Byline: Mohamed. El Sayed
Aim: The aim of this study was to compare the influence of two irrigation protocols and obturation techniques on the apical seal of three endodontic sealers. Materials and Methods: Crowns of 130 single-rooted teeth were cut and 10 roots were selected as controls, and the remaining roots were divided into four experimental groups (n = 30) according to the type of irrigation protocol and obturation technique. Each group was divided into three subgroups (n = 10) according to the type of root canal sealer. All root canals were prepared with size F4 Protaper Universal and irrigated with 3% sodium hypochlorite (NaOCl) + 3% hydrogen peroxide (H[sub]2O[sub]2) (Groups 1 and 3) or 3% NaOCl + 2% chlorhexidine (CHX) (Groups 2 and 4). Two gutta-percha obturation techniques were used: single-cone (Groups 1 and 2) and continuous wave (Groups 3 and 4) techniques. The following sealers were tested: MTA Fillapex (Subgroup A), AH Plus (Subgroup B), and Realseal SE (Subgroup C). The apical seal was assessed using dye penetration method, and the data were statistically analyzed. Results: In the first group, AH Plus showed the best apical seal (0.46 [+ or -] 0.098 mm), while RealSeal SE system showed the worst apical seal (3.47 [+ or -] 0.434 mm). In the second group, MTA Fillapex (0.58 [+ or -] 0.115 mm) and AH Plus (0.63 [+ or -] 0.109 mm) showed the best apical seal. In the third and fourth groups, all types of sealers showed similar high leakage patterns. Marked increase in the apical seal of RealSeal was observed in the third group (1.71 [+ or -] 0.453 mm). Conclusions: The type of irrigation protocol and obturation technique could affect the apical seal of tested sealers. When the single-cone technique was used, AH Plus with NaOCl + H[sub]2O[sub]2 and MTA Fillapex with NaOCl + CHX irrigation protocols showed significantly a high apical seal. RealSeal SE showed the worst apical seal when canals were irrigated with NaOCl/H[sub]2O[sub]2 and filled with the single-cone technique. All sealers showed inferior results when used with the continuous wave technique.
The aim of a successful root canal treatment is to clean and shape the root canal system to receive a three-dimensional impermeable filling. Gutta-percha is the most common core material, which can be used with different types of root canal sealers and obturation techniques to fill the root canal system.
Warm vertical compaction is a commonly used obturation technique developed by Schilder in 1976. It could improve the adaptation of the obturation materials to the root canal walls and filling of lateral and accessory canals. However, this technique requires a longer time and is difficult to apply. In an attempt to simplify the warm vertical condensation of gutta-percha, Buchanan suggested the continuous wave condensation technique using the System B heating device.
With the widespread use of rotary NiTi instruments, and the introduction of matched-taper gutta-percha or Resilon cones, the noncompaction matched taper single-cone obturation technique has become popular due to its simplicity and...