Single-rooted Teeth Research Articles

Evaluation of the penetration depth of Guttaflow bioseal and Bioceramic sealers using scanning electron microscope (in vitro study).

Background and objective: Three-dimensional obturation of the canal is mandatory in root canal treatment to decrease failure rate, the major cause of root canal reinfection after obturation is insufficient obturation of the canal which later leads to a periapical lesion and reinfection.This study aimed to evaluate the penetration depth of Guttaflow bioseal and Bioceramic sealer. Methods: Twenty extracted single-rooted human teeth (mandibular first premolar) were used in this study, teeth were decornated leaving 10 mm root length. The chemico-mechanical preparation of the samples was done by using a protaper universal system till size F1 and then samples were divided into 2 groups (n = 10), according to the filling material in the first group Guttaflow bioseal used while in the second group Onefil bioceramic sealer used the sealers introduced into canals according to manufactures instructions and then obturated with gutta-percha size F1, single condensation technique used and finally samples were cross- sectioned at 3 and 7 mm, sealers penetration depth was measured by using scanning electron microscope. Result: Independent sample t-test shows that the difference between the penetration depth of guttaflow bioseal and bioceramic sealers are non-significant while the ANOVA test shows that the difference between the three sections of the root is highly significant for both sealer, coronal section shows the best result for Guttaflow bioseal while middle section for Bioceramic shows the best result of penetration. Conclusion: There are no difference in sealer penetration of both sealers Guttaflow bioseal and Onefil bioceramic, while regarding sealer penetration in each sections of root for Guttaflow bioseal in coronal section shows a best penetration, for Onefil bioceramic middle section shows a best penetration.

Gingival crevicular fluid levels of apelin correlates with clinical periodontal diagnosis.

Limitations of clinical periodontal measurements have led to the search for reliable biomarkers that can be used in diagnosis and monitoring of periodontal diseases. Considering the relationship of adipokines with periodontal disease, diabetes, and obesity, apelin may be a biomarker for periodontal diseases due to its modulating effects on inflammation. The present study was conducted to determine gingival crevicular fluid (GCF) apelin levels in systemically healthy individuals and to evaluate the potential of apelin as a biomarker for periodontal diagnosis. Ten individuals with clinically healthy periodontal tissues, 10 patients diagnosed with gingivitis, and 10 patients with periodontitis were included in the present study. Whole mouth clinical periodontal measurements were recorded and GCF samples were obtained from the buccal approximal regions of single-rooted teeth with features that would represent clinical periodontal diagnosis. Apelin level in the samples was determined by ELISA. Clinical and biochemical findings were statistically analyzed. Possible relationship between the variables was evaluated with Pearson correlation analysis. Apelin level in the gingivitis group was higher than that in the clinically healthy group (p = 0.000) and lower than that in the periodontitis group (p = 0.000). A positive correlation was found between GCF apelin concentration and plaque score, bleeding on probing, and probing depth (p = 0.000). Within the limits of this study, it can be suggested that GCF apelin concentration may be a biomarker that can distinguish between healthy periodontal tissues, gingivitis, and periodontitis patients. Apelin concentration in the gingival crevicular fluid may aid in the diagnosis of periodontal disease.

Mustard Gel is an Effective Intracanal Medicament Against Enterococcus Faecalis: an In-Vitro Study on Extracted Teeth

<p><strong>ABSTRACT</strong></p>
 <p><strong>Background and Objective:</strong> Root canal treatment is hampered by the presence of resilient bacteria within the canals of teeth which leads to the need for incorporation of intra-canal medication. This study aimed to assess the effectiveness of mustard gel against the highly resistant Enterococcus faecalis (E. faecalis) bacteria in comparison with calcium hydroxide (Ca(OH)2) paste as an intra-canal medicament.</p>
 <p><strong>Methods:</strong> This experimental study comprised forty extracted single-rooted teeth which were equally divided into two groups. In group 1, Ca(OH)2 paste was applied whereas in group 2, mustard gel was used. After disinfection, each tooth was sectioned horizontally into three equal parts. The standardized middle section was inoculated with a controlled strain of E. faecalis followed by the application of intra-canal medicaments for a week in both groups. The bacterial colonies were counted as colony-forming units (CFU/ml). Data were entered and analyzed by using Statistical Package for Social Sciences version 25.0.</p>
 <p><strong>Results:</strong> Microscopically, E. faecalis appeared as cocci-round shaped in chains or pairs. The median bacterial count was 1,550 (775-2,500) for group 1 (Ca(OH)2 paste) as compared to only 400 (200-775) in group 2 (mustard gel) (p < 0.001).</p>
 <p><strong>Conclusion:</strong> Mustard gel can be used as a cost-effective, readily available, and safe herbal alternative to Ca(OH)2 paste for root canal treatments.</p>

Effects of immersion in 4-methacryloyloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane resin-activated liquid on microtensile bond strength of root canal dentin

Background/purpose4-methacryloyloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane (4-META/MMA-TBB) resin is used for indirect restorations. We aimed to evaluate effects of immersion in 4-META/MMA-TBB-activated liquid on the bond strength of root canal dentin. Materials and methodsWe used freshly extracted single-rooted human teeth. After decoronation, each root was vertically sectioned into halves; their dentin walls were polished and flattened. The control group underwent dentin treatment with Green Activator. The immersion group was treated with Green Activator and Teeth Primer and immersed in 4-META/MMA-TBB-activated liquid. After bonding the resin blocks with Super-Bond, microtensile bond strength (μTBS) tests were performed (n = 6), and fracture surfaces were analyzed. Before surface treatment, dentin was immersed in a sodium fluorescein solution for 3 h, and resin blocks were bonded with Super-Bond with rhodamine B as in the bond strength test. The bonded cross section was observed using confocal laser scanning microscopy (CLSM). ResultsμTBS was significantly higher in the immersion group than in the control group (61.5 [51.3–66.7] vs. 33.0 [20.4–57.8] MPa; P < 0.05). Fracture mode analysis showed that, compared with the control group, the immersion group had a significantly lower rate of adhesive failure at the dentin interface and a significantly higher rate of cohesive failure in Super-Bond (P < 0.01). CLSM showed a water droplet-like accumulation of fluorescein dye above the hybrid layer in the control group, not in the immersion group. ConclusionImmersion in a 4-META/MMA-TBB-activated liquid inhibited water exudation from the root canal dentin and improved the bond strength.

The results of pulpectomy in primary molars in children with negative behaviour

Relevance. A pulpectomy is a procedure predominantly performed for pulpitis treatment in single-rooted primary teeth. Data on the pulpectomy in primary molars are limited. Pulpectomy in children with negative behaviour is particularly difficult. The study aimed to determine the survival rate of primary molars after treatment of chronic pulpitis by pulpectomy in children with negative behaviour depending on the behaviour management method.Material and methods. A prospective clinical study in parallel groups involved 120 children aged 3-6 years who demonstrated negative behaviour (according to the Frankl scale) during a dental examination. Chronic fibrous pulpitis was treated by vital pulpectomy in 180 primary molars. In group 1 (60 children, 90 teeth), children underwent non-pharmacological behaviour management; in group 2, children were treated under conscious sedation (pharmacological correction of behaviour). Follow-ups after 6, 12, 18 and 24 months determined the tooth survival rate after pulpectomy.Results. The 24-month tooth survival rate after pulpectomy was 76.7% in group 1 (95% CI 67.9-85.4%), 81.1% – in group 2 (95% CI 73.0-89.2%), p &gt; 0.05.Conclusion. More than 75% of primary molars survived for 24 months after vital pulpectomy in children with negative behaviour. The results of pulpectomy with pharmacological behaviour correction were better than after non-pharmacological behaviour management; however, the detected differences were not statistically significant.

Comparative Evaluation of Bacterial Reduction by Laser-Activated Irrigation Technique (LAI) With Conventional Needle Irrigation (CNI) in Single-Rooted Teeth With Pulpal Necrosis: A Single-Blinded Randomized Controlled Trial.

Aim To compare the bacterial reduction in single-rooted teeth with pulpal necrosis after laser-activated irrigation technique(LAI) and conventional needle irrigation (CNI). Methodology In this clinical trial (CTRI/2021/09/047767), 32 patients with pulpal necrosis were enrolled. Under complete aseptic conditions, access cavity preparation was done and the baseline sample S1 was collectedfrom the root canal using paper points. After chemo-mechanical preparation they were allocated into two groups, following block randomization; Group A - CNI with 27 gauge side-vented needle, Group B - LAI with pulsed Er,Cr:YSGG (erbium, chromium:yttrium-scandium-gallium-garnet) (2780 nm) laser. After irrigant activation, canals were dried and a second sample S2 was taken using paper points. Microbial analysis using quantitative polymerase chain reaction (qPCR) was done to quantify the bacterial reduction among the two groups. Inter-group and intra-group analysis was done using the independent student t-test and Bonferroni test, respectively. The data was represented in terms of quantification cycle (Cq) values, which are inversely proportional to the microbial count. Results There was no significant difference in S1 between the two groups (mean difference=0.0205; p=0.912). There was a significant difference in S2 between the two groups for the organisms (mean difference=0.8042; p=0.000). The mean percentage of bacterial reduction in CNI was 10.82% and in LAI it was 25.92%. There was a significant difference in S1 through S2 within the two groups for the organisms (p=0.000). The mean difference of Cq value is high for LAI compared to CNI (1.3494). The fold change was calculated by taking the ΔCq value and ΔΔCq value after the logarithmic transformation of the Cq value. LAI showed lower levels of DNA at S2 similar to CNI. There is no significant difference in mean fold change between CNI and LAI (p=0.564). Conclusion This clinical trial concluded that both LAI and CNI were effective in bacterial reduction. There was greater bacterial reduction with LAI (25.92%) than with the CNI (10.82%) in single-rooted teeth with pulpal necrosis using qPCR analysis.

Accuracy of two electronic apex locators: in vivo and in vitro study

The present study proposed the comparison of the reading between the in vivo and in vitro models during the evaluation of Root ZX II foramen locators and Propex II. The localization of the major foramen was determined electronically in 40 canals of human single-rooted teeth in the in vivoand in vitro models. After the two measurements, the actual tooth length was measured. All values were tabulated and submitted to the statistical analysis of the data, applying the non-parametric Kruskal-Wallis test with significance level of 5% (p&lt;0,05). Statistical analysis revealed no significant differences between the in vivo and in vitro models regarding the accuracy of the Root ZX II and Propex II devices during the localization of the major foramen. In the in vivo model, Propex II presented accuracy of 75% (±0,5mm) and 90% (±1,0mm) and Root ZX II presented accuracy of 80% (±0,5mm) and 92,5% (±1,0mm). For the in vitro model, Propex II presented accuracy of 72,5% (±0,5mm) and 97,5% (±1,0mm) and Root ZX II presented accuracy of 80% (±0,5mm) and 95% (±1,0mm). There were no statistically significant differences between the in vivo and in vitro models and between the devices used in the research.

Influence of Embedding Medium on iPex Electronic Apex Locator Accuracy: An Ex Vivo Comparative Study Using Alginate, Saline, and Gelatin Models.

Accurate working length determination during root canal treatment is essential for achieving successful outcomes. This study aimed to evaluate the impact of embedding medium on the accuracy of iPex electronic apex locator (EAL). Sixty-one extracted single-rooted teeth were decoronated and coronally flared with Gates-Glidden burs. Actual canal length (ACL) was obtained by introducing a size 8 K-file until its tip reached the most coronal border of the apical foramen. This step was performed thrice and then averaged. Deducting 0.5 mm from the ACL provided the working length (WL). The teeth were randomly placed in plastic containers filled with freshly mixed alginate, gelatin, or saline, with the lip clip placed in the medium. The blinded operator obtained electronic measurements using iPex by advancing a K-file with a size compatible with the canal attached to the file clip and advanced until the 0.0 mark, then withdrawn to the 0.5 mark. This step was performed thrice and then averaged. Data were analyzed using ANOVA and Tukey's post hoc test, with significance level set at 5% (α = 0.05). The mean difference between WL and iPex length obtained in the gelatin model was significantly longer than the difference with mean iPex length in alginate (p = 0.005) and in saline (p < 0.001). There was no significant difference between iPex readings obtained in alginate and saline (p = 0.249). The use of freshly mixed alginate or saline for ex vivo assessment of iPex is recommended, whereas the use of gelatin could increase the chances of readings longer than looked for. Identifying the optimum embedding medium for ex vivo testing of EALs permits the comparison and assessment of several factors affecting EALs' precision under standardized conditions. This helps in understanding EAL performance in vivo and in optimizing its clinical utilization.

Comparison of the Fracture Resistance of Root-Canal-Treated Premolars Obturated With Dissimilar Materials: An In Vitro Study.

Introduction The utilization of endodontic sealers is of paramount importance in ensuring the sustained efficacy and resilience of endodontic treatment. The primary objective of the researchwas to appraise and contrast the fracture resistance (FR) of three distinct categories of endodontic sealing materials that are frequently employed in the context of endodontictherapy. Materials and methods This research used an in vitro experimental design.Sixty single-rooted human teeth indicatedfor extraction were utilized according to established protocols. These teeth were then arbitrarily divided into four piles, one for each of the four possible sealants. All specimens were put through a standardized thermal cycling procedure to simulate clinical conditions after the root canals were obturated. The subsequent step involved testing the FR of each group by utilizing a universal testing machine up until failure. Any statistically significant difference in FR among the three sealing materials was identified through appropriate statisticalanalysis. Results Group 1, which utilized a particular sealing material, exhibited the highest mean fracture resistance, measuring at an impressive 1198.33 ± 321.4 Newtons (N). A post hoc analysis was done to see the exact differences between each group and statistically significant differences between Groups 1 and 2 (p<0.05), Groups 1 and 4 (p<0.05), and Groups 3 and 4 (p<0.001) were observed. Conclusion The FR of Group 1 specimens were noticeably greater than those of Group 2 and Group 4while the FR of Group 3 specimens was more than that of the Group 4 specimens. This study provides important insights into the fracture resistance of various endodontic sealing materials.

Effect of photobiomodulation therapy on TGF-β release from dentin, migration and viability of dental pulp stem cells in regenerative endodontics treatment: An ex vivo study

Background and aimRegenerative endodontic procedures (REPs) are oriented by the principles of tissue engineering, incorporating dental pulp stem cells (DPSC), crucial growth factors like Transforming growth factor-β (TGF-β1), and scaffolds to facilitate the regeneration of dental pulp tissues. The present study aimed to investigate the effect of photobiomodulation (PBM) therapy, using an 808 nm diode laser on cellular modulation mechanisms in REPs. Method and materialA total of 108 human dentin discs obtained from intact single root teeth were randomly assigned into six groups (n = 8): 1. Positive control (EDTA), 2. PBM-1 (3 J/cm2), 3. PBM-2 (5 J/cm2), 4. EDTA+PBM-1, 5. EDTA+PBM-2, and 6. Negative control (NaOCl). Then, an extract solution was prepared from each disc and the concentration of released TGF-β1 from the discs was measured using enzyme-linked immunosorbent assay (ELISA). Moreover, the extract solution was added to DPSC culture medium to evaluate cell viability and migration through MTT assay and scratch test, respectively. ResultThe group exposed to PBM-1 showed the highest cell viability, while treatment with EDTA and EDTA+PBM-2 decreased cellular viability. Also, the PBM-treated groups showed significantly higher release of TGF-β1 compared to the negative control. EDTA and EDTA+PBM-1 showed the highest release among all the groups. No significant difference was found between EDTA and EDTA+PBM-1, as well as between PBM-1 and PBM-2. Moreover, the PBM-1 group exhibited the highest migration after 24 h, which was significantly greater than other groups, except for the PBM-2 group. ConclusionAccording to the obtained data, 808 nm mediated-PBM (3 J/cm2), both independently and in conjunction with EDTA, enhanced the release of TGF-β1 from dentin and improved cell viability and migration of DPSCs. It seems that, PBM under the specific parameters employed in this study, could be an effective adjunctive therapy in REPs.

Functional Load Capacity of Teeth with Reduced Periodontal Support: A Finite Element Analysis.

The purpose of this study was to investigate the functional load capacity of the periodontal ligament (PDL) in a full arch maxilla and mandible model using a numerical simulation. The goal was to determine the functional load pattern in multi- and single-rooted teeth with full and reduced periodontal support. CBCT data were used to create 3D models of a maxilla and mandible. The DICOM dataset was used to create a CAD model. For a precise description of the surfaces of each structure (enamel, dentin, cementum, pulp, PDL, gingiva, bone), each tooth was segmented separately, and the biomechanical characteristics were considered. Finite Element Analysis (FEA) software computed the biomechanical behavior of the stepwise increased force of 700 N in the cranial and 350 N in the ventral direction of the muscle approach of the masseter muscle. The periodontal attachment (cementum-PDL-bone contact) was subsequently reduced in 1 mm increments, and the simulation was repeated. Quantitative (pressure, tension, and deformation) and qualitative (color-coded images) data were recorded and descriptively analyzed. The teeth with the highest load capacities were the upper and lower molars (0.4-0.6 MPa), followed by the premolars (0.4-0.5 MPa) and canines (0.3-0.4 MPa) when vertically loaded. Qualitative data showed that the areas with the highest stress in the PDL were single-rooted teeth in the cervical and apical area and molars in the cervical and apical area in addition to the furcation roof. In both single- and multi-rooted teeth, the gradual reduction in bone levels caused an increase in the load on the remaining PDL. Cervical and apical areas, as well as the furcation roof, are the zones with the highest functional stress. The greater the bone loss, the higher the mechanical load on the residual periodontal supporting structures.

MicroRNAs in Gingival Crevicular Fluid: An Observational Case-Control Study of Differential Expression in Periodontitis.

microRNAs (miRNAs) present in the gingival crevicular fluid (GCF) of patients with chronic periodontitis may serve as biomarkers of periodontal disease. The aim of this study was to perform a miRNA-sequencing study of all miRNAs present in GCF, comparing miRNA expression level profiles between advanced chronic periodontitis (CP) patients and healthy subjects (HS). GCF samples were collected from the single-rooted teeth of patients with severe CP (n = 11) and of HS (n = 12). miRNAs were isolated from GCF using an miRNeasy Serum/Plasma kit(Qiagen GmbH, Hilden, Germany). Reverse transcription polymerase chain reaction (qRT-PCR) was used to determine the expression levels of miRNA candidates involved in periodontal pathogenesis. Of all the sequenced miRNAs, miR-199, miR-146a, miR-30a, and miR-338 were identified as best representing the CP patient samples. The validation study identified miR-199 as the most powerful biomarker used to define periodontitis. Upon sequencing all known miRNAs in GCF for the first time, we uncovered several potential biomarkers to define periodontitis. Identifying miRNAS in the GCF using high-throughput approaches will clarify the role of these molecules in periodontitis and provide biomarkers with potential applications.

Analysis of the achievement of primary and secondary goals and influencing factors in single-rooted immature permanent teeth after regenerative endodontic procedures: a retrospective study

ObjectiveThis study explored the achievement of primary and secondary goals and factors influencing their achievement in regenerative endodontic procedures (REPs) for immature permanent teeth.MethodsDental records of all patients who received REPs for immature permanent teeth at the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology between January 2012 and January 2023 were retrieved. The evaluation of the primary goal was based on medical and radiographic records. The achievement of the primary goal was defined as the absence of clinical signs and symptoms, such as pain, swelling, or sinus tract and the absence of periapical radiolucency, as assessed on postoperative periapical radiographs. The achievement of secondary goal represented increased root wall thickness and/or increased root length, that is, continued root development. Periapical radiographs before and after treatment were used to evaluate the achievement of the secondary goal. The secondary goal was required to be achieved alongside the achievement of primary goal.ResultsA total of 436 teeth (136 anterior and 300 posterior teeth) were included in this study, 96.1% of which demonstrated achievement of the primary goal. Signs of failure (17 teeth) included crown fracture and uncontrolled and recurrent periapical lesions. In addition, 77.8% of teeth demonstrated achievement of the secondary goal, and more than half of the teeth exhibited a complete root development. Evaluation factors included patients’ age, sex, tooth type, etiology, preoperative periapical lesion, duration of clinical signs and symptoms, follow-up period, and stage of root development. The achievement of the primary and secondary goals were significantly related to age and tooth type (p < 0.05).ConclusionsChildren with a younger initial visit age are more likely to achieve primary and secondary goals. Additionally, posterior teeth had an advantage over anterior teeth in achieving primary and secondary goals.

Comparison of histologic and radiographic changes of sockets grafted with LPRF and sockets without intervention after tooth extraction.

After tooth extraction, marked resorption occurs in extraction socket walls, leading to functional and esthetic problems in that area. One of the methods introduced to reduce this resorption is the use of platelet derivatives. This study aimed to evaluate the effects of leukocyte and platelet-rich fibrin (L-PRF) on the changes following tooth extraction. The participants were 24 patients who needed to replace at least one single-rooted tooth with an implant. They were randomly divided into test and control groups. After the tooth extraction, the sockets in the test group received LPRF clots, while in the control group, the sockets were left free of any interventions. CBCT scans were obtained from the extraction site both immediately after the tooth extraction and 8 weeks later. The histologic biopsy was also obtained while the implant site was being prepared 8 weeks after the extraction. The average vertical bone loss in the buccal crest was not significantly different between the two groups (1.67 ± 1.67 in the test group and 2.3 ± 1.36 in the control group; mean difference = - 0.36, 95% CI: - 1.65-0.93, p-value = 0.57). Nor was the difference in resorption of the palatal wall (mean difference = - 0.19, 95% CI: - 1.51.12, p-value = 0.76). The mean ridge width resorption in 25% of the coronal aspect of sockets was also measured in the test (1.30 ± 0.66) and control group (0.58 ± 0.95) (mean difference = 0.73, 95% CI: 0.03-1.42, p-value = 0.04). The new bone formation in histologic view was not statistically different between groups (p-value = 0.15). The LPRF neither reduces the rate of ridge resorption in vertical or horizontal dimensions of extraction sockets nor induces more new bone formation. This study helps dentists choose the appropriate material for ridge preservation.

Assessment of the Penetration of an Endodontic Sealer into Dentinal Tubules with Three Different Compaction Techniques Using Confocal Laser Scanning Microscopy.

Adequate root canal sealing is essential for the success of endodontic treatment. There are numerous techniques available; identifying simple and efficient techniques is important to provide good patient care. The purpose of the study was to compare the maximum penetration depth and the percentage of sealant penetration of an endodontic sealer into dentine tubules using cold lateral condensation, continuous wave, and hybrid techniques, and to contrast the effectiveness of two different tapered gutta-percha master cones (0.02 and 0.04). A sample of sixty single root teeth was used. Six experimental groups were formed from the three filling techniques and the two tapered master cones. Images were acquired using a confocal laser scanning microscope. In the apical root third, the penetration percentage was higher in the hybrid compared with the continuous wave technique. The results indicated a higher penetration depth of hybrid compared with cold lateral condensation in the middle and coronal thirds, and in the apical third, a higher penetration was identified in the hybrid group compared with the continuous wave group. No significant differences in penetration were found comparing 0.02 with 0.04 taper gutta-percha groups. The coronal cross-sections presented a higher penetration than the apical third sections. In conclusion, the hybrid technique a had higher maximum sealer penetration than the continuous wave in the apical third, and the coronal third hybrid and continuous wave had a higher penetration than cold lateral condensation.

Root canal filling quality and bond strength of endodontic sealers to human and bovine dentin

Objective: This study aimed to compare the filling quality and bond strength of two endodontic sealers, AH Plus and Bio-C Sealer, in human and bovine teeth. Methods: The root canals of 60 [30 human (H) and 30 bovine (B)] single-rooted teeth were prepared and filled by lateral condensation of gutta-percha and AH Plus (groups AP-H and AP-B) or Bio-C Sealer (groups BC-H and BC-B). Six 1.5-mm-thick slices were obtained from each root. The specimens were observed under a stereomicroscope to assess filling quality, considering possible voids within the filling material. Subsequently, root slices were evaluated in terms of push-out bond strength and failure mode. Data were analyzed by Mann-Whitney tests and Spearman correlation coefficients (α=5%). Results: The filling quality provided by AP and BC was similar in both dentin substrates. However, when comparing human and bovine teeth, void scores were greater in the bovine samples, for both sealers. AP had higher bond strength to human and bovine dentin than BC. However, there was no significant difference in bond strength between dentin substrates, for both sealers tested. Also, there was a positive and moderate correlation between the bond strength values of human and bovine teeth. The mixed failure mode was the most prevalent. Conclusion: AP and BC provide similar filling quality, but the first presents higher bond strength values to human and bovine dentin. The use of bovine teeth as substitutes for human samples seems adequate in studies related to bond strength, but not in those testing root canal filling quality.&#x0D; Keywords: Dentin, Endodontics, Root canal filling materials.

A Comparative Evaluation of Pulp Tissue Dissolving Ability of Three Different Pulp Dissolving Agents With 5.25% Sodium Hypochlorite: An In-Vitro Study

Introduction: The dissolution of pulp tissue is an essential aspect of root canal treatment, as it aids in the removal of necrotic or infected tissue from the root canal, thereby reducing the microbial load. Aim: This in-vitro study aimed to compare the pulp tissue dissolving ability of three different pulp-dissolving agents with a 5.25% sodium hypochlorite (NaOCl) solution. Materials and Methods: 128 intact, non-carious extracted human single-rooted premolar teeth were selected and sectioned to harvest intact pulp tissue. Pulp tissue samples were randomly divided into four experimental groups (n=32) based on the pulp dissolving agent used: Group I (5.25% NaOCl solution), Group (5% Calcium hypochlorite solution), Group III (5.25% NaOCl gel) and Group IV (8% Papain gel). The initial weight of each sample was recorded and samples were exposed to specific pulp-dissolving agents for specified time intervals. The time required for complete dissolution of the pulp tissue was recorded for all samples till 120 mins. Results: The study analyzed the mean weight of pulp tissue in various groups, including Group I, Group II, Group III, and Group IV. After 30 minutes, complete dissolution of pulp tissue was evident in Group I, while Group II showed 0.0058 grams of remaining tissue after 30 minutes, 0.0040 grams after 60 minutes, and 0.0022 grams after 120 minutes. Group III showed 0.0072 grams of remaining tissue after 30 minutes, and Group IV showed 0.0075 grams of remaining tissue after 30 minutes, 60 minutes, 90 minutes, and 120 minutes. Conclusion: 5.25% NaOCl has the highest pulp tissue dissolution efficacy compared to other dissolving agents. Further clinical studies are warranted to validate these findings and assess the feasibility of these agents in clinical practice.

Bacteria debridement efficacy of two sonic root canal irrigant activation systems

ObjectiveTo evaluate the bacteria debridement efficacy of two generations of sonic root canal irrigant activation systems: EndoActivator (Dentsply Sirona), the first generation, and SmartLite Pro EndoActivator, the second generation. MethodsInstrumented, autoclaved, single-rooted human premolars were inoculated with Enterococcus faecalis (ATCC-29212) for 21 days. The bacteria biofilm-containing teeth were randomly divided into 5 groups (N=8): Group 1: Syringe-side-vented needle (S-N) delivery of saline for 1 min; Group 2: S-N delivery of 2% NaOCl for 1 min; Group 3: S-N delivery of 2% NaOCl for 5 min; Group 4: EndoActivator activation of 2% NaOCl for 1 min; Group 5: SmartLite Pro EndoActivator activation of 2% NaOCl for 1 min. The teeth were evaluated for bacterial reduction using CFU counts, and the percentages of dead bacteria within the dentinal tubules using confocal laser scanning microscopy. ResultsActivation of NaOCl with EndoActivator or SmartLite Pro EndoActivator significantly reduced the overall intracanal bacterial load, compared with S-N irrigant delivery (P<0.05), with no significant difference between the two agitation devices (P>0.05). Nevertheless, S-N delivery of 2% NaOCl for 5 min produced better bacteria debridement than either sonic agitation system. Different degrees of bacteria kill were identified in the coronal-middle portions and apical portion of the canal space. ConclusionDelivery time of NaOCl affects the efficacy of bacteria disinfection. Activation for 1 min with the EndoActivator or SmartLite Pro EndoActivator demonstrated comparable canal wall biofilm and intracanal bacteria reduction efficacy when 2% NaOCl was used as irrigant for disinfecting E. faecalis in single-rooted teeth. Clinical significanceAlthough the sonic root canal irrigant activation devices investigated do not completely eliminate live bacteria biofilms from the canal space, they help reduce bacteria load during irrigant activation.

Suppression of subgingival bacteria by antimicrobial photodynamic therapy using transgingival irradiation: A randomized clinical trial.

Antimicrobial photodynamic therapy (aPDT) is an effective method for eradicating bacteria in periodontal therapy. Standard aPDT requires the insertion of a laser tip into a periodontal pocket, in which the direction of irradiation is limited. Therefore, we devised an aPDT method that uses a transgingival near-infrared wavelength and indocyanine green-encapsulated and chitosan-coated nanoparticles as a photosensitizer. Forty patients undergoing supportive periodontal therapy, who had a single root tooth with a pocket of 5mm or deeper, were used as subjects. In the test group, aPDT was performed by laser irradiation from outside the gingiva using photosensitizer nanoparticles. In the control group, pseudo aPDT without photosensitizer was performed by transgingival irradiation. Subgingival plaque was sampled from inside the pocket before, immediately after, and 1 week after treatment, and evaluated by colony counting and real-time polymerase chain reaction. There were no significant differences in age, sex, periodontal pocket depth, and bleeding on probing between the test and control groups. Compared with the colony count before treatment, the count in the test group was significantly reduced immediately after treatment. The number of patients with colony reduction to ≤50% and ≤10% was significantly higher in the test group than in the control group. None of the participants reported pain, although one participant reported discomfort. As a bacterial control method for residual pockets in patients undergoing supportive periodontal therapy, transgingival aPDT is a promising treatment strategy that is not generally accompanied by pain or discomfort.

Assessing the effect of piezoelectric ultrasonic scaler tip wear on root surface roughness under influence of various working parameters: A profilometric and atomic force microscopic study.

Assessing the effect of scaler tip wear on the root surface roughness using piezoelectric ultrasonic scaling device under influence of various working parameters, i.e. power setting, lateral force, and instrumentation time. An experimental study was conducted using 160 single-rooted tooth samples divided into two groups of new (n = 80) and worn tips (n = 80). Samples were prepared to examine the root surface roughness after being instrumented by new and worn piezoelectric ultrasonic tips (8 new/8 worn) at different parameters. The erosion ratio (ER) of the new/worn tip was examined under an atomic force microscope and roughness over root surface was measured by a contact surface profilometer. One-way analysis of variance test, post hoc Tukey's test, and independent t-test were used for intragroup, pair-wise multiple comparisons and intergroup comparison of average roughness (Ra) value. A statistically significant difference was found between the ER of new and worn scaler tips (P < 0.001). Intragroup comparison between subgroups 1 and 8 showed a higher Ra value in both the groups (P < 0.005). There was a significantly higher Ra value of worn tips compared to new tips (P < 0.05). Significantly higher mean Ra value was shown when lateral force changed from 50 g to 100 g (P < 0.005). Increasing value of power setting, lateral force, and instrumentation time caused more surface roughness in worn-out scaler tips compared to new scaler tips. Lateral force and instrumentation time proved to be a major factor influencing surface roughness.