Resin Cement Systems Research Articles

Investigation of the Effect of Indirect Ultrasonic Force and Different Cements on the Bond Strength of Glass Fiber Posts in Teeth with Different Post Space Preparation Methods

(1) Background: The main aim of this study was to investigate the effects of different cements (Panavia V5, RelyX U200) and placement techniques (indirect ultrasonic vibration and manual method) on the bond strength of glass fiber posts in teeth with different post space preparation methods and to evaluate the failure types. (2) Methods: A total of 120 human upper central teeth were collected for the study. One week after root canal treatment, 10 mm long post space preparation was performed using post drills. Post spaces were irrigated in three different ways, namely NaOCl, NaOCl + EDTA solutions, and passive ultrasonic irrigation of NaOCl and EDTA solutions. Glass fiber posts were divided into two groups for resin cement systems, namely RelyX U200 (3M ESPE) or Panavia V5 (Kuraray Medical). Two different methods, namely the indirect ultrasonic vibration and the manual method, were applied for post placement. Then, 1.2 mm sections were taken from the middle and coronal regions of the inserted fiber posts for a push-out test. (3) Results: the Irrigation × Cement (p = 0.002), Cement × Section (p = 0.043) and Placement × Section (p = 0.049) pairwise interactions were statistically significant. (4) Conclusions: in our study, the effects of different post cavity preparations, different cement types, and different placement techniques on the bond strength of the fiber post were observed.

Effect of Er:YAG laser on debonding zirconia and lithium disilicate crowns bonded with 2- and 1-bottle adhesive resin cements.

Erbium-doped yttrium-aluminum-garnet (Er:YAG) laser debonding of zirconia and lithium disilicate restorations is increasingly used for a range of clinical applications. Using rotary instruments to remove such restorations for any purpose has proven to be challenging. Erbium laser has been reported to be a conservative method for removing ceramic restorations. There is little data in the literature about the effect of adhesive resin cement type on the debonding time of the ceramic restoration using the Er:YAG laser. To evaluate and compare the time required for the Er:YAG laser to debond zirconia and lithium disilicate crowns bonded with a 2- and 1-bottle adhesive resin cement systems. Forty extracted premolar teeth were prepared and scanned for milled 40 CAD/CAM crowns. Teeth were randomly assigned into groups (n = 10 per group): 3 mol% yttria-partially stabilized zirconia crowns 3Y-PSZ (G1a) bonded with Panavia™ V5 (2-bottle adhesive resin cement), Zirconia 3Y-PSZ crowns (G1b) bonded with RelyX™ Ultimate (1-bottle adhesive resin cement), and for the lithium disilicate crowns bonded with the two types of cements (G2a, G2b). Each specimen was irradiated with an Er:YAG laser at 335 mJ, 15 Hz, 5.0 W, and 50-ms pulse duration (super short pulse mode). The irradiation time required for crowns to be successfully debonded was recorded for each specimen. Data were statistically analyzed using ANOVA and Tukey HSD post-hoc test (p < 0.05), at the 95 percent level of confidence. The intaglio surface of the debonded crown was analyzed using scanning electron microscopy (SEM). The mean ± standard deviation times needed for crown debonding were 5.75 ± 2.00 min for the G1a group, 4.79 ± 1.20 min for group G1b, 1.69 ± 0.49 min for group G2a, and 1.12 ± 0.17 for group G2b. There was no statistically significant difference in debonding time between the 2- and 1- bottle adhesive resin cement within the groups G1a and b (p = 0.2914), or between groups G2a b (p = 0.7116). A statistically significant difference (p < 0.05) was found between groups G1a and G2a and b and between groups G1b and G2a and b were SEM analysis showed no changes in the microstructure of the ceramic surface after Er:YAG laser irradiation. Zirconia and lithium disilicate restorations can be debonded using Er:YAG lasers in a safe and efficient manner. There is no significant difference in the debonding time between the 2- and 1- bottle adhesive resin cement systems used in this study. Retrieving zirconia and lithium disilicate ceramics can be a challenging process when using diamond rotary instruments. ER:YAG lasers may efficiently debond these ceramics from the tooth structure, independent of the bonding process used for bonding them.

The effect of combining primers and cements from different cement systems on the bond strength between zirconia and dentin

ObjectiveThe aim of this study was to evaluate the influence of combining primers and cements from two different resin cement systems on the microtensile bond strength (μTBS) between zirconia and human dentin.Materials and methodsA total of 120 specimens of zirconia cemented to dentin were allocated into eight groups based on cement type (RelyX Ultimate or Panavia V5) and primers (Tooth Primer, Clearfil Ceramic Primer and Scotchbond Universal Adhesive) combinations, applied to dentin or ceramic surfaces. Following artificial aging with 5000 thermocycles, μTBS tests were conducted. Statistical analysis was performed using One-way ANOVA and Tukey’s post hoc tests (p ≤ 0.05), and failure modes were assessed.ResultsThe Panavia V5 cement system demonstrated the highest bond strength (19.4 ± 4.4 MPa), significantly higher than the other groups except when RelyX cement was used with Panavia primers (16.9 ± 3.7 MPa). Cohesive fractures within the cement layer were the predominant failure mode.ConclusionsThe combination of primers from different adhesive cement system brands may significantly affect the bonding effectiveness. Therefore, using products from a single product line of the same adhesive cement system, and following the manufacturer’s recommendations for indications and use, is crucial for a more predictable clinical outcome.

Evaluation of the Effects of Different Types of Resin Cement Systems on the Push-Out Bond Strength of the Fiber Post to Intracanal Dentin in Anterior Primary Teeth.

This study aimed to evaluate the effects of using three different resin cements on push-out bond strength (PBS) of fiber posts to root canal dentin of primary teeth. Fifty primary canines were randomly divided into five experimental groups according to the type of the luting agent used for fiber post cementation after endodontic treatment and post space preparation as the following: Group 1: glass ionomer cement (GIC), Group 2: flowable resin composite, Group 3: etch and rinse (E&R) resin cement, Group 4: self-etch (SE) resin cement, Group 5: self-adhesive (SA) resin cement. The PBS values of the cemented fiber posts to root canals were measured. The data were statistically analyzed using a one-way analysis of variance, followed by Tukey's post hoc test. The highest mean PBS value was observed in Group 4 (SE resin cement), followed by Group 3 (E&R resin cement), and the lowest PBS value belonged to Group 1 (GIC), followed by Group 5 (p-values < 0.05). The mean PBS of Group 3 (E&R resin cement) was significantly higher than those of Groups 1 (GIC), 2 (flowable resin composite), and 5 (SA resin cement) (p-values < 0.05). However, no significant difference was found between the mean PBS of GIC and SA resin cement (p-value >0/05). Using SE resin cement for fiber post cementation in primary anterior teeth showed the best results, followed by E&R resin cement. The lowest PBS was observed for GIC, followed by SA resin cement.

Lipopolysaccharide penetration analysis of two different resin cement systems to dentin and ceramic surface

Background/purposeOne of the challenges in adhesive ceramic restorations is deterioration of tooth-cement-ceramic interfaces. This study was to quantitatively investigate lipopolysaccharide (LPS) penetration through adhesive ceramic restorations. Materials and methodsStandardized holes were formed on ceramic (IPS Empress CAD, Ivoclar Vivadent) and human dentin discs. Prepared discs were randomly assigned to experimental groups (n = 6/group): SC, self-adhesive resin cement (SmartCem 2, Dentsply Sirona) bonded to ceramic discs; ST, self-adhesive resin cement bonded to dentin discs; VC, etch-and-rinse resin cement (Variolink II, Ivoclar Vivadent AG) bonded to ceramic discs; VT, etch-and-rinse resin cement bonded to dentin discs. The specimens underwent thermocycling (10,000 cycles; 5–55 °C) then LPS penetration test until 5-weeks. A mixed effect analysis using R statistical language was performed for data analysis. ResultsDentin and ceramic bonded with etch-and-rinse resin cements (groups VT and VC) showed significantly less penetration than those with self-adhesive resin cement (groups ST and SC) (P < 0.05). ST showed significantly lower penetration than SC (P < 0.05), that showed similar penetration with positive control (P > 0.05). VC showed minimal penetration during observed time of period (P < 0.05). Scanning electron microscope observations showed different interfacial characteristics among the groups. ConclusionWithin the limitation of this study, etch-and-rinse resin cement showed less LPS penetration than self-adhesive resin cement on both ceramic and dentin surfaces.

An In-Vitro Study Comparing The Push Out Bond Strength Of A Fiber Post System Employing Four Different Resin Cements.

Background: Debonding is one of the common reasons for failure in fiber-reinforced composite posts, and it tends to occur at the post space-dentin adhesive contact. The goal of this investigation was to evaluate the push-out bond strength of a fiber-reinforced post system by using four distinct types of resin cement.Materials and Methods: This in-vitro research used a decoronation technique on forty mandibular premolars, and endodontic treatment was performed on the roots. After the post space preparation was complete, the root specimens were divided up into four groups of ten each and categorized accordingly. The following are the names of the four resin cement systems that were used to cement fiber-reinforced composite posts: (a) Multilink Speed, (b) Rely X Unicem, (c) Calibra, and (d) Permaflo DC. Three portions of each root were cut to a thickness of three millimeters, and these parts were prepared. The bond strength values were determined by performing a push-out test using a universal testing machine at a crosshead speed of one millimeter per minute (mm/min). After compiling the results, a post-hoc Scheffe test and multivariate analysis of variance (MANOVA) were carried out on the data.Result: The product with the greatest mean push-out bond strength was Rely X Unicem, followed by Multilink Speed and then Permaflo DC. Calibra was found to have the mean push-out bond strength that was the lowest. Using the MANOVA and post-hoc Scheffe tests, we discovered that the push-out bond strength of resin cement varied significantly across the various root canal areas. These variations were statistically significant.Conclusion: The mean push-out bond strength of Rely X Unicem was the greatest, followed by Multilink Speed and Permaflo DC in that order. When compared to Calibra, the mean push-out bond strength was found to be the weakest.

Impact of Resin Cement and Adhesive Systems on the Bond Strength of Polyetheretherketone Dental Restorations

Impact of Resin Cement and Adhesive Systems on the Bond Strength of Polyetheretherketone Dental Restorations

A randomized, controlled clinical evaluation of two resin cement systems in the adhesion of CAD/CAM-fabricated resin nanoceramic restorations: 18-month preliminary results.

The purpose of this clinical study was to evaluate the performance of two different adhesive resin cement systems in the cementation of inlay/onlay restorations produced from resin nanoceramic blocks using the CAD/CAM system. A total of 70 inlay/onlay restorations made from Cerasmart (GC, Tokyo, Japan) resin nanoceramic blocks using CEREC Omnicam (Sirona Dental, Bensheim, Germany) were placed in 53 patients. The restorations were cemented with RelyX U200 Automix (3M ESPE, Seefeld, Germany) self-adhesive resin cement (RXU) after selective enamel etching or with G-CEM LinkForce (GC, Tokyo, Japan) adhesive resin cement (GCL) in combination with a universal adhesive (G-Premio Bond) in selective etch mode. At baseline and after 6, 12, and 18 months, restorations were examined by two calibrated clinicians according to modified USPHS criteria. The data were analyzed using Chi-square (χ2 ) test and Friedman test (p <0.05). After 18 months, two teeth at RXU group were endodontically treated due to hypersensitivities. At GCL group, three restorations were lost due to debondings (2) and ceramic fracture (1). The survival rates of RXU (94.3%) and GCL group (91.4%) exhibited no statistically significant difference (p =0.661). No significant differences were detected for surface texture, secondary caries, anatomic form, color match, marginal discoloration, marginal integrity, interproximal contacts, and patient satisfaction (p >0.05). The two resin cement systems showed acceptable clinical performance for the cementation of resin nanoceramic CEREC Omnicam inlay/onlay restorations. Resin nanoceramic restorations fabricated using CEREC Omnicam and cemented with either a self-adhesive or a universal adhesive/resin cement system demonstrated clinically acceptable results for posterior teeth in a single visit.

51 - Bonding Durability of Resin Cement to Lithium Disilicate Glass Ceramics

To obtain reliable adhesion of resin cement to glass ceramics, it is generally known that it is important to apply a silane coupling agent to glass ceramics surface to make its surface has chemically bonding ability. Currently, there are several types of commercial resin cement system with different approach to provide silane coupling agent, such as, prosthesis primer, mixed in bonding agent, or compounded in cement paste. The purpose of this study is to evaluate the bond durability of several resin cement systems to lithium disilicate glass ceramics (LDS) to find reliable system with silane coupling ability. 3 resin cement systems, G-CEM ONE (GO, GC Corporation) with G-Multi Primer (GMP, GC Corporation) which is prosthesis primer included silane coupling agent, PANAVIA SA Cement Universal (PSU, Kuraray) which compounded silane coupling agent in cement paste, and RelyX Universal (RXU, 3 M) with Scotchbond Universal Plus Adhesive(SBU+, 3 M) which is bonding agent mixed silane coupling agent in it were examined. Initial LiSi Block (LiSi, GC Corporation) was used as LDS in this study. LiSi were embedded with acrylic resin. Adhesive surface was finished with 600-grit SiC paper (#600) or hydrofluoric acid (HF)[BISCO PORCELAIN ETCHANT 9.5% HF]. Bonding area(3.0mm-diameter) and cement thickness(0.1mm-thickness) were defined by plastic-tape. Stainless-steel rod was bonded against the bonding area by each resin cement system according to manufacturers instruction in self-curing mode. Bonded specimens were stored in 37 C distilled water for 24 hours(24 h). In case of thermocycling, they were placed under thermocycling condition(5-55 C for 5000cycles:TC5000). Shear Bond strength was tested with universal test equipment (SHIMADZU AG-IC, crosshead-speed 1 mm/min, N=5). Data were statistically analyzed by Tukey-Krame. In case of GO with GMP, there were no significant differences of SBS between 24 h and TC5000 regardless of surface finish (#600 and HF). On the other hand, in case of PSU and RXU with SBU+, SBS of TC5000 on surface finish of #600 significantly decreased compared with SBS of 24 h. From the results, GO with GMP showed high bond strength and bonding durability regardless of surface finish. In case of #600, its finished surface was relatively smooth and mechanical retention would not be expected, but GO with GMP showed the equivalent bonding durability on #600 compared with HF. It might indicate silane coupling ability in GMP was properly functioned and separate prosthesis primer system can be effective. It is expected that better long term bonding durability to lithium disilicate glass ceramics may be achieved by G-CEM ONE system.

Resin bond strength to translucent zirconia: A 2-year follow-up

The aim of this study is to evaluate the effect of aging on resin bond strength to translucent zirconia treated with the most clinically used bonding procedures. Monolithic translucent zirconia-based ceramic (3Y-TZP) blocks were surface treated using airborne-particle abrasion with alumina particles (AP) or silica-coated alumina particles (SC) then bonded to resin composite blocks using a resin cement system containing a silane coupling agent and an adhesive with a phosphate (MDP) monomer. Bar-shaped specimens (bonding area: 1 mm 2 ) were fabricated (n = 30) and stored in 37 °C distilled water for the following time before testing: 7 days (SCI and API); 1 year (SC1 and AP1); and 2 years (SC2 and AP2). Specimens were loaded to failure under tension using an Instron testing machine. Microtensile bond strength (σ f ) data was statistically analyzed using Weibull distribution, analysis of variance (ANOVA) and Tukey tests (α = 0.05). Failures were evaluated using fractographic principles. Mean σ f values significantly decreased after 2 years of water storage (SC2 and AP2) (p < 0.05), although there was no difference in the Weibull modulus. All specimens failed cohesively within the adhesion zone at the zirconia-cement adhesive interface.

Sealing Ability of New Translucent Zirconia Crowns Made with Digital Workflow and Cemented with Different Types of Cement.

This article evaluated the sealing capacity of single crowns made of a new zirconia (Katana STML, Kuraray Noritake) when cemented with two different cement types and two different marginal preparation types. Forty intact human anterior teeth, extracted for periodontal reasons, were used. Each sample was prepared with two margin preparations: knife-edge (KE) on one half of the tooth and chamfer (CH) on the other half. Based on the type of cement used, abutments were randomly distributed into one of two groups: Group 1 used resin cement (Panavia V5, Kuraray Noritake), and Group 2 used reinforced glass-ionomer cement (FujiCEM 2, GC). A digital workflow was utilized for crown fabrication. After the cementing procedures, samples were processed, and microleakage and scanning electron microscopic observations were made. Microleakage varied significantly depending on the type of cement combination used. Group 1 samples showed less microleakage (medians: 0.76 for CH and 0.51 for KE in Group 1, and 4.1 and 3.45 for Group 2, respectively) than Group 2 specimens; the difference was statistically significant (P < .000). KE preparation showed less microleakage than CH, although no statistically significant differences were found (P < .0558). Under microscopic observations, some samples showed internal fractures within the zirconia material. KE and CH seal the margin of zirconia crowns similarly. The resin cement system ensured better adhesion than reinforced glass-ionomer cement.

A randomized controlled study on color stability of tetracycline teeth restored with ceramic veneer.

This study aimed to evaluate the color stability of tetracycline teeth restored with ceramic veneers of different thicknesses combined with different resin cement systems after aging. Twenty patients with tetracycline teeth, including two maxillary central incisors, were selected clinically. The patients were randomly divided into four groups and restored with 0.5 and 0.75 mm ceramic veneers by using a veneer adhesive system, either with light-cured or dual-cured reaction. The color difference (ΔE) values after cementation and 1, 6, 12, and 24 months of use were obtained by quantification of L*, a*, and b* values with a colorimeter. The results were analyzed statistically with two-way ANOVA and Student's t test. The ΔE values of ceramic veneers detected after aging were less than 2.25. The 0.5 mm groups exhibited greater color change than the 0.75 mm-thick veneers (P<0.05). No significant difference was found on the color change of dual- or light-cured resin cements. Resin cements and veneer thickness influence the color of ceramic veneers after aging. Cementation of veneers with either dual- or light-cured resin cements does not affect the long-term color stability of tetracycline teeth differently.

Effect of APF Treatment Of CAD/CAM Ceramics on Bond Strength

Hydrofluoric acid treatment is frequently used for the surface treatment of ceramic restoratives containing silica. However, hydrofluoric acid is extremely toxic and requires great care when used in chair-side situations. Acidulated phosphate fluoride (APF) solution is highly safe and widely used for caries prevention in both children and adults by application to the teeth. Use of a safer alternative to hydrofluoric acid is desirable, so this study aimed to investigate the effects of surface treatment with APF solution combined with heat treatment on bonding to CAD/CAM ceramics. Specimens of ceramics were distributed into five groups: Group A30, treated by 2% APF for 30 min; Group AH1, treated by APF with heat treatment (at 100⁰C for 1 min); Group AH5, treated by APF with heat treatment (at 100⁰C for 5min); Group HF, treated with 8% hydrofluoric acid, and Group CO, without etching treatment as a control. After treatment, specimens were bonded with dual-cured resin cement system. Tensile bond strength was measured after 24h. Mean bond strengths were as follows: Group CO, 11.03 MPa; Group A30, 12.96 MPa; Group AH1, 14.19 MPa; Group AH5, 17.15 MPa; and Group HF, 17.50 MPa. APF treatment combined with additional heat treatment offered effective bonding to CAD/CAM ceramics

In vitro Study of the Effect of Internal Relief Space on the Color of Ceramic Laminate Veneer

BACKGROUND: Ceramic laminate veneer restoring is considered a challenging modality in solving various esthetic dental problems. AIM: The purpose of this study was to investigate the effect of digital internal relief space on the color of ceramic laminate veneer. MATERIALS AND METHODS: An acrylic central incisor model was prepared for ceramic laminate veneer with standard measures. The prepared acrylic resin dentotype model was scanned with intraoral computer-aided design/computer-aided manufacturing (CAD/CAM) optical scanner (CEREC Omnicam|Dentsply Sirona). The laminate veneer design was planned on the optically scanned preparation on CAD/CAM system software (CEREC software|Dentsply Sirona). Thirty ceramic laminate veneer specimens were machined from zirconia-reinforced lithium silicate (Celtra Duo blocks, Dentsply/Sirona) according to standard design by CAD/CAM system with the change of the digital internal relief space settings. The specimens were divided into three groups according to their digital internal relief settings (IRS) (20, 60, and 100 μm) (n = 10). Thirty epoxy dies were duplicated from the prepared acrylic model. The ceramic laminate veneer specimens were cemented to epoxy dies with total etch resin cement system according to the manufacture instructions. The color change (ΔE) of the cemented ceramic laminate veneer specimens was measured by spectrophotometer (Vita Easy shade, Ivoclar Vivadent AG, Schaan, Liechtenstein) using the CIELAB scale and L*, a*, b*. Each specimen was measured two times (before and after cementation). The value of color difference (ΔE) was calculated according to the formula: ΔE = [(L*2 - L*1)2 + (a*2 - a*1)2 + (b*2- b*1) 2]½. RESULTS: The highest mean value of ΔE was recorded in G100 group (1.91 ± 0.33), followed by G60 group (1.83 ± 0.09), with the least value recorded in G20 group (1.49 ± 0.49). Analysis of variance test revealed a statistically significant difference between groups (p = 0.024). CONCLUSION: The change of the digital IRS affects the color of ceramic laminate veneers.

Do resin core build-ups obtain the benefits of higher bonding ability from direct or indirect technique?

Purpose This study evaluated the effects of different materials (composite resin system including a photo-cure adhesive (DC) vs. resin cement system including a self-etching primer (PV)) and techniques (direct vs. indirect) for resin core build-up on the bonding performance to root canal dentin.Methods The human teeth were decoronated and root canal preparation was performed. All specimens were randomly divided into four groups according to the combinations of the methods (Direct or Indirect) and the materials (DC: Clearfil DC Core, Kuraray Noritake Dental or PV: Panavia V5, Kuraray Noritake Dental). Micro-tensile bond strength (μTBS) and push-out tests were performed. Scanning electron microscope observations of the interface were also performed, and microcomputed tomography and optical coherence tomography were applied to evaluate the sealing ability.Results The Indirect group had significantly higher μTBSs than the Direct group in the DC group (P = 0.0076). The PV group had significantly higher bond strengths than the DC group in both the Direct and Indirect groups (P < 0.001). The Direct/PV group demonstrated significantly higher push-out bond strength than the Direct/DC group (P < 0.001). In the Direct/PV group, the formation of resin tags was observed even on the apical side of the canal. Microleakage was more clearly observed in the DC group than in the PV group.Conclusions PV has a higher bonding ability to root canal dentin than DC. When using DC, the indirect technique exhibited a higher bonding ability than the direct technique.

A clinical evaluation of resin nanoceramic CEREC Omnicam restorations associated with several factors.

The aim of this study was to assess the clinical performance of computer-aided design and computer-aided manufacturing resin nanoceramic posterior restorations fabricated by CEREC Omnicam system. Fifty-seven Lava Ultimate posterior restorations were placed in 44 patients by one operator. Restorations were cemented using a resin cement system (Duo-Link). The clinical performance of the restorations was evaluated with USPHS guidelines in a mean time of 45-month. Data were statistically analyzed using Kaplan-Meier and Log Rank (Mantel-Cox) tests (SPSS 22.0, α=0.05). Thirty-eight restorations in 26 patients were evaluated at recall examinations by two evaluators other than the clinician who had placed the restorations who were blinded to groups. The survival rates of Lava Ultimate were 86.8%. A total of 5 (13.2%) failures were found. After a mean time of 45-month survival rate of vital and non-vital teeth were 90 and 83.3% respectively. The failures were not significantly influenced by gender, tooth arch, restoration size, the treated region and vitality. Chair-side posterior resin nanoceramic restorations were clinically successful restorations with a survival rate of 86.8% after a mean time of 45-month. Chair-side CAD/CAM resin nanoceramic restorations can be a successful choice for vital and non-vital teeth with acceptable survival rates.

The Influence of Surface Treatments on Resin Bond Strength to Zirconia

Background: It’s shown that the clinical success of ceramic restorations much depends on the quality and durability of the bond to ceramic. For zirconia-based ceramics (Y-TZP), the surface treatment has a substantial impact on bond strength. Therefore, the bond strength evaluation of Y-TZP surface treatments is a requirement for predicting the clinical performance of such restorations. Objective: Evaluating the resin bond strength to Y-TZP after different surface treatments. Methods: Monolithic Y-TZP (Zenostar Zr Translucent, Wieland Dental, Rosbach vor der Höhe, Germany) blocks were bonded to resin composite blocks using a resin-based cement system after two Y-TZP surface treatments: APA- airborne particle abrasion with alumina particles; and CJ- silicatization (Cojet sand, 3M ESPE, St. Paul, MN, USA). A silane coupling agent and an adhesive system were applied to the treated Y-TZP surfaces and resin composite blocks were cemented (RelyX Ultimate, 3M ESPE, St. Paul, MN, USA) and light activated from all sides. These structures were cut to obtain bar-shaped specimens (n=30), which were stored in 37ºC distilled water for 7 days before microtensile testing. Specimens were loaded to failure under tension using a universal testing machine. Data was statistically analyzed using Students t test (α=0.05) and Weibull distribution. Failure modes were evaluated using optical (OM) and scanning electron microscopy (SEM). Results: Mean bond strength values (CJ= 25.7±8.2 MPa; APA= 22.0±6.3 MPa) were statistically similar (p&gt;0.05). No difference was found for the characteristic strengths (σ0) and for Weibull moduli (m) since the confidence intervals (95% CI) overlapped. The bond strength values for a 5% failure probability (σ5%) were 12.4 (CJ) and 11.5 (APA). All fractures were due to cohesive failure within the adhesive cement system. Conclusion: Both Y-TZP surface treatments (CJ and APA) produced similar structural reliability and short-term bond strength to a resin cement system.

Effect of differences in the type of restoration and adhesive resin cement system on the bonding of CAD/CAM ceramic restorations.

The effect of differences in the type of restoration and adhesive resin cement system on the bonding of CAD/CAM ceramic restoration after cyclic loading was examined quantitatively and qualitatively. Seventy-two human maxillary first molars were divided into three restoration groups: MOD-inlay, MODP-onlay, and crown. Immediate dentin sealing was applied to the exposed dentin of all prepared specimens. The 24 specimens of each restoration group were further divided into another three groups, and a different adhesive resin cement system was applied to each group for cementation. All restoratives were fabricated from feldspathic-ceramic-blocks and cemented with each adhesive resin cement system according to the manufacturer's instructions. The microtensile bond-strength was measured after cyclic loading and was not significantly affected by differences in the type of restoration or adhesive resin cement system. However, the type of restorations and adhesive resin cement systems did show significant differences in terms of the bonding reliability.

Dentin to dentin adhesion using combinations of resin cements and adhesives from different manufacturers – a novel approach

Aims The aims of this study were to present a novel method to analyse dentin bond strength and to evaluate the bond strength of combining adhesive systems and resin cement from different manufacturers. Methods Human wisdom teeth were ground flat to the dentin on parallel surfaces and axially cut into two parts. Dentin cylinders (Ø 3 mm) were drilled from one half of each tooth. The other half from each tooth was embedded in epoxy resin with the dentin surface exposed. The specimens were ground with silicone carbide paper and the dentin cylinders were cemented onto the dentin surface of the other half of the same tooth. Materials: Resin cement and adhesive systems from three different manufacturers were used in various combinations (n = 8 per group). Cement and adhesive from the same manufacturer served as control. Shear bond strength (SBS) was measured and fracture modes were registered. Results and conclusions: The highest median SBS value was found in a bonding combination between cement and a non-corresponding adhesive (33.1 MPa) and one of the lowest values was found in one of the controls (15.3 MPa). Cohesive fractures were most frequent. The results indicated that combining adhesive and cement from different manufacturers did not compromise the dentin bonding. The novel test method is recommended for evaluating dentin bonding.

Effects of adhesive system, thermal aging and ceramic shade on the final color and bond strength of monolithic lithium disilicate ceramics

Aim: The present study aims to observe the effects of adhesive systems and thermocycling on the final color of monolithic lithium disilicate ceramics, also impacts of ceramic shade on the bond strength of resin cement.Material and Methods: Monolithic lithium disilicate ceramic discs in VITA shades A1 and A3 and also self-adhesive, self-etch and total-etch adhesive resin cement systems that were used were investigated in this study. The same color of resin cement (A2 shade) was used for cementation. Ceramic samples of 0,5 mm in thickness were obtained from the IPS e.max CAD blocs. All specimens were distributed into two main groups and six subgroups (n=10) according to the ceramic shade and adhesive system. All specimens were exposed to thermocycling (10,000 cycles). A contact spectrophotometer measured the color differences according to the CIEL*a*b* system. The color differences between before resin cementation (1), after resin cementation procedure (2) and after thermocycling (3), were evaluated. Shear bond strength test was performed after thermocycling.Results: All L values decreased after the resin cementation. The A3-VL (total etch-A3) group had statistically significantly lowest values of L* (p0.05). A3-RX (self-adhesive-A3) group had the statistically significant highest a* and b* values (p0.05). A3-RX group had the highest bond strength results, and there were no statistically significant differences between the A1-VL group (p>0.05). Conclusions: All of the adhesive systems affected the final color of ceramics. Otherwise, the thermal aging procedure did not lead to the changes in the color of the ceramic-resin specimen. Furthermore, ceramic shade affected the bond strength of resin cement after thermocycling.