Repair Resin Research Articles

The influence of Two Surface Treatment Techniques with Different Adhesive Systems on the Shear Bond Strength of Composite Resin Repair Shaban A. Aml

purpose: To evaluate the influence of different adhesive application protocols with two surface treatment methods on the shear bond strength of aged composite repair. Material and methods: 90 cylindrical shaped samples (8mm × 4mm) were prepared from Estelite Sigma Quick composite resin, After the thermocycling thesamples were divided into two main groups according to the surface treatment and then each group were further subdivided to five groups according to bonding procedures. For the repair, the same brand of old composite with same shade was used. Then the shear bond strength test was completed by the Universal Testing Machine. For statistical analysis the IBM SPSS statistics program was used (SPSS IBM, Turkey). Results: There was statistical significant difference between the shear bond strength values in Mpa among all sub-groups. conclusion: The shear bond strength obtained by the mechanical surface grinding with diamond bur is statistically significant higher than that obtained with air abrasion surface treatment. The combination of universal adhesive system or two-step self-etch adhesive system and grinding with diamond bur for repair procedures provide the highest values of SBS.

Immediate and Delayed Repair Of Bulk-Fill Composite Resin

Immediate and Delayed Repair Of Bulk-Fill Composite Resin

Repair strength of 3D-printed denture base resins: Effect of surface treatment and repair material type.

The aim of the study was to investigate the effect of surface treatment and repair materials on the flexural strength of repaired 3D-printed denture base resins after thermal aging. Bar-shape specimens (64×10×3.3mm) were designed as intact (control) specimens while repair specimens were printed in sections with 2.5mm space for repair material. Printing was performed with either ASIGA or NextDent denture base material. In each material, one group received no surface treatment, while other repair groups were subjected to one of three surface treatments: (1) monomer application, (2) aluminium oxide particles-abrasion, or (3) both methods (aluminum oxide particles-abrasion and monomer application). Pairs were fixed in a customized mold then repaired with either autopolymerizing acrylic resin or flowable composite (n = 9). Repaired specimens were incubated for 48h at 37°C in distilled water and then subjected to thermal cycling (5000 cycles). A 3-point bending test was used to evaluate the flexural strength using a universal testing machine, and mode of failure determined followed by fractured surface analysis using scanning electron microscope. Data were analyzed using ANOVA and post hoc Tukey test (α = 0.05). Both resin materials showed a significant decrease in the flexural strength of repaired specimens when compared to control ones (p<0.001). Groups with no surface treatment had significantly lower flexural strength than those with surface treatment (p<0.001). Groups treated with monomer application, and with aluminum oxide particles abrasion plus monomer application had similar flexural strength values (p>0.05), which were higher than those treated with aluminum oxide particles abrasion alone (p<0.001). Specimens repaired with composite resin showed higher flexural strength than those repaired with auto-polymerized resin (p<0.05) however, specimens treated with aluminum oxide particles abrasion alone had similar values for both repair materials (p = 0.95). Adhesive failure was dominant in all repaired groups with auto-polymerized while cohesive and mixed were dominant with composite repair groups. Surface treatment improved the repair strength of 3D-printed denture base resins. Using composite resin for repair shows better strength with dominant cohesive and mixed failure suggesting that surface treatment and composite repair are suitable procedures for 3D-printed denture base repair.

Effect of the Application Procedure on The Bond Strength of Universal Adhesive in Restoration Repair

Objective: This study aimed to evaluate the effect of reduced application time on the bond strength of a universal adhesive used for the repair of hybrid ceramic and composite resin restorations. Methods: In the study, a total of 48 rectangular prisms of sizes 7×6×2 mm hybrid ceramic (Vita Enamic, Zahnfabrik, Germany) and composite resin (Solare X, GC, Japan) specimens were prepared. All samples were aged with 5000 thermal cycles. Then, the upper surfaces of the samples were roughened with a diamond fissure bur (10–36µ, 852 FG Meisinger; Hager &amp;amp; Meisinger GmbH, Germany) with 5 strokes under water cooling. The samples were divided into 2 subgroups according to the different application times of the adhesive system (G-Premio Bond, GC, Japan) (n=12). Then, composite resin (Solare X, GC) was placed using plastic cylinder molds with 3 mm inner diameter and height and cured with light for 20 seconds. All samples were thermal aged and then a shear bond strength test was conducted. The data were analyzed with Two-way ANOVA and post-hoc Tukey HSD tests (p˂0,05). Results: Two-way ANOVA revealed that the repair bond strength of the 10 seconds of waiting was significantly higher than the quick application for both hybrid ceramic and composite resin (p˂0,05). It was determined that there was no significant difference between hybrid ceramic and composite resin in the both quick application group and 10 seconds waiting group (p˃0,05). Conclusion: Quick application procedure showed lower shear bond strength than 10 seconds waiting group for the repair of both composite resin and hybrid ceramic (p&amp;lt;0,05). Keywords: Quick application, Application time, Universal adhesive, restoration repair..

Study of Plugging Compositions Based on Synthetic Resins for Repair and Insulation Work in Wells.

This research is aimed at analyzing existing plugging compositions and developing a new plugging composition based on phenol-formaldehyde resin. This paper presents the results of studies of a hardening composition based on phenol-formaldehyde resin for repair and insulation work in wells. The plugging composition consists of two parts: Component "A" (resin and additives) and Component "B" (hardener). A resol-type water-soluble phenol-formaldehyde resin was selected for testing. The resin was additionally modified with special additives to improve performance properties. A mixture of acids was chosen as a hardener. Concentrations of resin and hardener were selected to ensure optimal loss of fluidity of the composition for different temperatures. The main physicochemical properties of the plugging composition were determined. The elastic-strength characteristics of the developed composition after curing at various temperatures (Poisson's ratio, Young's modulus, and compressive strength) were assessed. It has been experimentally proven that samples based on phenol-formaldehyde resin do not collapse completely under load but undergo longitudinal and transverse deformations. As the amount of hardener in the system increases, the compressive strength decreases. The presence of the elastic-strength properties of cementing compositions based on synthetic resins distinguishes them favorably from hardening compositions based on cement and microcement.

Effect of Graphene Oxide Incorporation on the Strength of Denture Repair Resin

To evaluate the effect of incorporating graphene oxide nanoparticles (GO NPs) and graphene sheets on the flexural strength of an auto-polymerized (AP) acrylic resin-repaired denture. 60 heat-activated (HA) resin specimens were fabricated and randomly divided into 6 groups (n = 10). The specimens in Group I were kept intact. 50 specimens were cut into two parts with a 45-degree bevel. Group II specimens were repaired with AP resin and Group III specimens were repaired with HA resin. In the repair of Group IV, Group V, and Group VI specimens, 1%, 2% GO NPs, and graphene sheets were added to AP resin, respectively. A 3-point bending test with a universal test device measured the flexural strength. Statistical analyses of the results were performed with the Kruskal Wallis H-test. (α = 0.05) The flexural strength of Group I (130.05 ± 20.20 MPa) was the highest among all groups. The flexural strength of Group IV (67.49 ± 12.70 MPa) was significantly higher than Group V (50.87 ± 15.02 MPa) and Group VI (44.77 ± 10.70 MPa). The lowest strength value was obtained in Group VI. Adding 1% GO NPs to AP acrylic resins increases flexural strength. However, the increase in nanoparticle concentration and the addition of graphene sheets negatively affect strength.

Ceramic veneers failure: a repair and reintervention clinical report

Introduction and Objective: Although the use of ceramic veneers is widespread, their failures are seldom reported. When fractures do occur, they are often related to treatment planning. This case report describes a 6.5-year follow-up of a restorative treatment involving ceramic laminate veneers on a patient with a nail-biting habit. Case report: After two restorations failed, repair with composite resin was chosen as an intermediary treatment, and the clinical steps until the ultimate replacement of the ceramics are described. Results and Conclusion: The repair resulted in postponing the restorations replacement for almost five years. It highlights that replacement does not need to be the first treatment option in cases of failures of feldspar ceramic laminate veneers. These failures may be managed conservatively with a composite resin repair, with the advantage of postponing the need for replacement.

The efficacy of Er,Cr:YSGG laser and contemporary universal adhesive systems on composite resin repair bond strength: an in vitro study.

The aim of this study is to investigate the repair bond strength of composite resin following three different surface treatments (bur-grinding, silanization, and Er,Cr:YSGG laser irradiation) using various universal adhesives. A total of 160 resin composite specimens, produced in cylindrical form (6 × 2mm) with a nanohybrid composite resin within metal molds, were subjected to 5000 cycles of aging in a thermocycler. The aged samples were categorized into four groups based on surface treatments: control, bur, silane, and Er,Cr:YSGG laser. Following surface treatments, the specimens underwent repair using the same resin composite and four different adhesive systems: Tokuyama Universal Bond (TUB), Prime Bond Universal (PBU), Gluma Bond Universal (GBU), and Clearfil SE Bond (CSB). Subsequently, the specimens were subjected to shear forces, and statistical analysis was performed using two-way ANOVA and Tukey tests (p < 0.05). The failure modes were examined using a stereomicroscope, and the surface topography of the roughened resin composite was assessed through scanning electron microscopy (SEM). Results indicated that silane + GBU exhibited the highest shear bond strength (SBS) (15.61MPa) while control + TUB showed the lowest SBS (7.63MPa). Silane demonstrated significantly higher SBS values (p ≤ 0.05), with no significant difference observed between bur and laser methods (p = 0.998). It is recommended to include an additional silanization step before applying universal adhesive, as it effectively enhances the bond strength of the repaired composite.

Influence of Nanodiamond Incorporation on The Impact Strength of Repaired Denture Base acrylic resin: An in Vitro Study

Aim. This research aims to evaluate the effects of integrating Nanodiamond on the impact strength of repaired denture base resin. Methodology. Sixty acrylic resin specimens, sized 50×6×4 mm³ with a v-notch, were created from heat-polymerized acrylic resin. Ten specimens were kept intact while the other 50 specimens were sectioned to half and prepared with 45º beveling and a 2.5mm-repair gap. Nanodiamond particles were added to autopolymerized repair resin and repaired specimens were placed in five categories (n=10) according to Nanodiamond concentrations, unmodified as a control, 0.25%, 0.5%, 0.75%, and 1%ND by weight. Each specimen half was repositioned in a metal jig, and the repair resin was applied to the repair area. Subsequently, all specimens underwent finishing, polishing, and immersion in distilled water before Charpy's impact testing. Data analysis employed Tukey's post hoc test (with significance α=0.05) and one-way ANOVA. Results. Results showed that in comparison with the control group, the impact strength of repaired denture base resin significantly increased with 0.25% and 0.5% Nanodiamond addition to repair resin (significance at P ˂0.001). While it insignificantly decreased with 0.75% and 1% Nanodiamond (P=0.108 and P=0.615) and 1% presented the lowest value of impact strength (3.48 ± 0.43 KJ/m2). Conclusion. Adding a small amount of Nanodiamond to autopolymerized repair resin demonstrated an increase in the impact strength of repaired acrylic denture base resin. The highest impact strength was recorded with 0.25%ND (6.24±0.55 KJ/m2), followed by 0.5%ND (5.93±0.21 KJ/m2), whereas 1%ND exhibited the lowest impact strength value (3.48±0.43 KJ/m2).

Effect of Liquid Plastic Steel and Epoxy Resin on Pipes

Using different materials to repair mechanical parts in cold state (non-fire repair), the mechanical properties of the repaired materials have different effects. In order to explore the advantages and disadvantages of liquid plastic steel repair agent and epoxy resin repair agent, the repair effects of two cold repair materials were compared. The mechanical properties of L245 pipeline steel before and after repair, such as tensile properties, shear properties and bonding properties, were tested with small size samples. The test results show that the average tensile strength of the reinforced tensile sample of plastic steel is 2MPa higher than that of the ordinary epoxy tree, and the tensile strength is increased by 0.4%; the average yield strength of the reinforced tensile sample of plastic steel is 5Mpa higher than that of the ordinary epoxy tree, and the yield strength is increased by 1.5%. The shear strength of the reinforced tensile specimen of plastic steel is 1.67MPa higher than that of the ordinary epoxy tree reinforced tensile specimen, and the shear strength is increased by 22%.

Effect of reparation on the mechanical behavior of glass fibers/Elium acrylic laminate composites: Experimental and numerical approaches

AbstractElium® Acrylic/Glass Fiber thermoplastic laminate composites are liable to develop irreversible local defects under quasi‐static loading. To reinforce the damaged material, repair is a cost‐effective mechanical alternative. The present study investigates the tensile behavior of an Elium® glass‐fiber‐based acrylic laminate composite panel, repaired by vacuum bonding with Elium® repair resin and double overlap of external patches (DP). The results obtained for all repaired laminate composites E190/GF_D(10, 20, 30)R with diameters 10, 20, and 30 mm showed an improvement in the mechanical properties of the repaired panels, compared with the drilled and pristine samples. Average load recovery rates were significant for E190/GF_D10R (7.9%, 3.55%, 13%) E190/GF_D20R (23%, 18%, 3.32%), E190/GF_D30R (7.2%, 9.36%, 32.37%) at strain rates of 0.001, 0.01, and 0.05 s−1 respectively. Finite element (FE) models for the virgin, drilled, and repaired composite, performed by coupling the Hashin criteria with the cohesive zone model (CZM), provided a relevant prediction of intra‐ and interlaminar failures of these woven laminated composites.Highlights The effect of vacuum bonding repair with Elium E351 EOT resin was studied. Symmetrical repair of acrylic laminate drilled by fiberglass patches. Tensile strength of the repaired laminates was investigated. Intra‐ and interlaminar damage was predicted by finite elements modeling.

Repair of monolithic zirconia restorations with different direct resin composites: effect on the fatigue bonding and mechanical performance

ObjectiveThe study aims to evaluate the shear bond and flexural strength fatigue behavior of yttrium-stabilized zirconia (4YSZ) repaired using different resin composites.Materials and methodsCylindric specimens of 4YSZ were obtained for the bond strength (Ø = 6 mm, 1.5 mm of thickness) and biaxial flexural strength (Ø = 15 mm, 1 mm of thickness) fatigue tests and divided into 3 groups according to the repair resin composite: EVO (nanohybrid), BULK (bulk-fill), and FLOW (flowable). The zirconia surface was air-abraded with alumina particles, a 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) primer was applied, and the resin composite was build-up over the zirconia. Fatigue shear bond strength and flexural fatigue strength tests were performed (n = 15). One-way ANOVA and Tukey post hoc tests were carried out for both outcomes, besides scanning electron microscopy and finite element analysis.ResultsThe repair material affected the fatigue shear bond strength of zirconia ceramic. The BULK group (18.9 MPa) depicted higher bond strength values than FLOW (14.8 MPa) (p = 0.04), while EVO (18.0 MPa) showed similar results to both groups. No effect was observed for the mechanical behavior (p = 0.53). The stress distribution was similar for all groups.ConclusionThe repair of yttrium-stabilized zirconia (4YSZ) ceramics with bulk-fill resin composites was the best option for high fatigue bond strength. However, the fatigue mechanical performance was similar regardless of the applied repair material.Clinical relevanceThe repair of yttrium-stabilized zirconia (4YSZ) monolithic restorations may be performed with nanohybrid and bulk-fill resin composites in order to promote longevity in the treatment.

Effect of different surface treatments on shear bond strength of autopolymerizing repair resin to denture base materials processed with different technologies

To evaluate the effect of chemical, mechanical, and combination surface treatments on the shear bond strength (SBS) of autopolymerizing repair resins to conventional heat-cured, computer aided design (CAD)-computer aided manufacturing (CAM) milled, and three-dimensionally (3D) printed denture base materials. Specimens were fabricated and divided according to the surface treatment as follows: no surface treatment (control group), monomer treatment (monomer group), resin remover treatment (resin remover group), roughening with 180 FEPA grit abrasive paper followed by monomer treatment (180-grit plus monomer group), and air particle abrasion (air abrasion group). Autopolymerizing resin cylinders were attached before accelerated aging of the specimens in water at 100 °C for 16 h. The SBS was tested using a universal testing machine. Surface roughness was evaluated using a 3D optical profilometer. Scanning electron microscopy (SEM) and stereomicroscopy were used for surface analysis. Data was collected and analyzed using analysis of variance (ANOVA) and Kruskall-Wallis tests (α = 0.05). The denture base material and surface treatment significantly affected the SBS. The milled Temp Basic Tissue demonstrated the highest SBS values across all surface treatments, whereas the two 3D-printed denture base materials exhibited the lowest SBS values. The bond strength of CAD-CAM-milled denture base resins to autopolymerizing repair resins is comparable to that of heat-cured resins. Surface roughening using air particle abrasion or 180-grit carbide paper can enhance the bond strength of the autopolymerizing repair resin to 3D-printed denture base materials.

Flexural strength of repaired denture base materials manufactured for the CAD-CAM technique

To evaluate the flexural properties of repaired poly(methylmethacrylate) (PMMA) denture base materials for computer-aided design/computer-aided manufacturing (CAD-CAM) and to compare them with heat-activated polymerized PMMA. A total of 288 specimens (65 × 10 × 2.5 mm) were prepared using both CAD-CAM and conventional blocks and repaired using autopolymerizing and visible-light polymerizing (VLC) materials. Microwave energy, water storage and hydroflask polymerization were applied as additional post-polymerization cycles after the repair process. The flexural strength (FS) of the specimens was evaluated using the three-point bending test. Data were evaluated statistically using 2-way ANOVA followed by Bonferroni's correction to determine the significance of differences between the groups (P ≤ 0.05). The FS of the denture base materials for CAD-CAM was significantly higher than that for the heat-activated group (P ≤ 0.05). The FS was significantly highest when microwave energy was used for the post-polymerization cycle. The FS values for all groups repaired with VLC resin were significantly lower than for the autopolymerization group (P ≤ 0.05). The flexural properties of denture base materials for CAD-CAM repaired using autopolymerizing acrylic resins can recover by 50-70%. Additional post-polymerization cycles for autopolymerizing repair resin can be suggested to improve the clinical service properties of repaired dentures.

Effect of Surface Textures and Fabrication Methods on Shear Bond Strength Between Titanium Framework and Auto-Polymerizing Acrylic Repair Resin.

The aim of the study was to evaluate the effect of airborne particle abrasion (using different sizes of alumina particles) on the shear bond strength (SBS) between cast and milled titanium metal frameworks and auto-polymerizing acrylic repair resin. Forty flat cylindrical titanium disks were divided into two main divisions: cast and milled titanium. The two divisions were further subdivided into four groups based on metal surface treatment. Three particle sizes of aluminum oxide air abrasive powders (50µm, 110µm, and 250µm) were used for metal surface treatment by airborne particle abrasion. One group was the control group with no surface treatment. Auto-polymerizing acrylic repair resin was applied to all titanium disks. The specimens were subjected to SBS testing using a universal testing machine (Instron Corporation, Norwood, Massachusetts, United States). Surface evaluation was performed using a scanning electron microscope. One-way ANOVA was used for statistical analysis. The results showed a significant increase in SBS after airborne particle abrasion of both milled and cast titanium groups (p<0.001). The SBS was directly proportional to the size of the aluminum oxide particles. The milled titanium group showed higher SBS values than the cast group when the surface was not treated with alumina particles (p < 0.001) and when the surface was treated with the smaller particle sizes of 50 µm, whereas the cast group demonstrated higher SBS values than the milled group (p < 0.01) when the particle size was increased to 110 µm and 250 µm. It could be concluded that SBS between titanium metal frameworks and auto-polymerizing repair acrylic resin was directly related to the size of the alumina airborne particle abrasives. The fabrication method of the titanium frameworkalso influenced the SBS as the untreated milled frameworks demonstrated favorable SBS values compared to the untreated cast frameworks.

COMPARISON OF SHEAR BOND STRENGTH OF THREE COMPOSITE RESIN REPAIR MATERIAL WITH CERAMIC AND COBALT CHROMIUM SURFACES AFTER VARIOUS SURFACE TREATMENTS - AN INVITRO STUDY

Aim:The objective of this study was to evaluate the shear bond strength of composite resin repair material with ceramic and cobalt chromium surfaces after various surface treatments and the mode of bond failures by stereo microscope. Materials An Methods: Thirty Ceramic and thirty Cobalt chromium samples (10x10x2mm) were prepared .The samples were divided into three groups for ceramic -CI,CII,CIII and for metal -M1,MII and MIII .Three composite resin repair materials were used (1) Restorative composite (control)- [C Group ] ,(2)SHOFU P &amp; R Ceramic repair kit-[S Group] (3) Ivoclar Ceramic Repair System intro pack after surface modification withintraoral sandblaster – [I Group].The composite material was added 6x4mm using a metal holder .All specimens were subjected to a standard shear load in the universal testing machine until fracture occurred. All debonded samples were examined under stereomicroscope to determine the type of failure .The data was analyzed using one-way ANOVA test of variance and Post hoc comparison was applied at 95 % confidence level. Results: Igroup showed the highest shear bond strength followed by S group in ceramic and metal samples. The C group showed least shear bond strength. The predominant mode of failure among the C group in ceramic and Co Cr metal samples was adhesive failure , S Group showed 50% adhesive and 50% mixed type of failure in ceramic samples (CII) in cobalt chromium samples(MII),it showed 70 % adhesive and 30% mixed failure . I group showed 100% mixed failure in ceramic samples(CIII) group ,and 80% mixed and 20% adhesive failure in cobalt chromium samples(MIII). Conclusion:The surface modified with intra oral sandblaster and repaired with Ivoclar ceramic repair kit showed the most favorable results in ceramic and cobalt chromium samples.

Role of CO2 Laser on SBS between Dental Porcelain and Composite Resin Repair Process

Background. The surface modification of porcelain material can be conducted by mechanical, chemical, or laser means. This study investigated the CO2 laser effect on porcelain to enhance bonding with composite resin. Materials and methods. A total of 33 blocks of feldspathic porcelain were randomly divided into 3 groups of 10. Additionally, three specimens were used in scanning electronic microscopy and energy-dispersive spectroscopy tests. Group I was treated with 9.5% hydrofluoric acid (HF), Group II with a 5 W CO2 laser, and Group III with CO2 followed by etching with 9.5% HF. Then, a Bisco intraoral repair kit was used, followed by the application of repair composite resin (Tetric N Ceram) on the porcelain surface using a Teflon mold and light-curing source. Shear bond strength (SBS) was assessed by using a digital universal testing machine, and failure modes were evaluated. Data were analyzed by analysis of variance (ANOVA) and least significant difference test. Results. A high significant difference in roughness and SBS was found amongst the tested groups P &lt; 0.001 . SBS and roughness for Group III were significant at P &lt; 0.05 , and the lowest value was observed in Group II. The cohesive mode of failure was dominant in Groups I and III, whereas adhesive failure was dominant in Group II. Conclusion. The surface treatment of porcelain with CO2 laser followed by HF application can enhance roughness and SBS, and can be recommended when extra retention during repair indication.

The effect of the corrosion inhibition of steel bar and the property of salt adsorption to salt adsorption type epoxy resin

Reinforced concrete structures in a salt-damaged environment are deteriorated by salt damage due to the influence of salt. As a repair measure, repair materials with salt adsorption performance and rebar rust prevention performance are used for inorganic materials. However, products with these added to organic materials are used for various purposes, which are used for various applications as repair materials. Unfortunately, there are few examples of its use becoming possible expected that measures against salt damage will be taken in various applications which have developed a “salt-adsorbing epoxy resin repair material” in which a salt-adsorbing agent is added to epoxy resin, which is an organic material. In addition, this research presented the salt adsorption effect and the corrosion inhibition effect on steel bars applied to each repair application.

Influence of surface treatment on repair bond strength of CAD/CAM long-term provisional restorative materials: an in vitro study

BackgroundThe surface treatment to improve the repair bond strength may vary because CAD/CAM provisional restoration polymers exhibit a variety of microstructures. This study was conducted to evaluate the effect of surface treatments on the repairability of three different CAD/CAM polymers for long-term provisional restorations.MethodsThirty specimens from each provisional restorative materials (CAD-Temp, Everest C-Temp, and PEEK) were divided into three groups: C: surfaces received no treatment; SB: surfaces were airborne particle abraded with 50 μm aluminum oxide; SB-T: surfaces received the same conditions as group SB in addition to thermocycling before and after treatment. Primer and nanohybrid repair resin composite were applied to the prepared CAD /CAM surfaces. The shear bond strength and the mode of failure were assessed. ANOVA and Tukey’s significant difference tests were used to evaluate the data.ResultsThe SB group had significantly higher repair SBS values (p < .001) compared to the other groups (C and SB-T). Everest C-Temp significantly recorded the highest repair SBS (17.84 ± 0.19 MPa) in group SB, while the lowest repair SBS values (5.51 ± 1.14 MPa) for CAD-Temp were recorded in group C. PEEK significantly recorded the second highest repair SBS (15.96 ± 0.18) in the SB group.ConclusionsEverest C-Temp had the highest repair SBS after an airborne abrasion particle. Thermocycling had no significant effect on the repair SBS for PEEK. Everest C-Temp and PEEK are recommended as long-term durable provisional materials for clinical use.

The Effect of Water Aging on the Repair Shear Bond Strength of Current Resin Composites

ABSTRACT Aims: We aimed to examine if water aging changes the repair bond strength of currently available resin composites. Subjects and Methods: Charisma (Kulzer, Hanau, Germany), Essentia (GC, Tokyo, Japan), and CeramX (Dentsply Sirona, North Carolina, USA) resin composites were prepared within acrylic resin cylinders (n = 22). The surfaces of all samples were polished with OptiDisc (Kerr, California, USA), and G-Premio BOND (GC, Tokyo, Japan) was applied to the surfaces. The G-aenial (GC, Tokyo, Japan) resin composite was formed on the adhesive-applied surface aided by a Teflon mold with a diameter of 2.38 mm and height of 2 mm and then polymerized with a LED light source (VALO Cordless, Standard mode; Ultradent, Utah, USA) for 20 s. All samples were kept in water for 1 day. To determine the shear bond strength, a universal test device (Marestek, İstanbul, Turkey) with a knife-edged metal tip was used at a speed of 1 mm/min. For the experimental group, the composite surfaces of the same samples were sanded with 180-grit silicon carbide sandpaper and then polished with OptiDisc (Kerr, California, USA). Samples were then kept in water for 6 months. Adhesive repair resin composite and shear test applications were performed similarly to the control group. Paired sample t-test, one-way ANOVA, and post hoc Tukey’s Honestly Significant Difference tests were performed for statistical analysis. For statistical significance, P &lt; 0.05 was accepted. Results: We observed repair shear bond strength values of 7.88 ± 3.20 MPa for Charisma versus 5.64 ± 3.08 MPa aged Charisma, 7.65 ± 2.64 MPa for Essentia versus 5.67 ± 3.10 MPa for aged Essentia, and 7.07 ± 3.22 MPa for CeramX versus 4.80 ± 2.28 for MPa aged CeramX. There was no difference within control groups nor in aged groups (P &gt; 0.05). However, bond strength was lower in aged composites (P &lt; 0.05). Conclusions: The repair bond strength of current resin composites decreases after 6 months of water aging. CLINICAL RELEVANCE TO INTERDISCIPLINARY DENTISTRY Repairing failed restorations is a common practice in a dental clinic. Repair of restorations is challenging, and our data suggests that the repair bond strength decreases with water aging for the tested resin composites, which are also widely used in clinics. In addition, using adhesive resin only as a surface preparation is insufficient. Therefore, clinicians are encouraged to optimise their treatment practices by considering these data.