Influence of methylene blue, Riboflavin, and indocyanine green on the bond strength of caries affected dentin when bonded to resin-modified glass ionomer cement

Effect of Resin Cement Viscosities and Surface Roughness on Shear Bond Strength of Conditioned Polymer Infiltrated Ceramic Network

BACKGROUND

Hybrid ceramics bonding with the dentinal substrate is crucial for clinical success and longevity. To enhance adhesion, the surface of ceramic restorations is modified through various conditioning techniques AIM: Effect of Different Surface Conditioners Erbium-doped yttrium aluminum garnet (ER: YAG) laser and Low-level laser therapy (LLLT) activated Methylene blue (MB) on the surface roughness (Ra) and shear bond strength (SBS) of Polymer infiltrating ceramic network (PICN) discs bonded using different viscosity resin cement before and after thermal aging.

MATERIAL AND METHODS

One hundred and fifty human central incisors and one hundred and fifty-three PICN discs were prepared. PICN discs were randomly allocated into three groups based on the surface conditioning(n=51) Group 1:10% HF acid-S, Group 2: LLLT (MB), and Group 3: Er: YAG laser. Following conditioning Ra scores of ten samples were performed. Surface topography of samples was performed using a scanning electron microscope (SEM). Bonding of forty PICN discs from each conditioning group was performed with high (A) or low viscosity (B) dual-curing resin cement (n= 20 each). Each subgroup was divided into two cohorts and subjected to varying storage conditions. The SBS test and failure mode analysis were performed using a universal testing machine and stereomicroscope. Descriptive statistics of SBS and Ra for each group were analyzed using ANOVA and Tukey post hoc tests. HF acid-S attained the highest Ra scores.

RESULTS

Group 1A (HF-S+HIGH) samples achieved the highest SBS values at baseline. Group 3A, on the other hand, displayed the lowest bond score (Er: YAG laser+HIGH) after thermal aging. Intergroup comparison analysis at baseline unveiled that Group 1A and Group 1B (HF(S) + LOW) displayed no significant difference in their bond strength scores (p>0.05). Following artificial aging, it was observed that Group 2A (LLLT (MB) + HIGH) and Group 3A (Er:YAG laser + HIGH) ) presented comparable SBS(p>0.05). Thermal aging decreased SBS significantly in all groups. PICN conditioned with HF-S results in high surface roughness.

CONCLUSION

PICN conditioned with HF acid with silane and bonded with low-viscosity resin cement to the dentinal substrate is preferable. Aging influences SBS.

Experimental and Chitosan-Infused Adhesive with Dentin Pretreated with Femtosecond Laser, Methylene Blue-Activated Low-Level Laser, and Phosphoric Acid

Aim: To prepare experimental adhesive (EA) with 1% and without chitosan nanoparticles on dentin conditioned with a conventional technique phosphoric acid (PA) compared with two different contemporary techniques: photodynamic therapy (PDT) and femtosecond laser (FSL). Method: The methodology consisted of synthesis of EA and 1% chitosan-modified adhesive (CMA). Scanning electron microscopy, dentin adhesive interface assessment, energy-dispersive spectroscopy, shear bond strength (SBS), degree of conversion (DC), and bond failure were assessed. Teeth were selected, disinfected, and mounted in acrylic up to the cementoenamel junction. Occlusal enamel was removed and teeth were randomly allocated into groups and conditioned. These included Group 1: samples treated with PA; Group 2: specimens conditioned with methylene blue photosensitizer (MBP) activated by PDT; and Group 3: samples conditioned with FSL. Following different conditioning regimes, specimens were bonded using 1% CMA and EA. The composite buildup was followed by SBS testing and a bond failure assessment. DC was assessed for both EA and CMA. Analysis of variance and Tukey's post hoc test were used to compare the mean and standard deviation of SBS and DC in different experimental groups, with a significance level of p < 0.05. Results: Dentin pretreated with etch and rinse demonstrated the highest bond strength with 1% CMA. Dentin conditioned with MBP activated by PDT and bonded to EA showed the lowest bond scores. Overall SBS values of 1% CMA were better than EA irrespective of the conditioning regime of dentin. The DC was higher in EA adhesive. This was followed by DC in 1% CMA. DC in EA was found to be comparable with 1% CMA. Conclusions: PA remains the gold standard for dentin conditioning. The incorporation of 1% chitosan in adhesive improves SBS and results in no change in DC. The use of FSL in dentin conditioning can be used as an alternative approach as it results in SBS within acceptable limits. The study was approved by the ethical board of King Saud University.

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.

Orthodontic adhesive loaded with different proportions of ZrO2 silver-doped nanoparticles: An in vitro μTBS, SEM, EDX, FTIR, and antimicrobial analysis

Zirconium dioxide silver-doped nanoparticles (ZrO2AgDNPs) impacts the adhesive material in terms of its physical characteristics, antimicrobial properties, degree of conversion (DC), and micro-tensile bond strength (μTBS) of orthodontic brackets to the enamel surface. A comprehensive methodological analysis utilizing a range of analytical techniques, including scanning electron microscopy coupled with energy-dispersive x-ray spectroscopy (EDX), Fourier-transform infrared (FTIR) spectroscopy, DC analysis, and μTBS testing. A light-curable orthodontic adhesive, specifically Transbond XT, was combined with ZrO2AgDNPs at 2.5% and 5%. As a control, an adhesive with no incorporation of ZrO2AgDNPs was also prepared. The tooth samples were divided into three groups based on the weightage of NPs: group 1: 0% ZrO2AgDNPs (control), group 2: 2.5 wt% ZrO2AgDNPs, and group 3: 5 wt% ZrO2AgDNPs. EDX graph demonstrated silver (Ag), Zirconium (Zr), and Oxygen (O2), The antibacterial efficacy of adhesives with different concentrations of NPs (0%, 2.5%, and 5%) was assessed using the pour plate method. The FTIR spectra were analyzed to identify peaks at 1607 cm-1 corresponding to aromatic CC bonds and the peaks at 1638 cm-1 indicating the presence of aliphatic CC bonds. The μTBS was assessed using universal testing machine (UTM) and bond failure of orthodontic brackets was seen using adhesive remanent index (ARI) analysis. Kruskal-Wallis test assessed the disparities in survival rates of Streptococcus mutans. Analysis of variance (ANOVA) and post hoc Tukey multiple comparisons test calculated μTBS values. The lowest μTBS was observed in group 1 adhesive loaded with 0% ZrO2AgDNPs (21.25 ± 1.22 MPa). Whereas, the highest μTBS was found in group 3 (26.19 ± 1.07 MPa) adhesive loaded with 5% ZrO2AgDNPs. ZrO2AgDNPs in orthodontic adhesive improved μTBS and has acceptable antibacterial activity against S mutans. ZrO2AgDNPs at 5% by weight can be used in orthodontic adhesive alternative to the conventional method of orthodontic adhesive for bracket bonding. RESEARCH HIGHLIGHTS: The highest μTBS was found in orthodontic adhesive loaded with 5% ZrO2AgDNPs. ARI analysis indicates that the majority of the failures fell between 0 and 1 among all investigated groups. The colony-forming unit count of S. mutans was significantly less in orthodontic adhesive loaded with nanoparticles compared with control. The 0% ZrO2AgDNPs adhesive showed the highest DC.

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).

Herbalism and glass-based materials in dentistry: review of the current state of the art

Half a million different plant species are occurring worldwide, of which only 1% has been phytochemically considered. Thus, there is great potential for discovering novel bioactive compounds. In dentistry, herbal extracts have been used as antimicrobial agents, analgesics, and intracanal medicaments. Glass-ionomer cement (GIC) and bioactive glass (BAG) are attractive materials in dentistry due to their bioactivity, adhesion, and remineralisation capabilities. Thus, this review summarizes the evidence around the use of phytotherapeutics in dental glass-based materials. This review article covers the structure, properties, and clinical uses of GIC and BAG materials within dentistry, with an emphasis on all the attempts that have been made in the last 20 years to enhance their properties naturally using the wisdom of traditional medicines. An extensive electronic search was performed across four databases to include published articles in the last 20 years and the search was concerned only with the English language publications. Publications that involved the use of plant extracts, and their active compounds for the green synthesis of nanoparticles and the modification of GIC and BAG were included up to May 2023. Plant extracts are a potential and effective candidate for modification of different properties of GIC and BAG, particularly their antimicrobial activities. Moreover, natural plant extracts have shown to be very effective in the green synthesis of metal ion nanoparticles in an ecological, and easy way with the additional advantage of a synergistic effect between metal ions and the phytotherapeutic agents. Medicinal plants are considered an abundant, cheap source of biologically active compounds and many of these phytotherapeutics have been the base for the development of new lead pharmaceuticals. Further research is required to assess the safety and the importance of regulation of phytotherapeutics to expand their use in medicine.

Hybrid ceramic repair strength, surface roughness, and bond failure, using methylene blue-activated low-level laser therapy, Carbon dioxide, and Ti: Al2O3 laser

AIMS

To evaluate the impact of various pretreatment regimes (LLLT, Ti-sapphire laser, CO2, and HFA-S) on hybrid ceramics, specifically focusing on their ability to enhance repair strength and minimize surface roughness (Ra).

MATERIAL AND METHODS

Discs were made from hybrid ceramics and after disinfection were randomly divided into four groups based on different surface conditioning techniques. Each group consisted of 15 discs, resulting in a total sample size of 60. dics in group 1 was surface treated with Low-level laser therapy (LLLT) using methylene blue (MB), Discs in group 2 with Ti-sapphire laser, Discs in group 3 with CO2 laser, and discs in group 4 with HFA-S. Five samples from each group were assessed for Ra. The remaining 10 samples from each group underwent repair using a porcelain repair kit in adherence to the planned instructions. The bond strength of each sample in all groups was measured using a universal testing machine. Following the bond strength testing, the specimens from all study groups were analyzed to determine the mode of failure. To evaluate the data, a two-way analysis of variance (ANOVA) was used, followed by post hoc multiple comparisons.

RESULTS

The highest repair bond strength was observed in group 4 hybrid ceramics pretreated with HFA-S (19.05±0.79 MPa). The lowest repair bond scores were observed in group 1 hybrid ceramics preconditioned with LLLT in the presence of Photosensitizer (13.41±0.36 MPa). The highest Ra scores were exhibited in group 2 surface treated with Ti-sapphire laser (0.0515±0.16 µm) and the lowest Ra scores were observed in Group 4 HFA-S (0.0311±0.79 µm). Predominant bond failure among different investigated groups was cohesive.

CONCLUSION

The current gold standard for hybrid ceramic conditioning is the use of hydrofluoric acid (HFA) combined with a silane coupling agent. Low-level laser therapy with methylene blue photosensitizer is not recommended for the treatment of hybrid ceramics.

Dentin disinfection and adhesive bond strength using modified photoactivated carbon nanoparticles

AIMS

The present study aimed to investigate the bond integrity and disinfection efficacy of Methylene blue(MB) alone, MB-PDT (Photodynamic therapy), MB@ carbon nanoparticles (CP)-PDT, and Cr, Cr: YSGG (ECL) against lactobacilli in Caries-affected dentin (CAD) MATERIAL AND METHODS: Methods consisted of Shear bond strength (SBS), Scanning electron microscopy (SEM), energy dispersive X-ray (EDX), methods of disinfection, and failure analysis. CAD samples were prepared and biofilm formed on the specimens randomly allocated into five groups based on disinfection. Group 1: CHX; Group 2: MB; Group 3: MB-PDT: group 4: MB@CP-PDT and group 5: ECL. After disinfection Colony forming units were measured and specimens were restored and positioned under a universal testing machine (UTM). Failure analysis was performed using a stereomicroscope. The difference in survival rate was assessed using the Kruskal-Walis test. Mean and standard deviation for bond values after different methods of disinfection was evaluated using analysis of variance (ANOVA) and Post Hoc Tukey. The significance level was p<0.05 RESULTS: Morphological analysis revealed that CPs under SEM are flat discs with edged irregular shapes. EDX analyses show a spike indicating carbon particles by more than 95%. MB@CP-PDT displayed the highest reduction in lactobacillus levels in comparison to the other disinfection methods. The highest SBS was exhibited by the CAD sample disinfected with ECL. The lowest SBS values in CAD specimens after cavity cleansing with MB alone. The predominant failure type in CAD disinfected with MB alone, ECL CHX, MB-PDT, and MB@CP-PDT was adhesive.

CONCLUSION

The use of MB@CP-PDT showed high antibacterial potency against lactobacillus but demonstrated bond values similar to CHX. Use of Er, Cr: YSGG showed considerable effectiveness against lactobacillus along with the highest bond values.

Effect of Malachite green, Ocimum Sanctum, and Er, Cr: YSGG laser on antimicrobial activity against S.mutans and CAD disinfection bonded to resin restoration

AIMS

Evaluation of survival of S.mutans and shear bond strength (SBS) of adhesive restorative material bonded to carious affected dentin (CAD) after using cavity disinfectant i.e., Er, Cr: YSGG (ECYL), (Nd: YAG) (NYL), Malachite green (MG), Ocimum sanctum (OS) in comparison to the conventional control chlorhexidine gluconate (CHX).

MATERIALS AND METHODS

Seventy-five caries-affected mandibular third molars having ICDAS scores 4 and 5 were included. Carious infected dentin was eliminated and CAD surface was obtained. On twenty-five samples, an uncontaminated suspension of S. mutans strain ATCC 35668 in Brain-Heart Infusion broth (BHI) was obtained after 12 hours of incubation at 37°C. Based on the disinfection regime used to sterilize the CAD surface, all the specimens were allocated into five different groups. (n=15) Group 1: CAD disinfected with CHX, Group 2: CAD disinfected with ECYL, Group 3: CAD disinfected with NYL, Group 4: CAD disinfected with MG, and Group 5: CAD disinfected with OS. An assessment of the survival rate of S. mutans was performed. Fifty specimens were smeared with single-step adhesive bond followed by restoring the CAD surface using packable composite. SBS and failure mode were determined using a universal testing machine and stereomicroscope at 40x magnification. ANOVA and post-hoc Tukey-Kramer test was used for data analysis p=0.05 RESULTS: Group 1: CHX-treated specimens displayed the lowest bacterial viability (0.11±0.03 CFU/mL). However, group 4: MG exhibited the highest bacterial survival (0.15 ±0.09 CFU/mL). The highest and lowest SBS of resin adhesive bonded to disinfected CAD surface were exhibited by (group 5: OS) (21.48±1.39 MPa) and (group 3: NYL) (16.41±0.90 MPa) respectively (p>0.05).

CONCLUSION

Ocimum sanctum seems to be promising in terms of its antibacterial efficacy against S.mutans and positive impact on SBS of resin adhesive to CAD surface.

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.

Adhesive bond of Bioactive and bulk fill resin to disinfected caries affected dentin (lactobacillus specie) with laser and photodynamic therapy

AIMS

To evaluate the antimicrobial effectiveness of cavity disinfectants chlorhexidine gluconate (CHX), Er, Cr, YSGG laser (ECL), and curcumin photosensitizer (CP) against Lactobacillus and shear bond strength (SBS) of Bioactive (BA) and bulk fill composite (BFC) restorative material bonded to carious affected dentin (CAD).

MATERIALS AND METHODS

Sixty human mandibular molars scored 4 and 5 on the International Caries Detection and Assessment System (ICDAS) were included. After inoculating the specimens with lactobacillus specie all the samples were arbitrarily divided into three groups based on the disinfection regime used (n=20). Groups 1 and 2: CAD disinfection using ECL, Groups 3 and 4: CAD disinfection using CP, and Groups 5 and 6: CAD disinfection using CHX. After cavity sterilization, the survival rate was estimated and each group was further divided into two sub-groups based on the restorative material used. Groups 1, 3, and 5 (n = 10) were restored using BFC restorative material, and groups 2, 4, and 6 (n = 10) were restored using a conventional bulk-fill resin material. A universal testing machine (UTM) was used to determine the SBS and debonded surfaces were examined under a stereomicroscope to determine the modes of failure. Kruskal-Walis, ANOVA, and Post Hoc Tukey were applied to investigate the survival rate and bond strength values.

RESULTS

ECL group displayed the highest survival rate (0.73±0.13) of Lactobacillus. The least survival rate (0.17±0.09) was demonstrated by CP activated by PDT. Group 1 (ECL+ BA) treated specimens exhibited the maximum value of SBS (18.31 ± 0.22 MPa). However, group 3 (CP + BA) revealed the minimum values of bond strength (14.05 ± 1.02 MPa). The intergroup comparison revealed that group 1, group 2 (ECL+BFC) (18.11 ± 0.14 MPa), group 5 (CHX+ BA) (18.14 ± 0.36 MPa), and group 6 (CHX+BFC) (18.18 ± 0.35 MPa) displayed comparable outcomes of bond integrity (p>0.05).

CONCLUSION

Caries-affected dentin disinfected with Er, Cr: YSGG, and chlorhexidine improve bond scores of bioactive and conventional bulk-fill restorative material.

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.

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

AIM

To assess the impact of new cavity sterilization types using ozone water (OW), Potassium Titanyl Phosphate laser (KTPL), Triphala, and indocyanine green photosensitizer (ICGP) on adhesive bond strength.

MATERIALS AND METHODS

Fifty human permanent molars were included based on the criteria of International Caries Detection and Assessment System (ICDAS) scores 4 and 5 visual examinations, surface hardness valuation, staining by a caries detector solution, and radiographs. Caries-affected dentin (CAD) samples were randomly distributed into groups based on methods of disinfection (n = 10). Group 1: chlorhexidine, group 2: ow, group 3: KTPL, group 4: Triphala, and group 5: ICGP. Following disinfection, specimens were applied with Adper prime and bond NT and then restored with resin composite. All specimens were positioned in a jig of the universal testing machine for shear bond strength (SBS). The debonded samples were analyzed under a stereomicroscope at 40x magnification to determine the type of failure. Analysis of variance (ANOVA) and Tukey HSD tests were used keeping the level of significance p < 0.05.

RESULTS

The highest bond of adhesive resin was displayed by group 2 specimens cleaned using OW (16.71 ± 0.19 MPa). Whereas, the lowest bond integrity was observed by group 5 specimens disinfected using ICGP (11.21 ± 0.16 MPa). It was observed samples disinfected with OW (16.71 ± 0.19 MPa) in group 2 and samples in group 4 (16.09 ± 0.26 MPa) treated with Triphala displayed comparable outcomes of bond strength (p > 0.05). It was observed that group 2 (70%) and 4 (80%) treated specimens accounted mostly for cohesive failure. However, groups 1 (80%), 3 (60%), and 5 (70%) displayed an adhesive failure pattern.

CONCLUSION

OW and Triphala displayed better bond integrity of adhesive resin to CAD and therefore have the potential to be used as a cavity disinfectant in clinical settings. However, ICGP and KTPL displayed weak bonds of adhesive to CAD. More work is needed to extrapolate the findings of the present study.