ◽

Glass Fiber ◽

Fiber Post ◽

Root Canals ◽

Fiber Posts ◽

Cad Cam ◽

Glass Fiber Posts ◽

Glass Fiber Post ◽

Post And Core ◽

Push Out

SUMMARY This study aimed to evaluate the cementation and mechanical behavior of flared root canals restored with CAD/CAM milled glass fiber post-and-core systems. Sixty-six endodontically treated human canines with a flared root canal were divided into three different groups according to the type of post: GPF received prefabricated posts; GREL received relined glass fiber posts, and GMILLED received CAD/CAM milled glass fiber posts. Cementation was performed with self-adhesive resin cement. The samples were submitted to x-ray microcomputed tomography analysis for the analysis of voids and gaps. The roots were sectioned and submitted to the push-out bond strength test. The load-to-fracture was evaluated in post-and-core systems. GMILLED presented lower void and lower gap volumes when compared to GPF and GREL. On the load-to-fracture test, GREL presented statistically significant higher values than GMILLED. GPF values had no statistically significant difference from the two other groups. On the push-out bond strength test, GPF presented statistically significant lower values when compared to GREL and GMILLED. The most common failure pattern was between dentin and cement in all groups. CAD/CAM milled glass fiber post-and-core systems presented an enhanced adaptation of glass fiber posts to flared root canal systems. Their results were comparable to relined posts in bond strength, while load-to-fracture-results for GMILLED were lower than those for GPF.

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Stress Generated by Customized Glass Fiber Posts and Other Types by Photoelastic Analysis

Brazilian Dental Journal ◽

10.1590/0103-6440201300256 ◽

2015 ◽

Vol 26 (3) ◽

pp. 222-227 ◽

Cited By ~ 3

Author(s):

Kátia Bosso ◽

Alcides Gonini Júnior ◽

Ricardo Danil Guiraldo ◽

Sandrine Bittencourt Berger ◽

Murilo Baena Lopes

Keyword(s):

Glass Fiber ◽

High Stress ◽

Resin Cement ◽

Fiber Post ◽

Tooth Structure ◽

Biomechanical Behavior ◽

Fiber Posts ◽

Glass Fiber Posts ◽

Glass Fiber Post ◽

Post And Core

Endodontic posts are necessary to provide adequate retention and support when no sufficient remaining structure is available to retain the core. There are different materials and techniques to construct post-and-core, but there is no consensus about which one promotes better stress distribution on the remaining tooth structure. This study aimed to quantify and evaluate the distribution of stress in the root produced by customized glass fiber posts compared to different endodontic posts. Twenty-five simulated roots from photoelastic resin were made and divided into 5 groups: CPC, cast post-and-core; SP, screw post; CF, carbon fiber post; GF, glass fiber post; and CGF, customized glass fiber post. After cementing CPC and SP posts with zinc phosphate cement, and CF, GF and CGF posts with resin cement, resin cores were made for groups 2-5. Specimens were evaluated with vertical or 45° oblique loading. To analyze the fringes, the root was divided into 6 parts: palatal cervical, palatal middle, palatal apical, vestibular cervical, vestibular middle, and vestibular apical. The formed fringes were photographed and quantified. Data were recorded and subjected to two-way ANOVA and Tukey's test (5%). SP (1.95±0.60) showed higher stress (p<0.05) compared to the others (CPC-0.52±0.74; CF-0.50±0.75, GF-0.23±0.48 and CGF-0.45±0.83). All posts showed high stress in apical third (CPC-1.40±0.65; SP-2.30±0.44, CF-1.80±0.45, GF-1.20±0.45, CGF-1.70±1.03) Low stress was found in cervical third (CPC-0.20±0.45; CF-0.00±0.00, GF-0.00±0.00, CGF-0.00±0.00), except by SP (1.90±0.65), which showed statistical difference (p<0.05). Customized post showed high stress concentration at the root and conventional glass fiber posts showed more favorable biomechanical behavior.

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Fracture Resistance of Simulated Immature Teeth after Different Intra-radicular Treatments

Brazilian Dental Journal ◽

10.1590/0103-6440201300186 ◽

2015 ◽

Vol 26 (3) ◽

pp. 211-215 ◽

Cited By ~ 7

Author(s):

Gustavo Sivieri-Araujo ◽

Mario Tanomaru-Filho ◽

Juliane Maria Guerreiro-Tanomaru ◽

Eduardo Antunes Bortoluzzi ◽

Érica Gouveia Jorge ◽

...

Keyword(s):

Glass Fiber ◽

Fracture Strength ◽

Root Canal ◽

Fracture Resistance ◽

Testing Machine ◽

Fiber Post ◽

Immature Teeth ◽

Fiber Posts ◽

Glass Fiber Posts ◽

Glass Fiber Post

The aim of this study was to evaluate the fracture resistance of simulated immature teeth after different intra-radicular treatments. Crowns and roots of bovine incisors were cut transversally and removed to simulate immature teeth. Root canal preparation and flaring were performed using a bur in crown-apex and apex-crown direction. The samples were distributed into 5 groups (n=10): Positive control (PoC) - no root canal flaring or filling; Negative control (NeC) - teeth were sectioned and their root canals were flared; Direct anatomical glass fiber post (RaP) - #2 Reforpost main glass fiber post relined with composite resin; Double tapered conical glass fiber posts (ExP) - #3 Exacto glass fiber post; and #2 Reforpost main glass fiber + Reforpin accessory glass fiber posts (RrP). In RaP, ExP and RrP, 4.0-mm apical plugs were done with MTA Angelus. The specimens were embedded in polystyrene resin inside cylinders and the periodontal ligament was simulated with a polyether-based impression material. The specimens were submitted to compressive fracture strength test (0.5 mm/min at 135° relative to the long axis of the tooth) in a servo-hydraulic mechanical testing machine MTS 810. Data were subjected to one-way ANOVA and Dunnett's C or Tukey's tests (α=0.05). The control groups (PoC and NeC) showed lower fracture strength than the experimental groups. NeC presented the lowest resistance and ExP presented the highest resistance among the experimental groups. The flaring procedures produced a detrimental effect on the fracture resistance of the bovine teeth. Glass fiber intra-radicular posts increased significantly the fracture resistance of simulated immature teeth.

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Push-out bond strength of glass fiber posts luted with two resin cements

Brazilian Dental Science ◽

10.14295/bds.2017.v20i4.1452 ◽

2017 ◽

Vol 20 (4) ◽

pp. 78

Author(s):

Blanca Liliana Torres Léon ◽

Vitor Lopes Franco ◽

Emily Vivianne Freitas Silva ◽

Leonardo Muniz ◽

Fernando Carneiro Ribeiro

Keyword(s):

Bond Strength ◽

Glass Fiber ◽

Fiber Post ◽

Resin Cements ◽

Anterior Teeth ◽

Fiber Posts ◽

Post And Core Technique ◽

Glass Fiber Posts ◽

Glass Fiber Post ◽

Push Out

Objective. To evaluate the bond strength of a prefabricated glass fiber post to the root dentin with two resin cements using the push-out test. Material and Methods. Thirty fiber posts (White Post ECD) were cemented in human endodontically treated anterior teeth with two resin cements (n=15): RelyxTM ARC and AllCem. The roots were transversely sectioned and divided in cervical, middle and apical thirds after 48 h of cementation. The specimens' retention was tested by push-out method. The results were analyzed by 2-way ANOVA and Tukey’s test (p<0.05). Results. There were no significant differences in the bond strength between the resin cements. The bond strength was higher in cervical third than in middle and apical thirds for both resin cements. It was observed higher percentages of adhesive failures followed by mixed. Conclusions. Both resin cements are indicated in the cementation of glass fiber post.KeywordsDental prosthesis; Post and core technique; Biomechanical phenomena.

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Better Glass-fiber Post Preservation in Teeth with Ferrule When Subjected to Chewing

Operative Dentistry ◽

10.2341/20-186-l ◽

2021 ◽

Author(s):

CP Gré ◽

DP Lise ◽

RQ Ramos ◽

B Van Meerbeck ◽

LCC Vieira ◽

...

Keyword(s):

Glass Fiber ◽

Failure Modes ◽

Acrylic Resin ◽

Fiber Post ◽

Composite Cement ◽

Mechanical Fatigue ◽

Fiber Posts ◽

Glass Fiber Posts ◽

Glass Fiber Post ◽

Post Hoc

SUMMARY Objectives: To evaluate the influence of ferrule effect and mechanical fatigue aging on glass-fiber post push-out bond strength (PBS) to root-canal dentin at different root thirds of premolars. Methods and Materials: Thirty-two sound maxillary premolar teeth were collected, and randomly assigned to two experimental groups (n=16): ‘Remaining Dentin Ferrule’ (RDF) = coronal crown cut 2.0 mm above the cemento-enamel junction (CEJ); ‘Without Dentin Ferrule’ (WDF) = coronal crown cut at the cemento-enamel junction. Teeth were endodontically treated, post spaces were prepared up to 10.0-mm depth from CEJ, and glass-fiber posts were cemented using a dual-cure self-adhesive composite cement. Standardized cores were built using a light-cure composite, upon which tooth cores were prepared using a 1.5-mm taper ogival-end diamond bur. Crowns were handmade using self-cure acrylic resin and cemented using the aforementioned composite cement. Half of the specimens were subjected to 1,200,000 cycles of mechanical fatigue in a chewing simulator (F = ‘Fatigue’), while the other half were stored in distilled water at 37°C for 1 week (C = ‘Control’). All specimens were horizontally sectioned into 1.0-mm thick slices prior to PBS test; the failure modes were assessed using stereomicroscopy and scanning electron microscopy (SEM). Data were analyzed for each root third using two-way analysis of variance (ANOVA) followed by Tukey HSD post-hoc test; frequency distribution was compared by Chi-square test (α=0.05) and post-hoc comparisons with Bonferroni. Results: The mean PBS in MPa (SD) were = RDF_F = 10.4 (2.9); WDF_F = 6.9 (1.7); RDF_C = 14.5 (2.7); WDF_C = 14.2 (2.9). Similar PBS were found for the root thirds. For all root thirds, significant differences were found for both the factors Dentin Ferrule and Fatigue, and their interaction (p<0.05). The lowest PBS was found for specimens without dentin ferrule subjected to chewing fatigue (p<0.001). Most failures occurred at the composite cement/dentin interface, followed by mixed and composite cement/glass-fiber post interfacial failures. There was a significant increase in mixed failures for the WDF_F group (p<0.001). Conclusion: Absence of 2.0-mm remaining dentin ferrule in premolars resulted in a higher decrease of the glass-fiber posts’ PBS to dentin after mechanical fatigue, irrespective of root third.

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Fracture Resistance of Three Post Types in the Restoration of Anterior Primary Teeth

The Open Dentistry Journal ◽

10.2174/1874210602014010375 ◽

2020 ◽

Vol 14 (1) ◽

pp. 375-383

Author(s):

Fatemeh Kadkhodaei ◽

Majid Mehran ◽

Roza Haghgoo ◽

Mehrshad Zareiyan

Keyword(s):

Glass Fiber ◽

Fracture Resistance ◽

Primary Teeth ◽

Composite Resin ◽

Pediatric Dentistry ◽

Fiber Post ◽

Anterior Teeth ◽

Fiber Posts ◽

Glass Fiber Posts ◽

Glass Fiber Post

Background: Extensive restorative treatments of anterior primary teeth are challenging in pediatric dentistry. Objective: This study aimed to compare the fracture resistance of three post types for restoring the anterior primary teeth. Methods: This in-vitro study was carried out on 90 extracted maxillary anterior primary teeth with intact roots. They were randomly allocated into six groups to be restored with conventional composite resin post, X-tra fill composite resin post, Tetric N Ceram composite resin post, prefabricated glass fiber post with conventional composite build-up, prefabricated glass fiber post with X-tra fill composite build-up, and prefabricated glass fiber post with Tetric N Ceram composite build up. The samples were polished and placed in acrylic resin blocks with 1 mm of part of cervical root being out, thermocycled (×5000) and tested for fracture resistance. Intra-class correlation test, Kruskal-Wallis test and one-way ANOVA were used for statistical analyses (α=0.05). Results: The mean fracture resistance was significantly different among the six groups. It was the highest in prefabricated glass fiber post with conventional composite build-up (418.64 N), prefabricated glass fiber post with X-tra fill composite build-up (403.63 N) and prefabricated glass fiber post with Tetric N Ceram composite build up (361.63 N); and the lowest in Tetric N Ceram group (280.65 N). The groups were significantly different concerning the fracture strength and fracture state. Conclusion: Since the anterior teeth restored with prefabricated glass fiber posts were far more fracture resistant, and prefabricated glass fiber posts can be promisingly used for the restoration of anterior primary teeth.

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Influence of Post and Resin Cement on Stress Distribution of Maxillary Central Incisors Restored with Direct Resin Composite

Operative Dentistry ◽

10.2341/08-73 ◽

2009 ◽

Vol 34 (2) ◽

pp. 223-229 ◽

Cited By ~ 39

Author(s):

A. O. Spazzin ◽

D. Galafassi ◽

A. D. de Meira-Júnior ◽

R. Braz ◽

C. A. Garbin

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Elastic Modulus ◽

Resin Composite ◽

Resin Cement ◽

Zirconia Ceramic ◽

Element Analysis ◽

Fiber Posts ◽

Stress Levels ◽

Glass Fiber Posts

Clinical Relevance According to finite element analysis, the zirconia ceramic post created higher stress levels in the post and slightly less in dentin compared with glass fiber posts. Resin cement with a high elastic modulus created higher stress levels in the cement layer. The different film thicknesses of cement did not create significant changes in stress levels.

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A comparative study of stress distribution between glass fiber post and cast post in an endodontically treated central incisor – A finite element analysis

Journal of Interdisciplinary Dentistry ◽

10.4103/jid.jid_35_19 ◽

2019 ◽

Vol 9 (3) ◽

pp. 108

Author(s):

Padmashini Gnanam ◽

N Vignesh ◽

S Lakshmi ◽

H Annapoorani

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Distribution ◽

Comparative Study ◽

Glass Fiber ◽

Central Incisor ◽

Fiber Post ◽

Element Analysis ◽

Glass Fiber Post

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Influence of the Resin Cement Thickness on the Push-Out Bond Strength of Glass Fiber Posts

Brazilian Dental Journal ◽

10.1590/0103-6440201600886 ◽

2016 ◽

Vol 27 (5) ◽

pp. 592-598 ◽

Cited By ~ 7

Author(s):

Regina Maria Helen-Cot Marcos ◽

◽

Gustavo Ross Kinder ◽

Edson Alfredo ◽

Tarcisio Quaranta ◽

...

Keyword(s):

Bond Strength ◽

Glass Fiber ◽

Resin Composite ◽

Resin Cement ◽

Distilled Water ◽

Cement Layer ◽

Fiber Posts ◽

Glass Fiber Posts ◽

Post Space ◽

Push Out

Abstract The objective of the present study was to evaluate the influence of resin cement thickness on the bond strength of prefabricated and customized glass fiber posts after storage in distilled water. Thirty human uniradicular roots were treated endodontically. The roots were divided into 3 groups: THIN (thin cement layer) - post space preparation with #0.5 drill and cementation of #0.5 post; THICK (thick cement layer) - post space preparation with #1 drill and cementation of #0.5 post; and CUSTOM (customized cement layer) - post space preparation with #1 drill and cementation of a customized post (#0.5 glass fiber posts customized with resin composite). All posts were luted with self-adhesive resin cement. The push-out test was carried out after storage for 24 h and 90 days in distilled water at 37 °C. The data were analyzed with three-way ANOVA and Tukey's test (a=0.05). Bond strengths were significantly higher for CUSTOM (9.37 MPa), than for THIN (7.85 MPa) and THICK (7.07 MPa), which were statistically similar. Considering the thirds, the bond strength varied in the sequence: apical (7.13 MPa) < middle (8.22 MPa) = coronal (8.94 MPa). Bond strength for 24 h storage was significantly higher (8.80 MPa) than for 90-day storage (7.40 MPa). It may be concluded that the thickness of resin cement influenced the bond strength of glass fiber posts. The customized posts presented higher bond strength. Storage in water for 90 days affected negatively the values of bond strength, especially for thick cement layers in the apical third.

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