Dentin Erosion Research Articles

The Ways of Forming and the Erosion/Decay/Aging of Bioapatites in the Context of the Reversibility of Apatites.

This study primarily focused on the acid erosion of enamel and dentin. A detailed examination of the X-ray diffraction data proves that the products of the acid-caused decay of enamel belong to the family of isomorphic bioapatites, especially calcium-deficient hydroxyapatites. They are on a trajectory towards less and less crystallized substances. The increase in Bragg's parameter d and the decrease in the energy necessary for the changes were coupled with variability in the pH. This was valid for the corrosive action of acid solutions with a pH greater than 3.5. When the processes of natural tooth aging were studied by X-ray diffraction, a clear similarity to the processes of the erosion of teeth was revealed. Scarce data on osteoporotic bones seemed to confirm the conclusions derived for teeth. The data concerning the bioapatite decays were confronted with the cycles of apatite synthesis/decay. The chemical studies, mainly concerning the Ca/P ratio in relation to the pH range of durability of popular compounds engaged in the synthesis/decay of apatites, suggested that the process of the formation of erosion under the influence of acids was much inverted in relation to the process of the formation of apatites, starting from brushite up to apatite, in an alkaline environment. Our simulations showed the shift between the family of bioapatites versus the family of apatites concerning the pH of the reaction environment. The detailed model stoichiometric equations associated with the particular stages of relevant processes were derived. The synthesis processes were alkalization reactions coupled with dehydration. The erosion processes were acid hydrolysis reactions. Formally, the alkalization of the environment during apatite synthesis is presented by introducing Ca(OH)2 to stoichiometric equations.

Impact of Tulsi extract on sealer penetration in dentinal tubules as compared to 17% EDTA as the final root canal irrigant (in vitro analysis)

Introduction: Penetration of endodontic sealers into dentinal tubules is essential for ensuring successful root canal treatment by creating a hermetic seal that prevents reinfection. Traditionally, 17% EDTA has been used as the final irrigant for smear layer removal. However, concerns regarding its limited antimicrobial properties and potential for dentin erosion have prompted the exploration of alternative solutions. This in vitro study compared the effectiveness of Tulsi extract with that of 17% EDTA in promoting sealer penetration within the dentinal tubules. Methodology: Thirty extracted single-rooted teeth were randomly divided into three groups: Group 1, 17% EDTA; Group 2, Tulsi extract; and Group 3, saline control. After preparation, the root canals were irrigated with their respective soluti ons, filled with gutta-percha, and sealed with a calcium hydroxide-based sealer. Sealer penetration was analyzed using scanning electron microscopy (SEM) at the 2 mm and 5 mm levels from the root apex. Results: The results showed no significant difference in sealer penetration at 2 mm among all the groups. However, at 5 mm, both EDTA and Tulsi groups exhibited significantly greater sealer penetration than the control group (p < 0.001). No significant difference was observed between the EDTA and Tulsi groups at 5 mm (p = 0.706). Conclusion: Tulsi extract demonstrated similar efficacy to 17% EDTA in facilitating sealer penetration, suggesting its potential as a biocompatible and antimicrobial alternative for root canal irrigation protocols. Further studies are warranted to explore its clinical applications and commercial viability.

Preventing dentin erosion with silver diamine fluoride and salivary pellicle: an in vitro study

ObjectivesTo investigate the preventive and discoloring effects of a single and two weekly applications of 38% silver diamine fluoride (SDF) against dentin erosion.Materials and methods180 dentin blocks were divided into four groups. Group 1 (SDF2) received two weekly applications of 38% SDF. Group 2 (SDF1) received a single application of 38% SDF. Group 3 (SNF) received a daily application of stannous chloride/amine fluoride/sodium fluoride (standard of care for dental erosion). Group 4 (DW) received a daily application of deionized water. The treated blocks were subjected to a 14-day erosive challenge. Crystal characteristics, elemental composition, surface morphology, percentage of surface microhardness loss (%SMHL), surface loss, and color change (ΔE) were investigated using X-ray diffraction (XRD), energy-dispersive spectrometry (EDS), scanning electron microscopy (SEM), hardness testing, profilometry, and digital spectrophotometry, respectively.ResultsXRD and EDS showed dentin surfaces had silver compounds in SDF2 and SDF1, and stannous chloride in SNF. SEM revealed less dentin demineralization with tubular occlusion in SDF2, SDF1, and SNF, but severe demineralization in DW. The %SMHL of SDF2, SDF1, SNF, and DW were 10.8 ± 2.1, 15.7 ± 2.1, 17.9 ± 2.1, and 28.7 ± 2.0 (SDF2 < SDF1 < SNF < DW, p < 0.05). Surface loss (µm) of SDF2, SDF1, SNF, and DW were 5.0 ± 0.6, 6.0 ± 0.6, 6.0 ± 0.7, and 9.0 ± 0.5 (SDF2 < SDF1 = SNF < DW, p < 0.001). ΔE of SDF2, SDF1, SNF, and DW were 26.0 ± 3.4, 12.1 ± 3.8, 6.9 ± 3.5, and 3.9 ± 3.6 (SDF2 > SDF1 > SNF = DW, p < 0.001).Conclusion38% SDF with two weekly applications provided better preventive effects against dentin erosion, but it might discolor dentin.Clinical relevanceThe increased 38% SDF application showed a better anti-erosive potential against dentin erosion. However, SDF caused black staining on the dentin.

Smear Layer Removing and Pulp Dissolving Ability of Sodium Hypochlorite Mixed with Two Etidronate-Containing Irrigants in Continuous Chelation Technique

The study aimed to assess the effect of two etidronate-containing irrigants and EDTA on the ability of sodium hypochlorite (NaOCl) to remove the smear layer and dissolve organic tissues. This study evaluated the following solutions: distilled water, 3% NaOCl, 3% NaOCl + EDTA, and 3% NaOCl mixed with etidronate powder from two manufacturers [Dual Rinse, (DR); IsraDent, (ID)] to obtain 9%, 15%, and 18% solutions. To assess the proteolytic activity, bovine muscle tissue samples (56.1 ± 5.4 mg; n = 10 per group) were immersed in the tested solutions for 15 min. Absolute weight changes and percentages of weight changes (wt%) were calculated. To assess smear layer removal, the root canals of human wisdom teeth were instrumented, irrigated with the tested solutions (n = 10 per group), and evaluated using SEM. Statistical analysis employed an ANOVA with a post-hoc Tukey test and paired t-test, the Kruskal–Wallis test with a pairwise Wilcoxon rank sum test, and the Friedman test with a pairwise Wilcoxon signed-rank test. The mean weight loss in the NaOCl group comprised 17.3 mg (32 wt%). Sequential use of NaOCl and EDTA resulted in a significant increase in proteolytic activity of the former (57 wt%), while mixing these solutions led to a reduction of proteolytic activity (17 wt%). All NaOCl/DR groups exhibited a significantly greater dissolution activity than that of NaOCl alone, with the mean weight loss ranging from 23.3 mg (40 wt%) to 24 mg (41 wt%). ID9% and ID15% significantly decreased the proteolytic activity of NaOCl. In most groups, the apical thirds of the root canals demonstrated a significantly heavier smear layer compared to the middle and coronal thirds. The most effective smear layer removal was observed after irrigation with NaOCl combined with EDTA or DR (all concentrations); however, in the NaOCl + EDTA and DR18% groups, it was accompanied by moderate to severe erosion. Irrigation with ID did not result in smear layer removal or dentin erosion. In conclusion, the smear layer removal and pulp dissolving effects of continuous chelation using etidronate were manufacturer/composition-dependent. DR9% combined with NaOCl demonstrated the most promising results.

Evaluation and comparison of the efficiency of ultrasonically activated intracanal irrigants grapeseed and pineapple extract in removing smear layer from the apical third of the root canal: An in vitro SEM analysis

ABSTRACT Aim: This study aims to evaluate and compare the efficiency of grapeseed and pineapple extract in removing smear layer from the apical third of root canal, with and without ultrasonic activation. Methods: Eighty single-rooted permanent teeth were divided into two main groups: Group I: conventional syringe irrigation and Group II: ultrasonic activation. Each group was subdivided into two experimental groups, i.e. grapeseed and pineapple extract and one control group, i.e., 17% ethylenediaminetetraacetic acid (EDTA). For each subgroup, instrumentation was done using ProTaper Gold up to size F3 and irrigated with 5 mL of the respective irrigant, followed by a final rinse of 2.5 mL of 5.25% NaOCl. For Group II, the respective irrigant was ultrasonically activated for 1 min, followed by a final rinse of 2.5 mL of 5.25% NaOCl. Smear layer evaluation was done with scanning electron microscope, and data were statistically analyzed. Results: In Group I, both pineapple and grapeseed extracts were more effective than 17% EDTA in removing smear layer from the apical root canal. However, in Group II, 17% EDTA showed highest efficacy in smear layer removal, followed by pineapple and grapeseed extracts (P &lt; 0.05). Conclusion: Natural extracts such as pineapple and grapeseed seeds extracts exhibit potential for smear layer removal in the apical third, without the disadvantage of dentinal erosion from synthetic smear layer removing agents.

Protecting primary teeth from dental erosion through bioactive glass

ObjectivesThe present study aimed to evaluate the effectiveness of bioactive glass (BAG) in preventing dental erosion in primary teeth. MethodsEnamel and dentin specimens (2 × 2 × 2 mm) were obtained from extracted primary teeth, which were randomly divided into the following groups based on the pretreatments (n = 12): DW (deionized water), NaF (2 % sodium fluoride), 2BAG (2 % BAG), 4BAG (4 % BAG), 6BAG (6 % BAG), and 8BAG (8 % BAG). The specimens were immersed in the respective solutions for 2 min and subjected to in vitro erosive challenges (4 × 5 min/d) for 5 d. The erosive enamel loss (EEL), erosive dentin loss (EDL), and the thickness of the demineralized organic matrix (DOM) were measured using a contact profilometer. The surface microhardness (SMH) was measured, and the percentage of SMH loss (%SMHL) was calculated. The surface morphology and mineral composition were evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. ResultsAfter the erosive challenges, the EEL, EDL, and%SMHL of the 2BAG, 4BAG, 6BAG, and 8BAG groups significantly reduced, with the greatest reduction was observed in the 6BAG (EEL: 6.5 ± 0.2 μm;%SMHL in enamel: 12.8 ± 2.6; EDL: 7.9 ± 0.3 μm; %SMHL in dentin: 22.1 ± 2.7) and 8BAG groups (EEL: 6.4 ± 0.4 μm;%SMHL in enamel: 11.0 ± 1.9; EDL: 7.8 ± 0.5 μm; %SMHL in dentin: 22.0 ± 2.5) (P < 0.05). With increasing BAG concentrations, the number of surface deposits containing Ca, P, and Si increased. Conclusions6BAG was the most effective for preventing dental erosion in primary teeth and showed a particularly strong potential for dentin erosion prevention. Clinical SignificanceBioactive glass, especially at a 6 % concentration, has proven effective in reducing erosive tooth wear and surface microhardness loss while also protecting demineralized organic matrix in primary dentin.

In Vitro Evaluation of Remineralization Potential of Five Toothpastes on Soft Drink-Eroded Human Enamel and Dentine.

The purpose of this in vitro study was to evaluate the potential remineralization of enamel and dentine erosion lesions after the application of five different toothpastes. A total of 104 enamel and dentine samples were prepared from maxillary third molars. Each group was divided according to the toothpaste application mode (topical = 56; brushing = 48) and the toothpaste used seven topical groups and six brushing groups (n = 8). The groups included negative control (NC), positive control (PC), Sensodyne Pronamel (SP), Regenerate (R), Regenerate with boosting serum (R+), Colgate Duraphat 5000 (CD), and tooth mousse (TM). The statistical analysis showed significant surface microhardness (SMH) change. All enamel groups showed a significant decrease in SMH compared to NCfor both application modes. However, no significance was recorded between test groups. Similar results were observed between dentine groups and their relevant controls for both application modes, except brushed Rand R+groups, which were insignificant to their NC. For topical groups, TMshowed a significant increase in SMH. While Rand R+showed lower loss than SPand CD. All tested agents offered a degree of remineralization in both enamel and dentine with no significant difference between agents in enamel groups while R, R+, and TMoffered better results in dentine groups. For dentine groups, similar findings were observed with superior tooth surface protection with the application of TM over other agents. Tooth surface remineralization was achieved when agents were either applied topically or brushed over the surface.

Antimicrobial action, cytotoxicity and erosive potential of hypochlorous acid obtained from an electrolytic device compared with sodium hypochlorite.

This study aimed to compare the antimicrobial action, cytotoxicity, cleaning ability, and erosion of dentine of hypochlorous acid (HClO) obtained from an electrolytic device at two different concentrations (Dentaqua) and three concentrations of sodium hypochlorite (NaOCl). Microbiological test-The root canals of sixty single-rooted extracted human teeth were inoculated with Enterococcus faecalis and divided into 6 groups (n = 10), according to decontamination protocol: DW (control); 1% NaOCl; 2.5% NaOCl; 5.25% NaOCl; 250 ppm HClO and 500 ppm HClO. The colony-forming units were counted to evaluate the decontamination potential of each group, calculating the reduction in bacterial percentage. Cytotoxicity test-Cytotoxicity was evaluated after inoculation of the same tested protocols in fibroblastic cells for 3 min, calculating the cell viability percentages. Specifical statistical analysis was performed (α = 5%). Cleaning ability and erosion-Fifty-six single-rooted bovine lower incisors were divided into seven groups of 8 roots each, being the test groups 1% NaOCl; 2.5% NaOCl; 5,25% NaOCl; 250 ppm HClO and 500 ppm HClO, and a negative and positive control. Negative control was not contaminated, and the other groups were inoculated with Enterococcus faecalis. SEM images were ranked as from the cleanest to the least clean. Erosion was also assessed, being ranked from the least to the most eroded dentine. The highest bacterial reduction was observed in experimental groups, with no statistical differences between them (p > 0.05). The highest number of viable cells was observed in control group, followed by 250 ppm HClO and 500 ppm HClO groups, with statistical differences between them (p < 0.05). 1% NaOCl; 2.5% NaOCl; 5.25% NaOCl and 500 ppm HClO displayed the cleanest areas. All sodium hypochlorite groups displayed erosion with higher ranks with greater concentration, while hypochlorous acid did not display any erosion regardless the concentration. It is possible to conclude that HClO obtained from an electrolytic device presented high antimicrobial activity and low cytotoxicity in both tested concentrations. 500 ppm HClO did not display erosion and showed great cleaning ability. The use of 500 ppm hypochlorous acid may reduce unfavorable behavior of sodium hypochlorite whilst maintaining its antimicrobial action.

Efficacy of Three Remineralizing Agents on Erosion of Root Dentin by Cola Drink: An In Vitro Study

Abstract Objective The aim of the study was to investigate the effects of silver diamine fluoride (38% SDF), sodium fluoride (NaF) varnish, and casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) on cola-eroded root dentin microhardness and mineral alteration in vitro. Materials and Methods Forty human root dentin slabs were exposed to alternating 10 cycles of cola drink and artificial saliva, repeated 3 times at 6-hour intervals. Specimens were randomly assigned to four groups: control (deionized water), 38% SDF, NaF varnish, and CPP-ACPF. All specimens underwent the second erosion process. Microhardness was measured at baseline (KHN0), pretreatment (KHN1), and posttreatment (KHN2). The mean difference of microhardness (ΔKHN2-1) was analyzed using one-way analysis of variance (ANOVA) and Tukey's post hoc tests (α = 0.05). The chemical composition and surface morphology were assessed using energy dispersive spectroscopy (EDS) and scanning electron microscope (SEM). Results All experimental groups exhibited dentinal tubule occlusion. Both 38% SDF and NaF varnish demonstrated a statistically significant increase in microhardness compared to CPP-ACPF. However, CPP-ACPF was comparable to the control group. EDS analysis showed an increase in weight percentage of fluorine in all groups. Furthermore, silver and chlorine were detected in the 38% SDF group. Conclusion All treatments enhanced eroded root dentin microhardness, with 38% SDF and NaF varnish demonstrating superior acid resistance and preventing morphological changes induced by cola re-immersion.

Enhancing the inhibition of dental erosion and abrasion with quercetin-encapsulated hollow mesoporous silica nanocomposites.

Introduction: Dental erosion and abrasion pose significant clinical challenges, often leading to exposed dentinal tubules and dentine demineralization. The aim of this study was to analyse the efficacy of quercetin-encapsulated hollow mesoporous silica nanocomposites (Q@HMSNs) on the prevention of dentine erosion and abrasion. Method: Q@HMSNs were synthesized, characterized, and evaluated for their biocompatibility. A total of 130 dentine specimens (2mm × 2mm × 2mm) were prepared and randomly distributed into 5 treatment groups (n = 26): DW (deionized water, negative control), NaF (12.3mg/mL sodium fluoride, positive control), Q (300μg/mL quercetin), HMSN (5.0mg/mL HMSNs), and Q@HMSN (5.0mg/mL Q@HMSNs). All groups were submitted to in vitro erosive (4 cycles/d) and abrasive (2 cycles/d) challenges for 7days. The specimens in the DW, NaF, and Q groups were immersed in the respective solutions for 2min, while treatment was performed for 30s in the HMSN and Q@HMSN groups. Subsequently, the specimens were subjected to additional daily erosion/abrasion cycles for another 7days. The effects of the materials on dentinal tubule occlusion and demineralized organic matrix (DOM) preservation were examined by scanning electron microscopy (SEM). The penetration depth of rhodamine B fluorescein into the etched dentine was assessed using confocal laser scanning microscopy (CLSM). The erosive dentine loss (EDL) and release of type I collagen telopeptide (ICTP) were measured. The data were analysed by one-way analysis of variance (ANOVA) with post hoc Tukey's test (α = 0.05). Results: Q@HMSNs were successfully synthesized and showed minimal toxicity to human dental pulp stem cells (HDPSCs) and gingival fibroblasts (HGFs). Q@HMSNs effectively occluded the dentinal tubules, resulting in a thicker DOM in the Q@HMSN group. The CLSM images showed more superficial penetration in the HMSN and Q@HMSN groups than in the quercetin, NaF, and DW groups. The Q@HMSN group exhibited a significantly lower EDL and reduced ICTP levels compared to the other groups (p < 0.05). Conclusion: Q@HMSNs hold promise for inhibiting dentine erosion and abrasion by promoting tubule occlusion and DOM preservation.

The effect of final irrigation with different solutions on smear layer removal and dentin erosion: A scanning electron microscope study.

This study aimed to compare the effectiveness of initial irrigation with sodium hypochlorite (NaOCl) and final irrigation with QMix, 40% citric acid, and 17% ethylenediaminetetraacetic acid (EDTA) on smear layer removal and dentin erosion. Forty extracted human mandibular premolar teeth were randomly divided into four groups (n = 10) according to the type of final irrigants used: 17% EDTA, QMix, citric acid, and control (normal saline). Canals were mechanically prepared using ProTaper Next instruments to an apical size of X3. Subsequently, the roots were sectioned in a buccolingual direction. Scanning electron microscopy (SEM) was used to assess the presence of the smear layer and the amount of dentin erosion in the coronal, middle, and apical thirds of the root canals. In regards to smear layer removal, there was a significant difference between the control group and the other tested groups. Moreover, it was significantly higher in the coronal and middle thirds than in the apical third. However, there were no significant differences between the groups of EDTA, QMix, and citric acid. Concerning dentin erosion, citric acid produced significantly more dentin erosion than the other tested groups. Final irrigation with solutions had a higher ability to remove the smear layer in the coronal and middle thirds compared to the apical third. Of all the solutions tested, 40% citric acid had the most pronounced impact on dentin erosion, followed by 17% EDTA and QMix.

Scanning electron microscopic analysis of 5% glycolic acid as a novel alternative to 17% ethylenediaminetetraacetic acid in root biomodification: An in vitro study.

Nonsurgical periodontal therapy results in the formation of a smear layer which inhibits tissue regeneration. Root biomodification (RB) using various agents has been tried for the enhancement of new attachment formation. However, no substantial therapeutic advantages of currently available root conditioning agents have been reported emphasizing the need for additional biologically acceptable agents. Glycolic acid (GA) due to its antimicrobial nature and ability of initiation and proliferation of fibroblasts may potentially modify root surface enabling regeneration. Eighty specimens from 40 single-rooted teeth were treated with 17% ethylenediaminetetraacetic acid (EDTA) and 5% GA and scanning electron microscopy analysis was done. The micrographs were examined for the evaluation of smear layer removal, total number of dentinal tubules, total number of patent dentinal tubules, mean diameter and surface area of dentinal tubules, and dentin erosion. Statistical analysis was done using unpaired t-test for intergroup comparison. The efficacy of smear layer removal (P = 0.01) and dentin erosion (P = 0.042) was significantly better in the GA group. Both the groups showed no difference in dentinal tubule-related parameters. GA showed improved RB with greater smear layer removal and lesser dentin erosion, indicating its use as a potent alternative to the conventional EDTA root conditioning.

Comparative Evaluation of the Effect of Different Chelating Agents on Mineral Content and Erosion of Radicular Dentine: A FESEM-EDS Analysis.

Irrigating solutions play an important role in the debridement and disinfection of the root canal space, and thus, it is crucial to comprehend their effects on the composition and surface structure of radicular dentine. This study evaluated and compared the effects of 17% ethylenediaminetetraacetic acid (EDTA), 9% 1-hydroxyethylidene-1,1-bisphosphonate (HEBP) and 0.2% chitosan on the mineral content and erosion of radicular dentine when used as a final rinse. Sixty extracted human mandibular premolar teeth were decoronated and instrumented to ProTaper size F2. After final instrumentation, the samples were randomly divided into 4 groups (n=15) according to the type of final irrigant used: Normal saline (control), 17% EDTA, 9% HEBP and 0.2% chitosan. Field emission scanning electron microscopy was used to assess the erosion of radicular dentine, and energy dispersive X- ray spectroscopy was used to quantify the radicular dentine mineral composition at the coronal, middle and apical levels of all the prepared samples after final irrigation. The one-way analysis of variance was used for intra-group and inter-group comparisons of means, the Kruskal Wallis test for intra-group and inter-group comparisons of medians and Tukey's post hoc test for pairwise comparisons. There was no significant difference in the levels of calcium (Ca), phosphorus (P) and Ca/P ratio after final rinse with 17% EDTA, 9% HEBP and 0.2% chitosan at all three root levels (p>0.05); except at the coronal level, where 0.2% chitosan caused significantly less alteration in Ca levels and Ca/P ratio than 17% EDTA and 9% HEBP respectively (p<0.05). 17% EDTA, 9% HEBP and 0.2% chitosan caused no erosion at the middle and apical levels. Meanwhile, 17% EDTA and 9% HEBP caused moderate erosion at the coronal level. Alternatives to 17% EDTA during final irrigation can be 9% HEBP and 0.2% chitosan. (EEJ-2023-06-078).

Dentin erosive wear is reduced by fluoride varnishes containing nanosized sodium trimetaphosphate in vitro.

This study evaluated the effect of fluoride varnishes containing micrometric or nanosized sodium trimetaphosphate (TMP) on dentin erosive wear in vitro. Bovine root dentin blocks were selected by surface hardness and randomly divided into five experimental groups/varnishes (n = 20/group): placebo, 5% sodium fluoride (NaF); 5% NaF+5% micrometric TMP; 5% NaF+2.5% nanosized TMP; and 5% NaF+5% nanosized TMP. Half of the surface of all blocks received a single application of the assigned varnish, with subsequent immersion in artificial saliva for 6 h. Varnishes were then removed and the blocks were immersed in citric acid (90 s, 4×/day, 5 days). After each erosive cycle, ten blocks of each group were immersed in a placebo dentifrice for 15 s (ERO), while the other ten blocks were subjected to abrasion by brushing (ERO+ABR). Dentin erosive wear was assessed by profilometry. Data were submitted to 2-way ANOVA and to the Holm-Sidak test (p<0.05). Dentin erosive wear was significantly higher for ERO+ABR than for ERO for all varnishes. TMP-containing varnishes promoted superior effects against dentin erosive wear compared with 5% NaF alone; and 5% nanosized TMP led to the lowest wear among all varnishes. In conclusion, the addition of TMP to conventional fluoride varnish (i.e., varnish containing only NaF) enhanced its protective effects against bovine root dentin erosion and erosion+abrasion. Additionally, the use of 5% nanosized TMP led to superior effects in comparison to 5% micrometric TMP, both for erosion and erosion+abrasion in vitro.

Update on chelating agents in endodontic treatment: A systematic review.

The aim of this review was to assess the evidence regarding the most commonly used chelating agents in terms of efficacy, erosive potential, cytotoxicity, interaction, antimicrobial effect, impact on sealers adhesion, and release of growth factors. MEDLINE (PubMed) database, Cochrane Library and Scopus were searched up to January 14, 2023, including studies with one or more of the following chelating agents: 17% EDTA, 9% and 18% HEDP, 10% and 20% citric acid, 2%-2.25% peracetic acid and 7% maleic acid. In addition, the reference lists of all selected articles were also checked to identify additional relevant studies. Articles published in English and available in full-text were selected. The quality of studies was assessed using the modified CONSORT checklist guide and the Cochrane Collaboration tool. The electronic search yielded 538 citations, 56 of which were included. The articles included had moderate and low evidence values. Among 56 articles included, 55 were in vitro studies and one was a randomized clinical trial. Among the in vitro studies, 15 evaluated efficacy and dentin erosion, 12 evaluated interaction with other endodontic irrigants, 9 tested antimicrobial effect, 4 evaluated cytotoxicity in hamster and rat lung cells, 9 evaluated intervention in adhesion of filling materials and 8 focused on release of growth factors and on behavior of stem cells in regenerative endodontic. The RCT tested antimicrobial effect. 17% EDTA is the most effective in smear layer removal and in releasing growth factors on regenerative endodontics. However, the current incorporation of 9% and 18% etidronic acid has shown optimal results due to its compatibility with sodium hypochlorite and its capability on avoiding smear layer formation through a continuous chelation action. Despite these preliminary findings, methodological standardization between studies is required and in vivo studies are necessary to confirm in vitro studies. Key words:Chelating Agents, Smear Layer, Systematic Review, Endodontics, Root Canal Irrigants.

The activity, distribution, and colocalization of cathepsin K and matrix metalloproteases in intact and eroded dentin.

This study aimed to assess the activity, distribution, and colocalization of cathepsin K (catK) and matrix metalloproteases (MMPs) in both intact and eroded dentin in vitro. Eroded dentin was obtained by consecutive treatment with 5% citric acid (pH = 2.3) for 7days, while intact dentin remained untreated. Pulverized dentin powder (1.0g) was extracted from both intact and eroded dentin using 5mL of 50mM Tris-HCl buffer (0.2g/1mL, pH = 7.4) for 60h to measure the activity of catK and MMPs spectrofluorometrically. In addition, three 200-μm-thick dentin slices were prepared from intact and eroded dentin for double-labeling immunofluorescence to evaluate the distribution and colocalization of catK and MMPs (MMP-2 and MMP-9). The distribution and colocalization of enzymes were analyzed using inverted confocal laser scanning microscopy (CLSM), with colocalization rates quantified using Leica Application Suite Advanced Fluorescent (LAS AF) software. One-way analysis of variance (ANOVA) was used to analyze the fluorescence data related to enzyme activity (α = 0.05). The activity of catK and MMPs was significantly increased in eroded dentin compared with intact dentin. After erosive attacks, catK, MMP-2, and MMP-9 were prominently localized in the eroded regions. The colocalization rates of catK with MMP-2 and MMP-9 were 13- and 26-fold higher in eroded dentin, respectively, than in intact dentin. Erosive attacks amplified the activity of catK and MMPs in dentin while also altering their distribution patterns. Colocalization between catK and MMPs increased following erosive attacks. CatK, MMP-2, and MMP-9 likely play synergistic roles in the pathophysiology of dentin erosion.

Supplementation of Energy Drinks with Green Tea Extract: Effect on In Vitro Abrasive/Erosive Dentin Wear.

To investigate the effect of the supplementation of energy drinks with green tea extract on abrasive and erosive dentin wear. Six groups, each comprising 15 bovine dentin samples, were prepared, yielding a total of 90 samples. Erosion was performed by immersing the samples in Red Bull and Red Bull light with and without green tea extract. Tap water with and without green tea extract was used as the control groups. The samples were subjected to abrasive/erosive cycling for five days. The following cycling was performed daily: toothbrush abrasion (20 brushstrokes; 2.5 N); eight erosive cycles (2 min storage in the respective solutions); in between the erosive cycles, storage in artificial saliva (60 min) and again toothbrush abrasion (20 brushstrokes; 2.5 N). During the night, samples were again stored in artificial saliva. Abrasive/erosive dentin wear was measured using a stylus profilometer (µm, accuracy = 40 nm). The measured dentin loss results from the vertical position shift on the y-axis from base to final profile after the wear process in 2D. Pairwise comparisons between the groups were carried out using Wilcoxon signed-rank test. The following dentin wear (median [IQR]) was measured: Red Bull: 1.9 µm (0.5); Red Bull Light: 1.3 µm (0.3); Red Bull with green tea extract: 0.8 µm (0.3); Red Bull Light with green tea extract: 0.3 µm (0.5); Tap water with green tea extract: -0.2 µm (0.7); Tap water: -1.0 µm (1.2). The comparison of all tested groups to each other proved to be statistically significant (p < 0.05). The supplementation of energy drinks with green tea extract provide a protective effect against erosive/abrasive wear in vitro.

Smear Layer Removal Efficacy of EDTA and Citric Acid in Endodontics

Introduction: Smear layer is formed by organic and inorganic components generated during endodontic instrumentation. Smear layer has many deleterious effects on the success of root canal treatment. So removal of smear layer is advocated. Sodium Hypochlorite (NaOCl) and a chelating agent like Ethylene Diamine Tetra Acetic Acid (EDTA) or Citric Acid is commonly used alternatively to remove smear layer. But the alternate use increase dentine erosion in root canal surface. This in vitro study attempts to compare the smear layer removal efficacy of 15% EDTA &amp; 10% Citric Acid as a final rinsing solution. Materials and Methods: Forty extracted, single rooted and single canal human anterior tooth were used. Endodontic preparation of the root canal was done after grouping and access cavity preparation. Final irrigation was given with 15% EDTA &amp; 10% Citric Acid to the test groups and distilled water control groups and kept for one minute. Photomicrograph of the root canal surface at 3000X magnification at coronal, middle and apical regions were taken with the help of SEM and scoring for smear layer removal was done. Data was analyzed using SPSS version 16 and were compared with the control samples and subjected to statistical analysis by one way ANOVA and Bonferroni multiple comparison tests at 5% level of significance. Result: The test solutions removed smear layer but none could be removed completely from all of the three root canal regions. 10% Citric Acid removed smear layer better from the coronal and middle region but in apical region 15% EDTA produced a better result. The difference of smear layer removal efficacy of 15% EDTA &amp; 10% Citric Acid with the Control solution was found statistically significant (p&lt;0.001) but in between 15% EDTA &amp; 10% Citric Acid it was not significant in all three root canal regions. Conclusion: Regarding the smear layer removal efficacy of 10% Citric Acid was found better as a final rinse solution. Update Dent. Coll. j: 2023; 13(2):9-14

The potential of galactomannan from Caesalpinia ferrea on erosive dentin wear reduction in vitro.

Gels containing juca seed galactomannan (JSG) were evaluated for their potential to prevent the progression of dentin erosive wear in an in vitro study with four experimental groups (n = 9). The treatments included distilled water (DW), 0.05% stannous fluoride (121 ppm F), and 0.5% or 1% JSG. The specimens underwent a cycle (3 times/day) consisting of immersion in 1% citric acid (5 minutes), treatment (5 minutes), and artificial saliva exposure (2 hours/overnight) for 5 days. Surface changes were assessed using mechanical profilometry (wear), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The data were analyzed using ANOVA followed by Tukey's post-test (p < 0.05). The negative control group exhibited the highest wear (6.0 µm ± 3.5), significantly differing from the group treated with 0.05% stannous fluoride gel (p = 0.007), which showed less dentin loss. The groups treated with 0.5% and 1% JSG showed results similar to the negative control (p = 0.661; p = 0.212, respectively) and the stannous fluoride group (p = 0.103; p = 0.379, respectively). In the SEM images, the specimen treated with stannous fluoride showed obliterated tubules, while the JSG gels formed crystals on the dentin surface, as confirmed by the presence of oxygen and calcium in the EDS analysis. Although the JSG gels showed similar results to the stannous fluoride, did not exhibit superior efficacy at the tested concentrations.

Effects of a commercial whitening toothpaste containing hydrogen peroxide and citric acid on dentin abrasion and erosion

BackgroundHydrogen peroxide (HP) and citric acid (CA), key contributors to toothpaste acidity, can lead to dental loss. This study aimed to compare the amount of abrasion or loss of dentin based on pH, buffering, and concentration of HP and CA in commercial and experimental toothpastes after toothbrushing or immersion.MethodsBovine dentin specimens were randomly assigned to nine solutions. The prepared solutions included two commercial toothpastes (whitening toothpaste [WT] with HP and CA; conventional toothpaste [CT] without HP and CA), reference slurry (RS), two CA solutions (1.92%, CAS1; 0.001%, CAS2), basic solution (7.16% sodium phosphate dibasic [SPDS]), CA phosphate buffer solution (3.58% SPDS and 0.96% CA [CAPB]), HP solution (4%, HPS), and distilled water (DW). Dentin specimens were performed in two treatments: one with only abrasion (10,000 brushings) and one with only immersion (1 h). After treatments, the amount of dentin loss and surface images were measured and observed using noncontact profilometry. Data were analyzed using an one-way analysis of variance and the Tukey test as a post hoc analysis (p < 0.05).ResultsWT with pH 5.0 had lower dentin abrasion than CT and RS after brushing but had higher dentin loss than both after immersion. The dentin surfaces of CAS1, CAPB, and WT were damaged after immersion, whereas HPS, CAS2, CT, SPDS, RS, and DW remained intact after soaking. CAS2 and HPS, which had a pH of 5.0 like WT, did not significantly differ from those of DW after brushing.ConclusionsWT containing HP and CA did not cause significant dentin abrasion but may cause additional dentin loss even without brushing. After brushing or immersion, the CA concentration may affect the dentin surface more than the HP concentration included in WT. The amount of abrasion or loss of dentin after brushing or soaking can vary based on the composition, concentration, and buffer in the solution, even if the pH of the solution is similar to pH 5.0.