Caries-affected dentin disinfection using Triphala, Indocyanine green, and Potassium Titanyl Phosphate laser and their effect on adhesive bond strength

Canal disinfectants: Potassium titanyl phosphate laser, magnesium oxide nanoparticles, and aloe-emodin PDT on smear layer removal and bond strength of glass fiber post to root dentin

AIM

To assess the influence of different root canal disinfectants i.e., Potassium titanyl phosphate laser (KTPL), Aloe-emodin (AE) mediated Photodynamic therapy (PDT), Magnesium oxide (MgO) nanoparticles (NPs) on smear layer (SL) removal and push out bond strength (PBS) of Glass fiber post (GFP) to the canal dentin.

MATERIAL AND METHOD

Forty-eight extracted premolars, having a single root and a solitary canal were included. A root canal procedure was performed on each tooth and subsequently, post-space preparation was executed using peeso-reamers leaving approximately 4 mm of gutta percha in the canal. According to the type of disinfection used the samples were categorized into 4 groups (n = 11). Group 1 (2.5 % NaOCl + EDTA), Group 2 (KTPL+ EDTA), Group 3 (AE mediated PDT+ EDTA), and Group 4 (MgONPs+ EDTA). Cementation of fiber posts was performed using a self-adhesive resin cement. Scanning electron microscope (SEM) assessed the SL removal from the canals (n = 2). Failure mode and PBS were assessed with a stereomicroscope and universal testing machine respectively(n = 10). One-way analysis of variance and Tukey posthoc test at p-value  ≤ 0.05 were used to compare the mean scores of PBS and SL removal.

RESULT

The cervical region in Group 4 (MgONPs + EDTA) samples showed the highest PBS scores (10.41±0.38 MPa) and the maximum level of SL removal (1.55±0.10). Conversely, Group 3 at the apical third of the root (AE mediated PDT +EDTA) displayed the least efficacy for SL removal (2.81±0.09) and lowest PBS(7.69±0.19 MPa).

CONCLUSION

MgO nanoparticles, when paired with Ethylenediaminetetraacetic acid as a final irrigant, offer a promising alternative to conventional root canal sterilants.

To investigate the impact of different post-space disinfectants Nd: YAP laser, Radachlorin, and Calcium Oxide Nanoparticles on Smear layer removal efficacy and bond durability of PEEK posts to canal dentin

AIMS

Effect of post-space disinfectants Nd: YAP laser, Radachlorin® photosensitizer, and calcium oxide nanoparticles (CaONPs) on the smear layer (SL) removal efficacy and push out bond strength (PBS) of polyetheretherketone (PEEK) post to root dentin.

METHODOLOGY

Forty-four human premolars possessing a single root having a complete apex were acquired and endodontically treated. Gates glidden drills were used to prepare the post space. The teeth were then randomly allocated into 4 groups according to the disinfectant used (n=11) Group 1: 2.5% NaOCl+17% EDTA, Group 2: Nd: YAP laser+17% EDTA, Group 3: Radachlorin+17% EDTA and Group 4: CaONPs+17% EDTA. A single sample from each respective group was carefully sectioned and observed under SEM magnification for SL removal(n=1). PEEK post was cemented using resin cement followed by artificial aging (n=10). PBS testing was conducted using a universal testing machine and failure mode was analyzed under a stereomicroscope. A one-way analysis of variance, accompanied by post hoc analysis was applied for statistical assessment of data (p<0.05) RESULTS: The specimens from Group 1 (2.5% NaOCl+EDTA) (1.65±0.02) showed the highest efficacy in eliminating SL from the canal as well as the highest PBS. Conversely, Group 3 (Radachlorin+ EDTA) samples revealed the least efficacy in the removal of SL and bond integrity of PEEK post.

CONCLUSION

Sodium hypochlorite followed by ethylenediamine-tetra acetic acid displayed better performance than all the other tested groups in SL removal and bond integrity outcomes when PEEK post was bonded to the canal dentin.

Aloe-Emodin activated by Photodynamic therapy and diode laser on carious affected dentin and survival of S. mutans. An-invitro SEM assessment

AIMS

To evaluate the effect of different sterilizing agents i.e., Chlorhexidine (CHX), Diode laser (DL) and Aloe-emodin (AE) activated via Photodynamic therapy (PDT) on the viability of Streptococcus mutans (S. mutans) and the shear bond strength (SBS) of self-etch (SE) adhesive to carious affected dentin (CAD) MATERIAL AND METHODS: Forty-four human molars in which carious lesion extends up to the middle third of the dentin ICDAS criteria- 5 were collected and disinfected using 0.5% chloramine Tsolution. To identify the CAD, visual and tactile examinations were used. Specimens were randomly assigned into four experimental cohorts based on cavity disinfection protocol (n=11) Group 1 (No disinfection), Group 2 (CHX), Group 3 (DL), and Group 4 (AE-mediated PDT). Fresh cultures of S.mutans were cultivated on CAD and their survival rate assessment was performed following the type of disinfection. SE adhesive and composite application were performed on CAD following assessment of SBS and failure mode utilizing a universal testing machine (UTM) and stereo microscope respectively. Quantification of resin tags was performed via Scanning electron Microscopy (SEM). One-way ANOVA and Tukey post hoc test were implemented to investigate the statistical variances among different experimental groups (p≤0.05) RESULTS: The lowest survival rate was presented in Group 4 (AE mediated PDT) (1.52±1.32CFU/mL) samples. Whereas, the highest survival was established in control (3.27±0.82 CFU /mL). Group 3 (DL) treated CAD presented the lowest bond strength (7.12±0.03MPa) and shortest resin tag length (53.79±2.32μ m). Whereas, the highest SBS (9.45±0.14MP) and longest resin tags (109.21 ± 1.09μ m) were exhibited by Group 4 (AE-mediated PDT) CONCLUSION: Aloe-Emodin mediated photodynamic therapy could serve as a potent approach for CAD disinfection as it exhibits exceptional antibacterial efficiency and also enhances the bond strength of the self-etch adhesive to carious affected dentin.

The Adhesive Strength and Degree of Conversion of Remineralizing Hydroxyapatite, Amorphous Calcium Phosphate, and Cerium Oxide Fillers in Experimental Adhesive: A SEM and EDX Analysis

Remineralizing fillers Amorphous-calcium-phosphate nanoparticles (ACP-NPs), hydroxyapatite (HA-NPs), and cerium dioxide (CeO2-NPs) on the micro-tensile bond strength (μTBS) and degree of conversion (DC) of the experimental adhesive (EA) to caries-affected dentin (CAD). Forty molars with carious lesions on the occlusal surface extending to the middle third of the dentin were included. The characterization of ACP-NPs, HA-NPs, and CeO2-NPs was performed using SEM and EDX. CAD samples were arbitrarily assigned to four groups based on the application of remineralizing fillers infused into EA. Group 1, Unmodified EA; Group 2, 5% ACP-NPs in EA; Group 3, 5% HA-NPs in EA; and Group 4, 5% CeO2-NPs in EA. The composite buildup on the CAD surface was followed by artificial aging. μTBS measurements were evaluated using UTM. The DC of the modified EA was assessed using FTIR spectroscopy. One-way ANOVA and Tukey post hoc tests were used to analyze μTBS and DC. CeO2-NPs + EA displayed the highest bond integrity scores. The unmodified EA samples exhibited the lowest μTBS values. ACP-NPs + EA and the unmodified adhesive demonstrated comparable bond strength (p > 0.05). DC of samples in Group 2: ACP-NPs + EA (66.11 ± 6.33) was comparable to Group 1 HA-NPs (73.51 ± 4.37) (p > 0.05). The highest DC was observed in Group 1 (Unmodified EA). CeO2-NPs have the potential to improve bond strength scores when used as a remineralizing filler in EA adhesives. However, the incorporation of NPs at 5% in adhesive reduced the DC.

Effects of Er,Cr:YSGG Laser Disinfection on the Bond Strength of Bioactive-Restorative Materials to Caries-Affected Dentin

Objective: This study aimed to evaluate the effects of different Er,Cr:YSGG laser disinfection protocols on the bonding performance of bioactive restorative materials to caries-affected dentin (CAD). Background: With the adoption of minimally invasive caries removal techniques, bonding to CAD has become increasingly important. Adhesion challenges caused by CAD can be overcome through the application of effective disinfection methods and the selection of compatible bioactive restorative materials. Methods: A total of 120 human third molars (240 specimens) were prepared, with dentin surfaces exposed under water cooling. After pH-cycling to simulate CAD, specimens were assigned to four disinfection groups: no disinfection (C), 2% chlorhexidine gluconate (CHX), Er,Cr:YSGG laser at 0.5 W (L1), and 1 W (L2). Four restorative materials (n = 12 per group)-G-ænial Achord (a resin composite used as the control group), Equia Forte HT, Beautifil-II Restorative, and Cention Forte-were applied according to manufacturers' instructions. Shear bond strength (SBS) testing was conducted on 192 specimens, while energy-dispersive spectroscopy (EDS) analyzed F, P, and Ca on 48 specimens, and scanning electron microscopy images were obtained from representative specimens. Results: CHX disinfection significantly improved SBS compared to the control group. Among restorative materials, G-ænial Achord showed the highest SBS, while Equia Forte HT demonstrated the lowest (p < 0.05). L1 disinfection combined with G-ænial Achord achieved the highest bond strength, whereas its combination with Equia Forte HT resulted in the lowest (p < 0.05). EDS revealed increased fluoride content on CAD surfaces treated with CHX. Conclusion: Er,Cr:YSGG laser disinfection at 0.5W improved bonding performance for resin composites. Selecting a disinfection protocol based on the restorative material is crucial for optimizing adhesion to CAD.

Influence of Caries Eradication Techniques via Papacarie, and Er: YAG Laser With Different Adhesive Types Bonded to Composite Restoration in Primary Dentin. An SEM, μTBS, and Microleakage Assessment

Influence of different caries removal techniques using Papacarie and Erbium/yttrium-aluminum-garnet (Er: YAG) laser to different adhesives etch and rinse (ER) and self-etch (SE) restored via tooth-colored material on micro tensile bond strength (μTBS) and marginal leakage scores. Ninety-six extracted primary molars exhibiting moderate caries were allocated into three groups based on the caries removal technique. Group 1: Conventional bur, Group 2: Papacarie gel, and Group 3: Er: YAG laser. After caries removal, specimens from three groups were further allocated into two subgroups based on the type of adhesive used (n = 16). Two-step ER (A) and Two-step SE (B). Composite restoration was built and thermocycling was performed. Microleakage, μTBS, and failure mode were analyzed using a dye penetration test, a Universal testing machine, and a stereomicroscope respectively. Scanning electron microscopy (SEM) evaluation of the composite-CAD interface was performed. One-way ANOVA and the Tukey HSD test were utilized to compare microleakage and μTBS among investigated groups (p < 0.05). The lowest microlekage (13.56 ± 0.02) and highest μTBS (13.26 ± 0.11 MPa) was exhibited by Group 3B (Er: YAG laser-SE). However, the highest microleakage (45.62 ± 0.09) and lowest bond strength (9.34 ± 0.11 MPa) was exhibited by 1A (Conventional bur-ER) treated samples. For caries removal in primary dentition, the Er: YAG laser and Papacarié gel present themselves as appropriate alternatives. These non-invasive methods yield improved mechanical results when utilized with self-etch adhesive system.

Post-Space Disinfectants With Sodium Hypochlorite and Methylene Blue Loaded in Silver and Quartz Nanoparticles Activated by Photodynamic Therapy. A SEM Analysis

Post-space disinfectants methylene blue loaded with silver (Ag) and Quartz nanoparticles (NPs) and MB alone activated by photodynamic therapy (PDT) on the survival of Enterococcus faecalis, smear layer (SL) removal efficacy, and extrusion bond strength (EBS) of fiber posts to canal dentin. Hundred mandibular premolars underwent root canal treatment using the rotary ProTaper system. The canals were obturated and post-space was prepared up to a length of 8 mm, maintaining a 5 mm seal. To assess antibacterial efficacy E. faecalis were inoculated in the canal (n = 20). The samples were then randomly allocated into four groups according to the canal disinfectant used to sterilize the canals. Group 1: 2.5% NaOCl+17% EDTA, Group 2: MB-PDT, Group 3: MB@QP-PDT, and Group 4: MB@AgNP-PDT (n = 25). SEM analysis was conducted on five samples from each disinfectant group to assess the removal of the SL. Survival rates were calculated (n = 5 from each group). Glass fiber post (GFP) was cemented to the root dentin of the remaining samples followed by artificial aging. Sectioning of the specimens was performed in all three-thirds of the canals. PBS was assessed followed by failure evaluation. ANOVA and Tukey post hoc test were used to compare the E. faecalis survival rate and PBS of fiber post among different investigated groups. Group 4 (MB@AgNP-PDT) treated canals exhibited the minimum survival rate (0.30 ± 0.04 CFU/mL) of E. faecalis and maximum PBS. However, the highest survival rate and minimum bond strength of GFP were observed in Group 1 (NaOCl+17% EDTA) and Group 2 (MB-PDT) treated teeth respectively. The highest SL removal was recorded in the coronal section of the samples of Group-4 disinfected with MB@AgNP-PDT. The lowest removal of SL was recorded in Group 2 samples sterilized with MB-PDT at apical one-third. Silver nanoparticles when utilized as nano-carriers to enhance the efficiency of MB activated by PDT, have been shown to exhibit the highest antimicrobial potency, improved capacity for SL removal and improved PBS.

Effect of photodynamic therapy with two photosensitizers on the microtensile bond strength of a universal adhesive to affected dentin

BACKGROUND

This study aimed to evaluate the impact of photodynamic therapy (PDT) using two photosensitizers, methylene blue and indocyanine green, on the microtensile bond strength of a universal adhesive to caries-affected dentin.

METHODS

The occlusal enamel of 60 third molars was cut to expose the inner one-third of the dentin. Artificial caries were induced through a pH cycling process. The samples were divided into three groups: M (Methylene blue+ diode laser), I (Indocyanine green agents+ diode laser irradiation), and control. Each group was further divided into two subgroups according to the adhesive protocol (self-etch, total-etch). After restoring with Gradia composite resin, teeth were sectioned and exposed to 5000 thermal cycles. Microtensile bond strength was measured using a universal testing machine. The data were subjected to two- and one-way ANOVA and paired comparisons were performed by the Tamhane and Tukey tests.

RESULTS

The study found significant effects of the photosensitizer, etching pattern, and their interactions on the microtensile bond strength of composite resin to caries-affected dentin (P < 0.001). In the self-etching mode, PDT with indocyanine green exhibited significantly higher bond strength values compared to PDT with methylene blue (P = 0.001) and the control groups (P < 0.001). However, no significant differences were observed in the total-etch mode. (P = 0.54).

CONCLUSIONS

The etching mode played a more significant role in the bond strength when using the universal adhesive alongside PDT with methylene blue and indocyanine green. Employing two photosensitizers in PDT during the self-etch mode significantly increased the bond strength values.

Modified Hybrid Hydroxyapatite-Silver Nanoparticles Activated via a Blue Light Source in Various Concentrations in Two-Step Self-Etch Adhesive to Caries-Affected Primary Dentin

Aims: To evaluate hydroxyapatite-silver (HA-Ag) hybrid nanoparticles (NPs), as an antibacterial agent when integrated in self-etch (SE) adhesive. Blue light activated HA-Ag hybrid NP incorporation on mechanical properties, degree of conversion (DC), and microtensile bond strength (μTBS). Method: Eighty primary molar teeth have carious lesions reaching the dentin but not involving the pulp. The infected dentin was removed and carious-affected dentin (CAD) was preserved. Forty samples were inoculated with Streptococcus mutans. All primary teeth (n = 80) were allocated into four groups based on the incorporation of HA-Ag hybrid NPs in different concentrations (0%, 1%, 5%, and 10%). Group 1: 0% HA-Ag hybrid NPs + Clearfil SE bond primer, group 2: 1% HA-Ag hybrid NPs + Clearfil SE bond primer, group 3: 5 wt% HA-Ag NPs + Clearfil SE bond primer, and group 4: 10 wt% HA-Ag NPs + Clearfil SE bond primer. The survival rate assessment of S. mutans was conducted on 40 inoculated samples. On the remaining primary teeth (n = 40), Clearfil SE bonding agent was applied uniformly via a blue light source. The composite buildup was performed on the samples and μTBS and failure analysis assessed. Fourier transform infrared spectroscopy was performed to assess DC. Survival rates of S. mutans and μTBS among the tested groups were compared using ANOVA and Tukey post hoc analysis. Results: 10 wt % HA-Ag NPs + Clearfil SE bond primer exhibited the highest level of antibacterial efficacy (0.14 ± 0.02 CFU/mL) against S. mutans. The highest μTBS (18.38 ± 0.78 MPa) at the composite/CAD interface was in group 2 (1 wt % HA-Ag NPs + Clearfil SE bond primer + Clearfil SE bonding agent + activation with a blue light source). The highest DC was observed in the control group with Clearfil SE bond primer + Clearfil SE bonding agent + activation with a blue light source. Conclusion: 1 wt% HA-Ag hybrid NPs showed enhanced antibacterial effectiveness, DC, and bond strength of the SE adhesive to the primary CAD.

Phycocyanin-loaded silver nanoparticles activated with photodynamic therapy and Nd: YAG laser for caries-affected dentin disinfection: Impact on Streptococcus mutans survival rate and shear bond strength to the tooth-colored restorative material

AIMS

To assess the impact of various cavity disinfectants PC-PDT (Phycocyanin activated by Photodynamic therapy), PC@AgNPs-PDT (Phycocyanin and silver nanoparticles activated by PDT), and Nd: YAG laser on the survival rate of S.mutans and the bond integrity of composite restoration METHODS: Sixty human mandibular molars that scored 4 and 5 based on ICDAS criteria were included. The infected dentin was removed while the CAD was preserved based on visual, tactile, and staining assessment. S.mutans were cultured on the CAD of twenty samples. All the specimens were indiscriminately distributed into four groups based on cavity disinfection (n=20 each includes n = 5 each group incubated with S.mutans) Group 1: CHX, Group 2: Nd:YAG laser, Group 3: PC-PDT and Group 4: PC@AgNPs-PDT. S.mutans survival rate was assessed for each group(n = 5). Forty samples underwent composite bonding for SBS and failure mode assessment using universal testing machine (UTM) and stereomicroscope. The calculations for the mean and standard deviation (SD) and their comparison among different groups were performed using a one-way analysis of variance (ANOVA) and the Tukey post hoc test (p ≤ 0.05) RESULTS: CAD surface treated disinfected with PC@AgNPs-PDT yielded the lowest survival rates (0.13 ± 0.05 CFU/ml) and highest SBS (17.23 ± 1.45 MPa). Group 1 (CHX) unveiled the highest survival rate of S.mutans (0.33 ± 0.12 CFU/ml). However, Group 2 (Nd:YAG Laser) (11.87 ± 0.67 MPa) presented the lowest SBS CONCLUSION: The combination of Phycocyanin loaded with silver nanoparticles and activated with Photodynamic therapy demonstrates the highest antimicrobial potential and bond strength of composite restorations.

Remineralizing pretreatment using casein phosphopeptide-amorphous calcium phosphate fluoride, self-assembling peptide, and nanohydroxyapatite gel activation via invisible infrared light on the dentin microhardness and micro shear bond strength to the composite restoration

AIM

Different remineralizing pretreatments Casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF), tricalcium phosphate fluoride (TCP-F), self-assembling peptide (SAP) P11-4 and 10 % Nanohydroxyapatite (nHA) gel activation via invisible infrared light on the dentin microhardness (MH) and micro shear bond strength (µSBS) of composite restoration.

METHODS

Seventy-five human molar teeth were collected and the dentinal surface of all the samples was exposed to different demineralizing solutions. (n = 15) Group 1 (demineralized dentin), Group 2 (CPP ACP), Group 3 (TCP-F), Group 4 (SAP P11-4), Group 5 (nHA gel activation via invisible infrared light). MH assessment was performed using Vickers hardness. Each group of 10 samples was subjected to composite restoration buildup and µSBS were tested. The debonded samples were then observed under a stereo-microscope for failure analysis. ANOVA was conducted, along with Tukey's post hoc analysis, to examine the µSBS of composite and MH of the remineralized surface.

RESULTS

nHA gel activation via invisible infrared light pretreated specimens showed the maximum outcomes of surface hardness (331.2 ± 77.3) and bond strength (10.38 ± 2.77). However, Group 4 (SAP P11-4) (148.3 ± 29.2) remineralized dentin displayed minimum scores of MH and µSBS (5.88 ± 1.01).

CONCLUSION

Remineralizing pretreatment nHA gel activation via invisible infrared light and casein phosphopeptide-amorphous calcium phosphate fluoride seem to improve the dentin MH and µSBS of the composite restoration.

Effect of Casein Phosphopeptide-Amorphous Calcium Phosphate, Proanthocyanidin, Carbon Dioxide Laser Remineralization on the Bond Integrity of Composite Restoration Bonded to Caries-Affected Dentin

Objective: Assessment of different remineralizing pretreatment casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), proanthocyanidin (PA), carbon dioxide laser (CO2), eggshell solution (ES) on the shear bond strength (SBS) of resin composite bonded to remineralized carious-affected dentin (CAD). Materials and methods: Eighty human molars were collected with occlusal caries that extended about halfway into the dentin. Using a water-cooled, low-speed cutting saw, a flat, mid-coronal dentin surface was exposed. CAD was differentiated from healthy dentin. Based on the remineralizing agent used on the CAD surface, the teeth were arbitrarily allocated into five groups (n = 10). Group 1: no remineralizing agent, Group 2: CPP-ACP, Group 3: 6.5% PA solution, Group 4: CO2 laser, and Group 5: ES solution. All samples were bonded to composite and light cured and thermocycled. SBS and failure mode analysis were performed using universal testing and stereomicroscope 40 × . Using SPSS, SBS, and failure mode data were analyzed using analysis of variance and Tukey's honesty significant difference (HSD) test Results: Group 3 (6.5% PA solution; 15.59 ± 1.44 MPa) samples established the maximum bond integrity. Nevertheless, Group 1 (No remineralizing agent; 11.19 ± 1.21 MPa) exhibited the minimum outcome of bond strength. Intergroup comparison analysis showed that Group 1 (No remineralizing agent), Group 2 (CPP-ACP), and Group 4 (CO2 laser) established comparable values of bond strength (p > 0.05). Likewise, Group 3 (6.5% PA solution) and Group 5 (EA solution) also revealed equivalent bond integrity (p > 0.05). Conclusions: PA and ES are considered potential remineralizing agents used for caries-affected dentin surfaces in improving bond integrity to composite resin. However, further studies are advocated to extrapolate the findings of this study.

Adhesive Bond Strength of Restorative Materials to Caries-Affected Dentin Treated with Antimicrobial Photodynamic Therapy: A Systematic Review and Meta-Analysis

Objective: This systematic review aimed to evaluate the adhesive bond strength of restorative materials to caries-affected dentin (CAD) treated with antimicrobial photodynamic therapy (aPDT) in comparison with conventional chemical disinfectants. Methods: Three databases, including the Web of Science, Scopus, and PubMed, were searched to address the focused question: "What is the effect of aPDT compared to conventional chemical disinfection techniques on the adhesive bond strength of restorative materials to CAD?." Search keywords included "dentin*" "adhes bond*" "caries-affected dentin" "photodynamic "photochemotherapy" "photosensitizing agent" "phototherapy" "photoradiation" "laser" "light activated" "photoactivated." A fixed-effects model was used in each meta-analysis and the inverse variance was used to calculate the standard mean difference (SMD). For evaluating the statistical heterogeneity, the Cochrane's Q test and the I2 statistics were used. The risk of bias was evaluated based on the Cochrane Collaboration's tool. Results: Fourteen studies were included in the qualitative as well as quantitative analysis. The results of the meta-analyses exhibited an SMD of 2.38% [95% confidence interval (CI): 2.03-2.73; p < 0.00001], indicating a statistically significant difference in the shear bond strength scores between the tested group (samples treated with aPDT) and the control group (i.e., favoring the sound dentin and/or conventional chemical disinfectants). Contrarily, an SMD of -1.46% (95% CI: -2.04 to -0.88; p < 0.00001) and -0.37% (95% CI: -0.70 to -0.03; p = 0.03) was observed, indicating a statistically significant difference in the microtensile bond strength (μTBS), as well as microleakage scores between the tested group (favoring the samples treated with aPDT) and the control group (i.e., sound dentin and/or conventional chemical disinfectants). Conclusions: Adhesive bond strength of restorative materials to CAD treated with conventional chemical disinfectants showed superior outcomes compared to photodynamic therapy (aPDT).

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

AIMS AND OBJECTIVES

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.

MATERIALS AND METHODS

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).

CONCLUSION

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 adhesive strength of fiber post-to-canal dentin with Aniline green, Fotoenticine activated by PDT, green tea, and ozone as a final irrigant

AIM

The effect of novel final disinfection protocols Malachite green (MG), Fotoenticine® (FTC), Green tea extract (GTE), and Ozonated water (OW) on the bond strength of prefabricated glass fiber posts (PGFP) adhered to canal dentin.

MATERIAL AND METHOD

The canals of fifty premolars with closed apices were cleansed and obturated. The specimens were randomly assigned to one of five groups based on the final irrigant used, with the control group receiving NaOCl+EDTA and the experimental groups receiving MG, FTC, OW, and GTE. The GFP was cemented with a self-etching, dual-cure paste; the bond strength was estimated with a universal testing machine; and failure analysis was conducted with a stereomicroscope.

RESULTS

The highest PBS was observed in the coronal third of Group 4 (using ozonated water as the final irrigant), whereas the lowest bond integrity was observed in the apical section of Group 2 (1.02-0.54 MPa) using Malachite green as the final irrigant. Group 1, Group 4, and Group 5 exhibited no significant difference in the bond integrity of GFP to dentin when compared to Group 2 (p>0.05). In addition, comparable bond score values were obtained for Groups 2 and 3 (p>0.05).

CONCLUSION

The results of this study suggest that OW and GTE may be effective final disinfectants for root canals, as they increase the bond strength of resin-luting cement.

Different cavity disinfectant efficacy against S.Mutans and shear bond strength of caries affected dentin bonded to resin restoration

AIMS

The existing study aimed to assess the survival rate of S.mutans and shear bond strength (SBS) of resin adhesive restoration bonded to carious affected dentin (CAD) after using different cavity disinfectants (Chitosan, Fotoenticine®, and CO₂ laser) in comparison to Chlorhexidine (CHX).

MATERIALS AND METHODS

The study included human mandibular molars assessed on International Caries Detection and Assessment System (ICDAS) score 4 and 5. The cusp part of the clinical crown was cut off until the reduction reaches the central fossa while being continuously supplied with water coolant till the tooth cementoenamel junction (CEJ). The root sections were embedded in polymethyl methacrylate acrylic resin followed by culturing S.mutans biofilm on the CAD surface. Specimens were arbitrarily allocated into four groups(n = 10) based on the type of disinfection. Group 1 (2% CHX), Group 2 (Chitosan), Group 3 (Fotoenticine), and Group 4 (CO₂ laser). S.mutans survival rate was assessed and CAD was restored with a composite restorative material. Thermoocycling of the samples was performed and a universal testing machine (UTM) and Stereomicroscope were used to identify bond integrity and type of fracture. ANOVA and Tukey multiple comparison tests were used to assess SBS. Data on the survival rate of S. mutans were compared between groups using the nonparametric Kruskal-Wallis test RESULTS: Outcomes revealed that Group 1 (CHX) displayed the highest survival rate (0.65±0.10). However, lowest survival rate was demonstrated by Group 3 (Fotoenticine) treated specimens (0.25±0.06). It was also discovered that CHX unveiled highest bond strength values (21.48±1.39 MPa). Nevertheless, Group 2 (Chitosan) showed lowest SBS (11.01±1.00 MPa). Intergroup comparison analysis presented that group 1, and group 4 (Co2 laser) (17.76±0.41 MPa) displayed no significant difference in their bond integrity achieved. (p>0.05). However, group 3 (Fotoenticine) (16.28±0.51 MPa) and group 2 demonstrated comparable outcomes of SBS. (p>0.05) CONCLUSION: The use of CHX and CO₂ lasers as disinfectants on the CAD surface resulted in a positive impact on the SBS of resin composite, according to the study's findings. However, it is worth noting that Fotoenticine exhibited better antimicrobial efficacy against S. mutans.

Effectiveness of final cavity disinfectant Terminalia chebula, Malachite, and Indocyanine green, against E. faecalis and on the bond interface of fiber post to radicular dentin

AIMS

Evaluation of antimicrobial efficacy of contemporary disinfection Malachite green (MG), Terminalia chebula (T. chebula), and Indocyanine green (ICG)) against E. faecalis and their effect on push-out bond strength (PBS) of glass fiber post (GFP) bonded to root dentin in comparison to conventional irrigation used (Sodium hypochlorite (NaOCl) + Ethylene diamine tetraacetic acid (17% EDTA).

MATERIALS AND METHODS

Root canal treatment was initiated on sixty human single-rooted premolars and working length was established. The canals were enlarged using ProTaper universal system till F3. The prepared canals were obturated with Gutta-percha (GP) and AH Plus sealer followed by post-space preparation. Twenty canals contained a standard strain of E. faecalis (n=5 in each group) cultured overnight at 37 °C in BHI broth. All the samples were randomly allocated into four groups based on post-space irrigation. (n = 10) Group 1: 5.25% NaOCl+17% EDTA (Control), Group 2: 5.25% NaOCl + ICG, Group 3: 5.25% NaOCl + MG and Group 4: 5.25% NaOCl + T. chebula. Survival rates of E. faecalis were evaluated on the twenty specimens. GFP was placed on the remaining samples using self-etch dual-cure pastes and sectioning was performed in 1 mm thick slices. PBS and failure mode were analyzed using a universal testing machine and stereomicroscope. One-way analysis of variance (ANOVA) and Tukey multiple comparison t-tests were used for data analysis. (p = 0.05).

RESULTS

5.25% NaOCl+17% EDTA demonstrated (0.11±0.01 CFU/mL) the lowest survival rate of E. faecalis. However, Group 2 (5.25% NaOCl + ICG) exhibited the highest survival rate (0.52 ± 0.10). Furthermore, the coronal third of group 4 (5.25% NaOCl + T. chebula) (8.71±0.25 MPa) specimens demonstrated the highest PBS of GFP. However, an apical section of group 2 samples (5.25% NaOCl + ICG) (1.21±0.71 MPa) displayed the lowest outcome of bond integrity.

CONCLUSION

Terminalia chebula when used as a final canal disinfectant seems to be promising in improving canal sterility and the bond strength of GFP to the root dentin.