Obturation ability of root canal treatment materials are one of the factors that affect the prognosis of root canal treatment with essence of complete closure of the root canal. Cold lateral condensation is one of the most common techniques used for endodontic therapy which sealer acts as sealing and bonding agent between dentin and gutta-percha. The aims of the study are to examine and compare the volumetric shrinkage of the three most common endodontic sealers in Sweden categorized by their chemical composition. Our hypothesis is that there is no difference between these sealers regarding shrinkage. Epoxy-amine resin based sealer (AH Plus Jet), zinc oxide eugenol based sealer (Tubli-Seal EWT) and calcium hydroxide based (Apexit Plus) have been compared in this study, which are categorized into three major different chemical compositions. A video imaging technique device, AcuVol, has been used to register volumetric shrinkage of these sealers. Registration of sealers volumetric shrinkage by AcuVol occurred two times for each sealer during a 48 hr period. Mean volumetric shrinkage after 48 hr determined to 6.43 % for epoxy-amine resin based sealer (AH Plus Jet), 6.72 % for zinc oxide eugenol based sealer (Tubli-Seal EWT) and 1.63 % for calcium hydroxide based sealer (Apexit Plus). Based on this study, it could not be possible to recommend a sealer in terms of volume shrinkage perspective and determine which sealer is best. There are other parameters of sealer than shrinkage that can affect adequately root canal obturation we should consider.

Diversion methods are routinely used in both matrix acidizing and fracturing stimulation treatments. In this study, we focus on one of the classical mechanical diversion methods, ball sealers. Ball sealer diversion is used in cased and perforated wells to divert stimulation fluids by temporarily blocking perforation holes in the casing with rubber-coated balls. This diversion method can be very effective, but there is no general methodology to design ball sealer diversion, or to evaluate its effectiveness from the treating rate and pressure record. Experimental data from an extensive series of full-scale flow experiments conducted by BP were analyzed. One field treatment was analyzed and compared, and a similar trend in seating efficiency was observed. Then, we developed an empirical correlation on the basis of BP experimental data. The correlation enables us to estimate how many ball sealers seat on the perforations. By incorporating this correlation into an acid placement model, we can estimate wormhole penetrations along the wellbore with time. We developed a computer program and studied one hypothetical case to show the usefulness of the ball sealer diversion model.

Aim To evaluate efficacy of XP-3D and TRUShape rotary retreatment system for gutta-percha (GP) removal from root canals. Methodology Root canals of 40 extracted human single rooted teeth were prepared with ProTaper gold rotary system and obturated with hydraulic condensation technique with BC sealer (n=20) or multiple wave technique with ZOE sealer (n=20). Teeth were evaluated with Micro CT and then divided into four groups and in all groups, GP first removed with Gates Glidden drills and patency achieved by K stainless steel files (Kerr) files with chloroform as a solvent. Further canal repreparation accomplished: group A (n=10, BC sealer/hydraulic condensation technique) – GP removal with the XP-3D shaper and finisher; group B (n=10, BC sealer/hydraulic condensation technique) –GP removal with the TRUshape; group C (n=10, ZOE sealer/multiple wave technique) – GP removal with the XP-3D shaper and finisher; group D (n=10, ZOE sealer/multiple wave technique) – GP removal with the TRUshape. Operating time was recorded. Teeth were evaluated with micro-CT of the area of remaining GP/sealer in bucco-lingual and mesial–distal directions. Two-way ANOVA Statistical analysis was performed. Results There was a statistically significant difference among the groups regarding sealer removal (P<0.05), the retreatment of samples with ZOE was more effective than BC Sealer. No significant difference was observed between retreatment rotary systems of group C and D (ZOE Sealers). The volume of remaining obturation material was significantly less in group B than group A (BC Sealers). Mean operating time for group A was 6.71 min, which was significantly higher (P <0.05) than group B (3.78 min), group C (3.76 min) and group D (3.10 min). Conclusion BC sealer has much lower removal efficiency than ZOE sealer regardless of the type of file that is used to remove. TRUshape was the most efficient in gutta-percha removal from the canals when obturated with BC Sealer. The fastest technique to remove gutta-percha and the shortest time to reach working length was observed in group D (n=10, ZOE sealer/multiple wave technique) – GP removal with the TRUshape.

Bei der vorliegenden Arbeit handelt es sich um eine klinische und radiologische Nachuntersuchung von insgesamt 114 Patientinnen und Patienten, die zwischen 2009 und 2012 in der Poliklinik für Zahnerhaltung und Parodontologie der Universität Würzburg von approbierten Zahnärztinnen und Zahnärzten endodontisch behandelt wurden. Dabei kamen drei verschiedene Obturationsmethoden zum Einsatz. 1. Single-Cone-Technik mit Guttapercha und AH Plus® (SCGP) 2. Single-Cone-Technik mit Guttapercha und GuttaFlow® (SCGF) 3. Adhäsive Obturation in Continuous-Wave-Technik mit Resilon® (CWR) Die Erhebung der Ausgangsvariablen (zum Behandlungszeitpunkt) erfolgte retrospektiv unter Zuhilfenahme der klinischen und radiologischen Dokumentation. Die Reevaluation des periapikalen Zustands der Zähne und die Erhebung weiterer klinischer Parameter erfolgte im Rahmen eines aktiven Patientenrecalls nach durchschnittlich 6,3 Jahren. Dabei wurden mit möglichst hoher Standardisierung postoperative Einzelzahnaufnah-men angefertigt. Diese wurden anhand der PAI-Klassifikation ausgewertet, um den pe-riapikalen Zustand der Zähne vor und nach Therapie zu bestimmen. PAI-Werte von 1 und 2 galten als Behandlungserfolg, Grad 3 bis 5 als Misserfolg. Im Hinblick auf die de-finierten Arbeitshypothesen wurden die Erfolgsraten innerhalb der Kohorten miteinander verglichen. Das vorrangige Ziel der hier vorliegenden Arbeit war, zu untersuchen, ob der endodontische Behandlungserfolg abhängig von der jeweiligen Obturationsmethode ist und ob technikspezifische Unterschiede sich einerseits auf die Qualität der Obturation und andererseits auf das Auftreten möglicher Komplikationen, wie der periapikalen Extrusion von Wurzelfüllmaterial, auswirken. Ferner sollten diese Aspekte neben weite-ren zahn- und patientenbezogenen Variablen bezüglich ihres Einflusses auf die Erfolgs-rate der endodontischen Therapie analysiert werden. Es konnten keine signifikanten Unterschiede der endodontischen Erfolgsraten zwischen den hier untersuchten Obturationsmethoden ermittelt werden (p = ,16). In der SCGP-Kohorte lag die Erfolgsrate bei 85 % (34/40) verglichen mit 68,8 % (44/64) für CWR und 80 % (8/10) für SCGF. Die Homogenität der Obturation (p = ,2) und die Extrusion von Wurzelfüllmaterial in das periapikale Gewebe (p = ,93) zeigten keine Abhängigkeit von der gewählten Obturationstechnik. Die Länge der Wurzelkanalfüllung hingegen unter-schied sich signifikant zwischen den Kohorten (p = ,04*). Die Obturation mittels SCGP-Technik erzielte den höchsten Anteil adäquater Wurzelkanalfüllungen (92,5 %, 37/40) gegenüber SCGF (80 %, 8/10) und CWR (71,88 %, 46/64). Die CWR-Methode zeigte mit 18,8 % (12/64) den höchsten Anteil an unterfüllten Obturationen (SCGP: 7,5 %, 3/40; SCGF: 0 %). Unabhängig von der Obturationsmethodik zeigte sich der endodontische Behandlungs-erfolg im Allgemeinen unbeeinflusst von der Qualität der Wurzelkanalfüllungen. Die Va-riablen Obturationslänge (p = ,12) und -homogenität (p = ,11) sowie die Extrusion von Wurzelfüllmaterial in die periapikale Region (p = 1,00) zeigten keinen signifikanten Ein-fluss auf die Erfolgsrate. Das Durchschnittsalter im Patientenkollektiv betrug 60 Jahre mit einer tendenziellen Überrepräsentation weiblicher Probandinnen (60,5 %, 69/114). 73 % (81/111, 3 Mis-sings) der Studienteilnehmer/-innen wurden ab einem PSI-Grad von 3 als parodontal erkrankt eingestuft und 23,7 % (27/114) zeigten eine positive Raucheranamnese. Der BMI betrug im Durchschnitt 26,3 kg/m2. 42,3 % (47/111, 3 Missings) der Studienteil-nehmer/-innen wurden anhand der Einnahme von Medikamenten zur Therapie bzw. Prävention von kardiovaskulären Erkrankungen und/oder oraler Antidiabetika als chro-nisch erkrankt klassifiziert (chronic disease medication, CDM). Das Recallintervall be-trug durchschnittlich 6,3 Jahre mit einem Minimum von 4,7 und einem Maximum von 8,7 Jahren. Die patientenbezogenen Variablen Alter (p = ,45), Geschlecht (p = ,67), Pa-rodontitis (p = ,08), BMI (p = ,58), CDM (p = ,19), Recallintervall (p = ,08) und Rauchen (p = ,34) zeigten keinen signifikanten Einfluss auf den endodontischen Behandlungser-folg. Unter den zahnbezogenen Variablen beeinflusste lediglich der präoperative apikale Sta-tus den endodontischen Erfolg signifikant (p = ,007*). Zähne mit präoperativer apikaler Läsion zeigten eine Erfolgsrate von 66,2 % (47/71) gegenüber 90,7 % (n = 39/43) bei Fällen ohne apikale Läsion. Die Misserfolgswahrscheinlichkeit bei Vorliegen einer präoperativen Läsion war um den Faktor 4,98 erhöht (OR = 4,98, 95 % KI: 1.60, 15,57, p = ,006*). Zwischen Kompositfüllungen, Teilkronen, Vollkronen, Teleskopkronen und Brückenversorgungen konnten keine relevanten Unterschiede in den Erfolgsraten er-mittelt werden (p = ,29). Gleiches galt für adäquate (76,6 %, 82/107) und inadäquate (57,1 %, 4/7) Restaurationen (p = ,36). Ebenso zeigten die Erfolgsraten von Wurzelka-nalrevisionen (70,5 %, 31/44) und Primärbehandlungen (78,6 %, 55/70) keine signifikan-ten Abweichungen voneinander (p = ,45). Molaren waren im Studienkollektiv mit 56,1 % (64/114) gegenüber Prämolaren und Frontzähnen mit je 21,9 % (25/114) überrepräsen-tiert. Der Zahntyp (p = ,07) und die Ausgangsdiagnose (p = ,22) stellten keine relevanten Einflussfaktoren des endodontischen Erfolgs dar. / This work is a clinical and radiological follow-up examination of a total of 114 patients who underwent endodontic treatment between 2009 and 2012 in the Department of Conservative Dentistry and Periodontology at the University of Würzburg by licensed dentists. Three different obturation methods were used. 1. Single Cone Technique with gutta-percha and AH Plus® (SCGP) 2. Single cone technique with gutta-percha and GuttaFlow® (SCGF) 3. Adhesive Obturation in Continuous Wave Technique with Resilon® (CWR) The initial variables (at the time of treatment) were collected retrospectively with the help of clinical and radiological documentation. The re-evaluation of the periapical condition of the teeth and the collection of further clinical parameters was carried out as part of an active patient recall after an average of 6.3 years. Postoperative single-tooth radiographs were made with the highest possible level of standardization. These were evaluated using the PAI classification to determine the periapical condition of the teeth before and after therapy. PAI values of 1 and 2 were considered treatment success, grades 3 to 5 as failure. With regard to the defined working hypotheses, the success rates within the cohorts were compared. The primary goal of the present work was to investigate whether the endodontic treatment success is dependent on the obturation method and whether technique-specific differences affect the quality of the obturation on the one hand and the occurrence of possible complications such as the periapical extrusion of root filling material on the other. Furthermore, these aspects should be analyzed in addition to other tooth- and patient-related variables with regard to their influence on the success rate of endodontic therapy. No significant differences in endodontic success rates could be determined between the obturation methods examined here (p = .16). In the SCGP cohort, the success rate was 85% (34/40) compared to 68.8% (44/64) for CWR and 80% (8/10) for SCGF. The homogeneity of the obturation (p = .2) and the extrusion of root filling material into the periapical tissue (p = .93) showed no dependence on the chosen obturation technique. The length of the root canal filling, on the other hand, differed significantly between the cohorts (p = .04*). Obturation using the SCGP technique achieved the highest proportion of adequate root canal fillings (92.5%, 37/40) versus SCGF (80%, 8/10) and CWR (71.88%, 46/64). The CWR method showed the highest proportion of underfilled obturations with 18.8% (12/64) (SCGP: 7.5%, 3/40; SCGF: 0%). Regardless of the obturation method, the endodontic treatment success was generally unaffected by the quality of the root canal fillings. The variable obturation length (p = .12) and homogeneity (p = .11) as well as the extrusion of root filling material into the periapical region (p = 1.00) showed no significant influence on the success rate.

AIM:  to evaluate the flow, working time, setting time, film thickness and solubility of a novel root canal sealers (MTA Fillapex) in comparison with a zinc oxide-eugenol– based sealer (Tubli-Seal), epoxy resin-based sealers (AH 26), a calcium hydroxide-based sealer (Apexit Plus), and a silicone-based sealer (ReokkoSeal Automix). MATERIALS AND METHODS: ISO 6876/20012 specifications were followed except for the solubility test. Solubility was measured by the amount of material extracted from the specimens left in water over 24 hr period. Film thickness was measured as the distance between weighted glass slides containing a standard quantity of sealer. Flow was assessed by rate of sealer extrusion through a standard bore diameter, after unit time. Working time was taken as the point at which flow rate was reduced by 10%. The indentation test using a modified Gilmore needle was employed to investigate the setting times. RESULTS: ReokkoSeal Automix and MTA Fillapex were the least soluble, whilst Tubli- Seal was the most unstable in water. Also, Tubli-Seal had the highest film thickness. All sealers showed comparable flow rates. The working time varied from 30 min for MTA Fillapex to 4 hr for AH 26. The range of setting times recorded was from 64 min for Tubli-Seal Xpress to more than 5 hr for AH 26. CONCLUSIONS: MTA Fillapex and RoekoSeal Automix showed the greatest stability in Solution. The film thickness values in increasing order were: AH26 < Apexit plus = RoekoSeal Automix < MTA Fillapex < Tubli-Seal Xpress. The flow rates for Tubli-Seal xpress, AH26, and RoekoSeal Automix are statistically similar, while Apexit plus and MTA Fillapex are statistically similar. The working times for all sealers were greater than 30 min. AH26 did not set when incubated in volumes sufficient to fill the test matrices. / 2018-09-28T00:00:00Z

Magister Scientiae Dentium - MSc(Dent) / Statement of problem: Although bioceramic endodontic sealer cements offer various advantages over conventional zinc oxide-based and resin-based cements, questions have been raised about the ability to retreat root canals that have been sealed using these cements. Aims and Objectives: The aim of the study was to determine the retreatability of root canals sealed using a bioceramic calcium silicate-based sealer cement. The objectives were to determine the possibility of achieving working length and apical patency when obturation is done with the master GP placed at working length and when it is short by 3mm. The time it took to achieve these parameters when it was possible to achieve them was also determined. The role of XP Endo Finisher R, a supplementary retreatment file, in achieving working length and apical patency was also to be evaluated. However, this latter aspect was eliminated after the pilot study, when it was found not to have an effect in regaining working length and apical patency.

Introduction: The primary reason for endodontic treatment failure is microbial infection inside the root canal system by different microbes including Enterococcus faecalis. Endodontic sealers with Chitosan (CS), a compound with antimicrobial effects, can decrease the growth of microorganisms and potentially prevent failure. Purpose: The aim of this study was to assess the antimicrobial activity ex-vivo and flowability of calcium silicate root canal sealers with added CS fillers. Materials and methods: EndoSequence (BC) sealer was mixed with CS fillers in two different concentrations (5% and 10%wt). Flowability was analyzed according to ISO-6876. The antibacterial assessment was conducted using an ex-vivo model. Extracted single-rooted teeth were infected with E. faecalis for 7 days. Follow the root canal treatment, the sealers (BC, BC+CS-5%, BC+CS-10%, N=6) were used for obturation and re-incubated in the bioreactor for 24 hours. Untreated teeth were used as positive control. Cell viability (CFU/mL) and fluorescence microscopy were used to determine the number of bacteria at the bonded interface. ANOVA was used for statistical analysis. Results: Addition of CS fillers into BC resulted in a significant decrease in flowability (BC:22mm, BC+CS-5%:19mm, BC+CS-10%:16mm). All evaluated sealers showed antibacterial activity. The addition of CS significantly reduced the viable cells (log(CFU/mL)) (CS-5%:5.3, CS-10%:4.6) compared with the BC (5.9) and positive control (7.2). Fluorescence analysis showed that CS-Sealers group had an increased number of dead cells (CS-10%:77.3%, CS-5%:64.4%) compared with the BC-Sealer (37.9%) and positive control (23.3%). Conclusion: Endodontic sealers with added CS enhanced antimicrobial effects of the sealer. However, adding more than 5% of CS affects the flow properties of the sealer. / Oral Biology

Indiana University-Purdue University Indianapolis (IUPUI) / Background: Numerous studies have reported the effect of long-term use of calcium hydroxide Ca(OH)2 to dentin. Nevertheless, there is little information available about the effect of Ca(OH)2 on wettability to the dentin. Objective: To investigate the effect of Ca(OH)2 application on dentin for two and four weeks on the wettability of two root canal sealers. Methods: Polished caries-free human dentin discs (n = 156) were allocated into 12 groups; G1 and G3 had two weeks’ treatment, G4 and G6, four weeks treatment. G1 and 101 G4 were treated with sterile water. G2, G3, G5 and G6 were treated with Ca(OH)2. G1, G3, G4, and G6 were irrigated with 6.0-percent NaOCl and 17-percent EDTA while G2, and G5 were irrigated with sterile water. Then, contact angles between Tubli-Seal and the treated dentin surfaces were measured. G7 and G12 were treated in the same fashion but were treated with BC sealer. Surface morphology evaluation of G1 and G6 was carried out by scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX). Statistics were performed using three-way ANOVA and pair-wise comparisons between groups (α = 0.05). Results: Tubli-Seal (G1 through G6) had significantly smaller values for contact angles than BC sealer (G7 through G12) (p < 0.05). For the Tubli-Seal groups (G1 through G6), G4 had the highest mean of contact angles at 104.9 ± 1.9°, whereas G5 presented the lowest mean of contact angles at 85.4 ± 15.1. For the BC sealer groups (G7 through G12), G10 had the highest mean of contact angles at 145.4 ± 1.3°, while G11 demonstrated the lowest mean of contact angles at 130.2 ± 2.6°. Groups with Ca(OH)2 treatment with water irrigation (G2, 5, 11) had significantly lower contact angle than groups with Ca(OH)2 with chemical irrigation (G3, 6, 12) (p < 0.05), except G8, 9. According to SEM and EDX, water irrigation solution showed higher remaining Ca(OH)2 than irrigation with the chemical solution while Ca(OH)2 with chemical irrigation 102 demonstrated no Ca(OH)2 remaining after irrigation, similar to the surface of the control group. Conclusion: Within the limitations of this study, Tubli-seal has better wettability on dentin than BC sealer. Remaining calcium hydroxide demonstrated a trend toward decreased contact angle between dentin and root canal sealers. Moreover, two-minute irrigation with 6-percent NaOCl and 17-percent EDTA can remove calcium hydroxide from polished dentin surfaces.

The purpose of this study was to evaluate effect of final rinse of ethanol on bond strength in teeth obturated with Gutta Percha (GP)/AH Plus® or Resilon/Epiphany®SE™. Thirty-two extracted human anterior teeth were shaped to size 30, 0.06 taper and subjected to an identical irrigation protocol. Specimens were randomly divided into eight groups according to final irrigating solution (saline, 70%, 95%, 100% ethanol) and obturation material. Two millimeter thick slices were obtained by sectioning each obturated root. Bond strength was determined using micropush-out assay. Data was analyzed using Student’s t-test. Obturation with GP/AH Plus® formed a statistically significant stronger bond than Resilon/Epiphany®SE™. A final rinse with ethanol (irrespective of ethanol concentration) did not enhance push-out bond strength with GP/AH Plus®. Push-out bond strength of Resilon/Epiphany®SE™ decreases with increased ethanol concentration with Resilon/Epiphany®SE™. Among Resilon/Epiphany®SE™ groups, 70% ethanol resulted in strongest bond strength.

The purpose of this study was to evaluate the effect of a final rinse of ethanol on depth of sealer penetration in teeth obturated with Gutta Percha (GP)/AH-Plus® (Dentsply, De Trey GmbH, Konstanz, Germany) or Resilon/Epiphany® SE™ (Pentron Clinical Technologies, LLC, Wallingford, CT). Extracted human anterior teeth (n= 32) were shaped to size 30, 0.06 taper using nickel-titanium rotary files and subjected to an identical irrigation protocol. Specimens were randomly divided into eight groups according to final irrigating solution (saline, 70%, 95%, or 100% ethanol) and obturation material (GP/AH-Plus® or Resilon/EpiphanyÒ SE™). A 2mm thick slice was obtained by sectioning each obturated root at 3mm and 5mm from the anatomic apex. Specimens were cleared and assessed using scanning electron microscopy (SEM). Sealer penetration was observed at different magnifications when using GP/AH Plus® across all final rinse concentrations. Among Resilon/Epiphany® SE™ groups, no sealer penetration was evident under SEM. Conclusions: 1) GP/AH-Plus® showed evidence of sealer penetration, however, Resilon/Epiphany® SE™ did not show evidence of sealer penetration at both the dentin and sealer interface. 2) A final rinse with any concentration of ethanol prior to obturation does not improve sealer penetration with GP/AH-Plus® groups. 3). Resilon/Epiphany® SE™ bond can be dislodged at either the interface of sealer and Resilon or dentin and Resilon.