root canal obturation

Obtaining a correct working length is critical to the success of endodontic therapy. The aim of this clinical study was to compare the effect of working length determination using electronic apex locator or working length radiograph on the length adequacy of final working length as well as the final obturation.A total of 84 patients with 188 canals were randomized into two groups; in group 1, the working length was determined by working length radiograph, whereas in group 2, it was determined by the Raypex5 electronic apex locator (VDW, Munich, Germany). Length adequacy was assessed in each group for master cone and final obturation radiography and categorized into short, acceptable, and over cases.There was no statistically significant difference between the rates of acceptable (master cone radiography: group 1 = 82.1% and group 2 = 90.4%; final radiography: group 1 = 85.7% and group 2 = 90.4%) and short cases (master cone radiography: group 1 = 7.1% and group 2 = 8.7%; final radiography: group 1 = 1.2% and group 2 = 1%) between the two groups. Over cases in master cone radiography were significantly more in group 1 (10.7%) than group 2 (1%) (χ2, p = 0.00). However, this category did not show a significant difference for final obturation between group 1 (13.1%) and group 2 (8.7%).The results of endodontic treatment using the Raypex5 electronic apex locator are quite comparable, if not superior, to radiographic length measurement regarding the rates of acceptable and short cases. Furthermore, in addition to reducing the radiographic exposure, electronic apex locators are superior in reducing overestimation of the root canal length.

Aim To investigate the attitudes of general dental practitioners (GDPs) and endodontists in the UK towards management of fractured endodontic instruments.Methodology A questionnaire was sent to 330 systemically selected GDPs and all endodontists working in the UK (170). It was accompanied by a covering letter explaining the aims of the study and indicating that all the information given would remain confidential. Those who did not respond to the first mailing were sent another two mailings. Data were analysed using chi-square test at P ≤ 0.05.Results The overall response rate was 75%. Only 18.5% of respondents reported that they would retrieve instruments located in the apical third of root canals with a significantly higher proportion of endodontists (25.9%) compared with that of GDPs (14%) doing so. A significantly higher proportion of endodontists (98.5%) used ultrasonics for removal of fractured instruments compared with GDPs (75.8%). The most common complication of fractured instrument retrieval was thought to be excessive removal of dentine (67%). The majority of respondents (88.5%) reported that they would leave the unsuccessfully removed file in situ and obturate the root canal.Conclusion Both endodontists and GDPs were aware of the limitations of root canal anatomy when removal of fractured instruments was considered. Excessive removal of dentine, the most common complication associated with the removal process, suggests the need for more conservative techniques. Both endodontists and GDPs demonstrated a conservative approach when management of fractured instruments failed. Further studies regarding attitudes of GDPs and endodontists towards some specific aspects of fractured instruments management are required.

The objective of this study was to compare the quality of Guttaflow (Coltene/Whaledent, Langenau, Germany), Resilon/Epiphany (Jeneric/Pentron, Kusterdingen, Germany), and EndoREZ (Ultradent Products, Inc, South Jordan, UT) root canal fillings. Thirty single-rooted teeth were randomly assigned to three groups: Resilon/Epiphany, EndoREZ, and Guttaflow. After radiography of the root canal fillings, the roots were sectioned horizontally at the level of 2 mm and 4 mm from the apex. The area of voids and adaptation to canal walls and points were evaluated using light microscopy and calculated through a computer program. The radiographs showed no significant differences between the materials (p > 0.05, Mann-Whitney U test). Evaluation of cross-sections revealed sealer adaptation >99% to the root canals and >98% to the points. Resilon/Epiphany had significantly higher values at 98.8% (standard deviation [SD] = 3.9%) than EndoREZ at 98.7% (SD = 1.1%), and Guttaflow at 98.5 (SD = 2.1...

Cleaning the root canal is not possible without using proper irrigation. The aim of this in vitro study was to evaluate the effect of MTAD as a final irrigant on bacterial leakage of the root canal, and its interaction with two conventional root canal sealers. We used 132 extracted human maxillary anterior teeth. The teeth were randomly divided into three experimental groups (n=40) and two groups (n=6) of positive and negative control. In group 1, the smear layer was not removed and irrigation was performed using 5.25% NaOCl. In group 2, the smear layer was removed using EDTA, and in group 3, the smear layer was removed using MTAD according to the clinical protocol of use. The teeth in each group were obturated with gutta-percha and AH-Plus or Rickert sealer. The coronal portion of each root was placed in contact with inoculum of Streptococcus mutans in Brain Heart Infusion (BHI) culture media. Each root tip was placed in one bottle containing sterile BHI. Mean duration of bacterial...

Previous studies have indicated that vertical root fracture tends to occur in a buccolingual direction, where dentin thickness is greatest. Factors potentially influencing the location and direction of root fracture include root canal shape, external root morphology, and dentin thickness. In this finite-element study, simulated root sections were varied systematically with respect to canal size and shape, external root morphology, and dentin thickness to determine their relative contribution to vertical root fracture. Similar models were constructed based on cross-sections of human tooth roots that had been fractured clinically or experimentally. Finite-element models demonstrated that canal curvature seems more important than external root morphology, in terms of stress concentration, and that reduced dentin thickness increases the magnitude but not the direction of maximum tensile stress. Models based on actual root fractures showed a strong similarity between tensile-stress distr...

The aim of this study was to compare the in vitro sealing ability of ProRoot MTA, ProRoot MTA (Tooth-Coloured Formula), ordinary Portland cement and white Portland cement when used as root-end filling materials. Twenty-four single-rooted human premolars were prepared and obturated using standard techniques, then retrofilled with the test materials. The prepared teeth were immersed in 1% methylene blue dye for 72 hours and then assessed for dye leakage. The depth of dye penetration was measured and expressed as a percentage of the length of the retrofilling. Data was analysed using ANOVA and Fisher's Least Significant Test (LSD) (p < 0.05). None of the teeth in any of the test groups showed leakage beyond the retrofillings. Given the low cost and apparently similar sealing ability of the cements, it is reasonable to consider Portland cement as a possible substitute for MTA as a root-end filling material. However, further tests, especially in vivo biocompatibility tests, need to be conducted before Portland cement can be recommended for clinical use.

Root fractures are rare occurrences through all dental injuries. They comprise only 0.5% to 7.0% of traumas affecting the permanent teeth. Generally the cervical and middle thirds of the roots are affected. The healing of these lesions depends on the health of the pulp, dentine, cementum, and alveolar bone. These case reports describe the management and 2-year follow-up of 3 maxillary central incisors with horizontal root fractures treated with mineral trioxide aggregate (MTA) as apical plug.

The aim of this study was to evaluate in vitro the apical sealing ability of cold lateral and system B root filling techniques using dye penetration. Eighty-six extracted single-rooted human teeth were prepared and randomly divided into two experimental groups to be obturated by cold lateral condensation (n = 33) and system B (n = 33). The remaining 20 teeth served as positive and negative controls. The roots were embedded for 72 h in methylene blue dye solution and sectioned transversely for dye penetration evaluation using stereomicroscope. The results of this study showed that cold lateral condensation leaked significantly more (P < 0.001) than system B technique.

Purpose: The aim of this study was to evaluate the effect of endodontic and restorative treatment on the fracture resistance of posterior teeth.Materials and Methods: Fifty intact premolars were selected and randomly placed into five groups (n = 10): G1, intact teeth (control); G2, mesial-occlusal-distal (MOD) preparation; G3, MOD preparation restored with composite resin (Z-250, 3M ESPE); G4, MOD preparation and endodontic treatment; and G5, MOD preparation, endodontic treatment, and composite resin restoration. The specimens were submitted to an axial compression load in a mechanical test machine (EMIC), at a speed of 0.5 mm/min. Fracture patterns were analyzed at four levels. Five 2D numerical models were created by Ansys 10.0 for finite element analysis (FEA).Results: Mean values of compressive strength for all groups were (Kgf): G1 (83.6 ± 25.4); G2 (52.7 ± 20.2); G3 (82.1 ± 24.9); G4 (40.2 ± 14.2); G5 (64.5 ± 18.1). Statistical analysis (ANOVA and Tukey's test) showed that fracture resistance of G1 was significantly higher than that of G5, G2, and G4. Resistance of G3 was also higher than that of G2 and G4. Results showed that the tooth resistance is completely maintained when MOD preparation is restored with composite resin and partially recovered when MOD preparation associated with an endodontic access is restored in the same way. The endodontic treatment and composite resin restoration influenced stress distribution in the dental structure.Conclusions: Composite resin restoration plays an important role in recovering tooth strength. With regard to fracture mode, restoration and endodontic treatment increased the incidence of periodontal involvement, which was demonstrated by association with the finite element mechanical test method.