Impact of dental imaging on pregnant women and recommendations for fetal radiation safety: A systematic review.

Purpose: This study was conducted to investigate the safety of dental imaging in pregnant women with respect to fetal health. Materials and Methods: Searches were conducted of the PubMed, Scopus, and Web of Science databases in May 2023. The inclusion criteria encompassed cross-sectional and longitudinal studies that focused on the analysis of diagnostic dental imaging in pregnant women, as well as studies utilizing phantoms to simulate imaging examinations. The exclusion criteria consisted of reviews, letters to the editor, book chapters, and abstracts from scientific conferences and seminars. Results: A total of 3,913 articles were identified. Based on a review of the titles and abstracts, 3,892 articles were excluded, leaving 21 articles remaining for full-text review. Of these, 18 were excluded, and 4 additional articles were included as cross-references. Ultimately, 7 articles underwent quantitative-qualitative analysis. Three retrospective studies were focused on pregnant women who underwent dental imaging procedures. The remaining 4 studies utilized female phantoms to simulate imaging examinations and represent the radiation doses absorbed by the uterus or thyroid. Conclusion: Few dental radiology studies have been conducted to determine the safe radiation threshold for pregnant women. Additionally, the reviewed articles did not provide numbers of dental examinations, by type, corresponding to this dose. Dental imaging examinations of pregnant women should not be restricted if clinically indicated. Ultimately, practitioners must be able to justify the examination and should adhere to the "as low as diagnostically acceptable, being indication-oriented and patient-specific" (ALADAIP) principle of radioprotection.

The interference of digital radiographic image acquisition and processing protocols in the diagnosis of incipient enamel carious lesions.

Background: This study aims to evaluate the diagnosis of proximal carious lesions through different parameters of execution and visualization of the images. Material and Methods: Proximal carious lesions were artificially induced in human teeth three different times (10, 20, and 30 hours) by in vitro demineralization. The teeth were radiographed with the Dürr digital system using three exposure times (0.10, 0.16, and 0.20s) and three different resolutions in the scanning of the phosphor plates (20-, 25- and 40-line pairs). After acquiring the images, they were submitted to VistaScan Fine, Caries 1, and Caries 2 software filters. Three radiologists analyzed the images in JPEG format. Results: The Pearson's chi-square test showed an association between longer demineralization time and the presence of injury according to the professional's classification. There was no statistically significant association among the other parameters, exposure time, resolution, and use of filters and the presence of a lesion. All parameters showed a greater sensitivity than specificity. The exposure time of 0.2s showed better accuracy, the resolutions 25 and 40lp showed equal results and better than 20lp and the Fine filter obtained better values than the Caries 1 and 2 filters. Conclusions: Despite the variation of parameters, exposure time, resolution, and use of filters, there were no statistically significant differences. For better diagnostic accuracy, it is recommended to use 0.2s of exposure time and a Fine filter, and scan the phosphor plates with 25lp. Key words:Orbital fracture, Etiology, Orbital trauma, Road traffic accidents, Trauma.

Comparative study of cranial measurements between sexes from Brazil and The Netherlands: A cone-beam computed tomography study.

The objective of this study was to better understand human variation by comparing cone-beam computed tomography-based cranial measurements between both sexes of individuals from two distinct populations: Brazilian and Dutch. Cone-beam computed tomography volumes of 311 patients between 20 and 60 years from Brazil and The Netherlands were selected. Two radiologists performed 16 linear measurements in the maxillary sinuses and mandibular canal. Kruskall-Wallis test compared measurements of the two cranial structures between male and female for the two populations and four age ranges (20-30, 31-40, 41-50, 51-60). Mann-Whitney test compared individual measurements obtained from the cranial structures between male and female for each population, and between both populations for both sexes. Intra- and inter-observer reliability was assessed by intraclass correlation test (α = 0.05). No significant differences were found in the linear measurements among the experimental groups including sex, population and age group for both cranial structures (p > 0.05). Most of the cranial linear measurements were significantly higher for male than those for female irrespective of the population (p ≤ 0.05). When the populations were compared regardless of sex, Brazilians presented four significantly higher measurements, and Dutch presented seven significantly higher measurements (p ≤ 0.05). The assessed cranial structures did not differ between Brazilian and Dutch populations for both sexes and four age ranges. Multiple linear measurements differed between both populations with a predominance of larger dimensions for the Dutch population.

Validation and comparison of volume measurements using 1 multidetector computed tomography and 5 cone-beam computed tomography protocols: An in vitro study.

Purpose: The purpose of this study was to compare volume measurements obtained using 2 image software packages on Digital Imaging and Communications in Medicine (DICOM) images acquired from 1 multidetector computed tomography and 5 cone-beam computed tomography devices, using different protocols for physical volume measurements. Materials and Methods: Four pieces of bovine leg were prepared. Marrow was removed from 3 pieces, leaving cortical bone exposed. The resulting space of 1 piece was filled with water, another was filled with propylene glycol, and the third was left unfilled. The marrow in the fourth sample was left fully intact. Volume measurements were obtained after importing DICOM images into the Dolphin Imaging 11.95 and ITK-SNAP software programs. Data were analyzed using 3-way analysis of variance with a generalized linear model to determine the effects of voxel size, software, and content on percentage mean volume differences between tomographic protocols. A significance level of 0.05 was used. Results: The intraclass correlation coefficients for intraobserver and interobserver reliability were, respectively, 0.915 and 0.764 for the Dolphin software and 0.894 and 0.766 for the ITK-SNAP software. Three sources of statistically significant variation were identified: the interaction between software and content (P=0.001), the main effect of content (P=0.014), and the main effect of software (P=0.001). Voxel size was not associated with statistically significant differences in volume measurements. Conclusion: Both content and software influenced the accuracy of volume measurements, especially when the content had gray values similar to those of the adjacent tissues.

Association between internal carotid artery calcifications detected as incidental findings and clinical characteristics associated with atherosclerosis: A dental volumetric tomography study.

PURPOSE: To evaluate the presence of calcifications in the internal carotid artery (ICA) in cone-beam computed tomography (CBCT), and to verify the association of these findings with sex, age, dental condition, and risk factors associated with vascular disorders. METHODS: The CBCT scans used in this study were obtained from the database of a private dental clinic requested for the planning of rehabilitation with dental implants. The selection criteria were patients aged 40 years and above. Out of a pool of 1176 CBCT examinations, a total of 284 scans of adult patients were evaluated by two blinded observers. Data were collected from patients' medical records. RESULTS: ICA calcifications were present in 63.0% of the examinations. Most calcifications were in the intracranial pathway (166). Despite being present in a smaller number 57 (C1), extracranial calcifications were more severe. Spearman's ρ coefficients (rS) indicated that the number of missing teeth was directly associated with the presence of calcifications (p = 0.042) and severity (p = 0.020). The age variable also had a direct relationship with the presence of calcifications (p ≤ 0.0001), increasing its frequency and severity over the years. In addition, hypertension (p = 0.036) and use of antihypertensive drugs (p = 0.015) were directly associated. CONCLUSIONS: There is a high occurrence of ICA calcifications in CBCT as incidental findings in adult patients, and it is directly associated with age, number of missing teeth and hypertension.

The imaging role for diagnosis of idiopathic osteosclerosis: a retrospective approach based on records of 33,550 cases.

OBJECTIVE: The study aimed to describe the diagnostic imaging features of idiopathic osteosclerosis (IO) to aid in differential diagnosis of similar dentomaxillomandibular conditions. MATERIALS AND METHODS: An archive of 550 dentomaxillofacial radiographic (panoramic radiography (PR) and cone beam computed tomography (CBCT)) images and 33,000 histopathological records were reviewed to identify IO cases. Chi-square, Student's t test, and ANOVA tests, with a significance of p < 0.05, were applied for comparative analysis. In addition, we analyzed various studies to present a short review. RESULTS: After meticulous observation, 36 images of 34 patients revealed 60 IO lesions in 31 PR and 5 CBCT. Sex, age group, anatomical site, shape, regularity, and root relationship showed statistical significance: sex and age group (p = 0.046), sex and IO regularity (p = 0.007), age group and IO regularity (p = 0.014), anatomical site and IO shape (p = 0.010), anatomical site and IO regularity (p = 0.003), and IO shape and IO regularity (p = 0.002). We presented a short review from 26 articles, including retrospective, cross-sectional, and longitudinal studies, documenting 2307 patients with 2435 IO lesions from 51,160 imagiological examinations. CONCLUSIONS: A radiographic diagnostic profile of IO may guide the clinical practitioners in differentiating an incidental radiopacity. PR is a preliminary examination, with CBCT facilitating the IO diagnosis. CLINICAL RELEVANCE: Knowledge of imaging characteristics variability of idiopathic osteosclerosis is crucial for accurate diagnosis process when incidental radiopacities are found in the panoramic radiographs, thus avoiding unnecessary biopsies. CBCT scans facilitate the interpretation of idiopathic osteosclerosis overlapping the mandibular canal.

Diagnostic efficacy of different cone beam computed tomography scanning protocols in the detection of chemically simulated external root resorption.

OBJECTIVES: The aim of this study was to evaluate the efficacy of different high-resolution cone beam computed tomography protocols in the diagnosis of chemically simulated external root resorption (ERR). STUDY DESIGN: ERR was simulated in 3 sizes by using an acid decalcification protocol in the cervical, middle, and apical thirds of 30 single-rooted premolars. Four scans of each tooth were acquired with different voxel sizes: 0.080, 0.085, 0.120, and 0.133 mm. The images were analyzed by 2 blinded evaluators for the presence of ERR. The evaluation of diagnostic performance was based on receiver operating characteristic (ROC) curve analysis. RESULTS: No statistically significant differences were found in the detection of ERR with regard to lesion sizes or the different root thirds. Areas under the ROC curve were 0.901, 0.892, 0.887, and 0.767 for voxel sizes of 0.080, 0.085, 0.120, and 0.133 mm, respectively. Voxel sizes of 0.080 and 0.085 mm presented significantly larger areas under the ROC curve compared with the voxel size of 0.133 mm. There were no statistically significant differences among the protocols with the use of voxel sizes of 0.080, 0.085, and 0.120 mm. CONCLUSIONS: Cone beam computed tomography examinations with higher-resolution protocols demonstrated better performance in the diagnosis of ERR. Further investigations using simulations that more closely resemble the actual ERR process are warranted.

Imaging Factors Impacting on Accuracy and Radiation Dose in 3D Printing.

OBJECTIVES: To compare reconstructed area and surface roughness of 3D models acquired using nine image acquisition protocols. Radiation dose was also compared among acquisition protocols. METHODS: A dry craniofacial specimen was scanned using three CT devices (a cone beam CT, a 16-channel fan beam CT, and a 64-channel fan beam CT), with three different acquisition protocols each. Nine 3D models were manufactured using polylactic acid. Surface roughness and reconstructed area were determined for each 3D model. The radiation dose during acquisitions was measured using lithium crystals. ANOVA was used to compare the data among the 3D models. Linear function optimization techniques based on stochastic variables were applied to identify the most suitable protocol for use. RESULTS: For surface roughness, statistically significant differences were observed among all 3D models and the specimen. For reconstructed area, CBCT and one CT-16 channel protocols originated 3D models statistically significant different from the specimen. Higher radiation doses were observed with fan beam CT acquisitions. CONCLUSIONS: All three CT devices were suitable for 3D printing when used at full resolution. The highest reconstruct area vs. radiation dose ratio was found for 64-channel CT devices.

Is cone beam computed tomography accurate for postoperative evaluation of implants? An in vitro study.

OBJECTIVE: The aim of this study was to evaluate the accuracy of cone beam computed tomography (CBCT) for evaluation of the bone-implant interface in comparison with periapical radiography. STUDY DESIGN: Titanium implants were inserted in 74 bovine rib blocks in intimate contact with bone walls and with a gap of 0.125 mm (simulating failure in the osseointegration process). Periapical radiographs were taken with conventional film, and CBCT scans were acquired with i-CAT (0.2 mm and 0.125 mm voxel) and Kodak (0.2 mm and 0.076 mm voxel) units. Three examiners evaluated the images using a 5-point scale. Diagnostic accuracy was analyzed through sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC) with 95% confidence intervals (CIs). Intra- and interexaminer agreements were analyzed through Kendall's concordance test. RESULTS: Intra- and interexaminer agreements showed satisfactory results. The greatest accuracy was observed with conventional radiography (AUC = 0.963; CI 95% = 0.891-0.993). I-CAT 0.125-mm images showed good accuracy (AUC = 0.885; CI 95% = 0.790-0.947), with no significant difference compared with conventional radiography. Kodak images had high specificity and low sensitivity, presenting more false-negative results. CONCLUSIONS: Conventional radiography showed the highest accuracy for assessment of the bone-implant interface. However, CBCT (i-CAT; 0.125-mm voxel), if available or if performed for preoperative assessment of another implant site, may provide similar accuracy.

Validation study of a new method for sexual prediction based on CBCT analysis of maxillary sinus and mandibular canal.

OBJECTIVE: The aim of this study was to evaluate the accuracy of two craniometric methods for sexual prediction (SP) using cone-beam computed tomography (CBCT) in the Dutch population and to construct a formula for each method and then the two combined. DESIGN: One-hundred sixty CBCT images were selected from a Dutch database (80 males and 80 females). The images were analyzed by two examiners taking seven measurements in the maxillary sinus (MS) region (first method) and nine in the mandibular canal (MC) region (second method). The most predictive measurements in both methods were used to develop an equation to determine the accuracy of each method. RESULTS: All measurements showed statistical difference between genders. Logistic regression results showed two variables with greater SP index with 75% accuracy in the first method and four variables with 71.9% accuracy in the second. The two methods combined showed another four variables with 78.5% accuracy. CONCLUSION: All measurements showed statistically significant differences between sexes. The SP accuracy values were 75% for first 71.9% for the second method. When the two methods were combined, the accuracy increased to 78.5%. The formulas developed in this study can be applied as a complementary method for human identification in the Dutch population.

Development of a new in vitro methodology to simulate internal root resorption.

INTRODUCTION: Studies to evaluate the diagnostic power of imaging examinations to detect root resorption have been based on simulations produced by burs. Standardized, round, and well-outlined access cavities do not reproduce the characteristics of physiological lesions and may facilitate diagnosis, masking the true accuracy of imaging techniques. A methodology to simulate internal root resorption by using acid demineralization was developed. METHODS: Eleven extracted single-rooted teeth were mesiodistally sectioned into homologous halves. Root canals were labeled to ensure restricted and controlled action of fluids. The protocol was composed of 24-hour cycles (5% nitric acid for 12 hours, rinsing with deionized water, and 8% sodium hypochlorite for 10 minutes). At the end of each cycle 1 tooth was removed from treatment, defining an exposure time that cumulated to the last tooth. Electron microscopy imaging was assessed to determine lesion area and depth. RESULTS: Minimum and maximum and areas and depths were 3.14 mm² and 10.34 mm² and 0.22 mm and 1.59 mm, respectively. Resorption simulated by the protocol proposed reproduced lesions of different sizes. CONCLUSIONS: The irregular shape and larger diameter:depth ratio suggest that these lesions are more similar to in vivo internal root resorption, compared with bur-induced lesions.

Detection of vertical root fractures by conventional radiographic examination and cone beam computed tomography - an in vitro analysis.

OBJECTIVES: This study compared the ability of conventional radiographic and cone beam computed tomography (CBCT) examinations to detect vertical root fractures (VRF) in teeth with or without root canal treatment and metallic posts. Furthermore, the influence of using different voxel sizes from CBCT images was assessed. METHODOLOGY: Sixty single-rooted human teeth were randomly divided into two groups: experimental and control. Twenty teeth were endodontically prepared and obturated with gutta-percha, twenty had a metallic postcemented after the filling, and twenty had no preparation. The teeth from the experimental group were fractured. All teeth were radiographed with three different horizontal angles, and after, CBCT images were acquired following three protocols in which the variation was the voxel resolution (0.4, 0.3, and 0.2 mm). Three calibrated examiners assessed the images. RESULTS: Chi-squared test showed no statistical difference among the images in detecting VRFs. The results of the diagnostic performance tests presented similar ability to detect VRFs when conventional radiographic examination was compared with 0.2 and 0.3-voxel CBCTs scans, in roots without endodontic treatment and metallic post. Moreover, specificity, sensitivity, and accuracy findings were similar for both 0.2 and 0.3-voxel resolution scans for teeth that are not root filled. However, it was observed that in teeth with root canal treatment and a post, the accuracy was higher when 0.2-mm voxel resolution was used. CONCLUSION: The radiographic examination with horizontal angle variation should be encouraged as the first complementary approach to assess the presence of VRFs. If conventional imaging is not capable to provide adequate information, CBCT can be indicated if a root fracture is strongly suspected. The root condition should then guide the voxel resolution choice, selecting 0.3-voxel for not root filled teeth and 0.2-voxel for teeth with filling and/or a post.

Comparison between two tomographic sections in the diagnosis of external root resorption.

OBJECTIVES: To assess the accuracy of coronal and sagittal CT sections to detect cavities simulating root resorption. MATERIAL AND METHODS: 60 mandibular incisors were embedded in plaster bases, and cavities with 0.6, 1.2 or 1.8 mm in diameter and 0.3, 0.6 or 0.9 mm in depth (small, medium and large cavities) were drilled on the buccal surfaces with high-speed round burs with diameters of 0.6, 1.2 and 1.8 mm to simulate external inflammatory root resorption. Simulations in the cervical, middle and apical thirds of each tooth root were made randomly. The Dental Scan software was used to obtain 1-mm-thick axial images from direct scanning, which were reconstructed in the coronal and sagittal planes using 3D software (Syngo FastView). Each series was loaded into the software. Fourteen images of each tooth were reconstructed in the coronal plane and 14 in the sagittal plane. A total of 1,652 images were obtained for analysis. Series information, tooth number and the plane reconstructed were stored. The images generated were saved on a CD-ROM together with the visualization software (Syngo FastView). Images were analyzed by a previously calibrated blinded, radiologist. Cochran's Q test was conducted separately for each region analyzed followed by pair-wise comparison by the McNemar test (p=0.05). RESULTS: No statistically significant difference (p>0.05) was observed in the diagnosis of simulated resorption between the apical, middle, and coronal thirds. When the axial plane was assessed separately, diagnoses were statistically different (p<0.05) among the three root thirds. The apical third differed significantly (p<0.05) from the cervical and middle thirds. Diagnostic errors were more often observed in the apical third compared to the cervical and middle thirds. Mid-sized cavities revealed no statistically significant differences (p>0.05) between planes, irrespective of the third in which the resorptions were located. CONCLUSION: When tomographic sections are requested for the diagnosis of buccal or lingual external root resorption, sagittal sections afford the best image characterization of the resorption process.

Influence of voxel size in the diagnostic ability of cone beam tomography to evaluate simulated external root resorption.

This study assessed in vitro the diagnostic ability of cone beam computed tomography (CBCT) scans with different voxel resolutions in the detection of simulated external root resorption (ERR). For that purpose, 59 teeth were viewed through iCAT tomography (Imaging Sciences International, Inc, Hatfield, PA) following three protocols in which the variation was the voxel resolution (0.4, 0.3, and 0.2mm). A calibrated examiner blinded to the protocol assessed the images through the i-CAT View software (Imaging Sciences International, Inc). The chi-square statistical analysis did not show associations between voxel resolution, section plane, size of cavity, and radicular third. Sensitivity and specificity values were similar. However, likelihood ratio values of 6.4 for a 0.4-mm voxel, 16 for a 0.3-mm voxel, and 12 for a 0.2-mm voxel were found. It was concluded that CBCT is a reliable method for the investigation of simulated ERR, and a 0.3-mm voxel appeared to be the best protocol, associating good diagnostic performance with lower X-ray exposure.

Reproducibility of cephalometric measurements made by three radiology clinics.

The purpose of this study was to assess reproducibility of cephalometric measurements in cephalograms obtained by three dentomaxillofacial radiology clinics. Forty lateral cephalometric radiographs were selected and sent at different times to three different clinics for cephalometric analyses. Each clinic digitized the radiographs with the same resolution, and landmarks were located with the mouse pointer directly on the digitized radiographic image on the screen. Three cephalograms were obtained from each radiograph, totaling 120 analyses. Data were analyzed with analysis of variance. Of the 32 factors studied, reproducibility of results was satisfactory for only four factors: position of maxilla relative to anterior cranial base, inclination of occlusal plane relative to anterior cranial base, position of lower incisor relative to nasion-pogonion line, and soft-tissue profile of face (P < .05). Differences in cephalometric measurements were present and such differences were significant for most factors analyzed. The different cephalometric measurements obtained by the three dental radiology clinics were not reproducible.

Dental findings in GAPO syndrome: case report.

This article reports the case of a young female adult with GAPO syndrome who presented as a peculiar dental finding unerupted primary and permanent dentitions, which resembled total anodontia on clinical examination. A cephalometric analysis was performed to investigate the alterations in facial bone development. This is the 9th GAPO syndrome case reported in a Brazilian patient.

Clinical variability in KBG syndrome: report of three unrelated families.

The KBG syndrome is characterized by short stature, macrodontia, a specific combination of minor anomalies, developmental delay, and/or mental retardation. We reported on four patients from three unrelated families. The most frequent clinical findings were: atypical face, long/flat philtrum, thin upper lip, macrodontia, dental malposition, enamel hypoplasia, and cleft teeth. Skeletal anomalies such as cervical ribs and vertebral abnormalities were also noted. Hand anomalies were observed in three patients. Mental retardation and developmental delay were present in three of the four patients. There is wide clinical variability in the expression of this syndrome. The males are usually more severely affected then the females, suggesting possible X-linked inheritance in some cases.