Evaluation of the Fracture Resistance of Roots Obturated with Bioceramic-Based Root Canal Sealer and Two Different Techniques
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2025-04-20 |
| Journal | Current Research in Dental Sciences |
| Authors | Salih DĂŒzgĂŒn, HĂŒseyin Sinan TopçuoÄlu, Ä°pek Eraslan AkyĂŒz |
| Institutions | Bozok Universitesi |
| Analysis | Full AI Review Included |
Evaluation of the Fracture Resistance of Roots Obturated with Bioceramic-Based Root Canal Sealer
Section titled âEvaluation of the Fracture Resistance of Roots Obturated with Bioceramic-Based Root Canal SealerâThis analysis evaluates the mechanical performance and fracture resistance (FR) of root-filled teeth, comparing two distinct sealer chemistries (Bioceramic vs. Epoxy Resin) and two common obturation techniques (Single Cone vs. Cold Lateral Compaction).
Executive Summary
Section titled âExecutive Summaryâ- Objective: To determine if the choice of root canal sealer (Ceraseal [CS] or AH Plus Jet [AHPJ]) or filling technique (Single Cone Technique [SCT] or Cold Lateral Compaction Technique [CLCT]) significantly affects the vertical fracture resistance (FR) of prepared roots.
- Key Finding (Preparation Effect): Root canal preparation (instrumentation) was the dominant factor influencing structural integrity. Prepared, unfilled roots (Positive Control) exhibited significantly less FR (254.56 N) than unprepared, unfilled roots (Negative Control, 672.84 N) (P<.05).
- Key Finding (Material/Technique Effect): There was no statistically significant difference in fracture resistance among the four experimental groups utilizing different sealer/technique combinations (P>.05).
- Performance Range: The mean FR for all filled groups clustered tightly, ranging from 427.96 N (AHPJ + CLCT) to 457.12 N (CS + SCT).
- Conclusion: The null hypothesis was accepted: the fracture resistance of roots filled with modern sealers is independent of whether a bioceramic (CS) or epoxy resin (AHPJ) sealer is used, or whether the SCT or CLCT technique is employed.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Sample Type | Mandibular Premolars | N=90 | Single-rooted, extracted for periodontal reasons |
| Standard Root Length | 13 | mm | Length after crown removal |
| Final Preparation Size | ProTaper F3 | N/A | Standardized instrumentation |
| Irrigation Solution 1 | 2.5% NaOCl | 3 mL | Used between file changes |
| Smear Layer Removal | 17% EDTA | 2 mL for 3 min | Followed by distilled water rinse |
| Sealer 1 (Bioceramic) | Ceraseal (CS) | N/A | Calcium silicate-based sealer |
| Sealer 2 (Epoxy Resin) | AH Plus Jet (AHPJ) | N/A | Gold standard epoxy resin-based sealer |
| Embedded Length | 4 | mm | Embedded in self-cure acrylic resin |
| Compressive Load Rate | 1 | mm/min | Applied via Universal Test Machine |
| Negative Control FR | 672.84 ± 181.37 | N | Unprepared, unfilled (Highest FR) |
| Positive Control FR | 254.56 ± 86.41 | N | Prepared, unfilled (Lowest FR) |
| CS + SCT FR | 457.12 ± 96.48 | N | Highest FR among filled groups |
| AHPJ + CLCT FR | 427.96 ± 84.12 | N | Lowest FR among filled groups |
Key Methodologies
Section titled âKey Methodologiesâ-
Sample Preparation and Standardization:
- 90 single-rooted mandibular premolars were selected.
- Crowns were removed using a water-cooled diamond saw to achieve a standardized root length of 13 mm.
- Teeth exhibiting mesiodistal or buccolingual diameters deviating >20% from the mean were excluded to ensure dimensional consistency.
-
Working Length (WL) and Instrumentation:
- WL was established 1 mm short of the apical foramen.
- Root canals (excluding the negative control group) were prepared up to the ProTaper F3 file using a torque-controlled endodontic motor.
-
Irrigation Protocol:
- 3 mL of 2.5% Sodium Hypochlorite (NaOCl) was used for irrigation between each file.
- Smear layer was removed using 2 mL of 17% EDTA for 3 minutes, followed by a final rinse with distilled water.
-
Obturation Techniques (Groups 3-6):
- Single Cone Technique (SCT): A master F3 gutta-percha cone with good tug-back was selected. Sealer (CS or AHPJ) was placed 2 mm coronal to the WL and withdrawn slowly, followed by placement of the master cone.
- Cold Lateral Compaction Technique (CLCT): A 0.02/30 master gutta-percha cone was fitted. Sealer (CS or AHPJ) was placed via a lentulo spiral. Accessory cones coated with sealer were compacted using a size 25 finger spreader until the spreader could not penetrate 2 mm short of the WL.
-
Fracture Resistance Testing:
- Roots were embedded 4 mm into self-cure acrylic resin blocks, leaving 9 mm exposed.
- A vertical compressive load was applied to the center of the canal opening using a 3 mm rounded steel tip on a universal test machine.
- The load was applied at a rate of 1 mm/min until catastrophic fracture occurred, and the maximum force (N) was recorded.
Commercial Applications
Section titled âCommercial ApplicationsâThis research provides critical material science data relevant to the development and clinical application of endodontic biomaterials and instrumentation protocols.
- Biomaterial Validation: Confirms the mechanical equivalence of newer Calcium Silicate-based sealers (CS) compared to established Epoxy Resin sealers (AHPJ) in reinforcing dentin structure against vertical fracture. This supports the commercial viability of CS sealers.
- Medical Device Optimization (Ni-Ti Files): The finding that preparation itself causes the largest drop in FR highlights the need for endodontic file manufacturers to optimize file taper and cutting geometry to minimize dentin removal while achieving adequate cleaning.
- Clinical Efficiency and Protocol Design: Since SCT (a faster, simpler technique) provided equivalent fracture resistance to CLCT (a more complex, time-consuming technique), this supports the adoption of SCT in clinical practice when using modern, high-performance sealers.
- Dentin Reinforcement Products: Provides baseline mechanical data for evaluating future root canal filling materials designed specifically to increase the modulus of elasticity and bonding strength to dentin, thereby mitigating the risk of Vertical Root Fracture (VRF).
View Original Abstract
Objective: The aim of this study was to evaluate the fracture resistance (FR) of the teeth that had been filled using two different root canal-filling techniques and root canal sealers. Methods: Ninety single-rooted lower premolars, extracted for periodontal reasons, were selected. The crowns of the teeth were removed with diamond saw to obtain a root length of 13 mm. The working length of the teeth, excluding the negative control group, was advanced until the number 10 K-file inserted into the root canal was visible through the apical orifice, and the working length was measured to be 1 mm less than the visible length. The teeth were divided into 6 different groups (n=15). Group 1: unprepared and unfilled (negative control), Group 2: prepared and unfilled (positive control): Group 3: prepared and filled with Ceraseal (CS) + Single Cone Technique (SCT), Group 4: prepared and CS + Cold Lateral Compaction Technique (CLCT), Group 5: prepared and filled with AH Plus Jet (AHPJ) + SCT, Group 6: prepared and filled with AHPJ + CLCT. Vertical force was applied to the universal test machine until fracture occurred, and the maximum force required to fracture was recorded. Results: The Positive control group had significantly less FR than other groups, while the negative control group had significantly more FR than other groups (P.05). Conclusions: There was no significant difference between root canal-filling sealer and techniques.