This study aimed to evaluate carbonated hydroxyapatite (CHA)’s ability for mineral induction and its in vitro cytotoxicity with human dental pulp cells.

Precursors for the study include di-ammonium hydrogen phosphate and calcium nitrate tetrahydrate, with sodium hydrogen carbonate added to achieve different levels of carbonate substitution. The synthesized CHA samples are characterized using X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Scanning electron microscopy (SEM) was used to observe morphology. For 14 days at 37°C, samples were submerged in simulated body fluid to assess their mineral induction capabilities. SEM was used to confirm apatite formation on sample surfaces. The cytotoxicity assay was used to assess the vitality of the cells following their exposure to various concentrations of CHA.

The Joint Committee on Powder Diffraction Standards data for HA aligned well with the results from X-ray diffraction analysis of CHA across 3 different concentrations, indicating strong agreement. Fourier transform infrared spectra indicated the presence of phosphate, hydroxyl, and carbonate groups within the samples. SEM and Energy-dispersive X-ray analysis show agglomerated and flaky nanoparticles. All the samples are bioactive, but the formation of apatite differs from one another. In vitro cytotoxicity assay showed that over 70% of cells maintain viability.

The results of this study may provide insight into the potential use of carbonated HA as a dental pulp-capping material for vital pulp therapy.

This study aimed to evaluate the physical-mechanical, chemical, and biological properties of graphene-reinforced glass ionomer cements (GICs).

Different proportions of graphene powder were incorporated into 2 high-viscosity self-curing GIC, Ketac Molar (G_Ketac) and Fuji IX (G_Fuji), in 4 different concentrations: 0.5%, 1%, 2%, and 5%. The control groups included the GICs without graphene. Experiments were performed to analyze linear (Ra) and volumetric roughness (Sa), antimicrobial activity, radiopacity, fluoride release, microhardness, solubility, and water sorption. Data were analyzed using Kruskal-Wallis, Mann-Whitney, Wilcoxon, analysis of variance, and Tukey’s test (p ≤ 0.05).

The G_Ketac 0% and G_Fuji0% groups presented higher Ra (4.05 and 2.72) and Sa (4.76 and 5.16), respectively. No inhibition zone was observed, and the incorporation of graphene reduced radiopacity. Moreover, there was no influence on the solubility and water sorption after 21 days. A greater fluoride release was observed in the period of 7 days for most of the groups. After 21 days, G_Ketac 5%, 2%, and 1% presented higher releasing than 0% and 0.5% (p ≤ 0.05).

The graphene incorporation improved the microhardness of GICs in lower concentrations. Graphene incorporation to GICs modified some physical-mechanical, and chemical, but not affected biological properties.

The aim of this study was to compare the effects of different polymerization strategies and the effectiveness of finishing and polishing procedures of composite resins on color stability.

The samples were divided into 4 main groups according to the polymerization strategy, and all groups except the control group received surface treatment. Each group was subsequently divided into 3 subgroups respectively: Kuraray Clearfil Majesty ES-2 Classic, Premium and Universal. Approximately 24 hours after preparation of the samples, they were immersed for 7 days in a coffee solution. A first color measurement was performed after the preparation of the samples, the second measurement was performed after 7 days in the coffee solution. All measurements were carried out using a dental spectrophotometer to assess the CIE L* a* b* color parameters.

There was a statistically significant difference between ΔE values for different procedures (p = 0.003); in particular, the differences were found only between the groups that received surface treatment and the control group. In addition, a statistically significant difference was observed between the values of ΔE for different composites in the different procedure groups.

Spectrophotometric analysis showed that the additional photopolymerization and oxygen inhibition procedures did not yield better results in relation to color stability. In addition, finishing and polishing provided better color stability compared to not performing these procedures.

The aim of the current study was to evaluate the effect of polishing systems and surface sealant on the color stability and whiteness index of single-shade resin composites after staining and bleaching.

Three single-shade (Omnichroma, Charisma Diamond One, Zenchroma) and one multi-shade (Filtek Z250) materials were tested. From each resin composite, 40 specimens were prepared. The specimens were divided into 4 subgroups (n = 10) according to the surface treatments: 1-step polishing, 1-step + Biscover LV, 2-step polishing, and 2-step polishing + Biscover LV. Color differences (ΔE₀₀) were calculated after being immersed in the coffee solution for 12 days. After the staining, the specimens were immersed in a whitening mouthrinse (Crest-3D White) for 12 hours. Whiteness index differences (∆WI_D = WI_D after staining − WI_D after bleaching) values were recorded. The generalized linear model was used for analysis (p < 0.05).

The lowest and highest ΔE₀₀ values were found for Zenchroma and Charisma Diamond One respectively. Sealed groups indicated higher ΔE₀₀ values than nonsealed groups with significant differences (p = 0.008). The lowest and highest ΔWI_D values were found for Zenchroma and Charisma Diamond One respectively. Sealed groups indicated lower ΔWI_D values than nonsealed groups with significant differences (p = 0.022).

The use of surface sealant increased the discoloration and showed less whiteness change in resin materials. When the 1-step was compared with the 2-step polishing, the effects on the color stability and whiteness index values of the resin materials were similar.

This study aimed to investigate the endodontic characteristics of mandibular premolars with dens evaginatus (DE) that require endodontic treatment.

Patients who underwent endodontic treatment were enrolled. The inclusion criteria were patients who underwent root canal treatment in the lower permanent teeth with DE and were followed up for at least 1 year. Preoperative clinical and radiographic variables were obtained. The frequency distribution of the preoperative variables was compared using the χ² or Fisher’s exact tests. The significance of the change in periapical health index (PAI) and root development stages before and after treatment was examined using the Wilcoxon signed-rank test.

A total of 150 teeth of 134 patients with an average age of 15.3 years were included. The percentage distribution comparison of the preoperative variables and obturation techniques revealed significant differences in pulpal and periapical diagnosis, and percussion, and especially regarding age, root development stage, and PAI. Age was the only statistically significant preoperative variable associated with root growth (p < 0.05).

Approximately, 60% of DEs requiring endodontic treatment had immature roots. Age being the most significant predisposing factor, early treatment provides the greatest opportunity for full root development.

This study aimed to evaluate the clinical performance of an alkasite restorative material in molars that had undergone root canal treatment.

The research was registered in Brazilian Registry of Clinical Trials. The randomized clinical trial involved 33 patients, each with at least 1 mandibular molar requiring restoration after receiving endodontic treatment. Patients were randomly assigned to receive either bulk-fill resin composite (Tetric N Ceram Bulk Fill, Ivoclar Vivadent) or the alkasite restorative material (Cention N, Ivoclar Vivadent). Upon completion of the restorations, 3 calibrated professionals utilized the United States Public Health Service criteria to assess various factors, including retention, secondary caries, marginal adaptation, restoration color, marginal pigmentation, and anatomical form. Evaluations were conducted at intervals of 7 days, 6 months, and 17 months. Additionally, the assessment encompassed the presence of radiolucent lines adjacent to the restoration, material deficiencies or excess, contact points, and caries recurrence. The data underwent analysis using the Friedman and Mann-Whitney tests (α = 0.05).

After 17 months, the results revealed that the alkasite restorative material exhibited greater wear of anatomical shape compared to the bulk-fill resin composite (p = 0.0189). Furthermore, the alkasite restorative material significantly differed from the natural tooth color in most cases (p = 0.0000). However, no other criteria displayed significant differences between the materials or over time (p > 0.05).

The alkasite restorative material (Cention N) emerges as a viable option for restoring endodontically treated teeth, displaying clinically acceptable alterations after a 17-month evaluation period.

Brazilian Registry of Clinical Trials (ReBEC) Identifier: RBR-97kx5jv

This study aimed to establish a single-session associative protocol for non-restorative management of dentin hypersensitivity (DH).

Twenty-four individuals with DH and a minimum sensitivity level of 4 on the visual analog scale (VAS) were selected. The study was conducted in a split-mouth design, with each participant (n = 20) having at least 1 affected tooth in all quadrants. The management protocols consisted of control group: universal adhesive, Neural Desensitizing Protocol group: 5% potassium nitrate, Mixed Desensitizing Protocol (PAM) group: 5% sodium fluoride and 5% potassium nitrate, Remineralizing Desensitizing Protocol (PDR) group: surface-partially reacted glass technology photopolymerizable varnish. Evaluations were performed immediately after application, at 1 week, 1 month, 2 months, and 12 months using the VAS sensitivity test.

The scores were subjected to statistical analysis using the Friedman test (p < 0.05), Durbin-Conover test (p < 0.05), and Wilcoxon test (p < 0.05). At the 12-month evaluation, all groups showed statistically significant differences compared to the initial assessment. For the evaluation after 12 months, there was a statistically significant difference between the PAM group, the control group, and the PDR group.

It can be concluded that all groups were effective in controlling DH, but there were significant results in the control group and PDR group. The clinical relevance of this study is to demonstrate that the application of single-session desensitizing protocols can be effective in controlling DH for up to 12 months.

Brazilian Clinical Trials Registry Identifier: RBR-4r63d7s

This study aimed to evaluate the content, quality and demographics of YouTube videos about rubber dam as an information source for clinicians and dental students.

“Rubber dam,” “rubber dam application,” “dental isolation,” “rubber dam isolation,” and “dental dam” were determined as keywords for the detection of YouTube videos related to rubber dam. Seventy 3 videos were evaluated and a total of 34 videos met the inclusion criteria. All selected videos were evaluated according to 8 parameters. The videos were scored 1 if the videos contained information about the selected parameter, but if the videos did not contain enough information, they were scored 0. The data were statistically analyzed with the analysis of variance and post hoc Tukey test (p < 0.05).

We found that 41% of the videos have poor, 47% have moderate, and 12% have good information. There is a statistically significant difference in time between poor and good information content (p < 0.05). There is a statistically significant difference between the poor and good information in the video information and quality index 1.

Rubber dam-related videos available on YouTube are generally moderately informed and insufficient. YouTube is currently not sufficient as a source of information for patients and clinicians at the moment. The YouTube platform should be developed and enriched with quality information on current and dental issues.

The purpose of this study was to evaluate the effect of Dental Practicality Index (DPI) training using an online video on the treatment planning decisions and confidence level of dental undergraduates (DUs).

Ninety-four DUs were shown 15 clinical case scenarios and asked to decide on treatment plans based on 4 treatment options. The most appropriate treatment plan had been decided by a consensus panel of experienced dentists. DUs then underwent DPI training using an online video. In a post-DPI-training test, DUs were shown the same clinical case scenarios and asked to assign the best treatment option. After 6 weeks, DUs were retested to assess their knowledge retention. In all 3 tests, DUs completed the confidence level scale questionnaire. Data were analyzed using the related-samples Wilcoxon signed rank test and the independent-samples Mann-Whitney U test with the level of significance set at p < 0.05.

DPI training significantly improved the mean scores of the DUs from 7.53 in the pre-DPI-training test to 9.01 in the post-DPI-training test (p < 0.001). After 6 weeks, the mean scores decreased marginally to 8.87 in the retention test (p = 0.563). DPI training increased their confidence level from 5.68 pre-DPI training to 7.09 post-DPI training.

Training DUs using DPI with an online video improved their decision-making and confidence level in treatment planning.

This study aimed to evaluate the impact of substrate color and interface distance on the color adjustment of 2 single-shade composites, Vittra APS Unique and Charisma Diamond One.

Dual disc-shaped specimens were created using Vittra APS Unique or Charisma Diamond One as the center composite, surrounded by shaded composites (A1 or A3). Color measurements were taken with a spectrophotometer against a gray background, recording the color coordinates in the CIELAB color space. Illumination with a light-correcting device and image acquisition using a polarizing filter-equipped cell phone were performed on specimens over the same background. Image processing software was used to measure the color coordinates in the center and periphery of the inner composite and in the outer composite. The color data were then converted to CIELAB coordinates and adjusted using data from the spectrophotometer. Color differences (ΔE₀₀) between the center/periphery of single-shade and outer composites were calculated, along with color changes in single-shade composites caused by different outer composites. Color differences for the inner composites surrounded by A1 and A3 were also calculated. Data were analyzed using repeated-measures analysis of variance (α = 0.05).

The results showed that color discrepancies were lowest near the interface and when the outer composite was whiter (A1). Additionally, Charisma Diamond One exhibited better color adjustment ability than Vittra APS Unique.

Color discrepancies between the investigated single-shade composites diminished towards the interface with the surrounding composite, particularly when the latter exhibited a lighter shade.

This study aims to correlate caries-causing microorganism load, lactic acid estimation, and blood groups to high caries risk in diabetic and non-diabetic individuals and low caries risk in healthy individuals.

This study includes 30 participants divided into 3 groups: Group A, High-risk caries diabetic individuals; Group B, High-risk caries non-diabetic individuals; and Group C, Low-risk caries individuals. The medical condition, oral hygiene, and caries risk assessment (American Dental Association classification and International Caries Detection and Assessment System scoring) were documented. Each individual’s 3 mL of saliva was analyzed for microbial load and lactic acid as follows: Part I: 2 mL for microbial quantity estimation using nutrient agar and blood agar medium, biochemical investigation, and carbohydrate fermentation tests; Part II: 0.5 mL for lactic acid estimation using spectrophotometric analysis. Among the selected individuals, blood group correlation was assessed. The χ² test, Kruskal-Wallis test, and post hoc analysis were done using Dunn’s test (p < 0.05).

Group A had the highest microbial load and lactic acid concentration, followed by Groups B and C. The predominant bacteria were Lactobacilli (63.00 ± 15.49) and Streptococcus mutans (76.00 ± 13.90) in saliva. Blood Group B is prevalent in diabetic and non-diabetic high-risk caries patients but statistically insignificant.

Diabetic individuals are more susceptible to dental caries due to high microbial loads and increased lactic acid production. These factors also lower the executing tendency of neutrophils, which accelerates microbial accumulation and increases the risk of caries in diabetic individuals.

This study aimed to investigate the effectiveness of different topical/systemic agents in reducing the damage caused by bleaching gel to pulp tissue or cells.

Electronic searches were performed in July 2023. In vivo and in vitro studies evaluating the effects of different topical or systemic agents on pulp inflammation or cytotoxicity after exposure to bleaching agents were included. The risk of bias was assessed.

Out of 1,112 articles, 27 were included. Nine animal studies evaluated remineralizing/anti-inflammatories agents in rat molars subjected to bleaching with 35%–38% hydrogen peroxide (HP). Five of these studies demonstrated a significant reduction in inflammation caused by HP when combined with bioglass or MI Paste Plus (GC America), or following KF-desensitizing or Otosporin treatment (n = 3). However, orally administered drugs did not reduce pulp inflammation (n = 4). Cytotoxicity (n = 17) was primarily assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on human dental pulp cells and mouse dental papilla Cell-23 cells. Certain substances, including sodium ascorbate, butein, manganese chloride, and peroxidase, were found to reduce cytotoxicity, particularly when applied prior to bleaching. The risk of bias was high in animal studies and low in laboratory studies.

Few in vivo studies have evaluated agents to reduce the damage caused by bleaching gel to pulp tissue. Within the limitations of these studies, it was found that topical agents were effective in reducing pulp inflammation in animals and cytotoxicity. Further analyses with human pulp are required to substantiate these findings.

PROSPERO Identifier: CRD42022337192

This study aimed to evaluate the bleaching efficacy and hydrogen peroxide permeability in the pulp chamber by the at-home bleaching gel in protocols applied on different dental surfaces.

Forty premolars were randomly into 4 groups: control group no bleaching, only application on the buccal surface (OB), only application on the lingual surface (OL) and application in buccal and lingual surfaces, simultaneously (BL). At-home bleaching gel (White Class 7.5%) was used for the procedure. The bleaching efficacy was evaluated with a digital spectrophotometer (color change in CIELAB [ΔE _ab] and CIEDE 2000 [ΔE ₀₀] systems and Whitening Index for Dentistry [ΔWI_D]). The hydrogen peroxide permeability in the pulp chamber (µg/mL) was assessed using UV-Vis spectrophotometry and data were analyzed for a 1-way analysis of variance and Tukey’s test (α = 0.05).

All groups submitted to bleaching procedure showed bleaching efficacy when measured with ΔE _ab and ΔE ₀₀ (p > 0.05). Therefore, when analyzed by ΔWI_D, a higher bleaching efficacy were observed for the application on the groups OB and BL (p = 0.00003). Similar hydrogen peroxide permeability was found in the pulp chambers of the teeth undergoing different protocols (p > 0.05).

The application of bleaching gel exclusively on the OB is sufficient to achieve bleaching efficacy, when compared to BL. Although the OL protocol demonstrated lower bleaching efficacy based on the ΔWI_D values, it may still be of interest and relevant in certain clinical scenarios based on individual needs, requiring clinical trials to better understand its specificities.

This retrospective cohort study examined the incidence of interappointment emergencies during multiple-visit molar root canal treatments conducted by undergraduate students. Treatments performed without the use of intracanal medicament were compared to treatments that incorporated calcium hydroxide as an intracanal medicament.

Interappointment emergencies, defined as instances of pain or swelling that required the patient to make an unscheduled follow-up visit, were recorded for up to 2 months after the intervention. To avoid the influence of obturation on the observed incidence of emergency visits, only unscheduled visits occurring between the start and end of the root canal treatment were included.

Of the 719 patients included in this study, 77 (10.7%) were recorded as experiencing interappointment emergencies. Of these emergencies, 62% occurred within 2 weeks following the most recent intervention. In the group of patients who did not receive intracanal medicament, the incidence of interappointment emergencies was 11.9% (46 of 385 patients). In comparison, this rate was 9.3% (31 of 334 patients) among those who received calcium hydroxide as an intracanal medicament (odds ratio, 1.33; 95% confidence interval, 0.82–2.15; p = 0.249).

Interappointment emergencies may arise at any point during root canal treatment, but they most commonly occur within the first 2 weeks following intervention. The omission of intracanal medicament in multiple-visit molar root canal treatments, performed by undergraduate students, did not significantly increase the incidence of these emergencies.

This study was conducted to evaluate and compare the tip and taper compatibility of accessory gutta-percha points (AGPs) with various rotary and reciprocating instruments.

Using a profile analyzer, tip and taper measurements were taken of 10 AGPs of each of the 14 models available from Odous de Deus and the 4 models available from Dentsply-Maillefer. Diameter measurements were taken at 1-mm intervals, from 3 mm from the tip (D3) to 16 mm.

Based on the mean values obtained, 3-dimensional (3D) models of the AGPs were drawn in Autodesk Fusion 360 and superimposed on 3D models of each instrument selected (Mtwo, Reciproc, RaCe, K3, and ProDesign Logic) to determine the compatibility between the instrument and the AGP. Data corresponding to the tips and tapers of the various AGPs, as well as the tip and taper differences between the AGPs and the instruments, were analyzed using descriptive statistics. The tapers of the AGPs were subject to the American National Standards Institute/American Dental Association No. 57 standard. The Odous de Deus extra-long medium and extra-long extra-medium AGPs were shown to be compatible with Mtwo, K3, and ProDesign Logic instruments with taper 0.06 and tip sizes 25 and 30, while the Dentsply fine and fine medium cones were compatible with Mtwo, RaCe, and K3 instruments with conicity of 0.04 and tip sizes 35 and 40.

Both the Odous de Deus and Dentsply commercial brands included 2 AGP models with tip (D3) and taper compatibility with Mtwo, RaCe, K3, and/or Prodesign Logic instruments.

This study aimed to determine whether collagen triple helix repeat containing-1 (CTHRC1), which is involved in vascular remodeling and bone formation, can stimulate odontogenic differentiation and angiogenesis when administered to human dental pulp stem cells (hDPSCs).

The viability of hDPSCs upon exposure to CTHRC1 was assessed with the WST-1 assay. CTHRC1 doses of 5, 10, and 20 µg/mL were administered to hDPSCs. Reverse-transcription polymerase reaction was used to detect dentin sialophosphoprotein, dentin matrix protein 1, vascular endothelial growth factor, and fibroblast growth factor 2. The formation of mineralization nodules was evaluated using Alizarin red. A scratch wound assay was conducted to evaluate the effect of CTHRC1 on cell migration. Data were analyzed using 1-way analysis of variance followed by the Tukey post hoc test. The threshold for statistical significance was set at p < 0.05.

CTHRC1 doses of 5, 10, and 20 µg/mL had no significant effect on the viability of hDPSCs. Mineralized nodules were formed and odontogenic markers were upregulated, indicating that CTHRC1 promoted odontogenic differentiation. Scratch wound assays demonstrated that CTHRC1 significantly enhanced the migration of hDPSCs.

CTHRC1 promoted odontogenic differentiation and mineralization in hDPSCs.

This study aimed to evaluate the surrounding and underlying shades’ effect on the color adjustment potential (CAP) of a single-shade composite used in a thin layer.

Cylinder specimens (1.0 mm thick) were built with the Vittra APS Unique composite, surrounded (dual specimens) or not (simple specimens) by a control composite (shade A1, A2, or A3). Simple specimens were also built only with the control composites. Each specimen’s color was measured against white and black backgrounds or the simple control specimens with a spectrophotometer (CIELAB system). The whiteness index for dentistry (WI_D) and translucency parameters (TP₀₀) were calculated for simple specimens. Differences (ΔE₀₀) in color between the simple/dual specimens and the controls were calculated. The CAP was calculated based on the ratios between data from simple and dual specimens.

The Vittra APS Unique composite showed higher WI_D and TP₀₀ values than the controls. The highest values of ΔE₀₀ were observed among simple specimens. The color measurements of Vittra APS Unique (simple or dual) against the control specimens presented the lowest color differences. Only surrounding the single-shade composite with a shaded composite barely impacted the ΔE₀₀. The highest CAP values were obtained using a shaded composite under simple or dual specimens.

The CAP of Vittra APS Unique was strongly affected by the underlying shade, while surrounding this composite with a shaded one barely affected its color adjustment.

This study aimed to compare the torsional and cyclic fatigue resistance of ProGlider (PG), WaveOne Gold Glider (WGG), and TruNatomy Glider (TNG).

A total of 15 instruments of each glide path system (n = 15) were used for each test. A custom-made device simulating an angle of 90° and a radius of 5 millimeters was used to assess cyclic fatigue resistance, with calculation of number of cycles to failure. Torsional fatigue resistance was assessed by maximum torque and angle of rotation. Fractured instruments were examined by scanning electron microscopy (SEM). Data were analyzed with Shapiro-Wilk and Kruskal-Wallis tests, and the significance level was set at 5%.

The WGG group showed greater cyclic fatigue resistance than the PG and TNG groups (p < 0.05). In the torsional fatigue test, the TNG group showed a higher angle of rotation, followed by the PG and WGG groups (p < 0.05). The TNG group was superior to the PG group in torsional resistance (p < 0.05). SEM analysis revealed ductile morphology, typical of the 2 fracture modes: cyclic fatigue and torsional fatigue.

Reciprocating WGG instruments showed greater cyclic fatigue resistance, while TNG instruments were better in torsional fatigue resistance. The significance of these findings lies in the identification of the instruments’ clinical applicability to guide the choice of the most appropriate instrument and enable the clinician to provide a more predictable glide path preparation.

This study evaluated the effect of different nanoparticulated zinc oxide (nano-ZnO) and conventional-ZnO ratios on the physicochemical properties of calcium aluminate cement (CAC).

The conventional-ZnO and nano-ZnO were added to the cement powder in the following proportions: G1 (20% conventional-ZnO), G2 (15% conventional-ZnO + 5% nano-ZnO), G3 (12% conventional-ZnO + 3% nano-ZnO) and G4 (10% conventional-ZnO + 5% nano-ZnO). The radiopacity (R_ad), setting time (S_et), dimensional change (D_c), solubility (S_ol), compressive strength (C_st), and pH were evaluated. The nano-ZnO and CAC containing conventional-ZnO were also assessed using scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Radiopacity data were analyzed by the 1-way analysis of variance (ANOVA) and Bonferroni tests (p < 0.05). The data of the other properties were analyzed by the ANOVA, Tukey, and Fisher tests (p < 0.05).

The nano-ZnO and CAC containing conventional-ZnO powders presented particles with few impurities and nanometric and micrometric sizes, respectively. G1 had the highest R_ad mean value (p < 0.05). When compared to G1, groups containing nano-ZnO had a significant reduction in the S_et (p < 0.05) and lower values of D_c at 24 hours (p < 0.05). The C_st was higher for G4, with a significant difference for the other groups (p < 0.05). The S_ol did not present significant differences among groups (p > 0.05).

The addition of nano-ZnO to CAC improved its dimensional change, setting time, and compressive strength, which may be promising for the clinical performance of this cement.

This study aimed to evaluate in vitro the effects of the self-adhesive resin cements RelyX U200 (3M ESPE) and seT PP (SDI Limited) on murine macrophages and the interference of the photoactivation.

Cell viability assays, cell adherence, yeast phagocytosis of Saccharomyces boulardii and production of reactive oxygen species (ROS) were performed in the presence of capillaries containing the respective self-adhesive cement when photoactivated or not.

After long periods of contact, both types of cements, when not photoactivated, are more cytotoxic for macrophages. The seT PP cement when only chemically activated seems to interfere more negatively in the process of phagocytosis of yeasts S. boulardii. Both types of cements interfere in the cell adhesion process, independent of photoactivation. None of the types of cements tested was able to induce the production of ROS.

Our results highlight the great importance of the photoactivation of self-adhesive resin cements in the dental clinic, since RelyX U200, when photoactivated, presented the best results within the evaluated parameters.

This study investigated the impact of micro-computed tomography (micro-CT)-based voxel size on the analysis of material/dentin interface voids and thickness of different endodontic cements.

Following root-end resection and apical preparation, maxillary premolars were filled with mineral trioxide aggregate (MTA), Biodentine, and intermediate restorative material (IRM) (n = 24). The samples were scanned using micro-CT (SkyScan 1272; Bruker) and the cement/dentin interface and thickness of materials were evaluated at voxel sizes of 5, 10, and 20 µm. Analysis of variance and the Tukey test were conducted, and the degree of agreement between different voxel sizes was evaluated using the Bland and Altman method (p < 0.05).

All materials showed an increase in thickness from 5 to 10 and 20 µm (p < 0.05). When evaluating the interface voids, materials were similar at 5 µm (p > 0.05), while at 10 and 20 µm Biodentine showed the lowest percentage of voids (p < 0.05). A decrease in the interface voids was observed for MTA and IRM at 20 µm, while Biodentine showed differences among all voxel sizes (p < 0.05). The Bland-Altman plots for comparisons among voxel sizes showed the largest deviations when comparing images between 5 and 20 µm.

Voxel size had an impact on the micro-CT evaluation of thickness and interface voids of endodontic materials. All cements exhibited an increase in thickness and a decrease in the void percentage as the voxel size increased, especially when evaluating images at 20 µm.

The aim of this study was to verify the match between 5 shades of composites from different manufacturers with a shade guide and among the systems using a portable spectrophotometer.

Shade measurements were performed on specimens of Z350 XT (3M ESPE), Charisma Diamond (Heraeus Kulzer GmbH), Esthet X-HD (Dentsply Caulk), and Empress Direct (Ivoclar-Vivadent) for shades A1, A2, A3, B1, and C3 using a Vita Easyshade spectrophotometer (Vita Zahnfabrik) against a white background. Corresponding shades of Vitapan Classical (Vita Zahnfabrik) guide were measured likewise and shade variation (ΔE) was calculated based on International Commission on Illumination L*a*b* parameters. The ΔE of the composites in each shade was compared by one-way analysis of variance and Tukey's post hoc test (α = 0.05).

All composites presented ΔE > 3.7 compared with the shade guide. Variation in shades A3, B1, and C3 was significantly different for all composites. ΔE of Z350 XT was significantly lower for A1 than for the other shades, whereas ΔE of Z350 XT and Charisma Diamond were significantly lower for A2 than for the other shades.

No composite shade matched with the shade guide. Equivalent shades of the restorative composite from different manufacturers may show clinically noticeable ΔE.

This study evaluated 2 nickel-titanium rotary systems and a complementary protocol with an ultrasonic tip and a small-diameter instrument in flattened root canals.

Thirty-two human maxillary second premolars with flattened canals (buccolingual diameter ≥4 times larger than the mesiodistal diameter) at 9 mm from the radiographic apex were selected. The root canals were prepared by ProDesign Logic (PDL) 30/0.01 and 30/0.05 or Hyflex EDM (HEDM) 10/0.05 and 25/0.08 (n = 16), followed by application of the Flatsonic ultrasonic tip in the cervical and middle thirds and a PDL 25/0.03 file in the apical third (FPDL). The teeth were scanned using micro-computed tomography before and after the procedures. The percentage of volume increase, debris, and uninstrumented surface area were analyzed using the Kruskal-Wallis, Dunn, Wilcoxon, analysis of variance/Tukey, and paired and unpaired t-tests (α = 0.05).

No significant difference was found in the volume increase and uninstrumented surface area between PDL and HEDM (p > 0.05). PDL had a higher percentage of debris than HEDM in the middle and apical thirds (p < 0.05). The FPDL protocol resulted in less debris and uninstrumented surface area for PDL and HEDM (p < 0.05). This protocol, with HEDM, reduced debris in the middle and apical thirds and uninstrumented surface area in the apical third (p < 0.05).

High percentages of debris and uninstrumented surface area were observed after preparation of flattened root canals. The HEDM, Flatsonic tip, and 25/0.03 instrument protocol enhanced cleaning in flattened root canals.

This study aimed to evaluate the effect of improper positioning single-peak and multi-peak lights on color change, microhardness of bottom and top, and surface topography of bulk fill and incremental composites after artificial aging for 1 year.

Bulk fill and incremental composites were cured using multi-peak and single-peak light-emitting diode (LED) following 4 clinical conditions: (1) optimal condition (no angulation or tip displacement), (2) tip-displacement (2 mm), (3) slight tip angulation (α = 20°) and (4) moderate tip angulation (α = 35°). After 1-year of water aging, the specimens were analyzed for color changes (ΔE), Vickers hardness, surface topography (Ra, Rt, and Rv), and scanning electron microscopy.

For samples cured by single-peak LED, the improper positioning significantly increases the color change compared to the optimal position regardless of the type of composite (p < 0.001). For multi-peak LED, the type of resin composite and the curing condition displayed a significant effect on ΔE (p < 0.001). For both LEDs, the Vickers hardness and bottom/top ratio of Vickers hardness were affected by the type of composite and the curing condition (p < 0.01).

The bulk fill composite presented greater resistance to wear, higher color stability, and better microhardness than the incremental composite when subjected to improper curing. The multi-peak LED improves curing under improper conditions compared to single-peak LED. Prevention of errors when curing composites requires the attention of all personnel involved in the patient's care once the clinical relevance of the appropriate polymerization reflects on reliable long-term outcomes.

This systematic review evaluated the efficacy of the supplementary use of the XP-endo Finisher on bacteria content reduction in the root canal system.

In-vitro studies evaluating the use of the XP-endo Finisher on bacteria content were searched in four databases in July 2020. Two authors independently screened the studies for eligibility. Data were extracted, and risk of bias was assessed. Data were meta-analyzed by using random-effects model to compare the effect of the supplementary use (experimental) or not (control) of the XP-endo Finisher on bacteria counting reduction, and results from different endodontic protocols were combined. Four studies met the inclusion criteria while 1 study was excluded from the meta-analysis due to its high risk of bias and outlier data. The 3 studies that made it to the meta-analysis had an unclear risk of bias for at least one criterion.

No heterogeneity was observed among the results of the studies included in the meta-analysis. The study excluded from the meta-analysis assessing the bacteria counting deep in the dentin demonstrated further bacteria reduction upon the use of the XP-endo Finisher.

This systematic review found no evidence supporting the supplementary use of the XP-endo Finisher on further bacteria counting the reduction in the root canal.