Gates Glidden Drills Research Articles

Comparison of Apical Leakage between Immediate Versus Delayed Post Space Preparation using AH-Plus Sealer

Background: Most endodontic failures result from incomplete root canal sealing. For successful treatment, obturation materials must have excellent sealing properties, and the techniques used should minimally impact their sealing effectiveness.Objective: To compare the apical seal integrity utilizing the AH-PLUS sealer in immediate versus delayed post-space preparation.Materials and Methods: This study was conducted at the Operative Dentistry Department of Liaquat University of Medical and Health Sciences, Jamshoro. Fourteen teeth were randomly split into two groups of seven. Lateral compaction used AH Plus sealer (Dentsply) and gutta-percha. In group 1, Gates Glidden drills at 9000 rpm and a heated instrument created a post gap immediately after obturation, leaving 4 mm of gutta-percha apically. Group 2 teeth were immersed in saline at 37°C for one week before creating the post space using the same technique. The AH Plus sealer was used to test apical seal integrity in both groups.Results: In group 1 (Immediate post-space preparation) and group 2 (Delayed post-space preparation), 2 (28.6%) and 0 (0.0%) of 14 teeth had no apical seal integrity loss, while 5 (71.4%) and 7 (100.0%) had it. Compared to group 2 (Delayed post-space preparation), group 1 (Immediate post-space preparation) had considerably lower mean apical leakage (P-Value = 0.049) at 0.28 ± 0.38 mm.Conclusion: Apical seal integrity achieved by utilizing the AH-PLUS sealer is more favorable in immediate post-space preparation as compared to delayed post-space preparation after obturating the root canal system.Keywords: Apical, Integrity, Leakage, Preparation, Sealer.

Comparative evaluation of blood contamination on the push-out bond strength of mineral trioxide aggregate, Biodentine, and bone cement in furcation perforation repair: An in vitro study

ABSTRACT Aim: This in vitro study was designed to compare the effect of blood contamination on the push-out bond strength of mineral trioxide aggregate (MTA), Biodentine, and bone cement. Materials and Methods: Seventy-eight human mandibular molars with furcation were selected and decoronated at the cementoenamel junction. The samples were mounted 3 mm below the furcation area into the acrylic resin. A perforation in the center of the furcation was made using a round carbide bur size 3 with a diameter of 1.2 mm. Then, the perforation was enlarged up to a standardized diameter of 1.3 mm using a size 5 Gates-Glidden drill. The samples were randomly divided into three groups. Based on blood contamination status, each group (n = 26) was further subdivided into two subgroups (n = 13). Whole fresh human blood was obtained from the principal investigator of the research group. A 27-gauge syringe was used to inject blood into the perforated furcal area. A piece of gelatin was packed under the furcal area using a condenser. MTA, Biodentine, and bone cement were mixed according to the manufacturer’s recommendations and compacted into the perforation. A universal testing machine was used to evaluate the push-out bond strength. Statistical Analysis: The results were analyzed using one-way analysis of variance followed by Tukey’s post hoc test (P < 0.05). Results: In the experimental groups with blood contamination, Group 2A exhibited statistically significant push-out bond strength values compared with Group 1A and Group 3A. In the groups without blood contamination, Group 2B showed statistically significant push-out bond strength values compared with Group 1B and Group 3B. Irrespective of the blood contamination status, Group 3 exhibited higher push-out bond strength values than Group 1, with no statistically significant difference between the groups. No significant difference was observed within the groups. Conclusion: Biodentine showed promising results as a better perforation repair material irrespective of the status of blood contamination. Bone cement can be a viable alternative material for furcation perforation repair compared with MTA.

The use of modified nickel–titanium rotary file for preparing staging platform to retrieve instrument fragments from narrow and curved canal

Abstract Staging platform (SP) uses a modified Gates Glidden (GG) to help retrieve separated instruments deep in the root canal. However, GG drills may cause damage or severe dentin loss. A 46-year-old male patient was referred to the endodontic postgraduate clinics complaining of pain on biting related to the mandibular right second molar (#47). The preoperative periapical radiograph of #47 showed a previously initiated root canal treatment with an approximately 8-mm separated instrument in the apical third of a curved mesiolingual canal. A nickel–titanium (NiTi) rotary file size 25/0.04 was flattened with a carbide bur. The modified file was then used to create a centered SP. After SP was achieved, an ultrasonic tip was used at lower power for the trephination of dentin. The fragment became loose, and retrieval was achieved. The use of a modified NiTi rotary file presented a safe and alternative option to establish SP for instrument retrieval instead of using GG drills.

Antibacterial Efficacy of Graphene Nanoparticles against Enterococcus faecalis: In Vitro Study.

This study compared the antimicrobial efficacy of nanographene (NG) particles with chlorhexidine (CHX) and calcium hydroxide (Ca(OH)2) against Enterococcus faecalis. Forty extracted human mandibular premolar teeth were cleaned using a scaler, and the middle-third of the root (6 mm) was decoronated using a rotary diamond disk. The inner diameter of the teeth was made consistent using Gates Glidden Drills #3, treated with ethylene diamine tetra-acetic acid and sodium hypochlorite before sterilization. The samples were then contaminated with E. faecalis grown in Tryptic soy broth for 21 days. Tooth samples were then randomly divided into four groups: Group I (Control), untreated saline; Group II, Ca(OH)2; Group III, CHX; and Group IV, NG. The assessment of bacterial growth was carried out by harvesting dentin chips at the end of 1, 3, and 7 days. The colonies were physically counted and tabulated after 24 hours from seeding. Statistical analysis of the collected data was performed with analysis of variance and Tukey's post hoc test using SPSS Version 20.0. The contaminated dentine blocks irrigated with NG (0.5 µg) and CHX (0 ± 0; p < 0.001) had no growth of E. faecalis colonies compared to blocks of Ca(OH)2 (10 ± 21) and saline (927 ± 455). All concentrations of NG (0.5 and 1.0 µg) showed effectiveness higher (p < 0.001) than 2% CHX when measured by the zone of inhibition against E. faecalis. CONCLUSION: It may be concluded that NG is effective against growth of E. faecalis and may be used as a promising antimicrobial agent during root canal treatment. However, further studies should be done to investigate the effect of NG against other dental pathogens.

Comparative Evaluation of the Efficacy of ProTaper & Mtwo Rotary Retreatment System and Conventional Hand H-files for Removal of Gutta-percha from Root Canal - A Stereomicroscopic Study.

Root canal retreatment aims to eliminate or substantially reduce the microbial load from the root canal and removal of previous root filling materials is the primary goal of nonsurgical retreatment. To comparatively evaluate the effectiveness of ProTaper retreatment files, Mtwo retreatment files, and Hedstrom files along with Gates Glidden (GG) Drill by using a stereomicroscope for the detection of remaining gutta-percha after root canal retreatment using a stereomicroscope. Forty-five test samples were divided into three experimental groups (15 samples each), such as Group A-ProTaper retreatment files; Group B-Mtwo retreatment files; Group C-Hedstrom files along with Gates Glidden Drill. After routine endodontic treatment in the test samples, gutta-percha was removed from the test samples as per the division of different retreatment file systems. Further, test samples were divided longitudinally and were evaluated under the stereomicroscope. Stereomicroscopic images were captured and analysed under Image Analyser Software-Image J. One-way ANOVA test was used for comparison of gutta-percha removal between the groups and Tukey's post hoc test was used for pairwise comparisons. The least remaining filling material was seen in specimens retreated with the ProTaper universal system. The highest remaining filling material was seen in specimens retreated with Hedstrom file with Gates Glidden Drill. All experimental test techniques left gutta-percha remnants within the root canal. ProTaper universal rotary retreatment system proved to be an efficient method of removing gutta-percha and left relatively less volume in comparison with other test systems.

Root canal treatment of a rhizomegaly tooth 36 mm long right permanent maxillary canine – A case report

Permanent maxillary canines can have variable length even exceeding 31 mm. The present case report is about the root canal treatment of a permanent maxillary canine with an unusual length of 36 mm A 37-year old male patient has come to Dental centre, Cannanore suffering from decay on tooth #13 with extra-oral swelling corresponding to right cheek. Root canal treatment was completed, and the tooth was noticed to have an atypical length of 36 mm. A 31 mm long Hand protaper file was used to do cleaning and shaping and Gates glidden drills of sizes 2 &amp; 3 were used to enlarge the canal orifice to receive gutta percha during obturation.

The Efficacy of Different Laser Applications on Dentin Sealing in Preventing Discoloration Induced by Mineral Trioxide Aggregate.

The aim of this in vitro study was to evaluate the effect of the pre-application of a dentin-bonding agent and the application of different lasers on the prevention of tooth discoloration caused by mineral trioxide aggregate (MTA) in the presence of blood. Sixty extracted human anterior teeth were selected, with root lengths standardized to 10 mm and root canals shaped using Gates-Glidden drills #3 to #5. The samples were divided into six groups (n = 10): Group 1 with no surface treatment and Groups 2 to 6 with Optibond universal adhesive and Neodymium yttrium aluminum garnet (Nd:YAG), Erbium yttrium aluminum garnet (Er:YAG), Erbium-chromium-yttrium-scandium-gallium-garnet (Er:Cr:YSGG), and diode laser applications, respectively. Root canals were filled with fresh human blood, and ProRoot MTA and a collagen barrier were then placed. Color changes were measured with a spectrophotometer at 0, 7, 30, 90, and 180 days post MTA placement. Color differences (∆E) were analyzed using a two-factor mixed-design ANOVA with the Sidak method (p = 0.05). All treatment groups exhibited discoloration above the acceptability threshold. Although all treatment approaches exhibited less color change compared to the control group (p < 0.05), there was no significant difference among them in terms of preventing color change (p > 0.05). It was determined that none of the methods could guarantee 100% prevention of discoloration caused by MTA-blood contact.

The Efficacy of Different Antibiotic Compounds in Regenerative Treatment of Immature Necrotic Teeth.

Objectives: Endodontic treatment of immature teeth poses a significant challenge, especially in achieving a proper seal using traditional obturation methods. Revascularization presents itself as an alternative approach to this problem, and the application of triple antibiotic paste (TAP) has been suggested as a means to achieve disinfection during the procedure. This study aims to compare the antibacterial properties of three different antibiotic combinations to assess their effectiveness on root canal disinfection. Materials and Methods: Eighty samples were employed to assess the impact of three antibiotic combinations on Enterococcus faecalis, Escherichia coli, Streptococcus mutans, and a combination thereof. The antibiotics included metronidazole, ciprofloxacin, and cefaclor (CCM), the commonly used TAP, and a double antibiotic paste (DAP) composed of metronidazole and ciprofloxacin. Dentin shavings collected using Gates-Glidden drills were placed in microtubes containing a 2ml standard bacterial suspension. Microtube contents were diluted and cultured on BHI agar plates, with colony counts calculated based on dentine shavings' weight in CFU/mg. Kruskal-Wallis and Dunn's post-hoc tests were used for statistical analysis and P<0.05 was considered significant. Results: A significant difference in mean CFU was observed among all bacterial groups (P<0.05). Dunn's post-hoc analysis showed a significant difference only between the control group (methylcellulose) and the other antibiotic groups. There was no significant difference between the other antibiotic groups in two-by-two comparisons. Conclusion: There was no significant difference in the antimicrobial properties of DAP, TAP and CCM. Therefore, DAP and CCM may be used during regenerative treatment.

Standardization of vertical root resection during socket shield technique in immediate implant placement

Objectives. The aim of the present study was to standardize an accurate and significant technique of root separation during socket shield technique. Patients and methods. Two phases of the study were conducted. In vitro study was performed on 20 extracted single-rooted anterior teeth. The second phase was clinical application of the new technique on 10 patients seeking to restore their badly decayed anterior teeth in the esthetic area with immediate implant placement utilizing the socket shield technique. Decoronation was done. The root canal was mechanically enlarged by means of manual assorted files. Canals were further enlarged with Gates Glidden drills. Peeso Reamer drills were used till the root was entirely separated into two parts (buccal &amp; palatal). The palatal root was cautiously removed when the labial and palatal root halves were sufficiently separated. In case the root to be removed was endodontically treated, Gutta-percha was mechanically removed using Gates Glidden, &amp; Gutta-percha solvent to remove the coronal and apical parts. Outcomes. Using manual endodontic K-files, Gates Glidden burs, and Peeso Reamer’s drills in separating the single-rooted teeth into two halves is a reproducible, and reliable procedure during socket shield technique. Conclusions. This technique prevents possible complications of root sectioning during socket shield technique with immediate implant placement. It preserves surrounding soft tissue structures, and labial shield during shield preparations, maintains the integrity of the labial plate of bone during extraction. Additionally, it offers total root apex removal by entirely separating the palatal portion from the labial shield.

Evaluation of The Accuracy of Two Apex Locators For Determining The Working Length of Endodontically Retreated Curved Mesial Roots of Maxillary Molar Teeth : An Ex Vivo Study

Objective: To evaluate the accuracy of PROPEX PİXİ (Dentsply Sirona, Ballaigues, Switzerland) and Apex ID (Sybron Endo, Orange, CA, USA) in determining the working lengths of curved mesial roots of upper molars during the retreatment procedure. Method: Twenty curved mesial roots of upper molar teeth were selected. Canals were shaped with ProTaper Next instruments (Dentsply Sirona) up to X3. The canal lengths were determined with a microscope (Carl Zeiss GmbH, Oberkochen, Germany) at 2,5X magnification (DM) and then also detected electronically (EM1P and EM1A) with PROPEX PİXİ (Dentsply Sirona) and Apex ID (Sybron Endo) in an alginate model. Specimens were then obturated using a size X3 master gutta-percha cone and an epoxy resin-based root canal sealer. Seven days later, the coronal part of the filling was removed with a Gates Glidden drill size 3 and for the middle part Protaper Universal Retreatment File D2 used. Working lengths electronically were detected again by two different apex locaters (EM2P and EM2A). Data were analysed by using the Wilcoxon Signed Rank and Mann Whitney u test. The analyses were carried out with MedCalc Statistical Software. Results: No significant difference was found between direct measurements (DM) and electronic measurements before and during retreatment for PROPEX PİXİ (P=0.135) and Apex ID (P=0.232). Also there was no significant difference between two apex locaters before (P=0.108) and during retreatment (P=0.242) Conclusion: PROPEX PİXİ and Apex ID were considered accurate for the root canal length determination during retreatment procedure. Keywords: Apex locator, curved molar, retreatment, working lenght

In vitro reduction in Enterococcus faecalis count following root canal preparation with Neolix and XP shaper rotary files

Introduction: The main goal of root canal treatment is to decrease the count of intracanal microorganisms and their byproducts. This study aimed to assess the efficacy of Neolix and XP Shaper rotary files for the reduction of Enterococcus faecalis (E. faecalis) count in the root canal system. Materials and Methods: This in vitro, experimental study evaluated 58 single-rooted single-canal teeth. The teeth were randomly divided into two experimental groups (n = 25) for root canal instrumentation with Neolix and XP Shaper files and positive and negative control groups (n = 4). All teeth were primarily instrumented with #20 K-file and #2 and #3 Gates-Glidden drills. The smear layer was removed using 17% ethylenediaminetetraacetic acid and 5.25% sodium hypochlorite. The teeth were then autoclave sterilized and the root canals in all groups, except for the negative control, were inoculated with E. faecalis. All teeth were then CO2 incubated for 24 h. Primary samples were collected. Next, the root canals in Group 1 were instrumented with Neolix, while the root canals in Group 2 were instrumented with XP Shaper. Root canals in the positive control group were only rinsed with saline. Secondary samples were collected after instrumentation. The number of colonies formed on the blood-agar was counted before and after instrumentation. Results: The negative control group showed no bacterial growth. The positive control group showed a 14.11% reduction in bacterial count. The mean percentage of reduction in bacterial colony count was 92.92% and 87.79% in the Neolix and XP Shaper groups, respectively. The difference in this regard was significant between the two experimental groups with different apical sizes (Mann–Whitney test, P = 0.02). Conclusion: Both files caused a significant reduction in E. faecalis count. However, Neolix had a superior efficacy for canal cleaning compared with XP Shaper.

Comparative Evaluation of Antimicrobial Efficacy of Various Antibiotic Pastes and Calcium Hydroxide Using Chitosan as a Carrier Against Enterococcus faecalis: An In Vitro Study.

The use of intracanal medicaments between appointments can serve as an important aid in the sterilization of the root canal system. Calcium hydroxide is commonly used, but it is not completely effective against Enterococcus faecalis. A triple antibiotic paste (TAP) is used but has the problem of tooth discoloration. Double antibiotic paste (DAP) or modified TAP (MTAP) has been suggested to solve this. Chitosan has been used as a vehicle in pharmacology, and it has inherent antibacterial properties too. This study compares the efficacy of DAP and MTAP using chitosan as a vehicle with calcium hydroxide. Sixty single-rooted teeth were taken and decoronated with a length of 13 mm. Biomechanical preparation (BMP) was done with #3 Gates-Glidden (GG) drills, 17% ethylenediaminetetraacetic acid (EDTA), and 5.25% sodium hypochlorite (NaOCl) used for irrigation. These were kept in microcentrifuge tubes with 1 ml brain heart infusion (BHI)broth. Contamination was done with E. faecalis strain for 21 days. DAP and MTAP pastes were prepared and added to the chitosan solution. Groups were divided into 10 each, each medicament with saline or chitosan as the vehicle. The microbial load was measured at the end of two and seven days. The level of significance was kept at p = 0.05. Statistical analysis was done with the Kruskal-Wallis test and analysis of variance (ANOVA). DAP and MTAP groups with chitosan showed a significant reduction in the microbial load when compared to calcium hydroxide with chitosan. DAP and MTAP with chitosan can be effective intracanal medicaments against E. faecalis in refractory endodontic cases.

Comparison of Root Dentinal Crack Formation after Coronal Pre-Flaring using Different Rotary Instruments: An In vitro Study.

The aim of this study was to see the incidence of cracks in root dentin after coronal flaring using various rotary instruments such as Gates Glidden (GG) drills, ProTaper Universal SX, OneFlare, and HyFlex EDM. Seventy freshly extracted premolar teeth with single canal were collected. All the teeth were randomly divided into five groups of fourteen each (n = 14), of which one group served as the control and the rest of the four groups were instrumented with GG drills, ProTaper Universal SX, OneFlare, and HyFlex EDM, respectively. The GG drills resulted in a higher rate of crack formation in root dentin (P < 0.05) than the ProTaper Universal SX, OneFlare, and HyFlex EDM instruments (P > 0.05). The use of GG drills resulted in more crack formation. However, the results for the ProTaper Universal SX, OneFlare, and HyFlex EDM flaring instruments were less in terms of crack formation.

Pretreatment of Root Dentin Using Photon-Induced Photoacoustic Streaming, Photodynamic Therapy, and Riboflavin with EDTA as a Final Irrigant to Improve Bond Integrity of Glass Fiber Post.

Objective: To evaluate the outcome of post space disinfection using Er,Cr:YSGG laser (ECYL), riboflavin photosensitizer (RFP), and photon-induced photoacoustic streaming (PIPS) along with ethylene diamine tetra acetic acid (EDTA) as final irrigant on the bond values of glass fiber post (GFP) to the canal wall. Materials and methods: Forty human mandibular premolars were subjected to root canal treatment after decoronation till the cementoenamel junction. Post space was prepared using a Gates-Glidden drill leaving 4 mm of gutta perch at the apical third of the root section. Random allocation of samples was performed into four groups based on the post space disinfection (n = 10 each): Group 1: 1% RFP and 17% EDTA, group 2: 5.25% sodium hypochlorite (NaOCl) and 17% EDTA (control), group 3: PIPS and 17% EDTA, and group 4: ECYL and 17% EDTA. GFP was luted using Rely X Unicem. A universal testing machine and stereomicroscope were used to assess the push-out bond strength (PBS) and failure mode, respectively. Analysis of variance determined the PBS amid different experimental groups at three root levels. Multiple group comparison using means of tested groups was identified using post hoc Tukey. Results: The coronal third of group 2 (5.25% NaOCl +17% EDTA) demonstrated the highest PBS (8.83 ± 0.11 MPa). However, the lowest bond integrity (4.15 ± 0.52 MPa) was displayed in an apical third of group 1 (RFP +17% EDTA). The intergroup comparison revealed that 5.25% NaOCl +17% EDTA at all three levels demonstrated comparable outcomes of PBS with PIPS +17% EDTA and ECYL +17% EDTA specimens (p > 0.05). However, riboflavin +17% EDTA demonstrated the lowest bond strength (p < 0.05). Conclusions: Er,Cr: YSGG and PIPS in combination with 17% EDTA demonstrated comparable outcomes of bond score with those of conventional gold standard irrigation regime 5.25% NaOCl.

Surface conditioning of PEEK post using Nd: YVO4 laser, photodynamic therapy, and sulfuric acid on the pushout bond strength to canal dentin

AimTo assess the push-out bond strength (PBS) of polyetheretherketone (PEEK) post-to-root dentin using post-surface conditioners i.e., Neodymium-doped yttrium orthovanadate (Nd: YVO4) and Riboflavin (RF) and Rose Bengal (RB) mediated photodynamic therapy (PDT) compared to sulfuric acid (SA). Materials and MethodsDecoronation of forty human single-rooted premolar teeth was performed. Followed by chamber opening, working length (WL) was established at 15 mm. Root canal preparation was completed using ProTaper Ni-Ti rotary system till F3 finishing file along with root canal disinfection. The canals were dried with paper cones followed by obturation using gutta-percha (GP) and AH sealer. Post space was prepared by drilling out 11 mm of GP using a Gates Glidden drill #3. PEEK posts were fabricated using the CAD-CAM system and then randomly allocated into 4 groups based on the post-surface conditioning (n = 10). Group 1: SA, group 2: PDT RF, group 3: PDT RB, and group 4: Nd: YVO4 laser. The PEEK post was then cemented in their respective canal. PBS and failure mode assessment were performed using a universal testing machine and stereomicroscope at 40x magnification. The SBS data set was subjected to a one-way analysis of variance (ANOVA) and Tukey's Post Hoc test at a significance level of 0.05. ResultsThe samples in group 4 (Nd: YVO4 laser) coronal third (7.99±0.24 MPa) demonstrated the highest PBS. The apical third of samples in group 1 PEEK post surface conditioned with SA (5.15± 0.52 MPa) exhibited the minimum values of PBS. Intergroup comparison analysis showed that samples in group 1 (SA), group 2 (RF activated by PDT), group 3 (RB activated by PDT), and group 4 (Nd: YVO4 laser) demonstrated comparable outcomes of bond scores (p>0.05) ConclusionNeodymium-doped yttrium orthovanadate (Nd: YVO4) and riboflavin and Rose bengal activated by photodynamic therapy (PDT) have been investigated as potential alternatives for the surface conditioning of PEEK (polyetheretherketone) posts.

In vivo Study to Evaluate the Effect of Instrument Size on the Accuracy of Three Different Apex Locators when Various Irrigation Solutions are used in Vital and Non-Vital Teeth.

Root canal success requires working length (WL) optimization. The current study examined how different apex locators on vital and non-vital teeth responded to instrument size. Three hundred patients (180 men and 120 women) receiving root canal therapy at the department of Conservative Dentistry and Endodontics were evaluated. Therefore, we determined that 200 of the patients' teeth (100 vital and 100 non-vital teeth from the upper and lower jaws' first molars) qualified for inclusion in our study. The pulp chamber was accessed using a sterile round bur. The coronal region of the root canal was preflared with successive Gates Glidden drills (Mani Inc. Japan) and irrigated with any one of the solutions 3% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), or 17% ethylenediaminetetraacetic acid (EDTA) solution after checking canal patency with a size #10 K file, where (#-number). Later, the working length was established using Ingle's technique and a radiovisiograph (RVG) 0.5 mm short of the radiographic apex. Two endodontists approved this RVG. Overall, the #15 K file and apex locators did not differ from Ingle's method. While the #8 K file differs significantly from all apex locators, the #10 K file showed a significant difference with all apex locators except Root ZX with 2% CHX (P = 0.06). Irrigation didn't influence apex locators' accuracy. Even in the presence of irrigating solutions, electronic apex locator (EAL) can be utilized to calculate the working length with accuracy. The apex locators #15 k files, #10 k files, and #8 k files showed the most promising results.

Comparing the Fracture Resistance of Dentine Posts and Glass Fiber Posts in Primary Maxillary Incisors: An In Vitro Study.

Background/purpose An ideal post material should have physical and mechanical properties similar to dentin. Another problem when restoring primary teeth that have undergone root canal treatment is the availability of materials that are resorbed in the exfoliation process in a manner similar to the structure of the natural tooth, allowing the normal eruption of a permanenttooth. This study aimed to evaluate the effect of using dentine posts on the fracture resistance of endodontically treated primary incisors in comparison to glass fiber posts. Materials and methods The study sample consisted of 30 extracted primary maxillary incisors that were randomly distributed into the following two groups: group I (experimental, n=15), which was restored with dentine posts; and group II (control, n=15), which was restored with glass fiber posts. Initially, 10 extracted single-root permanent teeth were collected to prepare 20 dentine posts using a computer-aided design-computer-aided manufacturing (CAD-CAM) machine. Then, the crowns of maxillary primary incisors were cut and the canals were prepared and filled. Then the preparation for a post was made using Gates Glidden drills, and the posts were placed with an extension of 3 mm within the canal in both groups, then the crown was built and the teeth were placed within acrylic cubes and subjected to 500 thermocycling. Fracture resistance was recorded using a Testometric machine (Rochdale, England: Testometric Co. Ltd.). Data were analyzed using an independent Student's t-test. Results The dentine posts group showed greater fracture resistance (246.3 N) than the glass fiber posts group (206.3 N). A statistically significant difference (p=0.004) was found between the two groups in favor of the dentine posts group. Conclusion Based on this in vitro study, the dentin posts used in restoring severely decayed primary maxillary incisors showed greater fracture resistance than glass fiber posts. Therefore, the use of dentin posts as intra-canal stabilizers in maxillary primary incisors is a good alternative for glass fiber posts.

Comparative Evaluation of Antimicrobial Efficacy of Sodium Hypochlorite, Triphala, Eucalyptus, and Carvacrol against Enterococcus faecalis: An In Vitro study.

This study aimed to evaluate the antimicrobial effect of sodium hypochlorite (NaOCl), Triphala, Eucalyptus, and carvacrol on Enterococcus faecalis as the most common microorganism isolated from infected root canals. Seventy-five mandibular premolar teeth were randomly distributed into five study groups: 5.25% NaOCl, 10% Triphala, 1.25% Eucalyptus, 0.6% carvacrol, and negative control (saline) group. Samples were taken using paper points from the canal spaces and using Gates-Glidden (GG) drills from dentinal tubules; after sample culturing, the colony forming unit (CFU) were counted, which was analyzed by the Wilcoxon signed-rank test. All irrigants have shown a reduction of microorganisms in the root canal space. After the use of NaOCl and Eucalyptus, the bacterial count was significantly reduced in the canal, as well as dentin sampling, as compared to Triphala and carvacrol. The antimicrobial efficiency of all irrigants against E. faecalis revealed a significant difference (p < 0.05). All irrigants exerted significant antimicrobial activity against E. faecalis. Around 1.25% of Eucalyptus was the most effective irrigant than 5.25% of NaOCl, Triphala, and carvacrol. Panchal VV, Dahake PT, Kale YJ, et al. Comparative Evaluation of Antimicrobial Efficacy of Sodium Hypochlorite, Triphala, Eucalyptus, and Carvacrol against Enterococcus faecalis: An In Vitro study. Int J Clin Pediatr Dent 2022;15(5):514-519.

Buckling resistance, torque, and force generation during retreatment with D-RaCe, HyFlex Remover, and Mtwo retreatment files.

This study compared the buckling resistance of 3 nickel-titanium (NiTi) retreatment file systems and the torque/force generated during retreatment. The buckling resistance was compared among the D-RaCe (DR2), HyFlex Remover, and Mtwo R25/05 retreatment systems. J-shaped canals within resin blocks were prepared with ProTaper NEXT X3 and obturated by the single-cone technique with AH Plus. After 4 weeks, 4 mm of gutta-percha in the coronal aspect was removed with Gates-Glidden drills. Retreatment was then performed using DR1 (size 30, 10% taper) followed by DR2 (size 25, 4% taper), HyFlex Remover (size 30, 7% taper), or Mtrwo R25/05 (size 25, 5% taper) (15 specimens in each group). Further apical preparation was performed with WaveOne Gold Primary. The clockwise torque and upward force generated during retreatment were recorded. After retreatment, resin blocks were examined using stereomicroscopy, and the percentage of residual filling material in the canal area was calculated. Data were analyzed using 1-way analysis of variance with the Tukey test. The HyFlex Remover files exhibited the greatest buckling resistance (p < 0.05), followed by the Mtwo R25/05. The HyFlex Remover and Mtwo R25/05 files generated the highest maximum clockwise torque and upward force, respectively (p < 0.05). The DR1 and DR2 files generated the least upward force and torque (p < 0.05). The percentage of residual filling material after retreatment was not significantly different between file systems (p > 0.05). NiTi retreatment instruments with higher buckling resistance generated greater clockwise torque and upward force.

Evaluation of wear promoted by post preparation drill using CBCT images

Aim: To evaluate, in vitro, the residual dentin thickness in the palatal root of premolars after preparation of the post space with Post Preparation drill and to compare with the Gates-Glidden and Largo drills by means of cone beam computed tomography. Methodology: 21 premolars were selected and randomized into 3 groups: G1 - Post-preparation drills; G2 - Gates-Glidden drills nº 2 and nº 3; G3 - Wide Drills nº 1 and nº 2. The residual dentin thickness in seven cuts for the mesial, distal, buccal and palatal points was measured in three stages: initial (not prepared), after instrumentation for apical file nº 35 and after preparation powders with Kodak CS 9000C 3D Extraoral Imaging System and CS 3D Image v. 3.4.3. Software. The root canal area was analyzed in three stages using VRMesh Reverse v. 7.6.1. Software. Statistical significance was set at 5%. Linear and area measurements data were analyzed using the Kruskal-Wallis test. Results: Post-preparation drills performed similarly to other drills in linear and area analysis. Conclusion: Post-preparation drills showed similar performance to Gates-Glidden and Largo drills in the analysis of residual dentin thickness for the preparation of the pin space.