Search Results (25)

Background/Objectives: Air particle abrasion (APA) is a common surface preparation method in dentistry, particularly for improving bond strength to dentin. This review evaluates the influence of APA on dentin adhesion. Methods: A systematic literature search from 2018 to 2023 was conducted according to PRISMA-ScR guidelines. Articles investigating the effects of APA on dentin adhesion using different particle types, sizes and adhesive systems were included. Data extraction included particle size, air pressure, outcomes tested and failure modes. Results: Fourteen primary studies met the criteria. Bioactive glass showed higher bond strength and more cohesive failures than alumina. Alumina particles (50 μm) bonded effectively in etch-and-rinse adhesive systems but failed more often in self-etch systems. Silica-modified alumina and mixed abrasive systems showed improvements in bonding performance. Optimal APA parameters were identified as 50 μm particle size, 60 psi (4 bar) air pressure and 5 s exposure time. Longer exposure times provided no additional benefit. Self-etch systems showed reduced bond strength compared to etch-and-rinse systems. Conclusions: This review looks at how particle type, size and air pressure affect dentin adhesion. Bioactive glass is a superior material due to its bond strength and reduced cytotoxicity. The optimal APA parameters are 50 μm particle size, 60 psi and 5 s. Etch-and-rinse systems are recommended for optimal adhesion. Further research is required on APA protocols and long-term durability. Full article

Dental adhesives play a crucial role in modern dentistry by enabling the bonding of diverse restorative materials to tooth surfaces. These systems have evolved through seven generations, each characterized by unique chemical compositions and application techniques. The advancements in dental adhesives have significantly impacted restorative dentistry by preserving tooth structure, enhancing aesthetics, and ultimately improving patient outcomes and treatment options. The choice of adhesive system depends on various factors, including the clinical scenario, material compatibility, and dentist preference. Ongoing advancements in adhesive technology continue to enhance treatment outcomes and streamline procedures for dental practitioners. The development of universal adhesives capable of functioning in both etch-and-rinse and self-etch modes has further simplified clinical protocols. This study is an observational cross-sectional study conducted among Romanian dentists. A questionnaire was distributed via email to Romanian dentists, encompassing seven questions that explored the predominant use of etch-and-rinse or self-etch adhesive systems, preferred adhesive types, and commonly encountered challenges in direct restorations. Statistical analyses were conducted using DATAtab version (2024). The study highlighted the varying preferences among Romanian dentists in selecting suitable adhesive agents. Etch-and-rinse (ER) techniques predominated in direct restorations, with universal adhesives being the most frequently used. Further investigation is warranted to delve into the preferences of Romanian dentists regarding the utilization of self-etch (SE), etch-and-rinse (ER), and universal adhesives (UAs). Full article

This study analyzed the dentin shear bond strength (SBS) of an etch-and-rinse (ER) or a self-etch (SE) adhesive incorporated with multifunctional polyhedral oligomeric silsesquioxanes (MA-POSS-8). An ER adhesive (Solobond Plus, VOCO GmbH, Cuxhaven, Germany) and a universal adhesive applied in SE mode (Scotchbond Universal, 3M, St. Paul, MN, USA) were infiltrated with MA-POSS-8 (Hybrid Plastics Inc., Hattiesburg, MS, USA) at 5 wt.% or 10 wt.%. Pure adhesives served as controls. Bovine dentin specimens were conditioned with one of the adhesives prior to the application of a nano-hybrid composite (Venus Diamond A3, Kulzer, Hanau, Germany). SBS and failure modes were determined after water storage for 24 h, 6 months, 12 months, or 24 months (each subgroup n = 20). Statistical analysis was performed using ANOVAs, Weibull statistics, and χ² tests (p < 0.05). SBSs for the control groups after 24 h were 17.4 ± 4.9 MPa for the ER adhesive and 19.1 ± 5.2 MPa for the universal adhesive. After 24 months, the SBS of the ER adhesive was significantly higher for 5 wt.% MA-POSS-8 (17.9 ± 5.1 MPa) than for the control group (14.6 ± 3.6 MPa) and 10 wt.% MA-POSS-8 (12.8 ± 4.1 MPa), and more cohesive failures were observed. The SBS of the universal adhesive increased during aging, irrespective of the MA-POSS-8 concentration. 5 wt.% MA-POSS-8 improves the SBS of the ER adhesive and does not impair the SBS of the SE adhesive. Full article

The effectiveness of a universal adhesive applied in three application modes for the preparation of Class V composite restorations was evaluated both clinically and by quantitative marginal analysis (QMA) over 36 months. In 50 patients, three (n = 21) or four (n = 29) non-carious cervical lesions (NCCL) were restored with Venus^® Diamond Flow (Kulzer GmbH, Hanau, Germany). The adhesive iBond^® Universal (iBU, Kulzer, Germany) was used in self-etch (SE), etch-and-rinse (ER), or selective-enamel-etch mode (SEE). The etch-and-rinse adhesive OptiBond^TM FL served as a control (OFL, Kerr GmbH, Herzogenrath, Germany). The restorations were clinically assessed (FDI criteria) at 14 days (BL), 6, 12, 24, and 36 months. Additionally, QMA was conducted on all restorations of 11 randomly selected patients. FDI criteria and marginal gap and perfect margin were compared between and within groups and recalls using McNemar, Wilcoxon, or Mann–Whitney U-tests (α = 0.05). Starting with 12 months, cumulative failure rates were lower in iBU-SE (0.0%, p = 0.016) and iBU-ER groups (2.1%, p = 0.07) compared to OFL (16.7%). At two years, iBU-SEE also showed fewer failures (0.0% SEE vs. 34.6% OFL, p = 0.016), as did iBU-SE compared to iBU-ER after 36 months (2.2 and 19.6%, p = 0.039). From BL, the iBU-SEE group always had the fewest marginal gaps and the highest percentage of perfect margins. From BL, iBU-SEE (0%, p = 0.008) and iBU-ER (0.2%, p = 0.027) showed significantly fewer marginal gaps compared to OFL (2.5%) and more perfect margins were found with iBU-SEE starting at 6 months (p = 0.054). The SEE and ER modes ensured the most excellent marginal quality, with differences from the control appearing earlier with QMA than clinically. In restoring NCCls, iBU showed superior clinical performance over OFL, especially in modes SE and SEE. Full article

The aim of this study was to investigate the effect of preceded tumor therapeutic irradiation on the tensile bond strength of three modern universal adhesives applied in self-etch mode on dentin. Specimens prepared from 135 extracted human third molars were divided into three superior groups. These received either no radiation, 5 Gy, or a total dose of 60 Gy in vitro irradiation, fractionally applied. The samples of each group were further randomly assigned to six subgroups to test three adhesives (Futurabond^® U, Voco; AdheSE^® Universal Ivoclar Vivadent; Xeno^® Select, Dentsply Sirona) in the self-etch application mode (n = 15). Tensile bond strength was determined using a universal testing machine (1.0 mm/min). Data were analyzed with ANOVA (p < 0.01) and Tukey’s test (p < 0.05). The influence of irradiation on the microtensile bond strength of the used dentin adhesives proved to be significant. For each material, a decrease in adhesion value was registered after irradiation. However, only for the material Xeno^® Select were significantly reduced adhesion values determined after irradiation with 60 Gy compared to 0 Gy. Within the limitations of an in vitro study, some effects of tumor therapeutic irradiation of human dentin on the tensile bond strength of universal adhesives used in self-etch mode could be observed. Those decreases were only partly significant, depending on the material and the radiation dose. Whether the tensile bond strength on irradiated dentin depends on the particular application mode (etch-and-rinse vs. self-etch) of the universal adhesives remains to be investigated. Full article

The composition of universal adhesives, as well as the adhesive strategy, may influence bonding effectiveness and durability. This study aimed to evaluate the microtensile bond strength (µTBS) and nanoleakage (NL), immediately and after 6-month aging, and in situ degree of conversion (DC), of two universal adhesives (Scotchbond Universal Adhesive, SBU; Xeno Select, XEN) applied with etch-and-rinse (ER) and self-etch (SE) strategies, in comparison with a two-step SE adhesive (Clearfil SE Bond, CSE). Dentin surfaces of fifty human third molars were randomly assigned to the following adhesives: two universal adhesives, SBU and XEN, applied in ER or SE mode and CSE, used as control. Teeth were sectioned into beams to be tested under µTBS, half of them after 24 h, and the rest after 6 months of water aging. Selected beams from each tooth were used for NL evaluation and in situ DC quantification. SBU and CSE showed significantly higher mean µTBS and lower nanoleakage than XEN, regardless of the evaluation time and adhesion strategy. XEN-SE yielded the lowest degree of conversion. Therefore, adhesive properties of universal adhesives to dentin are material dependent, regardless of the adhesion strategy, exhibiting XEN a significantly worse performance than SBU. Full article

Background and Objectives: The aim of this in vitro study was to evaluate the combined effect of a 2% chlorhexidine aqueous solution and a universal adhesive system applied in self-etch and etch-and-rinse strategies on the composite resin–dentin interface. Materials and Methods: Class V cavities were prepared on the facial and lingual surfaces of forty caries-free molars extracted for orthodontic reasons. The samples were randomly divided into two groups corresponding to the used etching protocol: I—etch-and-rinse; II—self-etch. In each tooth, one cavity was assigned for the control subgroups -IA (n = 20) and IIA (n = 20)—adhesive only, and the opposite cavity was pretreated with a 2% chlorhexidine solution—Gluco CHeX Cerkamed—subgroups IB (n = 20) and IIB (n = 20). Both sets of groups were restored using a universal adhesive system (Single Bond Universal Adhesive, 3M-ESPE) and a bulk-fill composite resin (Filtek One Bulk Fill Restorative, 3M-ESPE). The roots and the pulp tissue were then removed, and a needle connected to a perfusor with 100 mL saline solution was used for pulp pressure simulation with a hydrostatic pressure of 20 cm H₂O. Cariogenic attack was simulated using a demineralizing solution for 3 days at a constant temperature of 25 °C. The teeth were then sectioned in a facial-lingual direction and the microleakages at the occlusal and cervical margins were registered and scored using an optical Carl-Zeiss AXIO Imager A1m microscope (Carl-Zeiss). The composite resin–dentin interface was analyzed using a SEM Vega Tescan LMH II. Statistical analysis was performed using the Kruskal–Wallis test with a significance level of p < 0.05. Results: Microleakage evaluation showed no significant differences among the study groups (p > 0.05). In subgroup IA, significant differences were recorded between occlusal and cervical margins (p < 0.05). Conclusions: Application of chlorhexidine on tooth substrate before using a universal bonding system in total etch or self-etch mode has no influence on the adhesive interface in the condition of cariogenic attack. The thickness of the adhesive resin layer seems to be less uniform when using chlorhexidine, but the morphological differences at the adhesive interface have no influence on the sealing capacity of the universal bonding system, regardless of the etching strategy. Full article

Topical anesthetics are commonly used to minimize pain and anxiety during dental procedures. Research is scarce on the influence of topical anesthetics on bond strength. Thus, this research evaluated the effect of dentin contamination by topical anesthetic solution and gel on the micro-shear bond strengths of etch-and-rinse and self-etch bonding systems. Ninety transversally hemi-sectioned dentin discs were prepared and randomly assigned to three groups: no contamination (control group), contamination with topical anesthetic solution (Xylonor spray, Septodont), and contamination with topical anesthetic gel (Xylonor gel, Septodont). Each contamination group was subdivided into two subgroups (n = 15) based on whether the adhesive system was etch-and-rinse (Optibond Solo Plus, Kerr) or self-etch (Optibond XTR, Kerr). Tygon tubes with resin composite (Filtek Z350 XT, 3M ESPE) were placed on each surface and light cured. After 24 h, a universal testing machine was used to measure micro-shear bond strength (MPa). Furthermore, nine additional specimens of non-contaminated and contaminated dentin were prepared and scanned by a scanning electron microscope. The data of micro-shear bond strength were analyzed using two-way ANOVA, and narrative analysis was used to qualitatively interpret visual data of the micro-morphology of dentin from the scanning electron microscope. No significant differences in micro-shear bond strength among different contamination groups and adhesive systems were found (p > 0.05). The results are supported by micro-morphology of the treated dentin surfaces and modes of failure, as the micro-morphology was similar among contamination and control groups. There was no significant impact of topical anesthetic forms and dentin bonding systems on the micro-shear bond strength, which was supported by the micro-morphology from a scanning electron microscope. Full article

The effectiveness of a universal adhesive applied in different application modes for the preparation of Class V composite restorations was evaluated both clinically and by quantitative marginal analysis (QMA). In each of the 22 patients, four non-carious cervical lesions (NCCL) were restored with Filtek^™ Supreme XTE (3M). The adhesive Scotchbond^™ Universal (SBU, 3M) was applied in self-etch (SE), selective-enamel-etch (SEE) or etch-and-rinse (ER) modes. The etch-and-rinse adhesive OptiBond^™ FL (OFL, Kerr) served as a control. The restorations were clinically evaluated (FDI criteria) after 14 days (BL), 6, 12, 24, and 36 months. Additionally, QMA was conducted on all restorations of 11 randomly selected patients. The FDI criteria and marginal gap were statistically compared between the groups at each recall as well as for the time periods between recalls. The cumulative failure rate was non-significantly higher in the OFL group when compared to all of the SBU groups. Marginal adaptation in the OFL and SBU-SE/ER groups was significantly decreased (BL-36 m, p: 0.004) in comparison to the SBU-SEE group (BL-36 m, p: 0.063). More marginal gaps were found in the OFL group than in the SBU-SEE (BL to 36 m, p: 0.063–0.003) and SBU-ER (24/36 m, p: 0.066/0.005) groups as well as in the SBU-SE group when compared to the SBU-SEE (12–36 m, p_i ≤ 0.016) and SBU-ER (24/36 m, p: 0.055/0.001) groups. SBU-SEE performed most effectively. The clinical evaluation and QMA corresponded, yet QMA detected group differences earliest after 6 months and is thus a valuable extension to clinical evaluations. Full article

The purpose of this study is to compare bond durability, in terms of fatigue bond strength, of a two-step HEMA-free universal adhesive and representative adhesives in each systematic category. The adhesives used in this study were OptiBond FL, Prime&Bond NT, Clearfil SE Bond 2, G2-Bond Universal, and Scotchbond Universal Plus Adhesive. Fatigue bond strength testing and scanning electron microscopy analysis of adhesively bonded enamel and dentin interfaces were performed. For the adhesives in etch-and-rinse mode, the enamel fatigue bond strength of the G2-Bond Universal adhesive was significantly higher than those of other adhesives, and the dentin fatigue bond strength of Prime&Bond NT was significantly lower than the others. For adhesives in self-etch mode, the enamel fatigue bond strengths of Clearfil SE Bond 2 and G2-Bond Universal were significantly higher than that of the Scotchbond Universal Plus Adhesive, and the dentin fatigue bond strength of G2-Bond Universal was significantly higher than Clearfil SE Bond 2 and the Scotchbond Universal Plus Adhesive. The two-step HEMA-free universal adhesive showed higher enamel and higher or equal dentin fatigue bond strength than other selected representative adhesive systems in etch-and-rinse mode and higher or equal enamel and higher dentin fatigue bond strength than adhesive systems in self-etch mode. Full article

A vast number of adhesive formulations exist currently. However, available adhesives still have several drawbacks such as increased hydrophilicity, polymerization deficiency, potential cytotoxicity and limited monomer interdiffusion within dentin. To improve material properties, a Bisphenol A-free adhesive containing a novel dendrimer G(2)-isocyanatoethyl methacrylate (G-IEMA) in replacement of Bis-GMA was made and tested. Sound human molars were sectioned to expose mid-coronal dentin, which was bonded using four adhesives—Futurabond, Scotchbond Universal and experimentals EM1 and EM2. The experimental adhesive EM2 contained G-IEMA, while EM1 had Bis-GMA. Groups were further allocated to two different adhesive strategies: etch-and-rinse (20 s etching) or self-etch. Immediate (24 h) microtensile bond strength to dentin (n = 5) was tested using a universal testing machine (1 mm/min, 5 kN; Shimadzu AGS-X Autograph, Tokyo, Japan), while the ultrastructure of the interface (n = 2) was assessed using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS). Nanoleakage expression was evaluated using silver nitrate penetration and posterior SEM-EDS analysis (n = 3). Linear mixed models/Generalized models were used for inferential statistics (5% significance level). Bond strength results did not depend on the adhesive choice, although differences were found between strategies (p < 0.001). Regarding nanoleakage, when applied in an etch-and-rinse mode, experimental adhesives scored lower nanoleakage means than Futurabond and Scotchbond Universal. The novel adhesive shows interesting interfacial properties, with favorable nanoleakage results and a bond strength to dentin that matches current commercial adhesives. Full article

Saliva contamination of etched enamel before sealant application is the most common reason for failure of fissure sealants, thus affecting the effect of caries prevention. This study aimed to evaluate the shear bond strength (SBS) and microleakage of resin-based fissure sealant on saliva-contaminated etched enamel after rinsing, re-etching, and applying universal adhesive. Fifty human third molars were sectioned into 2 parts and embedded in acrylic resin to obtained 100 samples. The samples were randomly assigned to 5 groups: 1, etching; 2, etching + contamination; 3, etching + contamination + rinsing; 4, etching + contamination+ re-etching; 5, etching + contamination + universal adhesive. Each group was divided into 2 subgroups: 24 h storage and 5000× thermocycling. After measuring SBS, failure mode was analyzed. In an additional 15 teeth, microleakage was tested using dye penetration method. Three more teeth were used for scanning electron microscope (SEM) observation of the enamel surface morphology in each group. The adhesive group had significantly higher mean SBS after 24 h storage, while the re-etching group were better after 5000× thermocycling. The etching, etching+ contamination+ re-etching, and etching+ contamination+ universal adhesive groups showed the least microleakage. The SEM reveals considerable variations in the enamel surface appearance within groups. Re-etching or applying universal adhesive in saliva-contaminated etched enamel before sealant can achieve satisfactory results. Considering the less operative steps and the shorter chair time, applying universal adhesive is more recommended for a pediatric patient if saliva-contamination happened before sealant application. Full article

In the present study, we evaluated the influence of bovine enamel exposure to acidic drinks (Coca-Cola, Coca-Cola Company, Milano, Italy, pH = 2.37) on shear bond strength of three sealants (Fissurit; Grandio Seal and Admira Fusion—Voco Gmbh, Cuxhaven, Germany). For each sealant, two adhesive techniques were tested to investigate the impact of the adhesive application on shear bond strength of sealants after immersion in acidic drink and in the control: Group 1—Control: enamel surface was not in contact with acid drinks, acid etching application and self-adhesive technique for fissure sealant; Group 2—enamel surface was not in contact with acid drinks, acid etching, and adhesive applications, an etch-and-rinse technique for fissure sealant; Group 3—enamel surface was immersed in acid drink, acid etching application and self-adhesive technique for fissure sealant; Group 4—enamel surface was immersed in acid drink, acid etching, and adhesive applications, an etch-and-rinse technique for fissure sealant. For each specimen, the sealant composite resin was applied to the enamel surface and tested with a universal testing machine. Shear bond strength was measured in MPa and with an optical microscope to determine failure modes, quantified with adhesive remnant index (ARI). Enamel acidification variably influenced bond strength values of the different sealants. When no enamel pretreatment was applied, no significant differences were found among the sealants (p > 0.05). However, the mere application of acid etching without adhesive procedures resulted in lower bond strength (p < 0.001). The acid pretreatment affected significantly the bond strength of all sealants tested (p < 0.001), but no significant differences were recorded between the subgroups. Full article

This prospective, double-blind, six-arm parallel randomised controlled trial aimed to compare the performance of two universal adhesives (UAs) in non-carious cervical lesions (NCCLs), using the FDI criteria, and analysed if participants/NCCLs’ characteristics influenced the outcome. Thirty-eight 18- to 65-year-old participants were seeking routine dental care at a university clinic. At baseline, 210 NCCLs were randomly allocated to six groups (35 restorations’ each). The UAs tested were FuturabondU (FBU) and AdheseUniversal (ADU) applied in either etch-and-rinse (ER) and self-etch (SE) modes. FuturabondDC (FBDC) in SE and in SE with selective enamel etching (SE-EE) modes were controls. NCCLs were restored with AdmiraFusion. The analysis included nonparametric tests, Kaplan-Meier and log-rank tests (α = 0.05). At 2-years, of 191 restorations, ten were missed due to retention loss (all groups, p > 0.05). FBDC (p = 0.037) and FBU (p = 0.041) performed worse than ADU in SE mode. FBDC and FBU also showed worse functional success rate (p = 0.012, p = 0.007, respectively) and cumulative retention rates (p = 0.022, p = 0.012, respectively) than ADU. Some participants/NCCLs’ characteristics influenced (p < 0.05) the outcomes. FBU did not perform as well as ADU, especially in SE mode and due to functional properties. Participants’ age and NCCLs’ degree of dentin sclerosis and internal shape angle influenced FBU performance. Full article

Objectives: The aim of this study was to evaluate the effect of different enamel surface treatments on the micro-shear bond strength. Materials and methods: Sixty-four approximal surfaces from freshly extracted molars were randomly assigned to eight groups, according to combinations of the following enamel surface treatments: ground or unground, 37.5% phosphoric acid etching time of 15 or 30 s, and with or without primer application. The same bonding agent (Optibond FL™ Adhesive, Kerr) was then used for all groups, and a 1.8 mm diameter resin composite (Harmonize™, Kerr) cylinder was built up on the bonded surface. Samples underwent a shear force test at a crosshead speed of 1 mm/min until failure. Bond strength was calculated, and failure modes were inspected under an optical microscope. Results: Bond-strength values ranged from 8.2 MPa for 15 s etched unground enamel with primer application to 19.6 MPa for 30 s etched ground enamel without primer application. ANOVA and Fisher’s LSD post hoc tests revealed significant differences between the groups. Conclusions: Etching time and grinding have a statistically significant effect on the micro-shear bond strength of a three-step etch-and-rinse adhesive system on enamel. Primer application does not seem to be beneficial for enamel adhesion. Full article