Anatomic Apex Research Articles

Reliability of Three-Dimensional Micro-Computed Tomography Root Canal Analysis Using Drishti Software: A Pilot Study

In recent years, micro-computed tomography (micro-CT) has become a promising tool for non-destructive imaging and the study of root canal morphology in endodontics. However, the reliability of such analyses heavily relies on the accuracy and consistency of the software used for image processing. Objective: This study aims to investigate the reliability of two different micro-CT voxel sizes using open-source three-dimensional (3D) software (Drishti v3.0) used to identify and quantify the Apical Foramen (AF) and Apical Constriction (AC) in mandibular premolars. Methods: Eight mandibular premolars were divided into two groups, with four samples in each group. Samples were scanned using a ZEISS X-Radia 520 Micro-CT system with two different voxel sizes of 23 µm (Group A) and 17 µm (Group B), respectively. The micro-CT data were reconstructed and transferred to Drishti Software, and individual image rendering was performed to visualize the images for data analysis. The position and measurement of AF and AC to the anatomical apex were measured individually and independently by single operators. Results: The reliability of the measurements assessed using Intraclass Correlation Coefficients (ICCs) between two voxel sizes was excellent and on par with previous research. This pilot study suggested that results for voxel sizes of 23 µm and 17 µm were comparable. Both voxel size 3D images demonstrated excellent and high-quality visualization of the root canal configuration, lateral and accessory canals, apical deltas, major AF, and AC. Conclusion: It is feasible and reliable to visualize and analyze 3D micro-CT images using open-source software (Drishti v3.0). Both voxel sizes of 23 µm and 17 µm are recommended for use in root canal study.

Morphology of the Physiological Foramen: II. Maxillary and Mandibular Premolars

IntroductionInformation concerning the anatomy of the physiological foramen is still limited. The aim of this study was to investigate the distance between the physiological and anatomic apex, the shape and diameter of the physiological foramen in maxillary (Mx) and mandibular premolars (Mn). MethodsThe anatomy of the apex of 229 maxillary (first: MxP1; second: MxP2) and 221 mandibular premolars (first: MnP1; second: MnP2) from a mixed Swiss-German population was investigated by means of microcomputed tomography and 3-dimensional software imaging. ResultsThe following results were obtained in the presence of a main physiological foramen. 1. The distance between the physiological and anatomic foramen was 0.29-0.99 mm (MxP1), 0.21-1.03 mm (MxP2), 0.13-0.8 (MnP1), and 0.15-1.41 (MnP2). 2. The mean narrow and wide diameters of the physiological foramen were 0.19-0.33 mm (MxP1), 0.25-0.42 mm (MxP2), 0.28-0.37 (MnP1), and 0.28-0.40 (MnP2). 3. The most common physiological foramen shape was oval (66.7% MxP1, 89.7% MxP2, 91.8% MnP1, 64.4% MnP2). ConclusionConsidering the recommended preparation sizes based on a size corresponding to the friction, that is at the narrowest point in the area of the apical constriction (physiological foramen), and within the limitations of this ex vivo microcomputed tomography study, a final preparation size could be chosen when considering the pertaining morphologic considerations; yet, to a minimum ISO 30 size.

The Effect of Coronal Pre-flaring and Type of Root Canal Irrigation on Working Length Accuracy Using Electronic Apex Locators.

Background: Successful root canal treatment is influenced by the apical extent of root canal preparation and the eventual root canal filling. Achieving the full working length until the apical constriction, which is usually 0.5 - 1 mm shorter than the anatomical apex, is crucial. Electronic apex locators were used to detect the working length more accurately. There are six generations of electronic apex locators in the market. The selection of the appropriate irrigation with each apex locator for accurate working length determination is not fully investigated. Methods: The actual working lengths of 120 freshly extracted human single-rooted teeth were measured and compared with their working lengths using 3 rd generation (Root ZX) followed by 6 th generation (Raypex 6) apex locators in dry medium, presence of 5.25% sodium hypochlorite, and 2% chlorhexidine, without coronal pre-flaring and after coronal pre-flaring using the same irrigating media. Data were collected, tabulated, and afterward analyzed using one-way ANOVA with post-hoc to evaluate the significant difference in average working length between actual working length, Root ZX, and Raypex 6 apex locator working lengths accuracy. Results: The significant results were shown in roots that were coronally pre-flared and their working lengths were measured in a dry medium using Raypex 6 apex locator. While using the Root ZX apex locator, the most accurate results were shown in roots that were coronally pre-flared and their working lengths were measured while using a chlorhexidine irrigating solution. Conclusions: It is concluded that it is very important to know the specific irrigating medium to be used with each specific electronic apex locator to achieve the most accurate working length results.

Microcomputed tomography (micro-CT) analysis of apical mandibular premolar in relation to clinical sign presentation: An in vitro study

IntroductionVariations in anatomic apex and apical foramina of root canals are common in different teeth types. The sophisticated 3D micro-CT aids researchers in investigating the apical morphology, such as the apical foramen (AF) and constriction (AC). ObjectivesTo measure the length between the foramen and the apex and the physiological length to the apex, in lower premolar teeth. Furthermore, a measurement was conducted on the average length from the foramen to the apex of the lower premolar teeth with respect to the presence of clinical and non-clinical signs. MethodsA total of 80 lower premolar teeth were selected based on the inclusion criteria. All samples were scanned using micro-CT ZEISS X-Radia (17 µm), and the datasets were analysed. The root canal AF and AC were reconstructed using Drishti software (V3.0) by utilising a 4-digit system code in millimetres (mm). ResultsMore than half of the lower premolars (n = 47, 58.8 %) demonstrated a clinical signs presentation, while the rest had a non-clinical sign (n = 33, 41.3 %). There was a significant difference (p = 0.013) between the non-clinical and clinical groups in the mean length from the apical foramen to the apex (AFA) at 0.59 mm and 0.47 mm, respectively. Meanwhile, the non-clinical and clinical mean length from apical constriction to apex (ACA) were 0.75 mm and 0.73 mm, and the mean length from AF to AC (AFC) was 0.48 mm and 0.53 mm, respectively. Nonetheless, no significant differences were detected between the ACA and AFC of non-clinical and clinical groups. ConclusionThe clinical signs presentation observed in lower premolars mainly affected the apical morphology, particularly the position and length of the root AF, and less so the AC position and length. Therefore, the information is useful for clinical purposes.

The difference distance between the apical foramen and the anatomical apex in primary teeth-An in vitro study.

The apex area in the primary teeth changes continuously due to the physiologic resorption, therefore; the apical foramen (AF) may not correspond to the anatomic apex (AA), which gives a big challenge to achieve successful endodontic treatment. The aim of this research was to study the difference distance (DD) between the position of the AA and AF, besides the difference acceptance (DA) in primary teeth, and the effect of the following variables: root canal curvature, resorption degree, and canal size on DD and DA separately. In this research, 180 root canals from 60 primary teeth were studied. Two lengths of each canal were measured by a K-file from a certain point in the crown; the first length was until the AA and the second was until the AF. Then DD was obtained by calculating the difference between those two lengths. Statistical analysis tests were done. A p value of <.05 was considered significant at a 95% confidence level. The percentage of canals with 0 mm DD was 34.4%, while it was 1.1% with DD of 6 mm. The percentages of acceptable ( ≤ 2 mm) and unacceptable ( > 2 mm) difference were 84.4% and 15.6%, respectively. There was a significant difference in the DD value between the three groups of curvature degree and the three groups of canal size. There was a significant difference between the DA in the three groups of canal size. DD has a wide variation value in primary teeth regardless of the degree of root resorption, which has not affected this value or the accepted difference; however, DD and acceptable difference values are somehow affected by the degree of root curvature and canal size. We recommend adding acceptable difference as a criterion when considering pulpectomy treatment in primary teeth.

T-endo must, T-endo mis ve Reciproc Blue Kanal Eğeleri ile Kanal Şekillendirmesi Sırasında Apikalden Taşan Debris Miktarının Karşılaştırılması

OBJECTIVE: The aim of this study was to compare the effect of nickel-titanium file systems with different taper angles working with rotation and reciprocation motion on the amount of debris extruding apically. MATERIALS AND METHOD: The study was performed using the Myers and Montgomery model. Forty-five human maxillary anterior teeth were inserted into preweighed Eppendorf tubes and randomly classified into three groups. After manual glide-path preparation, the teeth in each group were instrumented to the working length set 1 mm short of the anatomical apex using the standard sequence provided by the manufacturers: Group 1: Reciproc Blue (Easy In Smile, New Jersey, USA), Group 2: T-endo must (Dentac, İstanbul, Turkey),Group 3: T-endo mis (Dentac, İstanbul, Turkey). Root canals were irrigated with 10 mL 2.5% NaOCl, 17% EDTA, and distilled water between each file insertion. The tubes with collected debris were stored in an incubator at 70°C for 7 days. Measurement of the weight of extruded debris was performed by subtracting the pre-instrumentation from the post-instrumentation weight of the tubes. Data were analyzed using one-way ANOVA and Tukey’s Honest Significant Difference Test (α=0.05). RESULTS: The weights of the apically extruded debris were 0.0094±0.0015 g in Group 1, 0.0075±0.0012 g in Group 2, and 0.0044±0.0010 g in Group 3, and the difference between all groups was statistically significant (p&amp;lt;0.05). CONCLUSION: The amount of apically extruded debris is related to the taper angle of the file used and the kinematics of the file.

The Effects of Calcium Hydroxide-loaded Poly(Lactic-co-glycolic Acid) Biodegradable Nanoparticles in the ex vivo External Inflammatory Root Resorption Model.

To evaluate the calcium ions (Ca2+) diffusion of calcium hydroxide-loaded poly(lactic-co-glycolic acid) biodegradable nanoparticles [Ca(OH)2-loaded PLGA NPs] compared with conventional Ca(OH)2 in a simulated external root resorption ex vivo model using inductively coupled plasma mass spectrometry (ICP-MS). Thirty human mandibular premolars were prepared by sectioning the root segments to create roots measuring 10 mm from the anatomical apex. The root canals were instrumented and irrigated. The external root surface cavities were created. The specimens were randomly divided into the following three groups: Poly(lactic-co-glycolic acid) (PLGA; control group, n = 10), conventional calcium hydroxide [Ca(OH)2] (Metapaste, n = 10), and Ca(OH)2-loaded PLGA NPs [15% Ca(OH)2, n = 10]. The intracanal materials were placed in the root canals, and the teeth were stored in phosphate-buffered saline at 37°C. The release of Ca2+ was measured at 7, 30, and 60 days using ICP-MS. Both Ca(OH)2-loaded PLGA NPs and Metapaste groups exhibited higher levels of Ca2+ release compared to the PLGA group at all time points. During the initial 7-day period, the Ca(OH)2-loaded PLGA NPs exhibited a significantly greater release of Ca2+ compared to Metapaste. From day 7 to day 30, Metapaste displayed a significantly higher release of Ca2+ than the Ca(OH)2-loaded PLGA NPs, but it experienced a subsequent decline in Ca2+ release after the 30-day period. After the 30-day mark, the Ca(OH)2-loaded PLGA NPs once again exhibited a significantly higher release of Ca2+ compared to Metapaste. The Ca(OH)2-loaded PLGA NPs exhibited sustained release of Ca2+ that exceeded conventional Ca(OH)2, particularly during the first week, demonstrating a greater amount of Ca2+ release. The utilization of Ca(OH)2-loaded PLGA NPs as an intracanal medication for external inflammatory root resorption provided sustained release and had the potential to enhance the efficacy of inhibiting root resorption more effectively than conventional Ca(OH)2.

The effect of coronal pre-flaring and root canal irrigant on apex locators’ accuracy: an in-vitro study

Background: Successful root canal treatment is influenced by the apical extent of root canal preparation and the eventual root canal filling. Achieving the full working length until the apical constriction, which is usually 0.5 – 1 mm shorter than the anatomical apex, is crucial. Electronic apex locators were used to detect the working length more accurately. There are six generations of electronic apex locators in the market. The selection of the appropriate irrigation with each apex locator for accurate working length determination is not fully investigated. Methods: The actual working lengths of 120 freshly extracted human single-rooted teeth were measured and compared with their working lengths using 3rd generation (Root ZX) followed by 6th generation (Raypex 6) apex locators in dry medium, presence of 5.25% sodium hypochlorite, and 2% chlorhexidine, without coronal pre-flaring and after coronal pre-flaring using the same irrigating media. Data were collected, tabulated, and afterward analyzed using one-way ANOVA with post-hoc to evaluate the significant difference in average working length between actual working length, Root ZX, and Raypex 6 apex locator working lengths accuracy. Results: The significant results were shown in roots that were coronally pre-flared and their working lengths were measured in a dry medium using Raypex 6 apex locator. While using the Root ZX apex locator, the most accurate results were shown in roots that were coronally pre-flared and their working lengths were measured while using a chlorhexidine irrigating solution. Conclusions: It is concluded that it is very important to know the specific irrigating medium to be used with each specific electronic apex locator to achieve the most accurate working length results.

Centering ability and root canal transportation of protaper gold and v taper gold using cone-beam computed tomography: An in vitro study

Introduction: This study aimed to evaluate the central ability and root canal transportation of two types of rotary files in curved molar canals using cone-beam computed tomography (CBCT) in mesiodistal (MD) and buccolingual (BL) directions.Method and Material: A total of 40 mesiobuccal root canals of mandibular first molars with an angle of 25-35 degrees and radius curvature of 5 millimeters were randomly divided into two groups of 20 canals each. Group A was prepared with Pro Taper Gold (PTG), and Group B with V Taper Gold (VTG). Pre- and post-instrument CBCT scans were recorded. Images were reconstructed, then cross-sections were detected corresponding to distances of 3, 6, and 9 mm from the anatomic apex using Gambill’s method. Statistical analysis was performed with T-test and repeated measure ANOVA. P-value was set at 0.05.Results: There was a significant difference in centering ratio and canal transportation at all three levels of 3-, 6-, and 9- mm, mesiodistally. PTG has higher centering ability in 6 mm and 9 mm sections with more canal transportation at 3 mm and 6 mm. In the BL direction, no statistically significant difference in central ability was observed among the PTG and VTG groups. The centering ability of both groups became higher from the apex to the coronal part. The last and the most canal transportation in both PTG and VTG groups was reported at 6 mm level and 9 mm level, respectively.Conclusion: Both rotary instruments efficiently cleaned and shaped curved canals. ProTaper Gold had better centering ability, while V Taper Gold showed less canal transportation.

Three-Dimensional Evaluation of the Root Apex of Permanent Maxillary Premolars: A Multicentric Study

Aim: Modern endodontics has advanced radically in the recent years, and recently, it has been focused on the concept of mini-invasive treatments. This study aimed to evaluate the sections of the root apices at 1 mm from the radiographic apex using a high-resolution CBCT. Materials and Methods: The current study was performed in three different dental centers. One hundred maxillary permanent premolars (50 first and 50 s premolars) were analyzed using measurement software of the CBCT radiographic pictures. The mesio-distal (M-D) and bucco–palatal (B-P) sections were measured at 1 mm from the radiographic apex of each root. The section of 0.3 mm or less, 1 mm from the anatomical apex of the upper premolars, was decided as the limit value. All values were statistically analyzed. Results: The mean value in the 304 sections analyzed was 1.03 (±0.37). Only 19 sections (6.3%) had measurements less than or equal to 0.3 mm. All these 19 sections were from first premolars (p = 0.002). Conclusions: Based on the data obtained, the authors recommend performing conservative shaping when endodontically treating first maxillary premolars, especially when a pre-operative CBCT to evaluate the actual apical dimensions cannot be acquired.

Shaping ability of waveone primary reciprocating files and oneshape rotary files in severely curved root canals

Introduction: This study compared the amount of canal transportation, canal centering ability after instrumentation and time required for shaping of canal with WaveOne Primary Reciprocating file and OneShape Rotary file. Method: Thirty intact mesial roots of mandibular first molars were divided into Group I and Group II. Specimens in Group I were shaped with WaveOne Primary reciprocating files to the working length (WL) and specimens in Group II were shaped with OneShape Rotary file to the WL. Time required to prepare each canal was recorded. All the specimens were submitted to micro-computed tomography (µCT) unit for Pre- and post-instrumentation scan. Images were reconstructed and cross-sections corresponding to distances 3, 6 and 9 mm from the anatomic apex were selected for analysis. Statistical analysis was performed with Kruskal Wallis and paired t test. Results: Overall, both rotary files maintained root canal curvatures well. During canal preparation, OneShape file performed significantly better in the apical third when compared to the WaveOne Reciprocating file. WaveOne file required reasonably less time to prepare canal when rather than OneShape file.

In Vitro Qualitative Evaluation of Root-End Preparation Performed by Piezoelectric Instruments.

Although the application of ultrasounds in endodontic surgery allows for effective debridement of the root canal, incorrect device setting or inefficient tips seem to generate cracks during root-end retropreparation. The primary aim of this in vitro study was to establish the presence, or absence, of a correlation between ultrasonic root-end preparation and the formation of cracks. The present study was conducted on human teeth, extracted for periodontal reasons. After root canal treatment, roots were resected 3 mm from the anatomical apex by using a high-speed handpiece and carbide burs. The resected teeth were retroprepared by using an ultrasonic tip (R1D, Piezomed, W&H, Bürmoos, Austria), setting the piezoelectric device at maximum power available for the tip. Time required for the retropreparation was recorded. Before and after retropreparation, all roots were photographed under a stereomicroscope and analyzed by two different operators to evaluate: (a) the presence and extension of dentinal cracks and (b) the morphology of root-end preparation. Finally, piezoelectric tips were analyzed by scanning electron microscopy (SEM) to evaluate morphologic changes after use. A total of 43 single roots (33 with one root canal, 10 with two root canals) were treated. Average preparation time was 1 minute and 54 seconds. None of the roots without initial cracks developed new cracks after retropreparation. Quality of the preparation margins was fairly equal among the prepared specimens. None of the piezoelectric tips broke during instrumentation, and SEM analysis showed minimal surface wear of the tips after performing 11 retropreparations. Within the limits of the present study, the tested piezoelectric system does not seem to represent a major cause for root crack formation. Pre-existing cracks may expand after ultrasound root-end preparation.

Morphological changes of the root apex in anterior teeth with periapical periodontitis: an in-vivo study

IntroductionThe aim was to analyze the morphological changes of root apex in anterior teeth with periapical periodontitis.Methods32 untreated anterior teeth with periapical periodontitis were enrolled, compared with the healthy contralateral teeth. Two-dimensional measurement of Cone-beam computed tomography was used to determine the location and measure diameter of the apical constriction according to Schell’s methods. An open-source software (3D Slicer) was used to reconstruct the teeth. The apical constriction form was analysis according to Schell’s topography. The distances of apical constriction to apical foramen and anatomical apex were measured respectively.ResultsThe difference value between buccolingual and mesiodistal diameter was (0.06 ± 0.09) mm and (0.04 ± 0.04) mm in periapical periodontitis and controls (p < 0.05). The mean distance between apical constriction and anatomical apex was significantly shorter in periapical periodontitis than controls, so was the mean distance of apical constriction to apical foramen. The most common form of apical constriction was flaring (65.6%) in periapical periodontitis.ConclusionsThe anterior teeth with periapical periodontitis had shorter distances of apical constriction to anatomical apex and apical foramen, bigger disparities between the diameters of buccolingual and mesiodistal, and higher proportion of flaring apical constriction.

Morphotypes of the apical constriction of maxillary molars: a micro-computed tomographic evaluation.

ObjectivesThe aim of this study was to evaluate and compare the apical constriction (AC) and apical canal morphology of maxillary first and second molars, using micro-computed tomography (micro-CT).Materials and MethodsThe anatomical features of 313 root canals from 41 maxillary first molars and 57 maxillary second molars of patients with known age and sex were evaluated using micro-CT, with a resolution of 26.7 µm. The factors evaluated were the presence or absence of AC, the morphotypes, bucco-lingual dimension, mesio-distal dimension, and the profile (shape) of AC and the apical root canal. The apical root canal dimensions, location of the apical foramen (AF), AC to AF distance, and presence of accessory canals in the apical 5 mm were also assessed. Descriptive and analytical statistics were used for data evaluation.ResultsAC was present in all 313 root canals. Patients’ age and sex did not significantly impact either AC or the apical canal dimensions. The most common AC morphotype detected was the traditional (single) constriction (52%), followed by the parallel (29%) morphotype. The mean AC dimensions in maxillary first molars were not significantly different from those in maxillary second molars. Sixty percent of AF were located within 0.5 mm from the anatomic apex.ConclusionsThe most common morphotype of AC detected was the traditional constriction. Neither patients’ age nor sex had a significant impact on the dimensions of the AC or the apical root canal. The majority of AF (60%) were located within 0.5 mm from the anatomic apex.

AN In-vitro EVALUATION OF ACCURACY OF THREE ELECTRONIC APEX LOCATORS IN THE PRESENCE OF 3% SODIUM HYPOCHLORITE

The condition known as the variation of the apical foramen and asymmetrical root canal opening is identified when the main foramen of the root canal is not situated at the anatomical apex. Under these conditions, it is possible to determine the working length incorrectly, which might result in many issues that could compromise the effectiveness of the endodontic procedure. In this work, we examined the apical foramen detection accuracies of these three EALs in 3% sodium hypochlorite (NaClO).&#x0D; Materials and Procedures: To clean the teeth and remove organic material stuck to the exterior root surfaces, they were placed in a solution of 3% sodium hypochlorite for six hours. A #15, K-File was used to randomly choose teeth from 1 to 80 for measuring (Mani).&#x0D; Results: Three apex locators failed to detect the apical foramen in the presence of 3% sodium hypochlorite, according to Newman-Keuls multiple posthoc procedures. Dentaport ZX was 90% accurate in finding the apical foramen, Apex NRG was 87.5% accurate, and Propex II was 81.25% accurate within 0.5 mm of the acceptable therapeutic range.&#x0D; Conclusion: EALs may function on an electrical basis rather than the biological characteristics of the tissues involved, according to some research. In vitro models that have periodontium-like electrical resistance may thus provide useful information.

Morphological Assessments of Root Apex of Permanent Mandibular First and Second Premolars in a Turkish Population

There is no apical morphological data being available for mandibular first or second premolars in the Turkish population. The aims of the study were (I) to assess apical morphological data of mandibular first and second premolars in a Turkish population at a young-adult age range (II) to analyze potential correlations between the size and position of the apical foramina (AF). Extracted sound teeth were collected from an adult volunteer population as willing to donate. Morphological data were obtained from specimens using a stereomicroscope. The number, size, shape, and position of AF and frequency of accessory foramina were quantified. Mann-Whitney U and Spearman's rank correlation tests were performed (α=0.05). A total of 237 teeth were investigated. The majority of the specimens had one major AF. The frequency of major AF was between 1–3 for both groups. The median AF size in mandibular first and second premolars were 55,180 µm2 and 67,483 µm2, respectively. The majority of foramina shape was irregular for the mandibular first premolars whereas, was oval for the second premolars. The median location of AF with respect to the anatomic apex was 664 µm in mandibular first premolars and 677 µm in mandibular second premolars. The size and location of AF mostly overlap between the mandibular first and second premolars. The shape of the AF might be the only relevant variation concerning the apical morphology between the mandibular first and second premolars in young adults. The interaction between the size and location of AF in mandibular premolars of young adults seems not significant

Apical Extrusion of Debris during Root Canal Preparation with ProTaper Next, WaveOne Gold and Twisted Files.

(1) Background: Apical extrusion of debris is an example of a complication that may arise during root canal treatment, and it has been proven to be an unavoidable occurrence during endodontic treatment by numerous authors. Even though it may not hinder the long-term outcome of treatment, it may lead directly to increased levels of postoperative pain and, therefore, lower levels of patient acceptance and satisfaction. The aim of the study was to assess the weight of apically extruded debris during root canal preparation with instruments that use different movement kinematics (rotary, reciprocating, and adaptive motion); (2) Methods: The study was performed using the Myers and Montgomery model. Sixty human premolar teeth were inserted into preweighed Eppendorf tubes and randomly classified into three groups. After manual glide-path preparation, teeth in each group were instrumented to working length set 1 mm short of the anatomical apex using the standard sequence provided by the manufacturers (for Group 1: ProTaper Next X1 & X2; for Group 2: WaveOne Gold Primary, for Group 3: Twisted Files SM1-SM3). Root canals were irrigated with 1 mL of 0.9% NaCl solution between each file insertion. The tubes with collected debris were stored in an incubator at 70 °C for 5 days in order to evaporate the liquid component. Measurement of the weight of extruded debris was performed by subtracting the preinstrumentation from the postinstrumentation weight of the tubes. The results were analyzed with Kruskal–Wallis ANOVA, with significance level set at 0.05; (3) Results: The weight of extruded debris was 0.337 mg (SD = 0.148) for Group 1, 0.305 mg (SD = 0.201) for Group 2, and 0.348 mg (SD = 0.135) for Group 3. (4) Conclusions: Engine-driven root canal preparation with the use of instruments ProTaper Next, WaveOne Gold and Twisted Files that use different movement kinematics (rotary, reciprocating, and adaptive motion) was associated with apical extrusion of debris to a similar extent.

Evaluation of apical foramen position and distance from the anatomical apex of roots in anterior maxillary teeth by cone-beam computed tomography (CBCT) in a selected Iranian population

Evaluation of apical foramen position and distance from the anatomical apex of roots in anterior maxillary teeth by cone-beam computed tomography (CBCT) in a selected Iranian population

Micro-computed tomography analysis of root canal morphology and thickness of crown and root of mandibular incisors in Chinese population.

The aim of this study was to investigate the root canal morphology and the thickness of crown and root of mandibular incisors in a Chinese subpopulation by micro-computed tomography (micro-CT). In total, 208 mandibular incisors were scanned using micro-CT. The anatomical features of the canals (canal configuration, apical constriction, foramen-to-apex distance, accessory canal vertical distribution, and canal geometrical parameters) and the thickness of the crown and root 2/3 were evaluated. Three canal categories, labeled as Single (77.88%), Merged (15.87%), and Separated (6.25%), were summarized. The most frequent constriction type in main foramina was single constriction (42.53%). Wide and narrow diameters in a single main foramen were 0.37 ± 0.14mm and 0.26 ± 0.07mm, respectively. The distance from the anatomical foramen to the physiological foramen and the anatomical apex was 0.49 ± 0.20mm and 0.36 ± 0.28mm, respectively. During the virtual root-end resection, 97.12% of roots underwent successful resection at the 2-mm level, with the foramina visible on the resection surface. During 2-D cross-sectional analyses, the shape parameters of the root and canal showed significant positive correlation (P < 0.05). The thickest and thinnest walls were the incisal and proximal walls (P < 0.05) of the crown, respectively. The buccal walls were significantly thicker than the lingual walls on the crown (P < 0.05), whereas the lingual walls were thicker on the root 2/3 (P < 0.05). This study provides detailed information about the root canal morphology and thickness of the crown and root of mandibular incisors in a Chinese population. An understanding of morphology can benefit endodontic treatment. Adequate knowledge of the crown, root, and canal morphology, as well as the thickness distribution of the crown and root, is essential for successful root canal therapy and prevention of complications.

Cone-beam computed tomography analysis of centering ability and root canal transportation of ProTaper gold and v taper blue files in mandibular molar root canal preparation

Introduction: To maintain the original shape of root canals using instruments with minimum effects on canal location is considered an important step in root canal preparation. Canal transportation is a common procedural mistake in the instrumentation of curved canals. This in vitro study aimed to evaluate the central ability and root canal transportation of two types of rotary files in curved canals using cone-beam computed tomography (CBCT). Method and Material: A total of 40 mesiobuccal root canals of human mandibular first molars with an angle of curvature of 25-35 degrees and radius curvature of 5 millimeters were randomly divided into two groups of 20 canals each. Group A was prepared with Pro Taper Gold and Group B with V Taper Blue. Pre- and post-instrument CBCT scans were recorded. Images were reconstructed and cross-sections were detected corresponding to distances 3, 6, and 9 mm from the anatomic apex using Gambill’s method. Statistical analysis was performed with T-test and repeated measure ANOVA. P-value was set at 0.05. Results: No significant difference was observed among Pro Taper Gold and V Taper Blue in terms of centering ability from mesiodistal (P=0.304) and buccolingual (0.632) directions. Also, there was no statistical difference across two different instruments in considering to canal transportation from mesiodistal (P=0.581) and buccolingual (P=0.259) directions. However, in centering ability evaluation, each of the two groups showed significant differences in various levels of coronal, middle, and apical root level (P=0.000). Conclusion: The two instruments were similar in terms of centering ability and canal transportation in mandibular curved canal preparation.