Adhesion Protocol Research Articles

The effect of post space irrigation protocol and adhesive strategy on push out bond strength to radicular dentin: A network meta-analysis

Introduction: Establishing an effective bond with root dentin remains a complex task, with bond strength diminishing from the coronal to the apical third as a result of reduced dentinal tubule density and limited access to light curing instruments. This network meta-analysis studied the effect of cement and irrigation protocols on push out bond strength to radicular dentin. Methods: In vitro studies evaluating self- etch, self-adhesive, total etch resin cements, and ethylenediaminetetraacetic acid (EDTA), sodium hypochlorite (NaOCl), distilled water, chlorhexidine (CHX) irrigants were included. A network meta-analysis was performed using a random effect model. The efficacy of the different irrigation and adhesion protocols was ranked using P scores. A comprehensive search was carried out in the "Web of Science", "PubMed", "Scopus", and "Embase" databases by October, 2022. Results: It was shown that the irrigation protocol and adhesive strategy with the greatest chance of producing higher bond strength was EDTA+NaOCL/Total etch (push out MD 6.69 MPa, P=0.95) proceeded with CHX/self -adhesive (push out MD 3.70 MPa, P=0.77) compared to Distilled water/Total etch as the control group. Conclusion: Network meta-analyses identified EDTA+NaOCL/Total etch resin cement and self-adhesive cements/CHX as the most efficient protocols for increasing push out bond strength to radicular dentin.

The Losing Battle Against Neoliberal Trade Agreements in Latin America: Social Resistance Against the MTA Between Ecuador, Peru, and the European Union

AbstractThis article studies the influence of the antineoliberal social movements in Peru and Ecuador in the face of the Multiparty Trade Agreement (MTA) between both countries and the European Union (EU). To identify and analyze this influence, a transdisciplinary theoretical framework was created, integrating debates and concepts from social movement theory and critical international political economy. In Peru, the movement used European allies to establish their demands on the EU’s agenda, which resulted in increased pressure on the government to enforce labor rights and environmental standards. In Ecuador, the movement was able to establish food sovereignty and the rejection of free trade in the national constitution. As a result, the negotiations with the EU were delayed and Ecuador achieved certain exceptions in its adhesion protocol. Nevertheless, both movements were unable to maintain their influence, due to political and socioeconomic dynamics on the domestic and global levels.

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.

Endocrown Restorations: A Conservative Approach to Restore Extensively Damaged Endodontically Treated Teeth

Rehabilitation of endodontically treated molar still remains a controversial issue. Over the years, the use of post-retained restorations has been questioned because of potential tooth weakening. Nowadays, endocrowns are considered as a reliable alternative technique to restore endodontically treated teeth with extensive coronal damage. This partial restoration requires specific preparation design and rigorous adhesion protocol. The present paper aimed to describe the preparation technique for endocrowns, indications, contraindications, and best material adapted for fabrication. This was illustrated through a clinical case to restore the first right mandibular molar by an endocrown fabricated from lithium disilicate-ceramic (IPS e-max CAD).

Effect of Different Surface Treatments on the Long-Term Repair Bond Strength of Aged Methacrylate-Based Resin Composite Restorations: A Systematic Review and Network Meta-analysis.

This systematic review and network meta-analysis is aimed at investigating the effect of common surface treatments on the long-term repair bond strength of aged resin composite restorations and to rank and compare these surface treatments. In vitro studies evaluating the methacrylate-based resin composites subjected to rigorous aging protocols before and after being repaired with a new composite were included. A frequentist network meta-analysis was carried out using a random effects model. P scores were used to rank the efficacy of the surface treatments. Also, the global and node-split inconsistencies were evaluated. Web of Science, PubMed/Medline, Scopus, and Embase databases were searched until July 07, 2022. Twenty-six studies were included in the meta-analysis. The results showed that the application of silane and a total-etch (shear MD 32.35 MPa, 95% CI: 18.25 to 46.40, P score 0.95; tensile MD 33.25 MPa, 95% CI: 25.07 to 41.44; P score 0.77) or a self-etch (shear MD 38.87 MPa, 95% CI: 21.60 to 56.14, P score 0.99; tensile MD 32.52 MPa, 95% CI: 23.74 to 41.29; P score 0.73) adhesion protocol subsequent to the roughening with diamond bur produced the highest (micro)tensile and (micro)shear bond strengths compared to diamond bur alone as the control group. There was no difference between self- and total-etch adhesive protocols. Mechanical surface treatments yielded greater bond strength when used alongside the chemical adhesive agents. Further, it is possible to achieve acceptable repair bond strength using common dental clinic equipment. Therefore, clinicians could consider repairing old resin composites rather than replacing them.

Microbial Protocols for Spacecraft: 1. Effects of Surface Texture, Low Pressure, and UV Irradiation on Recovery of Microorganisms from Surfaces.

Modeling risks for the forward contamination of planetary surfaces from endemic bioburdens on landed spacecraft requires precise data on the biocidal effects of space factors on microbial survival. Numerous studies have been published over the preceding 60 years on the survival of diverse microorganisms exposed to solar heating, solar ultraviolet (UV) irradiation, vacuum, ionizing radiation, desiccation, and many other planetary surface conditions. These data were generated with diverse protocols that can impair the interpretations of the results due to dynamic experimental errors inherent in all lab protocols. The current study (1) presents data on how metal surfaces can affect spore adhesion, (2) proposes doping and extraction protocols that can achieve very high recovery rates (close to 100%) from aluminum coupons with four Bacillus spp., (3) establishes a timeline in which dried spores on aluminum coupons should be used to minimize aging effects of spore monolayers, (4) confirms that vacuum alone does not dislodge spores dried on aluminum coupons, and (5) establishes that multiple UV irradiation sources yield similar results if properly cross-calibrated. The protocols are given to advance discussions in the planetary protection community on how to standardize lab protocols to align results from diverse labs into a coherent interpretation of how space conditions will degrade microbial survival over time.

Effect of antimicrobial photodynamic therapy with different photosensitizers and adhesion protocol on the bond strength of resin composite to sound dentin.

The aim of this study is to evaluate the influence of the antimicrobial photodynamic therapy with phycocyanin and toluidine blue on the bond strength of resin composite to the sound dentin. The samples include 120 tooth blocks taken from 60 human extracted sound third molar teeth. They were randomly divided into 12 groups and disinfected with two different photosensitizers (Phycocyanin and Toluidine blue) activated by 635 nm diode laser for aPDT procedure. Then two different protocols (total-etch and self-etch) of universal adhesive system (G-Premio BOND, GC Dental Products CORP. Japan) were applied. The samples then filled with resin composite (Gradia® Direct, GC Dental Products CORP. Japan). After 10000 cycles of thermocycling, all samples were subjected to the micro shear bond strength (μSBS) test using a universal testing machine (1 mm/min). The data were analyzed with One Way ANOVA. The effect of aPDT using both photosensitizers (phycocyanin and toluidine blue O) on the bonding strength to dentin was not significant (P>0.05). However, the bonding strength of total etch groups was reduced significantly (P<0.05) after aPDT using both photosensitizers. Phycocyanin self-etch group showed the greatest bonding strength (19.48 ± 3.89 MPa) in comparison to other aPDT groups. No significant reduction after thermocycling in dentin bond strength was observed in all groups (P>0.05), with exception of control total etch groups, which showed significant difference (P<0.05). aPDT using toluidine blue O and phycocyanin has no adverse effect on bonding to sound dentin when using universal adhesive in self-etch protocol. Phycocyanin is more recommended to be used in aPDT in comparison to toluidine blue as a natural photosensitizer.

Bond strength of self-adhesive resin cement to dentin using different adhesion protocols.

BackgroundThe treatment of dentin before the use of self-adhesive cements is still a crucial point to achieve the best bond strength values. The objective of this study was to evaluate the bond strength between dentin and composite resin using different adhesion strategies with self-adhesive resin cement. Material and MethodsForty healthy third human molars were randomly divided into 4 groups (n = 10): CA (control); application of self-adhesive cement (Rely X U200, 3M ESPE), AD + CA: only application of conventional adhesive (Adper Single Bond 2, 3M ESPE) + self-adhesive cement, AC + AD + CA; conditioning with 37% phosphoric acid for 15 seconds + application of conventional adhesive + self-adhesive cement and AC + CA; conditioning with 37% phosphoric acid for 15s + self-adhesive cement. Blocks made of composite resin (Z250 XT, 3M ESPE) were cemented over dentin. The samples were stored for 24h in distilled water at 37ºC and then were sectioned on a metallographic cutter to obtain tooth picks with approximately 1.0 mm2 in cross section. A universal testing machine was used with a speed of 0.5 mm/min to test the microtensile bond strength,. The fracture patterns were classified as adhesive, cohesive and mixed failures. The data (MPa) were analyzed statistically by One-way ANOVA and Holm-Sidak test (α=5%). ResultsThe AC + AD + CA and AC + CA groups had the highest averages, while the CA and AD + CA groups had the lowest bond strength values. Adhesive failure was prevalent in all groups. ConclusionsConditioning with 37% phosphoric acid for 15s increases the adhesion of the self-adhesive resin cement to the dentin, regardless of the use of dental adhesive system. Key words:Resin cement, microtensile bond strength, acid conditioning.

Assessment of the Shear Bond Strength of Composite Resin to Fresh Amalgam Using Different Adhesion Protocols: An In Vitro Study

Introduction: This study was conducted to evaluate and compare the effect of using three adhesive systems on the shear bond strength between composite resin and fresh amalgam. Materials and Methods: Amalgam samples were assigned into three groups according to the adhesive systems being used prior to the composite resin application. Group A (n = 10): universal self-etch bonding system (Single Bond Universal Adhesive, 3M, Neuss, Germany) was applied and light cured. Group B (n = 10): universal self-etch bonding was applied and light cured, followed by a thin layer of nanohybrid flowable composite (Tetric N-Flow, Ivoclar Vivadent, Liechtenstein), then light cured. Group C (n = 10): self-adhesive dual-cure luting resin cement (Calibra Universal, Dentsply Sirona, Charlotte, NC) was applied in equal quantity for each sample over amalgam surface. Composite resin was then applied by plastic instrument in a single increment to the height of the hole (2 mm), then celluloid strip was placed and light cured. After thermocycling, a shear bond test was performed. Results: Resin luting cement interface showed the higher significant bond strength, followed by universal bonding agent − flowable composite interface. The universal bonding interface group yielded the lowest results. Conclusion: The application of self-adhesive dual-cure luting resin cement resulted in significant increase in bond strength between composite resin and fresh amalgam.

Reparo em resina composta usando adesivo universal melhora a estabilidade da união

Repair in resin-based composite is a procedure that has shown good results, when properly indicated. In cases of fracture or stainning, the total removal of the restoration can cause unnecessary wear on the dental element. This study evaluated the aging effect on the bond strength of a universal adhesive containing silane, and/or application of silane separately for composite repairs. Resin composite blocks were thermocycled and divided according to adhesion protocol (n=10): silane(Sil), conventional adhesive(CA), universal adhesive(UA), Sil+CA(SilCA), and Sil+UA(SilUA). Layers of resin composite were added and blocks were sectioned and divided into 2 subgroups: 24h and 4 months of water storage. Microtensile bond strength test was performed and data were statistically analyzed (a = 0.05). After 4months of aging SilCA and SilUA showed a significant bond strength reduction, while for UA the bonding remained stable.

Comparative Evaluation of the Microtensile Bond strength of composite resin to Bleached Enamel: An In vitro Experimental Study

Aim: Comparative evaluation of the effectiveness of 10% sodium ascorbate solution and delayed treatment on the microtensile bond strength of nanocomposite to bleached enamel using two step etch and rinse and self-etch adhesive technique. Materials and methods: Forty extracted human maxillary central incisors were decoronated, and the crown portion was embedded in acrylic resin with the buccal surface facing upwards. The specimens were randomly allocated to four groups which were further sub-divided into two groups according to the adhesion protocol. Group I- (control group): No bleaching followed by restoration. Group II: Bleaching followed by immediate restoration. Group III: Bleaching followed by surface treatment with 10 % sodium ascorbate for 30 mins followed by restoration. Group IV: Bleaching followed by restoration after 14 days. Result: Statistically significant differences were found between microtensile bond strength of bleached enamel with surface treatment with 10% sodium ascorbate solution and no surface treatment group. Conclusion: Bleaching followed by surface treatment with 10 % sodium ascorbate for 30 mins followed by restoration showed similar strength as compared the control group.

Evaluation of Adhesion Protocol for Titanium Base Abutments to Different Ceramic and Hybrid Materials.

Scientific evidence regarding conditioning of different ceramic and hybrid materials and their bonding on titanium abutments is lacking. Titanium disks (Tritan) (N=450, n=15) were randomly cemented onto five different ceramic and hybrid materials, namely 1. Zenostar T, 2. Lava Ultimate, 3. IPS e.max CAD, 4. Vita Enamic multicolor and 5. G-ceram using three different cements, Panavia 21, TheraCem and Multilink hybrid abutment. Half of all specimens were thermocycled (5000 cycles, 5-55°C), while the other half were kept dry. Macro shear bond testing was conducted using a universal testing machine. Failure types were classified using a digital microscope. Data was statistically analyzed with three-way ANOVA and Tukey HSD post hoc tests. Both the ceramic (P⟨0.0001) and cement type(P⟨0.0001) significantly affected the shear bond strength(MPa), while thermocycling did not (P⟩0.05). The incidence of cohesive (50.34%) and adhesive failures (49.66%) were not significantly different. As for implant superstructures, when ceramics are bonded to titanium bases, the ceramic and cement type both have an impact on the bond strengths along with the conditioning and bonding protocols for each substrate. An equal affinity of the cements tested to the ceramic, hybrid materials and to titanium can be assumed. Combination of zirconia and TheraCem can be recommended for clinical use.

Microtensile Bond Strength of Etch-and-Rinse Adhesives in Different Hydroabrasion Conditionings.

The aim of the present study was to in vitro evaluate the effect of dentin conditioning with hydroabrasion on the microtensile bond strengths of three adhesive systems, compared to the standard etch-and-rinse technique. Sixty extracted human third molars were collected, and their midcoronal occlusal dentin was used for the microtensile bond strength test. Teeth were randomly assigned to three groups according to the adhesive system used: ExciTE F DSC, ENA Bond, and Scotchbond Universal. Specimens from each group were further divided into four subgroups: control specimens were treated with standard adhesive procedures; hydroabraded (HA) specimens were subjected to preventive hydroabrasion with three different intensity levels. After bonding procedures, composite crowns were incrementally built up. After thermocycling, specimens were subsequently sectioned into 1 × 1 mm sticks, and microtensile bond strengths were measured. Data were statistically analyzed. Failure mode analysis was performed. There were no significant differences in terms of bond strength between standard adhesion protocols and adhesion with HA preconditionings. On the other hand, the type of adhesive used had a significant effect on the tensile bond strength. Subgroups treated with hydroabrasion at higher intensity showed a slightly increased frequency of cohesive fractures. In conclusion, hydroabrasion can be used for dentin cavity preparation or finishing, since it does not seem to affect the bonding effectiveness.

Effect of Different Adhesion Protocols on the Shear Bond Strength of Universal Adhesive Systems to Sound and Artificial Caries-Affected Dentin

AbstractObjective Bonding to different dentin substrates influences resin composite restoration outcomes. This study investigated the influence of different adhesion protocols on the shear bond strength of universal adhesive systems to sound and artificial caries-affected dentin (CAD).Materials and Methods Occlusal enamel of 80 premolars were wet grinded to obtain flat midcoronal dentin. Specimens were equally divided according to the substrate condition: sound and CAD by subjecting to pH-cycling for 14 days. Each dentin substrate was bonded with the adhesive systems used in this study: Single Bond universal adhesive or Prime&amp;Bond universal (applied either in etch-and-rinse or self-etch adhesion protocol). Adhesive systems were utilized according to manufacturers’ instructions, then resin composite was built up. Specimens were tested for shear bond strength. The data were analyzed by three-way analysis of variance, and failure modes were determined using stereomicroscope.Results There was no statistically significant difference between the two tested adhesive systems on artificially created CAD with different adhesion protocols. On sound dentin, Single Bond universal, either in the etch-and-rinse or self-etch adhesion protocols, revealed higher statistically significant shear bond strength mean values compared with CAD.Conclusion Single Bond universal adhesive in an etch-and-rinse adhesion protocol improved only bonding to sound dentin, while no added positive effect for the etching step with Prime&amp;Bond universal adhesive was found when bonded to both sound and CAD substrates. The influence of CAD on the performance of the universal adhesives was material-dependent.

Effect of enamel regions and prisms orientation on the microshear bond strength of a multimode and a two-step self-etch adhesives applied with different adhesion protocols

Multi-mode adhesives (MMA) with different adhesion protocols are postulated to improve bonding to enamel. Thus, this study compared the microshear bond strength (μSBS) of (MMA) and self-etch adhesive (SEA) to different regions and prism orientations of enamel. Materials and methodsThirty premolars were assigned for preparing 160 specimens for μSBS. Specimens were equally divided (n = 80) according to the enamel region evaluated: cuspal, and mid coronal enamel. Each group was divided into two subgroups according to the direction of tooth sectioning: axial, or tangential. Each subgroup was divided into two classes according to the applied adhesive system; either MMA or SEA. Finally; each class was divided into two subclasses (n = 10) according to the adhesion protocol utilized; self-etch adhesion protocol or with etch-and-rinse (pre-etching) adhesion protocol. Nano-filled flowable composite was used to prepare μSBS specimens. μSBS was measured using universal testing machine at a cross head speed of 0.5 mm/min until failure. Statistical analysis was carried out using four-way ANOVA test. ResultsDifferent enamel regions had no statistically significant effect at P-value 0.491. Direction of sectioning had a statistically significant effect at P-value <0.001. Adhesive systems had a statistically significant effect at P-value <0.001. Adhesion protocols had a statistically significant effect at P-value 0.001. ConclusionPre-etching of enamel before the application of the MMA improves the resin-enamel μSBS, while there was no advantage of the pre-etching step with the SEA. The μSBS of the tested adhesive systems were influenced by the direction of enamel prisms. The μSBS of the tested adhesive systems were not influenced by the enamel regions tested.

An in vitro evaluation of microleakage of resin based composites bonded to chlorhexidine-pretreated dentin by different protocols of a universal adhesive system

PurposeThis study compared microleakage of different resin based composite (RBC) materials bonded to dentin, after chlorhexidine (CHX) application, by different adhesion protocols of a universal adhesive system. MethodsClass V cavities were prepared on the buccal and lingual surfaces of 40 premolar teeth. The “etch-and-rinse” technique of a universal bond adhesive system (Single Bond Universal Adhesive) was used on buccal preparations, while the “self-etch” protocol was used on the lingual surfaces. Two RBCs, one bulk fill (Filtek Bulk Fill [FBF]) and one conventional (Filtek Z350 XT [Z350XT]), were used. Teeth were divided into two groups of 20 teeth each, 10 per each RBC (n = 10): (1) control; and (2) pretreatment with 2% CHX. For FBF groups, teeth were restored with a single increment; however, for Z350XT, a layering technique was used. Teeth were aged by thermo-cycling and prepared for microleakage testing. Dye penetration was evaluated and scored from 0 to 4. Data were analyzed at a significance level of P < 0.05. ResultsThe highest microleakage mean scores were found in the control group of the etched margins for both RBCs (2.80 ± 1.033 FBF and 2.10 ± 1.370 Z350XT). The CHX-pretreated group showed significantly lower microleakage than the control for FBF only (P = 0.008). No significant difference was found between groups for the “self-etch” protocol (χ2 = 0.884, P = 0.08). No significant differences were found between FBF and Z350XT in all study groups (P > 0.2). ConclusionsWhen the “self-etch” protocol of the universal adhesive system was used, dentin microleakage was not affected by CHX-pretreatment when teeth were restored with bulk fill or conventional RBCs. In the “etch-and-rinse” protocol, CHX application improved the marginal seal before restoration with bulk fill material. However, in the absence of CHX, the “etch-and-rinse” protocol negatively affected marginal integrity.

Shear Bond Strength of Bulk-Fill Composites to Resin-Modified Glass Ionomer Evaluated by Different Adhesion Protocols.

ObjectiveThe aim of this study was to investigate the shear bond strengths (SBS) of different nano-resin-based composites (RBCs) to resin-modified glass-ionomer cement (RMGIC) after the application of different adhesion protocols.Material and MethodsThree RBCs (Filtek One Bulk Fill [FOBF], Tetric N-Ceram Bulk Fill [TNCBF], and Filtek Z350 XT [Z350XT]) were used as layering materials over GC Fuji II LC RMGIC. Three adhesive systems — Total-etch (OptiBond Solo Plus [OB]), self-etch (CLEAR FIL SE Bond 2 [CFSE]), and a universal bond (Single Bond Universal [SBU]) — were used. In total, 160 RMGIC blocks were prepared. Ten samples (n = 10) were layered with the same material to form a reference-cohesive control group. The remaining samples were distributed among the following groups: No treatment [NT]; Total-etch [OB]; Self-etch [CFSE]; Universal bond in the “total-etch” mode [SBU-TE]; and Universal bond in the “self-etch” mode [SBU-SE]. Samples were stored, and aged by thermocycling (5000 cycles at 5 °C / 55 °C, 30 s) and then prepared for SBS testing. Fracture modes were examined by stereomicroscopy. Data were collected and analyzed statistically at a significance level of P<0.05.ResultsThe highest mean SBS (14.30±1.08 MPa) was reported in the OB group with the TNCBF material, while the lowest was in the NT group (5.05±0.69 MPa) with FOBF. Samples in the NT group showed SBS statistically significantly lower than those of samples in all other groups (P<0.0001). Bulk-fill materials had significantly higher SBS than Z350XT in OB, CFSE, and SBU-SE (P<0.0001). SBU-TE produced SBS statistically significantly lower than those of other groups for FOBF (P<0.0001), and lower than that of OB for TNCBF (P=0.027).ConclusionOB, CFSE, and SBU-SE are reliable adhesion protocols for bonding bulk-fill RBCs to RMGIC when the “sandwich technique” is used for restorations. However, SBU-TE may not be effective in such procedures.

Scanning electron microscopy approach to observe bacterial adhesion to dental surfaces

AIMTo describe the in vitro bacterial adhesion protocol of Streptococcus mutans and Lactobacillus casei on dental surfaces for a qualitative approach by Scanning Electron Microscopy (SEM) observations. A control and Amelogenesis Imperfecta (AI) affected teeth were used to validate the protocol. METHOD DETAILSEight teeth were collected and fixed in 10% formalin during 10 days. Crowns were fragmented into 4 parts and kept in the freshly prepared artificial saliva. For the preparation of bacterial suspensions, bacterial strains (S. mutans and L. casei) were incubated in a freshly prepared culture medium. After two successive cultures at 37 °C and 3 rinces, bacterial suspensions were prepared in artificial saliva and adjusted to correspond to 108 CFU ml−1. Bacterial adhesion was carried out by sedimentation. Dental fragments were immersed in bacterial suspensions and rinsed with PBS to remove non adherent bacteria. Adherent bacteria were fixed with glutaraldehyde. Finally, teeth samples were dehydrated, coated, dried and observed using high-resolution SEM (JEOL, JSM-5400). RESULTSSEM observations showed adherence of spheric stuctures, identified as S. mutans and bacilic structures identified as L. casei. CONCLUSIONAdhesion of bacteria could be observed by SEM and depends on the quality of dental mineralized tissues.

Cell-Based Adhesion Assays for Isolation of Snake Venom's Integrin Antagonists.

Snake venoms could lead to the development of new drugs to treat a range of life-threatening conditions like cardiovascular diseases. Most snake venoms contain a large variety of lethal toxins as well as anti-adhesive proteins such as disintegrins, which have evolved from the harmless compounds ADAMs (proteins with a disintegrin and a metalloprotease domain) and C-type lectin proteins which disturb connective tissue and cell-matrix interaction. These anti-adhesive proteins target and block integrin receptors and disrupt normal biological processes in snakes' prey such as connective tissue physiology and blood clotting. This chapter provides the experimental details of a practical, cell-based adhesion protocol to help identify and isolate disintegrins and C-type lectin proteins from snake venoms, important tools in integrin research and lead compounds for drug discovery.

Effect of different adhesive protocols on bond strength between composite resins for indirect use and repair materials

The aim of this work is to evaluate the effect of different adhesive protocols on the bond strength (SBS) of composite resin for indirect use to repairs of bulk-fill or conventional nanoparticulated composites. Forty-eight cylindrical specimens of composite resin for indirect use were prepared, aged, and randomly divided into four groups (n = 12), a control group without any adhesion protocol, and three experimental groups: Silane + Scotch Bond Multipurpose adhesive (S + SBMP), Tetric N Bond Universal (TBU), and Single Bond Universal (SBU). The treated surfaces were restored using two different composite resins: Filtek Bulk-Fill or Filtek Z350XT. Then, the specimens were submitted to the SBS test, and the resultant data were analyzed with ANOVA on ranks test and Tukey’s test (α = 0.05). There were no significant differences between the two types of resins used as repair material. For both resins, the groups treated with S + SBMP obtained the highest values (p < 0.001). Groups TBU and SBU did not have statistically significant differences between them. Pre-treatment with a silane coupling agent and a layer of a hydrophobic adhesive can improve the bond strength of repairs performed on a composite resin for indirect use.