Comparative evaluation of dentin volume removal and centralization of the root canal after shaping with the ProTaper Universal, ProTaper Gold, and One-Curve instruments using micro-CT

Three-Dimensional Printed Teeth in Endodontics: A New Protocol for Microcomputed Tomography Studies

This study aimed to describe a support material removal protocol (SMRP) from inside the root canals of three-dimensional printed teeth (3DPT) obtained by the microcomputed tomography (microCT) of a natural tooth (NT), evaluate its effectiveness by comparing the 3DPT to NT in terms of internal anatomy and behaviour toward endodontic preparation, and evaluate if 3DPT are adequate to assess the differences between two preparation systems. After the SMRP, twenty 3DPT printed by PolyJet™ were microCT scanned before preparation and thereafter randomly assigned into two groups (n = 10). One group and NT were prepared using ProTaper Gold® (PTG), and the other group with Endogal® (ENDG). MicroCT scans were carried out after preparation, and the volume increase, volume of dentin removed, centroids, transportation, and unprepared areas were compared. For the parameters evaluated, no significant differences were found between the 3DPT and NT before and after preparation (p > 0.05), and no significant differences were found between the 3DPT PTG group and the 3DPT ENDG group (p > 0.05). It can be concluded that the SMRP described is effective in removing the support material SUP706B™. PolyJet™ is adequate for printing 3DPT. Furthermore, 3DPT printed with high-temperature RGD525™ have similar behaviour during endodontic preparation with PTG as the NT, and 3DPT can be used to compare two preparation systems.

Comparative Evaluation of Efficiency of Different Endodontic File Systems; Protaper Universal, MTWO, Protaper Next, Trunatomy, I-Race in Terms of Remaining Dentin Thickness: An In vitro CBCT Analysis

Introduction

The longevity of an endodontically treated tooth depends on fracture resistance by preserving more remaining dentin thickness. The aim of this study is to determine which file system preserves more remaining dentin thickness.

Materials and Methods

Protaper universal, M-two, Protaper Next, Trunatomy, I-Race and mandibular first premolar. The removed dentin thickness during instrumentation of each file system was noted by taking the difference of RDT of pre-instrumentation and post-instrumentation with the aid of CBCT.

Results and Discussion

TRN [Group-4] shows the least aggressive cutting with maximal preservation of remaining dentin thickness at 3 mm and 6 mm from the apex at both mesiodistal and buccolingual dimensions. M-two [Group-2] shows maximum removed dentin thickness at 3 mm from the apex both mesiodistal dimension and buccolingual dimension. PTU [Group-1] shows maximum removed dentin thickness at 6 mm from the apex at mesiodistal dimension. M-two [Group-2] shows maximum removed dentin thickness at 6 mm from the apex at the buccolingual dimension.

Conclusion

In this study, it is concluded that the Trunatomy file system preserves more remaining dentin thickness both mesiodistally and buccolingually both 3 mm and 6 mm from the apex.

Apically extruded debris, canal transportation, and shaping ability of nickel-titanium instruments on contracted endodontic cavities in molar teeth

PURPOSE

Apically extruded debris, canal transportation and shaping ability were compared between contracted endodontic cavities (CECs) and traditional endodontic cavities (TECs) after instrumentation with XP-endo Shaper (XPS), ProTaper Gold (PTG), ProTaper for hand-use (HPT) and Hero Shaper.

METHODS

The CECs or TECs groups were sub-divided into 24 groups according to root canal morphology and nickel-titanium (Ni-Ti) instruments. The weight of apically extruded debris was calculated using the Myers and Montgomery model. Pre- and postoperative images of teeth were scanned using micro-CT and the three-dimensional models were constructed and compared.

RESULTS

Under CECs or TECs, XPS and PTG produced less apical debris and formed less canal transportation than HPT and Hero Shaper (P < 0.05). XPS group under CECs extruded less apical debris than that under TCEs for round canals with curvature of 20°-35° (P < 0.05). The centering ratios of four tested instruments were higher under TECs than those under CECs (P < 0.05). The HPT and Hero Shaper had more transportation under CECs than that under TCEs (P < 0.05). No statistical difference was found regarding shaping ability among all the groups.

CONCLUSION

Under CECs, XPS preserves the original root canal anatomy, meanwhile it produces less apical debris than the other instruments.

Undergraduate Endodontic Training and Its Relation to Contemporary Practice: Multicenter Cross-Sectional Study in Saudi Arabia

MATERIALS AND METHODS

An online questionnaire was developed and emailed to all dental schools in Saudi Arabia. This questionnaire was answered by the endodontic undergraduate program director. The data collected were analysed using descriptive statistics.

RESULTS

The response rate was 96.15%, which means twenty-five out of twenty-six dental schools participated in the study. The majority of the academic supervisors was endodontists (92%). The use of magnification and ultrasonic tips was not required by 84% and 76% of the dental schools, respectively. The main endodontic treatment techniques were the step-back technique and gates glidden for cleaning and shaping (76%) and cold lateral compaction for obturation (92%).

CONCLUSIONS

The dental students were supervised by endodontic specialists and trained to use traditional endodontic methods. Encouraging dental educators to train students to use modern technology and equipment would probably improve their graduate clinical skills and performance.

Influence of 17% EDTA and Sapindus mukorossi on the Surface Property of Protaper Gold Rotary Endodontic Instruments

The aim of the study was to evaluate the influence of 17% ethylenediaminetetraacetic acid (EDTA) and ethanolic extract of Sapindus mukorossi (S. mukorossi) in combination with canal shaping on surface properties of ProTaper Gold rotary endodontic file. Sixteen F1 ProTaper Gold rotary files underwent the standard protocol for root canal treatment using two irrigants (S. mukorossi and 17% EDTA) in single-rooted decoronated teeth. Eight unused files were used as a control. All files were examined under an atomic force microscope (AFM) to evaluate surface roughness (Ra) and root mean square (RMS). Data were analyzed using the t-test. RMS and Ra values of the control file were 1.37 and 0.607, respectively. The mean RMS (3.70 ± 1.41) and mean Ra (2.89 ± 1.41) in EDTA group were significantly higher than the control file (p < 0.05). The mean RMS in the S. mukorossi group (1.77 ± 0.66) did not show any significant difference with the control (p > 0.05). The Ra of S. mukorossi group (1.09 ± 0.05) was significantly higher than the control file (p < 0.05). Moreover, the mean RMS and Ra were found to be significantly higher in the EDTA group compared to the S. mukorossi group (p < 0.05). The mean Ra and RMS values of the ProTaper Gold files used to prepare canals using 17% EDTA and S. mukorossi irrigation were significantly higher than the control files. The EDTA-treated ProTaper Gold rotary files demonstrated higher surface Ra and RMS than the S. mukorossi files.

Shaping ability of modern Nickel-Titanium rotary systems on the preparation of printed mandibular molars

Introduction

This study aimed to evaluate the shaping ability of TruNatomy (Dentsply Maillefer, Ballaigues, Switzerland), VDW.ROTATE (VDW GmbH, Munich, Germany) and ProTaper Gold (Dentsply Maillefer, Ballaigues, Switzerland) during the preparation of resin-printed mandibular molar mesial root canals.

Materials and Methods

Thirty-three printed resin-based mandibular mesial roots with two canals were obtained from extract tooth cone-beam computed tomography (CBCT) image. The printed teeth were divided into three groups (n = 11) according to the system used for root canal preparation: TruNatomy, VDW.ROTATE, and ProTaper Gold. The specimens were scanned using CBCT imaging before and after root canal preparation. Then images were registered using a dedicated software and changes in the canal area, volume, untouched canal surface, and the maximum and minimum dentin wall wear were calculated.

Statistical Analysis Used

Data were statistically analyzed using Shapiro-Wilk for normality, one-way ANOVA, and Tukey or Kruskal-Wallis H tests with alpha set at 5%.

Results

No differences were observed for changes in the canal area, volume, untouched canal surface area, and minimum dentine wall wear parameters for the whole canal length (P > 0.05). The mean of untouched canal surface area for the TruNatomy, VDW.ROTATE, and ProTaper Gold was 40%, 44%, and 44%, respectively. The maximum dentine wall wear was significantly lower in the ProTaper Gold group than in the TruNatomy and VDW.ROTATE groups (P < 0.05).

Conclusions

TruNatomy, VDW.ROTATE, and ProTaper Gold systems showed similar shaping ability in printed resin-based mandibular mesial roots without clinically significant errors. A large amount of untouched canal surface area was observed for all systems.

Canal Transportation and Volumetric Dentin Removal Abilities of Ni-Ti Rotary File Systems in Curved Primary Root Canals: CBCT Study

Current improvements in nickel-titanium (Ni-Ti) rotary file systems have created a paradigm shift in the root canal therapy of primary teeth. Therefore, it is necessary to perform a comprehensive evaluation regarding the efficiencies of newly manufactured instruments for different parameters. The current study was conducted to evaluate the abilities of RaceEvo, R-Motion, ProTaper Gold (PTG) systems in curved primary root canals with regard to the patterns of canal transportation and volumetric dentin removal by using cone-beam computed tomography (CBCT). Two experimental sets were designed following the determination of experimental groups by using pre- and post-operative CBCT data: canal transportation and volumetric dentin removal. The highest amount of canal transportation was significantly detected in the PTG group in comparison to RaceEvo and R-Motion groups. When the mean values of volumetric dentin removal data were analyzed across all groups, the PTG group again exhibited the significantly highest value of dentin removal volumetrically, compared to RaceEvo, R-Motion and manual instrumentation groups. It is possible to state that R-Motion and RaceEvo rotary systems could be used as reliable alternatives without causing adverse mechanical effects and maintaining the original root canal anatomy of curved primary root canal systems compared with PTG rotary systems and manual instrumentation, with a high diagnostic sensitivity of CBCT in pediatric endodontics when the alternative methods are not adequate.