Anomalous coronary circulation: left anterior descending and left circumflex coronary arteries arising from the right sinus of valsalva

Approximately 1% of adults who undergo cardiac catheterization have coronary anomalies. Patients may present with chest pain, arrhythmias, presyncope, and sometimes sudden cardiac death. Multidetector computed tomography (MDCT) is an excellent tool for identifying coronary artery anomalies and defining their course and relationship to the great vessels and surrounding structures; its value is incremental to conventional angiography. We present a rare case of a coronary anomaly involving three separate ostia at the right sinus of Valsalva for the left and right coronary vessels.     

Molecular imaging as a guide for the treatment of central nervous system disorders

Molecular imaging techniques have a number of advantages for research into the pathophysiology and treatment of central nervous system (CNS) disorders. Firstly, they provide a noninvasive means of characterizing physiological processes in the living brain, enabling molecular alterations to be linked to clinical changes. Secondly, the pathophysiological target in a given CNS disorder can be measured in animal models and in experimental human models in the same way, which enables translational research. Moreover, as molecular imaging facilitates the detection of functional change which precedes gross pathology, it is particularly useful for the early diagnosis and treatment of CNS disorders.This review considers the application of molecular imaging to CNS disorders focusing on its potential to inform the development and evaluation of treatments. We focus on schizophrenia, Parkinson''s disease, depression, and dementia as major CNS disorders. We also review the potential of molecular imaging to guide new drug development for CNS disorders.     

Novel imaging approaches in adult asthma and their clinical potential

Currently, imaging in asthma is confined to chest radiography and CT. The emergence of new imaging techniques and tremendous improvement of existing imaging methods, primarily due to technological advancement, has completely changed its research and clinical prospects. In research, imaging in asthma is now being employed to provide quantitative assessment of morphology, function and pathogenic processes at the molecular level. The unique ability of imaging for non-invasive, repeated, quantitative, and in vivo assessment of structure and function in asthma could lead to identification of ‘imaging biomarkers’ with potential as outcome measures in future clinical trials. Emerging imaging techniques and their utility in the research and clinical setting is discussed in this review.     

Mutagenicity and cytotoxicity in patients submitted to ionizing radiation: A comparison between cone beam computed tomography and radiographs for orthodontic treatment

Objectives:To evaluate and compare mutagenicity (micronucleus) and cytotoxicity (karyorrhexis, pyknosis, and karyolysis) in exfoliated buccal mucosa cells of children following cone beam computed tomography (CBCT) or conventional radiograph exposure necessary for orthodontic planning.Materials and Methods:A total of 49 healthy children were submitted to CBCT or a conventional orthodontic radiographic protocol; they were divided into two groups based on exam: CBCT (n  =  24) and Radiographic Set (n  =  25) groups. The micronucleus test in the exfoliated buccal mucosa cells was applied.Results:There was not a statistically significant difference (P > .05) found between the number of micronucleated buccal mucosa cells (MNC) before and after exposure to radiation in either group, showing that neither group experienced a mutagenic effect. However, radiation did cause other nuclear alterations closely related to cytotoxicity, including karyorrhexis, pyknosis, and karyolysis, in both groups (P < .05). The CBCT group presented a greater increase in cell death than was noted in the Radiographic Set group (P < .044).Conclusion:According to the micronucleus test, mutagenicity was not induced by the CBCT or the conventional radiographs, but cytotoxicity was verified after these exams, especially after CBCT. That might have happened once the CBCT group received a greater radiation dose than the Radiographic Set group as a result of the protocols used in orthodontic planning for this study.     

Retrieval of Extensive Gutta-percha Extruded into the Maxillary Sinus: Use of 3-dimensional Cone-Beam Computed Tomography

Introduction

Close proximity of the maxillary sinus to the roots of maxillary teeth can predispose to the inadvertent deposition of endodontic products into the maxillary sinus. One such material is thermoplasticized injectable gutta-percha, which has gained popularity of late. As a consequence of overfilling, some patients warrant surgical retrieval.

Methods

A case report of extreme overextension of gutta-percha within the maxillary sinus after endodontic retreatment on tooth #14 was provided. The distobuccal and palatal canals had been obturated with gutta-percha master cones and backfilled with thermoplasticized injectable warm gutta-percha. The mesiobuccal canal had only been filled with thermoplasticized injectable warm gutta-percha, the origin of the extrusion. Imagery with 3-dimensional cone-beam computed tomography was performed for localization of the gutta-percha.

Results

The patient underwent a Caldwell-Luc approach for removal of the extruded material. The gutta-percha was successfully removed intact, and the patient had an unremarkable postoperative course. However, the patient continues to have mild tenderness in the sinus region.

Conclusions

The featured case exemplified the consequence of overinstrumentation and ensuing inadequate apical stop. In these situations, the obturation of a maxillary tooth with thermoplasticized injectable gutta-percha, without master cones, can potentially result in overfilling and deposition into the antrum. Use of 3-dimensional cone-beam computed tomography could enhance endodontic diagnosis, serve as an aid for visualization of foreign materials within the sinus and contiguous soft tissue structures, and improve clinical outcome.     

Location and Dimensions of the Mental Foramen: A Radiographic Analysis by Using Cone-beam Computed Tomography

Introduction

The mental foramen (MF) is an important landmark in dentistry. Knowledge of its position is central to perform block anesthesia of the mental nerve or to avoid nerve damage during surgical procedures in the premolar area of the mandible. The present radiographic study aimed at evaluating the location and dimension of the MF and measuring distances to neighboring structures by using limited cone-beam computed tomography (CBCT).

Methods

Sagittal, axial, and coronal CBCT images of 142 patients (26 bilateral and 116 unilateral cases) were retrospectively screened to determine the location of the MF with respect to adjacent teeth and to take linear measurements of the size of the MF and its distances to the upper and lower borders of the mandible. In addition, the course and angulation of the mental canal exiting the MF were assessed.

Results

The majority of MF (56%) were located apically between the 2 premolars, and another 35.7% of MF were positioned below the second premolar. On average, the MF was localized 5.0 mm from the closest root of the adjacent tooth (range, 0.3–9.8 mm). The mean size of the MF showed a height of 3.0 mm and a length of 3.2 mm; however, individual cases showed large differences in height (1.8–5.1 mm) and in length (1.8–5.5 mm). All mental canals exiting the MF demonstrated an upward course in the coronal plane, with 70.1% of the mental canal presenting an anterior loop (AL) in the axial view. The mean extension of AL in cases with an AL was 2.3 mm.

Conclusions

This study is consistent with previous radiographic studies regarding size and location of MF and distances between MF and adjacent anatomic structures. The assessed bilateral cases showed a high intraindividual concordance for certain features when comparing right and left sides.     

Morphology of Mandibular First Molars Analyzed by Cone-beam Computed Tomography in a Korean Population: Variations in the Number of Roots and Canals

Introduction

The aim of this study was to determine the root and canal morphology of the mandibular first molars in a Korean population of Mongolian origin by retrospective analysis of a large number of cone-beam computed tomography (CBCT) images.

Methods

A total of 976 subjects with bilateral mandibular first molars were examined by using in vivo CBCT methods. The number and configuration of roots, the number of root canals, and the canal configuration based on Vertucci's classification were determined.

Results

Overall, 25.82% of examined molars had 3 roots, 73.51% had 2 roots, and 0.67% had 1 root. The incidence of fourth canal was 50.36%. A right-sided predominance was noted for extra distal roots (P < .001), whereas a left-sided predominance was observed for extra distal canals (P < .001). No significant sex-related differences were shown for their prevalence. The bilateral prevalence rate was 69.13% for extra distal roots and 78.08% for extra distolingual (DL) canals. In the mesial roots, type IV canal was the most frequent (76.86% for 2-rooted molars and 72.96% for 3-rooted molars). In the distal roots, type l was the most common (66.62% for 2-rooted molars and 99.40%–100% for 3-rooted molars). The incidence of 2 canals in distobuccal roots, first reported in this study, was 0.15%.

Conclusions

Among mandibular first molars, there is a high prevalence of a separate DL root and/or a separate DL canal, and such molars commonly have 4 canals in the Korean population. CBCT is a useful tool for determining root and canal morphology.     

Detection of Vertical Root Fractures in the Presence of Intracanal Metallic Post: A Comparison between Periapical Radiography and Cone-beam Computed Tomography

Introduction

This in vitro study compared cone-beam computed tomography (CBCT) exam with different voxel sizes with digital periapical radiography in the detection of vertical root fractures in teeth with and without intracanal metallic posts.

Methods

Eighteen single-rooted human teeth were endodontically treated, prepared for cast metal posts, and artificially fractured. After positioning the teeth in dry mandibular sockets, the samples were subjected twice (with and without posts) to digital periapical radiography at 3 different angles and to CBCT examinations with 2 voxel sizes, 0.125 and 0.25 mm. The images were evaluated by 3 oral radiologists. Indices of sensitivity, specificity, and positive and negative predictive values, in addition to the areas under the receiver operating characteristic curves (accuracy), were calculated. Comparison of the accuracy of the imaging methods was assessed by using the χ² test. Comparison of the accuracy between teeth with and without posts was determined by using the Fisher exact test.

Results

The accuracy of the imaging methods showed no significant differences (P = .08). The comparison between teeth with and without posts in each examination revealed significant differences for CBCT with a voxel of 0.125 mm (P = .04) and for periapical radiography (P = .04).

Conclusions

No significant differences were observed between CBCT and periapical radiography in the detection of vertical root fractures, except for teeth with metallic posts in images from CBCT with a voxel of 0.125 mm and in digital periapical radiography. Furthermore, voxel size did not significantly influence the diagnosis of vertical root fractures.     

Volumetric Changes in Apical Radiolucencies of Endodontically Treated Teeth Assessed by Cone-beam Computed Tomography 1 Year after Orthograde Retreatment

Introduction

Cone-beam computed tomography (CBCT) allows us to assess in 3 dimensions the location and size of periapical radiolucencies. We aimed to assess by CBCT scans the volumetric changes of periapical radiolucencies in endodontically treated teeth 1 year after orthograde retreatment.

Methods

Forty-five root-filled teeth with persistent apical periodontitis requiring endodontic orthograde retreatment from 37 individuals were included in the study. The research protocol was approved by the VU University Medical Center Amsterdam ethics committee (2007/265), and the participants signed a letter of consent. We made 2 CBCT scans for every patient, the first one before retreatment and the second one a year later. Two observers measured independently the volume of radiolucencies on CBCT images by using the AMIRA software. The intraclass correlation coefficient was used to evaluate interobserver agreement, and the Wilcoxon signed rank test was used to assess pretreatment and post-treatment volume size.

Results

The intraclass correlation coefficients were 0.994 and 0.998 for the scans before retreatment and 1 year after, respectively. The recall rate was 78% for the teeth and 73% for the patients. The volumetric change in periapical radiolucencies 1 year after retreatment was statistically significant (z = −3.112, P < .005). The volume of periapical radiolucencies reduced in 20 teeth (57%), remained unchanged in 8 (23%), and increased in 7 (20%).

Conclusions

One year after endodontic orthograde retreatment, the volume of periapical radiolucencies reduced significantly in 57% of the teeth.