Journal of Conservative Dentistry最新文献

Background: Determination of working length (WL) is necessary for the successful outcome of root canal treatment (RCT). Common methods in WL determination include tactile, radiographic, and electronic apex locators (EAL).

Aim: The aim of this study was to compare three methods of WL determination to the actual visualization of the apical constriction (AC).

Materials and methods: Consecutive patients with indications for extraction of single-rooted single canal teeth at the University of Ghana Dental School clinic were randomly assigned to three groups. In-vivo root canal WL was determined by tactile sensation, digital radiography, and a 5^th generation EAL (Sendoline S5). Files were cemented in the canals after the in-vivo measurements. The apical 4-5 mm of the roots was trimmed to expose the inserted files and the AC. Actual WL, as determined by visualization of the AC, was done using a digital microscope. Different WLs were then compared for the various groups, and the mean actual canal lengths were reported.

Results: EAL accurately predicted the AC in 31 (96.9%) teeth, while the digital radiographic and tactile sensation methods accurately predicted the constriction in 19 (59.4%) and 8 (25%) teeth, respectively, in the study population. The mean working canal lengths for single-rooted teeth showed no observable difference among sexes, age categories, and side of the jaw.

Conclusion: The EAL provided more reliable and accurate WL measurements for single-rooted teeth among Ghanaians, compared to digital radiography and tactile methods.

Context background: Guided endodontics has various applications, one of which is for calcified canal negotiation. Recently, a new single-tooth template has been fabricated to overcome the drawbacks of bulky guides, which are difficult to use with rubber dam isolation.

Aim: This study aimed to assess the efficacy of the novel single-tooth template for negotiation of pulp canal calcification (PCC) in three-dimensional (3D)-printed resin incisors by comparing substance loss and time taken between incisal endodontic access (IEA) and single-tooth template-guided endodontic access (SGEA).

Methods: Forty-two resin incisor teeth having patent canal in the apical third were used (N = 21/group). They were subcategorized based on operator's experience into senior endodontist (SE), postgraduate (PG), and undergraduate (UG) (n = 7/operator). Canals were negotiated conventionally for IEA and using the single-tooth template for SGEA. Substance loss was calculated from the volume difference between pre- and postoperative cone-beam computed tomography scans. The time taken was also recorded.

Statistical analysis used: Statistical analysis was performed using unpaired t-test and one-way analysis of variance test.

Results: Canals were successfully negotiated in 100% and 95% of teeth in the SGEA and IEA groups, respectively. Overall substance loss and time taken were significantly lesser for SGEA for all operators (P < 0.001). In the IEA group, post hoc test showed statistical significance between SE and UG for substance loss (P < 0.05) and SE-UG and PG-UG for time taken (P < 0.05). No significant difference among operators was noted for both parameters in SGEA.

Conclusions: SGEA resulted in significantly lesser substance loss and time taken for canal negotiation in 3D-printed resin incisors with simulated PCC. This was independent of the experience levels of the operator.

Aim: The aim of this study was to assess and compare the quantity of apically debris which was extruded apically by TruNatomy (TN), ProTaper Next (PTN), HyFlex electric discharge machining (EDM), and HyFlex controlled memory (CM), following root canal preparation.

Materials and methods: Sixty extracted single-canal mandibular premolars were used. The root canal preparation was done with TN, HyFlex EDM, PTN, or HyFlex CM files. The preweight debris, which was extruded apically, was collected in the Eppendorf tube and later on incubated at 670°C for 3 days and weighed again to record the extruded debris.

Results: The result showed that there was a significant reduction in debris extrusion by TN system, followed by PTN system, HyFlex EDM, and maximum extrusion in HyFlex CM (P < 0.05). Between the PTN and TN groups as well as between the HyFlex EDM and HyFlex CM groups, statistically significant difference was not observed (P > 0.05).

Conclusion: Apical debris extrusion is the inherent nature of the all file systems. Nevertheless, the TN file system produced substantially minimum debris extrusion among other systems compared in the study.

One of dentistry's primary objectives is the long-term maintenance of teeth. Hemisection may be the best line of action when only one root is decayed and the other one is intact. This case report outlines and depicts a situation in which the deteriorated terminal abutment was part of a cantilevered fixed prosthesis. Hemisection and prosthesis rehabilitation had successful outcomes.

Background: Perforation repair materials should have excellent sealing ability and dislodgement resistance. While several materials have been employed for perforation repair, newer calcium-silicate materials, such as Biodentine and TheraCal LC, have shown promising outcomes.

Aims: This study aimed to evaluate the effect of different irrigants on the dislodgement resistance of Biodentine and TheraCal LC when used for perforation repair in simulated conditions.

Methods and material: 3% sodium hypochlorite, 2% chlorhexidine gluconate, and 17% EDTA were evaluated for their effect on the dislodgement resistance of Biodentine and TheraCal LC. 48 permanent mandibular molars were selected for the study. The samples were divided into two groups: Group I - Biodentine and Group II - TheraCal LC, with 24 samples each.

Statistical analysis: The mean dislodgement resistance and standard deviation of Group I (Biodentine) and Group II (TheraCal LC) were compared and Failure pattern analysis was done.

Results: Biodentine showed a significant decrease in push-out bond strength after contact with 3% NaOCl, 2% CHX, and 17% EDTA whereas, TheraCal LC showed no significant decrease in push-out bond strength after exposure to 3% NaOCl, 2% CHX, and 17% EDTA.

Conclusions: Overall, TheraCal LC can be considered good perforation repair material with excellent physical and biological properties.

Introduction: The objective of this in vitro study was to examine the impact of different endodontic chelating agents on the flexural strength and microhardness of root dentin.

Materials and methods: Fourty dentin sticks of (1 mm × 1 mm × 12 mm) were obtained from 10 single-rooted premolars and divided into four groups (n = 10). One stick from each tooth was assigned to one of the experimental groups and was soaked in one of the experimental chelating solutions for 5 min 17% ethylenediaminetetraacetic acid (EDTA), 2.5% phytic acid (PA), 18% etidronic acid, or saline (control group). Following the 5-min soak, the sticks' flexural strength was evaluated using a 3-point loading test using the universal testing machine, and the surface microhardness was tested using a Vickers's microhardness tester.

Results: PA (2.5%) and etidronic acid (18%) showed no significant detrimental effect on either the flexural strength or the surface microhardness of radicular dentin compared to the control. EDTA (17%) exhibited a significant drop in the flexural strength and microhardness of radicular dentin compared to the other groups.

Conclusions: PA and etidronic acid chelators do not compromise the surface and bulk mechanical properties of radicular dentin.

Aim: The aim of the study was to evaluate the canal transportation and centering ability of rotary and reciprocating file systems using cone-beam computed tomography.

Materials and methods: Mesiobuccal canals of sixty mandibular molars were selected for the study. Canals of length 19 mm, curvature of 10°-12°, and uncalcified with fully formed apex were selected. Canals were randomly divided into three groups of 20 teeth, and canal preparation with the WaveOne Gold, TruNatomy, and One Curve systems was performed according to the manufacturers' instructions. Cone-beam computed tomographic images were taken before and after instrumentation in the same position for comparative analysis.

Statistical analysis used: Apical transportation was calculated at the distances of 2, 3, and 4 mm from the apex. Tukey's post hoc test and unpaired "t"-tests were used to statistically analyze the data.

Results: WaveOne Gold caused less canal transportation and better-centering ability than TruNatomy and One Curve at all the three levels; there was a significant difference in canal transportation and centering ability among all the groups as well as all the three levels, i.e., 2, 3, and 4 mm from the apex.

Conclusion: WaveOne Gold (Reciprocating) reported less canal transportation and better-centering ability than rotary instruments TruNatomy and One Curve (Rotary) at all the three levels.

Context: The purpose of this study was to evaluate and compare the centering ability and canal transportation of TruNatomy, OneCurve, and Jizai file systems to assess their performance in oval-shaped canals using cone-beam computed tomography imaging.

Materials and methods: Forty-two fully formed single-rooted mandibular premolars were selected with a buccolingual canal size 2-2.5 times the mesiodistal size at 5 mm from the apex, with 0°-10° canal curvature with a 5-6 mm radius, at 5 mm from the apex. The teeth were divided into three groups (n = 14) and prepared with TruNatomy, OneCurve, and Jizai files based on the manufacturer's instructions. Cone-beam computed tomographic images were taken before and after instrumentation. The canal transportation and centering ability was calculated at 3, 6, and 9 mm from the apex in both mesiodistal and buccolingual directions.

Statistical analysis: Intergroup comparison was done using Kolmogorov-Smirnov test. Intragroup comparison was done using Freidman test. A comparison of categorical variables was done using the Chi-square test.

Results: The results obtained did not present any statistically significant difference between the three groups, with TruNatomy and OneCurve showing relatively lesser canal transportation and better centering ratio when compared to the Jizai file system.

Conclusions: It can, therefore, be concluded that all three systems used in the study are capable of safely preparing root canals with minimal errors.

Aims: The aim of the study is to compare the dissolution effectiveness of xylene, thyme oil, and orange oil on three different endodontic sealers.

Materials and methods: Standardized stainless steel molds were used to prepare 210 samples (70 for each endodontic sealer). The samples were divided into three groups based on sealers. Three experimental groups with 20 samples each were immersed in organic solvents. One control group of 10 samples was immersed in distilled water. Each group was further subdivided into two subgroups based on immersion time (2 and 10 min). Inferential statistics included one-way ANOVA, post hoc Tukey, and paired t-test.

Results: Thyme showed significantly more dissolution capacity at 10 min compared to 2 min in dissolving AH Plus sealer whereas this difference was nonsignificant for Roekoseal and MTA Fillapex. Orange oil showed significantly more dissolution at 10 min compared to 2 min in dissolving AH Plus sealer and Roekoseal whereas this difference was nonsignificant concerning MTA Fillapex. Xylene showed significantly more dissolution capacity at 10 min compared to 2 min in dissolving AH Plus sealer, Roekoseal, and MTA Fillapex.

Conclusions: Among the three solvents, xylene showed the highest dissolution of all three sealers. Orange oil was superior to thyme oil in dissolving the sealers. All the sealers showed more dissolution in all the solvents at 10 min compared to 2 min.