Diagnostic Accuracy of Different Resolutions of Cone Beam Computed Tomography Imaging System for Detection of Vertical Root Fractures In Presence of Casting Posts

Objective: The diagnosis of vertical root fracture (VRF) in endodontically treated teeth is a clinical challenge due to lack of specific clinical and radiographic signs. Although radiographic evaluation such as CBCT is helpful, intracanal posts can produce artifacts and may impair the quality of CBCT scans. This study aimed to compare the diagnostic accuracy of different resolutions of CBCT in detection of VRF in roots with casting post.Methods: Eighty extracted human premolars were under went routine endodontic procedure and cast posts were subsequently prepared. The teeth were randomly divided into two groups. The fracture lines were induced by an Instron machine in test group, while the teeth in control group had no fracture. The teeth were scanned by CBCT with two voxel resolution protocols (0.15mm  and 0.2mm). Three observers assessed the scans for presence of VRF on a 5-point scale. Diagnostic accuracy indices were estimated and the difference were analyzed with the Mann-Whitney test (p<0.05).Results: Probabilistic sensitivity for 0.15mm and 0.2mm resolution was 59.16 (5.2) and 46.66 (16.64), respectively. Furthermore, probabilistic specificity for 0.15mm resolution was 56.16 (15.21) and for 0.2mm was 61.66 (8.77).There were no statistical differences between different resolutions  in all diagnostic values including sensitivity, specificity, positive and negative predictive values (p>0.05).Conclusion: Diagnostic ability of CBCT in presence of casting posts was not influenced by system resolution. According to ALARA principle, 0.2mm voxel resolution protocol is recommended in these cases

Cone-Beam Computed Tomographic Assessment of Anatomical Variations of the Interforaminal Region in a Selected Iranian Population

Objectives This study assessed the anatomical variations of the mental foramen (MF) and presence and length of the anterior loop and the incisive canal in a selected Iranian population using cone-beam computed tomography (CBCT). Methods This descriptive, cross-sectional study evaluated CBCT scans of 256 patients (123 males, 133 females) over 18 years of age. The CBCT multiplanar reformatted panoramic images (10-mm thickness) were used to assess the anatomical position of the MF and presence/absence and length of the anterior loop. The cross-sectional images were used to assess the presence/absence and length of the incisive canal. The anatomical variations were compared in the right and left sides and between males and females using dependent and independent t-test. SPSS version 21was used for statistical analysis. Results The most common position of MF was adjacent to the apex of the second premolar, noted in 41.4% of the patients. The second common position of MF was between the apices of the first and second premolars (30.1% of the patients). The anterior loop was present in 44.3% of the patients. The mean length of the anterior loop and the incisive canal was 2.64 mm and 7.15 mm, respectively. No significant difference was noted between males and females or right and left sides in any variable (P>0.05). Conclusion Anatomical variations of the anaterior mandible indicate the significance of 3D imaging to prevent nerve traumatization by proper treatment planning

Comparison of Diagnostic Accuracy of Cone Beam Computed Tomography and Digital Radiography for Detection of Vertical Root Fractures with and without Gutta Percha

Objective: Diagnosis of vertical root fractures (VRFs) is critical in endodontics; which most of the times occurs in endodontically treated teeth with root canal fillings such as gutta percha. Despite Cone Beam Computed Tomography (CBCT) has significantly enhanced image quality compared to digital radiography (DR) which aid the diagnosis, artifacts has remained as a problem in VRF detection. The aim of this study was to compare accuracy of CBCT and digital radiography system in vertical root fracture with presence and absence of gutta-percha.Methods: In this experimental in vitro study, 60 premolar teeth were cut at the cementoenamel junction .The teeth were randomly divided into two groups; for one group root canal therapy was done and the roots filled with gutta-percha. The other group was the control one .At the first stage CBCT scan and digital radiography was done and subsequently, vertical root fractures were induced for all samples. Then all the teeth were scanned by CBCT and digital radiography system and three observer assessed CBCT images and digital radiographies for presence of vertical root fracture. ANOVA and weighted Kappa tests estimated the diagnostic accuracy values and inter-observer agreement.Results: All values for CBCT were higher than Digital radiography except for absolute specificity and negative predictive value (p=0.409, p=0.053). In both imaging systems, there was no statistical difference between presence and absence of gutta-percha. (p=0.599, p=1.000, p=0.673, p=0.373).Conclusion: Diagnostic accuracy of vertical root fracture was not influenced by presence or absence of gutta-percha. Additionally, CBCT imaging system had higher diagnostic accuracy in comparison of digital radiography

The Effect of Intra-Canal Posts on Diagnostic Accuracy of Cone Beam Computed Tomography and Digital Radiography in Detection of Vertical Root Fractures

Objective: Diagnosis of vertical root fractures (VRFs) is critical in endodontics. Cone Beam Computed Tomography (CBCT) has significantly enhanced image quality compared to digital radiography (DR) and greatly aids the diagnosis of VRFs but, metal artifacts has remained as a problem in VRF detection. This study evaluated the effect of intra canal posts on the diagnostic accuracy of CBCT and DR for detection of VRFs.Methods: In this experimental in vitro study eighty extracted human premolar teeth were cut at the cement-enamel junction .After root canal preparation, the casting posts were made. Samples were randomly divided into 2 groups of 40; group one with induced fracture and group 2 as the control group. Radiographs were taken for all specimens with and without posts with both imaging systems. Three observers assessed the presence or absence of VRF. Accuracy of the two imaging systems and the effect of post on VRF detection were assessed, using two-way ANOVA test and inter observer coefficient agreement was calculated.Results: Absolute diagnostic sensitivity and specificity of CBCT and absolute sensitivity of DR in the group with intracanal posts were significantly lower than those in the group without posts (p=0.023, p=0.034 and p=0.034 respectively). Absolute specificity of DR in the group with posts was significantly higher than that of the CBCT (p=0.014). The absolute and complete specificity of CBCT in the group without posts was significantly higher than those of DR (p=0.024, p=0.04). No statistically significant difference was found in inter observer agreement coefficient in presence or absence of posts or between the two imaging systems (p=0.119).Conclusion: Intra canal posts decreased the diagnostic accuracy of CBCT and DR for detection of VRFs and this reduction was greater in CBCT. However, absolute specificity of DR in the group with posts was significantly higher than that of the CBCT, where as CBCT images of teeth without posts still had higher diagnostic accuracy than DR

Diagnostic Accuracy of Digitized Images Using Different Resolution Settings of Digital Camera in Detection of Proximal Caries

Objective: When none of digital systems and scanners is accessible and it is essential to have digitized images of conventional radiographs, digital cameras can be used. The Aim of this study  was to investigate whether digital images obtained by different resolutions of a digital camera are matched to the original radiographs in evaluation of caries.Methods: In this diagnostic accuracy in vitro study the conventional radiographs of168 proximal surfaces of 84 teeth were produced, Then they were digitized with digital camera in three different resolutions; high (2048x1536), medium (1600x1200) and low resolution (480x460). Images were stored in Photoshop7.0 software, and were evaluated by5 observers to show the presence and depth of the caries. Cronbach’s α calculated inter-observers agreement and in order to calculate the agreement with original conventional radiographs Kappa index was used.Results: In assessing the presence of caries, the agreement between low, medium and high resolutions with original radiographs were 0.286, 0.235 and 0 respectively. Also, assessing the depth of the caries agreement was reported0.21, 0.338 and 0.412 respectively. In most instances, there was a fair agreement between the different resolutions and original radiographs. The highest inter- observer’s agreement was reported in diagnosis of the presence of the caries with using high resolution (α=0.837) and the lowest inter-observer’s agreement was reported in diagnosis of the  depth of the caries with medium resolution (α=0.762).There was no significant difference reported in observations of different resolutions and original images.Conclusion: Using of high-resolution cameras did not show a significant difference with medium and low resolutions in caries evaluations. Therefore, considering the increase in the file size and difficulties in cameras selection, using of high-resolution digital cameras is not necessary in order to increase the diagnostic accuracy of digitized images

Dimensional Distortion of Four Types of Intracanal Posts on CBCT Scans with Different Fields of View and Resolutions

Objectives This study assessed the dimensional distortion of four types of intracanal posts on cone-beam computed tomography (CBCT) scans with two different fields of view (FOV) in high and standard resolution modes. Methods This in vitro study evaluated 40 extracted single-rooted maxillary central incisors that underwent root canal treatment. The teeth were randomly assigned to 4 groups (n=10) for placement of non-tapered brass, silver, titanium and stainless steel (SS) intracanal posts. The diameter of the posts was measured at two reference points by a digital caliper (gold standard). The teeth underwent CBCT with 8 x 8 and 8 x 12 cm FOV with high and standard resolution modes. The post diameters were measured on axial CBCT images at the same reference points and compared with the gold standard. Data were analyzed by ANOVA, and paired and independent sample t-test. Results Significant differences were noted between the radiographic diameter of the posts and their actual size (P<0.05). Titanium posts (40.25%) showed minimum percentage of dimensional distortion followed by brass (54%), silver (62.5%) and SS (70.17%) posts. High-resolution images with 8 x 8 cm FOV yielded minimum dimensional distortion (40.6%) followed by high-resolution images with 8 x 12 cm FOV (45.75%), standard-resolution images with 8 x 8 cm FOV (68.75%), and standard-resolution images with 8 x 12 cm FOV (72.1%). Conclusion All metal posts showed significant dimensional distortion on CBCT scans, irrespective of the FOV size and resolution mode. SS posts yielded maximum, and titanium posts showed minimum dimensional distortion

Evaluation of Posterior Superior Alveolar Canal on Cone Beam Computed Tomography Images

Objectives The posterior superior alveolar artery (PSAA) is one of the branches of the maxillary artery that is located on the lateral wall of the maxillary sinus. The aim of the present study was to evaluate the detectability, position, and diameter of the posterior superior alveolar (PSA) canal and its relationship with the alveolar ridge using cone-beam computed tomography (CBCT).Methods A total of 257 CBCT images were evaluated. The PSA canal location was categorized into three forms of intra-osseous, below the membrane, and on the outer cortex of the lateral sinus wall. The distance between the lower border of the artery and the alveolar crest, the distance between the artery and the medial wall of the sinus, and the diameter of the artery were all measured. The prevalence of sinusitis and mucous retention cyst was also determined. The Chi-square test and independent t-test were used for statistical analysis.Results The most common type of PSA canal was intra-osseous, followed by beneath the mucosal membrane and on the outer cortex of the lateral sinus wall. The lowest distance between the PSA canal and medial sinus wall and ridge crest, and canal diameter were higher in males (P<0.05). In addition, sinus pathologies were significantly more common in males than females (P<0.05).Conclusion The most common type of PSA canal was intra-osseous, and the distances between the lower border of the canal and the alveolar crest and ridge height decreased with aging; thus, it should be considered during implant surgery

Diagnostic Accuracy of Cone Beam Computed Tomography in Identification of Foreign Bodies in the Head and Neck Region

Objectives This study aimed to assess the identification of traumatic foreign bodies in the head and neck region using cone-beam computed tomography (CBCT).Methods In this study, samples (1×1×0.1 cm) were fabricated from 6 different types of materials commonly found in various head and face traumas. These materials included iron, glass, stone, wood, asphalt, and tooth. They were located in 3 different areas, including the tongue, airway, and vestibule of 3 sheep heads. Ten scans were acquired from these materials embedded in different regions. A total of 180 images were analyzed by 2 observers and rated in terms of visual clarity of the foreign body. The results were analyzed by the Kruskal-Wallis test.Results In 100% of images, stone, asphalt, and glass were observed in all 3 areas with high resolution. On the other hand, 100% of images were unclear in all evaluated areas with metal artifacts. Tooth images were found to be excellent in 100% of cases in the muscle and airway regions and 80% of cases in the vestibule region (unclear in 20% of cases). However, wood was not detected in 100% of images from the tongue and vestibule regions. It was not detected on 60% of images from the airway, while it was found on 40% of images with low resolution.Conclusion CBCT detected and located all opaque objects such as iron, glass, stone, asphalt, and tooth. However, it showed limited potential in detecting radiolucent objects such as woo

Comparative Diagnostic Accuracy of VistaCam IX Proxi and Bitewing Radiography for Detection of Interproximal Caries

Statement of the Problem: Early detection of caries and the extent of carious lesions for appropriate treatment planning are very important and lead to introduction of new diagnostic tools.Purpose: This study aimed to compare the diagnostic accuracy of VistaCam IX Proxi and bitewing radiography for detection of posterior interproximal caries.Materials and Method: This in vitro study was performed on 40 extracted posterior teeth without cavitated carious lesions. Bitewing radiographs were obtained, infrared (IR) examination was performed, and the teeth were sectioned for histopathological analysis under a stereomicroscope as the gold standard for detection of caries and determination of the extent of carious lesions. Data were analyzed with Cohen’s kappa statistic, and Wilcoxon rank sum test.Results: The specificity of VistaCam IX Proxi and bitewing radiography was 71.4% and 87.7%, respectively. Their sensitivity was 100% and 40% for enamel caries, 72.8% and 54.5% for external half dentin caries, and 82.3% and 58.8% for internal half dentin caries, respectively (p= 0.048).Conclusion: Bitewing radiography had a higher specificity and lower rate of false positive results. However, VistaCam IX Proxi had higher sensitivity for caries detection with lower rate of false negative results. Considering the higher sensitivity and significantly lower frequency of false negative results by VistaCam IX Proxi, it may be reliably used for caries detection specially enamel caries, and can serve as an adjunct to bitewing radiography

Accuracy of digital subtraction radiography in combination with a contrast media in assessment of proximal caries depth

Background and aims. Radiography is used to diagnose the demineralization process and carious lesions; however, conventional radiography and direct digital images do not show these lesions when the amount of demineralization is less than 40%. Digital subtraction radiography has recently been used to improve the diagnostic quality of these lesions. The purpose of this study was to compare the caries depth estimated by digital subtraction radiography in combination with barium sulfate in diagnosing proximal dental caries with histopathologic evaluation.
 Materials and methods. In this study 30 molars and premolars (24 demineralized lesions with cavity, 8 without cavity) were studied. Direct digital images were taken (kVp: 68, mA: 8; t: 0.12 for premolars and t: 0.16 for molars) whereas the position of X-ray tube and CCD receptor and teeth was fixed. To prepare the second images 135 gr/L barium sulfate was used. The images obtained with the same exposure and geometry and then subtracted. The depth of the lesions in direct digital and subtracted images were assessed and compared with the depth measured in histopathologic assessments.
 Results. The mean depths (± SD) of the lesions were 1.80 ± 0.77 mm in direct digital radiography, 2.32 ± 0.76 mm in subtracted images after barium sulfate treatment, and 2.51 ± 0.43 mm in histopathologic sections. The statistical difference between direct digital radiography and the other methods was significant (P < 0.05). However, the differences were not statistically significant between subtracted images and histopathologic sections. The average intra-class correlation coefficient was 0.7241 (CI: 95%).
 Conclusion. The present study has demonstrated that digital subtraction radiography images have the potential to measure the depth of proximal caries with no significant difference with histopathologic evaluation