Influence of CBCT filters and contrast adjustments on peri-implant buccal bone thickness measurement and blooming expression.

OBJECTIVES: To assess whether filter and contrast adjustments can improve the accuracy of CBCT in measuring the buccal bone thickness (BBT) adjacent to dental implants by reducing blooming artifacts. MATERIALS AND METHODS: Homogeneous bone blocks with peri-implant BBT of 0.3 mm, 0.5 mm, and 1 mm were scanned using the Orthophos SL system. Three dentists measured the BBT in 234 CBCT scans under different settings of contrast adjustments and 'Sharpen' filter activation. Additionally, implant diameter measurements were taken to assess blooming artifact expression. The differences between tomographic and actual measurements of BBT and implant diameter [(CBCT - actual) * 100 / actual] were subjected to Mixed ANOVA (α = 0.05). RESULTS: The group with the thinnest BBT (0.3 mm) had the greatest difference between tomographic and actual measurements (79.9% ± 29.0%). Conversely, the 0.5 mm (36.1% ± 38.4%) and 1 mm (29.4% ± 12.3%) groups exhibited lower differences (p < 0.05). 'Sharpen' filter activation reduced blooming expression since it resulted in a lower difference for implant diameter (p < 0.05), but it did not influence BBT measurements (p = 0.673). Contrast settings had no impact on BBT (p = 0.054) or implant diameter measurements (p = 0.079). CONCLUSION: Although filter activation reduced blooming artifacts, neither filter nor contrast adjustments improved the accuracy of CBCT in measuring peri-implant BBT; actual BBT influenced this task. CLINICAL RELEVANCE: When assessing the peri-implant buccal bone plate in the CBCT system studied, dental surgeons may find it beneficial to adjust contrast and apply filters according to their preferences, since such adjustments were found to have no adverse effects on the diagnostic accuracy of this task. The use of the 'Sharpen' filter may lead to improved representation of implant dimensions.

Impact of enhancement filters of a CMOS system on halo artifact expression at the bone-to-implant interface.

OBJECTIVE: To assess the impact of enhancement filters on the formation of halo artifacts in radiographs of dental implants obtained with a complementary metal oxide semiconductor (CMOS) system. METHODS: Digital radiographs of dental implants placed in dry human mandibles were processed with the Noise Reduction smoothing filter, as well as the Sharpen 1, Sharpen 4, and Sharpen UM high-pass filters available in the CLINIVIEW™ software (Instrumentarium Dental, Tuusula, Finland). Subjective analysis involved evaluating the left, right, and apical surfaces of each implant for the presence of much, few, or no halo. The objective analysis involved measurement of the halo area using the Trainable Weka Segmentation plugin (ImageJ, National Institutes of Health, Bethesda, MD, USA). Data were analyzed using Friedman's test (subjective analysis) and ANOVA (objective analysis) (α = 5%). RESULTS: In the subjective evaluation, the Sharpen 4 filter produced more radiographs with much halo present, and in the objective evaluation, a bigger halo area when compared to the original images and the Noise Reduction filter for all surfaces (p < 0.05). CONCLUSIONS: When evaluating dental implants, priority should be given to original images and those enhanced with smoothing filters since they exhibit fewer halo artifacts. CLINICAL RELEVANCE: Post-processing tools, such as enhancement filters, may improve the image quality and assist some diagnostic tasks. However, little is known regarding the impact of enhancement filters in halo formation on CMOS systems, which have been increasingly used in dental offices.

High-density objects in exomass affect the volume of high-density objects inside the field of view.

OBJECTIVES: To evaluate the effect of the presence and the number of high-density objects in the exomass on the volume of a high-density object in cone-beam CT (CBCT). METHODS: Cylinders of cobalt-chromium (Co-Cr), titanium (Ti), and zirconium (Zi) were inserted into a polymethylmethacrylate phantom in five different combinations of number and position: 1-no cylinder; 2-one cylinder in a posterior region; 3-one cylinder in an anterior region; 4-two cylinders in posterior regions; and 5-three cylinders in anterior and posterior regions. The phantom underwent CBCT scanning using OP300 and X800 systems, with the afore mentioned cylinders of the same composition placed in the exomass and an additional high-density cylinder placed in the centre of the field of view (FOV), corresponding to the left-anterior region. The tomographic volume of the cylinder inside the FOV was measured using semi-automatic segmentation. The volumetric alteration (VA) between the segmented and physical volumes, in percentage, was compared among the experimental groups using repeated measures ANOVA and Tukey post-hoc (α = 5%). RESULTS: The factors material, combination, and their interaction affected the volume or both CBCT systems. In OP300, more cylinders in the exomass reduced the VA, mainly for Co-Cr. In X800, more cylinders in the exomass tended to increase the VA inside the FOV, except for Zi. CONCLUSIONS: In general, the presence of high-density objects in the exomass influences the VA of the object inside the FOV, although this oscillates according to object composition, number and position in the exomass, and CBCT system.

The effect of voxel and field of view size on the volumetric alteration artifact of high-density materials with 2 cone beam computed tomography devices.

OBJECTIVE: We investigated the influence of voxel and field of view (FOV) sizes on expression of the volumetric alteration artifact (VAA) of 5 high-density materials in 2 cone beam computed tomography (CBCT) devices. STUDY DESIGN: Cylinders of amalgam, cobalt-chromium, gutta-percha, titanium, and zirconium were individually positioned in a polymethyl methacrylate phantom. OP300 Maxio and ProMax 3D Classic CBCT devices were used to acquire images with varying voxel and FOV sizes, totaling 585 scans. Two evaluators segmented the high-density cylinder images to obtain the tomographic volumes. The difference between the tomographic and physical volume of each cylinder (i.e., volumetric alteration) was calculated. Statistical analysis was conducted with multiway ANOVA and the Tukey post hoc test (α = 5%). Evaluator reliability was measured with the intraclass correlation coefficient (ICC). RESULTS: All studied parameters and nearly all interactions influenced the VAA (P < .05). The post hoc test demonstrated less volumetric alteration for the smallest voxel sizes, 61 × 78 mm FOV, and gutta-percha for OP300, and for the smallest voxel sizes, 80 × 80 mm FOV, and gutta-percha and titanium for ProMax 3D (P < .05). The ICC demonstrated perfect reliability (1.00). CONCLUSIONS: Voxel and FOV sizes influenced VAA expression. Using smaller voxel sizes, the 61 × 78 mm FOV for OP300 and the 80 × 80 mm FOV for ProMax 3D, and materials with lower density and lower atomic number reduced VAA expression.

Influence of notebook computers screens and undergraduate level of dental students in the radiographic detection of carious lesions

Aim: To evaluate the influence of notebook computers screens and undergraduate level of dental students in the radiographic detection of carious lesions. Methods: Bitewing digital radiographs were presented to 3rd and 5th year dental students in three different notebooks computers: Notebook 1 with anti-glare screen (1366×768 pixels), Notebook 2 without anti-glare screen (1366×768 pixels), and Notebook 3 with anti-glare screen (1920×1080 pixels). A reference standard based on a consensus analysis was set by three senior professors of Oral Radiology and Cariology. Sensitivity, specificity and accuracy values were measured and submitted to two-way ANOVA at a significance level of 5%. Results: Notebook 2 provided significantly lower sensitivity values (Mean 56.5% ± 2.94) than notebook 3 (71.1% ± 2.82) (p = 0.002). We found no statistically significant differences between the two undergraduate years (p > 0.05). Conclusion: The anti-glare screen of notebook computers screens can influence the radiographic detection of carious lesions, but the undergraduate level of dental students does not influence this diagnostic task

A unique artificial intelligence-based tool for automated CBCT segmentation of mandibular incisive canal.

OBJECTIVES: To develop and validate a novel artificial intelligence (AI) tool for automated segmentation of mandibular incisive canal on cone beam computed tomography (CBCT) scans. METHODS: After ethical approval, a data set of 200 CBCT scans were selected and categorized into training (160), validation (20), and test (20) sets. CBCT scans were imported into Virtual Patient Creator and ground truth for training and validation were manually segmented by three oral radiologists in multiplanar reconstructions. Intra- and interobserver analysis for human segmentation variability was performed on 20% of the data set. Segmentations were imported into Mimics for standardization. Resulting files were imported to 3-Matic for analysis using surface- and voxel-based methods. Evaluation metrics involved time efficiency, analysis metrics including Dice Similarity Coefficient (DSC), Intersection over Union (IoU), Root mean square error (RMSE), precision, recall, accuracy, and consistency. These values were calculated considering AI-based segmentation and refined-AI segmentation compared to manual segmentation. RESULTS: Average time for AI-based segmentation, refined-AI segmentation and manual segmentation was 00:10, 08:09, and 47:18 (284-fold time reduction). AI-based segmentation showed mean values of DSC 0.873, IoU 0.775, RMSE 0.256 mm, precision 0.837 and recall 0.890 while refined-AI segmentation provided DSC 0.876, IoU 0.781, RMSE 0.267 mm, precision 0. 852 and recall 0.902 with the accuracy of 0.998 for both methods. The consistency was one for AI-based segmentation and 0.910 for manual segmentation. CONCLUSIONS: An innovative AI-tool for automated segmentation of mandibular incisive canal on CBCT scans was proofed to be accurate, time efficient, and highly consistent, serving pre-surgical planning.

Detection of misfits at the abutment-prosthesis interface in the esthetic zone: Implications of the radiographic technique and the magnitude of the misfit.

STATEMENT OF PROBLEM: Misfits in the abutment-prosthesis interface represent a setback for implant-supported prostheses. Periapical radiographs have been used as an auxiliary method in the evaluation of prosthesis fit to the abutments; however, the evidence supporting the use of this method is still restricted to studies of low to moderate quality. Furthermore, studies on the diagnostic accuracy of different periapical techniques used to detect misfits in the abutment-prosthesis interface, especially in the esthetic zone, are lacking. PURPOSE: The purpose of this in vitro study was to assess the discrimination power of 3 periapical radiographic techniques in detecting misfits at the abutment-prosthesis interface in the esthetic zone and evaluate whether the magnitude of the misfit influenced the diagnosis. MATERIAL AND METHODS: A total of 15 implants with an internal conical connection were installed in the central incisor region in polyamide jaws. Custom ceramic copings for cemented crowns were made by using a computer-aided design and computer-aided manufacturing (CAD-CAM) system. Misfits of 50, 100, and 150 µm were simulated by interposing 1, 2, or 3 50-µm-thick polyester strips at the abutment-prosthesis interface; the absence of the strip represented the control group. Digital radiographs were obtained by using film holders for the following periapical techniques: bisecting angle (PBA), standard paralleling (PSP), and modified paralleling (PMP). Two radiologists and 1 prosthodontist evaluated a total of 180 radiographs. The values of the area under the receiver operating characteristic curve (Az) were regarded as a measure of diagnostic accuracy and subjected to the Friedman test with post hoc Durbin-Conover (α=.05). RESULTS: The PSP (Az=0.873) had higher Az values than the PBA (Az=0.753) for the 50-µm misfits (P<.05). Larger misfits resulted in greater accuracy than smaller misfits (P<.05). Interactions between the factors radiographic technique and misfit magnitude resulted in statistically significant differences for all comparisons (P<.05), except between the PSP for the 100-µm misfits (Az=0.976) and the PMP for the 150-µm misfits (Az=0.998). CONCLUSIONS: The PSP was more accurate than the PBA in detecting the 50-µm misfits at the abutment-prosthesis interface; larger misfits resulted in more accurate diagnoses, regardless of the technique used.

Does enhancement filter application increase the diagnostic accuracy of misfit detection at the implant-prosthesis interface?

STATEMENT OF PROBLEM: Misfits at the implant-prosthesis interface may increase complications in dental implants and affect peri-implant tissue health. Periapical radiographs are the most used imaging examinations for detecting misfits at the implant-prosthesis interface, although digital systems have largely replaced film-based radiographs. Whether postprocessing tools such as enhancement filters assist diagnosis by highlighting misfits is unclear. PURPOSE: The purpose of this in vitro study was to assess the influence of enhancement filter application in the diagnostic accuracy of misfit detection at the implant-prosthesis interface. MATERIAL AND METHODS: A total of 32 dental implants were placed in dry human mandibles. A polyester strip was inserted at the implant-prosthesis interface to simulate a 50-µm misfit; prosthetic crowns installed directly on the implant platforms were used as controls. Standard paralleling periapical images were acquired by using a semidirect system (photostimulable phosphor plate) with the application of Highlight, Invert, and Colorization filters, as well as a direct system (metal oxide complementary semiconductor sensor) with filters Sharpness 3, Invert, and Pseudocolorization. Oral radiologists evaluated the images with and without the application of filters. The areas under the receiver operating characteristics curves (Az values), sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were calculated. The Az values were compared with the receiver operating characteristic (ROC) curves comparison test of the Epidat 3.1 software (α=.05). RESULTS: Although images without filter application presented descriptively higher diagnostic values than those with filter application, the Az values for images with and without filter application in both semidirect and direct systems showed no significant differences (P>.05). CONCLUSIONS: Enhancement filter application did not significantly influence the diagnostic accuracy of misfit detection at the implant-prosthesis interface.

Comparison of the expression of the volumetric alteration artifact in cylindrical and triangular fields of view in two cone-beam computed tomography devices.

OBJECTIVE: To compare the expression of the volumetric alteration (VA) artifact between cylindrical and convex triangular fields of view (FOVs) using high-density materials in different positions in two cone-beam computed tomography (CBCT) devices. MATERIALS AND METHODS: Cylinders of five high-density materials (amalgam, chromium-cobalt, gutta-percha, titanium, and zirconium) with known physical volume were individually submitted to CBCT acquisition in four positions inside a polymethylmethacrylate phantom using two different FOV shapes (convex triangular and cylindrical) on the Veraviewepocs® R100 (R100) and Veraview® X800 (X800) devices. Two oral radiologists obtained the tomographic volumes by segmenting each cylinder. The difference between the tomographic and physical volumes corresponded to the VA. These values were analyzed by intraclass correlation coefficient and analysis of variance for repeated measures with Tukey post hoc test (α = 5%). RESULTS: The FOV influenced the VA only in the X800 device (p = 0.014): the VA in the triangular FOV was greater than in the cylindrical FOV. The VA in the triangular FOV of the X800 device was greater than the R100 device (p < 0.0001). The material influenced the expression of the VA only in the R100 device (p < 0.0001); gutta-percha presented the highest VA, being underestimated, and differing from the other materials (p < 0.01). CONCLUSION: The triangular FOV increased the VA of high-density materials in the X800 device. CLINICAL RELEVANCE: It is important to know if there is an influence on the volumetric alteration artifact of dental materials due to the different image formation geometry in the convex triangular FOV.

Influence of radiographic acquisition methods and visualization software programs on the detection of misfits at the implant-abutment interface: An ex vivo study.

STATEMENT OF PROBLEM: Misfits at the implant-prosthesis interface may compromise implant-supported prostheses. Periapical radiographs are frequently used to detect misfit and can be obtained by using digital or film-based systems; however, which radiographic acquisition method and visualization software program provides the greatest accuracy is unclear. PURPOSE: The purpose of this ex vivo study was to evaluate the influence of 3 radiographic acquisition methods (complementary metal oxide semiconductor [CMOS] sensor, phosphor plates, and radiographic films) and 2 visualization software programs (proprietary and third-party) on the detection of misfits at the implant-prosthesis interface. MATERIAL AND METHODS: Thirty-two dental implants were placed in dry human mandibles. Misfits were simulated by inserting a 50-µm polyester strip at the implant-prosthesis interface; prosthetic crowns installed directly over the implant platforms were considered as controls. Standard parallel periapical radiographs were obtained by using a CMOS sensor, a phosphor plate, and radiographic films. Five dentists assessed the digital radiographs for the presence or absence of misfits at the implant-prosthesis interface by using the proprietary software program and a third-party software program; film-based radiographs were evaluated on a light box. The area under the receiver operating characteristic curves (Az values) were compared (α=.05); sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were also estimated. RESULTS: All diagnostic and Az values were higher for the phosphor plate than for the CMOS sensor and the film-based methods (P<.05), regardless of the viewing software program used (proprietary or third-party) (P>.05). CONCLUSIONS: The use of phosphor plates positively influenced the diagnostic accuracy for the detection of misfits at the implant-prosthesis interface, irrespective of the viewing software program used.

Influence of Voxel Size and Filter Application in Detecting Second Mesiobuccal Canals in Cone-beam Computed Tomographic Images.

INTRODUCTION: This study assessed the influence of voxel size and filter application in detecting second mesiobuccal (MB2) canals in cone-beam computed tomographic (CBCT) images. METHODS: Using the OP300 CBCT system (Instrumentarium, Tuusula, Finland) and 3 voxel size protocols (80 µm, 125 µm, and 200 µm), we scanned 40 first molars: 20 with an MB2 canal and 20 without. All molars received silver palladium pins on the palatal root, whereas the non-MB2 molars were also filled with gutta-percha. Five oral radiologists assessed the presence of an MB2 canal under 3 filter application conditions: without filter, with sharpen 1 × filter, and with sharpen 2 × filter. Intra- and interobserver reproducibility was evaluated using the weighted kappa index. We compared the area under the receiver operating characteristic curves with SPSS Statistics v.20.0 (IBM Corp, Armonk, NY) using 2-way analysis of variance and the Tukey post hoc test with 5% significance level. RESULTS: Our analysis found median intra- and interobserver agreement values of 0.70 and 0.56, respectively. The 80-µm voxel with sharpen 1 × filter image group had the highest sensitivity, accuracy, and negative predictive values. As for specificity and positive predictive, the 80-µm voxel group without filter application presented the highest values. The areas under the receiver operating characteristic curve were higher in the 80-µm groups than in the 125-µm and 200-µm voxel size groups (P < .05). We found no differences among the filters used (P = .22) or for the filter-voxel size interactions (P = .88). CONCLUSIONS: A smaller voxel size increased the accuracy in detecting MB2 canals, whereas the enhancement filters did not.

Distortion or magnification? An in vitro cone-beam CT study of dimensional changes of objects with different compositions.

OBJECTIVES: To assess whether dimensional changes occur as shape distortion (unevenly), contraction or magnification (evenly) in cone beam computed tomography (CBCT) considering materials, anatomical regions and metal artefact reduction algorithms. METHODS: Four cylinders of amalgam (Am), cobalt-chromium (Co-Cr), gutta-percha (Gu), titanium (Ti) and zirconium (Zi) were inserted inside a polymethylmethacrylate phantom in anterior and posterior regions for acquisitions in Picasso Trio and OP300 with MAR enabled and disabled. Two observers measured the dimensions of each cylinder in three axes: Y (height), Z (antero posterior diameter) and X (latero-lateral diameter). Repeated measures ANOVA with Tukey post-hoc test compared the data (α = 5%). RESULTS: Shape distortion occurred for all materials in anterior region of Picasso Trio without MAR (p < 0.05). With MAR enabled, Gu and Ti contracted (p ≥ 0.05), while the others showed distortion (p < 0.05). In posterior region, all materials distorted in both MAR conditions (p < 0.05), except Gu, which magnified without MAR (p ≥ 0.05) and contracted unevenly with MAR (p < 0.05). In anterior region of OP300, all materials magnified without MAR, (p ≥ 0.05) and had shape distortion with MAR (p < 0.05). In posterior region, only Am showed magnification without MAR (p ≥ 0.05), while all materials presented shape distortion with MAR (p < 0.05). CONCLUSION: Dimensional changes of high-density materials in CBCT can be either a magnification, a contraction or a distortion; the last condition is the most prevalent. Furthermore, changes differ considering material, anatomical region and MAR condition.

Misfit detection in implant-supported prostheses of different compositions by periapical radiography and cone beam computed tomography: An in vitro study.

STATEMENT OF PROBLEM: Misfits at the implant-abutment joint (IAJ) can cause the biological and mechanical failure of implant therapy. Standard parallel periapical radiography (PERI) is the method of choice for assessing the fitting of implant-supported prostheses. Although current guidelines do not support the use of cone beam computed tomography (CBCT) solely for misfit detection, CBCT scans can also register misfits as imaging findings. Whether the material used for prostheses manufacturing influences misfit appearance in PERI and CBCT images is unknown. PURPOSE: The purpose of this in vitro study was to assess the influence of the type of prosthesis material on misfit detection at the IAJ by using PERI and CBCT. MATERIAL AND METHODS: Thirty-two implants with an external hexagon connection were placed in dried human mandibles. Implant-supported crowns were manufactured with different materials and allocated to 3 experimental groups: metal-ceramic (MC), titanium abutment veneered with acrylic resin (TIT), and zirconia abutment veneered with glass-ceramic (ZIR). All crowns were installed both with and without a simulated 200-µm-thick gap at the IAJ (n=64) and were assessed by PERI and CBCT scans. Four dentists evaluated the images for the presence or absence of misfit. Statistical analysis included the Kappa test and areas under the receiver operating characteristics curve (Az values) comparisons (α=.05). RESULTS: Kappa values indicated almost perfect intraevaluator and interevaluator reproducibility for PERI and ranged from fair to almost perfect for CBCT. For PERI, Az values were not significantly different among the MC (0.995), TIT (0.997), and ZIR groups (1.000) (P>.05). Regarding CBCT, the Az values found for TIT (0.941) and MC (0.890) were significantly higher than for ZIR (0.762) (P<.05). Az values for PERI were significantly higher than for CBCT (P<.05). CONCLUSIONS: The type of prosthesis material did not influence misfit detection at the IAJ with PERI; however, ZIR had lower diagnostic accuracy than TIT and MC implant-supported crowns with CBCT.

Evaluation of different teaching methods in the radiographic diagnosis of proximal carious lesions.

OBJECTIVES: To evaluate four different teaching methodologies in the radiographic diagnosis of proximal carious lesions and in the students' perception of these methodologies. METHODS: 71 undergraduate dental students were subdivided into 4 groups according to the teaching methodologies used (traditional, hybrid, e-learning and problem-based learning). All methods were applied by two properly trained researchers. Initially, students completed a pre-methodology test (index test). After applying the teaching methodologies, the students were submitted to a post-methodology test containing periapical radiographs for evaluation of proximal carious lesions. Then, the students answered a questionnaire to verify their perception of the different teaching methodologies. Statistical analysis was done. RESULTS: There were no relationship between the results of pre- and post-methodologies tests, irrespective of the teaching methodology employed (p > 0.05). No differences between the teaching methodologies studied (p > 0.05) were found regarding the amount of correct answers. However, the students who participated in the active (e-learning and problem-based learning) and hybrid teaching methodology reported a positive impact in relation to their diagnostic skills at the questionnaire. CONCLUSIONS: All the tested methodologies had a similar performance; however, the traditional methodology showed less acceptance by the students when analyzed subjectively and comparatively. The results of the present study increase comprehension about teaching methodologies for radiographic diagnosis of proximal carious lesions, and there is a potential to build on the knowledge base and provide practical support for students and educators.

Influence of windowing and metal artefact reduction algorithms on the volumetric dimensions of five different high-density materials: a cone-beam CT study.

OBJECTIVE: To assess the influence of windowing and metal artefact reduction (MAR) algorithms on the volumetric dimensions of high-density materials using two CBCT systems. METHODS: Four cylinders of amalgam, cobalt-chromium, gutta-percha, titanium and zirconium, were manufactured and their physical volumes (PV) were measured. A polymethyl methacrylate phantom containing the cylinders was submitted to CBCT acquisitions with Picasso Trio and OP300 units with their MAR enabled and disabled. The tomographic volume (TV) of all the cylinders was obtained by semi-automatic segmentation using two windowing adjustments: W1-large window width and upper window level; W2-narrow window width and low window level. Volumetric distortion was expressed as the difference between TV and PV. Statistics comprised intraclass correlation coefficient (ICC) and analysis of variance (ANOVA) for repeated measures with Tukey post hoc test (α = 5%). RESULTS: The ICC values ​​indicated excellent reproducibility of TV. Gutta-percha and titanium resulted in the smallest volumetric distortion. Using W1 provided less volumetric distortion for almost all experimental conditions (p < 0.05). Activating MAR algorithm of Picasso Trio underestimated gutta-percha and titanium TV (p < 0.05) and was inefficient in significantly reducing the volumetric distortion of the other materials (p > 0.05). Disabling MAR algorithm of OP300 resulted in smaller volumetric distortion for almost all experimental conditions (p < 0.05). CONCLUSIONS: The TV of gutta-percha and titanium were closer to the PV. In general, the MAR algorithms of both systems were inefficient in significantly reducing the volumetric distortion of high-density materials. We encourage the use of large window width and upper window level to evaluate high-density materials.

Thoracic pain associated with an odontogenic infection: An unusual Lemierre's syndrome.

Lemierre's syndrome is characterized by thrombophlebitis in the internal jugular vein after an infection in the area of the head or neck, mostly in the form of pharyngitis and/or tonsillitis. It may also result from less common conditions, such as odontogenic infections, but this condition has not often been reported in the dental literature. The syndrome's main etiological agent is Fusobacterium necrophorum, and it most commonly occurs in young adults. This study reports the clinical case of a 34-year-old female patient of poor socioeconomic status with a history of pericoronitis, who reported having a chest pain that radiated to the upper limbs, along with dyspnea. The computed tomography of her neck provided evidence of an acute thrombus in the right internal jugular vein. The treatment comprised antibiotic and anticoagulant therapy in addition to the extraction of her third molar and some residual roots. This report highlights the perils of systemic complications through dental infection, including the risk of death.

More frequent detection of calcified carotid atherosclerotic plaques and mineralized laryngeal cartilages on digital than on film-based panoramic radiographs.

PURPOSE: To determine whether calcified carotid atherosclerotic plaques (CCAPs) and mineralized laryngeal cartilages (MLCs) were more frequently detected on digital or film-based panoramic radiographs. The clinical relevance of this question is that some radiopacities seen on digital radiographs may correspond to medium-density tissues that are not necessarily mineralized. MATERIALS AND METHODS: Data were collected from panoramic radiographs and the respective reports issued by 2 private oral radiology centers. A total of 388 radiographs and reports were divided into film-based (group A) and digital (group D) radiographs. The frequencies of CCAPs and MLCs were analyzed using the Fisher exact test, and odds ratios were also calculated (α=1%). RESULTS: The mean age of patients whose reports and radiographs showed CCAPs and/or MLCs ranged from 50.1 to 54.1 years. There was a predominance of females. A higher frequency of CCAPs and MLCs was observed in group D than in group A at both centers (P<0.01). CCAPs and MLCs were detected 4 times more frequently in group D than in group A at one of the centers. CONCLUSION: CCAPs and MLCs were more frequently detected on digital than on film-based panoramic radiographs. Further studies are needed to determine whether such radiopacities do indeed correspond to mineralized, rather than medium-density, tissues.

Enamel-Renal-Syndrome: case report.

AIMS: to describe a case in which dental changes were observed and investigation proceeded to consider Enamel-Renal-Syndrome (ERS), a rare disorder that associates amelogenesis imperfecta with nephrocalcinosis. CASE REPORT: an 11-year-old male patient upon intraoral examination revealed generalized gingival hyperplasia, a few teeth were absent clinically and the remaining ones were yellowish-brown in color. The enamel alterations were suggesting of amelogenesis imperfecta. Unerupted teeth with increased pericoronal spaces, suggesting hyperplasic follicles or dentigerous cysts and an enamel with lower thickness and density were observed in the panoramic radiography. The patient was referred for an assay to investigate mucopolysaccharidosis; however, it was negative. A renal ultrasound showed bilateral nephrocalcinosis and laboratory exams, including calcium, phosphate, and creatinine levels were below the average. An incisional gingival biopsy showed numerous round to ovoid basophilic calcifications in the connective tissue. The final diagnosis was ERS. CONCLUSION: Dentists should refer patients with similar clinical presentation for renal ultrasound evaluation in order to rule out the possible diagnosis of ERS.

Diagnostic accuracy of 4 intraoral radiographic techniques for misfit detection at the implant abutment joint.

STATEMENT OF PROBLEM: A misfit or gap at the implant-abutment joint (IAJ) requires detection as it may compromise the health of the peri-implant tissue. However, which radiographic technique provides the most orthogonal relationship between the central beam and the implant/image receptor is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the diagnostic accuracy of 4 intraoral radiographic techniques on misfit detection at the IAJ. MATERIAL AND METHODS: Twenty implants were placed in polyamide jaws, and customized dental implant abutments with a metal collar were installed. Different gaps were simulated by placing one or three 50-µm-thick polyester strips at the IAJ; the absence of the strip represented the control group (no gap). The 4 radiographic techniques were evaluated by using different film holders: a periapical with bisecting angle (PBA), a bitewing interproximal (BI), a periapical with standard paralleling (PSP), and a periapical with modified paralleling (PMP) holder (with a custom-made paralleling index). A total of 240 digital radiographs were evaluated by 4 clinicians experienced with dental implants. Differences were evaluated by using receiver operating characteristic (ROC) curves (Az) and Fisher tests (α=.05). Diagnostic values (sensitivity, specificity, accuracy, and positive and negative predictive values) were also obtained. The Kappa test was used to assess intra- and interevaluator reproducibility, which ranged from moderate to almost perfect. RESULTS: All diagnostic values, except specificity, were lower for the PBA technique for both the 50- and 150-µm gaps. Az values for the PBA technique were significantly lower than those obtained for the other 3 techniques (P<.05), which did not differ from each other. The 150-µm gaps were more easily detected than the 50-µm gaps only for PBA (P<.05). CONCLUSIONS: The BI, PSP, and PMP techniques detected misfits at the IAJ most accurately. The PBA technique is not recommended for this purpose.