Bond Strength Of Indirect Restorations Research Articles

Effect of Immediate Dentin Sealing on the Bonding Performance of Indirect Restorations: A Systematic Review.

The popular immediate dentin sealing (IDS) technique is used to improve the bond strength of indirect restorations. This systematic review assessed whether bond strength is affected by the type of aging conditions, bonding agents, flowable resin composites, impression materials, temporary materials, and/or resin cement used within the IDS procedure. A comprehensive database search of PubMed, Embase, Scopus, Ovid Medline, Web of Sciences, Cochrane Library, Dentistry & Oral Sciences Source, and ProQuest was carried out up to 30 January 2024 without publication year or language limitations. Only in vitro full-texts regarding the effect of IDS on bond strength were included, and the quality of their methods was assessed via a Risk of Bias (RoB) test. In total, 1023 pertinent studies were initially found, and 60 articles were selected for review after screening for the title, abstract, and full texts. IDS application improves the bond strength of indirect restorations to dentin and reduces the negative effects of temporary materials on the bond durability of final indirect restorations. Filled dentin bonding agents or combinations with flowable resin composite are preferred to protect the IDS layer from conditioning procedures.

Effect of different application strategies of universal adhesive used for immediate and delayed dentin sealing on the microtensile bond strength of self-adhesive resin cement to dentin with and without aging.

Bond strength of indirect restorations is a very important issue that should be given special attention. Immediate dentin sealing (IDS) technique has been suggested in recent years. The aim of the present study was to investigate the effect of different strategies of universal adhesive application for immediate and delayed dentin sealing (DDS) on the microtensile bond strength (μTBS) of self-adhesive resin cement with and without aging. In this experimental study, 24 healthy human third molars were selected. After exposing the occlusal dentin, the teeth were randomly divided into two groups of 12 based on the All-Bond Universal adhesive application strategy (etch-and-rinse or self-etch). Each group was further subdivided into two (n=6) based on IDS or DDS technique. Then composite blocks were cemented on the occlusal surface with self-adhesive resin cement. After cutting the samples into 1 mm2 cross-sections, half of the samples of each subgroup were subjected to µTBS test after one week, and the other half were tested under μTBS after 10,000 thermal cycles. Data were analyzed using three-way ANOVA (P<0.05). μTBS was significantly affected by all three factors of bond strategy, sealing technique and aging. There was also a significant interaction between the three factors. Immediate dentin sealing improved μTBS. The etch-and-rinse strategy resulted in higher μTBS, while aging led to a decrease in μTBS. Key words:Adhesives, dental bonding, dentin, universal, sealing.

Effect of immediate dentin sealing, bonding technique, and restorative material on the bond strength of indirect restorations

Objective: The objective of this study was to evaluate the effect of immediate dentin sealing, bonding technique, and restorative material on the dentin bond strength of an indirect composite (Solidex) and a resin nanoceramic CAD/CAM block (LAVA Ultimate). Material and Methods: A total of 120 periodontally extracted human molar teeth were abraded horizontally and divided into two groups according to dentin sealing procedures (delayed dentin sealing [DDS] and immediate dentin sealing [IDS]). Next, all teeth were attached to a simulated pulpal pressure mechanism. The specimens were removed from the mechanism after a week. Teeth were subdivided into three groups based on the bonding technique and the type of cement used (Acid-etching + Single Bond Universal + RelyX Ultimate, Single Bond Universal + RelyX Ultimate, RelyX Unicem). Each subgroup was further divided into 2 subgroups according to the type of restorative material used (Solidex [n=10], Lava Ultimate CAD/CAM restorative material [n=10]).. Sixty cylindrical samples prepared using both the restorative materials were bonded to the tooth surface according to their group’s bonding procedures. All specimens were embedded in chemically cured acrylic resin for shear bond strength test. The shear bond strength (SBS) of the specimens was determined by a universal testing machine with a headspeed of 0.5 mm/min. Results: Three-way ANOVA, independent-sample t test and post hoc Tukey comparison tests (?=0.05) were performed on all data. There were significant differences between the groups. It was found that IDS process significantly increased bond strength in all groups. When dentin bond strengths of tested luting cements were compared, the highest bond strength values were recorded in groups in which the specimens were luted with RelyX Ultimate cement using etch-and-rinse technique. The lowest bond strength values were obtained from groups that used RelyX Unicem as the luting cement. Conclusions: IDS improves bond strength of indirect restorations. Moreover, bonding techniques may have critical effects on the dentin bond strength of indirect restorative materials. The cements’ specific affinity levels to both restorative materials and dentin could be considered as the reason of the situation.KEYWORDSIDS; Luting cement; Shear bond strength; Resin nanoceramic; CAD/CAM.

Long-term effect of chlorhexidine on the dentin microtensile bond strength of conventional and self-adhesive resin cements: A two-year in vitro study

Since degradation of the adhesive interface plays an important role on dental restoration failure overtime, bonding protocols containing metalloproteinase synthetic inhibitors could be a valuable approach to preserve the bond strength of indirect restorations. A flat dentin surface was created on 40 recently extracted non-carious human third molars (n=10). Resin-composite blocks were randomly cemented using two resin cements: a self-adhesive and a conventional. A buffer-free 2% chlorhexidine digluconate solution was used as dentin pretreatment on experimental groups. Microtensile bond strength test was performed immediately and after specimen aging for two-years in artificial saliva. Fracture patterns were determined by SEM. Even after significant reduction in bonding effectiveness with aging, dentin bond strength values of the conventional resin cement remained higher compared to those of the self-adhesive resin cement especially when chlorhexidine pretreatment was performed. No statistical differences were observed between immediate and aged specimens luted with the self-adhesive resin cement. Chlorhexidine was effective to preserve dentin bond strength of indirect restorations when the conventional resin cement was used.

The Effect of Prophylaxis Method on Microtensile Bond Strength of Indirect Restorations to Dentin

The aim of this study was to evaluate the effect of different materials used for dentin prophylaxis on the microtensile bond strengths (μTBS) of adhesively cemented indirect composite restorations. Sixty bovine incisors had the buccal surface ground with wet #600-grit silicon carbide abrasive paper to obtain a flat exposed superficial dentin and were submitted to different prophylaxis protocols, as follows: 3% hydrogen peroxide (HydP); 0.12% chlorhexidine (Chlo); sodium bicarbonate jet (SodB); 50-μm aluminum oxide air abrasion (AirA); pumice paste (PumP), and control group-water spray (Cont). After prophylaxis protocols a resin composite block (3.0 mm × 5.0 mm × 5.0 mm) was adhesively cemented using dual resin cement (Rely X ARC). After 24 hours of water storage, specimens were serially sectioned perpendicular to the bonded interface into 1-mm-thick slices. Each specimen was trimmed with a diamond bur to an hourglass shape with a cross-sectional area of approximately 1.0 mm(2) at the bonded area. Specimens were tested (μTBS) at 0.5 mm/min using a universal testing machine. Scanning electron microscopy was used to examine the effects of prophylaxis techniques on dentin. Bond strength data (MPa) were analyzed by one-way analysis of variance and failure mode by Fisher test (α=0.05). μTBS data, means (SD), were (different superscripted letters indicate statistically significant differences): AirA, 25.2 (7.2)(a); PumP, 24.1 (7.8)(a); Chlo, 21.5 (5.6)(a); Cont, 20.6 (8.1)(a); HydP(,) 15.5 (7.6)(b); and SodB(,) 11.5 (4.4)(c). The use of aluminum oxide air abrasion, pumice paste, and chlorhexidine before acid etching did not significantly affect μTBS to dentin; however, the use of hydrogen peroxide and sodium bicarbonate jet significantly reduced μTBS.

Effect of pre-heated dual-cured resin cements on the bond strength of indirect restorations to dentin

This study evaluated the effects of resin luting agents (LA) polymerized using increased temperature on the in vitro microtensile bond strength (mTBS) of indirect restorations to dentin. The occlusal dentin surfaces of 40 human third molars were exposed and flattened. The teeth were assigned to 8 groups (n = 5) according to the LA temperature (25°C o r 50°C), curing mode (dual- or self-curing mode), and product (Excite DSC/Variolink II [VII] and XP Bond/Calibra [Cal]). The bonding agents were applied to the dentin surfaces according to manufacturers' instructions. For preheated groups, the LAs were heated to 50°C, subsequently mixed on a heated stirrer surface, and applied to the previously heated pre-polymerized resin discs (2 mm thickness, TPH-Spectrum). The discs were bonded to the dentin surfaces, and the LAs were either exposed to a curing light according to manufacturers' instructions or allowed to self-cure. Specimens were stored in relative humidity at 37°C for 7 days. Specimens were mesio-distally and bucco-lingually sectioned to obtain multiple bonded beams with a 1-mm² cross-sectional area for mTBS testing. Data (MPa) were analyzed by 2-way ANOVA and Tukey's post hoc test (a = 5%) for each product. Specimen failure patterns were analyzed using a scanning electron microscope. VII groups showed higher mTBS at 50°C than at 25°C regardless of curing mode (p = 0.05). Cal groups showed similar mTBS at 25°C and 50°C in all activation modes. The use of some dual-polymerizing LAs at 50°C may improve the mTBS of indirect restorations to dentin.

Evaluation of bond strength of self-adhesive cements to dentin with or without application of adhesive systems.

To evaluate the bond strength of indirect restorations to dentin using self-adhesive cements with and without the application of adhesive systems. Seventy-two bovine incisors were used, in which the buccal surfaces were ground down to expose an area of dentin measuring a minimum of 4 x 4 mm. The indirect resin composite Resilab was used to make 72 blocks, which were cemented onto the dentin surface of the teeth and divided into 4 groups (n = 18): group 1: self-adhesive resin cement BiFix SE, applied according to manufacturer's recommendations; group 2: self-adhesive resin cement RelyX Unicem, used according to manufacturer's recommendations; group 3: etch-and-rinse Solobond M adhesive system + BiFix SE; group 4: etch-and-rinse Single Bond 2 adhesive system + RelyX Unicem. The specimens were sectioned into sticks and subjected to microtensile testing in a universal testing machine (EMIC DL- 200 MF). Data were subjected to one-way ANOVA and Tukey's test (α = 5%). The mean values (± standard deviation) obtained for the groups were: group 1: 15.28 (± 8.17)a, group 2: 14.60 (± 5.21)a, group 3: 39.20 (± 9.98)c, group 4: 27.59 (± 6.57)b. Different letters indicate significant differences (ANOVA; p = 0.0000). The application of adhesive systems before self-adhesive cements significantly increased the bond strength to dentin. In group 2, RelyX Unicem associated with the adhesive system Single Bond 2 showed significantly lower mean tensile bond strengths than group 3 (BiFix SE associated with the etch-and-rinse Solobond M adhesive system).

Effect of Resin Coat Technique on Bond Strength of Indirect Restorations after Thermal and Load Cycling

To evaluate the ability of the resin-coat technique used in cavity preparation to protect dentin before impression taking and final cementation and its effect on the tensile bond strength of indirect restorations after thermal and load cycling. Occlusal enamel was removed from 25 third molars to expose flat dentin. Teeth were divided into 5 groups (n=5): G1, receiving no dentin sealing (control group); G2, dentin was hybridized with all-in-one self-etch adhesive (Clearfil S3); G3, receiving combination of a one-step self-etch adhesive and low viscosity resin (Clearfil Protect Liner); G4, dentin was hybridized with "two-step" self-etch adhesive (Clearfil SE Bond); and G5, combination of a "two-step" adhesive system and low viscosity resin was applied. After dentin sealing, indirect restorations were performed with Sinfony system and cementation with dual-cure resin cement (Panavia F). Restored teeth were submitted to thermal (1,500 cycles) and mechanical cycling (200,000 cycles). After this they were sectioned into sticks (1×1 mm, approximately) and then subjected to microtensile bond strength testing. all data were submitted to ANOVA and Tukey test (p<0.05). Mean values (MPa) obtained were G1, 9.5; G2, 9.2; G3, 14.8; G4, 12.2; and G5, 17.4. Statistical analysis showed differences between groups, with G5 performance being higher than that of the other groups. when no resin coating-technique was used to protect dentin, lower bond strength values were obtained than those in the other groups. The combination of a "two-step" self-etch adhesive system and low viscosity resin promoted the best bond strength values.

Effect of a bonding resin layer associated with a self-etching adhesive system on the bond strength of indirect restorations

The aim of this study was to evaluate the influence of a low-viscosity bonding resin applied over a self-etching adhesive system on the microtensile bond strength (μTBS) of indirect restorations. Comparisons were made using One Up Bond F (OB) self-etching adhesive system, Single Bond (SB) one-bottle adhesive system and Scotchbond Multi Purpose Plus (SMP) bonding component. Thirty bovine incisors were extracted and decoronated at the cementoenamel junction. The labial surfaces were ground so that superficial dentin and deep dentin were exposed. The specimens were randomized to three groups (n=10): G1- OB; G2- OB + SMP; G3- SB. In G2, a layer of the SMP bonding was applied over the OB adhesive system. Indirect composite restorations were bonded using dual-cure cement under 500 g load for 5 min. The specimens were serially sectioned with a bonding area of ± 1.0 mm2 in 3 regions: enamel (E), superficial dentin (SD) and deep dentin (DD). The sticks were fixed with cyanoacrylate adhesive and submitted to μTBS test at a crosshead speed of 0.5 mm/min in a mechanical testing machine (EMIC DL 2000). The fractured specimens were examined under scanning electron microscopy to determine the failure mode. Data were analyzed by one-way ANOVA followed by Tukey's test (p<0.05). μTBS means (in MPa) were: G1/E: 15.5 ± 3.5b; G1/SD: 22.7 ± 7.6a; G1/DD: 19.4 ± 9.4a; G2/E: 15.9 ± 5.8b; G2/SD: 19.9 ± 6.9a; G2/DD: 15.3 ± 4.9a; G3/E: 23.2 ± 7.3a; G3/SD: 20.4 ± 8.2a; G3/DD: 19.1 ± 8.7a. The results showed that the use of a low viscosity bonding resin did not affect the μTBS means when associated with a self-etching adhesive system. The self-etching adhesive system was significantly more efficient in dentin than in enamel, while the one-bottle system was significantly more efficient in enamel when compared to the self-etching adhesive system.

Immediate dentin sealing improves bond strength of indirect restorations

Immediate dentin sealing improves bond strength of indirect restorations

Immediate dentin sealing improves bond strength of indirect restorations

Delayed dentin sealing is traditionally performed with indirect restorations. With this technique, dentin is sealed after the provisional phase at the cementation appointment. It was demonstrated that this chronology does not provide optimal conditions for bonding procedures. Immediate dentin sealing (IDS) is a new approach in which dentin is sealed immediately following tooth preparation, before making the impression. The purpose of this study was to determine whether there were differences in microtensile bond strength to human dentin using IDS technique compared to delayed dentin sealing (DDS). Fifteen freshly extracted human molars were obtained and divided into 3 groups of 5 teeth. A 3-step etch-and-rinse dentin bonding agent (DBA) (OptiBond FL) was used for all groups. The control (C) specimens were prepared using a direct immediate bonding technique. The DDS specimens were prepared using an indirect approach with DDS. Preparation of the IDS specimens also used an indirect approach with IDS immediately following preparation. All teeth were prepared for a nontrimming microtensile bond strength test. Specimens were stored in water for 24 hours. Eleven beams (0.9 x 0.9 x 11 mm) from each tooth were selected for testing. Bond strength data (MPa) were analyzed with a Kruskal-Wallis test, and post hoc comparison was done using the Mann-Whitney U test (alpha=.05). Specimens were also evaluated for mode of fracture using scanning electron microscope (SEM) analysis. The mean microtensile bond strengths of C and IDS groups were not statistically different from one another at 55.06 and 58.25 MPa, respectively. The bond strength for DDS specimens, at 11.58 MPa, was statistically different (P=.0081) from the other 2 groups. Microscopic evaluation of failure modes indicated that most failures in the DDS group were interfacial, whereas failures in the C and IDS groups were both cohesive and interfacial. SEM analysis indicated that for C and IDS specimens, failure was mixed within the adhesive and cohesively failed dentin. For DDS specimens, failure was generally at the top of the hybrid layer in the adhesive. SEM analysis of intact slabs demonstrated a well-organized hybrid layer 3 to 5 microm thick for the C and IDS groups. For DDS specimens the hybrid layer presented a marked disruption with the overlying resin. When preparing teeth for indirect bonded restorations, IDS with a 3-step etch-and-rinse filled DBA, prior to impression making, results in improved microtensile bond strength compared to DDS. This technique also eliminates any concerns regarding the film thickness of the dentin sealant.