In vitro comparison of gutta-percha-filled area percentages in root canals instrumented and obturated with different techniques

Comparative evaluation of the quality and homogeneity of different obturating systems using cone-beam computed tomography - An in vitro study

Aim

The aim of this study was to evaluate the homogeneity and quality of different obturating systems using cone-beam computed tomography (CBCT).

Materials and Methods

One hundred and twenty extracted maxillary and mandibular molars were included in this study which was decoronated first and then dissected into palatal and distal roots. After working length determination, all the roots were biomechanically prepared with ProTaper universal system. The prepared roots were evaluated using CBCT, and volumetric analysis was done. Samples were then randomly divided into three groups corresponding to the obturation method used - cold lateral compaction technique, single-cone technique, and BeeFill 2 in 1 system. After obturation, CBCT imaging and volumetric analyses were performed again to compare and analyze the amount of volume of obturation in different obturating techniques. To standardize the volume, pre-and postobturation images were superimposed. To avoid errors, for each section, measurements were repeated three times and the means were calculated.

Statistical Analysis Used

The data were statistically analyzed using one-way analysis of variance, followed by post hoc test.

Results

Results showed a statistically significant difference of the single cone with lateral compaction and the BeeFill system (P < 0.001). Maximum volume of obturating material was found in BeeFill at all levels - Coronal, middle, and apical, followed by cold lateral compaction and single-cone technique (P < 0.001).

Conclusion

It could be concluded that the thermoplasticized obturating technique can be a better choice for obturation rather than the single cone and lateral compaction technique.

Adaptation of a Single-Cone in Prepared Teeth with Two Reciprocating Systems

Introduction

This ex vivo study aimed to compare the adaptation of single gutta-percha cone in teeth prepared with the Wave One Gold and Reciproc Blue reciprocating systems through cone-beam computed tomography.

Materials and Methods

A total of 40 recently extracted mono radicular premolars were randomly assigned into two groups (n=20) corresponding to Reciproc Blue and Wave One Gold reciprocating systems and adapted to a single cone system. Each group was evaluated by cone-beam computed tomography at 1 mm, 2 mm and 4 mm from the apical foramen. We evaluated the number of walls adapted by the cone, quality of filling and the number of spaces between the filling and the walls of the root canal. The Mann-Whitney U and T-tests were employed to associate and compare both groups (P<0.05).

Results

At 1 mm in the lingual wall the Wave One Gold system did not adapt by 45% compared to 15% with Reciproc Blue (P<0.05). Likewise, the single-cone filling technique of the Reciproc Blue system showed better sealing quality obtaining an ideal category (75%) compared to Wave One Gold (40%) (P<0.05). The amount of space (mm) found between the cone and the filling walls was greater with Wave One Gold. However, these values were not statistically significant.

Conclusions

Based on this ex vivo study the better adaptation of root canals and ideal filling condition was more frequent with Reciproc Blue than Wave One Gold system, mainly at 1 mm from the radicular apex.

Thermafil: A New Clinical Approach Due to New Dimensional Evaluations

Background

There are a lot of techniques to obturate the root canals, but lateral condensation of gutta-percha is the most used one. An important aspect of thermafil is the error margin tolerated by the manufacturer in the production of plastic carriers. In literature, there is no evidence about discrepancy percentage between different carriers. It is demonstrated that the error margin of gutta-percha is 0.5% and is 0.2% for metal files (ISO standards).

Objective

The aim of this study was to evaluate the real dimensions of thermafil plastic carriers observed by the stereo microscope measuring the dimensional discrepancy between them.

Methods

For this study, 80 new thermafil (Dentsply Maillefer) have been selected. 40 thermafil 0.25 and 40 thermafil 0.30. Through 60X stereo microscope, the dimensions of the plastic carrier tips have been measured. The dimensions of the plastic carrier were also measured after a heating cycle. ZL GAL 11TUSM (Zetaline stereo evolution) microscope was used to observe the samples. Measurements were made through a dedicated software (Image Focus). All samples were analysed at 60X.

Results

A non-parametric paired test (Wilcoxon test) was used to compare baseline and after heating values; p-values ≤ 0.05 were assumed to be statistically significant.

Conclusion

The samples we measured showed a mean value of the diameters in Thermafil 25 that was 0.27 mm, for Thermafil 30 the mean value was 0.33 mm.We have measured a dimensional variable of 8% in the 25 group while in group 30 the maximum possible variation found was 4%, that's why we propose a new protocol of obturation with thermafil. We can also conclude that a single heating process does not affect clinically the plastic carrier dimensions.