Selen Küçükkaya Eren

Sealing ability and adaptation of root-end filling materials in cavities prepared with different techniques: Küçükkaya EREN et al.

The aim of this study was to evaluate the sealing ability and marginal adaptation of calcium silicate‐based cements (CSCs) in root‐end cavities prepared by ultrasonic and laser tips. A total of 72 extracted human maxillary incisor teeth were randomly divided as 60 teeth in experimental groups and 6 teeth each for positive and negative control groups. Specimens in experimental groups were obturated, their root‐end resections were performed and randomly divided into six groups (n = 10) as follows: G1: Ultrasonic retrotip + MTA, G2: Ultrasonic retrotip + Calcium Enriched Mixture (CEM), G3: Ultrasonic retrotip + Biodentine, G4: Er:YAG laser tip + MTA, G5: Er:YAG laser tip + CEM, G6: Er:YAG laser tip + Biodentine. The sealing ability was measured by fluid transport method. Six specimens from each experimental group were randomly selected to analyze marginal adaptation and prepared for scanning electron microscopy (SEM) analysis. Micrographs were scored and also analyzed using Image J software. Data were analyzed with; two‐way ANOVA, Bonferroni, Kruskall–Wallis, Mann–Whitney‐U, Siegel & Castellan, and Spearman correlation coefficient tests. No significant difference was found between materials regarding the sealing ability and marginal adaptation (p > 0.05). Significantly greater fluid movement and poor marginal adaptation were seen for materials placed in cavities prepared by laser tips (p < 0.05). Positive correlation was found between the results of scoring and Image J analysis of SEM images (r = 0.596, p < 0.001). Fluid transport method and SEM analysis gave similar results suggesting the use of ultrasonic‐retrotips for preparing root‐end cavities which are going to be filled with one of these CSCs.

Adaptation of mineral trioxide aggregate to dentine walls compared with other root-end filling materials: A systematic review

This systematic review analysed the literature comparing marginal adaptation of mineral trioxide aggregate (MTA) with other filling materials in root-end cavities. The PubMed, Ovid, Web of Science, SCOPUS, and Cochrane library databases were searched using appropriate keywords related to root-end filling materials and adaptation. Of 38 articles assessed, 20 met the inclusion criteria. No in vivo study was identified. In 10 studies, MTA gave the best marginal adaptation results, but no significant differences were found between MTA and any of the tested filling materials in seven studies. There was great variability in the study designs including analysed surface, unit of gap measurement and magnification amount during analysis. On the basis of available evidence, MTA presented good marginal adaptation to dentine walls. This review identified the need for the development of standardised methods to evaluate the adaptation property of root-end filling materials in ex vivo studies as well as in clinical studies evaluating outcome.

Efficacy of different irrigant protocols and application systems on sealer penetration using a stepwise CLSM analysis

This study compared several irrigation protocols and application systems for sealer penetration into dentinal tubules. Single‐rooted‐human teeth were divided into 5 experimental groups (n = 15) and a control group (n = 5), according to final irrigation protocols: standard needle irrigation (SNI); Vibringe; Vibringe + NaviTip FX (Vibringe NFX); Endo Spray (ES); and passive‐ultrasonic‐irrigation (PUI). Following obturation of the root canals, the percentage of the sealer penetration was measured at different depths using stepwise CLSM analysis. The sealer penetration in the experimental groups was significantly higher than the control group at all levels (p < .05). No significant differences were observed between Vibringe and SNI or Vibringe NFX, ES, and PUI at all depths (p > .05). The Vibringe NFX, ES, and PUI groups allowed deeper sealer penetration than SNI at 100, 250, and 500 μm levels (p < .05). The irrigant activation, the needle design, and the application form (syringe or spray) may impact the quality of the seal that is achieved with root canal filling.

Effect of Instrumentation Techniques and Preparation Taper on Apical Extrusion of Bacteria

Introduction The aim of this in vitro study was to evaluate the effects of different root canal instrumentation techniques and preparation tapers on the amount of apically extruded bacteria. Methods The root canals of 98 extracted human mandibular incisors were contaminated with Enterococcus faecalis suspension. After incubation at 37°C for 24 hours, the root canals were instrumented with K3 rotary files in a crown‐down (CD) or full‐length linear instrumentation technique (FL) by using 3 different root canal tapers (0.02, 0.04, and 0.06). During instrumentation, apically extruded bacteria were collected into vials containing saline solution. The microbiological samples were taken from the vials and incubated in brain‐heart agar medium for 24 hours, and the numbers of colony‐forming units (CFUs) were determined. The obtained results were analyzed with t test and one‐way analysis of variance for the comparisons between the instrumentation techniques (CD and FL) and the preparation tapers (0.02, 0.04, and 0.06), respectively. Tukey honestly significant difference test was used for pairwise comparisons. Results The preparation taper had no effect on the number of CFUs when a FL instrumentation technique was used (P > .05). There was a statistically significant difference in the CFUs between FL and CD techniques when the preparation taper was 0.02 (P < .05). There was no statistically significant difference between the 0.04 and 0.06 preparation tapers in any of the instrumentation techniques (P > .05). Conclusions Using a 0.02 taper in a CD manner results in the least amount of bacterial extrusion. The instrumentation technique did not seem to affect the amount of bacterial extrusion when 0.04 and 0.06 taper instruments were used for cleaning and shaping the root canal space. HighlightsApical extrusion of intracanal bacteria occurs with all instrumentation techniques.CD and FL techniques showed similar bacterial extrusion regardless of taper.CD instrumentation with .02 files resulted in the lowest extrusion.

Mineral content analysis of root canal dentin using laser-induced breakdown spectroscopy

Objectives This study aimed to introduce the use of laser-induced breakdown spectroscopy (LIBS) for evaluation of the mineral content of root canal dentin, and to assess whether a correlation exists between LIBS and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) methods by comparing the effects of irrigation solutions on the mineral content change of root canal dentin. Materials and Methods Forty teeth with a single root canal were decoronated and longitudinally sectioned to expose the canals. The root halves were divided into 4 groups (n = 10) according to the solution applied: group NaOCl, 5.25% sodium hypochlorite (NaOCl) for 1 hour; group EDTA, 17% ethylenediaminetetraacetic acid (EDTA) for 2 minutes; group NaOCl+EDTA, 5.25% NaOCl for 1 hour and 17% EDTA for 2 minutes; a control group. Each root half belonging to the same root was evaluated for mineral content with either LIBS or SEM/EDS methods. The data were analyzed statistically. Results In groups NaOCl and NaOCl+EDTA, the calcium (Ca)/phosphorus (P) ratio decreased while the sodium (Na) level increased compared with the other groups (p < 0.05). The magnesium (Mg) level changes were not significant among the groups. A significant positive correlation was found between the results of LIBS and SEM/EDS analyses (r = 0.84, p < 0.001). Conclusions Treatment with NaOCl for 1 hour altered the mineral content of dentin, while EDTA application for 2 minutes had no effect on the elemental composition. The LIBS method proved to be reliable while providing data for the elemental composition of root canal dentin.

Effect of root canal sealers on the fracture resistance of endodontically treated teeth: a systematic review of in vitro studies

ObjectiveThe purpose of this study was to systematically review and critically analyze the published data of in vitro studies testing the effect of root canal sealers on the fracture resistance of endodontically treated teeth.MethodsA comprehensive literature search was performed by using the Medline, Scopus, Web of Science, Cochrane, and Open Grey databases. A hand search of the reference lists of identified articles was also performed. Two reviewers critically assessed the studies for eligibility against inclusion and exclusion criteria and performed data extraction. Evaluation of the risk of bias of the studies was performed.ResultsA total of 48 studies were assessed for eligibility. Of these, 20 met the inclusion criteria and were included in the systematic review. All studies had a medium or high risk of bias. Although the majority of the studies reported that the use of root canal sealers increased the fracture resistance of endodontically treated teeth, conflicting evidence was found for the reinforcing effect of resin, glass ionomer, and calcium silicate-based sealers while there was moderate evidence for zinc oxide eugenol-based sealers in favor of no reinforcing effect.ConclusionOn the basis of available evidence, the use of root canal sealer increases the fracture resistance of endodontically treated teeth. However, included studies presented considerable risk of bias. Regarding the comparisons among the sealers, no conclusions could be drawn for the superiority of one sealer type to another.Clinical relevanceA considerable heterogeneity was found in the methodologies of included studies. Therefore, this review strongly suggests the development of standardized methods to test the reinforcement effect of root canal filling materials in in vitro studies.

Effect of Post Space Preparation on Apical Obturation Quality of Teeth Obturated with Different Techniques: A Micro–computed Tomographic Study

Introduction: The purpose of this study was to evaluate the obturation quality of root canals filled with different techniques and to determine whether post space preparation had an effect on the quality of apical obturation using micro–computed tomographic (micro‐CT) imaging. Methods: The root canals of 30 human mandibular premolar teeth were instrumented, and the specimens were divided into 3 groups according to the obturation technique used: cold lateral compaction (CLC), warm vertical compaction (WVC), or single‐cone (SC) techniques. The specimens were stored at 37°C and 100% humidity for 1 week. Then, the coronal root filling material was removed in order to create a post space. Micro‐CT scans were performed before and after post space preparation for the volumetric analysis of voids and filling materials. Data were analyzed using repeated‐measures analysis of variance and Bonferroni tests. Results: The CLC and SC groups showed a significantly greater percentage volume of voids than the WVC group (P < .05), whereas no significant difference was found between the CLC and SC groups before and after post space preparation (P > .05). The post space preparation caused a significant increase in the percentage volume of voids in the CLC and SC groups (P < .05). No significant difference was detected in the percentage volume of voids in the WVC group after post space preparation (P > .05). Conclusions: No root fillings were void free. The WVC group presented the best obturation quality. The post space preparation negatively influenced the apical integrity of the filling materials in the CLC and SC groups, whereas it had no significant effect in the WVC group. HighlightsThe warm vertical compaction (WVC) group presented the best obturation quality before and after post space preparation.The post space preparation negatively influenced the apical integrity of the filling materials in the cold lateral compaction and single‐cone groups, whereas it had no significant effect on the WVC group.

Comparison of triple antibiotic paste removal by different irrigation techniques

This study compared different irrigation techniques in triple antibiotic paste (TAP) removal from root canals. Fifty-six maxillaryanterior-teeth were filled with TAP for 28 days, and assigned into 5 experimental groups (n=10): Syringe irrigation (SI), NaviTip FX (NFX), Vibringe-Syringe irrigation (V-SI), NaviTip FX-Vibringe (V-NFX), passive ultrasonic irrigation (PUI) and positive and negative control groups (n=3 for each). Following the removal of the medicament, the remaining medicament was evaluated using 4-grade scoring-system. V-NFX and NFX showed similar performances (p>0.05) while V-NFX was significantly more efficient than SI and PUI (p<0.05) at all parts of root canals. VSI was less efficient at apical part when compared to NFX and V-NFX (p<0.05) while not significantly different from PUI and SI at all parts of the root canals (p>0.05). Regarding different parts of the root canals, V-SI and PUI were significantly less efficient at the apical part (p<0.05). In conclusion, the brush form of irrigation delivery with and without sonic activation improved the removal of TAP from the root canals when compared to ultrasonic activation, syringe irrigation or sonic activation alone.

Interaction of backfilling techniques and MTA plugs with additives: Fracture strength and adaptation analyses

The aims were to evaluate the effects of different additives on the adaptation of mineral trioxide aggregate (MTA) plugs before and after different backfilling techniques and analyze the interference of filling procedures on the fracture resistance of simulated immature teeth. The apical parts of 60 teeth were filled with MTA mixed with distilled water (DW), propylene glycol (PG) or calcium chloride (CaCl2) and backfilled with cold lateral condensation (CLC) or warm vertical compaction (WVC). The specimens were subjected to adaptation analysis and fracture testing. CaCl2 addition resulted in poor marginal adaptation, while PG addition significantly decreased the fracture values (p<0.05). WVC technique negatively affected the marginal adaptation of MTA-CaCl2 plugs and decreased the fracture values of teeth with MTA-PG plugs (p<0.05). Mixing MTA with DW can be recommended as apical plug when the remaining root canal space is going to be filled with either CLC or WVC techniques.

A novel model for testing the efficiency of removal of calcium hydroxide from complex root canal anatomies

The purpose of this study was to evaluate the efficacy of several irrigation protocols in the removal of calcium hydroxide [Ca(OH)2 ] from simulated internal root resorption cavities in a complex root canal anatomy model. The 20° to 35° curved mesiobuccal roots of 94 maxillary molars were sectioned longitudinally; internal resorption cavities were prepared in the apical third of the canal walls. Calcium hydroxide was placed into the cavities and the root halves reassembled. Four teeth were used as controls, and 90 teeth were randomly divided into six experimental groups (n = 15), according to the irrigation protocols used: syringe irrigation; H2 O2 (HP); Navitip FX; Vibringe-syringe; Vibringe-NaviTip FX; ultrasonically activated irrigation (UAI) using an ultrasonic K-file. In the HP group, 2.5% NaOCl and 3% H2 O2 were used, while 2.5% NaOCl and 17% EDTA were used in the remaining groups. Stereomicroscope images and radiographs were used to measure the remaining Ca(OH)2 . The model proved to be suitable for simulating complex anatomy. Positive correlation was found between stereomicroscope and radiographic analyses (P < 0.05). UAI removed significantly more Ca(OH)2 than the other experimental groups (P < 0.05). The HP group was the least efficient protocol (P < 0.05). It would appear that a reliable model has been developed that simulates complex root canal anatomy. Irrigant activation protocols enhanced Ca(OH)2 removal.