The shear bond strength of MTA with three different types of adhesive systems: An in vitro study

Comparative evaluations of shear bond strength of mineral trioxide aggregate, Biodentine, and calcium-enriched mixture to bulk-fill flowable composite using three different adhesive systems: An in vitro study

Objective

The objective of the study was to assess the shear bond strength of bulk-fill flowable composite resin smart dentin replacement plus when bonded to mineral trioxide aggregate (MTA)-angelus, biodentine, and calcium-enriched mixture (CEM) at two different aging periods (15 min and 72 h) using three distinct adhesive systems. In addition, the study identified the specific modes of failure (adhesive, cohesive, or mixed) using a stereomicroscope and scanning electron microscope.

Materials and Methods

One hundred and twenty-six cylindrical acrylic blocks used in the study were sorted into three groups based on the bioactive substance used to fill the 3-mm diameter and 3-mm high hole in the center of each block. The groups were MTA, Biodentine, and CEM. The specimens were then divided into subgroups based on the aging interval (15 min and 72 h) of the bioactive material and the adhesive system used (two-step total-etch, two-step self-etch [SE], and one-step SE) while bonding to the restorative bulk-fill flowable composite. The shear bond strength values were measured with a universal testing machine, and the data were analyzed using two-way and one-way analysis of variance, followed by a post hoc test. The specimens were assessed under stereomicroscope and scanning electron microscope to characterize the mode of bond failure (cohesive, adhesive, or mixed).

Results

The study showed that the type of adhesive system and the time of bonding affected the shear bond strength of bulk-fill composite to the pulp capping agents (P < 0.05). For MTA, the highest bond strength was observed with two-step SE group at 15 min (18.16 ± 2.97 MPa) (P < 0.05). CEM exhibited the highest bond strength with two-step SE group at 72 h intervals (8.77 ± 1.76) (P < 0.05). The highest bond strength for biodentine group was observed with total-etch group (8.54 ± 1.35 Mpa) and two-step SE (8.19 ± 1.94 Mpa) bonded at 72 h interval (P < 0.05). The majority of the samples in the MTA group (29/42) and CEM group (20/42) showed a cohesive fracture, whereas Biodentine group (22/42) had an adhesive fracture in most of its samples.

Conclusion

MTA demonstrated the highest bond strength with two-step SE group at 15 min, and CEM exhibited the highest bond strength with two-step SE groups at 72 h interval. For biodentine group, the type of adhesive used did not impact the bond strength values.

Does adding accelerators to Mineral Trioxide Aggregate affect the shear bond strength?

Amaç: Bu çalışmada, farklı hızlandırıcı ilave edilen Mineral Trioksit Agregat’ın (MTA) kompozite farklı sertleşme sürelerinde makaslama bağlanma dayanımının (MBD) değerlendirilmesi amaçlanmıştır. Gereç ve Yöntemler: Merkezi boşluklara sahip 120 adet akrilik blok 4 ana gruba ayrıldı. 1. grup (kontrol); sadece MTA, 2, 3 ve 4. grup ise sırasıyla %10 kalsiyum klorür (CaCl2), %23,1 kalsiyum laktat glokonat (CLG) ve %15 disodyum hidrojen fosfat (Na2HPO4) ile karıştırılmış MTA içermektedir. Her grup 2 saat 45 dakika , 24 saat ve 96 saat sertleşme süresine göre 3 alt gruba ayrıldı. Bekleme süreleri tamamlandıktan sonra adeziv sistem (Clearfil SE Bond, Kuraray) ve kompozit rezin (Clearfil Majesty, Kuraray) işlemleri tamamlanan örneklere evrensel test cihazında MBD testi uygulandı. Elde edilen verilerinin karşılaştırmasında, tek yönlü varyans analizi (ANOVA) ve Tukey HSD testleri kullanıldı. Bulgular: Hızlandırıcısız MTA en yüksek ortalama MBD değeri sergiledi. Hızlandırıcısız MTA, hızlandırıcı olarak CLG ve Na2HPO4 eklenen MTA ile kıyaslandığında aralarındaki fark anlamlı bulundu (p&lt;0.0001). Başlangıç sertleşme süresinde alt gruplar arasında istatistiksel olarak anlamlı farklılık gözlenmedi (p&gt;0,05), diğer sertleşme sürelerinde fark anlamlı bulundu (p&lt;0,05). MTA’ya hızlandırıcı olarak CLG ve Na2HPO4 ilavesinin tüm sürelerde MBD değerlerini azalttığı, CaCl2 ilavesinin ise 96 saatin ardından MBD değerini anlamlı olarak yükselttiği gözlendi. Sonuç: MTA içerisine hızlandırıcı eklemek MBD değerini düşürmektedir. Ancak MTA’ya hızlandırıcı olarak %10 CaCl2 eklemek 96 saatin ardından yapılacak restoratif işlemlerde pozitif bağlantı sonuçları ortaya çıkarabilir.

An In vitro Study to Assess the Effectiveness of the Shear Bond Strength of Mineral Trioxide Aggregate with Different Adhesive Systems

Purpose of the Study

Mineral trioxide aggregate (MTA) is a biocompatible material and has excellent sealing ability. It is proved and claimed that it provides double seal due to its physical sealing ability as well as ability to induce cementogenesis that provides biological seal.

Aim and Objectives

The aim of the study was to assess the shear bond strength of MTA with three different types of adhesive systems: (1) self-adhering flowable composite, (2) etch and rinse (ER) adhesive system, and (3) self-etch (SE) adhesive system.

Materials and Methods

Ninety MTA specimens were prepared using cylindrical acrylic blocks, having a central cavity with 2 mm depth and 4 mm diameter. MTA was mixed and placed in the prepared cavity and was covered with moist cotton pellet and temporary filling material (Cavit). They were further divided into three groups which were further divided into two subgroups. After the bonding agents was applied, the composite resin was placed over the MTA surface. The specimens were then tested for shear bond strength; statically analysis was done.

Result

After 24 h, the mean value of ER group was found to be significantly higher than SE and the self-adhering composite groups. Among the 45 min groups, there was no significant difference observed.

Conclusion

In single visit, after 45 min, self-adhering flowable can be used successfully as a final restorative material in place of conventional flowable composite without using any alternative adhesive system over MTA.

Bio-Inductive Materials in Direct and Indirect Pulp Capping-A Review Article

The article is aimed at analyzing the available research and comparing the properties of bio-inductive materials in direct and indirect pulp capping procedures. The properties and clinical performances of four calcium-silicate cements (ProRoot MTA, MTA Angelus, RetroMTA, Biodentine), a light-cured calcium silicate-based material (TheraCal LC) and an enhanced resin-modified glass-ionomer (ACTIVA BioACTIVE) are widely discussed. A correlation of in vitro and in vivo data revealed that, currently, the most validated material for pulp capping procedures is still MTA. Despite Biodentine's superiority in relatively easier manipulation, competitive pricing and predictable clinical outcome, more long-term clinical studies on Biodentine as a pulp capping agent are needed. According to available research, there is also insufficient evidence to support the use of TheraCal LC or ACTIVA BioACTIVE BASE/LINER in vital pulp therapy.

Comparative evaluation of the bond strength of self-adhering and bulk-fill flowable composites to MTA Plus, Dycal, Biodentine, and TheraCal: an in vitro study

Objectives

This study aimed to compare the shear bond strength (SBS) of a self-adhering flowable composite (Dyad Flow) and a bulk-fill flowable composite (Smart Dentin Replacement [SDR]) to several pulp-capping materials, including MTA Plus, Dycal, Biodentine, and TheraCal.

Materials and Methods

Eighty acrylic blocks with 2-mm-deep central holes that were 4 mm in diameter were prepared and divided into 2 groups (n = 40 each) according to the composite used (Dyad Flow or SDR). They were further divided into 4 sub-groups (n = 10 each) according to the pulp-capping agent used. SBS was tested using a universal testing machine at a crosshead speed of 1 mm/min. Data were analyzed using 2-way analysis of variance. A p value of < 0.05 was considered to indicate statistical significance.

Results

A statistically significant difference (p = 0.040) was found between Dyad Flow and SDR in terms of bond strength to MTA Plus, Dycal, Biodentine, and TheraCal.

Conclusions

Among the 8 sub-groups, the combination of TheraCal and SDR exhibited the highest SBS.

Does Delayed Restoration Improve Shear Bond Strength of Different Restorative Protocols to Calcium Silicate-Based Cements?

The purpose of the present study was to assess the proper time to perform a restoration (immediately or delayed) after placement of two calcium silicate-based cements (CSCs) and to test the performance of two different restorative protocols regarding shear bond strength (SBS). Seventy-five acrylic blocks were randomly divided into five groups (n = 15). Specimens were filled with either ProRoot MTA (Dentsply Tulsa Dental) or Biodentine (Septodont). The restoration was performed at an immediate (12 min) or delayed (seven days) timeframe, using a resin-based flowable composite (SDR) (bonded to the CSC using a universal bonding system) or glass ionomer cement (GIC) as restorative materials. SBS was measured using a universal testing machine. Fractured surfaces were evaluated, and the pattern was registered. Statistical analysis was performed using the Dunn–Sidak post hoc test (P < 0.05). Biodentine/immediate SDR showed the highest mean SBS value (4.44 MPa), with statistically significant differences when compared to mineral trioxide aggregate (MTA)/GIC (1.14 MPa) and MTA/immediate SDR (1.33 MPa). MTA/GIC and MTA/immediate SDR did not present significant differences regarding SBS. No statistical differences were verified concerning mean SBS between both CSCs within the 7 day groups. MTA/delayed SDR (3.86 MPa) presented statistical differences compared to MTA/immediate SDR, whereas no differences were observed regarding Biodentine performance (Biodentine/immediate SDR and Biodentine/delayed SDR (3.09 MPa)). Bonding procedures directly on top of MTA might be preferably performed at a delayed timeframe, whereas Biodentine might allow for immediate restoration.