Dentinal Penetration Research Articles

Comparative Micro-CT Evaluation of Dentinal Tubule Penetration of BIO-C and AH Plus Jet Root Canal Sealer Using Three Intra-Canal Activation Techniques

ABSTRACT Objectives: This study aimed to compare the effectiveness of three intra-canal sealer activation techniques: ultrasonic, Lentulospiral activation, and GP cone-mediated ultrasonic activation on dentinal tubule penetration of a bioceramic (BIO-C) root canal sealer and AH Plus jet sealer with single cone obturation. Materials and Methods: Eighty single-rooted straight canal teeth were randomly divided into two main groups – BIO-C sealer and AH Plus jet sealer (n = 40). Each group was further divided into four subgroups, based on the three activation techniques: ultrasonics, Lentulospiral, gutta-percha cone-mediated ultrasonic, and a control. The canals were obturated using the single cone obturation technique. Dentinal penetration of sealers was measured using Micro-CT at the coronal, middle, and apical portions of root canals. Results: Greater sealer penetration was observed with ultrasonic and Lentulospiral agitation compared to GP-mediated ultrasonic agitation for both sealers. Conclusion: BIO-C yielded better results with ultrasonic and Lentulospiral agitation, while AH Plus performed better with ultrasonic agitation.

Advent of novel vehicle in regenerative endodontics and its effect on dentinal penetration of intracanal medicaments

Context: Regenerative endodontic procedures allow continued root development, but open apices limit mechanical debridement which implores the need for an effective and potent intracanal medicament to disinfect the canal space. Aim: This study aimed to assess the effect of nanobubble (NB) water on dentinal penetration of intracanal medicaments in simulated immature teeth. Materials and Methods: A total of 60 freshly extracted mandibular premolars were prepared to simulate blunderbuss canals. Canals were irrigated with 5.25% NaOCl and 17% ethylenediaminetetraacetic acid by a final rinse of saline. Teeth were divided into 3 groups with different medicaments which were further subdivided into two subgroups with saline and NB water as vehicle, respectively. The longitudinal sections of teeth were evaluated using stereomicroscopy. Statistical Analysis Used: Two-way ANOVA and Tukey’s post hoc test were used. Results: The results indicated that samples with NB water as vehicle showed better penetration than their counterparts that were carried with saline. The highest penetration was seen in the middle third of the root. Conclusions: It could be concluded that NB water enhanced the dentinal penetration of all antimicrobial agents and calcium hypochlorite with NB water showed maximum penetration depth.

Glycolic acid and ultrasonic activation: Effects on smear layer removal, dentin penetration, dentin structure and bond strength of the root dentin filling material.

Glycolic acid (GA) has been tested as enamel and dentin etchant, and final irrigant for smear layer removal. This study evaluated the effects of GA and ultrasonic activation (US) on smear layer removal, dentin penetration, dentin structure and bond strength of the root dentin filling material. The root canals of 210 teeth were distributed into four test groups: smear layer removal (N=50), dentin penetration (N=50), dentin structure (N=10) and bond strength (N=100). In all tests, specimens were subdivided into five groups, according to the final irrigation protocols: G1:distilled water(DW)+US; G2:17% EDTA; G3:17% GA; G4:17% EDTA+US; G5:17% GA+US. Scanning electronic microscopy, confocal laser scanning microscopy, transmission electronic microscopy and the push-out test were performed to evaluate smear layer removal, dentin penetration, dentin structure and bond strength, respectively. Statistical analysis was performed for each evaluation (α=5%). Groups 4 (EDTA+US) and 5 (GA+US) were the most effective on smear layer removal, with no statistical differences from each other (p>0.05). The maximum penetration depth into dentinal tubules was observed for group 5(GA+US), being statistically different from all other groups (pp<0.05). Group 5(GA+US) showed the largest collagen dispersion area, being statistically different from groups 1(DW+US), 2(EDTA) and 3(GA) (pp<0.05), and similar to group 4(EDTA+US) (p>0.05). The highest BS values for filling and restorative material were observed for all experimental groups, being statistically different from control group (pp<0.05), with higher predominance of cohesive failure. The association of GA and US promotes better smear layer removal, dentin penetration and collagen dispersion, with no influence on bond strength of the root dentin filling/restorative material. Key words:EDTA, final irrigation, glycolic acid, ultrasonic activation.

Comparative assessment of nanosized intracanal medicaments on penetration and fracture resistance of root dentin - An in vitro study.

The antimicrobial potential of conventional medicaments is reduced due to their limited permeability. The use of calcium hydroxide (CH) is known to reduce the root strength. Nano intracanal medicaments have the following advantages over conventional such as higher surface area and chemical reactivity, and due to its nanosize, have better penetrability, supporting its possible use as an intracanal medicament. Nano versions of CH, chitosan (CS), CS + CH, curcumin (T), and its conventional forms are used in our study. The aim of this study was to evaluate and compare the depth of penetration of nanosized intracanal medicaments and their effect on fracture resistance of root dentin. Eighty extracted single-rooted teeth were used after decoronation. Canals were enlarged up to size 30 (0.04° taper) using Neoendo instruments (Orikam, India). Teeth were randomly assigned to two broad groups based on the type of intracanal medicament used; Group A: control (conventional) (n = 40) and Group B: nanosized intracanal medicaments (n = 40). Each group was subdivided into four experimental groups (n = 10), Group A1: CH, Group A2: CS, Group A3: curcumin (T), Group A4: CS + CH, Group B1: nano calcium hydroxide (NCH), Group B2: nano CS (NCS), Group B3: nano curcumin (NT), and Group B4: NCS + nano calcium hydroxide (NCS + NCH). All the specimens were stored in a humidor at 37°C for 4 weeks. Out of 10 specimens from each group, five specimens were used for evaluating the depth of penetration using a confocal laser scanning electron microscope, and the remaining five specimens were used for evaluating fracture resistance in a universal testing machine at the end of 4 weeks. Data were analyzed using one-way ANOVA and intergroup comparison using Tukey's post hoc multiple comparison test. The highest fracture resistance was seen with NCS and the maximum depth of penetration with nano calcium hydroxide (NCH). The fracture resistance and depth of penetration at a 4-week interval were higher in nano forms compared to their micro-sized counterparts with all groups. The coronal section presented the highest depth of penetration of intracanal medicaments followed by the middle and least in the apical section of root dentin with all groups.

Medium-term evaluation of the bond strength and dentin penetration of self-adhesive resin cements to root dentin.

Medium-term evaluate the bond strength and tag formation in root dentin using self-adhesive cements Maxcem Elite (MCE), Relyx U200 (RU2), SeT PP (SPP) and Megalink (MGL) compared to conventional cement Relyx ARC (ARC) for glass fibre post cementation. One hundred bovine incisors roots were endodontically treated and divided into 5 groups (n = 20) according to the cementation system: MCE, RU2, SPP, MGL and ARC. All cementation systems were evaluated at 24 h (1) and 12 months (2) after post cementation. Specimens from the cervical, middle and apical thirds of the root were submitted to push-out bond strength test and confocal laser microscopy to verify the dentin penetration. The adhesive failure mode was classified as adhesive, cohesive and mixed. Data were analysed by one-way ANOVA and Tukey tests (α = 5%). ARC-1 and ARC-12 showed the highest bond strength (P < 0.05). ARC showed the greatest tag extension, regardless of the third (P < 0.05). The most frequent failure mode in the 24-h analysis was cohesive, regardless of the cement used. For the 12-month analysis, mixed failure was the most frequent. Conventional cement (ARC) showed the highest bond strength and tag extension, regardless of the evaluation period. In all cementation systems, the bond strength decreased after 12 months. © 2023 Australian Dental Association.

Dentinal Tubule Penetrability and Bond Strength of Two Novel Calcium Silicate-Based Root Canal Sealers.

Once the chemo-mechanical preparation of root canals is finished, achieving a complete seal of the root canal system becomes crucial in determining the long-term success of endodontic treatment. The important goals of root canal obturation are to minimize leakage and achieve an adequate seal. Thus, a material that possesses satisfactory mechanical characteristics, is biocompatible, and has the ability to penetrate the dentine tubules adequately is needed. This study aimed to compare the penetrability and bond strength between two calcium silicate-based sealers and an epoxy resin-based sealer, as well as examine the relationship between penetrability and bond strength for the different sealers. Thirty-nine recently extracted single-rooted human premolar teeth were instrumented and divided evenly into three groups (n = 13), according to the sealer used for obturation: AH Plus Jet, EndoSequence, and AH Plus Bioceramic Sealer. Three teeth (30 slices) were randomly selected out of each for analysis using confocal laser scanning microscopy to assess penetrability. The remaining ten teeth (90 slices) in each group were subject to push-out tests using a universal testing machine. All teeth were sectioned into nine transverse slices of 0.9 mm thickness for their respective tests (apical, middle, coronal). AH Plus Jet exhibited significantly lower penetrability and significantly higher bond strength compared to EndoSequence BC sealer (p = 0.002) and AH Plus Bioceramic Sealer (p = 0.006). There was no significant difference between EndoSequence BC sealer and AH Plus Bioceramic Sealer in terms of either penetrability or bond strength. No correlation was found between penetrability and bond strength. Within the limitation of this study and regardless of the location in the canal, the bioceramic based root canal sealers appeared to perform better than the epoxy resin-based sealer in terms of dentinal penetration rate. Further studies are required to compare other biomechanical properties of bioceramic sealers including setting characteristics and bacterial leakage.

Comparative evaluation of dentinal penetration of sealer with extracanal and intracanal heating of sodium hypochlorite: An in vitro study

ABSTRACT Aim: The aim of this study was to evaluate and compare the depth and percentage of sealer penetration into dentinal tubules using extracanal and intracanal heated NaOCl in the irrigation protocol using a confocal laser scanning microscope. Methods: Thirty extracted central incisors prepared till F4 ProTaper Gold were randomly distributed into three groups (n = 10 each) depending on the final irrigation protocol. Group C – nonheated 3% NaOCl, group EC – extracanal heated 3% NaOCl, and group IC – intracanal heated 3% NaOCl. Final irrigation with different warming protocols along with sonic activation was performed. Canals were obturated with standardized F4 Protaper Gold gutta-percha cone coated with AH Plus sealer labeled with Rhodamine B dye. The transverse sections of samples at different levels were examined on a confocal microscope and analyzed using IOB software. Unpaired “t” test and Mann–Whitney U test were used for intergroup comparison; P &lt; 0.05. Results: The percentage of sealer penetration was significantly lower in group C as compared to group IC and EC at the coronal and middle third. Group C showed a lower depth of sealer penetration as compared to group EC and IC at all levels. The percentage and depth of sealer penetration were not significantly different between group EC and IC at all levels. Conclusion: Extracanal and intracanal heating of NaOCl significantly improves the percentage and depth of AH Plus sealer penetration in dentinal tubules.

Dentinal tubule penetration of sodium hypochlorite in root canals with and without mechanical preparation and different irrigant activation methods.

This study evaluated the dentinal penetration depth of 2.5% sodium hypochlorite (NaOCl) in root canals with and without preparation and different irrigant activation protocols. Sixty-three bovine mandibular incisors were randomly allocated to 6 groups (n = 10): G1, preparation + conventional needle irrigation (CNI); G2, preparation + passive ultrasonic irrigation (PUI); G3, preparation + Odous Clean (OC); G4, no preparation + CNI; G5, no preparation + PUI; G6, no preparation + OC; and CG (negative control; n = 3). Samples were filled with crystal violet for 72 hours. Irrigant activation was performed. Samples were sectioned perpendicularly along the long axis, 3 mm and 7 mm from the apex. Images of the root thirds of each block were captured with a stereomicroscope and analyzed with an image analysis software. One-way analysis of variance, followed by the Tukey post hoc test, and the Student's t-test were used for data analysis, with a significance level of 5%. The NaOCl penetration depth was similar when preparation was performed, regardless of the method of irrigation activation (p > 0.05). In the groups without preparation, G6 showed greater NaOCl penetration depth (p < 0.05). The groups without preparation had a greater NaOCl penetration depth than those with preparation (p = 0.0019). The NaOCl penetration depth was similar in groups with root canal preparation. Without root canal preparation, OC allowed deeper NaOCl penetration. The groups without preparation had greater NaOCl penetration than those undergoing root canal preparation.

Evaluation of dentin penetration of three different endodontic sealers in the presence and absence of the smear layer.

A sealer's ability to effectively and stably penetrate the dentinal tubules is an essential factor for selecting an effective root canal obturation material. Evaluation of the sealers' penetration into the dentinal tubules provides valuable data in the endodontic treatment outcome.

Interfacial characteristics of BIOfactor MTA and Biodentine with dentin.

The objective of this study was to characterize the interface between dentin and MTA-Angelus (Angelus, Londrina, Brasil), Biodentine (Septodont, France) and BIOfactor MTA (Imicryl, Konya, Turkey) using scanning electron microscopy (SEM), energy disperse X-ray spectroscopy (SEM-EDS) and confocal laser scanning microscopy (CLSM). Fifteen dentin segments were obtained from previously extracted single-rooted human teeth. Canal lumens were instrumented with diamond burs and then randomly filled with MTA-Angelus, Biodentine or BIOfactor MTA and placed in distilled water or Hanks' Balanced Salt Solution (HBSS) for 28-days. The samples were examined with SEM and the thickness of the interfacial layer measured. SEM-EDS analysis was performed to determine principal elemental composition of the material, dentin, and interfacial area. The marginal adaptation of cements to dentin was assessed by confocal microscopy and the percentage of material penetration was calculated. An interfacial layer was evident in approximately 70% of SEM images in both MTA-Angelus and BIOfactor samples. The thickness of interfacial layer was significantly higher in HBSS than in distilled water for all groups. MTA Angelus resulted in the thickest interfacial layer in distilled water while Biodentine had the thickest interfacial layer in HBSS. Calcium levels within the BIOfactor MTA-dentin interface were higher than both dentin and cement. Dentin penetration was higher in BIOfactor MTA and silicon was evident in all material-dentin interfaces. All calcium silicate-based materials promoted the formation of an interfacial layer. BIOfactor MTA exhibited promising characteristics with its good marginal adaptation even though it presented a moderately thick interfacial layer. RESEARCH HIGHLIGHTS: A distinguishable interfacial layer was observed in most of the samples within the BIOfactor MTA, MTA-Angelus and Biodentine groups. The elemental constitution of the interfacial layer was different from that of the calcium silicate based materials.

Effect of the Modified Methacrylate-Based Root Canal Sealer in Single-Cone Technique.

This study aimed to modify EndoREZ with 2.5% dimethylaminododecyl methacrylate (DMADDM) and 1% magnetic nanoparticles (MNP) to study its sealing property, penetration and long-term antibacterial and therapeutic effect in the single-cone technique (SCT) compared with EndoREZ and iRoot SP. Thirty single-root human maxillary premolars were assigned into three groups and obturated with three different root canal sealers by SCT. Every specimen was then scanned using micro-CT to analyze void fraction, and void volumes and confocal laser scanning microscope (CLSM) was used to study the dentin penetration. The long-term antimicrobial effects were tested in vitro before and after aging 1 and 4 weeks by the single-strain Enterococcus faecalis biofilm model. In addition, the beagle canine model of apical periodontitis (AP) was utilized to judge and compare the therapeutic effect of three sealers in SCT. The void fraction and void volumes of the modified root canal sealer were not significantly different from iRoot SP (p &gt; 0.05) but were lower than EndoREZ (p &lt; 0.05). The modified root canal sealant displayed a greater penetration, long-term antibacterial property, and treatment effect than the other groups (p &lt; 0.05). This indicated that after being modified with DMADDM and MNP, it showed better performance in SCT.

Push-Out Bond Strength and Dentinal Penetration of a Novel Herbal-Based Pulp Capping Agent: An In vitro Study

Background: Pulp capping agents should have proper sealing effect to enhance dental pulp tissue healing.&#x0D; Aim: The purpose of this study was to compare the effectiveness of grape seed extract (GSE) and Mineral trioxide aggregate (MTA) to penetrate to dentin and their push-out bond strength at two time intervals (1 and 3 months) when used as pulp capping agents either singly or combined to each other.&#x0D; Materials and Methods: This study was conducted on 120 human single-rooted anterior teeth. Sixty dentin discs were randomly divided into three groups (n=20) based on the material used; MTA, GSE, and a combination of MTA and GSE. A universal testing machine was used to determine the push-out bond strength for one and three months. At the same time intervals, extra 60 teeth with the same groups were utilized to quantify the degree of capping material penetration within the dentinal tubules using scanning electron microscopy (SEM). ANOVA with multiple comparison Post hoc test was used to evaluate the data where the p value was &lt; 0.05.&#x0D; Results: MTA had the highest push-out bond strength and penetration depth measurement into dentinal tubules at one month, followed by MTA combined with GSE, while GSE had the lowest push-out bond strength and penetration depth measurement. Nevertheless, GSE had the greatest values in both tests at 3 months, followed by MTA, while MTA coupled with GSE had the lowest value in both tests.&#x0D; Conclusion: Push out bond strength and dentinal penetration depth were improved with time except for the MTA group testing its dentinal penetration depth. GSE shows good push out bond strength and dentinal penetration depth.

Strength of Fiber Posts with Experimental TiO2 and ZrO2 Particle Bonding—An SEM, EDX, Rheometric and Push-Out Strength Study

The present study aimed to prepare experimental adhesives (EAs): 5 wt.% titanium dioxide (TiO2) adhesive; and 5 wt.% zirconium oxide (ZrO2) adhesive; and analyze their impact on bond integrity of fiber posts to root dentin, and viscosity. The EA was composed of: bisphenol A glycol dimethacrylate (BisGMA); triethylene glycol dimethacrylate (TEGDMA); 2-hydroxyethyl methacrylate (HEMA); and ethyl 4-dimethylamino benzoate and camphorquinone. TiO2 and ZrO2 particles were individually incorporated into the EA at 5 wt.%, to form two groups (5% TiO2 and 5% ZrO2). The adhesives, with particles, were characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy. The bonded interface was evaluated for adhesive–dentin penetration at the interface, using SEM. The study adhesive groups (EA, 5% TiO2 and 5% ZrO2) were analyzed for rheology and push-out bond strength of the fiber post to root dentin. Data were analyzed using analysis of variance and post hoc comparison. Both TiO2 and ZrO2 particles had irregular, non-uniform shapes. The EDX mapping showed the elemental presence of Ti (TiO2), Zr (ZrO2) and oxygen in formulated adhesives. The 5% TiO2 and 5% ZrO2 adhesives showed a decrease in viscosity, compared with the EA. Bond strength among the 5% TiO2 and 5% ZrO2 adhesives was statistically comparable (p &gt; 0.05), but higher than the control group (10.57 ± 1.45 MPa) (p &lt; 0.05). Reinforcement of the experimental dentin adhesive with 5% TiO2 or 5% ZrO2 increased the push-out bond strength of the fiber post to root dentin, in comparison with the EA. Particle-incorporated adhesives (5% TiO2 and 5% ZrO2) displayed decreased viscosity, compared with the EA (without particles).

Influence of dual rinse irrigation on dentinal penetration of a bioceramic root canal sealer: A Conofocal microscopic Analysis.

To evaluate the sealer penetration after applying dual rinse irrigant in comparison with sodium hypochlorite and 17% EDTA. Mandibular premolars were prepared by ProTaper Next and irrigated with NaOCl, NaOCl/Dual Rinse or NaOCl/EDTA and then obturated with a single-cone technique and bioceramic-based. Samples were observed using confocal laser microscopy, and the maximum depth of penetration was measured, as well as the percentage of sealer coating the canal wall and the penetration area of the sealer. One-way anova was used, followed by Tukey post hoc test. Sealer penetration area displayed a statistically significant difference between the tested groups (P < 0.05), and the highest percentage of sealer coating the canal wall and the greatest depth of sealer penetration were found in Group (NaOCl/Dual Rinse). Group (NaOCl/Dual Rinse) displayed better sealer penetration inside the dentinal tubules than Group (NaOCl/EDTA), while Group (NaOCl) showed the lowest sealer penetration.

Comparison of Dentinal Tubule Penetration between a Calcium Silicate-Based Sealer with Ultrasonic Activation and an Epoxy Resin-Based Sealer: A Study Using Confocal Laser Scanning Microscopy.

Objective The aim of this study was to compare the degree of dentinal penetration between an epoxy resin-based sealer applied by using two different filling methods and an ultrasonically activated calcium silicate-based sealer via confocal laser scanning microscopy (CLSM). Materials and Methods Forty-five extracted permanent maxillary premolars with type II canals (Vertucci’s classification) were subjected to the experiment. The root canals were instrumented and distributed randomly into the following three groups: AH Plus + continuous wave technique (AHC group); AH Plus + single cone technique (AHS group); and Endoseal MTA + single cone technique with ultrasonic activation (EMS) group. Each sealer was labeled with rhodamine B dye to allow visualization under CLSM. The sealer penetration depth in each sample was observed at 2 mm and 5 mm from the apex by using CLSM. The data were statistically analyzed by using analysis of variance or Kruskal–Wallis H test according to normality of variable (α = 0.05). Results In all groups, the maximum sealer penetration depth, mean fluorescence intensity, and sum fluorescence intensity values were higher at the 5-mm level than at the 2-mm level. At the 5-mm level, the EMS group showed the lowest value ( p = 0.02). At the 2-mm level, there were no statistically significant differences among any of the groups. The AHC group showed higher values than the other groups, but there was no statistically significant difference in the apical area where access of instruments was difficult. Conclusion The AHC group showed the highest dentinal tubule penetration, but had questionable filing efficacy in the apical area, which is of particular importance for the success of root canal treatment. Therefore, in areas such as the apical 2 mm of premolars with type II canals, which are difficult to access by using instruments such as heat carriers, other appropriate approaches may be required accordingly.

Protocols for Mechanical Cleaning of the Post Space on the Bond Strength Between Root Dentin and Cementation System.

To evaluate the effects of mechanical versus chemical cleaning protocols for cleaning the root dentin surface before cementation of fiberglass posts for their effect on the bond strength, failure mode, and dentinal penetration of the cementing agent using an etch-and-rinse adhesive system on dentin prepared to receive a fiberglass post. Forty roots of bovine teeth were endodontically treated and prepared for fiber post cementation. The specimens were randomized into 4 groups of 10: Control group (CO) - irrigation with 2.5% NaOCl; DW group- irrigation with distilled water; RB group - rotating brush for cleaning root canals, and CUI group - continuous ultrasonic irrigation. The fiberglass posts were cemented, and the specimens were immersed in distilled water for 6 months. A push-out test was performed on the cervical, middle, and apical thirds of the samples. Dentinal penetration of the cementing agent and the fracture pattern were evaluated by laser confocal microscopy. Statistical analysis was performed using analysis of variance (ANOVA) and post hoc Tukey tests (α=0.05). Results: The RB and CUI groups showed significantly higher bond strength values when compared to the Control and DW groups (p<0.05). In addition, in the control and DW groups, the apical third presented lower bond strength values when compared to middle and cervical thirds. While DW showed the highest incidence of adhesive type failure, CUI resulted in the highest dentinal penetration of the cementing agent (p<0.05). RB and CUI resulted in the highest bond strength between cementation system and root dentin. In addition, CUI favored greater dentinal penetration of fiberglass post cementing agent.

Temporary cement residues affect the bond strength and dentin penetration of self-adhesive resin cement in fiberglass post cementation.

This study evaluated the persistence of eugenol-containing (PR, Provy) or eugenol-free (RT, Relyx Temp, and TB, Temp Bond) temporary cement residues and its effects on push-out bond strength and dentinal penetration of the self-adhesive resin cement (Relyx U200). Eighty human roots were endodontically treated and post space prepared. Fourty specimens were distributed in four groups (n=10): Control (CO), without any clinical procedure, PR, RT, and TB, where a metallic post was cemented with one of the temporary cements. After metallic post removal, hemi sections post space were submitted to SEM analysis. Another specimens were distributed in similar groups, but fiberglass post was cemented using Relyx U200 cement and submitted to push-out bond strength and dentinal penetration cement analysis, in post space thirds. SEM analysis were evaluated by Kruskal-Wallis and Dunn tests, while bond strength and dentinal penetration were evaluated by ANOVA One-Way and Tukey test (p < .05). Only in apical thirds, PR, RT, and TB showed higher persistence of residues than CO. In bond strength, PR, RT, and TB showed lower values than CO, in all post space thirds (p < .05). But to dentinal penetration, PR, RT, and TB presented lower values than CO only in apical thirds (p < .05). There is the greatest persistence of temporary cement residues only in apical post space third, providing less dentinal penetration of the self-adhesive resinous cement. However, the previous use of temporary cements has negative effects on the bond strength cementation system, regardless of the third evaluated.

Sonic Activation Improves Bioceramic Sealer’s Penetration into the Tubular Dentin of Curved Root Canals: A Confocal Laser Scanning Microscopy Investigation

Background—The aim was to determine the influence of sonic activation in the tubular dentine penetration of bioceramic sealers. Methods—Forty mesiobuccal curved root canals of mandibular molars with an apical diameter smaller than #30 were prepared, divided into two groups, and filled with EndoSequence BC sealer, with or without sonic activation during its placement. Roots were sectioned at 3 mm, 6 mm, and 9 mm from the apex, producing a sample size of 120. The samples were evaluated using a confocal laser scanning microscope and comparing these images to the images obtained from an operatory microscope. The percentage of sealer penetration and maximum sealer penetration were evaluated. Statistical analysis was performed using the two-tailed Mann–Whitney U test, where statistical significance was set to p &lt; 0.05. Results—Sonic activation showed higher values for the percentage of sealer penetration when compared at the 9 mm level (p = 0.03). A higher value of maximum sealer penetration was observed at all levels when the sealer was activated. Conclusions—The sonic activation of bioceramic cement resulted in higher sealer penetration into dentinal tubules.

Evaluating Combined Effect of Oral Premedication with Ibuprofen and Dexamethasone on Success of Inferior Alveolar Nerve Block in Mandibular Molars with Symptomatic Irreversible Pulpitis: A Prospective, Double-blind, Randomized Clinical Trial

IntroductionThe success rate of inferior alveolar nerve block decreases exorbitantly in teeth with symptomatic irreversible pulpitis. The purpose of this prospective, double-blind, randomized clinical trial was to evaluate the combined effect of oral premedication with ibuprofen and dexamethasone on the success rate of inferior alveolar nerve block in mandibular molars with symptomatic irreversible pulpitis. MethodsNinety-four adult patients actively experiencing pain and diagnosed with symptomatic irreversible pulpitis willingly participated in this study. Preoperative pain was recorded on the Heft-Parker visual analog scale. Patients were randomly allocated to 4 different groups and received placebo, 0.5 mg dexamethasone, 800 mg ibuprofen, or a combination of 0.5 mg dexamethasone and 800 mg ibuprofen. One hour after oral premedication, all patients received standard inferior alveolar nerve block containing 2% lignocaine with 1:200,000 adrenaline. Access cavity preparation was initiated 15 minutes after the administration of anesthesia. Pain scores were recorded on VAS after anesthesia, at dentin penetration to pulp chamber opening, and on file placement. Success was defined as no or mild pain (0–54 mm) throughout the procedure. ResultsThe chi-square test was used for qualitative data comparison. The 1-way analysis of variance test and post hoc Bonferroni test showed a statistically significant difference between the combination of 0.5 mg dexamethasone and 800 mg ibuprofen group and the other 3 groups (P < .001). ConclusionsPreoperative administration of a combination of dexamethasone and ibuprofen improved the success rate of inferior alveolar nerve block in mandibular molars with symptomatic irreversible pulpitis.

Could the Calcium Silicate-Based Sealer Presentation Form Influence Dentinal Sealing? An In Vitro Confocal Laser Study on Tubular Penetration.

Dentinal tubule penetration influences root canal treatment sealing. The aim of this study was to compare dentinal penetration of two clinical presentations of silicate-based sealers using confocal laser. Sixty single-rooted human teeth from 50–70 year-old patients extracted for orthodontic/periodontal reasons were used. Canals were prepared using Mtwo system up to 35/0.04, with 5.25% NaOCl irrigation and final irrigation using 17% EDTA. Teeth were randomly assigned into study groups (ni = 20): EndoSequence BC sealer (ES, group 1), BioRoot RCS (BR, group 2); and a control group (nc = 20) with AH Plus (AHP). Root canals were obturated with 35/0.04 gutta-percha (single-cone technique). The samples were obtained from apical, middle, and coronal thirds. Dentinal tubule penetration depth and percentage of penetration around the canal perimeter were measured. The statistical analysis was performed using Mann Whitney U test and Wilcoxon t-test (95% confidence interval). ES exhibited a significantly higher penetration than AHP in apical and middle thirds (p < 0.05), and in middle and coronal thirds relative to BR (p < 0.05). The percentage of penetration around the canal perimeter was significantly higher for ES compared to BR in all thirds, but only in the apical third for AHP (p < 0.05). The pre-mixed silicate-based sealer exhibited better penetration than the powder/liquid one.