Self-etch Adhesives Research Articles

Influence of Application Modes on Increasing Bond Strength Longevity of Self-etching and Universal Adhesive Systems to Enamel.

The present study aimed to evaluate the influence of application mode on the short-term microshear bond strength longevity of self-etching and universal adhesive systems to enamel, the failure mode, and the resulting enamel surface micromorphology. Ninety enamel surfaces were obtained from sound third molars, planed, and randomly assigned to nine groups, according to the application mode and the adhesive system (n=10). There were three primer application modes: according to the manufacturer's recommended application time (control), using double the application time recommended for the primer and selective enamel etching. The adhesive systems used were: Clearfil SE Bond (Kuraray), FL-Bond II (SHOFU), and Futurabond U (Voco). At least two resin-bonded composite cylinders (Grandioso Light Flow, Voco) were placed on each enamel surface, and then evaluated for microshear bond strength at 24 hours and 180 days of storage in solution body fluid (SBF) at pH 7.4. Failure modes were evaluated with a stereoscopic microscope at 20× magnification. A micromorphological analysis of the enamel surface was performed under a scanning electron microscope at 5000× magnification before and after the treatments. Mixed models for repeated measures over time showed significant interaction among application modes, adhesive systems, and time periods (p=0.0331). The bond strength of FL-Bond II adhesive to enamel observed after performing selective enamel etching was significantly higher than that observed after applying the control treatment (p=0.0010) at both 24 hours and 180 days. However, no significant difference was observed between the application of this same adhesive at double the time recommended by the manufacturer and the other two application modes (p>0.05). There was also no significant difference in the microshear bond strength for the enamel treatments applied using Clearfil SE Bond and Futurabond U (p>0.05). A significant reduction in bond strength to enamel was observed at the 180-day storage time for all the adhesive systems when selective enamel etching was performed (p<0.0001). No significant association was observed between the adhesive system failure mode and the enamel treatments (p=0.1402 and p=0.7590 for 24 hours and 180 days, respectively). The most prevalent failure was the adhesive type.

Comparative Evaluation of the Microleakage of Self-etch Adhesives on the Pulp Chamber Dentin after Proanthocyanidin Application: An In vitro Study

ABSTRACT Background: The long-term success of adhesive restorations is contingent on minimizing microleakage, which can lead to postoperative sensitivity and secondary caries. Sodium hypochlorite (NaOCl) and ethylenediaminetetraacetic acid (EDTA) irrigation are commonly employed during adhesive restorative procedures, but their impact on microleakage remains a concern. Proanthocyanidin (PA), a naturally derived agent, has shown potential in enhancing bond strength. Aim: This study aimed to compare and evaluate the effect of treatment with or without 30% PA of the pulp chamber dentin after 1% NaOCl and 17% EDTA irrigation on the microleakage of adhesive restorations. Materials and Methods: Forty caries-free, freshly extracted permanent human molars were used. The pulp chamber roof was removed, and the roots were resected. Canal orifices were enlarged and sealed. Specimens were divided into four groups based on adhesives (OptiBond All-In-One and Adper Easy One) and irrigation regimens. After irrigation, pulp chambers were restored with Filtek Bulk-Fill composite resin. Microleakage was assessed using methylene blue dye penetration. Results: Microleakage was observed in all groups, irrespective of irrigation protocol and adhesives. PA application showed reduced dye penetration compared to without PA, although not statistically significant. Statistical analysis was performed using Kruskal–Wallis and Mann–Whitney tests at P &lt; 0.05. Conclusion: Irrigation protocols and the use of PA had no significant effect on the microleakage of self-etch adhesives to pulp chamber dentin. A 1-min application of 30% PA solution after NaOCl and EDTA irrigation did not improve the bonding of self-etch adhesives to pulp chamber dentin.

Comparison of tensile strength in resin-retained cores with pins and adhesives

The resistance of resin-reconstructed cores is crucial for the durability of dental restorations. The study aimed to compare the tensile strength of resin cores retained by interdentinal pins and adhesive agents. Forty human first premolars were used, divided into four groups of 10, utilizing screwed interdentinal pins, cemented interdentinal pins, and fifth and sixth-generation adhesive agents. The results indicated that cemented interdentinal pins combined with sixth-generation adhesive agents provided the highest tensile strength (22.77 MPa), followed by total-etch adhesives (20.94 MPa), self-etch adhesives (16.46 MPa), and screwed interdentinal pins (13.44 MPa). It is concluded that the use of cemented interdentinal pins and advanced adhesive agents is superior, suggesting the need for an interdisciplinary approach to improve the effectiveness of dental restorations

Performance of self-etching adhesives on caries-affected primary dentin treated with glutaraldehyde or silver diamine fluoride

Objectivesto evaluate the quality and stability of adhesive interfaces established by self-etching adhesives on caries-affected primary dentin (CAD) treated with glutaraldehyde (GA) or silver diamine fluoride (SDF). Methods42 primary molars were exposed to a microbiological caries-inducing protocol and divided into 6 groups according to the adhesive system (Clearfil SE - CL or FL Bond II - FL) and pretreatment (water, GA or SDF) applied on CAD. One tooth from each group was analyzed for surface modification using infrared spectroscopy. Crowns were restored with resin composite (n = 36) and cut into beams and slices. The beams were subjected to microtensile testing, Raman spectroscopy and SEM after 24 h and 6 months of storage. The slices were analyzed using Micro-Raman spectroscopy to determine the diffusion zone thickness (DZ) in each period. Data were analyzed by ANOVA and Tukey or Kruskal-Wallis and Dunn tests (α = 0.05%). ResultsSDF reduced the immediate bond strength for both adhesives. The control groups showed a decrease in BS after 6 months in artificial saliva. GA increased immediate DZ for FL, while SDF had the opposite effect on CL. GA decreased the DZ for FL at 6 months. There was a predominance of adhesive failures with areas of cohesive dentin fractures within control groups. SignificanceModifications caused by dentin surface treatments may directly affect the performance of adhesive systems and the quality and stability of adhesive restorations.

In vitro performance of an autocured universal adhesive system in bonding to dentin

BackgroundThe successful integration of resin-based dental adhesives significantly impacts restorative dentistry, providing efficient and aesthetically pleasing caries treatments. Among various adhesives, one-step self-etching adhesives (1-SEAs) have gained popularity due to their simplicity and short application time. However, concerns have been raised regarding their bonding performance and marginal adaptation characteristics, which differ from two-step self-etching adhesives (2-SEAs) and three-step etch-and-rinse adhesives. Additionally, light-cured bonding materials may encounter challenges in deep cavities and inaccessible areas, necessitating extended light irradiation time. Autocured bonding materials are a potential solution, but limited comparative studies have been conducted on their performance.MethodsIn this in vitro study, we evaluated a new autocured universal bonding material (Bondmer Lightless 2) and compared the results with recent light-cured bonding materials. Microshear bond strength (μSBS) tests were performed on 25 human molars using five different combinations of adhesives and composite resins: Bondmer Lightless 2 with Estelite Bulk Fill Flow (BE group), Bondmer Lightless 2 with a prototype composite resin (BO group), Prime&Bond Universal with SDR flow + (PS group), Scotchbond Universal with Filtek Bulk Fill (SF group), and G-Premio Bond with Gracefil BulkFlo (GG group). The bond strengths and failure modes were assessed using a universal testing machine and scanning electron microscope (SEM), respectively. Marginal adaptation was evaluated using swept-source optical coherence tomography (SS-OCT) and confocal laser scanning microscopy (CLSM) on 40 sound bovine maxillary incisors.ResultsThe μSBS test showed no significant differences in bond strength among the tested groups. Most failure modes were observed at the bond interface between the adhesive and the dentin. The autocured bonding material demonstrated significantly higher marginal adaptation (SI%) than PS, SF, and GG. The CLSM images corresponded with gaps observed in the SS-OCT images, indicating improved marginal sealing in the autocured group.ConclusionsThe new autocured universal bonding material exhibited comparable bond strength to a conventional light-cured material while demonstrating a superior marginal adaptation level. This finding suggested that the autocured material could be a valuable alternative, especially when extended light irradiation would pose a challenge. Further clinical studies would be warranted to evaluate the performance of the autocured bonding material in actual restorative dental practice.

The Effect Of Er,Cr:YSGG Laser Conditioning on Dentin Bond Strength and Nanoleakage of Universal Adhesive Systems: An In Vitro Study.

To investigate the effect of erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser conditioning on dentin bond strength and nanoleakage of different universal and self-etch adhesives. A total of 84 intact human third molar teeth were cut at the dentin level, and half of them were laser conditioned. The specimens were divided into three groups; two different universal resins and one self-etch adhesive resin were applied and composite resin restorations were created. For the microtensile bond strength (µTBS) test, 20 microspecimens were prepared from the laser and control group of each adhesive (n = 20) and tested with a universal device. For nanoleakage observation, 10 specimens were prepared from each group (n = 10) and stored in silver nitrate solution, and then the amount of nanoleakage was analyzed by field emission scanning electron microscopy (FESEM). Data were analyzed with two-way ANOVA, Tukey's honestly significant difference, and chi-square tests. The mean dentin bond strength of all adhesives in the laser groups was found to be statistically significantly lower than those of the control groups (P < .05). No difference was found between the mean bond strength of the adhesives in the laser and control groups (P > .05). Higher nanoleakage was observed in all adhesives in the laser groups compared to the control groups (P < .05). Irradiation of the dentin surface with Er,Cr:YSGG could adversely affect the µTBS and nanoleakage, likely by affecting the structure of the hybrid layer.

Enhancing bond stability: impact of adhesive thinning on resin-dentin bonded interfaces.

This study aimed to investigate the effect of adhesive thinning on resin-dentin-bonded interfaces created by two simplified adhesives. Micro-tensile bond strengths and interfacial nanoleakage were evaluated within bonded dentin interfaces formed by Adper Single Bond 2 and Single Bond Universal after 24 hours and 6 months of water storage. The adhesives were subjected to three different techniques: air-thinning, brush-thinning, or application without thinning. Statistical analysis was performed using a multi-level analysis of variance followed by Bonferroni's post-hoc test, at a significance level of 0.05. Adper Single Bond 2 demonstrated the highest immediate microtensile bond strengths (43.5 ± 1.3 MPa) and the lowest immediate nanoleakage (49.8 ± 2.8%) when air-thinning was employed. Single Bond Universal exhibited the lowest nanoleakage (36.4 ± 1.8%) when air-thinning was used, although there was no significant difference in immediate bond strengths between air-thinning and brush-thinning approaches, which both showed higher values compared to the no-thinning approach. After 6 months of storage, a significant decrease in bond strengths and a significant increase in nanoleakage were observed across most groups (p < 0.001). While all groups displayed varying degrees of instability over a 6-month storage period, air-thinning of simplified etch-and-rinse and self-etch adhesives proved to provide clinically acceptable bonded interfaces. The findings suggest that adhesive thinning techniques can play a vital role in enhancing bond stability and longevity in resin-dentin-bonded interfaces.

Effect of Laser Etching Versus Self-Etching Adhesive and Conventional Acid-Etching Techniques on Shear Bond Strength, Microleakage and Penetration Depth of a Resin Based Pit and Fissure Sealant (An In Vitro Study)

Effect of Laser Etching Versus Self-Etching Adhesive and Conventional Acid-Etching Techniques on Shear Bond Strength, Microleakage and Penetration Depth of a Resin Based Pit and Fissure Sealant (An In Vitro Study)

Evaluation of biocompatibility of four different one-step self-etching adhesives by animal experimental method

Aims: The success of materials used in dentistry is closely related to their biological safety. In recent years, there has been growing concern about the biocompatibility of self-etch adhesives, which are frequently used in restorative dental treatment. The aim of this study is to compare the biocompatibility of four different single-stage self-etch adhesive materials (Prime &amp; Bond One Select, Optibond All-in-One, Clearfil Universal Bond, and Single Bond Universal) with the animal test method and evaluate them histopathologically. Methods: The experimental materials were polymerized by filling 10 mm-long, 2 mm-diameter polyurethane tubes. For each adhesive, 21 tubes were used. The tubes were placed in the subcutaneous pockets formed by four different incisions in the backs of 21 adult male albino rats. On the 7th, 30th, and 60th days, rats were randomly divided into three groups. At the end of these durations, the tube and the surrounding 2 cm2 of tissue were excised together. The sections were taken into preparation and stained with hematoxylen and eosin. The severity of inflammation, inflammatory cell count, and fibrous capsule thickness were evaluated histologically by light microscopy. Results: On the 7th day of samples, lesions due to acute inflammation, edema, and PMNL infiltration were observed. In the 30th-day samples, it was observed that inflammation decreased against all materials and fibrocollagen tissue increased. On the 60th day, granulation and fibrous tissue increased due to regeneration and reparation processes. On the 60th day, the number of inflammatory cells decreased significantly compared to the 7th day. When the fibrous tissue formation was evaluated, it was found that the 7th day score was significantly lower than the 60th day score. Conclusion: The severity of the inflammatory reaction at the beginning of all materials can be explained by the effects of residual monomer release and surgical trauma.

A scanning electron microscope-based comparative evaluation of resin tag formation at the resin dentin inter-diffusion zone

Aim of study was evaluate and compare the formation of the resin dentin interdiffusion zone (RDIZ) at the radicular dentin and resin interface after etching with phosphoric acid (PA) and glycolic acid (GA), using either light-cure and self-cured adhesives. Twenty extracted teeth were root canal treated. Post space preparation was done, and the samples were randomly divided into two main groups depending upon the etchant. Each group was further divided into two subgroups depending on the type of adhesive used. One group was etched with 37% PA (Prime® Dental Products PVT LTD, India) and the other with 35% GA (Glycolic 35 Peel, Rejsol, India). Etching was followed by the application of light-cured adhesive (3M ESPE Adper Single Bond, USA) or self-etch (3M ESPE Single Bond Universal, Germany). Fibre posts were then placed and after a coronal build-up, the teeth were sectioned longitudinally and observed under SEM. Statistical analysis: Data was analyzed by descriptive statistics as a percentage of resin tag density for all the groups. The Kruskall-Wallis test was applied for overall comparison and a Mann-Whitney U test for inter-group analysis. Resin tag density was found to be the highest in the coronal third followed by the middle third of radicular dentin and was the least in apical thirds for both groups. Resin tag density was similar for light cure and self-etch adhesives in the coronal, middle, and apical thirds of both groups. In conclusion this study concluded that GA could be thought of as a potential etchant for the radicular dentin.

The Effect of Salivary Contamination on the Shear Bond Strength of Seventh- and Eighth-generation Adhesive Systems.

To compare the effect of salivary contamination on the shear bond strength (SBS) of seventh- and eighth-generation adhesives. Specimens were randomly divided into group I and group II, subdivided into three subgroups of 11 samples. Subgroup IA-seventh-generation uncontaminated (control); adhesive; air-dried; light cured. Subgroup IB-seventh-generation adhesive; saliva application, air-dried; light cured. Subgroup IC-seventh-generation adhesive; saliva application, air-dried, reapplication of adhesive, air-dried, light cured. Subgroup IIA- eighth-generation uncontaminated (control); adhesive, air-dried; light cured. Subgroup IIB- eighth-generation adhesive; saliva application, air-dried; light cured. Subgroup IIC-eighth-generation adhesive, saliva application, air-dried, reapplication of adhesive, air-dried; light cured. Following bonding procedure, composite resin restoration was done and subjected to SBS analysis. Mean SBS of eighth-generation adhesive was higher compared to seventh with and without saliva contamination. Reduction of SBS in seventh- and eighth-generation after saliva contamination was regained by reapplication of adhesive, which was less compared to the control [statistically significant (p < 0.05) for seventh and statistically not significant for eighth-generations]. The eighth-generation adhesives show better SBS with and without saliva contamination and reapplication of eighth-generation adhesives significantly improved the SBS close to the control. Single-step self-etch adhesives are the adhesives which are currently used for bonding composite restorations to dentin. The adhesive bond strength can be adversely affected by moisture contamination, especially by saliva, which can lead to failure of restoration. So, it is imperative to study a material which gives better bond strength and is less affected by salivary contamination and effect of decontamination to regain the bond strength. The study concluded that eighth-generation adhesives showed higher mean SBS with and without saliva contamination and reapplication of eighth-generation adhesives significantly improved the bond strength close to the control group. Mohan MC, Geetha P, Soman D, et al. The Effect of Salivary Contamination on the Shear Bond Strength of Seventh- and Eighth-generation Adhesive Systems. Int J Clin Pediatr Dent 2023;16(S-1):S63-S66.

Cyclic shear fatigue of orthodontic brackets bonded to enamel using self-adhering flowable composites

BackgroundSelf-adhering composites are claimed to bond to teeth without prior acid etching and bonding steps. This study aimed to evaluate the cyclic shear fatigue (CSF) of metal orthodontic brackets bonded to enamel using self-adhering flowable composites (Constic and VertiseTM Flow) in comparison with that of total-etch and self-etch adhesives. Materials and methodsTwenty-five human premolars comprising 100 surfaces were randomly divided into four groups (n = 25): total-etch, self-etch, Constic, and VertiseTM Flow. A total of 10 surfaces were used per group for baseline static shear bond strength (SSBS) evaluation and 15 surfaces for CSF evaluation. Each tooth was treated with the four bonding agents. Both SSBS and CSF were evaluated using a universal testing machine. For CSF, the staircase method was used with an initial pulling load equivalent to 60% of the SSBS of each group for 1000 cycles or until failure. The adhesive remaining index (ARI) was evaluated for surviving samples using a stereomicroscope. Statistical analysisA one-way ANOVA with Tukey’s post hoc test was used to analyze the CSF data, and a chi-square test was used to analyze the ARI. ResultsThe total-etch adhesive showed significantly higher CSF values than that of the other groups (p < 0.001). Both total-etch (10.78 ± 0.31 MPa) and self-etch (6.75 ± 0.91 MPa) adhesives showed significantly higher CSF than did Constic (1.94 ± 0.31 MPa) and VertiseTM Flow (2.01 ± 0.25 MPa), (p < 0.001). The ARI indicated that more resin remnants were observed with the total-etch and self-etch adhesives than those with the self-adhering flowable composites. However, no significant differences were observed among groups (p > 0.05). ConclusionsTotal-etch and self-etch adhesives showed satisfactory bond strengths for orthodontic treatment. However, Constic and VertiseTM Flow self-adhering flowable composites may not be clinically sufficient for bonding metallic orthodontic brackets to enamel.

Effect of Self-Cured and Self-Etch Adhesive Systems on Shear Bond Strength After Photodynamic Therapy and Disinfection with Different Types of Lasers

Effect of Self-Cured and Self-Etch Adhesive System on Shear Bond Strength After Photodynamic Therapy and Disinfection with Different Types of Lasers&#x0D; &#x0D; Ayşe Çeşme1-a*, Ihsan Hubbezoğlu1-b&#x0D; 1 Sivas Cumhuriyet University, Faculty of Dentistry, Department of Restorative Dentistry Sivas, Türkiye.&#x0D; &#x0D; ABSTRACT &#x0D; Objectives: The aim of this study was to investigate the strength of shear bonding of self-cured and self-etch adhesive systems to dentin after surface disinfection with Photodynamic Therapy (PDT), Er:YAG, Nd:YAG, and KTP laser.&#x0D; Materials and Methods: In the study, 6 main-groups were formed as Control, Er:YAG Laser, Nd: YAG Laser, KTP Laser, KTP Laser activated PDT and Diode Laser activated PDT. Each group was divided into two subgroups; Self-cured (Tokuyama Universal) and self-etch (Scotchbond Universal) adhesive system(n=10). 120 molar teeth were prepared to expose dentin surfaces. After disinfection and adhesive application, nanohybrid composite resin with a diameter of 3 mm and a height of 2 mm was applied to the dentin surface with the help of transparent molds. All samples were thermally cycled 5.000 times at 5°C and 55°C. Shear bond strength (SBS) test was applied to the samples in a universal test device.&#x0D; Results: The differences between the Er:YAG laser group and the control, KTP and Nd:YAG laser groups of the self-cured adhesive samples were statistically significant. While the differences between the Nd:YAG laser group and the PDT groups were statistically significant (p

Micro Tensile bond strength and microleakage assessment of total-etch and self-etch adhesive bonded to carious affected dentin disinfected with Chlorhexidine, Curcumin, and Malachite green

Assessment of micro tensile bond strength (microTBS) and micro-leakage scores of total-etch adhesive (TAE) and self-etch adhesive (SAE) bonded to carious affected dentin (CAD) sterilized using different cavity disinfectant (curcumin photosensitizer (CP) and malachite green (MG) and Chlorhexidine (CHX) in comparison to no disinfection (ND) control group. One hundred and twenty human molars having International Caries Detection and Assessment System (ICDAS) scores of 4 and 5 were included. Visual inspection, dental explorer hardness testing, and caries detector solution using 5% basic Fuchsin dye solution was applied to dentin to identify the CAD surface. All the specimens were divided into four groups (n = 30) according to the cavity disinfectants used. Group A: 2% CHX, Group B: CP, Group C: MG, and Group D: ND. Each group was further divided into two subgroups (n = 15) based on the adhesion protocol. Groups A1, B1, C1, and D1 were held using TEA, and groups A2, B2, C2, and D2 were adhered using SEA system. The composite material was then built in 2 mm increments and then cured with light. MicroTBS and failure mode assessment using a universal testing machine (UTM) and stereomicroscope at a 40X magnification was performed on 10 samples from each subgroup. The microleakage assessment was performed using a dye penetration test on five samples from each group. ANOVA and Tukey post-hoc tests were used to compare means and standard deviation (SD) of bond strength and microleakage (p < 0.05). RESULTS The maximum microTBS was displayed by A1= CHX and TEA (13.28± 1.01 MPa). The lowest bond scores were demonstrated by C2= MG and SEA (5.98±0.44 MPa). The highest micro-leakage was exhibited by C1= MG and TEA (58.32 ± 2.11 nm). Whereas, the lowest micro-leakage values were displayed by A2= CHX and SEA (24.34± 1.11 nm). Chlorohexidiene displayed better bond strength and the lowest microleakage scores with Total-etch adhesive and Self-etch adhesives when used as a cavity disinfectant. Total-etch adhesives performed better in terms of microTBS scores whereas self-etch adhesives displayed superior seal ability within the same disinfectant group.

The Use of Warm Air for Solvent Evaporation in Adhesive Dentistry: A Meta-Analysis of In Vitro Studies

Any excess solvent from dental adhesive systems must be eliminated prior to material photopolymerization. For this purpose, numerous approaches have been proposed, including the use of a warm air stream. This study aimed to investigate the effect of different temperatures of warm air blowing used for solvent evaporation on the bond strength of resin-based materials to dental and nondental substrates. Two different reviewers screened the literature in diverse electronic databases. In vitro studies recording the effect of warm air blowing to evaporate solvents of adhesive systems on the bond strength of resin-based materials to direct and indirect substrates were included. A total of 6626 articles were retrieved from all databases. From this, 28 articles were included in the qualitative analysis, and 27 remained for the quantitative analysis. The results of the meta-analysis for etch-and-rinse adhesives revealed that the use of warm air for solvent evaporation was statistically significantly higher (p = 0.005). For self-etch adhesives and silane-based materials, this effect was observed too (p < 0.001). The use of a warm air stream for solvent evaporation enhanced the bonding performance of alcohol-/water-based adhesive systems for dentin. This effect seems to be similar when a silane coupling agent is submitted to a heat treatment before the cementation of a glass-based ceramic.

Evaluation of gap formation for different adhesive agents in primary teeth with optical coherence tomography.

This study aimed to evaluate gap formation between the tooth surface and restorative material in terms of microleakage by using optical coherence tomography (OCT) for self-etch and selective-etch applications of two different universal and one self-etch adhesives. Sixty non-caries, primary molar teeth were divided into six groups; self-etch and selective-etch application ways of two different universal and one self-etch adhesive systems (n:10). After Class-V cavities were prepared, every tooth was distributed randomly in groups to apply adhesion procedure and then, all cavities were restored with polyacid-modified composite resin. Microleakage was evaluated by measuring the gap between the tooth surface and restoration by a blind researcher with Image J Software from OCT images. During statistical analysis, the significance level was accepted as p<0.05. According to the statistical analysis of the measurements obtained by Image J Software, selective-etch groups showed less gap formation than self-etch groups for each tested adhesive (p<0.05), and self-etch adhesive without etching showed significantly highest gap formation among all groups (p<0.05). Universal adhesives with a selective-etching step might be preferred over self-etch adhesives for long-lasting polyacid-modified composite resin restorations in primary teeth. However, obtained results should be considered with another prospective clinical study for long-term prognosis.

Chlorhexidine-loaded bioactive glass for incorporation into adhesive systems: Mechanical properties, antibacterial activity, cell viability, and hydroxyapatite precipitation

AimTo evaluate the effect of chlorhexidine-functionalized bioactive glass (45S5) addition on mechanical and bioactive properties of experimental self-etching adhesives. Material and methodsThe bond of two-step self-etching adhesives were used in the following groups: (1) Magic Bond (commercial control – hydrophobic adhesive); (2) Experimental bond without bioglass (experimental control); (3) Experimental bond + 5% 45S5 glass (wt%); (4) Experimental bond + 20% 45S5 glass (wt%); (5) Experimental bond + 5% chlorhexidine-functionalized 45S5; (6) Experimental bond + 20% chlorhexidine-functionalized 45S5. Hourglass-shaped specimens were made to obtain data on mechanical properties (cohesive strength and elastic modulus). Adhesive discs were made for bacterial activity evaluation using Streptococcus mutans UA159 biofilms. The materials’ cell viability (%) was tested using the MMT assay technique. For the evaluation of mineral precipitation, adhesive discs were made, kept in PBS for 28 days and used for SEM/EDS analyses. ResultsThe 45S5 CHX group (20%) presented the lowest values of mechanical properties (p < 0.001). On the other hand, only groups containing 45S5 previously functionalized with chlorhexidine, in any of the concentrations tested, were able to prevent biofilm formation (p < 0.001). None of the tested adhesives presented cytotoxicity, being similar to the commercial negative control (p > 0.05). SEM and EDS analyses revealed the functionalization of 45S5 bioactive glass with chlorhexidine did not impair the bioactivity of the newly developed adhesive systems. ConclusionDespite reducing some mechanical properties of the experimental adhesive system, the functionalization of bioglass particles with chlorhexidine reduces biofilm formation, does not compromise its biocompatibility, and maintains the mineral precipitation.

Effect of different adhesive systems on dental defects and sensitivity to teeth in composite resin restoration: a systematic review and meta-analysis.

This meta-analysis aimed to elucidate the effects of various acid etching patterns on the sensitivity of teeth and their clinical effectiveness following composite resin repair. PubMed, Cochrane Library, Web of Science, and Embase databases were searched for relevant studies on the postoperative sensitivity (POS) of composite resin restorations after using different bonding systems. The retrieval was from the inception of the databases to August 13, 2022, with no filter of written language. Literature screening was conducted by two independent researchers. The Cochrane risk-of-bias assessment tool was adopted for quality evaluation, and Stata 15.0 for analysis. Twenty-five randomized controlled trials were included in the present study. Following resin composite restoration, 1309 restorations were bonded by self-etching (SE) adhesives, whereas 1271 restorations were bonded by total-etching (TE) adhesives. The meta-analyses showed that there is no evidence to prove the SE and TE will affect POS at present when measured using the modified United States Public Health Service (USPHS) criteria [RR = 1.00 (95% CI: 0.96, 1.04)], the World Dental Federation (FDI) [RR = 1.06 (95% CI: 0.98, 1.15)], or the visual analog scale (VAS) [SMD = 0.02 (95% CI: -0.15, 0.20)] scales. At a certain follow-up time, TE adhesives provide better outcomes in terms of color match, marginal staining, and marginal adaptation. In other words, TE adhesives have better esthetic results. The type of bonding technique (ER and SE) does not affect the risk and degree of POS in class I/II and class V restorations. Further research is required to verify whether these findings apply to different forms of composite resin restorations. Besides the fact that TE barely increase postoperative sensitivity, it also yields superior cosmetic results.

Bond Strength of Resin Composite Posts Placed in Primary Teeth: A Comparison of Adhesive Systems

Objective: In this study, researchers used two different adhesives to determine which ones had the strongest push-out connection between resin composite posts and primary teeth's intracanal dentin. Methods: Fifty primary lateral incisors were split into two groups (n = 25) and treated with either Adper Single Bond 2 (ASB group) or Clearfil SE Bond 2 (CSE). Resin composite was used to fill the canal in the root's coronal one-third. A universal testing equipment was used to conduct the push-out evaluation. The data was analyzed using t-test. Results: Strengths of push-out bonds were found to be significantly different amongst the two groups using t-test (p=0.000). The mean±S.D push-out bond strength of the samples in ASB group was 8.41±4.83 Mpa, while mean±S.D push-out bond strength of the samples in CSE group was 14.21±4.03 Mpa. Most failures were adhesive, and there was no difference (p=0.327) in the fracture mode distribution between bonding agents. Conclusion: In terms of push-out bond strength, CSE group was clearly superior to ASB group. When placing resin composite posts in primary anterior teeth, it is advised to utilize a universal adhesive system and self-etch adhesives from the sixth generation. Due to their simplicity of use, reduced technical sensitivity, and reduced number of required clinical processes, bonding agents may be a desirable choice for repairing primary teeth with short resin composite posts. Keywords: Adhesive system, bond strength, primary teeth, resin composite

Laboratory study and clinical application of adhesive marginal fit of dental hard tissue restorations

BACKGROUND: Dental caries is the most common disease of the oral cavity, which can usually be treated by direct composite restoration.&#x0D; AIM: To assess the quality of the marginal fit of adhesive systems and photocomposites to the hard tissues of the tooth.&#x0D; MATERIALS AND METHODS: A scanning electron microscopic study was conducted with 30 restorations on teeth previously removed for medical reasons using a 7th-generation adhesive system from the universal group of various manufacturers and composite materials. The experiment included Tetric N-Bond Universal (Ivoclar Vivadent), PrimeBond Universal (Dentsply Sirona), OptiBond Universal (Kerr), and composite materials (OptiShade, сeram.х SphereTec, and Tetric N-Ceram). All of these adhesives can be used with any enamel and dentin conditioning technique or with dual-curing composites; thus, their use is relevant in orthopedic dentistry. Teeth sections were made with restorations and scanning electron microscopy was performed.&#x0D; RESULTS: The self-etching adhesives of the universal group produced different results after studying the electron diffraction patterns of the teeth sections with restorations. The OptiBond Universal (Kerr) adhesive system had the best marginal fit, followed by Tetric N-Bond Universal (Ivoclar Vivadent) and Prime Bond Universal (Dentsply Sirona). A clinical case of restoration with a combination of class 5 and 3 cavities according to Black was represented by the OptiShade material.&#x0D; CONCLUSION: A violation of the marginal fit of the material in the zone of contact with the hard tissues of the tooth was noted in 60% of the cases when using the composite material Ceram.x SphereTec (Dentsply Sirona) and the adhesive PrimeBond Universal; 20% Tetric N-Ceram (Ivoclar Vivadent) and PrimeBond Universal adhesive; in 10% composite OptiShade (Kerr) and adhesive OptiBond Universal (Kerr). The adhesive should be applied with a brush.