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 Table of Contents  
Year : 2022  |  Volume : 14  |  Issue : 5  |  Page : 494-499

Impact of maturation time on the shear bond strength of an alkasite restorative material to pure tricalcium silicate based cement: An in-vitro experimental study

1 Department of Conservative Dentistry & Endodontics, Manipal University College Malaysia, Melaka- 75150, Malaysia
2 Department of Oral and Maxillofacial Surgery, Manipal University College Malaysia, Melaka- 75150, Malaysia
3 Department of Prosthodontics, Manipal University College Malaysia, Melaka- 75150, Malaysia
4 Department of Conservative Dentistry and Endodontics, AJ Institute of Dental Sciences, Kuntikana- 575004, Mangalore, India
5 Department of Data Science, Prasanna School of Public Health, Manipal Academy of Higher Education, Manipal- 576104, India

Date of Submission22-Nov-2021
Date of Decision27-Jul-2022
Date of Acceptance31-Jul-2022
Date of Web Publication31-Oct-2022

Correspondence Address:
Dr. Arun Mayya
Department of Conservative Dentistry and Endodontics, Manipal University College Malaysia, Melaka
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jioh.jioh_326_21

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Aim: To evaluate the shear bond strength of pure tricalcium silicate-based cement (Biodentine) to Cention N between two maturation times of Biodentine, namely 12 minutes and 2 weeks. Materials and Methods: 30 acrylic blocks with a hole (3 mm in diameter and 1.5 mm in height) were prepared. Biodentine was mixed according to the manufacturer’s instructions and placed into the holes. The Samples were randomly divided into two groups. In group 1, Cention N was bonded to the Biodentine after 12 mins; in group 2, Cention N was bonded to Biodentine after 2 weeks. A plastic cylinder of height and diameter 2 mm was used to place Cention N over the Biodentine. A universal testing machine was used to measure the shear bond strength of the specimen. Data was analysed using SPSS V15.0. South Asia, Bangalore. Independent sample t-test was applied to compare the mean of the maximum compressive stress of the two groups. Result: Group 2 demonstrated significantly higher shear bond strength values compared to group 1. Lower shear bond strength testing values were observed when Cention N was bonded to an initially set Biodentine. Conclusion: The maturation period of Biodentine has a significant impact on its shear bond strength to Cention N. It is advisable to place the final overlying restoration after waiting for a duration of two weeks to allow the Biodentine maturation to take place.

Keywords: Bioceramics, Biodentine, Cention N, Maturation Time, Shear Bond Strength

How to cite this article:
Mayya A, George AM, Mayya A, D’souza SP, Mayya SS. Impact of maturation time on the shear bond strength of an alkasite restorative material to pure tricalcium silicate based cement: An in-vitro experimental study. J Int Oral Health 2022;14:494-9

How to cite this URL:
Mayya A, George AM, Mayya A, D’souza SP, Mayya SS. Impact of maturation time on the shear bond strength of an alkasite restorative material to pure tricalcium silicate based cement: An in-vitro experimental study. J Int Oral Health [serial online] 2022 [cited 2023 Mar 24];14:494-9. Available from:

  Introduction Top

The conservation and management of the pulp dentine complex form the foundation of conservative dentistry and endodontics.[1] With time, several novel calcium silicate-based materials have been developed for pulp capping and endodontic procedures. Biodentine, a tricalcium silicate bioactive cement with mechanical qualities matching healthy dentin, is one example of this novel family of materials.[2] Its microhardness and flexural and compressive strength give it the appropriate moniker of a ‘dentin substitute’.[3] Several investigations have found that Biodentine has better mechanical qualities, is easier to apply, and sets rapidly compared to the previously utilised mineral trioxide aggregate (MTA).[4] Biodentine is also relatively non-cytotoxic and demonstrates a broad-spectrum antibacterial effect.[5] When Biodentine is used as a dentin substitute, such as in pulp capping procedures, the brittleness and unattractiveness of Biodentine necessitate the use of a different restorative material, such as composite, for the final filling.[6]

There are differing opinions on when the composite restoration can be carried out over the bioceramic material, and what adhesive technique should be used. According to some authors, the final filling should be done after Biodentine has matured for at least two weeks.[7],[8] Because of its biocompatibility, bioactivity, and biomineralisation qualities, the application of Biodentine as a dentin replacement and endodontic repair material beneath composite restorations has been endorsed. The ability of restorative materials to adhere to Biodentine, on the other hand, remains unknown. Unlike MTA, Biodentine permits composite placement over it after 12 minutes of mixing (when the setting begins), but a complete setting takes two weeks.[9] As a result, the working time is reduced compared to MTA, and therapy completion may be possible in a single visit.[2]

Waiting 12 minutes for the adhesion to form may, on the other hand, give rise to difficulties.[10] The bond formed between Biodentine and the overlying filling material affects the quality and endurance of the final repair. As a result, before the final restoration can be completed, a higher degree of Biodentine® setting is required. Even though the producers claim that the final restoration can be completed following the initial setting time of 12 minutes, i.e. in one visit, a longer waiting period (two visits) has been recommended to achieve an improved setting and toughness of Biodentine.[11] Cention N is a restorative material that is “alkasite.” Alkasite is a novel type of restorative material similar to compomers and ormocers and is a subset of the composite material category. Alkaline fillers with the ability to release acid- neutralising ions are employed in this category.[12] Cention N releases ions of calcium, fluoride and hydroxide and is radiopaque. The material is available for use in the A2 shade. Because of its dual-cure nature, full volume (bulk) replacement restorations can be carried out using Cention N. Blue light with a wavelength of roughly 400–500 nm is used for optional light curing.[13]

Cention N is available as separately packed powder and liquid that are mixed by hand directly before usage. One scoop of powder is used for every drop of liquid, resulting in a 4.6–1 powder/liquid weight ratio. Dimethacrylates and initiators make up the liquid, while glass fillers, initiators, and colours make up the powder.[13] No long or short term clinical studies have been performed to evaluate the effectiveness of Cention N due to its brief duration in the market. The bond strength of Cention N to Biodentine has not been investigated till now. It was hypothesised that a better shear bond strength of Cention N to Biodentine could be achieved by waiting for the complete maturation of Biodentine for a duration of two weeks. Therefore, the study aimed to evaluate the shear bond strength of pure tricalcium silicate-based cement (Biodentine) to Cention N between two maturation times of Biodentine, namely 12 minutes and 2 weeks.

  Materials and Methods Top

Setting and design

An in vitro experimental study was carried out at AJ Institute of Dental Sciences, Mangalore during the academic year 2019–2020.

Sample size calculation

Assuming a standard deviation of 5.5 MPa for the maximum compressive stress, in order to detect a true difference in means of 6 units between the two groups, the study would need a sample size of 14 for each group to have an 80% power and a level of significance of 5% (two-sided). The sample size in the current study was 15 per group.

The flowing formula was used to compute the sample size.

n (Sample size per group) = 2 σ2 (Z1-α/2 + Z1-β)2 / d2

Where σ = 5.5 MPa, the standard deviation, d= 6 units, the mean difference

Z1-α/2 =1.96, for 5% level of significance and Z1-β=0.84 for 80% power

Thirty acrylic blocks were randomly allocated into two groups for sample preparation in this study. The maturation time permitted before bonding (12 mins and 1 week) was the grouping variable and the bond strength of Biodentine and Cention N was the outcome variable.


Thirty acrylic blocks with a hole of size 3 mm in diameter and 1.5 mm in height were made. The diameter and height of the holes made were confirmed using a digital vernier caliper and a divider respectively. The manufacturer’s instructions were followed for preparing Biodentine (Septodont, Saint-Maur-des-Fossés, France). Using a capsule mixing device (3 M™ ESPE Rotomix), five drops of liquid were combined with the powder in each capsule for 30 seconds.

A plastic spatula given by the manufacturer was used to handle the generated material. To establish an even surface, Biodentine was initially deposited on a glass slab and gingerly applied to the holes made on the acrylic blocks. A 400-grit paper was used to polish the prepared surfaces for 1 minute in order to create a standard layer. Following Biodentine application into the holes, the samples were allowed to set for 12 minutes for (initial) setting at room temperature.

Cention N (Ivoclar Vivadent) was mixed according to the manufacturer’s instructions. Cention N was centrally placed over the Biodentine using a plastic cylinder of height 2 mm and an internal diameter of 2 mm. The total surface area of bonding between the two materials was 3.14 mm2.

The two groups were based on the maturation time permitted before bonding (12 mins and 1 week). In Group 1 (n = 15), Cention N was bonded to the Biodentine after 12 mins. In Group 2 (n = 15), the samples were stored in an incubator at 37oC and 100% relative humidity for two weeks before bonding to Cention N. Following that, all 30 specimens were kept in an incubator for 28 days at 37°C and 100% humidity.

The shear bond strength (SBS) test was then carried out using a Universal testing machine (Instron 3366, UK). A knife-edge blade was used to apply a crosshead speed of 1 mm/min to each specimen until Biodentine and Cention N bond failed [Figure 1]. The shear bond strength values were calculated through the quotient between the peak break force (N) and the cross-sectional area of the bonded interface (3.14 mm2), are expressed in megapascals (MPa) (1 MPa = 1 N/mm2). The fracture analysis for all the samples were done under a stereomicroscope at 40 × magnification.
Figure 1: Schematic illustration of the shear bond strength test

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Statistical analysis

Data was analysed using SPSS V15. The mean and standard deviation of the maximum compressive stress were computed to summarise the data. Independent sample t-test was applied to compare the mean of the Maximum Compressive Stress of the two groups.

  Results Top

The results are presented in [Table 1] and [Figure 2]

Mean shear bond strength was significantly higher in group 2 compared to group 1 (P < 0.001) [Table 1]. The stereomicroscope inspection of fractured samples revealed that all fractures were mixed mode failures, with some fragments of Cention N adhered to the Biodentine surface.
Table 1: Comparison of Maximum Compressive Stress (MPa)

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Figure 2: Mean shear bond strength and 95% Confidence Interval for Mean

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  Discussion Top

The longevity of a restorative material in the oral environment is determined by its good adhesion to the dentinal surface so as to withstand multiple dislodging forces acting on it. Since the principal dislodging pressure at the interface of the tooth and restoration possess a shearing effect, from a clinical perspective, the shear bond strength becomes critical for the restorative material.[14] As a result, a higher shear bond strength indicates that the material demonstrates better bonding to the tooth or the underlying substance.

The literature currently lacks sufficient data on the effects of maturation time on a tricalcium silicate-based substance like Biodentine, utilised as a dentin substitute, on its shear bond strength to Cention N. A statistically highly significant effect of the maturation time interval was observed in the present study. Comparatively lower shear bond strength testing values were observed when Cention N was bonded to an initially set Biodentine.

Minimum bond strength of 17.20 Mpa has been suggested as a requirement to endure contraction forces of resin composite materials. This bond strength has been confirmed by clinical experiences to be adequate for the retention of composite resin restorations.[15],[16] In the present investigation, the samples of group 2 demonstrated a mean shear bond strength of 17.3 Mpa, which is comparable to that of Composites. Previous studies evaluating the shear bond strength of Composite resins to Biodentin have demonstrated a mean bond strength ranging from 9.34 to 17.7 Mpa.[17],[18]

The applications of Biodentine in dentistry is rather ubiquitous. The indications for its use includes permanent dentine replacements, restorations of carious lesions, pulpotomies, pulp capping, repair of perforations, management of internal and external resorption, apexification and root end filling in endodontic surgery.[19] The maturation of Biodentine takes place in three stages. 1, Tricalcium silicate combines with the water component and forms a hydrated calcium silicate gel (C-S-H) structure and calcium hydroxide. The dissolution of tricalcium silicate grains leads to the precipitation of a calcium silicate gel structure. 2, The nucleation and expansion of the gel structure on the tricalcium silicate surface gradually fills the spaces between the tricalcium silicate grains. 3, Continuous hydration causes the C-S-H gel structure to crystallise, resulting in the creation of CaCO3 crystals between the unreacted grains. Over the course of two weeks, the CaCO3 crystals gradually fill up the porosities between the unreacted cement grains, eventually reaching a maximum.[20]

According to the manufacturers, the initial setting reaction of Biodentine takes approximately 12 minutes, however impedance spectroscopy tests have demonstrated that at least two weeks are necessary for the material to finally set. The CaCO3 crystals are still being formed during this period.[20] Hence, we chose the durations of 12 minutes and two weeks for the immediate and delayed maturation intervals.

In a clinical setting, the restored teeth are almost immediately subjected to masticatory load. However, in the present study, SBS of Biodentine to Cention N was not tested immediately after bonding. Before the shear bond strength test, the study’s specimens were held in a load-free state for up to 28 days. This was done deliberately since the setting reaction of Biodentine can last between 21 days up to a month.[10] Therefore, to prevent a cohesive failure within Biodentine which has not fully set, which could lead to a bias in assessing the shear bond strength of the test materials, all specimens were stored for 28 days. Nonetheless, in vitro shear bond strength studies must be evaluated and applied to clinical situations with caution.

Biodentine goes through an initial setting reaction that takes about 12 minutes after the components are mixed, resulting in a hydrated calcium silicate gel with delayed physicomechanical properties.[20] At this point, a superficial setting is achieved. As a result, compared to the delayed Biodentine ageing group, reduced SBS values were obtained in the group where Cention N was placed over the initially set Biodentine. The Biodentine maturation continues over time, with crystallisation of the calcium silicate hydrate gel lasting anywhere from 14 days to a month. At this point, the bulk setting is completed, which improves physicomechanical properties.[20],[21] This could explain why bond strengths increased from 12 minutes to 14 days.

The liquid of Cention N is made up of four monomers that are often found in resin composites without any acidic monomers or water. In the present study, an adhesive was not used since there is a possibility that the exposure of Biodentin to a liquid with a low pH can disrupt the material from chemically setting by degrading the microstructure of the setting cement by influencing the hydration of tricalcium silicates.[21],[22],[23] Further research with and without using an adhesive can be conducted using Cention N since alkaline pH of Biodentine may buffer the acidic agent and contribute to acceptable bond strength.

The debonded surfaces between Cention N and Biodentin demonstrated a mixed-mode of failure, independent of when Cention N was applied over the Biodentine. This contradicts a previous study with composite resins where a predominantly adhesive failure was recorded in the groups.[21] The mixed mode of failure may be attributable to a predominant micromechanical bonding between the Cention N and Biodentine as well as the reduced shrinkage stresses that Cention N undergoes during polymerisation, thereby displaying better adhesion with the underlying biodentine.

Our findings are consistent with those of Meraji and Camilleri. They found that placing RC on BD, a water-based material, is complex and that dentists must take care while bonding to BD soon after achieving the initial set.[24] Our findings are also consistent with those of Hashem et al., who evaluated the shear bond strength (SBS) of Biodentine (BD), GIC, and resin-modified GIC to composites using a self-etching (SE) adhesive at various ageing durations of the substrate. They found that the “early ageing” BD groups (0, 5, 20, and 24 hours after an initial setting time of 12 minutes) had lower SBS values than the “delayed ageing” BD groups (2 weeks and 1, 3 and 6 months).[8] However, several authors[9],[10],[25],[26] reported contradictory results, demonstrating significant variations in study outcomes.

The bond strength values of Cention N in the second group were comparable to previous studies with composite, which might be due to differences in composition. A combination of urethane dimethacrylate (UDMA), tricyclodecan-dimethanol dimethacrylate (DCP), an aromatic aliphatic-UDMA, and polyethylene glycol 400 (PEG-400) DMA cross-links during polymerisation to form strong mechanical properties and long-lasting stability.[27],[28]

Ytterbium trifluoride, barium aluminium silicate glass filler, calcium barium aluminium fluorosilicate glass filler, isofiller (Tetric N-Ceram technology), and calcium fluorosilicate (alkaline) glass filler are among the fillers used in Cention N.[29] A low shrinkage stress results from the presence of specially patented isofillers that are partially functionalised by silanes, thereby reducing stress on the underlying maturing biodentine and thus contributing to a good bond strength comparable to that of composites, despite the lack of use of an adhesive in the present study.[28]

The significant variability of investigated restorative materials, application times, storage duration, storage media, and adhesive methods makes it difficult to compare the current study’s SBS results to other research studies.

Properties of Cention N such as the dual-curing mechanism, release of fluoride, calcium and hydroxide ions, reduced shrinkage in addition to the superior strength makes Cention N the material of choice for extensive restorations of posterior teeth. The limitation of this study is the absence of clinical simulations prior to the shear bond strength analysis. In a clinical situation, the bond strength will be impacted by the masticatory load, the oral environment, and the different adhesive protocols that can be used. Further research using different storage periods and application of simulated masticatory loads, storage medias and adhesive systems can be done to evaluate the long-lasting bond strength.

  Conclusion Top

Within the limitations of this investigation, it can be inferred that the Biodentine maturation period has a considerable impact on the shear bond strength to Cention N. During Biodentine’s primary maturation phase, the shear bond strength between Biodentin and Cention was significantly lowered. Two weeks maturation for Biodentine is preferable over 12 minutes of maturation time for bonding to Cention N.



Financial support and sponsorship


Conflict of interest

There are no conflicts of interest.

Author contributions

Arun Mayya and Ann Mary George: Study conception, data collection, data interpretation, manuscript writing, manuscript review. Anoop Mayya and Sonia Preshma D’souza: Literature search, manuscript preparation, manuscript editing. Shreemathi S. Mayya: Data analysis, Interpretation and writing of results. All the authors approved the final version of the manuscript for publication.

Ethical approval and institutional review board statement

Not applicable.

Patient declaration of consent

Not applicable.

Data availability statement

The data is available on request from the corresponding author.

  References Top

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Malkondu Ö, Karapinar Kazandağ M, Kazazoğlu E A review on biodentine, a contemporary dentine replacement and repair material. Biomed Res Int 2014;2014:160951.  Back to cited text no. 2
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  [Figure 1], [Figure 2]

  [Table 1]


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