Seal Of Root Canal Fillings Research Articles

The effects of pressure in vitro on three methods of root canal obturation.

The seal of root canal fillings depends on the anatomy of the root canal system and on the properties of filling materials and their bond to the walls of the root canal. Alterations in pressure may influence these properties. The current study investigated and compared microleakage in a tapered single-cone method versus lateral and vertical condensation after diving simulation. One hundred and thirty five extracted single-rooted teeth were used. Following instrumentation and irrigation to #30.06 Mtwo rotary system, obturations were performed in three groups of 45 teeth: Group 1, tapered single-cone with Endoseal MTA sealer; Group 2, lateral condensation with AH26 sealer; Group 3, vertical condensation with AH26 sealer. Then all specimens were divided into three groups and incubated at ambient room pressure (101.3 kPa), 203 kPa or 304 kPa for 120 minutes respectively 20 times over one month to simulate diving conditions. Microleakage quantitative analysis was recorded by using a 2% Methylene blue dye for 24 hours. The amounts of microleakage increased with increasing pressure in all obturation groups; however, the differences were not statistically significant (P > 0.05). At all three pressures, the least microleakage was recorded in Group 3, vertical condensation. Although the differences between vertical condensation, lateral condensation, and tapered single-cone methods were statistically significant (P < 0.001), the vertical condensation and lateral condensation groups did not differ from each other (P > 0.05). Vertical condensation may be the best technique, based on sealing ability, for people who frequently experience pressure alterations.

Secondary protective seal of root canal fillings performed under simulated clinical conditions

Objective: This study evaluated sealing properties of root canal fillings with an additional composite barrier. The null hypothesis tested was that different sealers and different methods of sealer removal did not influence microleakage. Material and methods: Eighty extracted human molars with fully mature apices had root canal prepared to size 60 taper .02 and divided into eight groups: three experimental groups for each sealer and negative/positive control (n = 10 each). Teeth of experimental groups were mounted into the molar region of a training puppet to simulate clinical conditions. Root canals were filled with AH Plus or GuttaFlow and gutta-percha. Excess sealer was removed with: ethanol-moistened foam pellet only, additional preparation with a water-cooled diamond bur or additional etch-and-rinse procedure (37% phosphoric acid gel). All procedures were carried out until clean as judged by the naked eye. In all groups except the positive control Syntac was applied to the access cavity. Tetric flow was applied in two increments of 1 mm each. A dye penetration test was carried out by centrifugation for 3 min at 30 G within 5% methylene blue dye. Statistical evaluation was carried out with PASW 18.0 (α = 0.05). Results: Although the two sealers had different chemical composition, sealer exhibited no influence on the results, whereas technique of sealer removal did (Two-way-ANOVA, p &lt; 0.001). Groups with “foam pellet” or “bur preparation” showed significantly more leakage than groups with “etch-and rinse” (SNK, p &lt; 0.05). Conclusion:Applying an etch-and-rinse procedure prior to Syntac may be beneficial for the adhesive seal over root canal fillings.

An evaluation of the influence of passive ultrasonic irrigation on the seal of root canal fillings

To evaluate the influence of passive ultrasonic irrigation (PUI) on the seal of root canal fillings. A total of 40 mandibular premolars were distributed equally into two groups and the root canals were cleaned and shaped; they were then filled with gutta-percha and AH26 (sealer) using the warm vertical compaction technique with the System B (Analytic Technology, Redmond, WA, USA) device. In one group PUI was applied, after completion of instrumentation and hand-irrigation. In the other group, PUI was not applied. Thereafter, leakage of glucose was evaluated by measuring its concentration once a week for a total period of 56 days using a glucose penetration model. Differences between the groups in terms of glucose concentrations were statistically analysed with the Mann-Whitney test; the level of significance was set at P=0.05. After the first month the root fillings in teeth where PUI had been used, sealed the root canal significantly better than in teeth where no PUI had been used (P=0.017). Root fillings sealed the root canal better when PUI had been used.

Influence of Moisture on the Apical Seal of Root Canal Fillings With Five Different Types of Sealer

The aim of this study was to evaluate the influence of moisture on apical leakage using five different types of sealer. There were 120 single-rooted teeth instrumented to .02/#60 and randomly assigned to 10 experimental groups, one control group (AH Plus, lateral condensation) ( n = 10) or positive/negative controls ( n = 5). Before obturation teeth were dried thoroughly, followed by recontamination with moisture in a wet chamber (moist groups; 37°C for 7 days). The teeth of the experimental groups (a, dry; b, moist) were obturated with sealer (groups 1, AH Plus; 2, Apexit; 3, Ketac-Endo; 4, RoekoSeal; 5, Tubli-Seal) and a single gutta-percha cone .02/#55. Teeth were centrifuged (30 × g for 3 minutes) in 5% methylene blue. Linear dye penetration was measured under a stereomicroscope. Moisture led to less microleakage for Apexit, RoekoSeal, and Tubli-Seal and higher values for AH Plus and Ketac-Endo. Multifactorial ANOVA displayed a significant dependence of leakage on sealer (p < 0.001) and the combination sealer or moisture (p < 0.01). It depends on the sealer type in which way moisture affects the apical seal.

Microbial Leakage of Cavit, IRM, and Temp Bond in Post-prepared Root Canals Using Two Methods of Gutta-percha Removal: An In Vitro Study

The aim of this study was to evaluate the integrity of the coronal seal of Temp-Bond and compare it to Cavit and IRM after post space preparation using S. faecalis as a microbial tracer. In addition, the affect of two methods of gutta percha removal on the apical seal of root canal fillings was also evaluated. Forty extracted human single rooted teeth were prepared chemomechanically and obturated with gutta percha and AH26 sealer cement using the lateral cold condensation technique to a standardized working length of 15 mm. About 10 mm of the coronal gutta-percha was removed with either Peeso-reamer or a hot plugger. The roots were divided into three experimental groups of 10 roots and a control group. Each experimental group was subdivided equally into two groups of 15 each according to the method of post space preparation. Cavit, IRM, and Temp-Bond were used to seal the access opening. Each root was fixed in a cuvette containing Tryptic Soya Broth which, covered 2 mm of the root apex. Bacterial suspension was introduced through pipette. Fresh bacterial suspension was added every week, and the system was monitored daily for the growth of microorganisms for a period of one month. The results showed there was no significant difference in terms of coronal leakage between the three coronal materials used (P=0.478), but the methods of gutta-percha removal did have an impact on the apical leakage (P=0.047). The mean value showed the Peeso-reamer provided less leakage compared to using a hot plugger during the 30-day experimental time period. It was concluded the temporary type of coronal seal of endodontically treated teeth will not prevent coronal leakage if left for a long period of time. In addition, permanent cementation of the post with the coronal restoration should be carried out as soon as possible to prevent recontamination of the root canal.

Evaluation of the apical seal of root canal fillings with different methods

The purpose of the study was to compare dye penetration methods conducted passively, under negative pressure, or under high pressure conditions. Ninety human maxillary incisors were instrumented and obturated with either the lateral condensation or single cone technique. India ink was used as a dye for passive and negative pressure (60 Torr) penetration methods. For dye penetration under high pressure conditions (200 MPa), a colored epoxy resin was used. Apical leakage was linearly measured evaluating both the root surface that showed the highest degree of penetration and all four surfaces of each root. The results revealed no significant difference between passive and negative pressure penetration methods. The amount of apical leakage obtained using dye penetration under high pressure conditions was significantly lower. Lateral condensation and single cone techniques yielded similar sealing abilities. It is concluded that there is no need to use negative pressure for evaluating the sealing ability of root canal fillings in vitro.

Observer variations in radiographic evaluation of endodontic therapy.

Abstract This study was designed to examine observer variations in radiographic interpretations of periapical conditions after endodontic therapy and when assessing the quality of the seal of root canal fillings. Radiographs of 90 teeth with 143 roots and 160 root canals, sampled at random from endodontically treated teeth, were evaluated by 9 dentists (3 endodontist, 3 oral radiologists, 3 general practitioners). Film interpretations were made independently by each observer and they were asked to complete pre‐designed forms where the criteria for the interpretation were noted. Nine weeks later the same radiographs were evaluated by 2 pairs of examiners, each pair consisting of 1 endodontist and 1 general practitioner. Complete agreement among all 9 individual observers was found in 38% of cases for the periapical conditions and in 41% for the quality of the seal. The corresponding figures for the pairs of examiners were 65%, and 57%, respectively.

Fluorometric assay of the apical seal of root canal fillings

Fluorometric assay of the apical seal of root canal fillings