Dentsply DeTrey Research Articles

EVALUAREA MATERIALULUI DE OBTURAŢIE DE CANAL RESTANT DUPĂ DEZOBTURARE, FOLOSIND PROTAPER ROTATIV CU SAU FĂRĂ SOLVENŢI

The purposes of retreatment are to eliminate the cause for failure of initial endodontic treatment and to preserve the tooth as well. The aim of this study is a comparative evaluation of efficacy of Protaper rotaty retreatment instruments for gutta-percha removal with or without solvents specific both to the sealer and gutta-percha. Materials and methods: Forty single-rooted extracted teeth were randomly divided into 4 groups according to different methods of retreatment. The teeth were prepared with Protaper Universal system (Dentsply-Maillefer, Ballaigues, Switzerland) and filled using lateral condensation of gutta-percha and AH Plus (Dentsply DeTrey, Konstanz, Germany). All root canal fillings were removed using Protaper Universal Retreatment system (Dentsply-Maillefer, Ballaigues, Switzerland). During the retreatment procedure, in group 1 Resosolv (Pierre Rolland, Merignac, France) was used; in group 2 eucalyptol was used, in group 3 Endosolv E (Septodont, Paris, France) was used and in group 4 no solvent was used. The times required for retreatments and radiographycal evaluation after retreatment were recorded. Results: All root canals showed filling material remnants and group 1 with specific solvent for AH Plus recorded the shortest time. Conclusions: Although it is not possible to eliminate the entire filling material on the canal walls, the duration of retreatment was reduced by the use of a solvent specific to the sealer compared with a gutta-percha solvent or no solvent.

Post space preparation timing of root canals sealed with AH Plus sealer.

ObjectivesTo determine the optimal timing for post space preparation of root canals sealed with epoxy resin-based AH Plus sealer in terms of its polymerization and influence on apical leakage.Materials and MethodsThe epoxy polymerization of AH Plus (Dentsply DeTrey) as a function of time after mixing (8, 24, and 72 hours, and 1 week) was evaluated using Fourier transform infrared (FTIR) spectroscopy and microhardness measurements. The change in the glass transition temperature (Tg) of the material with time was also investigated using differential scanning calorimetry (DSC). Fifty extracted human single-rooted premolars were filled with gutta-percha and AH Plus, and randomly separated into five groups (n = 10) based on post space preparation timing (immediately after root canal obturation and 8, 24, and 72 hours, and 1 week after root canal obturation). The extent of apical leakage (mm) of the five groups was compared using a dye leakage test. Each dataset was statistically analyzed by one-way analysis of variance and Tukey's post hoc test (α = 0.05).ResultsContinuous epoxy polymerization of the material with time was observed. Although the Tg values of the material gradually increased with time, the specimens presented no clear Tg value at 1 week after mixing. When the post space was prepared 1 week after root canal obturation, the leakage was significantly higher than in the other groups (p < 0.05), among which there was no significant difference in leakage.ConclusionsPoor apical seal was detected when post space preparation was delayed until 1 week after root canal obturation.

Material Properties of a Tricalcium Silicate–containing, a Mineral Trioxide Aggregate–containing, and an Epoxy Resin–based Root Canal Sealer

IntroductionThe aim was to compare the solubility, radiopacity, and setting times of a tricalcium silicate–containing (BioRoot RCS; Septodont, St Maur-des-Fossés, France) and a mineral trioxide aggregate–containing sealer (MTA Fillapex; Angelus, Londrina, Brazil) with an epoxy resin–based sealer (AH Plus; Dentsply DeTrey, Konstanz, Germany). MethodsSolubility in distilled water, radiopacity, and setting time were evaluated in accordance with ISO 6876:2012. The solubility was also measured after soaking the materials in phosphate-buffered saline buffer (PBS). All data were analyzed using 1-way analysis of variance and the Student-Newman-Keuls test. ResultsAfter immersion for 1 minute in distilled water, BioRoot RCS was significantly less soluble than AH Plus and MTA Fillapex (P < .05). At all other exposure times, AH Plus was significantly less soluble than BioRoot RCS, whereas BioRoot RCS was significantly more soluble than the other 2 sealers (P < .05). All sealers had the same solubility in PBS and distilled water, except for BioRoot RCS after 28 days. At this exposure time, BioRoot RCS was significantly less soluble in PBS than in distilled water and less soluble than MTA Fillapex (P < .05). All BioRoot RCS specimens immersed in PBS had a surface precipitate after 14 and 28 days. The radiopacity of all sealers was greater than 3 mm aluminum with no statistical significant difference between the sealers (P > .05). The final setting time was 324 (±1) minutes for BioRoot RCS and 612 (±4) minutes for AH Plus. The difference was statistically significant (P < .05). MTA Fillapex did not set completely even after 1 week. ConclusionsThe solubility and radiopacity of the sealers were in accordance with ISO 6876:2012. PBS decreased the solubility of BioRoot RCS.

Remineralizing amorphous calcium phosphate based composite resins: the influence of inert fillers on monomer conversion, polymerization shrinkage, and microhardness.

AimTo determine if the addition of inert fillers to a bioactive dental restorative composite material affects its degree of conversion (DC), polymerization shrinkage (PS), and microhardness (HV).MethodsThree amorphous calcium phosphate (ACP)-based composite resins: without added fillers (0-ACP), with 10% of barium-glass fillers (Ba-ACP), and with 10% of silica fillers (Si-ACP), as well as commercial control (Ceram•X, Dentsply DeTrey) were tested in laboratory conditions. The amount of ACP (40%) and the composition of the resin mixture (based on ethoxylated bisphenol A dimethacrylate) was the same for all ACP materials. Fourier transform infrared spectroscopy was used to determine the DC (n = 40), 20 min and 72 h after polymerization. Linear PS and Vickers microhardness (n = 40) were also evaluated. The results were analyzed by paired samples t test, ANOVA, and one-way repeated measures ANOVA with Student-Newman-Keuls or Tukey’s post-hoc test (P = 0.05).ResultsThe addition of barium fillers significantly increased the DC (20 min) (75.84 ± 0.62%) in comparison to 0-ACP (73.92 ± 3.08%), but the addition of silica fillers lowered the DC (71.00 ± 0.57%). Ceram•X had the lowest DC (54.93 ± 1.00%) and linear PS (1.01 ± 0.24%) but the highest HV (20.73 ± 2.09). PS was significantly reduced (P < 0.010) in both Ba-ACP (1.13 ± 0.25%) and Si-ACP (1.17 ± 0.19%) compared to 0-ACP (1.43 ± 0.21%). HV was significantly higher in Si-ACP (12.82 ± 1.30) than in 0-ACP (10.54 ± 0.86) and Ba-ACP (10.75 ± 0.62) (P < 0.010).ConclusionIncorporation of inert fillers to bioactive remineralizing composites enhanced their physical-mechanical performance in laboratory conditions. Both added fillers reduced the PS while maintaining high levels of the DC. Silica fillers additionally moderately improved the HV of ACP composites.

Effect of sodium hypochlorite irrigation with or without surfactants on the bond strength of an epoxy-based sealer to dentin.

This study evaluated the effect of sodium hypochlorite (NaOCl) irrigation with or without surfactants on the bond strength of an epoxy-based sealer to the root canal dentin. Eighty decoronated single-rooted human mandibular premolars were instrumented using the rotary system. The roots were subsequently rinsed with 5ml 17% EDTA for 1min and then randomly divided into 3 test groups (n=20) and 1 control group (n=20) according to the type of irrigation with experimental 5% NaOCl (Wizard, RehberKimya, Istanbul, Turkey) solutions: Group 1: NaOCl-0.1% benzalkonium chloride; Group 2: NaOCl-0.1% Tween 80; Group 3: NaOCl-0.1% Triton X-100; control group: NaOCl without any surfactants. Five samples from each group were prepared for scanning electron microscopy to examine the surface of root canal dentin. The 15 samples remaining in each group were obturated with gutta-percha and AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) using the cold lateral compaction technique. A push-out test was used to measure the bond strength between the sealer and root canal dentin. Data were analyzed using two-way analysis of variance and Tukey's post hoc tests (P=0.05). The NaOCl-0.1% Triton X-100 group demonstrated the highest mean bond-strength values in all root thirds among the groups (P<0.05). However, the bond strength of the sealer in the NaOCl-0.1% benzalkonium chloride and NaOCl-0.1% Tween 80 groups did not differ from that in the control group (P>0.05). Additionally, the bond-strength values decreased in the corono-apical direction for all groups (P<0.05). NaOCl solution with Triton X-100 can provide higher bond strength of the epoxy resin-based sealer to root dentin compared to NaOCl solution wiithout any surfactant. The bond strength of sealer to dentin can be improved by the addition of the surfactants to NaOCl solution.

Do smear-layer removal agents affect the push-out bond strength of calcium silicate-based endodontic sealers?

To evaluate the effect of 17% ethylenediaminetetraacetic acid (EDTA), 2.25% peracetic acid (PA) or 10% citric acid (CA) on the push-out bond strength of calcium silicate-based endodontic sealers [MTA Fillapex (Angelus, Londrina, Brazil) and Total Fill BC Sealer (FKG, La Chaux-de-Fonds, Switzerland)] to root dentine after different periods of immersion in phosphate-buffered saline (PBS). AH Plus (Dentsply DeTrey, Konstaz, Germany) was used as a reference material for comparison. Thirty human maxillary incisors were selected and three 1-mm discs were obtained from the middle third of each root. On the axial surface of each disc, three 0.8-mm-diameter holes were drilled through the dentine. After standardized irrigation, each dentine disc from the same root was treated for smear-layer removal with one of the three tested chelating solutions: EDTA, PA or CA. After that, the holes were dried with paper points and filled with one of the three test root canal sealers. The filled dental slices were further immersed in PBS solution (pH 7.2) for 7days (T1) or 30days (T2) at 37°C, before the push-out assay. Friedman, Kruskal-Wallis and Mann-Whitney tests were used respectively to estimate the impact of the independent variables (solutions, sealers and period of PBS immersion) on the push-out bond strength. The level for significance was set at α=5% and data were further subjected to a Bonferroni correction. Solutions and periods of immersion did not significantly influence the displacement resistance (P=0.285, and P=0.104, respectively) of sealers to root dentine. On the other hand, the type of sealer significantly affected the push-out bond strength (P=0.000). AH Plus was associated with greater resistance to dislodgment compared with Total Fill BC Sealer and MTA Fillapex (P=0.000). MTA Fillapex resulted in the lowest push-out bond strength (P=0.000). The use of different chelating agents did not influence the push-out bond strength of endodontic sealers. Calcium silicate-based sealers had lower push-out bond strength values compared with a conventional epoxy resin-based sealer (AH Plus).

A Comparison of Cone-beam Computed Tomography with Periapical Radiography in the Detection of Separated Instruments Retained in the Apical Third of Root Canal–filled Teeth

IntroductionThis study compared the diagnostic efficacies of cone-beam computed tomographic (CBCT) imaging and periapical radiography (PR) in the detection of retained separated instruments located at the apical third of filled root canals. MethodsSixty single-rooted extracted human teeth were instrumented to size #25 and were randomly divided to a simulated 2-mm #30 K-file (stainless steel or nickel-titanium) segment separation at the apical third of the canal (n = 40) or a control group without a separated instrument (n = 20). The canals were obturated to the separated instrument or the working length for the teeth without an instrument using gutta-percha with AH26 (Dentsply DeTrey GmbH, Konstanz, Germany) or Roth sealer (Roth International Ltd, Chicago, IL). The teeth were invested in a mandible model simulating the bone density and imaged using CBCT imaging and PR. The images were evaluated separately by 2 calibrated observers twice with an interval of 4 weeks. Cohen kappa was used to evaluate the observer agreement. Receiver operating characteristic curve analysis was used to evaluate the discrimination ability. ResultsThe intraobserver kappa was 0.744 and 0.627, and between the observers, it was 0.593 and 0.275 for PR and CBCT imaging, respectively. Using PR, the mean sensitivity was 71.25%, and the specificity was 93.75%. Using CBCT imaging, the sensitivity and specificity were 41.25% and 71.25%, respectively. Although for PR the area under the curve values ranged between 0.75 and 0.91 (P < .05), for CBCT they ranged between 0.48 and 0.60 (P > .05), regardless of the instrument or the sealer type. ConclusionsPR performed better than CBCT imaging for the detection of retained separated instruments located at the apical third of extracted human root canal–filled teeth.

Evaluation of Apically Extruded Debris from Curved Root Canal Filling Removal Using 5 Nickel-Titanium Systems

IntroductionThis study evaluated the amount of apically extruded debris in the retreatment of curved root canals using different nickel-titanium (NiTi) systems: the ProTaper Universal Retreatment (Dentsply Maillefer, Ballaigues, Switzerland), Mtwo Retreatment (VDW, Munich, Germany), D-Race Retreatment (FKG Dentaire, La Chaux-de-Fonds, Switzerland), R-Endo Retreatment (Micro-Mega, Besançon, France), and Reciproc (VDW) systems. MethodsOne hundred human mandibular premolars with curved root canals were prepared with the Reciproc #25 .08 NiTi system filled with AH Plus Jet (Dentsply DeTrey, Konstanz, Germany) sealer and gutta-percha and divided into 5 groups (n = 20). The canal filling was removed with the ProTaper, Mtwo, D-Race, and R-Endo retreatment systems and Reciproc instruments. Final preparation was done with the Reciproc #40 .06 NiTi system. Extruded debris was collected in preweighed Eppendorf tubes. The times required for retreatment were recorded. ResultsReciproc produced significantly (P < .001) more debris than the other systems. ProTaper R and Mtwo R produced significantly (P < .001) more debris than D-Race and R-Endo. The Reciproc group required significantly (P < .001) less preparation time than the other groups. ConclusionsIn the retreatment of curved root canals, the Reciproc system extruded significantly more debris than the rotary retreatment NiTi systems. In addition, the ProTaper and Mtwo retreatment systems extruded significantly more debris than the R-Endo and D-Race systems. The Reciproc system was significantly faster than the rotary retreatment systems.

Evaluation of Radiopacity of Bulk-fill Flowable Composites Using Digital Radiography.

New flowable composites that may be bulk-filled in layers up to 4 mm are indicated as a base beneath posterior composite restorations. Sufficient radiopacity is one of the several important requirements such materials should meet. The aim of this study was to evaluate the radiopacity of bulk-fill flowable composites and to provide a comparison with conventional flowable composites using digital imaging. Ten standard specimens (5 mm in diameter, 1 mm in thickness) were prepared from each of four different bulk-fill flowable composites and nine different conventional flowable composites. Radiographs of the specimens were taken together with 1-mm-thick tooth slices and an aluminum step wedge using a digital imaging system. For the radiographic exposures, a storage phosphor plate and a dental x-ray unit at 70 kVp and 8 mA were used. The object-to-focus distance was 30 cm, and the exposure time was 0.2 seconds. The gray values of the materials were measured using the histogram function of the software available with the system, and radiopacity was calculated as the equivalent thickness of aluminum. The data were analyzed statistically (p<0.05). All of the tested bulk-fill flowable composites showed significantly higher radiopacity values in comparison with those of enamel, dentin, and most of the conventional flowable composites (p<0.05). Venus Bulk Fill (Heraeus Kulzer) provided the highest radiopacity value, whereas Arabesk Flow (Voco) showed the lowest. The order of the radiopacity values for the bulk-fill flowable composites was as follows: Venus Bulk Fill (Heraeus Kulzer) ≥ X-tra Base (Voco) > SDR (Dentsply DeTrey) ≥ Filtek Bulk Fill (3M ESPE). To conclude, the bulk-fill flowable restorative materials, which were tested in this study using digital radiography, met the minimum standard of radiopacity specified by the International Standards Organization.

Cuspal Displacement Induced by Bulk Fill Resin Composite Polymerization: Biomechanical Evaluation Using Fiber Bragg Grating Sensors.

Polymerization shrinkage is a major concern to the clinical success of direct composite resin restorations. The aim of this study was to compare the effect of polymerization shrinkage strain of two resin composites on cuspal movement based on the use of fiber Bragg grating (FBG) sensors. Twenty standardized Class II cavities prepared in upper third molars were allocated into two groups (n = 10). Restorations involved the bulk fill placement of conventional microhybrid resin composite (Esthet•X® HD, Dentsply DeTrey) (Group 1) or flowable “low-shrinkage” resin composite (SDR™, Dentsply DeTrey) (Group 2). Two FBG sensors were used per restoration for real-time measurement of cuspal linear deformation and temperature variation. Group comparisons were determined using ANCOVA (α = 0.05) considering temperature as the covariate. A statistically significant correlation between cuspal deflection, time, and material was observed (p < 0.01). Cuspal deflection reached 8.8 μm (0.23%) and 7.8 μm (0.20%) in Groups 1 and 2, respectively. When used with bulk fill technique, flowable resin composite SDR™ induced significantly less cuspal deflection than the conventional resin composite Esthet•X® HD (p = 0.015) and presented a smoother curve slope during the polymerization. FBG sensors appear to be a valid tool for accurate real-time monitoring of cuspal deformation.

In vitro evaluation of a newly produced resin-based endodontic sealer.

ObjectivesA variety of root canal sealers were recently launched to the market. This study evaluated physicochemical properties, biocompatibility, and sealing ability of a newly launched resin-based sealer (Dia-Proseal, Diadent) compared to the existing root canal sealers (AHplus, Dentsply DeTrey and ADseal, Metabiomed).Materials and MethodsThe physicochemical properties of the tested sealers including pH, solubility, dimensional change, and radiopacity were evaluated. Biocompatibility was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. For microleakage test, single-rooted teeth were instrumented, and obturated with gutta-percha and one of the sealers (n = 10). After immersion in 1% methylene blue solution for 2 weeks, the specimens were split longitudinally. Then, the maximum length of staining was measured. Statistical analysis was performed by one-way analysis of variance followed by Tukey test (p = 0.05).ResultsDia-Proseal showed the highest pH value among the tested sealers (p < 0.05). ADseal showed higher dimensional change compared to AHplus and Dia-Proseal (p < 0.05). The solubility values of AHplus and Dia-Proseal were similar, whereas ADseal had the lowest solubility value (p < 0.05). The flow values of sealer in increasing order were AHplus, DiaProseal, and ADseal (p < 0.05). The radiopacity of AHplus was higher than those of ADseal and Dia-Proseal (p < 0.05). The cell viability of the tested materials was statistically similar throughout the experimental period. There were no significant differences in microleakage values among the tested samples.ConclusionsThe present study indicates that Dia-Proseal has acceptable physicochemical properties, biocompatibility, and sealing ability.

“Comparative evaluation of dentinal penetration of three different endodontic sealers with and without smear layer removal” - Scanning electron microscopic study

Aim and Objectives: The aim of this study was to test the dentinal tubule penetration of mineral trioxide aggregate (MTA) Fillapex (Angelus, Londria, PR, Brazil), GuttaFlow® 2 sealer (Coltene/Whaledent) with standard sealer AH Plus (Dentsply Detrey, Konstanz, Germany) in instrumented root canals obturated by using cold lateral compaction techniques in either the presence or absence of the smear layer. Materials and Methods: Sixty extracted human mandibular premolars with a single root canal were used for this study. All teeth were prepared using F2 Pro Taper nickel–titanium rotary system. Teeth were randomly divided into three groups of 20 teeth each. GuttaFlow 2, MTA Fillapex and AH Plus were used as sealers in Group I, Group II, and Group III, respectively. Groups were divided into two subgroups in which either the smear layer was removed or retained. Removal of smear layer was achieved by continuous irrigation with 5.25% sodium hypochlorite and 2 ml of 17% ethylenediaminetetraacetic acid. The canals were dried and obturated using respective sealers by cold lateral compaction techniques. After storage at 37°C and 100% humidity for 14 days, the roots were then split into two halves using chisel and mallet. On each section, sealer penetration in the dentinal tubules at cervical, middle, and apical levels was examined by using scanning electron microscope. Results: Sealer penetration into the dentinal tubules was noticed in all groups. AH plus showed deeper penetration, followed by MTA Fillapex and GuttaFlow® 2. The penetration depth of the sealers at the cervical and middle third of root was significantly more than those at apical third. Conclusions: Within the parameters of the present study it was concluded, with the removal of smear layer AH plus sealer showed deeper penetration into the dentinal tubules at cervical and middle third of root compared with apical third.

Comparisons of the Retreatment Efficacy of Calcium Silicate and Epoxy Resin–based Sealers and Residual Sealer in Dentinal Tubules

IntroductionThe aim of this study was to evaluate the retreatment efficacy and amount of residual sealer in a single canal filled with either EndoSequence BC (Brasseler, Savannah, GA) or AH Plus (Dentsply DeTrey, Konstanz, Germany). MethodsCanal obturation with gutta-percha and sealer was performed in 28 human teeth using the continuous wave technique. Group 1 (n = 13) used AH Plus sealer, and group 2 (n = 15) used EndoSequence BC sealer. After 7 days, the root fillings were removed using Gates Glidden drills and a nickel-titanium rotary system. Retreatment time was measured in seconds. Canal cleanliness was examined by scanning electron microscopy. The remaining debris in the canal space and penetration into dentinal tubules were evaluated by confocal microscopy. Retreatment time was compared using the Student t test, and differences in sealer penetration and remaining debris between the groups were analyzed using the Mann-Whitney U test (P < .05). ResultsThere was no significant difference between the 2 groups in the amount of dentin penetration, amount of debris, or retreatment time. With respect to penetration depth, the AH Plus group showed a slightly higher percentage than the BC group, with a significant difference only in the portion 6 mm from the apex (P < .05). Scanning electron microscopic images showed significant debris remaining on canal walls in both groups, whereas canal patency in retreatment was achieved in every specimen. ConclusionsThe present study shows that EndoSequence BC sealer and AH Plus sealer have similar efficacy in dentin penetration and retreatment efficacy.

The effect of chloroform, orange oil and eucalyptol on root canal transportation in endodontic retreatment.

The purpose of the present study was to assess the effect of solvents on root canal transportation in endodontic retreatment. Sixty extracted human permanent mandibular first molars with curved root canals were selected. All of the root canals were prepared using Twisted File Adaptive instruments (SybronEndo, Orange, CA, USA) and filled with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) using the cold lateral compaction technique. The teeth were assigned to four retreatment groups as follows (n = 15): eucalyptol, chloroform, orange oil and control. The canals were scanned using cone-beam computed tomography scanning before and after instrumentation. The chloroform group showed a significantly higher mean transportation value than the orange oil and control groups at the 3 and 5 mm levels (P = 0.011 and P = 0.003, respectively). There was no significant difference among the orange oil, eucalyptol and control groups in terms of canal transportation (P > 0.61). The chloroform led to more canal transportation than the eucalyptol and orange oil during endodontic retreatment.

Evaluation of Effects on the Adhesion of Various Root Canal Sealers after Er:YAG Laser and Irrigants Are Used on the Dentin Surface

IntroductionThe aim of this study was to evaluate the bond strength of various root canal sealers after various irrigation solutions and Er:YAG laser irradiation were used on root canal dentin. MethodsOne hundred fifty freshly extracted human maxillary single-rooted teeth were used in this study. Teeth were sectioned transversally 4 mm below the cementoenamel junction. The root canal of each specimen was prepared using a tapered bur. Teeth were divided into 3 main groups by sealer (AH Plus Jet [Dentsply DeTrey, Konstanz, Germany], EndoSequence BC Sealer [Brasseler, Savannah, GA], and Real Seal [SybronEndo, Orange, CA]) and then divided into 5 subgroups by dentin treatment (distilled water, calcium hydroxide, sodium hypochlorite, EDTA, and Er:YAG laser). The specimens were placed immediately at 37°C and 100% humidity for 1 week. Then, the push-out test was applied. The maximum failure load was recorded in newtons and was used to calculate the push-out bond strength in MPa. Then, 3 random specimens from each group were examined under scanning electron microscopy. ResultsThe resin root canal sealers had higher push-out bond strength than the bioceramic sealer, and the differences were statistically significant (P < .05) except in the sodium hypochlorite groups. The EDTA and Er:YAG laser applications removed the smear layer and increased the bond strength. The highest adhesion was observed in EDTA groups when each sealer was evaluated in itself. ConclusionsThe bonding strength of root canal sealers is influenced by their properties and various dentin surface treatments. The scanning electron microscopic study showed that although the dentinal tubules were open, at the profile examination the sealers did not penetrate into the dentin canals in all specimens.

İKİ FARKLI KANAL PATININ FARKLI İRRİGASYON SOLÜSYONLARI KULLANILARAK PUSH-OUT YÖNTEMİ İLE DENTİNE BAĞLANMA DİRENÇLERİNİN DEĞERLENDİRİLMESİ

Amaç: Çalışmamızın amacı, kök kanalı irrigasyonu için farklı irrigasyon solüsyonlarının kullanılmasından sonra gütaperka ile farklı kanal patı kullanılarak yapılan kök kanal dolgusunun dentine ve gütaperkaya bağlanma dayanımının incelenmesidir. Gereç ve Yöntem: Çalışmamızda 70 adet çekilmiş üst keser ve kanin diş kullanıldı. Dişlerin kök kanal preparasyonları Mtwo ( VDW, Munich, Germany ) döner sistem eğeler kullanılarak 60.04 nolu eğeye kadar yapıldı. Dişler rastgele olarak her grupta 15 diş olacak şekilde 4 farklı gruba ayrıldı. Ayrıca 5’şer dişten oluşan 2 ayrı kontrol grubu oluşturuldu. Birinci (A) ve Üçüncü (C) gruplarda final irrigasyon olarak NaOCl ile MTAD solüsyonu sırası ile uygulandı. İkinci (B) ve dördüncü (D) gruplarda ise final irrigasyon olarak NaOCl ile EDTA uygulandı. Kontrol gruplarında ise irrigasyon solüsyonu olarak sadece NaOCl kullanıldı. Kök kanal dolguları A ve B gruplarında AH Plus ( Dentsply DeTrey, Konstanz, Germany ) kanal patı ve gütaperka, C ve D gruplarında ise Endorez ( Ultradent, South Jordan, USA ) kanal patı ve gütaperka kullanılarak tek kon yöntemiyle yapıldı. Kontrol gruplarından E grubunda kök kanal dolgusu için AH Plus kanal patı ve gütaperka, F grubunda ise Endorez kanal patı ve gütaperka kullanılarak tamamlandı. Kök kanal dolguları tamamlandıktan sonra dişler nemli ortamda bir hafta kadar bekletildikten sonra dişlerin koronal ve orta üçlü kısmından 3mm boyutunda horizontal kesitler alınarak farklı irrigasyon solüsyonu uygulamasının, farklı kanal patlarının dentin duvarına ve gütaperkaya bağlanma kuvvetlerine etkisi push-out yöntemiyle değerlendirildi. Elde edilen verilerin istatistiksel analizleri one way Anova Tukey-Kramer çok yönlü karşılaştırmalı testi kullanılarak yapıldı. Bulgular: Çalışmanın sonucunda elde edilen verilerin ortalama değerleri ve standart sapmaları; MTAD-AH Plus (1.13±0.18 a ), EDTA-AH Plus (1.10±0.26 a ), NaOCl-AH Plus (0.77±0.19 c ), MTAD-Endorez (0.99±0.20 b ), EDTA-Endorez (1.02±0.21 b ) ve NaOCl-Endorez (0.78±0.23 c ) MPa olarak bulundu. İstatistiksel olarak gruplar arasında anlamlı farklılık gözlendi. En yüksek bağlanma direnci MTAD irrigasyon solüsyonu kullanılarak AH Plus kanal patı ile yapılan kanal dolgusu sonrası elde edildi. Sonuç: Bu çalışmada, kök kanalının final irrigasyonunda, irrigasyon solüsyonu olarak NaOCl ile MTAD kullanılmasının ve kanal dolgusu işleminde ise uygun bir gütaperka ile AH Plus kanal patının kullanılmasının daha etkili olduğu sonucu bulunmuştur.

FİBER POST SİMANTASYONUNDA KULLANILAN SELF-ADEZİV REZİN SİMANLARIN MİKROSIZINTILARININ KARŞILAŞTIRILMASI

Aim: The aim of this study was to compare the microleakage of four self-adhesive resin cements used for fiber post cementation with fluid filtration method. Material and Method: In the study, 50 upper human canine teeth extracted for periodontal reasons were used. The root lengths of the teeth were mesured and standardized. Root canals were enlarged with rotary instruments (Protaper, Dentsply Maillefer, Ballaquies, Switzerland) and filling was achieved using lateral compaction technique. The specimens were randomly assigned to 5 groups (n=10). The fiber post (Exacto Glass Fiber posts, Angelus Industria de Produtos Odontologicos S/A, Londrina-PR-Brasil) cementations are completed with the fallowing materials: Variolink II Professional Pack (Ivoclar Vivadent, Liechtenstein) (Control), G-Cem Automix (GC, Tokyo, Japan), Panavia SA Cement (Kuraray, Okayama, Japan), Smart Cem 2 (Dentsply DeTrey GmbH, Konstanz, Germany) and Rely X U200 (3M ESPE, Neuss, Germany). The measurement of microleakage was performed at 2nd, 4th, 6th and 8th minutes. The data was analyzed by ANOVA and Tukey tests (p<0.05). Results: The best results were obtained in Rely X U200 and Panavia SA Cement groups, while the most leakage was seen in G-Cem Automix and Smart Cem 2 groups (p<0,05). There was statistically significant difference between Rely X U200 and Panavia SA Cement groups compared to the control group (p<0,05). The control group was found to have statistically less microleakage than G-Cem Automix and Smart Cem 2 groups (p<0,05). Conclusion: From the point of microleakage, some self adhesive resin cements used for fiber post cementation were found to be more reliable than the control group material

Two-year clinical performance of a two-step etch-and-rinse adhesive in non-carious cervical lesions: Influence of subject's age and dentin etching time.

The aim of this study was to evaluate the influence of the subject's age and dentin etching time on the clinical performance of a two-step etch-and-rinse adhesive in class V non-carious cervical lesions (NCCLs). Forty patients with NCCLs (classified as degrees 2 and 3 of dentin sclerosis) were enrolled in this study. The lesions were selected and assigned into two groups (n = 70/group) according to the subject's age: (G1) between 21-35 years old and (G2) between 40-54 years old. Each group was randomly divided into two subgroups (n = 35/group) according to dentin etching time using recommended application time (15 s) and an extended application time (30 s). A total of 140 restorations with XP Bond (Dentsply DeTrey, Germany) were placed. The composite resin Esthet X (Dentsply) was placed incrementally. All restorations were evaluated using the modified USPHS criteria. Data was analyzed by the McNemar and chi-square tests (p < 0.05). At the end of 2 years, 132 restorations (94.2% recall rate) were evaluated. The 24-month retention rates (%) were 93.5 for G1(15), 97.1 for G1(30), 93.9 for G2(15), and 97.0 for G2(30). There were no statistical differences in the retention rates in each recall period among groups. For the selected age groups, neither the subject's age nor the etching time had any influence on the clinical performance of XP Bond adhesive in NCCLs over a 24-month period. The clinical effectiveness of the XP Bond was excellent after 2 years of clinical service. Long-term clinical evaluations are necessary to confirm this finding.

The Effect of Obturation Technique on the Push-out Bond Strength of Calcium Silicate Sealers

IntroductionCalcium silicate–based sealers are known to have excellent sealing ability and bioactivities. They are typically recommended to be used in a single-cone (SC) technique. No studies have evaluated the effects of the thermoplastic obturation technique on the dentin interface of these sealers. The purpose of this study was to evaluate the push-out bond strengths of MTA Plus Sealer (Avalon Biomed Inc, Bradenton, FL) and EndoSequence BC Sealer (BC; Brasseler USA, Savannah, GA) when they were used in a thermoplastic technique. MethodsFifty single-rooted human extracted teeth were randomly divided into 5 groups (n = 10), instrumented, and obturated with the SC technique or continuous wave (CW) technique: group 1, BC-SC; group 2, BC-CW; group 3, MTA Plus–SC; group 4, MTA Plus–CW; and group 5, AH Plus (Dentsply DeTrey, Konstanz, Germany)–CW. The roots were sectioned into 1.0-mm-thick slices, and bond strengths were measured using a standardized push-out test. The mode of failure was determined by visual inspection under magnification. ResultsThe MTA Plus–CW had statistically significant lower bond strengths than all other groups. The BC-SC group had statistically higher bond strengths than the MTA Plus–SC and AH Plus–CW groups. No significant differences were seen among the other groups. Modes of failure were predominately cohesive or mixed except for group 4 (ie, MTA Plus–CW) in which nearly half the specimens had no visible sealer. ConclusionsBC and MTA Plus sealer showed favorable bond strengths when used in an SC technique. The CW obturation technique decreased the bond strengths of these sealers.

The effect of different drinks on the color stability of different restorative materials after one month

ObjectivesThe aim of this study was to evaluate the effect of three different drinks on the color parameters of four different restorative materials.Materials and MethodsThree different composites (Filtek Ultimate Universal Restorative, Filtek Ultimate Flowable, and Filtek Silorane, 3M ESPE) and a polyacid-modified composite resin material (Dyract XP, Dentsply DeTrey GmbH) were evaluated. Eighty-four disc-shaped specimens of 8 mm in diameter and 2 mm in thickness were prepared (n = 21 each). Color coordinates (L*a*b*, ΔL*, Δa*, Δb*, and ΔE*) were measured using a VİTA Easyshade Compact (VİTA Zahnfabrik) after 24 hr of storage (baseline) and after 30 day of storage in three different beverages of black tea, Coca cola, or water (control) (n = 7). In each beverage, the specimens were stored three times a day, one hr each, for 30 day. The color changes (ΔE) were calculated and were analyzed by Kruskal-Wallis and Dunn multiple comparison test.ResultsThe color difference (ΔE*) of the resin materials ranged between 1.31 and 15.28 after 30 day of immersion in the staining solutions. Dyract XP in Coca cola (15.28 ± 2.61) and black tea (12.22 ± 2.73) showed the highest mean ΔE* value after 30 day, followed by Filtek Ultimate Universal Restorative (5.99 ± 1.25) and Filtek Ultimate Flowable (4.71 ± 1.40) in black tea (p < 0.05).ConclusionsThe compomers displayed unacceptable color changes at the end of 30 day in all beverages. Among resin composites, the silorane based composite exhibited relatively good color stability than the others. Filtek Ultimate Universal Restorative and Filtek Flowable showed similar color changes in all beverages.