Effects of cone-beam computed tomography with different FOV parameters on simulated internal root resorption volume

Objective: Various radiographic methods are used to identify the internal root resorption. The aim of this study was to assess and compare the diagnostic accuracy of cone-beam computed tomography (CBCT), photostimulable phosphor (PSP) imaging plate, charge coupled device (CCD), and conventional intraoral radiography (CIR), for internal root resorption.Methods: This experimental study was conducted in Hamadan in 2012. Fifty seven carries-free anterior teeth were divided into three intervention groups of 15 teeth and one control group of 12 teeth. Teeth were split into two parts using a disk. Cavities of 0.5, 1 and 1.5 mm in depth were created in root canal of teeth to simulate internal root resorption artificially. Finally, the teeth fragments were fused. All teeth were examined with four different procedures and the results were compared with known simulated internal root resorption as the gold standard to determine the sensitivity and specificity of the procedures.Results: The sensitivity of CBCT, PSP, CCD, and CIR for diagnosis internal root resorption of 0.5 mm in depth was 93%, 73%, 60%, and 53% respectively. The sensitivity of all four procedures for diagnosis of internal root resorption with 1 and 1.5 mm in depth was the same and equal to 100%. Specificity of the four radiology procedures for diagnosis of internal root resorption of any depth was 100%, 100%, 83% and 75% respectively.Conclusion: CBCT provides the most accurate information on the depth and location of root resorption followed by the PSP and CCD respectively. Accordingly, conventional intraoral radiography was the least accurate procedure.

To examine the influence of the field of view (FOV) and voxel size on the measurement of the volume of simulated internal root resorption (IRR) lesions through cone-beam computed tomography (CBCT). Eleven single-rooted teeth with IRR simulated by acid demineralization were studied. CBCT images were acquired using large FOV (voxel sizes of 0.200, 0.250 and 0.300 mm) and limited FOV (voxel sizes of 0.076, 0.100 and 0.200 mm). The IRR volumes were calculated using the Dolphin(®) software. Volumetric measurements were validated using IRR silicone putty casts. The analysis of variance (anova) for randomized block design complemented with the Tukey's test was employed. IRR volumes obtained using voxel sizes of 0.200 and 0.250 mm were similar (P > 0.05). However, both these values were significantly different from that obtained using the 0.300-mm voxel (P < 0.05). There was no significant difference between IRR volumes measured through voxel sizes of 0.076 and 0.100 mm (P > 0.05), but both differed significantly from that obtained through the 0.200-mm voxel (P < 0.05). There was no significant difference between the volumetric measurements of the 0.200-mm voxel images of the restricted and large FOV protocols. The mean volumes of the silicone casts were smaller than those calculated using a 0.200-mm voxel, but were similar to those obtained using voxel sizes of 0.076 and 0.300 mm. Despite the FOV protocol, voxel size can influence measurement of simulated IRR volumes. The importance of standardization of CBCT image acquisition protocols is emphasized, especially during follow-up of an IRR lesion, to prevent misinterpretation of its extent, which can create a bias in clinical decisions.

BackgroundTeeth with internal root resorption (IRR) have guarded prognosis, considering that IRR defect could influence on the post bond strength. The aim of this study was to evaluate the bond strength and the bond interface between different glass fiber-reinforced posts (FRP) after cementation in teeth with simulated internal root resorption (IRR). Material and MethodsForty-five (45) human premolar roots with simulated IRR were embedded in acrylic resin blocks and cross-sectioned into two segments, enabling them to be re-approximated by screws. Intracanal medication was inserted for 15-days, removed by passive ultrasonic irrigation (PUI) and examined by stereomicroscopy. The push-out bond strength of two fiber reinforced composite posts (Rebilda Post - RP) and Rebilda Post GT – GT, (VOCO) were evaluated at the cervical and IRR regions (n = 20). And, the bonded interface between resin cement and root dentine was analysed by scanning electron microscopy (SEM). Results62.5% of IRR were not completely cleaned by PUI. Bond strength values at the cervical region (9.8 and 14.6 MPa) were higher than the IRR region (6.3 and 4.2 MPa). Micrographies showed bubbles in the cement and spaces in the bonded interface. ConclusionsRP post showed better bond strength at the cervical region while GT had better bond strength at the IRR region. Key words:Endodontics, root canal filling materials, root resorption, X-Ray microtomography.

Observer Ability to Detect Ex Vivo Simulated Internal or External Cervical Root Resorption

This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) - Bio-C Temp and Ultracal - after different activation protocols in teeth with simulated internal root resorption. Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P &gt; 0.05). There was no difference between activation protocols (P &gt; 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P &lt; 0.05), except for Easy Clean (P &gt; 0.05). Due to this, it can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption.&#x0D;

ObjectivesThe obturation quality of MTA, Biodentine, Total Fill BC root canal sealer (RCS), and warm gutta-percha (WGP) in teeth with simulated internal root resorption (IRR) was evaluated by using micro-computed tomography.Materials and MethodsStandardized IRR cavities were created using 40 extracted maxillary central incisor teeth and randomly assigned into 4 groups (n = 10). IRR cavities were filled with MTA, Biodentine, Total Fill BC RCS (bulk-fill form) and WGP + Total Fill BC RCS. Percentage of voids between resorptive cavity walls and obturation material (external void), and inside the filling materials (internal voids) were measured.ResultsTotal Fill BC sealer in the bulk-fill form presented significantly highest values of external and internal void percentages (p < 0.05). Biodentine showed a significantly lowest external void percentage (p < 0.05). WGP + Total Fill BC RCS presented significantly lower values of internal void percentages than all groups (p < 0.05), except Biodentine (p > 0.05).ConclusionNone of the filling materials were created void-free obturation in resorption cavities. Biodentine may favor its application in teeth with IRR over Angelus MTA and bulk-fill form of Total Fill BC.

The aim of this study is to evaluate the effect of different irrigation activation methods on root canal sealer penetration in teeth with simulated internal root resorption (IRR) and calcium hydroxide (CH) applied using a confocal laser scanning microscope (CLSM). 60 incisors with a single root and a single canal were included in the study. IRR cavities were created in the middle third of the root canal, and CH was placed. The samples were randomly divided into 4 groups (n = 15) according to the irrigation activation method to be tested: standard needle irrigation (SNI), sonic activation (EDDY), photon-induced photoacoustic flow (PIPS), and shock wave enhanced emission photoacoustic flow (SWEEPS). After irrigation activation applications, the root canals were obturated. Sections of 1.0 ± 0.1mm were taken from the apical, middle, and coronal regions of each sample. The penetration area (µm2) and maximum penetration depth (µm) of the root canal sealer were examined by CLSM and analyzed using ImageJ software. Statistical analysis was performed with a one-way ANOVA and post-hoc Tukey test at the P < 0.05 significance level. Among all irrigation activation methods tested, both the penetration area and maximum penetration depth of the root canal sealer were greater in the coronal region than in the apical region (p < 0.05). In the IRR region, there was no difference in terms of maximum penetration depth between PIPS and SWEEPS (p > 0.05), it was highest in SWEEPS (p < 0.05). PIPS and SWEEPS were better than other irrigation activation methods in the penetration of root canal sealer in the resorption areas of teeth with IRR.

Introduction/Objective. Calcium hydroxide (CH) is the medicament of choice in endodontic treatment of internal root resorptions. The aim of the study was to compare the effectiveness of three different techniques for CH removal from simulated internal root resorptions. Methods. Twenty-nine extracted single-root teeth were prepared using NiTi rotary files of BioRaCe system (40/.04) following irrigation. A round diamond drill was used in the making of a symmetrical standardized internal resorptions 6 mm from the apex. Three techniques for CH removal from internal resorptions were tested: modified conventional syringe irrigation (CSI), passive ultrasonic irrigation (PUI), XP-endo Finisher (XP). Resorptive cavities and apical thirds were observed under a stereomicroscope (?45) and scored (from 1 to 5), while representative samples were analysed by a scanning electron microscope. Obtained results were statistically processed by Kruskal?Wallis and Mann?Whitney U-test (p &lt; 0.05). Results. The most efficient system was PUI, with 66.7% of samples rated 1 and 33.3% rated 2. The next one was XP, and the least efficient was CSI, with 33.3% of samples rated 1 (resorptive defect without medicament). There was a statistically significant difference between the PUI and CSI systems (p &lt; 0.05), while there was no difference between the PUI and XP systems. Conclusion. No system completely removed the CH from the simulated internal root resorption cavities. PUI was the most effective system for removing CH. The combination of techniques provides better performance in removing CH paste residues from the canal walls

Objective: This study sought to evaluate the effect of conventional syringe irrigation (CSI), irrigation with XP-endo Finisher file (XP-F), passive ultrasonic irrigation (PUI), and photon-induced photoacoustic-streaming (PIPS) methods on dentine debris removal from teeth with simulated internal root resorption (IRR) cavities by using scoring and image analyzing methods. Materials and methods: Chemomechanical preparation of 88 single-rooted sample teeth was completed, they were split longitudinally and IRR cavities were prepared. Simulated debris was placed into the cavities. Four teeth were separated to serve as the negative control group. According to the final irrigation technique, 4 experimental groups were created (n = 20): Group 1, CSI; Group 2, XP-F; Group 3, PUI; and Group 4, PIPS. The amount of remaining debris in the IRR cavities was examined under a stereomicroscope. Analysis was performed using two different methodologies: (1) scoring method and (2) image analyzing method. The data were statistically evaluated by one-way analysis of variance, Kruskal-Wallis, chi-square, and Dunn tests with a significance level set as 5%. Results: In both methodologies, PIPS was found to be significantly more effective than XP-F in terms of debris removal. There was no significant difference between XP-F and PUI (p > 0.05). According to the findings obtained from the image analyzing method, PIPS and PUI groups were not significantly different (p > 0.05). Conclusions: PIPS method can be selected as an irrigation activation methodology in teeth with IRR. Considering the similar results of both evaluation methods, image analyzing programs can be used as an alternative in studies on debris removal.

Introduction:The purpose of this study was to compare the high resolution cone-beam computed tomography (CBCT) and standard mode CBCT diagnostic accuracy in internal root resorption with different sites and sizes. Methods and Materials:Eighty single rooted human teeth with visible pulps in periapical radiography were split mesiodistally along the coronal plane. Internal resorption like lesions were created in three areas (cervical, middle and apical) in labial wall of the canals in different diameters. High resolution CBCT (CBCT-H) and standard mode CBCT (CBCT-C) were taken from each tooth. Two observers examined the high resolution CBCT and standard mode CBCT to evaluate the presence of resorption cavities. The data were statistically analyzed and degree of agreement was calculated using Cohen’s kappa (k) values. Data were analyzed by SPSS 20 software and sensitivity, specificity and positive and negative predictive value for both methods were calculated. Data were analyzed using the Mac-Nemar and chi-square tests. Result:The positive predictive value and negative predictive value in CBCT-H was higher than that of CBCT-C, all of which indicates that the CBCT-H diagnostic test is more sensitive and more accurate than CBCT-C. Kappa statistics showed that there is a strong and complete agreement between the CBCT high resolution and reality (kappa: 0.72) and in the Standard CBCT method, a moderate agreement has been obtained with reality (Kappa: 0.45). Conclusion:According to our in vitro study CBCT high resolution has a higher diagnostic accuracy than conventional CBCT.

Objective: To evaluate the performance of conventional radiography and photostimulable phosphor (PSP) plate in the detection of simulated internal root resorption (IRR) lesions in early stages.Materials and methods: Twenty single-rooted teeth were X-rayed before and after having a simulated IRR early lesion. Three imaging systems were used: Kodak InSight dental film and two PSPs digital systems, Digora Optime and VistaScan. The digital images were displayed on a 20.1″ LCD monitor using the native software of each system, and the conventional radiographs were evaluated on a masked light box. Two radiologists were asked to indicate the presence or absence of IRR and, after two weeks, all images were re-evaluated. Cohen’s kappa coefficient was calculated to assess intra- and interobserver agreement. The three imaging systems were compared using the Kruskal–Wallis test.Results: For interexaminer agreement, overall kappa values were 0.70, 0.65 and 0.70 for conventional film, Digora Optima and VistaScan, respectively. Both the conventional and digital radiography presented low sensitivity, specificity, accuracy, positive and negative predictive values with no significant difference between imaging systems (p = .0725).Conclusions: The performance of conventional and PSP was similar in the detection of simulated IRR lesions in early stages with low accuracy.

Internal inflammatory root resorption is a relatively rare resorption that begins in the root canal and destroys surrounding dental hard tissues. Odontoclastic multinuclear cells are responsible for the resorption, which can grow to perforate the root if untreated. The initiating factor in internal root resorption is thought to be trauma or chronic pulpal inflammation, but other etiological factors have also been suggested. Active, expanding resorption requires vital pulp tissue and continuous microbiological irritation, likely from the necrotic coronal part of the root canal. In its classical form, internal root resorption is easy to diagnose. However, in many instances advanced diagnostic methods may be required for a definitive diagnosis. Internal root resorption is usually symptom free, but in cases of perforation, a sinus tract usually forms. The prognosis for treatment of small lesions of internal root resorption is very good. If, however, the tooth structure is greatly weakened and perforation has occurred, the prognosis is poor and tooth extraction must be considered. Sodium hypochlorite, ultrasonic instrumentation and calcium hydroxide are the cornerstones of treatment of internal inflammatory root resorption. Mineral trioxide aggregate is being increasingly used as a root canal filling material, particularly in cases of perforation.

This study aimed to evaluate the efficacy of passive ultrasonic irrigation (PUI) on dissolving the organic tissue inside simulated internal root resorption (IRR) using sodium hypochlorite (NaOCl) or chlorhexidine (CHX). A total of 40 human lower premolars were collected based on dimensional and morphological similarities. The roots were embedded in cylinders (3 cm diameter; 2.5 cm height) of self-cured acrylic resin, and then an IRR was simulated. The specimens were divided into 4 groups (n = 10) according to irrigation protocols: group 1: CHX + PUI; group 2: CHX; group 3: NaOCl + PUI; group 4: NaOCl. The total irrigation time was 150 s at a flow rate of 5 mL/min. A tissue mass of porcine palatine mucosa was used to simulate the organic tissue, it was weighed before and after the irrigation using an analytic balance, and the difference between both readings was calculated and transferred to percentage values. Data were submitted to statistical analysis using two-way ANOVA (factors: irrigant type and with/without PUI) and Tukey's test for multiple comparisons among the experimental groups (α = 0.05). There was a significant difference in both factors (irrigant: p=0.04; PUI: p ≤ 0.001). The groups that used PUI were more effective in dissolving the organic tissue of the IRR simulation than the groups without PUI. PUI is more effective than the syringe and needle irrigation in organic tissue dissolution.

This study aimed to compare the antibacterial efficacy of standard needle irrigation (SNI), EDDY, passive ultrasonic irrigation (PUI), photon-induced photoacoustic streaming (PIPS), and shock wave enhanced emission photoacoustic streaming (SWEEPS) activation on the teeth with simulated internal root resorption (IRR) and contaminated with Enterococcus faecalis (E. faecalis) using confocal laser scanning microscopy (CLSM) analyses. A total of 79 human maxillary central incisors with a single canal were selected. The canals were accessed, and then, the roots were split in the bucco-lingual direction. Artificial IRR cavities (depth of 0.8mm and a diameter of 1.6mm) were prepared using round burs and 20% nitric acid in the middle region of the root halves. The root halves were reconstructed with cyanoacrylate glue, and the canals were contaminated with a culture of E. faecalis for 30days. Root canal preparation was performed using the ProTaper Next rotary files up to X5 and 2.5% NaOCl irrigation. Teeth were randomly assigned to five groups according to the irrigation activation method (n = 15): SNI, EDDY, PUI, PIPS, and SWEEPS. The final irrigation procedures were performed using a total of 6mL of 2.5% NaOCl for each tooth with an activation time of 3 × 30s. The canals were stained with LIVE/DEAD BacLight dye and analyzed with CLSM to determine the percentages of dead bacteria in the biofilm. Two-way ANOVA and post hoc Tukey tests were used for statistical analysis (P < .05). None of the irrigation activation methods tested provided 100% bacterial elimination. There was no significant difference between the irrigation activation methods tested in terms of the percentage of dead bacteria (P > 0.05). In irrigation activation methods other than PIPS, there was no significant difference in the percentage of dead bacteria between the coronal, middle, and apical regions of the roots (P > 0.05). A higher percentage of dead bacteria was found in the middle region compared to the apical region in the PIPS (P < 0.05). Within the limitations of this study, SII, EDDY, PUI, PIPS, and SWEEPS have a similar antimicrobial effect on the teeth with IRR and contaminated with E. faecalis.

Abstract: Internal inflammatory root resorption (IIRR) is a rare, but significant consequence of dental trauma. Previous cases often focus on two-dimensional imaging. More widespread use of cone beam computed tomography (CBCT) has seen improved diagnostic accuracy of these defects leading to more appropriate management. In this case report, an adolescent male patient complained of a missing front tooth (UR1). Dental history revealed intrusive trauma to the predecessor as a child. The UR1 was impacted with a dilacerated root. CBCT imaging revealed severe internal root resorption, and due to its extensive nature, extraction was advised. CPD/Clinical Relevance: Readers should be aware of the consequences of internal inflammatory root resorption and understand the importance of early detection with appropriate special investigations.